Hitachi ZX 690LCH-7 690LCR-7 Hydraulic Excavator Operational Technical Manual PNTTJBQ40 PDF (1) by www.heydownloads.com

PART NO. ZX690LCH-7 • 690LCR-7 HYDRAULIC EXCAVATOR TECHNICAL MANUAL OPERATIONAL PRINCIPL TOJBQ40-EN-00

PRINTED IN JAPAN (E) 2020, 02

TOJBQ40-EN-00

Technical Manual Operational Principle

690LCH-7 690LCR-7

Hydraulic Excavator

Service Manual consists of the following separate Part No. Technical Manual (Operational Principle) : Vol. No.TOJBQ40-EN Technical Manual (Troubleshooting) : Vol. No.TTJBQ40-EN Workshop Manual : Vol. No.WJBQ40-EN Engine Manual : Vol. No.ETJAQ51-EN, EWJAQ51-EN

INTRODUCTION To The Reader This manual is written for an experienced technician to provide technical information needed to maintain and repair this machine. The machine specification and description according to destination may be explained on this manual. ● Be sure to thoroughly read this manual for correct product information and service procedures. ● If you have any questions or comments, at if you found any errors regarding the contents of this manual, please contact using “Service Manual Revision Request Form” at the end of this manual. (Note: Do not tear off the form. Copy this form for usage.) •

Service Material Development Center Hitach Construction Machinery Co., Ltd.

•

TEL: 81-29-832-9673

•

FAX: 81-29-831-1162

• E-mail: HCM-TIC-GES@hitachi-kenki.com All information, illustrations and specifications in this manual are based on the latest product information available at the time of publication. The right is reserved to make changes at any time without notice.

Additional References Please refer to the other materials (operator’s manual, parts catalog, engine technical material and Hitachi training material etc.) in addition to this manual.

Manual Composition This manual consists the Technical Manual, the Workshop Manual and the Engine Manual. ● Information included in the Technical Manual: Technical information needed for redelivery and delivery •

Operation and activation of all devices and systems, operational performance tests, and troubleshooting procedures.

● Information included in the Workshop Manual: Technical information needed for maintenance and repair of the machine •

Tools and devices needed for maintenance and repair, maintenance standards, and removal / installation and assemble / disassemble procedures

● Information included in the Engine Manual: Technical information needed for redelivery and delivery and maintenance and repair of the machine •

Operation and activation of all devices and systems, troubleshooting and assemble / disassemble procedures

Page Number Each page has a number, located on the center lower part of the page. Each number contains the following information: ● Technical Manual: T 1-3-5 T

Technical Manual

Section Number

Group Number

Consecutive Page Number for Each Group

● Workshop Manual: W 1-3-2-5 W

Workshop Manual

Section Number

Group Number

TOJBQ40-EN-00(07/02/2020)

IN-1

INTRODUCTION 2

Sub Group Number

Consecutive Page Number for Each Group

Trademark AdBlue® is a registered trademark of the Verband der Automobilindustrie e.V. (VDA).

Safety Alert Symbol and Headline Notations In this manual, the following safety alert symbol and signal words are used to alert the reader to the potential for personal injury of machine damage.

WARNING This is the safety alert symbol. When you see this symbol, be alert to the potential for personal injury. Never fail to follow the safety instructions prescribed along with the safety alert symbol. The safety alert symbol is also used to draw attention to component/part weights. To avoid injury and damage, be sure to use appropriate lifting techniques and equipment when lifting heavy parts.

CAUTION Indicates potentially hazardous situation which could, if not avoided, result in personal injury or death. This is also provided before the indication of mass to draw attention to safety during handling of the machine.

IMPORTANT Indicates a situation which, if not conformed to the instructions, could result in damage to the machine. This header is given to matters that are important in terms of operation and management.

NOTE Indicates supplementary technical information or know-how.

Units Used SI Units (International System of Units) are used in this manual. A table for conversion from SI units to other system units is shown below for reference purposes. Quantity Length

To Convert From

Into

Multiply By

0.03937

0.003281

US gal

0.2642

US qt

1.057

yd3

1.308

Weight

2.205

Force

kgf

0.10197

lbf

0.2248

Torque

N·m

kgf·m

0.10197

Pressure

MPa

kgf/cm2

10.197

MPa

psi

145.0

Volume

TOJBQ40-EN-00(07/02/2020)

IN-2

INTRODUCTION Quantity Power

To Convert From

Into

Multiply By

1.360

1.341

Temperature

°C

°F

°C×1.8+32

Velocity

km/h

mph

0.6214

min-1

rpm

1.0

L/min

US gpm

0.2642

mL/rev

cc/rev

1.0

Flow rate

TOJBQ40-EN-00(07/02/2020)

IN-3

INTRODUCTION MEMO

TOJBQ40-EN-00(07/02/2020)

IN-4

SYMBOL AND ABBREVIATION Symbol and Abbreviation Symbol/Abbreviation

Name

Meaning

Technical manual (Operational Technical manual (Operational principle). principle)

Technical manual (Trouble shooting)

Technical manual (Troubleshooting).

T/M

Technical manual

Technical manual.

W, W/M

Workshop manual

Workshop Manual (Mounting/dismounting, disassembly and assembly of devices).

Main Controller

Main Controller. MC controls the engine, pumps, and valves ac cording to the machine operation condition.

ECM

Engine Control Module

Engine Controller. ECM controls the fuel injection amount and others according to the machine operation condition.

VGS

Variable Geometry System con Variable Turbocharger Controller. VGS is a system for efficiently troller supercharging even when the engine speed is low and the ex haust energy is low. Through adjustment of the nozzle open ing of the turbine housing, the turbine rotation speed is opti mized, the low-speed torque and acceleration are improved, and the power consumption and PM are reduced.

GSM

Global System for Mobile com Communication Controller. GSM is one of wireless communica munications controller tion methods and is used in over 100 countries centering around Europe and Asia and serves as the de facto global standard for mobile phones.

GPS

Global Positioning System

Global Positioning System.

CAN

Controller Area Network

CAN communication. CAN is ISO Standards of the serial com munication protocol (rules).

A/C

Air Conditioner

Air conditioner.

OP, OPT

Option

Optional item.

MPDr.

Maintenance Pro Dr.

MPDr. is software for conducting troubleshooting, monitoring, and adjustment.

A/I

Auto-Idle

Auto-Idle.

Warming-Up

Warming up.

Low (Slow) Idle

Slow Idle Engine Speed

ATT

Attachment

Attachment. In this document, it refers to an optional part such as breaker, pulverizer, and crusher.

HI, Hi

High

Travel fast speed position.

LO, Lo

Low

Travel slow speed position.

DPF

Diesel Particulate Filter

DPF (Diesel Particulate Filter) is a filter to remove fine particles including harmful substances in the exhaust gas of the diesel engine. Exhaust fine particle removing device.

DPD

Diesel Particulate Diffuser

DPD (Diesel Particulate Diffuser) is an exhaust gas purifying device (one type of DPF) that removes PM (particulate matter) in the exhaust gas of the diesel engine. DPD collects and filters PM in the exhaust gas using a ceramic filter and, when the PM accumulation amount has become large, incinerates the accu mulated PM at once and regenerates the filter.

DOC

Diesel Oxidation Catalyst

Oxidation catalyst for diesel. DOC oxidizes the unburnt fuel and raises the exhaust temperature.

TOJBQ40-EN-00(07/02/2020)

SY-1

SYMBOL AND ABBREVIATION Symbol/Abbreviation

Name

Meaning

CSF

Catalyzed Soot Filter

Filter. The filter collects PM, and removes it by burning it by means of high-temperature exhaust gas whose temperature has been raised by oxidation catalyst. The catalyst is also ap plied on the filter, thus accelerating burning of PM.

Particulate Matter

Particulate matter.

EGR

Exhaust Gas Recirculation

The EGR re-circulates a part of exhaust gas into intake mani fold and mixes it with intake-air to lower the burn temperature and suppress the generation of NOx (nitrogen oxide).

Moment Limiter

ML crane.

HRV

Hose Rupture Valve

Hose rupture valve.

LLC

Long Life Coolant

Coolant.

SCR

Selective Catalytic Reduction

The urea SCR system injects DEF to NOx in the exhaust of en gine to remove NOx.

DCU

Dosing Control Unit

Urea SCR System Controller. DCU controls the DEF injection amount and others according to the machine operation condi tion.

S/M

Supply Module

DEF supply module. The DEF supply module supplies the pres surized DEF to dosing module (D/M). When the key switch is set to the OFF position, it sucks DEF from DEF circuit to return it.

D/M

Dosing Module

Dosing Module. The dosing module (D/M) injects DEF into the exhaust piping according to the signal from DCU.

NOx

Nitrogen Oxide

Nitrogen oxide.

DEF

Diesel Exhaust Fluid

Urea water. This is urea water with a concentration of 32.5% that is specified in ISO 22241.

PLCU

Performance Level Control Unit PLCU is a controller to control AFL.

PBLI

Push Button Low Idle

Push button low idle. PBLI is described as audio mute/onetouch idle switch in this manual.

AFL

Auxiliary Function Lever

AUX function lever.

TOJBQ40-EN-00(07/02/2020)

SY-2

CONTRASTING LIST OF PART NAME Contrasting List of Part Name between Technical Manual and Parts Catalog Part name in technical manual

Part name in parts catalog

Part No.

Fuel Sensor (float)

FLOAT

YA00015407

Hydraulic Oil Temperature Sensor

SENSOR

4697482

MAF/Intake-Air Temperature Sensor

SENSOR

4664861

Ambient Temperature Sensor

SENSOR

4405815

Coolant Temperature Sensor

SENSOR;THERMO

YA00010305

Common Rail Pressure Sensor

RAIL ASM; COMMON

8982997730

Fuel Temperature Sensor

SENSOR;FUEL TEMP

8972249930

Crank Speed Sensor

SENSOR

YA00010304

Engine Oil Pressure Sensor

SENSOR;PRES

4657942

EGR Cooler Outlet Temperature Sensor 1

SENSOR;THERMO

YA00001667

EGR Cooler Outlet Temperature Sensor 2

SENSOR;THERMO

YA00001667

Intake Manifold Temperature Sensor

SENSOR;THERMO

YA00011515

Boost Pressure/Temperature Sensor

SENSOR;PRES

YA00001668

EGR Cooler Inlet Temperature Sensor 1

SENSOR;THERMO

YA00001666

EGR Cooler Inlet Temperature Sensor 2

SENSOR;THERMO

YA00001666

Differential Pressure Sensor

SENSOR;PRESSURE

YA00054794

Upstream NOx Sensor

SENSOR;NOX

YA00001705

Downstream NOx Sensor

SENSOR;NOX

YA00001705

DOC Outlet Exhaust Temperature Sensor

SENSOR;THERMO

YA00009436

DOC Inlet Exhaust Temperature Sensor

SENSOR;THERMO

YA00009436

SCR Exhaust Temperature Sensor

SENSOR;THERMO

YA00001706

Pump 1 Delivery Pressure Sensor

SENSOR;PRESSURE

4668254

Pump 2 Delivery Pressure Sensor

SENSOR;PRESSURE

4668254

Pump 1 Displacement Control Pressure Sensor

SENSOR;PRES.

4436536

Pump 2 Displacement Control Pressure Sensor

SENSOR;PRES.

4436536

Arm Roll-In Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Arm Roll-Out Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Bucket Roll-In Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Bucket Roll-Out Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Boom Raise Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Boom Lower Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Attachment Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Swing Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Travel Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

Front Pilot Pressure Sensor

SENSOR;PRESSURE

4436535

4-Spool Pilot Pressure Sensor

SENSOR;PRESSURE

4436536

5-Spool Pilot Pressure Sensor

SENSOR;PRESSURE

4436536

DEF Quality Sensor

UNIT;UREA

YA00055710

DEF Tank Level Sensor

UNIT;UREA

YA00055710

DEF Tank Temperature Sensor

UNIT;UREA

YA00055710

TOJBQ40-EN-00(07/02/2020)

CO-1

CONTRASTING LIST OF PART NAME Part name in technical manual

Part name in parts catalog

Part No.

Engine Oil Monitoring Sensor

SENSOR;OIL

YA00046690

Hydraulic Oil Monitoring Sensor

SENSOR;OIL

YA00052887

TOJBQ40-EN-00(07/02/2020)

CO-2

SECTION AND GROUP CONTENTS

SECTION1 GENERAL Group1

Specifications

Group2

Component Layout

Group3

Component Specifications

SECTION2 SYSTEM TECHNICAL MANUAL ( O p e r a t i o n a l P r i n c i p l e )

Group1

Controller

Group2

Control System

Group3

Engine System

Group4

Hydraulic System

Group5

Electrical System

SECTION3 COMPONENT OPERATION Group1

Pump Device

Group2

Swing Device

Group3

Control Valve

Group4

Pilot Valve

Group5

Travel Device

Group6

Signal Control Valve

Group7

Others (Upperstructure)

Group8

Others (Undercarriage)

MEMO

TOJBQ40-EN-00(07/02/2020)

GENERAL Specifications............................................T1-1-1 Specifications ZX690LCH-7, 690LCR-7 ......................... T1-1-1 Working Ranges ZX690LCH-7, 690LCR-7 .................... T1-1-2

Component Layout...................................T1-2-1 Main Component (Upperstructure) .............................. T1-2-1 Main Component (Undercarriage) ................................ T1-2-3 Main Component (Front Attachment) ......................... T1-2-4 Electrical System (Overview) ........................................... T1-2-5 Electrical System (Rear Tray) ............................................ T1-2-6 Electrical System (Switches)............................................. T1-2-7 Electrical System (Utility Space) ..................................... T1-2-8 Electrical System (Around Battery)................................ T1-2-9 Engine Oil Monitoring Sensor and Engine Oil Filter .................................................................................... T1-2-9 Hydraulic Oil Monitoring Sensor..................................T1-2-10 Engine ....................................................................................T1-2-11 Aftertreatment Device .....................................................T1-2-12 Pump Device .......................................................................T1-2-13 Control Valve .......................................................................T1-2-14 Signal Control Valve..........................................................T1-2-14 Pilot Check Valve................................................................T1-2-15 Swing Device.......................................................................T1-2-16 Travel Device .......................................................................T1-2-16 4-Spool Solenoid Valve Unit (Control Valve Side) ... .............................................................................................T1-2-17 4-Spool Solenoid Valve Unit (Hydraulic Oil Tank Side)...................................................................................T1-2-17 Expansion Tank...................................................................T1-2-18 Air Cleaner............................................................................T1-2-18 DEF Tank................................................................................T1-2-19 DEF Supply Module...........................................................T1-2-19 Coolant Control Valve.......................................................T1-2-20 Electric Fuel Pump and Fuel Filter................................T1-2-20 Radiator Fan Valve and Radiator Fan Motor.............T1-2-21 Oil Cooler Fan Valve and Oil Cooler Fan Motor .......T1-2-22 Shockless Valve...................................................................T1-2-22 Radiator Fan Valve .............................................................T1-2-23 Oil Cooler Fan Valve ..........................................................T1-2-23 Boom Upper Area ..............................................................T1-2-24 Arm Upper Area..................................................................T1-2-24 Distribution Valve (Upperstructure)............................T1-2-25 Auto-Lubrication Device .................................................T1-2-25

Component Specifications.......................T1-3-1 TOJBQ40-EN-00(07/02/2020)

Specifications of Engine .................................................... T1-3-1 Specifications of Engine Accessories............................ T1-3-2 Specifications of Hydraulic Component...................... T1-3-3 Specifications of Electrical Component....................... T1-3-4

MEMO

TOJBQ40-EN-00(07/02/2020)

SYSTEM Controller ..................................................T2-1-1 Outline of Controller........................................................... T2-1-1 CAN Circuit ............................................................................. T2-1-1

Control System..........................................T2-2-1 Outline of Control System ................................................ T2-2-1 Engine Control ...................................................................... T2-2-1 Engine Control System Layout........................................ T2-2-2 Engine Protection Control ................................................ T2-2-3 Engine Control Dial Control ............................................. T2-2-5 ECO Control............................................................................ T2-2-7 Power Mode (ECO/PWR/HP Mode) Switch Control ............................................................................................... T2-2-9 ECO/PWR Mode Travel Speed Increase Control......T2-2-11 Auto-Idle Control ...............................................................T2-2-13 Radiator Coolant Temperature Auto-Warming Up Control..............................................................................T2-2-15 Engine Speed Slow Down Control ..............................T2-2-17 One-Touch Idle Control (Option)..................................T2-2-19 Pump Control ......................................................................T2-2-21 Pump Control System Layout........................................T2-2-22 Pump Flow Rate Control .................................................T2-2-23 Engine Control Dial Output Control............................T2-2-25 Speed Sensing Control ....................................................T2-2-27 Output Power Control......................................................T2-2-30 ECO/PWR Mode Control..................................................T2-2-32 Relief Flow Rate Decrease Control...............................T2-2-34 Swing High Pressure Power Decrease Control........T2-2-36 Overheat Prevention Control ........................................T2-2-38 Attachment Operation Pump Control (Option)......T2-2-40 Radiator Fan Pump Flow Rate Control (Air Conditioner Switch: OFF)...........................................T2-2-42 Radiator Fan Pump Flow Rate Control (Air Conditioner Switch: ON) ............................................T2-2-44 Pump and Valve Learning Control...............................T2-2-46 Pump Torque Restriction Control ................................T2-2-48 Valve Control (Standard) .................................................T2-2-50 Valve Control (Standard) System Layout...................T2-2-51 Pressure Rising Selection Control When Traveling. .............................................................................................T2-2-52 Power Digging Control ....................................................T2-2-54 Auto-Power Lift Control...................................................T2-2-56 Travel Motor Displacement Angle Control ...............T2-2-58 Boom Mode Selector Control........................................T2-2-60 Swing Flow Rate Control .................................................T2-2-62

TOJBQ40-EN-00(07/02/2020)

Arm 2 Flow Rate Control .................................................T2-2-64 Bucket Flow Combiner Control.....................................T2-2-66 Aftertreatment Device Manual Regeneration Control..............................................................................T2-2-68 Aftertreatment Device Auto Regeneration Control .............................................................................................T2-2-70 Engine Protection Control at Low Temperature.....T2-2-72 Oil Cooler Fan Rotation Control....................................T2-2-74 Radiator Fan and Oil Cooler Fan Reverse Rotation Control..............................................................................T2-2-76 Arm Regenerative Cut Control......................................T2-2-77 Other Control ......................................................................T2-2-80 Auto Shut-Down Control ................................................T2-2-80 Hydraulic Oil Overheat Alarm Control .......................T2-2-82 Engine Oil, Coolant Level Check Control...................T2-2-82 Auto-Lubrication Control (Option)..............................T2-2-83 Breaker Alarm Control (Option)....................................T2-2-85 Overload Alarm Control (Option).................................T2-2-86

Engine System ..........................................T2-3-1 Outline of ECM System ...................................................... T2-3-1 Fuel Injection Control......................................................... T2-3-2 Fuel Injection Amount Control ....................................... T2-3-3 Fuel Injection Timing Control.......................................... T2-3-6 Fuel Injection Rate Control............................................... T2-3-8 Fuel Injection Pressure Control....................................... T2-3-9 Fuel Injection Amount Correction Control...............T2-3-11 EGR Control..........................................................................T2-3-13 Preheating Control ............................................................T2-3-15 Variable Turbocharger Control .....................................T2-3-16 Alarm Control......................................................................T2-3-17 Urea SCR System ................................................................T2-3-17 DEF Injection Control .......................................................T2-3-18 Start-Up Control .................................................................T2-3-19 DEF Defrosting Control....................................................T2-3-20 DEF Thermal Control ........................................................T2-3-21 After-Run Control...............................................................T2-3-23 Engine Output Restriction Control (INDUCEMENT) .............................................................................................T2-3-24 Insufficient DEF Level .......................................................T2-3-25 Malfunction of Urea SCR System/Malfunction of EGR System.....................................................................T2-3-25 Outline of Aftertreatment Device................................T2-3-26 Operation of Aftertreatment Device...........................T2-3-27 Aftertreatment Device Regeneration Control.........T2-3-29

Hydraulic System ......................................T2-4-1 Outline of Hydraulic System ............................................ T2-4-1 Pilot Circuit of Hydraulic System .................................... T2-4-1 Operation Control Circuit.................................................. T2-4-3 Pump Control Circuit (Refer to COMPONENT OPERATION/Pump Device.) ........................................ T2-4-4 Aftertreatment Device Regeneration Control Circuit (Refer to SYSTEM/Control System.)............ T2-4-5 Bucket Flow Combiner Circuit (Refer to SYSTEM/ Control System.).............................................................. T2-4-6 Valve Control Circuit (Refer to COMPONENT OPERATION/Control Valve.) ........................................ T2-4-7 Travel Motor Displacement Angle Control Circuit (Refer to COMPONENT OPERATION/Travel Device.).............................................................................T2-4-10 Swing Parking Brake Release Circuit (Refer to COMPONENT OPERATION/Swing Device.)..........T2-4-12 Emergency Boom Lower Circuit (Refer to COMPONENT OPERATION/Others (Upperstructure).).........................................................T2-4-13 Main Circuit of Hydraulic System .................................T2-4-15 Neutral Circuit .....................................................................T2-4-17 Flow Combiner Circuit .....................................................T2-4-18 Relief Circuit.........................................................................T2-4-20 Combined Operation Circuit .........................................T2-4-22 Flow Combiner Circuit .....................................................T2-4-24 Swing Flow Rate Control Circuit...................................T2-4-26 Arm Regenerative Cut Circuit........................................T2-4-28 Arm 1 Flow Rate Control Circuit ...................................T2-4-30 Arm 2 Flow Rate Control Circuit ...................................T2-4-32 Bucket Regenerative Cut Circuit...................................T2-4-34 Boom Lower Meter-In Cut Control ..............................T2-4-36 Boom Cylinder Bottom Pressure: High (With the Front Attachment above the Ground)..................T2-4-36 Boom Cylinder Bottom Pressure: Low (With Track Raised off the Ground) ...............................................T2-4-38 Radiator and Oil Cooler Fan Reverse Rotation Control Circuit................................................................T2-4-40

Electrical System.......................................T2-5-1 Outline of Electrical System ............................................. T2-5-1 Main Circuit of Electrical System .................................... T2-5-1 Electric Power Circuit (Key Switch: OFF) ...................... T2-5-1 CAN Circuit ............................................................................. T2-5-3 Accessory Circuit (Key Switch: ACC).............................. T2-5-4 Starting Circuit (Key Switch: START).............................. T2-5-5 Charging Circuit (Key Switch: ON) ................................. T2-5-7 Alternator Operation .......................................................... T2-5-8 Regulator Operation........................................................... T2-5-9 Surge Voltage Prevention Circuit ................................... T2-5-9 Pilot Shut-Off Circuit (Key Switch: ON).......................T2-5-10 Auto Shut-Down Circuit/Automatic Engine Stop Circuit at Low Temperature ......................................T2-5-11 Engine Stop Circuit............................................................T2-5-13 Emergency Stop Circuit...................................................T2-5-14 Monitor Circuit of Electrical System ............................T2-5-16 TOJBQ40-EN-00(07/02/2020)

Security Circuit....................................................................T2-5-17 Aerial Angle Circuit............................................................T2-5-18 Control Lever Automatic Pilot Shut-Off Circuit.......T2-5-18 Seat Belt Reminder Circuit..............................................T2-5-19 Radio Circuit.........................................................................T2-5-20 Air Conditioner Circuit .....................................................T2-5-21 Accessory Circuit................................................................T2-5-22 Work Light Circuit (Work Light: ON)............................T2-5-22 Work Light Circuit (Work Light, Work Light (Cab Upper), and Boom Light: ON) ..................................T2-5-24 Wiper Circuit ........................................................................T2-5-26 Washer Circuit .....................................................................T2-5-28 Cab Light Circuit (Cab Light Switch: Door Interlocking Position (Key Switch: ON))................T2-5-30 Cab Light Circuit (Cab Light Switch: ON Position)... .............................................................................................T2-5-31

COMPONENT OPERATION Pump Device .............................................T3-1-1 Outline of Pump Device .................................................... T3-1-1 Outline of Main Pump........................................................ T3-1-2 Operational Principle of Main Pump ............................ T3-1-2 Increasing and Decreasing of Main Pump Delivery Flow Rate........................................................................... T3-1-3 Outline of Regulator (For Main Pump) ......................... T3-1-3 Control by Pump Control Solenoid Valve (Minimum Flow Rate).................................................... T3-1-5 Control by Pump Control Solenoid Valve (Increase of Flow Rate)..................................................................... T3-1-6 Control by Pump Control Solenoid Valve (Decrease of Flow Rate)................................................ T3-1-7 Outline of Pump Control Solenoid Valve .................... T3-1-8 Operation of Pump Control Solenoid Valve (When in Neutral) ......................................................................... T3-1-8 Operation of Pump Control Solenoid Valve (When Excited)............................................................................... T3-1-8 Outline of Radiator Fan Pump......................................... T3-1-9 Operational Principle of Radiator Fan Pump ............. T3-1-9 Increasing and Decreasing of Radiator Fan Pump Delivery Flow Rate .......................................................T3-1-10 Outline of Regulator (For Radiator Fan Pump)........T3-1-11 Control by Fan Pump Control Solenoid Valve (Minimum Flow Rate)..................................................T3-1-12 Control by Fan Pump Control Solenoid Valve (Increase of Flow Rate) ...............................................T3-1-13 Control by Fan Pump Control Solenoid Valve (Decrease of Flow Rate)..............................................T3-1-14 Outline of Fan Pump Control Solenoid Valve ..........T3-1-15 Operation of Fan Pump Control Solenoid Valve (When in Neutral).........................................................T3-1-16 Operation of Fan Pump Control Solenoid Valve (When Excited) ..............................................................T3-1-16 Outline of Pilot Pump and Oil Cooler Fan Pump ....T3-1-17 Outline of Pump Delivery Pressure Sensor...............T3-1-17 Outline of Pump Displacement Control Pressure Sensor...............................................................................T3-1-18

Swing Device.............................................T3-2-1 Outline of Swing Device.................................................... T3-2-1 Outline of Swing Reduction Gear .................................. T3-2-1 Outline of Swing Motor ..................................................... T3-2-2 Outline of Swing Parking Brake ...................................... T3-2-4 When Brake is Released of Swing Parking Brake...... T3-2-4

TOJBQ40-EN-00(07/02/2020)

When Brake is Applied of Swing Parking Brake ........ T3-2-4 Outline of Valve Unit........................................................... T3-2-5 Operation of Make-Up Valve ........................................... T3-2-5 Outline of Swing Relief Valve........................................... T3-2-7 Low-Pressure Relief Operation (Shockless Function) of Swing Relief Valve................................. T3-2-7 High-Pressure Relief Operation (Overload Prevention) of Swing Relief Valve............................. T3-2-7

Control Valve.............................................T3-3-1 Outline of Control Valve .................................................... T3-3-1 Components in Control Valve ......................................... T3-3-2 Main Circuit of Control Valve .........................................T3-3-13 Pilot Operation Control Circuit of Control Valve.....T3-3-14 External Pilot Pressure Circuit of Control Valve.......T3-3-16 Operation of Flow Combiner Valve .............................T3-3-17 Outline of Main Relief Valve ...........................................T3-3-20 Relief Operation of Main Relief Valve .........................T3-3-20 Pressure Increasing Operation of Main Relief Valve .............................................................................................T3-3-21 Outline of Overload Relief Valve (With Make-Up Function) .........................................................................T3-3-22 Relief Operation of Overload Relief Valve.................T3-3-22 Make-Up Operation of Overload Relief Valve..........T3-3-23 Outline of Boom Overload Relief Valve (Low Pressure) ..........................................................................T3-3-23 Relief Operation of Boom Overload Relief Valve (Low Pressure)................................................................T3-3-24 Make-Up Operation of Boom Overload Relief Valve (Low Pressure)....................................................T3-3-25 Outline of Regenerative Valve.......................................T3-3-26 Operation of Boom Regenerative Valve ....................T3-3-26 Outline of Bucket Regenerative Valve........................T3-3-28 Operation When Performing Bucket Regenerative Operation ........................................................................T3-3-28 Operation When Performing Bucket Regenerative Cut Operation ................................................................T3-3-29 Operation When Performing Arm Regenerative Operation ........................................................................T3-3-30 Operation When Performing Arm Regenerative Cut Operation ................................................................T3-3-32 Outline of Anti-Drift Valve ..............................................T3-3-35 Holding Operation of Anti-Drift Valve........................T3-3-35 Releasing Operation of Anti-Drift Valve.....................T3-3-36 Outline of Flow Rate Control Valve..............................T3-3-36 Normal Operation of Flow Rate Control Valve ........T3-3-37

Flow Rate Control Operation of Flow Rate Control Valve..................................................................................T3-3-38 Outline of Boom Lower Meter-In Cut Valve..............T3-3-40 Operation of Boom Lower Meter-In Cut Valve (With the Track off the Ground) ..............................T3-3-42 Operation of Boom Lower Meter-In Cut Valve (With the Front Attachment above the Ground) .............................................................................................T3-3-44 Operation of Auxiliary Flow Combiner Valve (Auxiliary Flow Combiner Valve: OFF)...................T3-3-47 Operation of Auxiliary Flow Combiner Valve (Auxiliary Flow Combiner Valve: ON) ....................T3-3-48 Outline of Pump 1 Bypass Shut-Out Valve and Pump 2 Bypass Shut-Out Valve ...............................T3-3-49 Operation of Pump 1 Bypass Shut-Out Valve..........T3-3-51 Operation of Pump 2 Bypass Shut-Out Valve..........T3-3-53

Pilot Valve .................................................T3-4-1 Outline of Pilot Valve .......................................................... T3-4-1 Outline of Front Attachment/Swing Pilot Valve ....... T3-4-1 Outline of Travel Pilot Valve ............................................. T3-4-2 Outline of Auxiliary Pilot Valve........................................ T3-4-2 Operation of Front Attachment/Swing and Travel Pilot Valves........................................................................ T3-4-3 When Front Attachment/Swing and Travel Pilot Valves are in Neutral (Output Curve: A to B)......... T3-4-4 During Metering or Decompressing of Front Attachment/Swing and Travel Pilot Valves (Output Curve: C to D) .................................................. T3-4-6 Full Stroke of Front Attachment/Swing and Travel Pilot Valves (Output Curve: E to F)............................ T3-4-8 Operation of Auxiliary Pilot Valve .................................. T3-4-9 When Auxiliary Pilot Valve are in Neutral (Output Curve: A to B).................................................................... T3-4-9 During Metering or Decompressing of Auxiliary Pilot Valve (Output Curve: C to D) ..........................T3-4-10 Outline of Shockless Function (Only Travel Pilot Valve) ................................................................................T3-4-12 Operation of Shockless Function .................................T3-4-12

Travel Device.............................................T3-5-1 Outline of Travel Device .................................................... T3-5-1 Outline of Travel Reduction Gear................................... T3-5-2 Outline of Travel Motor...................................................... T3-5-3 Operation of Travel Motor ................................................ T3-5-3 Outline of Parking Brake ................................................... T3-5-4 Operation of Parking Brake (When Parking Brake is Released) ....................................................................... T3-5-5 Operation of Parking Brake (When Parking Brake is Applied) ......................................................................... T3-5-6 Outline of Travel Brake Valve ........................................... T3-5-7 Operation of Counterbalance Valve (During Travel) ................................................................................. T3-5-8 Operation of Counterbalance Valve (When Descending a Slope) ..................................................... T3-5-9 Outline of Travel Relief Valve .........................................T3-5-11

TOJBQ40-EN-00(07/02/2020)

Operation of Travel Relief Valve (During Relief ) .....T3-5-11 Operation of Travel Relief Valve (During Make-Up) .............................................................................................T3-5-11 Outline of Travel Mode Control ....................................T3-5-13 Operation of Selecting Travel Mode (Slow Speed). .............................................................................................T3-5-13 Operation of Selecting Travel Mode (Fast Speed)... .............................................................................................T3-5-13

Signal Control Valve .................................T3-6-1 Outline of Signal Control Valve....................................... T3-6-1 Pilot Valve Side of Pilot Port ............................................. T3-6-1 Control Valve Side of Pilot Port ....................................... T3-6-2 Outline of Shuttle Valve..................................................... T3-6-3 Outline of Shockless Valve................................................ T3-6-6 Operation of Shockless Valve (During Boom Raise Operation)......................................................................... T3-6-6 Operation of Shockless Valve (During Boom Lower Operation or When Stopping Boom Raise Operation (Shock Reducing Operation))... ............................................................................................... T3-6-7 Operation of Flow Combiner Valve Control Spool.. ............................................................................................... T3-6-9 Operation of Swing Parking Brake Release Spool... .............................................................................................T3-6-10 Operation of Arm Flow Rate Control Valve Control Spool.................................................................................T3-6-10

Others (Upperstructure) ..........................T3-7-1 Outline of Pilot Shut-Off Solenoid Valve ..................... T3-7-1 Pilot Shut-Off Lever: LOCK Position............................... T3-7-2 Pilot Shut-Off Lever: UNLOCK Position......................... T3-7-2 Outline of Solenoid Valve ................................................. T3-7-3 Outline of 4-Spool Solenoid Valve Unit (Control Valve Side)......................................................................... T3-7-3 Outline of 4-Spool Solenoid Valve Unit (Hydraulic Oil Tank Side).................................................................... T3-7-4 Outline of Proportional Solenoid Valve ....................... T3-7-5 Operation of Proportional Solenoid Valve (When in Neutral) ......................................................................... T3-7-5 Operation of Proportional Solenoid Valve (When Excited)............................................................................... T3-7-5 Outline of Radiator Fan Motor ........................................ T3-7-6 Outline of Radiator Fan Valve .......................................... T3-7-6 Relief Operation of Radiator Fan Valve ........................ T3-7-7 Make-Up Operation of Radiator Fan Valve ................. T3-7-8 Outline of Oil Cooler Fan Motor...................................... T3-7-9 Outline of Oil Cooler Fan Valve ....................................... T3-7-9 Outline of ON/OFF Solenoid Valve ..............................T3-7-11 Operation of ON/OFF Solenoid Valve (when in Neutral) ............................................................................T3-7-11 Operation of ON/OFF Solenoid Valve (When in Operation).......................................................................T3-7-11 Outline of Pilot Relief Valve ............................................T3-7-12 Outline of Recirculation Valve .......................................T3-7-13 Outline of Shockless Valve..............................................T3-7-13

Operation of Shockless Valve ........................................T3-7-14 Outline of Accumulator (Pilot Circuit) ........................T3-7-15 Outline of Distribution Valve .........................................T3-7-16 Operation of Distribution Valve....................................T3-7-16

Others (Undercarriage) ............................T3-8-1 Outline of Swing Bearing .................................................. T3-8-1 Outline of Center Joint....................................................... T3-8-1 Outline of Track Adjuster .................................................. T3-8-2

TOJBQ40-EN-00(07/02/2020)

MEMO

TOJBQ40-EN-00(07/02/2020)

Component Specifications.......................T1-3-1 TOJBQ40-EN-00(07/02/2020)

MEMO

TOJBQ40-EN-00(07/02/2020)

SECTION1 GENERAL Group1 Specifications Specifications ZX690LCH-7, 690LCR-7 A C

L B

E D K

J H

MJAQ-12-003-1 ja

Model

ZX690LCH-7

ZX690LCR-7

3.6 m H Arm

3.6 m R Arm

Type of Front-End Attachment

Bucket Capacity (Heaped)

PCSA 2.9, CECE 2.5

Counterweight Weight

10400

Operating Weight

69400

Base Machine Weight

54700

Engine Type

Engine Power

kW/min-1

70700 54900 Isuzu 6WG1

ISO 14396: 348/1800 ISO 9249: 345/1800

A : Overall Width (Excluding back mirrors)

4360

B : Cab Height

3660

C : Rear End Swing Radius

4020

D : Minimum Ground Clearance

*1860

E : Counterweight Clearance

*11530

F : Engine Cover Height

*13760

G : Overall Width of Upperstructure

4090

H : Undercarriage Length

5840

I : Undercarriage Width(Extended/Retracted)

3950/3480

J : Sprocket Center to Idler Center

4590

K : Track Shoe Width

650 (Double grouser shoe)

L : Overrail length

4230

Ground Pressure

kPa

Swing Speed

min-1

9.0

Travel Speed (fast/slow)

km/h

5.0/3.4

Gradeability

°(tanθ)

35(0.70)

NOTE *1The dimensions do not include the height of the shoe lug.

TOJBQ40-EN-00(07/02/2020)

T1-1-1

104

106

SECTION1 GENERAL Group1 Specifications Working Ranges ZX690LCH-7, 690LCR-7 G

TJBQ-01-01-001-1 ja

Category Item

Boom 6.8 m BE/ Boom 6.8 m BER

Boom 7.8 m H/ Boom 7.8 m R

Arm 2.9 m BE/Arm 2.9 m BER

Arm 3.6 m H/Arm 3.6 m R

A: Maximum Digging Reach

11800

13280

B: Maximum Digging Depth

*17120

*18560

C: Maximum Cutting Height

*111190

*111940

D: Maximum Dumping Height

*17330

*18020

E: Overall Height

4460

F: Overall Length

4230

G: Minimum Swing Radius

5240

5780

NOTE *1The dimensions do not include the height of the shoe lug.

TOJBQ40-EN-00(07/02/2020)

T1-1-2

SECTION1 GENERAL Group2 Component Layout Main Component (Upperstructure) 3 1 10 6 14

8 12 11

4 15

2 9 5

Upperstructure (1) TJBQ-01-02-001-1 ja 12345-

Engine Signal Control Valve Aftertreatment Device Swing Device DEF Tank

TOJBQ40-EN-00(07/02/2020)

6789-

4-Spool Solenoid Valve Unit (Control Valve Side) Intercooler Fuel Cooler DEF Supply Module

10111213-

T1-2-1

Expansion Tank Air Conditioner Condenser Fuel Tank Battery

1415-

4-Spool Solenoid Valve Unit (Hydraulic Oil Tank Side) Ambient Temperature Sensor

SECTION1 GENERAL Group2 Component Layout

20 23 24

16 18

Upperstructure (2) 1617-

Front Attachment/Swing Pilot Valve Pilot Shut-Off Solenoid Valve

TOJBQ40-EN-00(07/02/2020)

181920-

Travel Pilot Valve Air Cleaner Hydraulic Oil Tank

212223-

T1-2-2

Control Valve Pump Device Pilot Filter/Pilot Relief Valve

24-

TJBQ-01-02-002-1 ja Drain Filter

SECTION1 GENERAL Group2 Component Layout Main Component (Undercarriage)

1 2

7 6 5 4 3 12-

Swing Bearing Center Joint

TOJBQ40-EN-00(07/02/2020)

34-

Travel Device Lower Roller

56-

T1-2-3

Upper Roller Track Adjuster

TJBQ-01-02-011-1 ja Front Idler

SECTION1 GENERAL Group2 Component Layout Main Component (Front Attachment) 2 1

TJAQ-01-02-006-2 ja 1-

Bucket Cylinder

TOJBQ40-EN-00(07/02/2020)

Arm Cylinder

T1-2-4

Boom Cylinder

SECTION1 GENERAL Group2 Component Layout Electrical System (Overview) 18

1 2

20 19

7 5

8 23 16

22 6

13 4

11 10

1234567-

Rear view Camera (Refer to "Engine"T1-2-11) Camera Left Battery (Refer to "DEF Supply Mod ule"T1-2-19) (Refer to "Electrical System (Utility Space)"T1-2-8) (Refer to "Signal Control Valve"T1-2-14)

TOJBQ40-EN-00(07/02/2020)

91011121314-

(Refer to "4-Spool Solenoid Valve Unit (Control Valve Side)"T1-2-17) Wiper Motor Monitor Horn Work Light (Refer to "DEF Tank"T1-2-19) (Refer to "Swing De vice"T1-2-16)

151617181920-

T1-2-5

Fuel Sensor Hydraulic Oil Temperature Sensor (Refer to "Pump De vice"T1-2-13) (Refer to "Expansion Tank"T1-2-18) Camera Right (Refer to "Air Clean er"T1-2-18)

212223-

TJBQ-05-04-017-1 ja (Refer to "Aftertreatment De vice"T1-2-12) (Refer to "Control Valve"T1-2-14) (Refer to "4-Spool Solenoid Valve Unit (Hydraulic Oil Tank Side)"T1-2-17)

SECTION1 GENERAL Group2 Component Layout Electrical System (Rear Tray) 1

2 3 A

6 A

11 12 13 14

22 9 21

1234-

MC (Main Controller) Fuse Box 1 Fuse Box 2 MPDr. Connector (Download Connector Using Combined ly) DC-DC Converter

TOJBQ40-EN-00(07/02/2020)

67891011-

PLCU (Option) GSM (Communication Con troller) Monitor Controller Pilot Shut-Off Relay (R12) Horn Relay (R10) Work Light Relay 2 (R8)

12131415161718-

T1-2-6

Wiper Relay (R6) Starter Cut Relay (R4) ECM Main Relay (R2) Load Dump Relay (R1) Security Horn Relay (R3) Key Switch ON Cut Relay (R5) Work Light Relay 1 (R7)

1920212223-

TJAQ-05-04-022-1 ja Washer Relay (R9) ACC Cut Relay (R11) Auto-Lubrication Relay (R13) Fuel Pump Relay (R14) Aerial Angle Controller

SECTION1 GENERAL Group2 Component Layout Electrical System (Switches)

26 16 3

őŖŔŉ

˩ˡ˪˱ Ŕņŕ

18 ůİŮŪůġ

15 22

˩˫ˠˡ

őŖŔŉ

䰙

信 ŕŖŏņ

˩˫ˠˡ

䩩

őŖŔŉ

ŔŐŖœńņ

őŖŔŉ

ŗŐōİőŘœȁ

łŖŕŐ İŐŇŇ łŖŕŐ

ůİŮŪůġ

䢳䢴

ŐŇŇ

19 20

Ŋŏŕ

Őŏ őŖŔŉġ

ＯＦＦ

łń

ń Őŏ

Ŕŕł œŕ

25 9

0 Ŋŏŕ

Őŏ

ŐŇŇ őŖŔŉ

8 1234567-

Home Switch Select/Set Switch Engine Control Dial Power Mode Switch Source Switch/Tuning Switch Power Switch/Volume Control Switch Fresh/Re-Circulated Air Switch

891011121314-

Numeric Keypad Key Switch Wiper/Washer Switch Work Light Switch Travel Mode Switch Auto-Idle Switch AUTO/OFF Switch/Blower Switch

151617-

1819-

Temperature Control Switch/ Mode Switch Return to Previous Screen Switch Overhead Window Wiper/ Overhead Window Washer Switch (Option) Power Digging Switch Aerial Angle Switch

17 2021222324252627-

TJAQ-05-04-023-1 ja Manual Regeneration Switch Pilot Shut-Off Lever Horn Switch Boom Mode Selector Switch Auto-Lubrication Switch Fan Reverse Rotation Switch Audio Mute/One-Touch Idle Switch Quick Wiper Switch

NOTE Audio mute/one-touch idle switch (26) can be set to OFF, engine idle mode, radio mute mode, or engine idle/radio mute mode by the MPDr. (PBLI)

TOJBQ40-EN-00(07/02/2020)

T1-2-7

SECTION1 GENERAL Group2 Component Layout Electrical System (Utility Space) a

TJBQ-05-04-004-1 ja

a- Machine Front Side 1-

ECM (Engine Controller)

TOJBQ40-EN-00(07/02/2020)

DCU

T1-2-8

VGS Controller

SECTION1 GENERAL Group2 Component Layout Electrical System (Around Battery) A

8 A

5 6

1 12-

Battery Starter Relay

34-

7 Battery Relay Fusible Link (45A)

56-

Glow Plug Relay Fusible Link (80A, 120A)

78-

TJBQ-05-04-006-1 ja Battery Disconnect Switch Washer Tank

Engine Oil Monitoring Sensor and Engine Oil Filter a

1 2 TJBQ-05-04-020-1 ja

a- Machine Front Side 1-

Engine Oil Monitoring Sensor

TOJBQ40-EN-00(07/02/2020)

Engine Oil Filter

T1-2-9

SECTION1 GENERAL Group2 Component Layout Hydraulic Oil Monitoring Sensor a

1 TJBQ-05-04-021-1 ja

a- Machine Front Side 1-

Hydraulic Oil Monitoring Sen sor

TOJBQ40-EN-00(07/02/2020)

T1-2-10

SECTION1 GENERAL Group2 Component Layout Engine 16 14

12 3 5 1

7 2

17 12345678-

Overheat Switch Coolant Temperature Sensor Glow Plug Intake Throttle Common Rail Pressure Sensor Fuel Temperature Sensor Crank Speed Sensor Priming Pump

TOJBQ40-EN-00(07/02/2020)

18 910111213-

Engine Oil Pressure Sensor EGR Cooler Outlet Tempera ture Sensor 1 EGR Valve 1 Intake Manifold Temperature Sensor Boost Pressure/Temperature Sensor

141516171819-

T1-2-11

Injector Connector EGR Cooler Inlet Temperature Sensor 1 VGS Actuator Engine Oil Level Switch Cam Angle Sensor MAF/Intake-Air Temperature Sensor

202122-

TJAQ-05-04-018-1 ja EGR Valve 2 EGR Cooler Outlet Tempera ture Sensor 2 EGR Cooler Inlet Temperature Sensor 2

SECTION1 GENERAL Group2 Component Layout Aftertreatment Device 9

2 TJAQ-05-04-012-1 ja

a- Machine Front Side 123-

Differential Pressure Sensor Downstream NOx Sensor Controller Downstream NOx Sensor

TOJBQ40-EN-00(07/02/2020)

456-

Upstream NOx Sensor Con troller Dosing Module Upstream NOx Sensor

78-

T1-2-12

DOC Outlet Exhaust Tempera ture Sensor DOC Inlet Exhaust Tempera ture Sensor

910-

SCR Exhaust Temperature Sensor Differential Pressure Detec tion Port

SECTION1 GENERAL Group2 Component Layout Pump Device 1

3 2

10 1234-

Pump 1 Fan Pump Control Solenoid Valve Radiator Fan Pump Oil Cooler Fan Pump

TOJBQ40-EN-00(07/02/2020)

567-

Pilot Pump Pump 2 Pump 2 Delivery Pressure Sensor

89-

Pump 1 Delivery Pressure Sensor Pump 1 Displacement Control Pressure Sensor

101112-

T1-2-13

TJBQ-05-04-001-1 ja Pump 2 Displacement Control Pressure Sensor Pump 2 Control Solenoid Valve Pump 1 Control Solenoid Valve

SECTION1 GENERAL Group2 Component Layout Control Valve X

a a

6 4

X TJAQ-03-03-003-2 ja

a- Machine Upper Side 12-

Main Relief Valve Arm Roll-In Pilot Pressure Sen sor

b- Machine Front Side 3-

Bucket Roll-In Pilot Pressure Sensor

45-

Bucket Roll-Out Pilot Pressure Sensor Arm Roll-Out Pilot Pressure Sensor

67-

Boom Raise Pilot Pressure Sensor Boom Lower Pilot Pressure Sensor

Signal Control Valve 3

Control Valve Side TJAQ-05-04-006-1 ja

TOJBQ40-EN-00(07/02/2020)

T1-2-14

SECTION1 GENERAL Group2 Component Layout 1-

Travel Pilot Pressure Sensor

Swing Pilot Pressure Sensor

Attachment Pilot Pressure Sensor

A A-A A

TJAQ-05-04-007-1 ja

a- Pilot Valve Side 12-

Arm Flow Rate Control Valve Control Spool Shockless Valve

Pump 1 Flow Rate Control Valve

45-

Pump 2 Flow Rate Control Valve Flow Combiner Valve Control Spool

67-

Swing Parking Brake Release Spool Auxiliary

Pilot Check Valve 1 2 a

TJBQ-05-04-008-1 ja

a- Machine Front Side TOJBQ40-EN-00(07/02/2020)

T1-2-15

SECTION1 GENERAL Group2 Component Layout 1-

4-Spool Pilot Pressure Sensor

5-Spool Pilot Pressure Sensor

Pilot Check Valve

Swing Device 1

1 TJBQ-05-04-009-1 ja 1-

Swing Relief Valve

Travel Device 1

TJAQ-05-04-009-1 ja 1-

Counterbalance Valve

TOJBQ40-EN-00(07/02/2020)

Travel Relief Valve

T1-2-16

SECTION1 GENERAL Group2 Component Layout 4-Spool Solenoid Valve Unit (Control Valve Side) SC

TJAQ-05-04-010-1 ja

SC- 5-Spool Bypass Shut-Out Control Solenoid Valve (SC) SF- Boom Mode Selector Control Solenoid Valve (SF)

SI- Swing Flow Rate Control Solenoid Valve (SI) SG- Arm 2 Flow Rate Control Solenoid Valve (SG)

4-Spool Solenoid Valve Unit (Hydraulic Oil Tank Side) SC

TJAQ-05-04-010-1 ja

SC- Travel Motor Displacement Angle Control Solenoid Valve (SC) SF- Main Relief Valve Control Solenoid Valve (SF)

TOJBQ40-EN-00(07/02/2020)

SI- Arm Regenerative Control Solenoid Valve (SI) SG- 4-Spool Bypass Shut-Out Control Solenoid Valve (SG)

T1-2-17

SECTION1 GENERAL Group2 Component Layout Expansion Tank 1

TJBQ-05-04-007-1 ja 1-

Expansion Tank

Coolant Level Switch

Air Cleaner Restriction Switch

Air Cleaner

1 2 TJBQ-05-04-018-1 ja 1-

Air Cleaner

TOJBQ40-EN-00(07/02/2020)

T1-2-18

SECTION1 GENERAL Group2 Component Layout DEF Tank 1 5

123-

DEF Sensor Unit DEF Tank Coolant Hose (From Engine)

DEF Hose (To DEF Supply Module)

56-

Coolant Hose (From DEF Sup ply Module) DEF Hose (From DEF Supply Module)

78-

TJBQ-05-04-002-1 ja DEF Tank Level Sensor DEF Tank Temperature / DEF Quality Sensor

DEF Supply Module

2 TJBQ-05-04-005-1 ja

DEF Supply Module

TOJBQ40-EN-00(07/02/2020)

DEF Supply Module Main Fil ter

T1-2-19

SECTION1 GENERAL Group2 Component Layout Coolant Control Valve

TJBQ-05-04-019-1 ja 1-

Coolant Control Valve

Electric Fuel Pump and Fuel Filter

2 TJBQ-05-04-022-1 ja

a- Machine Front Side 1-

Electric Fuel Pump

TOJBQ40-EN-00(07/02/2020)

Fuel Pre-Filter

T1-2-20

Fuel Filter

SECTION1 GENERAL Group2 Component Layout Radiator Fan Valve and Radiator Fan Motor

1 TJBQ-01-02-005-1 ja 1-

Radiator Fan Valve

TOJBQ40-EN-00(07/02/2020)

Radiator Fan Motor

T1-2-21

SECTION1 GENERAL Group2 Component Layout Oil Cooler Fan Valve and Oil Cooler Fan Motor 2

TJBQ-01-02-004-1 ja 1-

Oil Cooler Fan Valve

Oil Cooler Fan Motor

Shockless Valve

1 TJBQ-01-02-003-1 ja

a- Machine Front Side 1-

Shockless Valve

TOJBQ40-EN-00(07/02/2020)

T1-2-22

SECTION1 GENERAL Group2 Component Layout Radiator Fan Valve 2

3 TJAQ-01-02-011-1 ja 1-

Radiator Fan Valve

Fan Reverse Rotation Control Solenoid Valve 1

Relief Valve

Oil Cooler Fan Valve 1

4 2

Fan Reverse Rotation Control Solenoid Valve 2

TOJBQ40-EN-00(07/02/2020)

Oil Cooler Fan Control Valve

T1-2-23

Fan Speed Control Solenoid Valve

TJBQ-05-04-011-1 ja Reverse Rotation Spool

SECTION1 GENERAL Group2 Component Layout Boom Upper Area 1

TJBQ-05-04-015-1 ja 1-

Distribution Valve (Boom)

Arm Upper Area 1

TJBQ-01-02-008-1 ja 1-

Distribution Valve (Arm)

TOJBQ40-EN-00(07/02/2020)

T1-2-24

SECTION1 GENERAL Group2 Component Layout Distribution Valve (Upperstructure) 3 2

TJBQ-05-04-013-1 ja 1-

Distribution Valve (Upper structure)

23-

Proximity Switch Horn

Auto-Lubrication Device 2

3 TJBQ-05-04-016-1 ja 1-

Lubrication Switching Valve Lever

TOJBQ40-EN-00(07/02/2020)

23-

Grease Pump Pail

T1-2-25

SECTION1 GENERAL Group2 Component Layout MEMO

TOJBQ40-EN-00(07/02/2020)

T1-2-26

SECTION1 GENERAL Group3 Component Specifications Specifications of Engine Manufacturer

ISUZU

Model

6WG1

Type

Diesel, 4-cycle, water-cooled, direct injection type, exhaust turbo charged type

Cyl. No.- Bore x Stroke

6-147 mm x 154 mm

Piston Displacement

15681 cm3

Rated Output

348 kW/1800 min-1

Compression Ratio

16.5

Dry Weight

1150 kg

Firing Order

1-5-3-6-2-4

Rotation Direction

Clockwise (Viewed from fan side)

Cooling System

Cooling Fan

Dia. 1120 mm, draw-in type, 6 blades, hybrid Dia. 850 mm, draw-in type, 6 blades, hybrid

Thermostat

Cracking temperature at atmospheric pressure: 76.5 °C Full open (stroke: 10 mm or more): 90 °C

Water Pump

Centrifugal type, gear driven

Lubrication Pump Type

Gear pump

Oil Filter

Full-flow paper element type and partial-flow paper element type

Oil Cooler

Water cooled integral 8-stage type

Motor

Magnetic pinion shift reduction type

Voltage/Output

24 V/7 kW

Preheat System

Method

Glow plug (24 V, QOS II type)

Engine Stop System

Method

Fuel shut-off (electronic control)

Alternator

Method

Regulator integrated AC type, brushless

Voltage/Output

24 V/90 A

Supercharging System

Type

Exhaust-turbocharger type, RHG 8 V

Fuel System

Type

Common rail type 6UHD type

Governor

Electronic all speed control

Injection Nozzle

Electrical multi-hole injector (G3 type)

Lubrication System

Starting System

IMPORTANT This list shows design specifications, which are not servicing standards. Perform ance (When New)

Fuel Consumption Ratio

214 g/kW·h

Maximum Output Torque

2050 N·m@1300 min-1

Compression Pres sure

2.94 MPa@200 min-1

Valve Clearance (In 0.4/0.4 mm (when cool) take/Exhaust) No Load Speed

Slow: 900 min-1 Fast: 1850 min-1

TOJBQ40-EN-00(07/02/2020)

T1-3-1

SECTION1 GENERAL Group3 Component Specifications Engine Performance Curve (6WG1) Test Condition: 1. In conformity with JIS D0006 (Performance Test Method for Diesel Engine Used for Construction Machinery) under standard atmospheric pressure. 2. Equipped with the alternator. 1yP

N: 3

J N:K

PLQ

TJBQ-01-03-001-1 ja

N- Engine Speed P- Output

q- Fuel Consumption Ratio T- Torque

Specifications of Engine Accessories Radiator Assembly

Type

Radiator and Oil Cooler Parallel Type, Intercooler Linear Type Radiator

Oil Cooler

Air-Tight Test Pressure

0.1 MPa

Expansion Tank

Total Capacity

17 L

Cap Opening Pressure

50 kPa

TOJBQ40-EN-00(07/02/2020)

1.5 MPa

T1-3-2

Intercooler 0.3 MPa

SECTION1 GENERAL Group3 Component Specifications Fuel Cooler Battery

Electric Fuel Pump

Fin Shape

Wavy fin

Capacity

0.44 L

Type

195G51

Voltage

12 V

Capacity

140 Ah or more (5-hour rate), 147 Ah or more (20-hour rate)

CCA

930 A

Rated Voltage

DC24 V

Specifications of Hydraulic Component Pump Device

Drive Gear Ratio

Main pump (P1, P2): 53/57, radiator fan pump: 1, oil cooler fan pump: 1, pilot pump: 1

Main Pump

Type

Swash plate type variable displacement axial plunger pump

Theoretical Displacement

300 cm3/rev ×2

Rated Pressure

31.9 MPa

Regulator

Type

Solenoid valve type

Radiator Fan Pump

Type

Swash plate type variable displacement plunger pump

Theoretical Displacement

63 cm3/rev

Type

Solenoid valve type

Regulator

Oil Cooler Fan Pump/Pilot Type Pump Theoretical Displacement

Fixed displacement type gear pump

Control Valve

Type

Pilot pressure operated type (4-spool + 5-spool)

Main Relief Set Pressure

Normal: 31.9+2.00 MPa@440 L/min

27.8 cm3/rev

Power digging: 34.3+2.00 MPa@430 L/min Overload Relief Set Pressure

35.3+1.00 MPa@110 L/min (boom, arm, bucket) 35.3+1.00 MPa@110 L/min (auxiliary close) 35.3+1.00 MPa@110 L/min (auxiliary open)

Swing Device Swing Motor Valve Unit Swing Parking Brake Travel Device Travel Motor

Travel Brake Valve

Type

Two-stage reduction planetary gear

Reduction Gear Ratio

23.63

Type

Swash plate type fixed displacement axial plunger motor

Theoretical Displacement

129.2 cm3/rev

Type

Non counterbalance valve type

Relief Set Pressure

29.4 MPa@88 L/min

Type

Wet-type spring set hydraulic released multi-disc brake

Release Pressure

3.7 MPa

Type

Three-stage reduction planetary gear

Reduction Gear Ratio

79.143

Type

Swash plate type variable displacement axial plunger motor

Theoretical Displacement (Fast/Slow)

228.6/337.2 cm3/rev

Type

Counterbalance valve type

Relief Set Pressure

36.8 MPa@120 L/min

TOJBQ40-EN-00(07/02/2020)

T1-3-3

SECTION1 GENERAL Group3 Component Specifications Travel Parking Brake

Type

Wet-type spring set hydraulic released multi-disc brake

Release Starting Pressure

1.37 MPa

Front Attachment/Swing Pilot Valve

Plunger Stroke

Ports 1, 3: 6.5 mm

Travel Pilot Valve

Plunger Stroke

Ports 1, 2, 3, 4: 4.6 mm

4-Spool Solenoid Valve Unit

Type

4-spool proportional solenoid valve

Rated Voltage

24 V DC

Coil Resistance

22 Ω

Signal Control Valve

Rated Pressure

3.72 MPa

Pilot Shut-Off Solenoid Valve

Type

ON/OFF Solenoid Valve

Rated Voltage

24 V DC

Coil Resistance

49 Ω

Pump Control Solenoid Valve

Rated Voltage

24 V DC

Coil Resistance

15 Ω

Fan Pump Control Sole noid Valve

Rated Voltage

24 V DC

Coil Resistance

17.5 Ω

Radiator Fan Motor

Type

Piston motor

Theoretical Displacement

48 cm3/rev

Type

Piston motor

Theoretical Displacement

28.2 cm3/rev

Relief Set Pressure

21.6 MPa@44.5 L/min

Oil Cooler Fan Motor Radiator Fan Valve

Ports 2, 4: 8.0 mm

Maximum Passing Flow Rate 98 L/min Low Pressure Relief Valve Relief Set Pressure

0.1 MPa

Bypass Check Valve

0.34 MPa

Relief Set Pressure

Cylinder

Boom

Arm

Bucket

Rod Outer Diameter

130 mm

140 mm

130 mm

Tube Inner Diameter

190 mm

200 mm

180 mm

Stroke

1805 mm

2165 mm

1555 mm

Fully Retracted Length 2600 mm

2970 mm

2385 mm

Plating Thickness

30 μm

Specifications of Electrical Component Battery Relay

Voltage/Current

24 V/100 A

Starter Relay

Voltage

24 V

Glow Plug Relay

Voltage

24 V

Engine Oil Level Switch

Type

Float lead switch

Overheat Switch

Operating Temperature

105±2 °C

Coolant Level Switch

Type

Float lead switch

Fuel Sensor

Resistance Value

Empty: 80+12+2 Ω Full: 100-4 Ω

Hydraulic Oil Temperature Operating Temperature Sensor

-30 to 120 °C

TOJBQ40-EN-00(07/02/2020)

T1-3-4

SECTION1 GENERAL Group3 Component Specifications Air Cleaner Restriction Switch

Operating Pressure

6.2±0.6 kPa

Horn

Voltage/Current

24 V/2.5 A

Sound Pressure

115±5 dB (A)@2 m

Work Light

LED 12 to 24V, 20W

Cab Light

LED 24 V/0.03 A

Refrigerant

HFC134 a

Cooling Ability

4.5 kW or more

Cool Air Volume

550 m3/h or more

Heating Ability

5.49 kW or more

Warm Air Volume

340 m3/h or more

Temperature Adjusting System

Electronic type

Refrigerant Quantity

1050±50 g

Compressor Oil Quantity

180 cm3

Illumination Air Conditioner

TOJBQ40-EN-00(07/02/2020)

T1-3-5

SECTION1 GENERAL Group3 Component Specifications MEMO

TOJBQ40-EN-00(07/02/2020)

T1-3-6

TOJBQ40-EN-00(07/02/2020)

SECTION2 SYSTEM Group1 Controller Outline of Controller The following controllers are provided in this machine in order to control the functions. Each controller excluding the communication controller communicates by using the CAN circuit and sends or receives the required signal. Controller

Control

Comment on Control

MC controls the engine, pumps, and valves.

T2-2

ECM

ECM controls the actual engine speed.

T2-3

VGS Controller

The VGS controller controls the engine turbocharger.

T2-3

DCU

DCU controls the DEF injection amount.

T2-3

Monitor Controller

The monitor controller displays the operating information and alarms on T2-5, T5-2 the monitor. The monitor controller controls the wipers and work lights.

Air Conditioner Controller

The air conditioner controller controls the air conditioner.

T2-5, T5-7

Radio Controller

The radio controller controls the radio.

T2-5

Communication Controller

The communication controller sends the mails and operating informa tion.

T5-3

Aerial Angle Controller

The aerial angle controller controls the composition/display switching of T2-5 camera images.

Switch Box Controller

The switch box controller sends the information on each switch.

T2-2, T2-5

PLCU (Option)

PLCU (Option) controls AFL.

NOTE Refer to the corresponding group for details of each controller control.

CAN Circuit CAN (Controller Area Network) is ISO Standards of the serial communication protocol. This machine has seven networks (CAN bus (4)) that consist of Power-CAN (1), Body-CAN (5), ISO-CAN (18), Local-CAN (20), IF-CAN (26), PL-CAN (22), and OPT-CAN (27). Power-CAN (1) and ISO-CAN (18) are used for the engine control. Body- CAN (5) is used for the accessories. Local-CAN (20) is used for the urea SCR system. IF-CAN (26) is used for communication. PL-CAN (22) is used for the AFL. OPT-CAN (27) is used for the oil monitoring sensor. CAN bus (4) consists of two harnesses, CAN-H (High) (2) and CAN-L (Low) (3). Each controller judges the CAN bus (4) level due to the potential difference between CAN-H (High) (2) and CAN-L (Low) (3). Each controller arranges the CAN bus (4) level and sends the signal and data to other controllers. Termination resistors (120 Ω) (17) are installed to both ends of CAN bus (4).

TOJBQ40-EN-00(07/02/2020)

T2-1-1

SECTION2 SYSTEM Group1 Controller 2 4 3 17

6 VGS

18 9

17 19 DCU

26 17

17 1

7 ECM

24 17

11 MPDr.

17 5 16

8 MC

17 27

22 17 17

25 PLCU

30 SW-BOX

17 29

14 28

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Power- CAN CAN-H (High) CAN-L (Low) CAN Bus Body- CAN VGS Controller (Variable Tur bo Controller) ECM (Engine Controller)

TOJBQ40-EN-00(07/02/2020)

89101112131415-

MC (Main Controller) Communication Controller Monitor Controller MPDr. Aerial Angle Controller Radio Controller Air Conditioner Controller Monitor Control Unit

1617181920212223-

T2-1-2

Information Control Unit Termination Resistor (120 Ω) ISO-CAN DCU Local-CAN DEF Sensor Unit PL-CAN Upstream NOx Sensor

24252627282930-

TDFY-02-01-001-1 ja Downstream NOx Sensor PLCU (Option) IF-CAN OPT-CAN Engine Oil Monitoring Sensor Hydraulic Oil Monitoring Sen sor Switch Box Controller

SECTION2 SYSTEM Group2 Control System Outline of Control System MC is used in order to control the machine operations. Signals from the engine control dial, various sensors, and various switches are sent to MC and processed in the logic circuit. MC sends the signal equivalent to the target engine speed to ECM by using CAN communication in order to control the engine. (Refer to SYSTEM/Engine System.) In addition, MC drives the solenoid valve unit and pump control solenoid valve in order to control the pump and valve.

Engine Control The engine control consists of the followings. ● Engine Protection Control ● Engine Control Dial Control ● ECO Control ● Power Mode (ECO/PWR/HP Mode) Switch Control ● ECO/PWR Mode Travel Speed Increase Control ● Auto-Idle Control ● Radiator Coolant Temperature Auto-Warming Up Control ● Engine Speed Slow Down Control ● One-Touch Idle Control (Option) ● Attachment Operation Speed Limit Control (Option)

TOJBQ40-EN-00(07/02/2020)

T2-2-1

SECTION2 SYSTEM Group2 Control System Engine Control System Layout 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

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T2-2-2

Pump 1 Control Solenoid Valve Pump 2 Displacement Control Pressure Sensor Pump 2 Control Solenoid Valve Pump 1 Displacement Control Pressure Sensor Auto Shut-Down Signal Travel Mode Switch Slow Speed Position Fast Speed Position Auto-Idle Switch Power Mode Switch Engine Control Dial

33343536373839404142-

TJAQ-02-02-001-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System Engine Protection Control Purpose: The engine protection control controls increasing the engine speed and promotes the circulation of the engine oil immediately after the engine starts. Therefore, the engine (turbocharger) is protected from being damaged.

TDC1-02-02-047-1 ja

A- Engine Speed B- Engine Control Dial Position C- Slow Idle Speed Position

D- Fast Idle Speed Position E- Slow Idle Speed F- Fast Idle Speed

Operation: 1. When the engine starts, MC (10) receives the signals from coolant temperature sensor (16), the hydraulic oil temperature sensor (1), and the engine oil pressure sensor (42). MC (10) sends the signal equivalent to the target engine speed according to the received signals to ECM (15) by using CAN communication (14). 2. ECM (15) sets the engine speed to slow idle speed and holds it for 5 to 26 seconds. 3. When the engine starts and the specified time is passed, MC (10) deactivates the engine protection control. 4. ECM (15) slowly returns the engine speed to the speed according to other engine controls.

NOTE The priority is given to the engine protection control. Therefore, the engine speed does not change even if engine control dial (32) is operated at the engine protection control. Other controls are activated after the engine protection control is deactivated.

TOJBQ40-EN-00(07/02/2020)

T2-2-3

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

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T2-2-4

33343536373839404142-

TJAQ-02-02-002-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System Engine Control Dial Control Purpose: The engine control dial control controls the engine speed according to the rotation angle of engine control dial (32).

TDC1-02-02-048-1 ja

A- Engine Speed B- Engine Control Dial Position C- Slow Idle Speed Position

D- Fast Idle Speed Position E- Fast Idle Speed F- Slow Idle Speed

Operation: 1. Switch box controller (39) receives the signals of the rotation angle (the required engine speed) of engine control dial (32) and sends the signals to MC (10) by using CAN communication (14). MC (10) sends the signal equivalent to the target engine speed according to the received signals to ECM (15) by using CAN communication (14). 2. ECM (15) controls the engine speed according to CAN communication (14).

TOJBQ40-EN-00(07/02/2020)

T2-2-5

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

T2-2-6

33343536373839404142-

TJAQ-02-02-003-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System ECO Control Purpose: The ECO control reduces the engine speed by 100 min-1 from the fast idle speed when all control levers are in neutral. Therefore, the fuel consumption and noise level can be reduced.

TDC1-02-02-049-1 ja

A- Engine Speed B- Engine Control Dial Position C- Slow Idle Speed Position D- Fast Idle Speed Position

E- Fast Idle Speed F- ECO Speed G- Slow Idle Speed

Operation: 1. When all following conditions exist and all the control levers are set to the neutral position [Pilot pressure sensors (2 to 9, 36 to 37): OFF], MC (10) sends the signal to ECM (15) by using CAN communication (14) after one second. •

Engine control dial (32): Fast idle speed position

•

Power mode switch (31): HP

2. ECM (15) reduces the engine speed by 100 min-1 from the fast idle speed.

NOTE The ECO control is deactivated by MPDr. (11) temporarily or completely. The ECO control is activated again when key switch (33) is turned OFF with the ECO control deactivated temporarily. (ECO Control Suspend) The ECO control is always deactivated with the ECO control deactivated completely. (ECO Control Selection) NOTE When the engine speed is set slower than the fast idle speed by 100 min-1 by engine control dial (32), the engine speed does not change. And the ECO control is done regardless of whether the auto-idle control is done or not. The fast idle speed can be corrected by MPDr. (11). (HP Mode Speed)

TOJBQ40-EN-00(07/02/2020)

T2-2-7

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

T2-2-8

33343536373839404142-

TJAQ-02-02-004-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System Power Mode (ECO/PWR/HP Mode) Switch Control Purpose: The power mode (ECO/PWR/HP mode) switch control shifts the power mode (ECO/PWR/HP mode) by operating power mode switch (31). Operation: 1. Switch box controller (39) receives the signal from power mode switch (31). 2. Switch box controller (39) sends the received signals to MC (10) by using CAN communication (14). 3. MC (10) shifts the power mode according to the setting of “Power Mode Selection“ and ”Power Mode Memory Selection” on MPDr. (11) by pushing power mode switch (31). (Refer to the table.) 4. MC (10) sends the signal equivalent to the target engine speed according to the received signals to ECM (15) by using CAN communication (14). 5. ECM (15) controls the engine speed according to CAN communication (14). 6. At the same time, MC (10) sends the control mode of power mode to monitor controller (12) by using CAN communication (14). 7. Monitor controller (12) displays the control mode of power mode on monitor (13). Power Mode Selection

Power Mode at the Mo ment When Key Switch is Turned OFF

Power Mode When Key Switch is ON Next Time Power Mode Memory Se lection: OFF

Power Mode Memory Se lection: ON

ECO

PWR

ECO mode: Fixed

ECO

PWR mode: Fixed

PWR

HP mode: Fixed

ECO/PWR Mode Selection

ECO

PWR

ECO/PWR/HP Mode Selection (De fault)

TOJBQ40-EN-00(07/02/2020)

T2-2-9

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

T2-2-10

33343536373839404142-

TJAQ-02-02-005-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System ECO/PWR Mode Travel Speed Increase Control Purpose: The ECO/PWR mode travel speed increase control increases the engine speed and makes the travel speed faster when performing the travel single operation in the ECO/PWR mode. F H I E

TJAQ-02-02-007-1 ja

A- Engine Speed

E- ECO Mode Engine Speed

B- Engine Control Dial Position

F- PWR Mode Engine Speed + 100 min-1 G- Slow Idle Speed H- PWR Mode Speed

C- Slow Idle Speed Position D- Fast Idle Speed Position

I- ECO Mode Engine Speed + 200 min-1

Operation: 1. When the engine speed is that set by the ECO/PWR mode control and power mode switch (31) is in the ECO/PWR mode position, MC (10) sends the signal equivalent to the target engine speed according to the travel control lever stroke to ECM (15) by using CAN communication (14). 2. ECM (15) increases the engine speed by 200 min-1 in the ECO mode or by 100 min-1 in the PWR mode compared to the speed set by the engine control dial control in order to make the travel speed faster.

TOJBQ40-EN-00(07/02/2020)

T2-2-11

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

T2-2-12

33343536373839404142-

TJAQ-02-02-008-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System Auto-Idle Control Purpose: The auto-idle control reduces the engine speed when all control levers are in neutral. Therefore, the fuel consumption and noise level can be reduced.

TDC1-02-02-052-1 ja

A- Engine Speed B- Engine Control Dial Position C- Slow Idle Speed Position D- Fast Idle Speed Position

E- Fast Idle Speed F- Auto-Idle Speed G- Slow Idle Speed

Operation: 1. When all following conditions exist, the auto-idle control is activated. •

Auto-idle switch (30): ON position

Control lever: All control levers are held in the neutral position [Pilot pressure sensors (2 to 9, 36 to 37): OFF] for 3.5 seconds or more 2. When the auto-idle control is activated, MC (10) sends the signal equivalent to the auto-idle speed to ECM (15) by using CAN communication (14). 3. ECM (15) changes the engine speed into the auto-idle speed. 4. When any one of the following condition exists, the auto-idle control is deactivated. •

•

Control lever: Operated [Pilot pressure sensors (2 to 9, 36 to 37): ON]

•

When power mode switch (31) is operated

• When engine control dial (32) is operated 5. MC (10) returns the signal sending to ECM (15) into the signal equivalent to the target engine speed set by engine control dial (32) immediately.

NOTE The auto-idle speed can be adjusted by MPDr. (11). (AI Speed) NOTE During aftertreatment device auto regeneration or the radiator coolant temperature auto-warming up control, the autoidle speed may not decrease down to a given level.

TOJBQ40-EN-00(07/02/2020)

T2-2-13

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 24

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

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T2-2-14

33343536373839404142-

TJAQ-02-02-011-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System Radiator Coolant Temperature Auto-Warming Up Control Purpose: The radiator coolant temperature auto-warming up control automatically warms up the engine.

TDC1-02-02-053-1 ja

A- Engine Speed B- Engine Control Dial Position C- Slow Idle Speed Position D- Fast Idle Speed Position

E- Fast Idle Speed F- Auto-Warming Up Speed G- Slow Idle Speed (min-1) 1330

750 0

(°C) TJAQ-02-02-012-1 ja

Operation: 1. ECM (15) receives the signal from coolant temperature sensor (16). 2. When key switch (33) is in the ON or START position, MC (10) receives the signal of coolant temperature sensor (16) from ECM (15). MC (10) sends the signal equivalent to the target engine speed according to the received signals to ECM (15) by using CAN communication (14). 3. ECM (15) increases the engine speed to the auto-warming up speed. 4. When the coolant temperature increases beyond the specified value, MC (10) deactivates the radiator coolant temperature auto-warming up control. 5. ECM (15) returns the engine speed to the engine speed set by engine control dial (32).

NOTE The slow idle speed can be adjusted by MPDr. (11). (Li Speed)

IMPORTANT When adjusting the slow idle speed, deactivate the auto warming-up control by using MPDr. (11). Or make an adjustment after the coolant temperature reaches 55°C.

TOJBQ40-EN-00(07/02/2020)

T2-2-15

SECTION2 SYSTEM Group2 Control System NOTE The auto warming-up control can be deactivated by MPDr. (11). (Radiator coolant temperature WU control selection) 29

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

TJAQ-02-02-013-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-16

SECTION2 SYSTEM Group2 Control System 123456789-

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

33343536373839404142-

Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

Engine Speed Slow Down Control Purpose: The engine speed slow down control gradually reduces the engine speed to the slow idle speed when the auto shutdown control is performed. Therefore, the loads of the engine and hydraulic actuator can be reduced.

TDC1-02-02-057-1 ja

A- Engine Speed B- Time

C- Slow Idle Speed

Operation: 1. MC (10) saves the engine speed at the moment when the auto shut-down control is performed. 2. MC (10) sends the signal that the engine speed gradually reduces from the saved engine speed to ECM (15) by using CAN communication (14). 3. ECM (15) changes the engine speed to the slow idle speed according to CAN communication (14). 4. Then, the auto shut-down control stops the engine. (Refer to "Auto Shut-Down Control"T2-2-80.)

TOJBQ40-EN-00(07/02/2020)

T2-2-17

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

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TOJBQ40-EN-00(07/02/2020)

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MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

T2-2-18

33343536373839404142-

TJAQ-02-02-014-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System One-Touch Idle Control (Option) Purpose: The one-touch idle control reduces the engine speed when the audio mute/one-touch idle switch is pushed. Therefore, the noise is reduced.

TDC1-02-02-047-1 ja

A- Engine Speed B- Engine Control Dial Position C- Slow Idle Speed Position

D- Fast Idle Speed Position E- Slow Idle Speed F- Fast Idle Speed

Operation: 1. When audio mute/one-touch idle switch (40) is pushed, monitor controller (12) sends the signal for audio mute/onetouch idle switch (40) in the ON position to MC (10) by using CAN communication (14). 2. MC (10) sends the signal of the target engine speed equivalent to the slow idle speed to ECM (15) by using CAN communication (14) regardless of the angle (required engine speed) of engine control dial (32). 3. ECM (15) changes the engine speed to the slow idle speed. 4. When any one of the following condition exists, the one-touch idle control is deactivated. •

Control lever: Operated [Pilot pressure sensors (2 to 9, 36 to 37): ON]

• When engine control dial (32) is operated 5. MC (10) returns the signal sending to ECM (15) into the signal equivalent to the target engine speed set by engine control dial (32) immediately.

NOTE Audio mute/one-touch idle switch (40) can be set to OFF, engine idle mode, radio mute mode, or engine idle/radio mute mode by MPDr. (11). (PBLI)

TOJBQ40-EN-00(07/02/2020)

T2-2-19

SECTION2 SYSTEM Group2 Control System 30

32 11

MODE

27 34

39 SW-BOX 13

41 38 37 36 9 8 7 6 5 4 3 2 1

40 14 35 DCU

10 MC

15 ECM

18 19 26

23 25 22

123456789-

TOJBQ40-EN-00(07/02/2020)

101112131415161718192021-

MC MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor

2223242526272829303132-

T2-2-20

33343536373839404142-

TJAQ-02-02-016-1 ja Key Switch Pilot Shut-Off Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Switch Box Controller Audio Mute/One-Touch Idle Switch 5-Spool Pilot Pressure Sensor Engine Oil Pressure Sensor

SECTION2 SYSTEM Group2 Control System Pump Control The pump control consists of the followings. ● Pump Flow Rate Control ● Engine Control Dial Output Control ● Speed Sensing Control ● Output Power Control ● ECO Mode Control ● Relief Flow Rate Decrease Control ● Swing High-Pressure Power Decrease Control ● Overheat Prevention Control ● Attachment Operation Pump Control (Option) ● Fan Pump Flow Rate Control (Air Conditioner Switch: OFF) ● Fan Pump Flow Rate Control (Air Conditioner Switch: ON) ● Pump and Valve Learning Control ● Pump Torque Restriction Control

TOJBQ40-EN-00(07/02/2020)

T2-2-21

SECTION2 SYSTEM Group2 Control System Pump Control System Layout 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-003-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-22

SECTION2 SYSTEM Group2 Control System 1234567891011-

Hydraulic Oil Temperature Sensor Boom Raise Pilot Pressure Sensor Arm Roll-In Pilot Pressure Sen sor Bucket Roll-In Pilot Pressure Sensor Swing Pilot Pressure Sensor Travel Pilot Pressure Sensor Attachment Pilot Pressure Sensor (Option) Front Pilot Pressure Sensor Boom Lower Pilot Pressure Sensor MC MPDr.

121314151617181920212223-

Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor Pump 1 Control Solenoid Valve Pump 2 Displacement Control Pressure Sensor

2425262728293031323334-

Pump 2 Control Solenoid Valve Pump 1 Displacement Control Pressure Sensor Fan Pump Control Solenoid Valve Arm 2 Flow Rate Control Sole noid Valve (SG) Swing Flow Rate Control Sole noid Valve (SI) Power Mode Switch Engine Control Dial Key Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor

353637383940414243-

44-

4-Spool Pilot Pressure Sensor Boom Mode Selector Control Solenoid Valve (SF) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC) Switch Box Controller 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) 5-Spool Pilot Pressure Sensor Main Relief Valve Control Sol enoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve (SC) Boost Temperature Sensor

Pump Flow Rate Control Purpose: The pump flow rate control supplies the required amount of oil to the actuators according to the control lever stroke. Operation: • When control lever is operated: 1. When the control lever moves, pressure oil from the pilot valve acts on individual pilot pressure sensors (2 to 9, 33 to 34) according to the lever stroke. 2. Individual pilot pressure sensors (2 to 9, 33 to 34) detect this pressure and sends the signals to MC (10). 3. MC (10) compares the pump displacement angle calculated from the pump 1 displacement control pressure sensor (25) and the pump 2 displacement control pressure sensor (23) with the signals from individual pilot pressure sensors (2 to 9, 33 to 34). 4. MC (10) calculates the required amount of oil and activates the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24). 5. The pump displacement angle increases and the pump delivery flow rate increases. • Control lever in neutral: 1. When the control lever is set to the neutral position, no pilot pressure oil is delivered to individual pilot pressure sensors (2 to 9, 33 to 34). 2. Individual pilot pressure sensors (2 to 9, 33 to 34) detect that no pressure is applied and send the signals to MC (10). 3. MC (10) compares the actual pump displacement angle detected by the pump 1 displacement control pressure sensor (25) and the pump 2 displacement control pressure sensor (23) with the signals from individual pilot pressure sensors (2 to 9, 33 to 34). 4. MC (10) calculates the required amount of oil and activates the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24). 5. The pump displacement angle reaches the minimum and the pump delivery flow rate is minimized.

NOTE When performing boom lower operation, the boom falls due to the own weight by the boom regenerative valve operation. Therefore, the pump delivery flow rate does not increase when performing boom lower operation. When jacking up, the pump delivery flow rate increases as the boom cylinder is operated by the pump delivery flow rate.

TOJBQ40-EN-00(07/02/2020)

T2-2-23

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-004-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-24

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Engine Control Dial Output Control Purpose: The engine control dial output control controls the P-Q curve according to the rotation angle of engine control dial (30). Therefore, the actuator speed changes smoothly according to the rotation angle of engine control dial (30). G

I A C

D TJAQ-02-02-034-1 ja

A- Target Engine Speed C- Slow Idle Speed Position D- Fast Idle Speed Position

G- Pump Driving Torque I- Minimum Pump Driving Torque J- Maximum Pump Driving Torque

Operation: 1. MC (10) receives the signals of the rotation angle of engine control dial (30). MC (10) controls the P-Q curve according to the received signals. 2. The pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) are restricted to the target displacement angle of pump1, pump 2 according to the P-Q curve. 3. Therefore, the engine control dial output control controls the P-Q curve.

TOJBQ40-EN-00(07/02/2020)

T2-2-25

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-005-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-26

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Speed Sensing Control Purpose: The speed sensing control controls the P-Q curve in response to the engine speed changes according to the variations in the load so that the engine output power can be utilized more efficiently. The engine stall is prevented when the machine is operated under the adverse conditions such as operating at the high altitude. Q

HP/PWR Mode TJAQ-02-02-018-1 ja Q

ECO Mode TJAQ-02-02-019-1 ja

P- Pressure TOJBQ40-EN-00(07/02/2020)

Q- Flow Rate

T2-2-27

SECTION2 SYSTEM Group2 Control System Operation: 1. The target engine speed is set by using engine control dial (30). 2. ECM (15) receives the signals from cam angle sensor (18) and crank speed sensor (19). 3. ECM (15) calculates them and sends the actual engine speed to MC (10) by using CAN communication (14). 4. MC (10) calculates the difference in the speed between the target engine speed and the actual engine speed that is received through CAN communication (14) from ECM (15). 5. MC (10) controls the P-Q curve in response to the difference in engine speed and sends the signals to the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24). 6. The pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) delivers pilot pressure to the regulators according to the signals so that the pump delivery flow rate is controlled. 7. If the load on engine (17) increases and the actual engine speed becomes slower than the target engine speed, the pump displacement angle is shifted to the minimum so that the delivery flow rate decreases. Therefore, the load of engine (17) is reduced and the engine stall is prevented. 8. If the load on engine (17) decreases and the actual engine speed becomes faster than the target engine speed, the pump displacement angle is shifted to the maximum so that the delivery flow rate increases. Therefore, the load on engine (17) increases so that the engine output power can be utilized more efficiently. (HP/PWR Mode)

TOJBQ40-EN-00(07/02/2020)

T2-2-28

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-006-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-29

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Output Power Control Purpose: In order for the sum of the P-Q curves assigned to pump 1, pump 2, and the fan pump not to exceed the engine output torque, The output power control controls the delivery flow rate of each pump. When the output of one pump is low, the P-Q curve of the other pump is raised so that the engine output power can be utilized more efficiently. Operation: 1. MC (10) limits the delivery flow rate of pump 1 and pump 2 so that the signals from the pump 1 delivery pressure sensor (20) and the pump 2 delivery pressure sensor (21) do not exceed the P-Q curve. 2. Therefore, the engine output torque is controlled so as not to be exceeded. 3. Under the condition where pump 1 and pump 2 are being operated, a pressure difference may occur in delivery pressure. 4. For a pump with high delivery pressure, its pump flow rate is limited at the P-Q curve, whereas for a pump with low delivery pressure, there is room before the P-Q curve. 5. The pump 1 delivery pressure sensor (20), the pump 2 delivery pressure sensor (21), the pump 1 displacement angle sensor (25), and the pump 2 displacement angle sensor (23) detect this state and sends the signals to MC (10). 6. MC (10) adds torque corresponding to room before the P-Q curve on the low delivery pressure side to the P-Q curve on the high delivery pressure side within the range where the engine output torque is not exceeded.

NOTE The delivery flow rate of the fan pump is controlled by the fan pump flow rate control regardless of the engine output torque. (Refer to "Radiator Fan Pump Flow Rate Control (Air Conditioner Switch: OFF)"T2-2-42.)

TOJBQ40-EN-00(07/02/2020)

T2-2-30

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-007-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-31

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

ECO/PWR Mode Control Purpose: The ECO/PWR mode control sets the P-Q curve to be lower than that in the HP mode to reduce the load on the engine so that fuel consumption is improved. In addition, the engine stall is prevented when the machine is operated under the adverse conditions such as operating at the high altitude. Q

P TJAQ-02-02-023-1 ja

P- Pressure

Q- Flow Rate

Operation: 1. When power mode switch (29) is in the ECO/PWR mode position, the signal is sent to MC (10). 2. MC (10) controls the P-Q curve according to the signals from the pump 1 delivery pressure sensor (20), the pump 2 delivery pressure sensor (21) and power mode switch (29).

TOJBQ40-EN-00(07/02/2020)

T2-2-32

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-008-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-33

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Relief Flow Rate Decrease Control Purpose: The relief flow rate decrease control reduces a loss of hydraulic energy and an increase in hydraulic oil temperature. Q Qm

A Qo Pc

P TJAQ-02-02-025-1 ja

P- Pressure A- Relief Cutoff

Q- Flow Rate B- Relief Cutoff Cut

Operation: 1. When the actuator is operated, the pressure signals input to the pump 1 delivery pressure sensor (20) and the pump 2 delivery pressure sensor (21) change depending on the load. 2. The pump 1 delivery pressure sensor (20) and the pump 2 delivery pressure sensor (21) detect delivery pressure and send the signals to MC (10). 3. When pump delivery pressure becomes the setting value, MC (10) compares it with the pump displacement angle calculated from the pump 1 displacement control pressure sensor (25) and the pump 2 displacement control pressure sensor (23). 4. MC (10) activates the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) so that the pump delivery flow rate decreases. 5. When performing travel or swing operation, the travel pilot pressure sensor (6) or the swing pilot pressure sensor (5) sends the signals to MC (10). 6. MC (10) cancels the relief flow rate decrease control of the pumps.

NOTE When power mode switch (29) is in the ECO/PWR mode position, the flow rate is minimized. In the HP mode, the flow rate is minimized only when oil temperature is low.

TOJBQ40-EN-00(07/02/2020)

T2-2-34

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-009-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-35

SECTION2 SYSTEM Group2 Control System 1-

234567891011-

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2425262728293031323334-

353637383940414243-

44-

Swing High Pressure Power Decrease Control Purpose: The swing high-pressure power decrease control reduces the delivery flow rate of pump 2 when performing swing single operation or combined operation of boom lower and swing, reducing energy consumption. Operation: 1. When all following conditions exist, MC (10) activates the pump 2 control solenoid valve (24). •

Swing pilot pressure: Large

•

Swing pilot pressure sensor (5): Outputting signal; or Boom lower pilot pressure sensor (9) and swing pilot pressure sensor (5): No signal

• Pump 2 Delivery Pressure: High-pressure 2. The pump 2 control solenoid valve (24) delivers pilot pressure to the regulator according to the signals so that the delivery flow rate of pump 2 decreases.

TOJBQ40-EN-00(07/02/2020)

T2-2-36

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-010-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-37

SECTION2 SYSTEM Group2 Control System 1-

234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Overheat Prevention Control Purpose: The overheat prevention control reduces the maximum flow rate of the pumps and lowers the P-Q curve when coolant temperature and hydraulic oil temperature increases to their specified values or higher. Therefore, the load on the engine is reduced so that the overheating is prevented. Q

P TJAQ-02-02-027-1 ja

P- Pressure

Q- Flow Rate

Operation: 1. ECM (15) sends the signals of coolant temperature sensor (16) to MC (10) by using CAN communication (14). 2. MC (10) reduces the maximum flow rate of the pumps and lowers the P-Q curve when coolant temperature becomes 99 °C or higher. 3. The signals from the hydraulic oil temperature sensor (1) are sent to MC (10). 4. MC (10) reduces the maximum flow rate of the pumps and lowers the P-Q curve when hydraulic oil temperature becomes 100 °C or higher. 5. When one of the following conditions exist, the overheat prevention control stops. •

Coolant temperature: 95 °C or less

•

Hydraulic oil temperature: 95 °C or less

TOJBQ40-EN-00(07/02/2020)

T2-2-38

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-011-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-39

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Attachment Operation Pump Control (Option) Purpose: The attachment operation pump control limits the upper limit of the maximum flow rate of pump 2 to control the installed attachment to be the appropriate flow rate when the attachment is operated. Operation: 1. When the breaker (attachment pilot valve) is operated, the attachment pilot pressure sensor (7) detects attachment pilot pressure and sends the signal to MC (10). 2. MC (10) always detects the calculated displacement angle from the pump 1 displacement control pressure sensor (25) and the pump 2 displacement control pressure sensor (23). 3. MC (10) activates the pump 2 control solenoid valve (24) and holds the displacement angle of pump 2 when the displacement angle of pump 2 reaches the displacement angle for the maximum flow rate specified in the attachment mode. 4. The attachment is controlled by the auxiliary spool on the 5-spool side of the control valve and only the maximum flow rate of pump 2 is controlled.

NOTE Returning oil from the breaker directly flows to the hydraulic oil tank without flowing through the oil cooler and hydraulic oil temperature increases. In order to prevent it, MC (10) activates the pump 1 control solenoid valve (22) to increase the delivery flow rate of pump 1 when the breaker is operated. Consequently, the amount of oil flowing to the oil cooler increases and restricts an increase in hydraulic oil temperature so that the overheating caused when the breaker is operated is prevented.

TOJBQ40-EN-00(07/02/2020)

T2-2-40

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-028-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-41

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

353637383940414243-

44-

Radiator Fan Pump Flow Rate Control (Air Conditioner Switch: OFF) Purpose: The radiator fan pump flow rate control controls the delivery flow rate of the fan pump according to boost temperature, coolant temperature, and hydraulic oil temperature. Operation: 1. ECM (15) sends the signals of boost temperature sensor (44) and coolant temperature sensor (16) to MC (10) by using CAN communication (14). 2. The hydraulic oil temperature sensor (1) sends the signals to MC (10). 3. MC (10) calculates the fan speed according to each received signal. 4. MC (10) sends the highest output signal of the calculated fan speeds to the fan pump control solenoid valve (26) to control the delivery flow rate of the fan pump. 5. Therefore, the fan speed is properly controlled.

TOJBQ40-EN-00(07/02/2020)

T2-2-42

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

14 18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-012-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-43

SECTION2 SYSTEM Group2 Control System 123456789101112-

131415161718192021222324-

Monitor CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor Pump 1 Control Solenoid Valve Pump 2 Displacement Control Pressure Sensor Pump 2 Control Solenoid Valve

2526272829303132333435-

Pump 1 Displacement Control Pressure Sensor Fan Pump Control Solenoid Valve Arm 2 Flow Rate Control Sole noid Valve (SG) Swing Flow Rate Control Sole noid Valve (SI) Power Mode Switch Engine Control Dial Key Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor

3637383940414243-

444546-

Boom Mode Selector Control Solenoid Valve (SF) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC) Switch Box Controller 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) 5-Spool Pilot Pressure Sensor Main Relief Valve Control Sol enoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve (SC) Boost Temperature Sensor Air Conditioner Controller Ambient Temperature Sensor

Radiator Fan Pump Flow Rate Control (Air Conditioner Switch: ON) Purpose: The fan pump flow rate control controls the delivery flow rate of the fan pump according to boost temperature, coolant temperature, hydraulic oil temperature, and ambient temperature. In addition, even when the engine speed is low with tje air conditioner ON, the delivery flow rate of the fan pump is controlled so as not to decrease. Therefore, the fan speed is controlled so that temperature of the oil cooler, radiator, intercooler, and air conditioner condenser becomes appropriate. Operation: 1. ECM(15) sends the signals of boost temperature sensor (44) and coolant temperature sensor (16) to MC (10) by using CAN communication (14). 2. Air conditioner controller (45) send the signals of ambient temperature sensor (46) to MC (10) by using CAN communication (14). 3. The signals of the hydraulic oil temperature sensor (1) are sent to MC (10). 4. Engine control dial (30) sends the signals of the target engine speed to MC (10). 5. MC(10) calculates the fan speed according to each received signal. 6. MC(10) sends the highest output signal of the calculated fan speeds to the fan pump control solenoid valve (26) to control the delivery flow rate the fan pump. 7. Therefore, the fan speed is properly controlled regardless of the engine control.

TOJBQ40-EN-00(07/02/2020)

T2-2-44

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

14 18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-013-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-45

SECTION2 SYSTEM Group2 Control System 1-

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2526272829303132333435-

3637383940414243-

444546-

Pump and Valve Learning Control Purpose: The pump and valve learning control corrects current and control pressure when the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) are activated, which are fundamental in the pump control. The pump and valve learning control also corrects current and control pressure when the 4-spool bypass shut-out control solenoid valve (SG) (39) and the 5-spool bypass shut-out control solenoid valve (SC) (37) are activated. Operation: 1. When all following conditions exist and the learning switch (48) in the rear console is tilted to the pump learning side (opposite to E), MC (10) activates the pump 1 control solenoid valve (22), the pump 2 control solenoid valve (24), the 4-spool bypass shut-out control solenoid valve (SG) (39), and the 5-spool bypass shut-out control solenoid valve (37). •

Engine (17): Started

•

Each pilot pressure sensor: No signal (Control lever in neutral)

•

Hydraulic oil temperature: 50 ± 5 °C

• Pilot shut-off switch (44): ON (Pilot shut-off lever: LOCK Position) 2. The pump 1 control solenoid valve (22), the pump 2 control solenoid valve (24), the 4-spool bypass shut-out control solenoid valve (SG) (39), and the 5-spool bypass shut-out control solenoid valve (SC) (37) are activated. 3. The signals from the pump 1 displacement control pressure sensor (25) and the pump 2 displacement control pressure sensor (23) when the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) are activated are sent to MC (10). The signals from the pump 1 delivery pressure sensor (20) and the pump 2 delivery pressure sensor (21) when the 4-spool bypass shut-out control solenoid valve (SG) (39) and the 5-spool bypass shutout control solenoid valve (SC) (37) are activated are sent to MC (10). 4. MC (10) corrects current when the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) are activated and control pressure at that time. MC (10) also corrects current when the 4-spool bypass shut-out control solenoid valve (SG) (39) and the 5-spool bypass shut-out control solenoid valve (SC) (37) are activated and control pressure at that time.

IMPORTANT When the following components are replaced, perform the pump, valve learning control. [Refer to T/M (Troubleshooting)] •

Replacement of the pumps, the pump regulators, the pump 1 control solenoid valve (22), the pump 2 control solenoid valve (24), the control valve, the 4-spool bypass shut-out control solenoid valve (SG) (39), and the 5spool bypass shut-out control solenoid valve (SC) (37)

•

Replacement of MC (10)

TOJBQ40-EN-00(07/02/2020)

T2-2-46

SECTION2 SYSTEM Group2 Control System NOTE Pump learning is not necessary when the battery is replaced. 49

30 11

MODE

44 38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 45

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-014-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-47

SECTION2 SYSTEM Group2 Control System 12345678910111213-

141516171819202122232425-

CAN ECM Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor Pump 1 Control Solenoid Valve Pump 2 Displacement Control Pressure Sensor Pump 2 Control Solenoid Valve Pump 1 Displacement Control Pressure Sensor

262728293031323334353637-

Fan Pump Control Solenoid Valve Arm 2 Flow Rate Control Sole noid Valve (SG) Swing Flow Rate Control Sole noid Valve (SI) Power Mode Switch Engine Control Dial Key Switch DCU Arm Roll-Out Pilot Pressure Sensor Bucket Roll-Out Pilot Pressure Sensor 4-Spool Pilot Pressure Sensor Boom Mode Selector Control Solenoid Valve (SF) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC)

383940414243-

444546474849-

Switch Box Controller 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) 5-Spool Pilot Pressure Sensor Main Relief Valve Control Sol enoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve (SC) Pilot Shut-Off Switch Boost Temperature Sensor Air Conditioner Controller Ambient Temperature Sensor Learning Switch Auto-Idle Switch

Pump Torque Restriction Control Purpose: The pump torque restriction control reduces the delivery flow rate to decrease the pump driving torque according to the step of engine output restriction during engine output restriction. Operation: 1. MC (10) activates the pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) when a specified time has passed after an abnormality occurs in the urea SCR system or the EGR system. 2. The pump 1 control solenoid valve (22) and the pump 2 control solenoid valve (24) deliver pilot pressure to the regulators according to the signals so that the pump delivery flow rate decreases.

TOJBQ40-EN-00(07/02/2020)

T2-2-48

SECTION2 SYSTEM Group2 Control System 29

30 11

MODE

38 SW-BOX 13

31 12 41 35 34 33 9 8 7 6 5 4 3 2 1

14 32 DCU

10 MC

15 ECM

18 19

23 44

25 22

27 28 36 37 39 40 42 43 TJBQ-02-02-015-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-49

SECTION2 SYSTEM Group2 Control System 1234567891011-

121314151617181920212223-

2425262728293031323334-

Valve Control (Standard) The valve control consists of the followings. ● Pressure Increase Selection Control When Traveling ● Power Digging Control ● Auto-Power Lift Control ● Travel Motor Displacement Angle Control ● Boom Mode Selector Control ● Swing Flow Rate Control ● Arm 2 Flow Rate Control ● Bucket Flow Combiner Control ● Aftertreatment Device Manual Regeneration Control ● Aftertreatment Device Auto Regeneration Control ● Engine Protection Control at Low Temperature ● Oil Cooler Fan Rotation Control ● Radiator, Oil Cooler Fan Reverse Rotation Control ● Arm Regenerative Cut Control

TOJBQ40-EN-00(07/02/2020)

T2-2-50

353637383940414243-

44-

SECTION2 SYSTEM Group2 Control System Valve Control (Standard) System Layout 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-016-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-51

SECTION2 SYSTEM Group2 Control System 123456789101112131415-

16171819202122232425262728293031-

ECM Manual Regeneration Switch Coolant Temperature Sensor Engine Cam Angle Sensor Crank Speed Sensor 5-Spool Pilot Pressure Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor 4-Spool Pilot Pressure Sensor Fan Pump Control Solenoid Valve Pump 2 Displacement Control Pressure Sensor Pump 1 Displacement Control Pressure Sensor Boost Temperature Sensor Main Relief Valve Pump 1 Control Solenoid Valve

3233343536373839404142434445464748-

Control Valve Arm 2 Flow Rate Control Valve Pump 1 Bypass Shut-Out Valve Pump 2 Control Solenoid Valve Swing Flow Rate Control Valve Travel Motor Displacement Angle Control Valve Arm Regenerative Cut Valve Arm 2 Flow Rate Control Sole noid Valve (SG) Power Boost Switch Travel Mode Switch Slow Speed Position Fast Speed Position Power Mode Switch Engine Control Dial Key Switch Pilot Shut-Off Switch DCU

49505152535455565758-

5960-

Bucket Roll-Out Pilot Pressure Sensor Pump 2 Bypass Shut-Out Valve Swing Flow Rate Control Sole noid Valve Boom Mode Selector Control Solenoid Valve (SF) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC) Switch Box Controller 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) Main Relief Valve Control Sol enoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve (SC) Boom Mode Selector Switch Boom Overload Relief Valve

Pressure Rising Selection Control When Traveling Purpose: The pressure increase selection control when traveling increases pressure in the main relief valve during travel operation. Operation: 1. When the following conditions exist, MC (11) activates the main relief valve control solenoid valve (SF) (57). • Travel pilot pressure sensor (6): Outputting signal 2. When the main relief valve control solenoid valve (SF) (57) is activated, pilot pressure acts on main relief valve (30) to increase relief pressure. (Refer to COMPONENT OPERATION/Control Valve.)

TOJBQ40-EN-00(07/02/2020)

T2-2-52

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-017-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-53

SECTION2 SYSTEM Group2 Control System 123456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Power Digging Control Purpose: The power digging control increases the digging force by temporarily increasing the relief pressure. Operation: 1. For maximum eight seconds after power boost switch (40) is turned ON, MC (11) continuously activates the main relief valve control solenoid valve (SF) (57). 2. When the main relief valve control solenoid valve (SF) (57) is activated, pilot pressure acts on main relief valve (30) to increase relief pressure. (Refer to COMPONENT OPERATION/Control Valve.)

TOJBQ40-EN-00(07/02/2020)

T2-2-54

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-018-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-55

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Auto-Power Lift Control Purpose: The auto-power lift control increases the relief pressure when raising the boom. Operation: 1. When all following conditions exist, MC (11) activates the main relief valve control solenoid valve (SF) (57). •

Boom raise pilot pressure sensor (2): Outputting signal

•

Pump 1 delivery pressure sensor (23): High (Reference: 29 MPa or more)

• Arm roll-in pilot pressure sensor (3): No signal 2. When the main relief valve control solenoid valve (SF) (57) is activated, pilot pressure acts on main relief valve (30) to increase relief pressure. (Refer to COMPONENT OPERATION/Control Valve.)

NOTE The auto-power lift control is performed when performing combined operation except arm roll-in as well as single operation.

TOJBQ40-EN-00(07/02/2020)

T2-2-56

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-019-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-57

SECTION2 SYSTEM Group2 Control System 123456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Travel Motor Displacement Angle Control Purpose: The travel motor displacement angle control controls the travel mode. Operation: •

Slow 1. When travel mode switch (41) is in slow speed position (42), the travel motor displacement angle is kept in the maximum angle so that the travel speed is slow.

•

Fast 1. When all following conditions exit, MC (11) shifts the travel motor displacement angle control solenoid valve (SC) (58). •

Travel mode switch (41): Fast speed (43)

•

Travel pilot pressure sensor (6): Outputting signal

•

Pump 1 delivery pressure sensor (23), pump 2 delivery pressure sensor (24): Both pump delivery pressures are low (Reference: 27.6 MPa or less)

Pilot pressure of either the 4-spool pilot pressure sensor (25) or the 5-spool pilot pressure sensor (22) is high. (Reference: 2.0 MPa or more) 2. When the travel motor displacement angle control solenoid valve (SC) (58) is shifted, pilot pressure acts on the travel motor displacement angle control valve (37). The displacement angle of the travel motor is shifted to the minimum and the travel speed increases. •

NOTE When the track link on one side is jacked up and is rotated, pilot pressure of either the 4-spool pilot pressure sensor (25) or the 5-spool pilot pressure sensor (22) increases so that the track link rotates at fast speed.

TOJBQ40-EN-00(07/02/2020)

T2-2-58

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-020-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-59

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Boom Mode Selector Control Purpose: The boom mode selector control decreases relief set pressure in the boom cylinder rod side overload relief valve so that vibration of the machine is reduced. Operation: 1. The signals from individual pilot pressure sensors (2 to 10, 49) are sent to MC (11). 2. When the following conditions exist, MC (11) activates the boom mode selector control solenoid valve (SF) (52). •

Boom Mode Selector Switch (59): ON

•

Travel pilot pressure sensor (6): No signal

• Individual pilot pressure sensors (2 to 5, 7 to 10, 49): Signal output from one of them 3. Pressure oil from the pilot pump flows through the boom mode selector control solenoid valve (SF) (52) and acts on the boom overload relief valve (60). 4. When the boom overload relief valve (60) is shifted, relief set pressure in the overload relief valve decreases. 5. Holding pressure on the boom cylinder rod side decreases and vibration of the machine is reduced when performing boom lower operation. (Refer to COMPONENT OPERATION/Control Valve, Boom Overload Relief Valve.)

NOTE When the output from one of the pilot pressure sensors (2 to 10, 49) reaches 0.7 MPa or more, MC (11) recognizes that the control lever is being operated.

TOJBQ40-EN-00(07/02/2020)

T2-2-60

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-021-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-61

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Swing Flow Rate Control Purpose: The swing flow rate control restricts pressure oil flowing to the swing to delivers more pressure oil to the boom or the arm when performing combined operation of swing and boom raise or of swing and arm roll-out so that the operating speed of the boom or the arm is maintained. Operation: 1. When any following conditions exist, MC (11) activates the swing flow rate control solenoid valve (SI) (51). •

Combined operation of swing and boom raise

• Combined operation of swing and arm roll-out 2. When the swing flow rate control solenoid valve (SI) (51) is activated, pilot pressure shifts the swing flow rate control valve (36). 3. Pressure oil which flows to the swing spool from pump 2 is restricted by swing flow rate control valve (36). 4. Pressure oil from pump 2 flows to the spools except swing and the operating speed of the boom or the arm is maintained.

TOJBQ40-EN-00(07/02/2020)

T2-2-62

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-022-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-63

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Arm 2 Flow Rate Control Purpose: The arm 2 flow rate control increases pressure oil flowing to arm 2 and delivers more pressure oil to the arm so that the operating speed of the arm is maintained when performing arm roll-in or arm roll-out single operation. Operation: 1. When any following conditions exist, MC (11) activates the arm 2 flow rate control solenoid valve (SG) (39). •

Arm roll-in pilot pressure sensor (3): Outputting signal

•

Arm roll-out pilot pressure sensor (10): Outputting signal

•

Boom raise pilot pressure sensor (2): No signal

• Pump 2 Delivery Pressure: High 2. When the arm 2 rate control solenoid valve (SG) (39) is activated, pilot pressure shifts the arm 2 flow rate control valve (33). 3. The pressure oil flow rate from pump 1 to the arm 2 spool increases. 4. Consequently, the operating speed of the arm is maintained.

TOJBQ40-EN-00(07/02/2020)

T2-2-64

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-023-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-65

SECTION2 SYSTEM Group2 Control System 123456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Bucket Flow Combiner Control Purpose: The bucket flow combiner control combines pressure oil from pump 1 with pressure oil from pump 2 at the bucket spool when performing bucket single operation so that the bucket operating speed increases. Operation: 1. When the following conditions exist, MC (11) activates the 5-spool bypass shut-out control solenoid valve (SC) (53). • Bucket roll-in pilot pressure sensor (4) or Bucket roll-out pilot pressure sensor (49): Outputting signal 2. When the 5-spool bypass shut-out control solenoid valve (SC) (53) is activated, pilot pressure shifts the pump 2 bypass shut-out valve (50). 3. The neutral circuit of pump 2 is blocked and pressure oil from pump 2 is combined with pressure oil from pump 1. 4. Therefore, the bucket operating speed increases.

TOJBQ40-EN-00(07/02/2020)

T2-2-66

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-024-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-67

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Aftertreatment Device Manual Regeneration Control Purpose: The aftertreatment device manual regeneration control regenerates the aftertreatment device manually when all following conditions exist. •

Aftertreatment device manual regeneration request is displayed on monitor (15)

• Manual regeneration switch (17): ON position As this control increases the pump load during regeneration, the load is applied to the engine. Therefore, this control assists to increase the exhaust temperature up to the temperature that a catalyst in the aftertreatment device is activated. Operation: 1. MC (11) receives the aftertreatment device regeneration signal from ECM (16) by using CAN communication (12). 2. When all following conditions exist, MC (11) activates the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53). At the same time, MC (11) activates the pump 1 control solenoid valve (31) and the pump 2 control solenoid valve (35). •

Engine control dial (45): Slow idle speed position

•

Pilot shut-off switch (47): ON position (Pilot shut-off lever: LOCK Position)

• Manual regeneration switch (17): ON position 3. When the pump 1 control solenoid valve (31) and the pump 2 control solenoid valve (35) are activated, the delivery flow rate of pump 1 and pump 2 increases. 4. When the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53) are activated, the pump 1 bypass shut-out valve (34) and the pump 2 bypass shut-out valve (50) are shifted by pilot pressure. 5. When the pump 1 bypass shut-out valve (34) and the pump 2 bypass shut-out valve (50) are shifted, the neutral circuit of pump 1 and pump 2 is partially blocked and the neutral circuit pressure of pump 1 and pump 2 increases. 6. MC (11) receives the pressure signals of the neutral circuit of pump 1 and pump 2 from the pump 1 delivery pressure sensor (23) and the pump 2 delivery pressure sensor (24). 7. In order to set the neutral circuit pressure of pump 1 and pump 2 to the target delivery pressure (10 MPa), MC (11) activates the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53) according to the signals from the pump 1 delivery pressure sensor (23) and the pump 2 delivery pressure sensor (24). 8. Therefore, the exhaust temperature increases by increasing the load to the engine.

TOJBQ40-EN-00(07/02/2020)

T2-2-68

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-025-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-69

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

495051525354555657585960-

Bucket Roll-Out Pilot Pressure Sensor Pump 2 Bypass Shut-Out Valve Swing Flow Rate Control Sole noid Valve Boom Mode Selector Control Solenoid Valve (SF) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC) Switch Box Controller 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) Main Relief Valve Control Sol enoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve Boom Mode Selector Switch Boom Overload Relief Valve

Aftertreatment Device Auto Regeneration Control Purpose: The aftertreatment device auto regeneration control regenerates the aftertreatment device automatically. As this control increases the pump load during regeneration, the load is applied to the engine. Therefore, this control assists to increase the exhaust temperature up to the temperature that a catalyst in the aftertreatment device is activated. Operation: 1. MC (11) receives the aftertreatment device regeneration signal from ECM (16) by using CAN communication (12). 2. When all following conditions exist, MC (11) activates the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53). At the same time, MC (11) activates the pump 1 control solenoid valve (31) and the pump 2 control solenoid valve (35). •

15 hours passed after the completion of the previous regeneration

•

The output signal from the differential pressure sensor at a certain pressure level or more before 15 hours pass after the completion of the previous regeneration

Control lever: All control levers are held in the neutral position [Each pilot pressure sensor (2 to 10, 49): OFF] for 3.0 seconds or more 3. When the pump 1 control solenoid valve (31) and the pump 2 control solenoid valve (35) are activated, the delivery flow rate of pump 1 and pump 2 increases. 4. When the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53) are activated, the pump 1 bypass shut-out valve (34) and the pump 2 bypass shut-out valve (50) are shifted by pilot pressure. 5. When the pump 1 bypass shut-out valve (34) and the pump 2 bypass shut-out valve (50) are shifted, the neutral circuit of pump 1 and pump 2 is partially blocked and the neutral circuit pressure of pump 1 and pump 2 increases. 6. MC (11) receives the pressure signals of the neutral circuit of pump 1 and pump 2 from the pump 1 delivery pressure sensor (23) and the pump 2 delivery pressure sensor (24). 7. In order to set the neutral circuit pressure of pump 1 and pump 2 to the target delivery pressure (10 MPa), MC (11) activates the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53) according to the signals from the pump 1 delivery pressure sensor (23) and the pump 2 delivery pressure sensor (24). 8. Therefore, the exhaust temperature increases by increasing the load to the engine. •

TOJBQ40-EN-00(07/02/2020)

T2-2-70

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-026-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-71

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Engine Protection Control at Low Temperature Purpose: When the machine is left with the engine running for a long time at a low temperature of -5 °C or less, ice or frost forms in the line that returns from the blow-by hose to the intake side, which may damage the engine. To prevent damage to the engine when the machine is left with the engine running for a long time, the engine protection control at low temperature applies a load to the engine, which increases the exhaust temperature and melts the ice or frost that has formed. Operation: 1. When all following conditions exist, MC (11) activates the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53). At the same time, MC (11) activates the pump 1 control solenoid valve (31) and the pump 2 control solenoid valve (35). •

Pilot shut-off switch (47): ON (60 minutes) (Pilot shut-off lever: LOCK Position)

• Ambient temperature or intake-air temperature: -5 ℃ or less 2. When the pump 1 control solenoid valve (31) and the pump 2 control solenoid valve (35) are activated, the delivery flow rate of pump 1 and pump 2 increases. 3. When the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53) are activated, the pump 1 bypass shut-out valve (34) and the pump 2 bypass shut-out valve (50) are shifted by pilot pressure. 4. When the pump 1 bypass shut-out valve (34) and the pump 2 bypass shut-out valve (50) are shifted, the neutral circuit of pump 1 and pump 2 is partially blocked and the neutral circuit pressure of pump 1 and pump 2 increases. 5. MC (11) receives the pressure signals of the neutral circuit of pump 1 and pump 2 from the pump 1 delivery pressure sensor (23) and the pump 2 delivery pressure sensor (24). 6. In order to set the neutral circuit pressure of pump 1 and pump 2 to the target delivery pressure (10 MPa), MC (11) activates the 4-spool bypass shut-out control solenoid valve (SG) (55) and the 5-spool bypass shut-out control solenoid valve (SC) (53) according to the signals from the pump 1 delivery pressure sensor (23) and the pump 2 delivery pressure sensor (24). 7. Therefore, the exhaust temperature increases by increasing the load to the engine.

TOJBQ40-EN-00(07/02/2020)

T2-2-72

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-029-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-73

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Oil Cooler Fan Rotation Control Purpose: The oil cooler fan speed control controls the oil cooler fan speed to be the optimum fan speed according to the operating status of the air conditioner, ambient temperature, target engine speed, and hydraulic oil temperature so that the air conditioner condenser and the oil cooler are cooled. Operation: 1. Air conditioner (66) sends the air conditioner ON/OFF signal, blower level signal, and ambient temperature to MC (11) by using CAN communication (12). 2. When all following conditions exist, MC (11) activates the fan speed control solenoid valve (66) and controls the fan speed to be the optimum fan speed. •

The air conditioner switch is in the OFF position or the blower level display indicates 0 with hydraulic oil temperature of 55 °C or more. Or the engine speed is 750 min-1 or more.

•

The air conditioner switch is in the ON position, the blower level display indicates 1 or more, ambient temperature is 20 °C or more, and hydraulic oil temperature is 55 °C or more.

TOJBQ40-EN-00(07/02/2020)

T2-2-74

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

65 64 63

12 15

59 47

BM/M

54 SW-BOX

16 ECM

40 62 49 25 22 10 9 8 7 6 5 4 3 2 1

48 17 DCU

19 11 MC

18 29 20 21

28 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-002-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-75

SECTION2 SYSTEM Group2 Control System 123456789101112131415161718-

Hydraulic Oil Temperature Sensor Boom Raise Pilot Pressure Sensor Arm Roll-In Pilot Pressure Sensor Bucket Roll-In Pilot Pressure Sensor Swing Pilot Pressure Sensor Travel Pilot Pressure Sensor Attachment Pilot Pressure Sensor (Option) Front Pilot Pressure Sensor Boom Lower Pilot Pressure Sensor Arm Roll-Out Pilot Pressure Sensor MC CAN MPDr. Monitor Controller Monitor ECM Manual Regeneration Switch Coolant Temperature Sensor

19202122232425262728293031323334-

Engine Cam Angle Sensor Crank Speed Sensor 5-Spool Pilot Pressure Sensor Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor 4-Spool Pilot Pressure Sensor Fan Pump Control Solenoid Valve Pump 2 Displacement Con trol Pressure Sensor Pump 1 Displacement Con trol Pressure Sensor Boost Temperature Sensor Main Relief Valve Pump 1 Control Solenoid Valve Control Valve Arm 2 Flow Rate Control Valve Pump 1 Bypass Shut-Out Valve

353637383940414243444546474849505152-

Pump 2 Control Solenoid Valve Swing Flow Rate Control Valve Travel Motor Displacement Angle Control Valve Arm Regenerative Cut Valve Arm 2 Flow Rate Control Sol enoid Valve (SG) Power Digging Switch Travel Mode Switch Slow Speed Position Fast Speed Position Power Mode Switch Engine Control Dial Key Switch Pilot Shut-Off Switch DCU Bucket Roll-Out Pilot Pres sure Sensor Pump 2 Bypass Shut-Out Valve| Swing Flow Rate Control Sol enoid Valve Boom Mode Selector Control Solenoid Valve (SF)

535455565758-

596061626364656667-

5-Spool Bypass Shut-Out Control Solenoid Valve (SC) witch Box Controller 4-Spool Bypass Shut-Out Control Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) Main Relief Valve Control Solenoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve (SC) Boom Mode Selector Switch Boom Overload Relief Valve Fan Speed Control Solenoid Valve Fan Reverse Rotation Switch Fan Reverse Rotation Control Solenoid Valve 2 Oil Cooler Fan Reverse Rota tion Spool Oil Cooler Fan Valve Air Conditioner Ambient Temperature Sen sor

Radiator Fan and Oil Cooler Fan Reverse Rotation Control Purpose: The radiator, oil cooler fan reverse rotation control rotates the fan in the reverse direction for cleaning of the radiator and the oil cooler. Operation: 1. When the fan reverse rotation switch (62) is turned ON, MC (11) activates the fan reverse rotation control solenoid valve 1 (68) and the fan reverse rotation control solenoid valve 2 (63). 2. When the fan reverse rotation control solenoid valve 1 (68) and the fan reverse rotation control solenoid valve 2 (63) are activated, pressure oil from the oil cooler fan pump and the pilot pump shifts the radiator fan reverse rotation spool (71) and the oil cooler fan reverse rotation spool (64). 3. Radiator fan valve (72) and the oil cooler fan valve (65) are shifted and radiator fan motor (69) and oil cooler fan motor (70) rotates in the reverse direction. (Refer to SYSTEM/Hydraulic System.) 4. Therefore, dirt in the cores of the radiator and the oil cooler are discharged.

TOJBQ40-EN-00(07/02/2020)

T2-2-76

SECTION2 SYSTEM Group2 Control System

62 11 MC

69 70 65 68

67 64

116263-

MC Fan Reverse Rotation Switch Fan Reverse Rotation Control Solenoid Valve 2

6465-

Oil Cooler Fan Reverse Rota tion Spool Oil Cooler Fan Valve

686970-

Fan Reverse Rotation Control Solenoid Valve 1 Radiator Fan Motor Oil Cooler Fan Motor

7172-

TJBQ-02-02-001-1 ja Radiator Fan Reverse Rota tion Spool Rradiator Fan Valve

Arm Regenerative Cut Control Purpose: The arm regenerative cut control shifts the arm regenerative cut valve (38) according to other operating conditions and pump delivery pressure when performing arm roll-in operation. Therefore, pressure at the arm cylinder rod side decreases and improves the arm digging force. Operation: 1. When the following input conditions exist, MC (11) activates the arm regenerative control solenoid valve (SI) (56). •

Pump 1 delivery pressure sensor (23)

•

Pump 2 delivery pressure sensor (24)

•

Boom raise pilot pressure sensor (2)

•

Arm roll-in pilot pressure sensor (3)

• Swing pilot pressure sensor (5) 2. Pressure oil from the pilot pump flows through the arm regenerative control solenoid valve (SI) (56) and shifts the arm regenerative cut valve (38). TOJBQ40-EN-00(07/02/2020)

T2-2-77

SECTION2 SYSTEM Group2 Control System 3. Pressure oil from the arm cylinder rod side flows to the hydraulic oil tank. 4. The pressure at the arm cylinder rod side decreases and improves the digging force (arm). Also, the oil passage pressure loss is reduced in order to reduce fuel consumption.

TOJBQ40-EN-00(07/02/2020)

T2-2-78

SECTION2 SYSTEM Group2 Control System 43

45 13

MODE

12 15

59 47

BM/M

54 SW-BOX

48 DCU 23

16 ECM

40 49 25 22 10 9 8 7 6 5 4 3 2 1

19 11 MC

18 29 20 21

27 31

39 51 52 50

56 55 53

57 58

33 TJBQ-02-02-027-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-79

SECTION2 SYSTEM Group2 Control System 1-

23456789101112131415-

16171819202122232425262728293031-

3233343536373839404142434445464748-

49505152535455565758-

5960-

Other Control The other control consists of the followings. ● Work Mode Control ● Auto Shut-Down Control ● Hydraulic Oil Overheat Alarm Control ● Engine Oil, Coolant Level Check Control ● Auto-Lubrication Control (Option) ● Breaker Alarm Control (Option) ● Travel Alarm Control (Option) ● Overload Alarm Control (Option)

Auto Shut-Down Control Purpose: The auto shut-down control automatically stops the engine in order to reduce the fuel consumption when the operation is not performed in a specified time. Operation: 1. When all following conditions exist, MC (2) sends the auto shut-down signal to monitor controller (5) by using CAN communication (3). •

Pilot shut-off switch (15): ON position (Pilot shut-off lever: LOCK Position)

•

Auto shut-down: ON

•

Overheat alarm: OFF

•

Coolant temperature: 60 to 100 °C

•

Manual regeneration switch (9): OFF position

•

Abnormal communication of ECM (8) or monitor controller (5): None

•

Overload alarm switch (16): OFF position

•

Fan reverse rotation switch (17): OFF position

•

Learning switch (18): OFF position

TOJBQ40-EN-00(07/02/2020)

T2-2-80

SECTION2 SYSTEM Group2 Control System 2. Monitor controller (5) displays the auto shut-down notice on monitor (6) and sounds buzzer (7) once before 30 seconds for the auto shut-down enable time set by monitor (6). Monitor controller (5) sounds buzzer (7) continuously before 15 seconds. (intermittent sound) 3. MC (2) decreases the engine speed to the slow idle speed after the auto shut-down enable time is over. (Refer to "Engine Speed Slow Down Control"T2-2-17.) 4. When the engine speed is decreased to the slow idle speed, MC (2) turns OFF battery relay (13). Therefore, the engine stops. (Refer to SYSTEM / Electrical System.)

NOTE The auto shut-down ON/OFF can be selected and the time when the auto shut-down control is activated can be set by monitor (6). NOTE Return the key switch to the OFF or ACC position and reset it to the START position, and the engine can restart. 4 14

1 SW-BOX

6 5

7 3

2 MC

17 18 9 8 ECM

12 10

TJAQ-02-02-055-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-2-81

SECTION2 SYSTEM Group2 Control System 12345-

Switch Box Controller MC CAN MPDr. Monitor Controller

678910-

Monitor Buzzer ECM Manual Regeneration Switch Coolant Temperature Sensor

11121314-

Engine Pump 1 Delivery Pressure Sensor Battery Relay Engine Control Dial

15161718-

Pilot Shut-Off Switch Overload Alarm Switch Fan Reverse Rotation Switch Learning Switch

Hydraulic Oil Overheat Alarm Control Purpose: The hydraulic oil overheat alarm control sounds buzzer (7) when the hydraulic oil temperature exceeds the specified value. Operation: 1. MC (2) receives the signal from hydraulic oil temperature sensor (1). 2. When the oil temperature is kept high for a specified time, MC (2) sends the signal to monitor controller (5) by using CAN communication (3). 3. Monitor controller (5) sounds buzzer (7) and also displays the hydraulic oil overheat alarm on monitor (6). 4. When the oil temperature decreases, monitor controller (5) stops buzzer (7) and turns off the hydraulic oil overheat alarm on monitor (6).

NOTE The temperature, evaluation time, buzzer, and warning icon of the hydraulic oil overheat control can be made operable or inoperable by MPDr. (4). 1 4

3 6 2

7 TDAA-02-02-010-1 ja 1-

Hydraulic Oil Temperature Sensor

23-

MC CAN

45-

MPDr. Monitor Controller

67-

Monitor Buzzer

Engine Oil, Coolant Level Check Control Purpose: The engine oil, coolant level check control checks the coolant level and the engine oil level and displays the result on monitor (7). Operation: 1. When home switch (4) is held down with key switch (3) in the ON position, monitor controller (6) receives the signals.

TOJBQ40-EN-00(07/02/2020)

T2-2-82

SECTION2 SYSTEM Group2 Control System 4

őŖŔŉ

˩ˡ˪˱ Ŕņŕ

TDFY-05-02-001-2 ja

2. The signals from the engine oil level switch (1) and coolant level switch (2) are sent to monitor controller (6). 3. Monitor controller (6) displays the coolant level and the engine oil level on monitor (7). 3 4

1 2

HOME

8 SW-BOX

12-

Engine Oil Level Switch Coolant Level Switch

34-

Key Switch Home Switch

56-

MPDr. Monitor Controller

78-

TJAQ-02-02-058-1 ja Monitor Switch Box Controller

Auto-Lubrication Control (Option) Purpose: The auto-lubrication control controls the auto-lubrication device so that auto-lubrication is properly performed. (Refer to COMPONENT OPERATION / Others (Upperstructure), Distribution Valve) Operation: 1. When auto-lubrication switch (1) is set to the ON position, MC (2) connects terminal #F31 to the ground inside. 2. Therefore, auto-lubrication relay (8) is excited. 3. Current from fuse #30 (7) flows to grease pump (9) and proximity switch (11). 4. Grease pump (9) operates and auto-lubrication starts. 5. While auto-lubrication relay (8) is ON, grease pump (9) operates and discharges grease. 6. Upon discharge of grease from grease pump (9), the piston of distribution valve (10) starts stroke motion. 7. Proximity switch (11) is provided in distribution valve (10) and turned ON/OFF according to the piston stroke in distribution valve (10). 8. When the piston of distribution valve (10) gets close to proximity switch (11), proximity switch (11) is turned ON and transistor (12) in proximity switch (11) is turned ON. 9. Terminal #B24 in MC (2) connects to the ground through proximity switch (11). 10. When the piston of distribution valve (10) gets away from proximity switch (11), proximity switch (11) is turned OFF and transistor (12) in proximity switch (11) is turned OFF. 11. Terminal #B24 in MC (2) receives the signals from terminal #2 of proximity switch (11). 12. MC (2) detects the number of movements (strokes) of distribution valve (10) by the signals that terminal #B24 receives. 13. When the set number of movements (strokes) is reached, MC (2) disconnects terminal #F31 from the ground.

TOJBQ40-EN-00(07/02/2020)

T2-2-83

SECTION2 SYSTEM Group2 Control System 14. Therefore, auto-lubrication relay (8) is turned OFF and grease pump (9) stops as current stops flowing to grease pump (9). 15. After the set interval passed, MC (2) connects terminal #F31 to the ground again. Therefore, grease pump (9) activates and auto-lubrication resumes. 16. If no signal is sent from proximity switch (11) to terminal #B24 of MC (2) in 7.5 minutes after auto-lubrication relay (8) is turned ON, MC (2) recognizes that the auto-lubrication circuit is faulty (shortage of grease, faulty grease pump) and sends the signal to monitor controller (5) by using CAN communication (3). 17. Monitor controller (5) displays an auto-lubrication alarm on monitor (6).

NOTE The lubrication time and interval can be set on monitor (6) or by using MPDr. (4). 4

6 7

1 3

2 MC

5 8

F31 B24

2 1 11

12 1234-

Auto-Lubrication Switch MC CAN MPDr.

TOJBQ40-EN-00(07/02/2020)

5678-

Monitor Controller Monitor Fuse #30 Auto-Lubrication Relay

9101112-

T2-2-84

Grease Pump Distribution Valve Proximity Switch Transistor

13-

TJAQ-02-02-057-1 ja Current from Battery

SECTION2 SYSTEM Group2 Control System Breaker Alarm Control (Option) Purpose: The breaker alarm control sounds buzzer (3) when the breaker is used in a specified time continuously. Operation: 1. When the following conditions exist in a specified time continuously, MC (2) sends the signal to monitor controller (5). •

Work mode: Breaker 1 to 5

• Attachment Pilot Pressure Sensor (1) (Option): Outputting signal 2. Monitor controller (5) sounds buzzer (3).

NOTE The breaker alarm control can be made operable or inoperable by MPDr. (4) or monitor (6). 1 4

6 2 MC

7 TJAQ-02-02-061-1 ja 1-

Attachment Pilot Pressure Sensor (Option)

TOJBQ40-EN-00(07/02/2020)

23-

MC Buzzer

45-

T2-2-85

MPDr. Monitor Controller

Monitor

SECTION2 SYSTEM Group2 Control System Overload Alarm Control (Option) Purpose: The overload alarm control sounds buzzer (8) and displays the overload alarm when boom raise operation such as hoisting is overloaded. Operation: 1. When all following conditions exist, MC (2) sends the signal to monitor controller (6). •

Overload alarm: Enable

•

Boom bottom pressure sensor (3): Outputting signal beyond the specified pressure

• Overload alarm switch (1): ON position 2. As long as receiving the signal from MC (2), monitor controller (6) connects terminal #D7 to the ground inside. 3. Monitor controller (6) sounds buzzer (8) and displays the overload alarm on monitor (7).

NOTE The alarm pressure setting (Tipping Threshold Boom CYL Bottom Pressure) of load in MC (2) can be adjusted by MPDr. (5). 3

4 7 2

6 D7

8 TDAA-02-02-013-1 ja 12-

Overload Alarm Switch MC

TOJBQ40-EN-00(07/02/2020)

Boom Bottom Pressure Sen sor

456-

T2-2-86

CAN MPDr. Monitor Controller

78-

Monitor Buzzer

SECTION2 SYSTEM Group3 Engine System Outline of ECM System ECM (19) receives the signals from sensors and MC (30). ECM (19) processes and activates two-way valve (20), suction control valve (26), EGR motor 1 (16), and EGR motor 2 (38) in order to control supply pump (24), injector (21), and the EGR valve. Supply pump (24) is activated by the engine and produces high-pressure fuel. Common rail (23) distributes high-pressure fuel produced by supply pump (24) to injector (21) in each engine cylinder. Injector (21) injects high-pressure fuel from common rail (23). 6

5 28 35 36

12 13 14

37 38

33 DCU 15 16 34

17 19 ECM 18

30 MC 22

CAN 27 29 26

21 23

24 25

1234567-

TOJBQ40-EN-00(07/02/2020)

89101112131415161718-

Crank Speed Sensor Cam Angle Sensor Coolant Temperature Sensor Boost Pressure Sensor Boost Temperature Sensor Engine Oil Pressure Sensor Intake Manifold Temperature Sensor EGR Motor Position Sensor 1 EGR Motor 1 Intake Throttle Position Sen sor Intake Throttle

19202122232425262728293031-

T2-3-1

ECM Two-Way Valve Injector Common Rail Pressure Sensor Common Rail Supply Pump Fuel Tank Suction Control Valve Fuel Temperature Sensor Differential Pressure Sensor Engine Oil Level Switch MC VGS Controller

32333435363738-

TJAQ-02-03-001-1 ja VGS Actuator DCU Atmospheric Pressure Sensor (Inside of ECM) EGR Cooler Inlet Temperature Sensor 2 EGR Cooler Outlet Tempera ture Sensor 2 EGR Motor Position Sensor 2 EGR Motor 2

SECTION2 SYSTEM Group3 Engine System Fuel Injection Control ECM (19) detects the engine running condition according to the signals from each sensor and MC (30). ECM (19) controls fuel injection amount, injection pressure, injection timing, and injection rate according to the engine running condition. The fuel injection control consists of the followings. •

Fuel Injection Amount Control

•

Fuel Injection Timing Control

•

Fuel Injection Rate Control

•

Fuel Injection Pressure Control 6

5 28 35 36

12 13 14

37 38

33 DCU 15 16 34

17 19 ECM 18

30 MC 22

CAN 27 29 26

21 23

24 25

TJAQ-02-03-001-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-3-2

SECTION2 SYSTEM Group3 Engine System 1234567-

89101112131415161718-

19202122232425262728293031-

32333435363738-

VGS Actuator DCU Atmospheric Pressure Sensor (Inside of ECM) EGR Cooler Inlet Temperature Sensor 2 EGR Cooler Outlet Tempera ture Sensor 2 EGR Motor Position Sensor 2 EGR Motor 2

Fuel Injection Amount Control Purpose: The fuel injection amount control controls the fuel injection amount appropriately. Operation: 1. ECM (19) detects the engine speed according to the signals from crank speed sensor (8) and cam angle sensor (9). 2. MC (29) calculates the target engine speed according to the signals from engine control dial (41), sensors, and switches. MC (29) sends the signal equivalent to the calculated target engine speed to ECM (19). (Refer to SYSTEM/ Control System.) 3. ECM (19) mainly controls fuel injection amount by turning two-way valve (20) in injector (21) ON/OFF according to the engine speed and the signal from MC (29).

TOJBQ40-EN-00(07/02/2020)

T2-3-3

SECTION2 SYSTEM Group3 Engine System 6 52 51 50 49 48 47 46 45 44

43 42 38 37

5 28 58 59

12 13 14 57 60

54 DCU

30 53

15 17 19 ECM

29 MC

CAN 32 41 40

56 SW-BOX

MODE

39 26

35 33

23 21

34 25

TJAQ-02-03-002-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-3-4

SECTION2 SYSTEM Group3 Engine System 1234567891011121314-

EGR Cooler Inlet Temperature Sensor 1 EGR Cooler Outlet Tempera ture Sensor 1 Intake-Air Temperature Sen sor MAF Sensor Intercooler Inlet Temperature Sensor DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Crank Speed Sensor Cam Angle Sensor Coolant Temperature Sensor Boost Pressure Sensor Boost Temperature Sensor Engine Oil Pressure Sensor Intake Manifold Temperature Sensor

TOJBQ40-EN-00(07/02/2020)

15161718192021222324252627282930313233-

EGR Motor Position Sensor 1 EGR Motor 1 Intake Throttle Position Sen sor Intake Throttle ECM Two-Way Valve Injector Common Rail Pressure Sensor Common Rail Supply Pump Fuel Tank Suction Control Valve Fuel Temperature Sensor Differential Pressure Sensor MC VGS Controller VGS Actuator Monitor Controller Pump 2 Delivery Pressure Sensor

3435363738394041424344454647-

T2-3-5

Pump 2 Displacement Control Pressure Sensor Pump 1 Delivery Pressure Sensor Pump 1 Displacement Control Pressure Sensor 4-Spool Pilot Pressure Sensor 5-Spool Pilot Pressure Sensor Auto-Idle Switch Power Mode Switch Engine Control Dial Arm Roll-Out Pilot Pressure Sensor Front Pilot Pressure Sensor Attachment Pilot Pressure Sensor (Option) Boom Lower Pilot Pressure Sensor Travel Pilot Pressure Sensor Swing Pilot Pressure Sensor

48495051525354555657585960-

Bucket Roll-Out Pilot Pressure Sensor Bucket Roll-In Pilot Pressure Sensor Arm Roll-In Pilot Pressure Sen sor Boom Raise Pilot Pressure Sensor Hydraulic Oil Temperature Sensor Engine Oil Level Switch DCU Atmospheric Pressure Sensor (Inside of ECM) Switch Box Controller EGR Motor Position Sensor 2 EGR Cooler Inlet Temperature Sensor 2 EGR Cooler Outlet Tempera ture Sensor 2 EGR Motor 2

SECTION2 SYSTEM Group3 Engine System Fuel Injection Timing Control Purpose: The fuel injection timing control controls the fuel injection timing properly. Operation: 1. ECM calculates the fuel injection timing according to the engine speed and fuel injection amount. 2. ECM turns two-way valve (2) in the injector ON/OFF according to fuel injection timing.

TOJBQ40-EN-00(07/02/2020)

T2-3-6

SECTION2 SYSTEM Group3 Engine System 1 9

1 2

8 7

5 10 11

9 8

7 5

123-

From ECM Two-Way Valve Returning to Fuel Tank

TOJBQ40-EN-00(07/02/2020)

456-

Orifice A Control Chamber Nozzle

789-

T2-3-7

From Common Rail Valve Electromagnetic Coil

101112-

TDC1-02-03-002-1 ja Hydraulic Piston Spring Orifice B

SECTION2 SYSTEM Group3 Engine System Fuel Injection Rate Control Purpose: The fuel injection rate control controls the fuel injection timing and fuel injection amount, and sets proper combustion in the engine cylinder. Operation: 1. The injector injects small amount of fuel (pilot injection) first and ignites. 2. After igniting, the injector makes second fuel injection (main injection). 3. ECM turns two-way valve (2) in the injector ON/OFF. Consequently, ECM controls the proper fuel injection timing and fuel injection amount. Operation of Fuel Injection: 1. Fuel pressure is always applied to nozzle (6) in the injector. 2. When turning ON electromagnetic coil (9) in two-way valve (2), high-pressure fuel in control chamber (5) returns to the fuel tank through orifice A (4). 3. As the pressure in control chamber (5) decreases, hydraulic piston (10) is raised and nozzle (6) is opened so that the injection starts. 4. When turning OFF electromagnetic coil (9) in two-way valve (2), valve (8) is closed and the circuit to the fuel tank is closed. High-pressure fuel from the common rail flows to control chamber (5) through orifice B (12). 5. As high-pressure fuel flows to control chamber (5), the pressure difference occurs to the upper and lower parts of hydraulic piston (10). Hydraulic piston (10) is lowered by this pressure difference.As nozzle (6) is closed, the injection stops.

TOJBQ40-EN-00(07/02/2020)

T2-3-8

SECTION2 SYSTEM Group3 Engine System 1

8 7

5 10 11

9 8

7 5

123-

From ECM Two-Way Valve Returning to Fuel Tank

456-

Orifice A Control Chamber Nozzle

789-

From Common Rail Valve Electromagnetic Coil

Fuel Injection Pressure Control Purpose: The fuel injection pressure control controls the fuel injection pressure appropriately. TOJBQ40-EN-00(07/02/2020)

T2-3-9

101112-

TDC1-02-03-002-1 ja Hydraulic Piston Spring Orifice B

SECTION2 SYSTEM Group3 Engine System Operation: 1. ECM (19) calculates fuel injection amount according to the engine speed and the signals from MC (29). (Refer to "Fuel Injection Control"T2-3-2.) 2. Common rail pressure sensor (22) sends the signals according to pressure in common rail (23) to ECM (19). 3. ECM (19) calculates the appropriate fuel pressure in common rail (23) according to the engine speed, fuel injection amount, and the signals of common rail pressure sensor (22). 4. ECM (19) activates suction control valve (26) in supply pump (24) and supplies the appropriate amount of fuel to common rail (23). 5. Fuel according to fuel pressure in common rail (23) is supplied to injector (21) from common rail (23) so that fuel injection pressure is controlled. 6 52 51 50 49 48 47 46 45 44

43 42 38 37

5 28 58 59

12 13 14 57 60

54 DCU

30 53

15 17 19 ECM

29 MC

CAN 32 41 40

56 SW-BOX

MODE

39 26

35 33

23 21

34 25

TJAQ-02-03-003-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-3-10

SECTION2 SYSTEM Group3 Engine System 1234567891011121314-

15161718192021222324252627282930313233-

3435363738394041424344454647-

48495051525354555657585960-

Fuel Injection Amount Correction Control Purpose: The fuel injection amount correction control appropriately corrects the fuel injection amount and the proper fuel injection timing. Operation: 1. When the engine starts, if the engine speed is lower than the engine start correction speed, ECM (19) corrects the fuel injection amount. (Start Correction) 2. In addition, ECM (19) corrects fuel injection amount according to the signals from atmospheric pressure sensor (34) (inside of ECM). (High Altitude Correction) 3. ECM (19) controls two-way valve (20) in injector (21) and controls the appropriate fuel injection amount.

TOJBQ40-EN-00(07/02/2020)

T2-3-11

SECTION2 SYSTEM Group3 Engine System 6

5 28 35 36

12 13 14

37 38

33 DCU 15 16 34

17 19 ECM 18

30 MC 22

CAN 27 29 26

21 23

24 25

1234567-

TOJBQ40-EN-00(07/02/2020)

89101112131415161718-

19202122232425262728293031-

T2-3-12

32333435363738-

TJAQ-02-03-004-1 ja VGS Actuator DCU Atmospheric Pressure Sensor (Inside of ECM) EGR Cooler Inlet Temperature Sensor 2 EGR Cooler Outlet Tempera ture Sensor 2 EGR Motor Position Sensor 2 EGR Motor 2

SECTION2 SYSTEM Group3 Engine System EGR Control Purpose: The EGR control re-circulates a part of exhaust gas into intake manifold (12), and mixes it with intake-air. Therefore, combustion temperature is lowered and generation of oxide of nitrogen (NOx) is controlled. Operation: •

EGR gas amount control 1. ECM (13) decides EGR gas amount according to engine speed, fuel flow rate, intake manifold temperature, coolant temperature, atmospheric pressure, and intake-air temperature. 2. ECM (13) activates EGR motor (10), opens EGR valve (8), and sends EGR gas to intake manifold (12) in response to engine condition. EGR gas and intake-air will mix in intake manifold (12). 3. At the same time, ECM (13) detects the opening amount of EGR valve (8) by using EGR motor position sensor (9).

•

EGR gas cooling 1. EGR gas is cooled by EGR cooler (6) in the EGR gas passage. 2. Cooled EGR gas and intake-air are mixed so that combustion temperature is lowered and NOx is generated lower than normal EGR gas.

NOTE EGR: Exhaust Gas Recirculation NOTE The MAF (Mass Air Flow) sensor forms an integral part with the intake-air temperature sensor. The MAF (Mass Air Flow) sensor detects intake-air amount from the air cleaner.

TOJBQ40-EN-00(07/02/2020)

T2-3-13

SECTION2 SYSTEM Group3 Engine System 2

3 21 5 6 4 7 22 8

12 9 11

13 14

20 15

19 18 17 16 123456-

From Air Cleaner To Intercooler Exhaust (To Aftertreatment Device) Engine Outlet of Coolant EGR Cooler

TOJBQ40-EN-00(07/02/2020)

789101112-

Inlet of Coolant EGR Valve EGR Motor Position Sensor EGR Motor Intake-Air (From Suction In tercooler) Intake Manifold

1314151617-

T2-3-14

ECM Atmospheric Pressure Sensor MAF/Intake-Air Temperature Sensor Intake Manifold Temperature Sensor Common Rail Pressure Sensor

1819202122-

TDC2-02-03-013-1 ja Coolant Temperature Sensor Cam Angle Sensor Crank Speed Sensor EGR Cooler Inlet Temperature Sensor EGR Cooler Outlet Tempera ture Sensor

SECTION2 SYSTEM Group3 Engine System Preheating Control Purpose: The preheating control controls glow plugs (8) which allows easier cold weather starting, reduces white smoke and noise at start up. And the preheating control adjusts length of time the glow plugs (8) are used to stabilize engine idle after start up. Operation: 1. ECM (3) receives the signals from intake-air temperature sensor (1) and coolant temperature sensor (2). 2. When the key switch is set to the ON position, current from terminal M (4) in the key switch flows to glow plug relay (7). 3. ECM (3) turns glow plug relay ON according to the signals from intake-air temperature sensor (1) and coolant temperature sensor (2). 4. ECM (3) controls time for current continuity to glow plug relay (7) so that, time for current continuity of glow plug (8) is controlled. 1

5 3 16

8 TDAA-02-03-010-1 ja 12-

Intake-Air Temperature Sen sor Coolant Temperature Sensor

TOJBQ40-EN-00(07/02/2020)

345-

ECM From Key Switch Terminal M Fuse Box

678-

T2-3-15

From Battery Glow Plug Relay Glow Plug

SECTION2 SYSTEM Group3 Engine System Variable Turbocharger Control Purpose: The variable turbocharger control controls the opening of nozzle inside of the turbine housing according to the engine speed and load. The inlet opening area of turbocharger and, the turbine speed are changed according to the opening of nozzle and supercharging pressure is controlled properly. Consequently, efficient turbocharging is obtained even the engine is running in slow speed.

TOJBQ40-EN-00(07/02/2020)

T2-3-16

SECTION2 SYSTEM Group3 Engine System Alarm Control Operation: 1. ECM (5) receives the signals from engine oil pressure sensor (3), boost temperature sensor (2), fuel temperature sensor (4), and common rail pressure sensor (9). 2. ECM (5) sends the signals to monitor controller (7) according to the signals from each sensor by using CAN communication (6). 3. Monitor controller (7) displays each alarm on monitor (1). 9 2 3 4 6 1 5

12-

Monitor Boost Temperature Sensor

34-

Engine Oil Pressure Sensor Fuel Temperature Sensor

56-

ECM CAN

79-

TDC4-02-03-009-1 ja Monitor Controller Common Rail Pressure Sensor

Urea SCR System The urea SCR system injects DEF into the exhaust of engine (1) to convert NOx into nitrogen and water. Therefore, the urea SCR system reduces NOx from exhaust gas. DCU (22) controls the urea SCR system. DCU (22) drives DEF supply module (20) and dosing module (8) according to the signals from sensors and ECM (24) to control following functions. DEF supply module (20) pumps DEF from DEF tank (14) to dosing module (8). Dosing module (8) injects DEF according to the signal from DCU (22). ● DEF Injection Control ● Start-Up Control ● DEF Defrosting Control ● DEF Thermal Control ● After-Run Control

TOJBQ40-EN-00(07/02/2020)

T2-3-17

SECTION2 SYSTEM Group3 Engine System 10

1 8 23 27

Local-CAN

11 12 28

18 13

22 DCU

24 ECM

ISO-CAN 19

DEF Pressure Sensor DEF Supply Module Tempera ture Sensor DEF Supply Module Coolant Control Valve DCU Differential Pressure Sensor ECM Monitor Controller MC

27-

17 16 15

26 MC

Power-CAN 1234567-

Engine DOC (Diesel Oxidation Cata lyst) DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Upstream NOx Sensor SCR Catalyst SCR Exhaust Temperature Sensor

891011121314151617-

29 Dosing module Upstream NOx Sensor Con troller Filter (CSF) DEF Piping DEF Sensor Unit Controller DEF Sensor Unit DEF Tank DEF Tank Level Sensor DEF Tank Temperature Sensor DEF Quality Sensor

181920212223242526-

2829303132-

TJAQ-02-03-006-1 ja Differential Pressure Detec tion Port Coolant Piping MAF/Intake-Air Temperature Sensor Reverting Valve Downstream NOx Sensor Downstream NOx Sensor Controller

DEF Injection Control Purpose: The DEF injection control controls the appropriate injection amount of DEF. Operation: 1. Upstream NOx sensor (5) detects the concentration of NOx in exhaust gas. 2. Upstream NOx sensor controller (9) sends the signal from upstream NOx sensor (5) to DCU (22) by using Local-CAN. 3. MAF/intake-air temperature sensor (29) detects intake-air flow rate from the air cleaner. 4. ECM (24) sends the signal from MAF/intake-air temperature sensor (29) to DCU (22) by using ISO-CAN. 5. DCU (22) controls dosing module (8) and to inject an appropriate DEF amount according to the signal.

TOJBQ40-EN-00(07/02/2020)

T2-3-18

SECTION2 SYSTEM Group3 Engine System 10

1 8 23 27

Local-CAN

11 12 28

18 13

22 DCU

24 ECM

ISO-CAN 19

DEF Pressure Sensor DEF Supply Module Tempera ture Sensor DEF Supply Module Coolant Control Valve DCU Differential Pressure Sensor ECM Monitor Controller MC

27-

17 16 15

26 MC

Power-CAN 1234567-

Engine DOC (Diesel Oxidation Cata lyst) DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Upstream NOx Sensor SCR Catalyst SCR Exhaust Temperature Sensor

891011121314151617-

29 Dosing module Upstream NOx Sensor Con troller Filter (CSF) DEF Piping DEF Sensor Unit Controller DEF Sensor Unit DEF Tank DEF Tank Level Sensor DEF Tank Temperature Sensor DEF Quality Sensor

181920212223242526-

2829303132-

TJAQ-02-03-007-1 ja Differential Pressure Detec tion Port Coolant Piping MAF/Intake-Air Temperature Sensor Reverting Valve Downstream NOx Sensor Downstream NOx Sensor Controller

Start-Up Control Purpose: The start-up control increases pressure of DEF for injection. Operation: 1. SCR exhaust temperature sensor (7) detects the inlet temperature of SCR catalyst (6). 2. DCU (22) activates DEF supply module (20) when the inlet temperature of SCR catalyst (6) becomes the specified value or higher. 3. DEF supply module (20) supplies the pressurized DEF to dosing module (8).

TOJBQ40-EN-00(07/02/2020)

T2-3-19

SECTION2 SYSTEM Group3 Engine System 10

1 8 23 27

Local-CAN

11 12 28

18 13

22 DCU

24 ECM

ISO-CAN 19

DEF Pressure Sensor DEF Supply Module Tempera ture Sensor DEF Supply Module Coolant Control Valve DCU Differential Pressure Sensor ECM Monitor Controller MC

27-

17 16 15

26 MC

Power-CAN 1234567-

Engine DOC (Diesel Oxidation Cata lyst) DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Upstream NOx Sensor SCR Catalyst SCR Exhaust Temperature Sensor

891011121314151617-

29 Dosing module Upstream NOx Sensor Con troller Filter (CSF) DEF Piping DEF Sensor Unit Controller DEF Sensor Unit DEF Tank DEF Tank Level Sensor DEF Tank Temperature Sensor DEF Quality Sensor

181920212223242526-

2829303132-

TJAQ-02-03-008-1 ja Differential Pressure Detec tion Port Coolant Piping MAF/Intake-Air Temperature Sensor Reverting Valve Downstream NOx Sensor Downstream NOx Sensor Controller

DEF Defrosting Control Purpose: The DEF defrosting control circulates coolant and defrosts DEF when DEF may freeze. Operation: 1. When DEF tank temperature sensor (16), DEF supply module temperature sensor (19) or MAF/intake-air temperature sensor (29) is at or below the specified detection temperature value, DCU (22) opens coolant control valve (21). 2. Heated coolant from engine (1) flows into DEF tank (14) through coolant control valve (21) and DEF supply module (20). 3. Coolant is circulated and DEF is defrosted. TOJBQ40-EN-00(07/02/2020)

T2-3-20

SECTION2 SYSTEM Group3 Engine System 4. DCU (22) performs start-up control when a predetermined time has elapsed. (Refer to "Start-Up Control"T2-3-19.) 5. When the DEF pressure that has increased because of the start-up control reaches a certain level or higher, DCU (22) closes coolant control valve (21). 10

1 8 23 27

Local-CAN

11 12 28

18 13

22 DCU

24 ECM

ISO-CAN 19

DEF Pressure Sensor DEF Supply Module Tempera ture Sensor DEF Supply Module Coolant Control Valve DCU Differential Pressure Sensor ECM Monitor Controller MC

27-

17 16 15

26 MC

Power-CAN 1234567-

Engine DOC (Diesel Oxidation Cata lyst) DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Upstream NOx Sensor SCR Catalyst SCR Exhaust Temperature Sensor

891011121314151617-

29 Dosing module Upstream NOx Sensor Con troller Filter (CSF) DEF Piping DEF Sensor Unit Controller DEF Sensor Unit DEF Tank DEF Tank Level Sensor DEF Tank Temperature Sensor DEF Quality Sensor

181920212223242526-

2829303132-

TJAQ-02-03-009-1 ja Differential Pressure Detec tion Port Coolant Piping MAF/Intake-Air Temperature Sensor Reverting Valve Downstream NOx Sensor Downstream NOx Sensor Controller

DEF Thermal Control Purpose: The DEF thermal control circulates coolant and defrosts DEF when DEF or intake-air temperature is at or below the specified value.

TOJBQ40-EN-00(07/02/2020)

T2-3-21

SECTION2 SYSTEM Group3 Engine System Operation: 1. When DEF tank temperature sensor (16) or MAF/intake-air temperature sensor (29) is at or below the specified detection temperature value, DCU (22) opens coolant control valve (21). 2. Heated coolant from engine (1) flows into DEF tank (14) through coolant control valve (21) and DEF supply module (20). 3. By this means, coolant is circulated and DEF is kept warm. 4. When DEF and intake-air temperatures become the specified values or higher, DCU (22) closes coolant control valve (21). 10

1 8 23 27

Local-CAN

11 12 28

18 13

22 DCU

24 ECM

ISO-CAN 19

DEF Pressure Sensor DEF Supply Module Tempera ture Sensor DEF Supply Module Coolant Control Valve DCU Differential Pressure Sensor ECM Monitor Controller MC

27-

17 16 15

26 MC

Power-CAN 1234567-

Engine DOC (Diesel Oxidation Cata lyst) DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Upstream NOx Sensor SCR Catalyst SCR Exhaust Temperature Sensor

TOJBQ40-EN-00(07/02/2020)

891011121314151617-

29 Dosing module Upstream NOx Sensor Con troller Filter (CSF) DEF Piping DEF Sensor Unit Controller DEF Sensor Unit DEF Tank DEF Tank Level Sensor DEF Tank Temperature Sensor DEF Quality Sensor

181920212223242526-

T2-3-22

2829303132-

TJAQ-02-03-010-1 ja Differential Pressure Detec tion Port Coolant Piping MAF/Intake-Air Temperature Sensor Reverting Valve Downstream NOx Sensor Downstream NOx Sensor Controller

SECTION2 SYSTEM Group3 Engine System After-Run Control Purpose: The after-run control returns DEF from DEF piping (11) to DEF tank (14) when the key switch is set to the OFF position. This prevents DEF from freezing and crystallizing in the piping. Operation: 1. When the key switch is set to the OFF position, DCU (22) turns ON reverting valve (30) and flow direction of DEF is changed. 2. DEF supply module (20) returns DEF from DEF piping (11) to DEF tank (14). 3. DCU (22) turns OFF DEF supply module (20) when the specified time (5 minutes) has passed. 4. Then, DCU (22) is turned OFF. 10

1 8 23 27

Local-CAN

11 12 28

18 13

22 DCU

24 ECM

ISO-CAN 19

DEF Pressure Sensor DEF Supply Module Tempera ture Sensor DEF Supply Module Coolant Control Valve DCU Differential Pressure Sensor ECM Monitor Controller MC

27-

17 16 15

26 MC

Power-CAN 1234567-

Engine DOC (Diesel Oxidation Cata lyst) DOC Inlet Exhaust Tempera ture Sensor DOC Outlet Exhaust Tempera ture Sensor Upstream NOx Sensor SCR Catalyst SCR Exhaust Temperature Sensor

TOJBQ40-EN-00(07/02/2020)

891011121314151617-

29 Dosing module Upstream NOx Sensor Con troller Filter (CSF) DEF Piping DEF Sensor Unit Controller DEF Sensor Unit DEF Tank DEF Tank Level Sensor DEF Tank Temperature Sensor DEF Quality Sensor

181920212223242526-

T2-3-23

2829303132-

TJAQ-02-03-011-1 ja Differential Pressure Detec tion Port Coolant Piping MAF/Intake-Air Temperature Sensor Reverting Valve Downstream NOx Sensor Downstream NOx Sensor Controller

SECTION2 SYSTEM Group3 Engine System Engine Output Restriction Control (INDUCEMENT) Purpose: When DEF level becomes low, or malfunction occurs on the urea SCR system or EGR system, the engine output restriction control displays the alarm on the monitor and sounds the buzzer. When the machine is continuously operated under this state, the engine output restriction control gradually decreases the engine torque and speed. Operation: 1. Signals from the urea SCR system are sent from DCU (33) to ECM (19) by using CAN communication. 2. When any one of the following conditions is met, ECM (19) decreases the engine torque. •

DEF level: 5% or less

•

Urea SCR System: Abnormal, certain time has elapsed

• EGR System: Abnormal, certain time has elapsed 3. In addition, ECM (19) sets the engine speed to the slow idle speed according to the level of DEF and elapsed time from the system error occurrence. 4. When the machine recovers to the normal condition, ECM (19) controls the engine torque and speed according to the other engine controls. 6

5 28 35 36

12 13 14

37 38

33 DCU 15 16 34

17 19 ECM 18

30 MC 22

CAN 27 29 26

21 23

24 25

TJAQ-02-03-005-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-3-24

SECTION2 SYSTEM Group3 Engine System 1234567-

89101112131415161718-

19202122232425262728293031-

32333435363738-

VGS Actuator DCU Atmospheric Pressure Sensor (Inside of ECM) EGR Cooler Inlet Temperature Sensor 2 EGR Cooler Outlet Tempera ture Sensor 2 EGR Motor Position Sensor 2 EGR Motor 2

Insufficient DEF Level 1. When the DEF level becomes 10% or lower, the engine output restriction control level is set to step 1. 2. An alarm is displayed on the monitor and the buzzer sounds once. 3. Then, the engine output restriction control level is set to the step 2 or step 3 depending on the remaining level of DEF. Engine Output Restriction Step 1 Control Level

Step 2

Step 3

DEF Level

10 % or less

5% or less

Engine Torque

No restriction

Restriction

Engine Speed

No restriction

Slow Idle

Buzzer

Sounds once

Sounds once/One second

Sounds continuously

Monitor Screen

 ˫

06 32 PM

50.0 h

81.3 MHz

TDFY-02-03-015 ja

 ˫

81.3 MH

TDFY-02-03-016 ja

 ˫

81.3 MH

TDFY-02-03-017 ja

Malfunction of Urea SCR System/Malfunction of EGR System 1. When malfunction occurs (first time) on the urea SCR system or EGR system, the engine output restriction control level is set to the step 1. 2. An alarm is displayed on the monitor and the buzzer sounds once. 3. Then, the engine output restriction control level is set to the step 2 or step 3 according to the elapsed time. 4. When malfunction of the urea SCR system or EGR system occurs, the ECM monitors the system condition for 40 hours after the recovery. 5. When malfunction occurs (second time) during this 40 hours after the recovery, the engine output restriction control level starts from the step 2 and transitional period to the step 3 is shortened.

TOJBQ40-EN-00(07/02/2020)

T2-3-25

SECTION2 SYSTEM Group3 Engine System NOTE The transitional period of the engine output restriction control level differs between the urea SCR system malfunction and EGR system malfunction. Engine Output Restric Step 1 tion Control Level

Step 2

Step 3

Malfunction of the - (Restriction starts.) Urea SCR System (First Time)

3 hours after starting the step 1 3.5 hours after starting the step 2

Malfunction of the Urea SCR System (Sec ond Time) (Within 40 Hours)

- (Restriction starts.)

Malfunction of the EGR - (Restriction starts.) System (First Time)

36 hours after starting the step 100 hours after starting the 1 step 2

Malfunction of the EGR System (Second Time) (Within 40 Hours)

- (Restriction starts.)

5 hours after starting the step 2

0.5 hours after starting the step 2

Engine Torque

No restriction

Restriction

Engine Speed

No restriction

Slow Idle

Buzzer

Sounds once

Sounds once/One second

Sounds continuously

Monitor Screen

 ˫

06 32 PM

50.0 h

 ˫

81.3 MHz

TDFY-02-03-018 ja

81.3 MHz

TDFY-02-03-019 ja

 ˫

81.3 MHz

TDFY-02-03-020 ja

Outline of Aftertreatment Device Aftertreatment device (16) consists of the diesel oxidation catalyst (DOC) block, filter (CSF) (14), and the SCR catalyst block. SCR catalyst 1 (11), SCR catalyst 2 (12), and the diesel oxidation catalyst (DOC) 2 (13) convert NOx in exhaust gas into nitrogen and water by a chemical reaction of NOx and DEF. Thus NOx is reduced from exhaust gas. Filter (14) removes fine particles (PM) in exhaust gas. Diesel oxidation catalyst (DOC) 1 (15) oxidizes unburnt fuel and raises exhaust temperature. Filter (14) traps PM, then burns and removes the PM using high temperature exhaust gas that was heated by diesel oxidation catalyst. Catalyst is applied onto filter (14). This promotes PM burning. DOC inlet exhaust temperature sensor (8) detects the exhaust temperature at upper stream of diesel oxidation catalyst (DOC) 1 (15). DOC outlet exhaust temperature sensor (7) detects the exhaust temperature at down stream of diesel oxidation catalyst (DOC) 1 (15). The differential pressure sensor (1) measures the differential pressure before and after filter (14) in order to detect the amount of trapped PM. Upstream NOx sensor (6) detects the concentration of NOx upstream of SCR catalyst 1 (11). TOJBQ40-EN-00(07/02/2020)

T2-3-26

SECTION2 SYSTEM Group3 Engine System Downstream NOx sensor (3) detects the concentration of NOx downstream of SCR catalyst 2 (12). Dosing module (5) injects DEF into aftertreatment device (16). SCR exhaust temperature sensor (9) detects the exhaust temperature at the upper stream of SCR catalyst 1 (11). 16

9 11 a

2 TJAQ-05-04-012-2 ja

a- Machine Front Side 1234-

Differential Pressure Sensor Downstream NOx Sensor Controller Downstream NOx Sensor Upstream NOx Sensor Con troller

5678-

Dosing module Upstream NOx Sensor DOC Outlet Exhaust Tempera ture Sensor DOC Inlet Exhaust Tempera ture Sensor

9101112-

SCR Exhaust Temperature Sensor Differential Pressure Detec tion Port SCR Catalyst 1 SCR Catalyst 2

13141516-

Diesel Oxidation Catalyst (DOC) 2 Filter (CSF) Diesel Oxidation Catalyst (DOC) 1 Aftertreatment Device

Operation of Aftertreatment Device 1. Exhaust gas combusted in the engine cylinders passes through the diesel oxidation catalyst (DOC) 1 (15) in aftertreatment device (16) and flows to filter (CSF) (14). 2. Diesel oxidation catalysts (DOC) 1 (15) reduce harmful substances contained in exhaust gas such as carbon monoxide by initiating a chemical reaction. 3. When the exhaust gas passes through filter (14), the PM is filtered out by filter (14). 4. PM that was filtered out by filter (14) accumulates inside filter (14). 5. The accumulated PM is removed when aftertreatment device (16) is regenerated, and is discharged as CO2. (Refer to "Aftertreatment Device Regeneration Control"T2-3-29) 6. DCU (17) controls dosing module (5) according to the signals from upstream NOx sensor (6). 7. Dosing module (5) injects DEF into aftertreatment device (16).

TOJBQ40-EN-00(07/02/2020)

T2-3-27

SECTION2 SYSTEM Group3 Engine System 8. At this time, DEF breaks down into ammonia (NH3) and carbon dioxide (CO2). 9. SCR catalysts 1 (11), SCR catalysts 2 (12) initiate a chemical reaction of ammonia (NH3) and NOx in exhaust gas so that NOx is broken down into nitrogen and water. 10. Oxidation catalyst (DOC) 2 (13) breaks down ammonia (NH3) into nitrogen (N2) and water (H2O). 11. As a result, NOx is reduced from exhaust gas and any remaining ammonia (NH3) is removed. 9

10 6 A 4 2 15 7

1 14 Local-CAN

18 ECM

17 DCU ISO-CAN

14 c CO2

TDFY-02-03-006-1 ja

a- Filtering b- Accumulation 12345-

Differential Pressure Sensor Downstream NOx Sensor Controller Downstream NOx Sensor Upstream NOx Sensor Con troller Dosing Module

TOJBQ40-EN-00(07/02/2020)

c- Regeneration 6789-

Upstream NOx Sensor DOC Outlet Exhaust Tempera ture Sensor DOC Inlet Exhaust Tempera ture Sensor SCR Exhaust Temperature Sensor

1011121314-

T2-3-28

Differential Pressure Detec tion Port SCR Catalyst 1 SCR Catalyst 2 Diesel Oxidation Catalyst (DOC) 2 Filter (CSF)

15161718-

Diesel Oxidation Catalyst (DOC) 1 Aftertreatment Device DCU ECM

SECTION2 SYSTEM Group3 Engine System Aftertreatment Device Regeneration Control Purpose: The Aftertreatment device regeneration control mixes unburnt fuel with exhaust gas, and initiates oxidation of unburnt fuel by using the diesel oxidation catalysts (DOC). This process increases exhaust gas temperature and performs regeneration. Aftertreatment device (16) regeneration includes self regeneration and forced regeneration. Forced regeneration includes auto regeneration and manual regeneration. •

NH3 reset: NH3 reset resets error between actual value and calculated value of NH3 adsorbed to the SCR catalyst.

•

Elimination of HC Poisoning: When activity of the diesel oxidation catalysts (DOC) is low in a cold weather, NH3 adsorption to the SCR catalyst may be blocked due to unburnt fuel (HC). Elimination of HC poisoning is performed by increasing the exhaust temperature.

•

Removal of white deposition: When the machine is operated with low exhaust temperature for long period of time, part of injected DEF may create white deposition. White deposition is removed by increasing the exhaust temperature.

•

Elimination of Sulfur Poisoning: When sulfur compound contained in fuel adheres to the diesel oxidation catalysts (DOC), the catalyst performance deteriorates. Elimination of Sulfur poisoning is performed by increasing the exhaust temperature.

•

Removal of PM: PM accumulated in filter (CSF) (14) is burnt and removed using heat of exhaust gas.

Operation (Self Regeneration): 1. Auto regeneration uses high temperature exhaust gas to perform regeneration without using the diesel oxidation catalyst (DOC) 1(15) function. 2. A higher exhaust temperature at the filter (CSF) (14) inlet results in greater activation of the catalyst, increasing the amount of regeneration. Operation (Forced Regeneration): 1. ECM (18) injects fuel (post injection (20)) to exhaust gas in engine cylinder (19), and exhaust gas mixed with unburnt fuel is supplied to diesel oxidation catalyst (DOC) (1) (12). 2. Diesel oxidation catalyst (DOC) 1 (12) oxidizes unburnt fuel and raises exhaust temperature. 3. Therefore, exhaust temperature of the outlet of diesel oxidation catalyst (DOC) 1 (12) raises up to about 600 °C and regeneration is carried out. Auto-Regeneration: •

The regeneration is automatically carried out every 15 hours. (Regeneration time: About 7 minutes (Regeneration Time)

•

When the output signal from differential pressure sensor (1) reaches a certain pressure level or more before 15 hours pass after the completion of the previous regeneration, forced regeneration is automatically carried out. (Differential pressure regeneration)

Manual Regeneration: •

When Manual Regeneration Request is displayed on the monitor, the regeneration is manually carried out by setting the engine control dial to the slow idle position, turning the pilot shut-off lever to the LOCK position, and by pushing the manual regeneration switch to the ON position. (Regeneration time: About 30 minutes)

TOJBQ40-EN-00(07/02/2020)

T2-3-29

SECTION2 SYSTEM Group3 Engine System

10 6

4 2 15 7

14 1

18 ECM

Local-CAN 17 DCU

ISO-CAN

23 TDFY-02-03-007-1 ja

a- Fuel Injection Amount

TOJBQ40-EN-00(07/02/2020)

T2-3-30

SECTION2 SYSTEM Group3 Engine System 123456-

Differential Pressure Sensor Downstream NOx Sensor Controller Downstream NOx Sensor Upstream NOx Sensor Con troller Dosing Module Upstream NOx Sensor

TOJBQ40-EN-00(07/02/2020)

78910-

DOC Outlet Exhaust Tempera ture Sensor DOC Inlet Exhaust Tempera ture Sensor SCR Exhaust Temperature Sensor Differential Pressure Detec tion Port

111213141516-

T2-3-31

SCR Catalyst 1 SCR Catalyst 2 Diesel Oxidation Catalyst (DOC) 2 Filter (CSF) Diesel Oxidation Catalyst (DOC) 1 Aftertreatment Device

17181920212223-

DCU ECM Cylinder Post Injection Main Injection Pilot Injection Multi Injection

SECTION2 SYSTEM Group3 Engine System MEMO

TOJBQ40-EN-00(07/02/2020)

T2-3-32

SECTION2 SYSTEM Group4 Hydraulic System Outline of Hydraulic System The hydraulic system mainly consists of the pilot circuit, main circuit, and breaker/crusher circuit. Pilot Circuit: Power Source Pilot Pump

Related Device

Supplied to

Pilot Valve Pump Regulator 4-Spool Solenoid Valve Unit Accumulator Signal Control Valve

Operation Control Circuit Pump Control Circuit Aftertreatment Device Regeneration Control Circuit Bucket Flow Combiner Circuit Valve Control Circuit Travel Motor Displacement Angle Control Circuit Swing Parking Brake Release Circuit Emergency Boom Lower Circuit

Main Circuit: Power Source Main Pump Fan Pump

Related Device Control Valve

Supplied to Motor Cylinder Fan Valve

Breaker/Crusher Circuit (Option): Power Source

Related Device

Supplied to

Pilot Pump

Pilot Valve

Auxiliary Flow Combiner Circuit Breaker Circuit Selector Valve Control Circuit

Main Pump

Control Valve

Attachment (Breaker, Crusher)

Pilot Circuit of Hydraulic System Pressure oil from the pilot pump is used in order to operate the following circuits. •

Operation Control Circuit

•

Pump Control Circuit

•

Aftertreatment Device Regeneration Control Circuit

•

Bucket Flow Combiner Circuit

•

Valve Control Circuit

•

Travel Motor Displacement Angle Control Circuit

•

Swing Parking Brake Release Circuit

•

Emergency Boom Lower Circuit

TOJBQ40-EN-00(07/02/2020)

T2-4-1

SECTION2 SYSTEM Group4 Hydraulic System 7 6

P1 P2 13 P1 P2 14 15 16

17 43

44 45 46

37 47

49 50

54 11 27 28

26 29

32 33

30 34 12345678910-

11131415-

Travel Pilot Valve Pilot Valve (Left) Pilot Valve (Right) Auxiliary Pilot Valve Shockless Valve Operation Control Circuit Swing Parking Brake Release Circuit Swing Motor Pump Control Circuit Pump 1 Control Solenoid Valve, Pump 2 Control Sole noid Valve Control Valve Regulator Spool Flow Combiner Valve

TOJBQ40-EN-00(07/02/2020)

16171819202122232425262728-

Boom Anti-Drift Valve Arm 1 Flow Rate Control Valve Arm 2 Flow Rate Control Valve Swing Flow Rate Control Valve Boom Overload Relief Valve Pump 2 Bypass Shut-Out Valve Pump 1 Bypass Shut-Out Valve Arm Regenerative Cut Valve Main Relief Valve Auxiliary Overload Relief Auxiliary Flow Combiner Valve Hydraulic Oil Tank Suction Filter

29303132333435363741424344-

T2-4-2

Pilot Pump Pilot Filter Pilot Relief Valve Valve Control Circuit Travel Motor Travel Motor Displacement Angle Control Circuit 4-Spool Solenoid Valve Unit 4-Spool Solenoid Valve Unit Aftertreatment Device Regen eration Control Circuit Signal Control Valve Pilot Shut-Off Solenoid Valve Arm 2 Flow Rate Control Sole noid Valve (SG) Swing Flow Rate Control Sole noid Valve (SI)

454647484950-

5455-

TJBQ-02-04-001-1 ja Boom Mode Selector Control Solenoid Valve (SF) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC) 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI) Main Relief Valve Control Sol enoid Valve (SF) Travel Motor Displacement Angle Control Solenoid Valve (SC) Fan Pump Control Solenoid Valve Fan Pump Regulator

SECTION2 SYSTEM Group4 Hydraulic System Operation Control Circuit 1. The pilot valve controls pressure oil from pilot pump (B1) and moves the spool in control valve (B0). 2. Signal control valve (A9) is provided between the pilot valve and control valve (B0). Boom raise shockless valve (A8) is provided in the boom raise circuit in signal control valve (A9). 3. Boom raise shockless valve (A8) restricts returning oil from control valve (B0) when the boom raise operation stops, and dampens the quick spool movement in control valve (B0). (Refer to COMPONENT OPERATION/Signal Control Valve.) 4. Boom lower shockless valve (A7) is provided between signal control valve (A9) and control valve (B0) in the boom lower circuit. 5. Boom lower shockless valve (A7) restricts returning oil from control valve (B0) when the boom lower operation stops, and dampens the quick spool movement in control valve (B0). (Refer to COMPONENT OPERATION/Signal Control Valve.)

TOJBQ40-EN-00(07/02/2020)

T2-4-3

SECTION2 SYSTEM Group4 Hydraulic System A0

A8 A7 A9

1112 9 10 7 8 4 3

1 6 5 14 13

2 12

B0 9

7 2

1 2 4

4 3 6

5 B1

TJAQ-02-04-002-1 ja 1234A0A1A2-

Boom Raise Boom Lower Arm Roll-Out Arm Roll-In Travel (Left) Travel (Right) Swing

5678A3A4A5-

Swing Left Swing Right Bucket Roll-In Bucket Roll-Out Arm Boom Bucket

9101112A6A7A8-

Travel Left Forward Travel Left Reverse Travel Right Forward Travel Right Reverse Auxiliary Boom Lower Shockless Valve Boom Raise Shockless Valve

Pump Control Circuit (Refer to COMPONENT OPERATION/Pump Device.) •

Pump Control by Pump Control Solenoid Valve

TOJBQ40-EN-00(07/02/2020)

T2-4-4

1314-

Auxiliary Auxiliary

A9- Signal Control Valve B0- Control Valve B1- Pilot Pump

SECTION2 SYSTEM Group4 Hydraulic System 1. Pilot pressure oil from pilot pump (5) is controlled by pump 1 control solenoid valve (4) and pump 2 control solenoid valve (1), and is supplied as pump displacement angle control pressure to the regulators of pump 1 (3) and pump 2 (2). 2. The regulators increase or decrease the pump delivery flow rate according to the pump displacement angle control pressure. •

Fan Pump Control by Fan Pump Control Solenoid Valve 1. Pilot pressure from pilot pump (5) is controlled by fan pump control solenoid valve (7), and is supplied as fan pump control pressure to the regulator of radiator fan pump (6). 2. The regulator increases or decreases the fan pump delivery flow rate according to the fan pump control pressure.

12-

Pump 2 Control Solenoid Valve Pump 2

34-

Pump 1 Pump 1 Control Solenoid Valve

56-

Pilot Pump Radiator Fan Pump

78-

TJBQ-02-04-002-1 ja Fan Pump Control Solenoid Valve Oil Cooler Fan Pump

Aftertreatment Device Regeneration Control Circuit (Refer to SYSTEM/Control System.) Purpose: As the aftertreatment device regeneration control circuit increases the pump load when performing aftertreatment device manual regeneration, the load is applied to the engine. Therefore, the exhaust temperature increases up to the temperature that a catalyst in the aftertreatment device is activated. •

Valve Control 1. When the aftertreatment device regeneration control conditions are satisfied, MC activates the 4-spool bypass shut-out control solenoid valve (SG) (7) and the 5-spool bypass shut-out control solenoid valve (SC) (8). 2. Pilot pressure oil shifts pump 1 bypass shut-out valve (3) and pump 2 bypass shut-out valve (10). 3. As neutral circuit (2) in pump 1 (4) and pump 2 (1) is partially blocked, the pressure of pump 1 (4) and pump 2 (1) increases.

•

Pump 1 (4) and Pump 2 (1) Delivery Flow Rate Control

TOJBQ40-EN-00(07/02/2020)

T2-4-5

SECTION2 SYSTEM Group4 Hydraulic System 1. When the conditions for aftertreatment device regeneration control exist, MC shifts pump 1 control solenoid valve (5) and pump 2 control solenoid valve (9). 2. Pilot pressure oil is supplied to the regulators in pump 1 (4) and pump 2 (1). The regulators in pump 1 (4) and pump 2 (1) increase the delivery flow rate. 3. Therefore, as the pump load increases, the load is applied to the engine. Consequently, the engine exhaust temperature increases and the aftertreatment device is regenerated. 10

1 3 4

5 6 123-

Pump 2 Neutral Circuit Pump 1 Bypass Shut-Out Valve

456-

Pump 1 Pump 1 Control Solenoid Valve Pilot Pump

78-

4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC)

910-

TJAQ-02-04-004-1 ja Pump 2 Control Solenoid Valve Pump 2 Bypass Shut-Out Valve

Bucket Flow Combiner Circuit (Refer to SYSTEM/Control System.) Purpose: The bucket flow combiner circuit combines pressure oil from pump 1 (3) and pump 2 (4) at bucket spool (5) when performing bucket single operation. Therefore, the bucket operating speed increases. 1. When performing bucket roll-in or roll-out operation, pilot pressure shifts bucket spool (5). 2. When the 5-spool bypass shut-out control solenoid valve (SC) (1) is activated, pilot pressure shifts the pump 2 bypass shut-out valve (2). 3. The neutral circuit of pump 2 (3) is blocked and pressure oil from pump 2 (4) is combined with pressure oil from pump 1 (3). 4. Therefore, the bucket operating speed increases. TOJBQ40-EN-00(07/02/2020)

T2-4-6

SECTION2 SYSTEM Group4 Hydraulic System

B A

5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC)

Pump 2 Bypass Shut-Out Valve

34-

Pump 1 Pump 2

56-

TJAQ-02-04-021-1 ja Bucket Spool Bucket Cylinder

Valve Control Circuit (Refer to COMPONENT OPERATION/Control Valve.) ● Pilot pressure from the pilot pump controls the following valves and spools after flowing through 4-spool bypass shutout control solenoid valve (SG) (23), arm regenerative control solenoid valve (SI) (24), main relief valve control solenoid valve (SF) (25), arm 2 flow rate control solenoid valve (SG) (13), swing flow rate control solenoid valve (SI) (14), boom

TOJBQ40-EN-00(07/02/2020)

T2-4-7

SECTION2 SYSTEM Group4 Hydraulic System mode selector control solenoid valve (SF) (17), 5-spool bypass shut-out control solenoid valve (SC) (22), and flow combiner valve control spool (7) inside signal control valve (6). •

4-spool Bypass Shut-Out Control Solenoid Valve (SG) (23): Pump 1 Bypass Shut-Out Valve (16)

•

Arm Regenerative Control Solenoid Valve (SI) (24): Arm Regenerative Cut Valve (20)

•

Main Relief Valve Control Solenoid Valve (SF) (25): Main Relief Valve (11)

•

Arm 2 Flow Rate Control Solenoid Valve (SG)(13): Arm 2 Flow Rate Control Valve (19)

•

Swing Flow Rate Control Solenoid Valve (SI) (14): Swing Flow Rate Control Valve (30)

•

Boom Mode Selector Control Solenoid Valve (SF) (17): Boom Overload Relief Valve (21)

•

5-spool Bypass Shut-Out Control Solenoid Valve (SC) (22): Pump 2 Bypass Shut-Out Valve (26)

•

Boom Lower Pilot Pressure (8): Boom Flow Rate Control Valve (12)

•

Flow Combiner Valve Control Spool (7) (Travel (Right) Pilot Pressure): Flow Combiner Valve (2)

•

Flow Rate Control Valve Control Spool (8) (Arm Roll-in Pilot Pressure, Swing Pilot Pressure): Arm 1 Flow Rate Control Valve (18)

TOJBQ40-EN-00(07/02/2020)

T2-4-8

SECTION2 SYSTEM Group4 Hydraulic System 1

13 14

7 26

10 9 11

22 23 24 25 27

19 30 31

20 16 TJBQ-02-04-003-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-4-9

SECTION2 SYSTEM Group4 Hydraulic System 12345678910-

Travel Right Reverse Travel Right Forward Arm Roll-In Arm Roll-Out Boom Lower Signal Control Valve Flow Combiner Valve Control Spool Boom Lower Pilot Pressure Arm Roll-Out Pilot Pressure Arm Roll-In Pilot Pressure

111213141617-

Main Relief Valve Flow Combiner Valve Arm 2 Flow Rate Control Sole noid Valve (SI) Swing Flow Rate Control Sole noid Valve (SI) Pump 1 Bypass Shut-Out Valve Boom Mode Selector Control Solenoid Valve (SF)

18192021222324-

Travel Motor Displacement Angle Control Valve Arm 2 Flow Rate Control Valve Arm Regenerative Cut Valve Boom Overload Relief Valve 5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC) 4-Spool Bypass Shut-Out Con trol Solenoid Valve (SG) Arm Regenerative Control Solenoid Valve (SI)

252627-

30-

Main Relief Valve Control Sol enoid Valve (SF) Pump 2 Bypass Shut-Out Valve Travel Motor Displacement Angle Control Solenoid Valve (SC) Swing Flow Rate Control Valve

Travel Motor Displacement Angle Control Circuit (Refer to COMPONENT OPERATION/Travel Device.) 1. Pilot pressure from travel motor displacement angle control solenoid valve (SC) (27) controls travel motor displacement angle control valve (18).

TOJBQ40-EN-00(07/02/2020)

T2-4-10

SECTION2 SYSTEM Group4 Hydraulic System 1

13 14

7 26

10 9 11

22 23 24 25 27

19 30 31

20 16 TJBQ-02-04-003-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-4-11

SECTION2 SYSTEM Group4 Hydraulic System 12345678910-

111213141617-

18192021222324-

252627-

30-

Main Relief Valve Control Sol enoid Valve (SF) Pump 2 Bypass Shut-Out Valve Travel Motor Displacement Angle Control Solenoid Valve (SC) Swing Flow Rate Control Valve

Swing Parking Brake Release Circuit (Refer to COMPONENT OPERATION/Swing Device.) 1. When operating the front attachment or swing, the pilot pressure from the pilot valve is selected by shuttle valve (7) inside signal control valve (6), and this pilot pressure shifts the swing parking brake release spool (8). 2. Consequently, pilot pressure SH from pilot pump (10) is supplied to swing motor (9) and releases the swing parking brake. 1

5 SH 6

TJAQ-02-04-006-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-4-12

SECTION2 SYSTEM Group4 Hydraulic System 123-

Swing Arm Boom

456-

Bucket Orifice Signal Control Valve

78-

Shuttle Valve Swing Parking Brake Release Spool

91011-

Swing Motor Pilot Pump Pilot Shut-Off Solenoid Valve

Emergency Boom Lower Circuit (Refer to COMPONENT OPERATION/Others (Upperstructure).) Purpose: Accumulator (8) and check valve (11) for preventing back flow are provided between pilot pump (6) and pilot shut-off solenoid valve (10). Accumulator (8) stores pilot oil from pilot pump (6) under pressure. This makes it possible to perform emergency boom lower operation. 1. After the engine stopped suddenly, when boom lower operation is performed with the pilot shut-off lever in the UNLOCK position, pressure oil from accumulator (8) passes through pilot valve (1) and acts as boom lower pilot pressure (2) on boom 1 spool (4) and boom 2 spool (7) of control valve (3). 2. Boom 1 spool (4) and boom 2 spool (7) of control valve (3) are activated, and the boom cylinder (9) circuit is connected to hydraulic oil tank (5). This allows the front attachment to be lowered to the ground (due to its own weight) by quickly performing boom lower operation even when the engine stopped suddenly.

NOTE Immediately after engine stop (key switch OFF), activation of the load dump relay causes the battery relay to turn ON for a certain length of time. (Refer to SYSTEM/Electrical System/"Surge Voltage Prevention Circuit"T2-5-9.) As a result, current from the battery (fuse #4) flows to the pilot shut-off solenoid valve, and the pilot shut-off solenoid valve remains ON.

TOJBQ40-EN-00(07/02/2020)

T2-4-13

SECTION2 SYSTEM Group4 Hydraulic System 1

9 10

2 11 3

7 2

2 6

TJAQ-02-04-022-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-4-14

SECTION2 SYSTEM Group4 Hydraulic System 1 2 3

Pilot Valve Boom Lower Pilot Pressure Control Valve

4 5 6

Boom 1 Spool Hydraulic Oil Tank Pilot Pump

7 8 9

Boom 2 Spool Accumulator Boom Cylinder

10 11

Pilot Shut-Off Solenoid Valve Check Valve

Main Circuit of Hydraulic System 1. The main pump draws hydraulic oil from hydraulic oil tank (23) and delivers it to control valve (6). 2. Pressure oil from pump 1 (20) flows to 4-spool side of control valve (6) and then to travel (right) spool (12), bucket spool (13), boom 1 spool (14), and arm 2 spool (15). 3. Pressure oil from pump 2 (19) flows to 5-spool side of control valve (6) and then to swing spool (11), arm 1 spool (10), boom 2 spool (9), auxiliary spool (8), and travel (left) spool (7). 4. Delivered hydraulic oil is supplied to the motors or cylinders in response to the spool operation of control valve (6). 5. Returning oil from the motors or cylinders returns to hydraulic oil tank (23) through control valve (6), low-pressure relief valve (26), and oil cooler (25). 6. When the oil temperature is low (high viscosity) and the oil flow resistance increases in oil cooler (21), bypass check valve (24) is opened and hydraulic oil directly returns to hydraulic oil tank (23). 7. Radiator Fan pump (17) draws hydraulic oil from hydraulic oil tank (23) and delivers it to Radiator fan motor (25). 8. Oil cooler Fan pump (32) draws hydraulic oil from hydraulic oil tank (23) and delivers it to Oil cooler fan motor (31).

TOJBQ40-EN-00(07/02/2020)

T2-4-15

SECTION2 SYSTEM Group4 Hydraulic System 2

4 18 7

26 17

20 21

25 24 27

28 123456789-

Travel Motor (Left) Travel Motor (Right) Bucket Cylinder Boom Cylinder Swing Motor Control Valve Travel (Left) Spool Auxiliary Spool Boom 2 Spool

TOJBQ40-EN-00(07/02/2020)

101112131415161718-

Arm 1 Spool Swing Spool Travel (Right) Spool Bucket Spool Boom 1 Spool Arm 2 Spool Attachments Radiator Fan Pump Arm Cylinder

1920212223242526-

T2-4-16

Pump 2 Pump 1 Oil Cooler Suction Filter Hydraulic Oil Tank Bypass Check Valve Radiator Fan Motor Low-Pressure Relief Valve

27282930313233-

TJBQ-02-04-004-1 ja Fan Speed Control Solenoid Valve Oil Cooler Fan Control Valve Fan Reverse Rotation Control Solenoid Valve 2 Reverse Rotation Spool Oil Cooler Fan Motor Oil Cooler Fan Pump Oil Cooler Fan Valve

SECTION2 SYSTEM Group4 Hydraulic System Neutral Circuit 1. When the control lever is in neutral, pressure oil from the main pump returns to hydraulic oil tank (24) through the control valve. 2. Parallel circuits (8, 19) are provided in each circuit of pump 1 (22), and pump 2 (21) so that combined operation becomes possible. 31

28 13

B A

5 7

25 17 32 14

30 34 12

35 29 24

2 18

9 21

22 TJBQ-02-04-006-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-4-17

SECTION2 SYSTEM Group4 Hydraulic System 12345678910-

Main Relief Valve Flow Combiner Circuit (Arm) Travel Motor (Right) Travel (Right) Spool Bucket Spool Bucket Cylinder Overload Relief Valve (Bucket: Rod Side) Parallel Circuit (Pump 1) Arm 2 Spool Neutral Circuit (Pump 1)

111213141516171819-

Boom 1 Spool Boom Cylinder Auxiliary Overload Relief Valve Boom 2 Spool Swing Motor Swing Spool Boom Overload Relief Valve (Boom 2: Rod Side) Flow Combiner Circuit (Boom) Parallel Circuit (Pump 2)

202122232425262728-

Neutral Circuit (Pump 2) Pump 2 Pump 1 Travel (Left) Spool Hydraulic Oil Tank Auxiliary Overload Relief Valve Auxiliary Spool Arm 1 Spool Attachment

29303132333435-

Overload Relief Valve (Arm: Bottom Side) Arm Cylinder Travel Motor (Left) Overload Relief Valve (Bucket: Bottom Side) Overload Relief Valve (Boom 1: Bottom Side) Overload Relief Valve (Arm: Rod Side) Low Pressure Relief Valve

Flow Combiner Circuit 1. When performing boom raise and arm operations, pressure oil from two pumps, pump 1 (22) and pump 2 (21), is combined. 2. When performing boom lower operation, pressure oil from pump 2 (21) is not combined, but pressure oil from pump 1 (22) and boom cylinder (12) bottom side is combined. (Boom lower regenerative circuit)

TOJBQ40-EN-00(07/02/2020)

T2-4-18

SECTION2 SYSTEM Group4 Hydraulic System 31

28 13

B A

5 7

25 17 32 14

30 34 12

35 29 24

2 18

9 21

12345678910-

TOJBQ40-EN-00(07/02/2020)

111213141516171819-

Boom 1 Spool Boom Cylinder Auxiliary Overload Relief Valve Boom 2 Spool Swing Motor Swing Spool Boom Overload Relief Valve (Boom 2: Rod Side) Flow Combiner Circuit (Boom) Parallel Circuit (Pump 2)

202122232425262728-

T2-4-19

Neutral Circuit (Pump 2) Pump 2 Pump 1 Travel (Left) Spool Hydraulic Oil Tank Auxiliary Overload Relief Valve Auxiliary Spool Arm 1 Spool Attachment

29303132333435-

TJBQ-02-04-006-1 ja Overload Relief Valve (Arm: Bottom Side) Arm Cylinder Travel Motor (Left) Overload Relief Valve (Bucket: Bottom Side) Overload Relief Valve (Boom 1: Bottom Side) Overload Relief Valve (Arm: Rod Side) Low-Pressure Relief Valve

SECTION2 SYSTEM Group4 Hydraulic System Relief Circuit 1. Main relief valve (1) is provided in the main circuit. 2. Main relief valve (1) prevents the pressure in the main circuit from exceeding the set pressure when the spool is operated (or when the control lever is operated). 3. Overload relief valves (7, 13, 17, 25, 29, 32, 33, 34) are provided in the actuator circuit (between the control valve and the actuator) of the boom, arm, and bucket. 4. Overload relief valves (7, 13, 17, 25, 29, 32, 33, 34) prevent the pressure caused by external force in the actuator circuit from exceeding the set pressure. 5. Overload relief valves (7, 13, 17, 25, 29, 32, 33, 34) include a make-up function. When the pressure in the actuator circuit decreases, overload relief valves (7, 13, 17, 25, 29, 32, 33, 34) draw pressure oil from hydraulic oil tank (24) and prevent cavitation from occurring. 6. Low-pressure relief valve (35) is provided in the return circuit of the main circuit (between the control valve and the oil cooler). 7. Low-pressure relief valve (35) maintains a constant pressure in the main circuit, improving the absorption ability of the actuator in case of cavitation.

TOJBQ40-EN-00(07/02/2020)

T2-4-20

SECTION2 SYSTEM Group4 Hydraulic System 31

28 13

B A

5 7

25 17 32 14

30 34 12

35 29 24

2 18

9 21

12345678910-

TOJBQ40-EN-00(07/02/2020)

111213141516171819-

Boom 1 Spool Boom Cylinder Auxiliary Overload Relief Valve Boom 2 Spool Swing Motor Swing Spool Boom Overload Relief Valve (Boom 2: Rod Side) Flow Combiner Circuit (Boom) Parallel Circuit (Pump 2)

202122232425262728-

T2-4-21

Neutral Circuit (Pump 2) Pump 2 Pump 1 Travel (Left) Spool Hydraulic Oil Tank Auxiliary Overload Relief Valve Auxiliary Spool Arm 1 Spool Attachment

29303132333435-

SECTION2 SYSTEM Group4 Hydraulic System Combined Operation Circuit •

Swing, Boom Raise 1. When the boom is raised while swinging, the pilot pressure shifts swing spool (6), boom 1 spool (2), and boom 2 spool (5). 2. Pressure oil from pump 1 (8) flows to boom cylinders (3) through parallel circuit (1) and boom 1 spool (2) and raises the boom. 3. Pressure oil from pump 2 (7) flows to boom cylinders (3) through parallel circuit (9) and boom 2 spool (5), and raises the boom. 4. Pressure oil from pump 2 (7) flows to swing motor (4) through swing spool (6) and swings the machine. At the same time, pressure oil from pump 2 (7) flows through parallel circuit (9) and boom 2 spool (5), is combined with pressure oil from pump 1 (8), flows to boom cylinders (3), and raises the boom.

TOJBQ40-EN-00(07/02/2020)

T2-4-22

SECTION2 SYSTEM Group4 Hydraulic System 3

B A

8 TJAQ-02-04-009-1 ja

123-

Parallel Circuit (Pump 1) Boom 1 Spool Boom Cylinder

TOJBQ40-EN-00(07/02/2020)

456-

Swing Motor Boom 2 Spool Swing Spool

789-

T2-4-23

Pump 2 Pump 1 Parallel Circuit (Pump 2)

SECTION2 SYSTEM Group4 Hydraulic System Flow Combiner Circuit Purpose: The flow combiner circuit shifts flow combiner valve (4) when performing combined operation of travel and front attachment or combined operation of travel and swing, ensuring that the machine can travel straight. •

Travel, Boom Raise 1. When performing combined operation of boom raise and travel, pilot pressure shifts travel (right) spool (3), travel (left) spool (2), boom 1 spool (7), and boom 2 spool (9). 2. At the same time, the travel (right) pilot pressure shifts the flow combiner valve control spool in the signal control valve. Therefore, primary pilot pressure (5) from the pilot pump is routed to flow combiner valve (4) through the signal control valve and shifts flow combiner valve (4). 3. Pressure oil from pump 1 (11) flows through travel (right) spool (3) and activates travel motor (right) (6). 4. At the same time, pressure oil from pump 1 (11) flows to travel (left) spool (2) through flow combiner valve (4) and activates travel motor (left) (1). 5. Pressure oil from pump 2 (10) flows to boom cylinder (8) through boom 2 spool (9) and raises the boom. 6. Pressure oil from pump 2 (10) is used for the boom. Pressure oil from pump 1 (11) is equally supplied to the right and left travel motors, ensuring that the machine can travel straight.

NOTE As the travel (right) circuit is a tandem circuit, pressure oil from pump 1 (11) does not flow to boom 1 spool (7).

TOJBQ40-EN-00(07/02/2020)

T2-4-24

SECTION2 SYSTEM Group4 Hydraulic System 8

3 6

B A

78910-

Boom 1 Spool Boom Cylinder Boom 2 Spool Pump 2

TJAQ-02-04-010-1 ja 1234-

Travel Motor (Left) Travel (Left) Spool Travel (Right) Spool Flow Combiner Valve

TOJBQ40-EN-00(07/02/2020)

Primary Pilot Pressure from Pi lot Pump (From Flow Combin er Valve Control Spool) Travel Motor (Right)

T2-4-25

11-

Pump 1

SECTION2 SYSTEM Group4 Hydraulic System Swing Flow Rate Control Circuit Purpose: The swing flow rate control circuit restricts pressure oil flowing to the swing in order to supply more pressure oil when performing combined operation of swing and boom raise, or swing and arm roll-out. Consequently, the operating speed of the boom or arm is maintained. •

Swing, Arm Roll-Out 1. When performing combined operation of swing and arm roll-out, the pilot pressure shifts swing spool (8), arm 1 spool (11), and arm 2 spool (2). 2. At this time, MC activates the swing flow rate control solenoid valve (SI). (Refer to SYSTEM/Control System.) 3. Pressure oil from the pilot pump flows through the swing flow rate control solenoid valve (SI) and acts on selector valve (5) of the swing flow rate control solenoid valve. 4. Pressure oil from pump 2 (7) flows to poppet valve (4) of the swing flow rate control valve and arm 1 spool (11) through parallel circuit (3). 5. As pressure oil from selector valve (5) acts on the back pressure of poppet valve (4), pressure oil from pump 2 (7) is restricted by poppet valve (4). 6. Pressure oil from pump 1 (6) flows to arm cylinder (12) through neutral circuit (1) and arm 2 spool (2), and rolls-out the arm. 7. Pressure oil from pump 2 (7) flows preferentially to arm cylinder (12) through arm 1 spool (11). This increases the arm roll-out operating speed.

TOJBQ40-EN-00(07/02/2020)

T2-4-26

SECTION2 SYSTEM Group4 Hydraulic System

B A

11 12

8 7 1234-

Neutral Circuit (Pump 1) Arm 2 Spool Parallel Circuit (Pump 2) Swing Flow Rate Control Sole noid (Poppet Valve)

TOJBQ40-EN-00(07/02/2020)

5678-

Swing Flow Rate Control Sole noid (Selector Valve) Pump 1 Pump 2 Swing Spool

1011-

T2-4-27

6 Pilot Pressure from Swing Flow Rate Control Solenoid Valve (SI) Swing Motor Arm 1 Spool

12-

TJAQ-02-04-024-1 ja Arm Cylinder

SECTION2 SYSTEM Group4 Hydraulic System Arm Regenerative Cut Circuit Purpose: The arm regenerative cut circuit shifts the arm regenerative cut valve according to other operating conditions and working conditions when performing arm roll-in operation. Therefore, the arm regenerative cut circuit controls to become a correct operation according to the pump load. •

Arm Roll-In, Boom Raise 1. When performing combined operation of arm roll-in and boom raise, the pilot pressure shifts arm 1 spool (9), arm 2 spool (3), boom 1 spool (5), and boom 2 spool (6). 2. Pressure oil from pump 1 (8) flows to arm cylinder (10) through neutral circuit (1), parallel circuit (2), and arm 2 spool (3), and rolls in the arm. At the same time, pressure oil from pump 1 (8) flows through parallel circuit (2), flows to boom cylinder (4) through boom 1 spool (5), and raises the boom at the same time. 3. Pressure oil from pump 2 (7) flows through parallel circuit (12) and boom 2 spool (6), is combined with pressure oil from pump 1 (8), flows to boom cylinders (4), and raises the boom. At the same time, pressure oil from pump 2 (7) flows through arm 1 spool (9), is combined with pressure oil from pump 1 (8), flows to arm cylinder (10), and rolls in the arm. 4. At this time, MC activates the arm regenerative control solenoid valve (SI) according to the pump delivery pressure and other operating conditions. (Refer to SYSTEM/Control System.) 5. Pressure oil from the pilot pump flows through the arm regenerative control solenoid valve (SI) and shifts the arm regenerative cut valve (13). 6. When pump delivery pressure is low, arm regenerative cut valve (13) is closed, and returning oil from the arm cylinder (10) rod side is divided into two directions. One flows to the hydraulic oil tank through arm 1 spool (9). The other flows through check valve (11), is combined with pressure oil from pump 2 (7), flows to arm cylinder (10), and rolls in the arm. 7. When pump delivery pressure becomes high, arm regenerative cut valve (13) is shifted and all returning oil from the arm cylinder (10) rod side flows to the hydraulic oil tank through arm 1 spool (9) and arm regenerative cut valve (13). (Arm Regenerative Cut Circuit) 8. Therefore, the pressure at arm cylinder (10) rod side decreases and the digging force is improved.

TOJBQ40-EN-00(07/02/2020)

T2-4-28

SECTION2 SYSTEM Group4 Hydraulic System 4

B A

2 10

9 11 12

13 14

7 1234-

Neutral Circuit (Pump 1) Parallel Circuit (Pump 1) Arm 2 Spool Boom Cylinder

TOJBQ40-EN-00(07/02/2020)

5678-

Boom 1 Spool Boom 2 Spool Pump 2 Pump 1

9101112-

T2-4-29

Arm 1 Spool Arm Cylinder Check Valve Parallel Circuit (Pump 2)

1314-

TJAQ-02-04-011-1 ja Arm Regenerative Cut Valve Pilot Pressure from Arm Re generative Control Solenoid Valve (SI)

SECTION2 SYSTEM Group4 Hydraulic System Arm 1 Flow Rate Control Circuit Purpose: The arm 1 flow rate control circuit shifts the arm 1 flow rate control valve when combined operation of swing and arm roll-in is performed. This increases the flow rate to the swing spool, increasing the swing speed. •

Swing, Arm Roll-In 1. When performing combined operation of swing and arm roll-in, the pilot pressure shifts swing spool (1), arm 1 spool (10), and arm 2 spool (5). 2. At this time, pilot pressure (12) from the signal control valve shifts selector valve (2) of the arm 1 flow rate control valve. 3. Pressure oil from pump 1 (8) flows to arm cylinder (6) through neutral circuit (4), parallel circuit (13), and arm 2 spool (5), and rolls in the arm. 4. Pressure oil from pump 2 (7) flows to poppet valve (3) of the arm 1 flow rate control valve and swing spool (1) through parallel circuit (11). 5. As the pressure oil from selector valve (2) acts on the back pressure of poppet valve (3), pressure oil from pump 2 (7) is restricted by poppet valve (3). 6. Consequently, pressure oil from pump 2 (7) preferentially flows to swing motor (9) through swing spool (1). This increases swing motor (9) operating speed.

TOJBQ40-EN-00(07/02/2020)

T2-4-30

SECTION2 SYSTEM Group4 Hydraulic System

B A

10 6 4

3 2 9 12

11 123-

Swing Spool Arm 1 Flow Rate Control Valve (Selector Valve) Arm 1 Flow Rate Control Valve (Poppet Valve)

TOJBQ40-EN-00(07/02/2020)

45678-

7 Neutral Circuit (Pump 1) Arm 2 Spool Arm Cylinder Pump 2 Pump 1

9101112-

T2-4-31

8 Swing Motor Arm 1 Spool Parallel Circuit (Pump 2) Pilot Pressure from Signal Control Valve

5 13-

TJAQ-02-04-012-1 ja Parallel Circuit (Pump 2)

SECTION2 SYSTEM Group4 Hydraulic System Arm 2 Flow Rate Control Circuit Purpose: When arm roll-in or arm roll-out single operation is performed, the arm 2 flow rate control circuit increases pressure oil flowing to arm 2 and delivers more pressure oil to the arm. This increases the arm operating speed. •

Arm Roll-In 1. When performing arm roll-in single operation, the pilot pressure shifts the arm 1 spool (1) and arm 2 spool (5). 2. At this time, MC activates the arm 2 flow rate control solenoid valve (SG). (Refer to SYSTEM/Control System.) 3. Pressure oil from the pilot pump flows through arm 2 flow rate control solenoid valve (SG) and shifts selector valve (2) of the arm 2 flow rate control valve. 4. Pressure oil from pump 2 (7) flows to arm cylinder (6) through neutral circuit (4), parallel circuit (11), and arm 1 spool (1), and rolls in the arm. 5. Pressure oil from pump 1 (8) flows to poppet valve (3) of the arm 2 flow rate control valve through parallel circuit (9). 6. The back pressure of poppet valve (3) shifts selector valve (2) of the arm 2 flow rate control valve. As a result, poppet valve (3) of the arm 2 flow rate control valve opens. 7. As a result, pressure oil from pump 1 (8) flows to arm cylinder (6), increasing the arm operation speed.

TOJBQ40-EN-00(07/02/2020)

T2-4-32

SECTION2 SYSTEM Group4 Hydraulic System

B A

6 9 2 3 1 10

8 TJAQ-02-04-013-1 ja

123-

Arm 1 Spool Arm 2 Flow Rate Control Valve (Selector Valve) Arm 2 Flow Rate Control Valve (Poppet Valve)

TOJBQ40-EN-00(07/02/2020)

45678-

Neutral Circuit (Pump 2) Arm 2 Spool Arm Cylinder Pump 2 Pump 1

910-

11-

T2-4-33

Parallel Circuit (Pump 1) Pilot Pressure from Arm 2 Flow Rate Control Solenoid Valve (SG) Parallel Circuit (Pump 2)

SECTION2 SYSTEM Group4 Hydraulic System Bucket Regenerative Cut Circuit Purpose: When the load is high at bucket roll-in operation, the bucket regeneration cut circuit flows back pressure oil at the bucket cylinder (3) rod side to hydraulic oil tank (5) without regeneration for the bottom side. Therefore, the pressure at bucket cylinder (3) rod side decreases and the digging force is improved. •

Regeneration Cut (Pump 1 (4) delivery pressure: High) 1. When the load becomes heavy at bucket roll-in operation, the bucket regeneration cut valve (1) is shifted by pressure oil from pump 1 (4). 2. Returning oil from the cylinder rod side flows to hydraulic oil tank (5) through bucket spool (2) and bucket regeneration cut valve (1). 3. The pressure at bucket cylinder (3) rod side decreases and the digging force is improved.

•

Regeneration (Pump 1 (4) delivery pressure: Low) 1. Pressure oil from pump 1 (4) acts on the bucket regeneration cut valve (1). 2. When the load is light at bucket roll-in operation, the bucket regeneration cut valve (1) is not shifted. 3. As returning oil from the cylinder rod side is restricted by the bucket regeneration cut valve (1), the pressure at the cylinder rod side is higher than the pressure at the cylinder bottom side. 4. Pressure oil from the cylinder rod side pushes to open the check valve in bucket spool (2) and flows to the cylinder bottom side. 5. The regeneration is done like this and the cylinder speed increases.

TOJBQ40-EN-00(07/02/2020)

T2-4-34

SECTION2 SYSTEM Group4 Hydraulic System

B A

4 TJAQ-02-04-014-1 ja 1-

Bucket Regeneration Cut Valve

TOJBQ40-EN-00(07/02/2020)

23-

Bucket Spool Bucket Cylinder

45-

T2-4-35

Pump 1 Hydraulic Oil Tank

SECTION2 SYSTEM Group4 Hydraulic System Boom Lower Meter-In Cut Control Purpose: When performing the boom lower operation with the front attachment above the ground, the boom lower meter-in cut control stops pressure oil which flows to boom cylinder from the pump. The boom falls due to the own weight by the boom regenerative circuit and pressure oil from the pump is used for other actuators. Therefore, other actuators are preferentially operated. The meter-in cut control is deactivated with the track raised off the ground. Therefore, the boom is given priority to operate and the jack-up force increases.

NOTE As an example, the combined operation of boom lower and arm roll-out is explained here.

Boom Cylinder Bottom Pressure: High (With the Front Attachment above the Ground) 1. When performing combined operation of boom lower and arm roll-out, the arm roll-out pilot pressure shifts arm 1 spool (9), arm 2 spool (1), boom 1 spool (4), and boom 2 spool (5). 2. When boom lower operation is done, boom lower meter-in cut valve (2) is shifted by the boom cylinder (3) bottom pressure. 3. Boom lower pilot pressure (10) shifts boom lower meter-in cut valve (2). As a result, pressure oil from pump 1 (8) stops flowing to pump 1 spool (4). 4. As a result of the boom weight, pressure oil in the boom cylinder (3) bottom side combines with the flow of pressure pol from boom 2 spool (5) and returns to the hydraulic oil tank. 5. As all pressure oil from pump 1 (8) and pressure oil from pump 2 (7) are used for arm cylinder (6), arm roll-out speed increases.

NOTE The illustration shows during combined operation of boom lower and arm roll-out.

TOJBQ40-EN-00(07/02/2020)

T2-4-36

SECTION2 SYSTEM Group4 Hydraulic System 3

B A

6 2

7 12-

Arm 2 Spool Boom Lower Meter-In Cut Valve

TOJBQ40-EN-00(07/02/2020)

345-

Boom Cylinder Boom 1 Spool Boom 2 Spool

678-

T2-4-37

8 Arm Cylinder Pump 2 Pump 1

1 910-

TJAQ-02-04-015-1 ja Arm 1 Spool Boom Lower Pilot Pressure

SECTION2 SYSTEM Group4 Hydraulic System Boom Cylinder Bottom Pressure: Low (With Track Raised off the Ground) 1. When the boom lower operation is done with the bucket set on the ground, the boom cylinder (3) bottom pressure becomes low and boom lower meter-in cut valve (1) is not shifted. 2. As boom lower pilot pressure (7) does not act on selector valve (8) of boom flow rate control valve, poppet valve (9) of boom flow rate control valve opens. 3. Pressure oil from pump 1 (6) flows through boom 1 spool (2). Pressure oil from boom cylinder (3) bottom side is combined with pressure oil from boom 2 spool (4) and returns to the hydraulic oil tank.

TOJBQ40-EN-00(07/02/2020)

T2-4-38

SECTION2 SYSTEM Group4 Hydraulic System 3

8 9 B A

4 1

6 12-

Boom Lower Meter-In Cut Valve Boom 1 Spool

TOJBQ40-EN-00(07/02/2020)

345-

Boom Cylinder Boom 2 Spool Pump 2

67-

Pump 1 Boom Lower Pilot Pressure

89-

T2-4-39

TJAQ-02-04-016-1 ja Boom Flow Rate Control Valve (Selector Valve) Boom Flow Rate Control Valve (Poppet)

SECTION2 SYSTEM Group4 Hydraulic System Radiator and Oil Cooler Fan Reverse Rotation Control Circuit 1. Pressure oil from radiator fan pump (1) is routed to radiator fan motor (4) through radiator fan reverse rotation spool (3) of radiator fan valve (2). 2. Pressure oil from oil cooler fan pump (11) is routed to oil cooler fan motor (10) through oil cooler fan reverse rotation spool (8). 3. MC (12) activates fan reverse rotation control solenoid valve 1 (6) and fan reverse rotation control solenoid valve 2 (7) according to the signal from fan reverse rotation switch (13). 4. When fan reverse rotation control solenoid valve 1 (6) and fan reverse rotation control solenoid valve 2 (7) are activated, pressure oil from pilot pump (5) and oil cooler fan pump (11) shifts radiator fan reverse rotation spool (3) and oil cooler fan reverse rotation spool (8). 5. The delivery ports of radiator fan valve (2) and oil cooler fan valve (9) are shifted and radiator fan motor (4) and oil cooler fan motor (10) rotate in the reverse direction. (Refer to SYSTEM/Control System.) 6. Therefore, the cores of the radiator and the oil cooler are cleaned. 13 12 MC

4 10 2 9

8 3

11 1234-

Radiator Fan Pump Radiator Fan Valve Radiator Fan Reverse Rotation Spool Radiator Fan Motor

TOJBQ40-EN-00(07/02/2020)

567-

Pilot Pump Fan Reverse Rotation Control Solenoid Valve 1 Fan Reverse Rotation Control Solenoid Valve 2

891011-

T2-4-40

Oil Cooler Fan Reverse Rota tion Spool Oil Cooler Fan Valve Oil Cooler Fan Motor Oil Cooler Fan Pump

1213-

TJBQ-02-04-005-1 ja MC Fan Reverse Rotation Switch

SECTION2 SYSTEM Group5 Electrical System Outline of Electrical System The electrical circuit is broadly divided into the main circuit, monitor circuit, accessory circuit, and control circuit. •

The main circuit consists of the engine and the accessory related circuits.

•

The monitor circuit displays the machine operating conditions. The monitor circuit consists of the monitor controller, monitor, relays, and switches.

•

The accessory circuit controls the various lights, the wiper, and the washer. The accessory circuit consists of the monitor controller, relays, and switches.

•

The control circuit controls the engine, pump, and valve. The control circuit consists of the actuators such as solenoid valves, MC, ECM, sensors, and switches. (Refer to SYSTEM/Control System.)

Main Circuit of Electrical System The major functions and circuits in the main circuit are as follows. •

The electric power circuit supplies electrical power to all electrical systems in the machine. {Key Switch, Battery, Fuses (Fuse Box, Fusible Link)}

•

The CAN circuit performs communication between each controller.

•

The accessory related circuit is operated when the key switch is in the ACC position.

•

The starting circuit starts the engine. (Key Switch, Starter, Starter Relay)

•

The charging circuit supplies electric power to the batteries and charges them. {Alternator, (Regulator)}

•

The surge voltage prevention circuit prevents the occurrence of serge voltage developed when stopping the engine. (Load Dump Relay)

•

The pilot shut-off circuit controls the pilot shut-off solenoid valve according to the pilot shut-off lever position. The pilot shut-off solenoid valve controls the pilot pressure oil that flows from the pilot pump to the pilot valve. (Pilot Shut-off Solenoid Valve, Pilot Shut-Off Lever)

•

The auto shut-down circuit/automatic engine stop circuit at low temperature automatically stops the engine when the specified conditions exist. (MC, ACC Cut Relay, Key Switch ON Cut Relay)

•

The engine stop circuit (key switch: OFF) stops the engine by using ECM. (MC, ECM)

Electric Power Circuit (Key Switch: OFF) The battery (1) negative terminal is grounded to the body. The circuit from the battery (1) positive terminal is connected as shown below when key switch (5) is in the OFF position.

TOJBQ40-EN-00(07/02/2020)

T2-5-1

SECTION2 SYSTEM Group5 Electrical System Battery (1) Fusible Link (2)

Battery Key Switch (5) Terminal B Disconnect Load Dump Relay (4) Switch (3) Fuel Filling Device (25) Fuse Box 1 (6)

Terminal #8

ECM Main Relay (Power) (21)

Terminal #9

Monitor Controller (Backup Power) (12) Switch Panel (13) Cab Light (14) Radio (Backup Power) (15) Security Horn (Power) (16) Security Horn Relay (Power) (17) GSM (Power) (18)

Fuse Box 2 (7)

TOJBQ40-EN-00(07/02/2020)

Terminal #10

MC (Power) (11)

Terminal #19

Horn Relay (Power) (22)

Terminal #20

Option (26)

Terminal #34

DCU (Power) (23)

Terminal #36

GSM (24)

T2-5-2

Battery Disconnect Switch Indicator (27)

SECTION2 SYSTEM Group5 Electrical System B

KEY̲SW

H OFF ACC ON START

L R11 1 3 ACC̲CUT

3 R

R AVX

8f 2f 2f

W AV WB AEX B

5W 38+

26+ 2 YR 36+ 2 RW AVS

5 W 32+

21+

30+ 40+

28+ 5 W 24+ 35+ 34+ 25+ 2 YB

WR G L 7+ 1.25 14+ 3 18+ 3

4+ 5 W 8+ 3 R

16+ 2 YB

1+ 5 W

19+ 3 R 13+ 2 G

15+ 3 W

11+ 5 W

R R

2 YB

FUSE̲BOX2

2 2 2 5 4

2 YB

16 12 11 3 15 8 2 1 19 13

8 19

10A

5A 5A 10A 5A 20A 3926273623-

10A 22-

10A

10A 10A 3221-

38-

5A 31-

37-

10A 33-

40-

10A 10A 15A 20A 5A 10A 10A 10A 28243534252930-

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

R1 2 5 4 LOAD DUMP R4 STARTER CUT

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

1 3

L WR 1 3

DIODE3 A AVSS

4 9 10 17 6 20 5 7 14 18

9 10 20

24 WL GLOW̲PLUG RELAY

4 2

3 1

5 BY AEX 1 ENG̲4

GLOW̲PLUG

W W

C B S E

FUEL̲FILLING/P

AEX AEX

2 4

W AV

1 3

R AV

1.5

FLOAT̲SW

FORK̲10

0.85 2

1.5 1.5 10A

W SF-3 2 B

B S

1 2

BOX;CONTROL

A E

STARTER

B B

1.5

BATTERY̲RELAY

1.5 1.5

5 R 2 W B S 1

B 1 B 2

AVSS AVXS

STOP

3 R 2 W 5 W

AVXS AVXS AEX AEX

60 -

BATTERY

1 59 2

W W W LY

1.5 1.5

AVXS

5 5 0.85 0.85

60 R -

1 2

R W W

2 5 4

2 G

3 R 3 B

AVXS

DIODE1 A K 2 W AVSS

3 RW

5 W

2 B

3 R

2 RW

AVSS

61 13

AVXS

R5 KEY̲ON̲CUT

DIODE5 2 B AVSS A K

DISCONNECT̲SW

1 3

2 5 4

AEX

B R

RW LY

START

L 3 L

3 W

5 1 4 3

3f W 3f W 3f L 2f WR

W5 1 4 3

OFF

B G1 G2 ACC M ST

STARTER̲RELAY

25 ACG B 8 R 2 0.85 L 3 0.85

W W LY

SF-3 AEX AEX

26 27

REGULATOR

ALTERNATOR

12 13 14 15 16 17 18 123456-

Battery Fusible Link Battery Disconnect Switch Load Dump Relay Key Switch Fuse Box 1

711121314-

Fuse Box 2 MC (Power) Monitor Controller (Backup Power) Switch Panel Cab Light

151617182122-

Radio (Backup Power) Security Horn (Power) Security Horn Relay (Power) GSM (Power) ECM Main Relay (Power) Horn Relay (Power)

2324252627-

TJAQ-02-05-001-1 ja DCU (Power) GSM Fuel Filling Device Option Battery Disconnect Switch In dicator

TOJBQ40-EN-00(07/02/2020)

T2-5-3

SECTION2 SYSTEM Group5 Electrical System 2 4 3 17

6 VGS

18 9

17 19 DCU

26 17

17 1

7 ECM

24 17

11 MPDr.

17 5 16

8 MC

17 27

22 17 17

25 PLCU

30 SW-BOX

17 29

14 28

1234567-

Power- CAN CAN-H (High) CAN-L (Low) CAN Bus Body- CAN VGS Controller (Variable Tur bo Controller) ECM (Engine Controller)

89101112131415-

MC (Main Controller) Communication Controller Monitor Controller MPDr. Aerial Angle Controller Radio Controller Air Conditioner Controller Monitor Control Unit

1617181920212223-

Information Control Unit Termination Resistor (120 Ω) ISO-CAN DCU Local-CAN DEF Sensor Unit PL-CAN Upstream NOx Sensor

24252627282930-

TDFY-02-01-001-1 ja Downstream NOx Sensor PLCU (Option) IF-CAN OPT-CAN Engine Oil Monitoring Sensor Hydraulic Oil Monitoring Sen sor Switch Box Controller

Accessory Circuit (Key Switch: ACC) 1. When key switch (2) is set to the ACC position, terminal B is connected to the terminal ACC in key switch (2). 2. The circuit from the terminal ACC in key switch (2) is connected as shown below and makes each accessory operation possible.

TOJBQ40-EN-00(07/02/2020)

T2-5-4

SECTION2 SYSTEM Group5 Electrical System Key Switch (2) Terminal ACC

ACC Cut Relay (3)

Fuse Box 1 (4)

Terminal Radio (6) #13 Terminal Monitor Controller (5) #14 Terminal Auxiliary (7) #15

B G1 G2 ACC M ST

B ACC KEY̲SW

H OFF ACC ON START

3 5 1 4 3

L 3 L

3 W

R11 1 3 ACC̲CUT

ACC

3f W 3f W 3f L 2f WR

W5 1 4 3

Fuse Box 1 (4)

3 R

5 R 2 W B S 1

A E

8f 2f 2f

W AV WB AEX B

YG WR G L 7+ 1.25 14+ 3 18+ 3

4+ 5 W 8+ 3 R

16+ 2 YB

1+ 5 W

19+ 3 R 13+ 2 G

15+ 3 W

11+ 5 W

R1 2 5 4 LOAD DUMP R4 STARTER CUT

16 12 11 3 15 8 2 1 19 13

4 9 10 17 6 20 5 7 14 18

WL 2 GLOW̲PLUG RELAY

4 2

5 BY AEX 1 ENG̲4

GLOW̲PLUG

W W

B S E

3 1

AEX AEX

2 4

1 3

DIODE5 2 B AVSS A K

R AVX

1 3

2 YB

W AV

R AV

FORK̲10

B S

W SF-3 2 B

STARTER

2 5 4

BATTERY̲RELAY

1 3

DIODE3 A AVSS

2 5 4

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

2 B

AVSS

W W W LY

60 -

BATTERY

5 5 0.85 0.85

60 R +

AVXS AVXS AEX AEX

AVSS AVXS

3 R 2 W 5 W

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

1 59 2

R R

AVXS

2 G

2 2

R W W

2 5 4

2 RW

DIODE1 A K 2 W AVSS

3 R

61 13

AVXS

L WR

AEX

0.85 2

DISCONNECT̲SW

RW LY

R5 KEY̲ON̲CUT

3 RW

1 3

STARTER̲RELAY

ACG E

B 8 R 2 0.85 L 3 0.85

W W LY

SF-3 AEX AEX

REGULATOR

ALTERNATOR

TDFY-02-05-002-1 ja 12-

Battery Key Switch

34-

ACC Cut Relay Fuse Box 1

56-

Monitor Controller Radio

Auxiliary

Starting Circuit (Key Switch: START) 1. When key switch (7) is set to the START position, terminal B is connected to the terminals M and ST in key switch (7). 2. Current from the terminal M excites battery relay (4) through key switch ON cut relay (9). Current from battery (1) is routed to terminal B of starter (2) and terminal B of starter relay (3) through battery relay (4). 3. Current from terminal M of key switch (7) flows as follows as a signal indicating that key switch (7) is in the ON position or START position. Key Switch (7) Terminal M

Fuse #18

Monitor Controller (11)

Key Switch ON Cut Relay (9)

Fuse #17

ECM (13) DCU (20) MC (12)

4. When ECM (13) receives this signal, ECM (15) turns ON ECM main relay (14). 5. Current from battery (1) flows to ECM (13) through fuse #8 and ECM main relay (14), and the ECM (13) main power is turned ON. TOJBQ40-EN-00(07/02/2020)

T2-5-5

SECTION2 SYSTEM Group5 Electrical System 6. At the same time, current from fuse #8 flows through ECM main relay (14) and fuse #24 to DEF sensor unit (19), upstream NOx sensor (15), and downstream NOx sensor (16). 7. ECM (13) controls the condition of the engine to be able to start. 8. Current from the terminal ST flows to terminal S in starter relay (3) through starter cut relay (5). 9. Current flows to the coil in starter relay (3) and starter relay (3) is turned ON. 10. Current flows to terminal S in starter (2) from terminal C in starter relay (3). 11. The relay in starter (2) is turned ON so that the starter motor rotates. 7

B M

START 1

24 18 10

S C B S

12 MC

20 DCU

15 12345-

Battery Starter Starter Relay Battery Relay Starter Cut Relay

TOJBQ40-EN-00(07/02/2020)

13 ECM

16 19 6791011-

Fuse Box 1 Key Switch Key Switch ON Cut Relay Fuse Box 2 Monitor Controller

1213141516-

T2-5-6

MC ECM ECM Main Relay Upstream NOx Sensor Downstream NOx Sensor

1920-

TDFY-02-05-003-1 ja DEF Sensor Unit DCU

SECTION2 SYSTEM Group5 Electrical System Charging Circuit (Key Switch: ON) 1. After the engine starts and key switch (3) is released key switch (3) is returned to the ON position. 2. Terminal B is connected to the terminals ACC and M in key switch (3) with key switch (3) set in the ON position. 3. Alternator (5) starts generating electricity with the engine running. Current from terminal B in alternator (5) flows to batteries (1) through battery relay (2) and charges batteries (1). 4. Current from terminal L in alternator (5) flows to monitor controller (4). 5. Monitor controller (4) detects the alternator (5) generating electricity according to the electric source from alternator (5) and deletes the alternator alarm on the monitor. ACC

B G1 G2 ACC M ST

L 3 L

3 W

R11 1 3 ACC̲CUT

5 1 4 3

3f W 3f W 3f L 2f WR

W5 1 4 3

KEY̲SW

H OFF ACC ON START

3 R

5 R 2 W B S 1

A E

8f 2f 2f

W AV WB AEX B

YG WR G L 7+ 1.25 14+ 3 18+ 3

16+ 2 YB

4+ 5 W 8+ 3 R

19+ 3 R 13+ 2 G

15+ 3 W

1+ 5 W

11+ 5 W

16 12 11 3 15 8 2 1 19 13

4 9 10 17 6 20 5 7 14 18

W AV

2 GLOW̲PLUG RELAY

4 2

5 BY AEX 1 ENG̲4

GLOW̲PLUG

W W

B S E

3 1

AEX AEX

2 4

2 5 4

R1 2 5 4 LOAD DUMP R4 STARTER CUT

DIODE5 2 B AVSS A K

R AVX

1 3

R AV

FORK̲10

B S

W SF-3 2 B

STARTER

1 3

BATTERY̲RELAY

2 YB

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

DIODE3 A AVSS

2 5 4

1 3

2 B

AVSS

BATTERY

W W W LY

5 5 0.85 0.85

AVXS AVXS AEX AEX

60 R

AVSS AVXS

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

3 R 2 W 5 W

R R

1 59 2

2 2

AVXS

2 G

DIODE1 A K 2 W AVSS

R W W

2 5 4

2 RW

3 R

L WR

AVXS

R5 KEY̲ON̲CUT

DISCONNECT̲SW

3 RW

0.85 2

1 3

STARTER̲RELAY

B ACG B 8 R 2 0.85 L 3 0.85

W W LY

SF-3 AEX AEX

L REGULATOR

ALTERNATOR

4 5 TDFY-02-05-004-1 ja

12-

Battery Battery Relay

TOJBQ40-EN-00(07/02/2020)

34-

Key Switch Monitor Controller

T2-5-7

Alternator

SECTION2 SYSTEM Group5 Electrical System Alternator Operation ● Alternator (5) consists of field coil FC, stator coil SC, and diodes D. ● Regulator (6) consists of transistors T1, T2, Zener diode ZD, and resistances R1 to R6, RF. ● Terminal M (4) in the key switch is connected to base B of transistor T1 through R, RF, (R), and R1. ● When battery relay (2) is in the ON position, the battery (1) voltage is applied to base B of transistor T1 in regulator (6), and collector C is connected to emitter E. Therefore, field coil FC is grounded through transistor T1. ● At the beginning, no current is flowing to field coil FC. When the rotor starts rotating, the alternate current is generated in stator coil SC due to the rotor remnant magnetism. ● When current flows to field coil FC, the rotor is further magnetized and the generating voltage increases. Then, current flowing to field coil FC increases. Therefore, the generating voltage increases further and batteries (1) start charging. 3

2 (R)

TDAA-02-05-004-1 ja 12-

Battery Battery Relay

TOJBQ40-EN-00(07/02/2020)

34-

To Key Switch Terminal B From Key Switch Terminal M

56-

T2-5-8

Alternator Regulator

SECTION2 SYSTEM Group5 Electrical System Regulator Operation ● When the generating voltage increases more than the set voltage of Zener diode ZD, current flows to base B of transistor T2 and collector C is connected to emitter E. ● Current flowing to base B of transistor T1 disappears due to the transistor T2 operation, and transistor T1 is turned OFF. ● No current flows to filed coil FC and the generating voltage at stator coil SC decreases. ● When the generating voltage decreases lower than the set voltage of Zener diode ZD, transistor T2 is turned OFF and transistor T1 is turned ON again. ● Current flows to field coil FC and the generating voltage at stator coil SC increases. The above operation is repeated and the alternator (5) generating voltage is kept constant. 3

TDAA-02-05-003-1 ja 12-

Battery Battery Relay

34-

To Key Switch Terminal B From Key Switch Terminal M

56-

Alternator Regulator

Surge Voltage Prevention Circuit 1. When the engine is stopped (key switch (4): OFF), current from terminal M in key switch (4) disappears and battery relay (2) is turned OFF. 2. The engine continues to rotate due to the inertia force just after key switch (4) is turned OFF and alternator (5) continues to generate electricity. 3. As the generating current cannot flow to battery (1), surge voltage arises in the circuit and failures of the electronic components, such as controller, possibly cause. In order to prevent the occurrence of surge voltage, the surge voltage prevention circuit is provided. 4. When alternator (5) is generating electricity, the generating current from alternator (5) terminal L flows to terminal #A23 of monitor controller (6). Monitor controller (6) connects terminal #B30 to the ground. 5. Therefore, current flows to the exciting circuit in load dump relay (3) and load dump relay (3) is turned ON. 6. Consequently, even if key switch (4) is set to the OFF position with the engine running, current from battery (1) continues to excite battery relay (2) through load dump relay (3).

TOJBQ40-EN-00(07/02/2020)

T2-5-9

SECTION2 SYSTEM Group5 Electrical System 7. In addition, when a specified time has passed since alternator (5) stops generating electricity, monitor controller (6) disconnects terminal #B30 from the ground. Therefore, battery relay (2) is turned OFF. M B G1 G2 ACC M ST

4 KEY̲SW

H OFF ACC ON START

L 3 L

3 W

R11 1 3 ACC̲CUT

5 1 4 3

3f W 3f W 3f L 2f WR

W5 1 4 3

OFF

3 R

5 R 2 W B S 1

1 3

2 5 4

A E

8f 2f 2f

W AV WB AEX B

YG WR G L 7+ 1.25 14+ 3 18+ 3

16+ 2 YB

4+ 5 W 8+ 3 R

19+ 3 R 13+ 2 G

15+ 3 W

1+ 5 W

11+ 5 W

16 12 11 3 15 8 2 1 19 13

4 9 10 17 6 20 5 7 14 18

W AV

2 GLOW̲PLUG RELAY

4 2

5 BY AEX 1 ENG̲4

GLOW̲PLUG

W W

B S E

3 1

AEX AEX

2 4

R1 2 5 4 LOAD DUMP R4 STARTER CUT

DIODE5 2 B AVSS A K

R AVX

1 3

R AV

FORK̲10

B S

W SF-3 2 B

STARTER

BATTERY̲RELAY

2 YB

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

DIODE3 A AVSS

2 5 4

1 3

2 B

AVSS

BATTERY

W W W LY

5 5 0.85 0.85

AVXS AVXS AEX AEX

60 R

L WR

AVSS AVXS

3 R 2 W 5 W

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

1 59 2

R R

AVXS

2 G

DIODE1 A K 2 W AVSS

R W W

2 5 4

2 RW

2 2

3 R

0.85 2

AVXS

R5 KEY̲ON̲CUT

DISCONNECT̲SW

3 RW

1 3

STARTER̲RELAY

ACG B 8 R 2 0.85 L 3 0.85

W W LY

SF-3 AEX AEX

A23

B30

REGULATOR

ALTERNATOR

6 5 TDFY-02-05-005-1 ja

12-

Battery Battery Relay

34-

Load Dump Relay Key Switch

56-

Alternator Monitor Controller

Pilot Shut-Off Circuit (Key Switch: ON) 1. When the pilot shut-off lever is set to the UNLOCK position, pilot shut-off switch (5) is turned OFF. 2. Current from the terminal M in key switch (6) flows to fuse #25. 3. Current from fuse #25 flows through pilot shut-off switch (5) and pilot shut-off relay (2) to the pilot shut-off solenoid valve (3). 4. Therefore, pilot shut-off solenoid valve (3) is turned ON and pressure oil from the pilot pump is supplied to the pilot valve. • Neutral Engine Start Circuit 1. When the pilot shut-off lever is set to the UNLOCK position, the coil of starter cut relay (4) is connected to the ground. 2. Therefore, starter cut relay (4) is excited. 3. When starter cut relay (4) is excited, the circuit between terminal ST in key switch (6) and terminal S of starter relay (10) is disconnected. 4. Therefore, when the pilot shut-off lever is in the UNLOCK position, even if key switch (6) is set to the START position, the starter does not rotate and the engine does not start.

TOJBQ40-EN-00(07/02/2020)

T2-5-10

SECTION2 SYSTEM Group5 Electrical System NOTE When the pilot shut-off lever is set to the UNLOCK position, current stops flowing to terminal #F18 of MC (9). Therefore, MC (9) recognizes that the pilot shut-off lever is in the UNLOCK position. M

5 1 4 3

L 3 L

3 W

L R11 1 3 ACC̲CUT

3 R

8f 2f 2f

W AV WB AEX B

38+ 5

22+

27+ 2 YR 36+ 2 RW

W 32+ 5

22- 10A

5 W

28+ 24+

34+ 3 R 25+ 2 YB

WR G L 7+ 1.25 14+ 3 18+ 3

FUSE̲BOX2

DCDC 12̲OUT IGNI 2 GND3 GND6

12V(SW) 24V̲IN

2 B 2 B 2 B

4+ 5 W 8+ 3 R

16+ 2 YB

1+ 5 W

19+ 3 R 13+ 2 G

15+ 3 W

11+ 5 W

R R

Y 2 12V̲UNIT

39- 5A 26- 5A 27- 10A 36- 5A 23- 20A

37- 10A

USB

38- 10A

31- 5A

4 9 10 17 6 20 5 7 14 18

33- 10A

16 12 11 3 15 8 2 1 19 13

282435342529-

10A 10A 20A 20A 5A 10A

R1 2 5 4 LOAD DUMP

R4 STARTER CUT

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

2 5 4

SOCKET(12V) 1.25 YR

2 1.25

12V̲SOCKET YR

5 YR

1 24V̲IN USB

5 BY AEX 1 ENG̲4

GLOW̲PLUG

5 RB

Br 2

6 B

7 V

3 4

PILOT̲SHUT-OFF̲SW

1 2 PILOT̲SHUT-OFF VALVE

AVS R AVS B CAB

0.85

RL RL

0.85

SF-3 AEX AEX

B19

1 2

4 1

L B

LINK

ENG̲STOP̲SW 3 NORMAL G STOP Y 5 NORMAL R 6 STOP W 2

G L

A17 A18

3 GyR

W W LY

B 8 R 2 0.85 L 3 0.85

B21

CASE̲EARTH

ACG

G BR G

WL 2

GLOW̲PLUG RELAY

4 2

3 GND

R RL L RB

FUEL̲PUMP

STARTER̲RELAY

4 5

W W

C B S E

3 1

AEX AEX

2 4

1 3

2 5 4

DIODE5 2 B AVSS A K

R AVX

A23

24 4 G SF-3 5

6 B SF-3

1 3

W AV

R AV

FORK̲10

B S

W SF-3 2 B

STARTER

1 3 R12 LOCK

VR 58

A E

1 3

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

5 R 2 W BATTERY̲RELAY

2 YB

B S 1

2 B

AVSS

60 -

BATTERY

W W W LY

5 5 0.85 0.85

60 R -

AVXS AVXS AEX AEX

DIODE3 A AVSS

R5 KEY̲ON̲CUT

2 5 4

2 G

AVSS AVXS

2 2

AVXS

3 R 2 W 5 W

5 W

1 59 2

L WR

AVXS

R W W 3 RW

AVXS

AEX

0.85 2

3 R

R R

DISCONNECT̲SW

2 RW

DIODE1 A K 2 W AVSS

1 3

2 5 4

61 13

RW LY

32- 10A 21- 10A

3f W 3f W 3f L 2f WR

START

KEY̲SW

H OFF ACC ON START

W5 1 4 3

B G1 G2 ACC M ST

RL 1 R3 SEC̲HORN 1 3 PG 2

REGULATOR

G L

SEC̲HORN

ALTERNATOR

A4 A3 D1 D9

GB B32

3 G

2 5 4

1 3

2 5 4

R2 ECU

D26 RB

V RW G L G L E30 E28 E23 E31

F18 D26

0.85 0.85 1.25 1.25 1.25

G L 52 53

E1 E2 D5 D6 D7 F25 C32

RB 14

GyR 26

L L R R R RB VR

F18

CAB/H̲4

4 AVS L

9 MC

G L V64 V81

AVSSCS AVSSCS

G L V60 V77

AVSS AVSS

RB AVSS V76

YW YW V40 V57

L AVSS L AVSS L AVSS

GyR AVSS V50

A B

15 16 13 14

123-

Battery Pilot Shut-Off Relay Pilot Shut-Off Solenoid Valve

45-

Starter Cut Relay Pilot Shut-Off Switch (Pilot Shut-Off Lever)

678-

Key Switch Fuse Box 2 Monitor Controller

0.75

V1 V3 V5

V91

1.25 1.25 1.25

BrY V74

G AVSSCS L AVSSCS

27 CAB/H̲2

VG 16

G AVSSCS L AVSSCS

910-

TDFY-02-05-006-1 ja MC Starter Relay

Auto Shut-Down Circuit/Automatic Engine Stop Circuit at Low Temperature 1. Current from the terminal M excites battery relay (2) through key switch ON cut relay (6) with key switch (3) set in the ON position. 2. Current from terminal M flows to the coils of ACC cut relay (5), key switch ON cut relay (6), and starter cut relay (10) through fuse #18. 3. When all following conditions exist, monitor controller (7) connects terminal #B5 to the ground inside. (Refer to SYSTEM/Control System.) TOJBQ40-EN-00(07/02/2020)

T2-5-11

SECTION2 SYSTEM Group5 Electrical System Condition for Auto Shut-Down: •

Pilot Shut-Off Lever: LOCK Position

•

Auto shut-down: ON

•

Overheat alarm: OFF

•

Coolant temperature: 60 to 100 °C

•

Manual regeneration switch: OFF

•

Abnormal communication of ECM or monitor controller: None

•

Overload alarm switch: OFF

•

Fan Reverse Rotation Switch: OFF

• Learning Switch: OFF Condition for Automatic Engine Stop at Low Temperature: •

Pilot Shut-Off Lever: LOCK position (60 minutes)

• Ambient temperature or intake-air temperature: -20 °C or less 4. Therefore, ACC cut relay (5) and key switch ON cut relay (6) are turned ON. 5. The current which indicates key switch (3) is in the ON position, stops flowing from fuse #17 to terminal #V76 of ECM (8). 6. At the same time, battery relay (2) is turned OFF at the same time. 7. Therefore, this is the same situation when key switch (3) is set to the OFF position. ECM (8) stops the fuel injection of the injector and stops the engine. 8. When the engine stops, ECM (8) turns OFF ECM main relay (9).

IMPORTANT After stopping the engine, the DEF pump continues to be operated for a specified time in order to return DEF from the hose to the DEF tank. Do not set the , battery disconnect switch to the OFF position while battery disconnect switch indicator is lighting.

NOTE When restarting the engine, return the key switch to the OFF or ACC position and then reset it to the START position.

TOJBQ40-EN-00(07/02/2020)

T2-5-12

SECTION2 SYSTEM Group5 Electrical System M

L 3 L

3 W

L R11 1 3 ACC̲CUT

3 R

8f 2f 2f

W AV WB AEX B

38+ 5

27+ 2 YR 36+ 2 RW

W 32+ 5

22+

32- 10A 21- 10A

28+ 24+

5 W

WR G L

DCDC 12̲OUT IGNI 2 GND3 GND6

12V(SW) 24V̲IN

2 B 2 B 2 B

4+ 5 W 8+ 3 R

1+ 5 W

19+ 3 R 13+ 2 G

11+ 5 W

R R

Y 2

12V̲UNIT

37- 10A

39- 5A 26- 5A 27- 10A 36- 5A 23- 20A USB

38- 10A

4 9 10 17 6 20 5 7 14 18

31- 5A

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

16 12 11 3 15 8 2 1 19 13

33- 10A

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

10A 10A 20A 20A 5A 10A

R1 2 5 4 LOAD DUMP

R4 STARTER CUT

SOCKET(12V) 1.25 YR

2 1.25

12V̲SOCKET

5 YR

1 24V̲IN

R RL L RB

USB

3 GND

GLOW̲PLUG

5 RB

Br 2

6 B

7 V

3 4

1 2 PILOT̲SHUT-OFF VALVE

STARTER̲RELAY

AVS R AVS B CAB

0.85

B19

G L

A17 A18

1 2

4 1

L B

LINK

ENG̲STOP̲SW 3 NORMAL G STOP Y 5 NORMAL R 6 STOP W 2

SF-3 AEX AEX

W W LY

GyR

B 8 R 2 0.85 L 3 0.85

B21

CASE̲EARTH

ACG E

PILOT̲SHUT-OFF̲SW

G BR G

WL 2

B SF-3 5 BY AEX 1 ENG̲4

FUSE̲BOX2

2 2 L WR 0.85 2 2 5 4

FUEL̲PUMP

GLOW̲PLUG RELAY

4 2

A23

4 5

W W

C B S E

3 1

2 5 4

24 4 G SF-3 5

AEX AEX

2 4

1 3

2 5 4

DIODE5 2 B AVSS A K

R AVX

1 3

W AV

R AV

FORK̲10

B S

W SF-3 2 B

STARTER M

1 3 R12 LOCK

VR 58

A E

R5 KEY̲ON̲CUT

1 3

5 R 2 W B S 1

BATTERY̲RELAY

2 B

AVSS

60 -

BATTERY

W W W LY

5 5 0.85 0.85

60 R -

AVXS AVXS AEX AEX

2 YB

15+ 3 W

AVSS AVXS

3 RW

2 5 4 2 G DIODE3 K A AVSS

R R

DISCONNECT̲SW

AVXS

34+ 3 R 25+ 2 YB

AVXS

3 R 2 W 5 W

282435342529-

5 W

1 59 2

2 RW

7+ 1.25 14+ 3 18+ 3

61 13

AVXS

16+ 2 YB

AEX

RW LY

R W W

3 R

2 4

DIODE1 A K 2 W AVSS

1 3

22- 10A

R 3f 6

5 1 4 3

3f W 3f W 3f L 2f WR

KEY̲SW

H OFF ACC ON START

W5 1 4 3

B G1 G2 ACC M ST

RL 1 R3 SEC̲HORN 1 3 PG 2

REGULATOR

G L

SEC̲HORN

ALTERNATOR 2 5 4

A4 A3 D1 D9

GB B32

3 G

9 1 3

2 5 4

R2 ECU

V RW G L G L E30 E28 E23 E31

F18 D26

0.85 0.85 1.25 1.25 1.25 E1 E2 D5 D6 D7 F25 C32

G L

G AVSSCS L AVSSCS

52 53

RB AVSS

AVSS AVSS

AVSSCS AVSSCS

G L

V76

V60 V77

V64 V81

CAB/H̲4

YW YW V40 V57

AVS

GyR AVSS V50

BrY V74

2 A B

15 16 13 14

8 ECM 123-

Battery Battery Relay Key Switch

456-

Fuse Box 1 ACC Cut Relay Key Switch ON Cut Relay

789-

0.75

V1 V3 V5

1.25 1.25 1.25

L AVSS L AVSS L AVSS

G AVSSCS L AVSSCS

16 YL V91

27 CAB/H̲2

GyR

L L R R R RB VR

V76

Monitor Controller ECM ECM Main Relay

10-

TDFY-02-05-007-1 ja Starter Cut Relay

Engine Stop Circuit 1. When key switch (1) is set from the ON position to OFF position, current from the terminal M in key switch (1) stops flowing to terminal #V76 of ECM (4). 2. ECM (4) stops the fuel injection of the injector and stops the engine. 3. When the engine stops, ECM (4) turns OFF ECM main relay (3). Then, ECM (4) is turned OFF.

TOJBQ40-EN-00(07/02/2020)

T2-5-13

SECTION2 SYSTEM Group5 Electrical System M

B G1 G2 ACC M ST

OFF

KEY̲SW

H OFF ACC ON START

L 3 L L

3 W

R11 1 3 ACC̲CUT

3 R

A E

R AVX W AV WB AEX B

38+ 5

22+

27+ 2 YR 36+ 2 RW

W 32+ 5

22- 10A

5 W

34+ 3 R 25+ 2 YB

28+ 24+

24V̲IN

Y 2

12V̲UNIT

39- 5A 26- 5A 27- 10A 36- 5A 23- 20A

37- 10A

USB

38- 10A

31- 5A

4 9 10 17 6 20 5 7 14 18

33- 10A

10A 10A 20A 20A 5A 10A 16 12 11 3 15 8 2 1 19 13

282435342529-

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

SOCKET(12V) 1.25 YR

2 1.25 B

5 YR

1 24V̲IN

5 RB

Br 2

6 B

3 4

7 V

3 GND

R PILOT̲SHUT-OFF̲SW

1 2

12V̲SOCKET YR

FUEL̲PUMP

IGNI 2 GND3 GND6

12V(SW)

2 B 2 B 2 B

WR G L 7+ 1.25 14+ 3 18+ 3

4+ 5 W 8+ 3 R

16+ 2 YB

1+ 5 W

FUSE̲BOX2

A23

DCDC 12̲OUT

1 2 PILOT̲SHUT-OFF VALVE

STARTER̲RELAY

AVS R AVS B CAB

1 2

4 1

0.85

B19

L B

LINK

ENG̲STOP̲SW NORMAL G 3 STOP Y 5 NORMAL R 6 STOP W 2

G L

A17 A18

SF-3 AEX AEX

GyR

W W LY

B 8 R 2 0.85 L 3 0.85

B21

ACG E

CASE̲EARTH

W W

8f 2f 2f

R4 STARTER CUT

AEX AEX

8f B S E

4 G SF-3 5

2 4

2 5 4

1 3

2 5 4

DIODE5 2 B AVSS A K

R AV

B SF-3

FORK̲10

B S

4 5

USB

W SF-3 2 B

STARTER M

1 3 R12 LOCK

BATTERY̲RELAY

5 R 2 W B S 1

G BR G

19+ 3 R 13+ 2 G

DIODE1 K 2 W AVSS A

2 B

AVSS

60 -

BATTERY

W W W LY

5 5 0.85 0.85

60 R -

AVXS AVXS AEX AEX

2 YB

2 G DIODE3 A AVSS

15+ 3 W

AVSS AVXS

11+ 5 W

AVXS

3 R 2 W 5 W

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

5 W

1 59 2

L WR

AVXS

R5 KEY̲ON̲CUT

2 5 4

0.85 2

AVXS

R W W

AEX

3 R

R R

DISCONNECT̲SW

3 RW

2 RW

61 13

1 3

2 5 4

RW LY

32- 10A 21- 10A

5 1 4 3

3f W 3f W 3f L 2f WR

W5 1 4 3

G L

REGULATOR

ALTERNATOR

A4 A3 D1 D9

3 G

3 1 3 R2 ECU

2 5 4

V RW G L G L E30 E28 E23 E31

F18 D26

1.25 1.25 1.25 D5 D6 D7 F25 C32

G L

G AVSSCS L AVSSCS

52 53 AVSS AVSS

AVSSCS AVSSCS

G L

V60 V77

V64 V81

G AVSSCS L AVSSCS

14 RB AVSS V76

4 AVS

CAB/H̲4

YW YW V40 V57

26 GyR AVSS V50

2 A B

15 16 13 14

0.75

V1 V3 V5

1.25 1.25 1.25

L AVSS L AVSS L AVSS

16 BrY V74

27 CAB/H̲2

GyR

R R R RB VR

V76

4 ECM

TDFY-02-05-008-1 ja 1-

Key Switch

Fuse Box 1

ECM Main Relay

ECM

Emergency Stop Circuit CAUTION Do not use engine stop switch (3) unless absolutely necessary. When the engine stops due to the machine failure, do not start the machine until the repair is completed. When the engine does not stop because of problems where the machine has failed or is damaged with key switch (1) set in the OFF position, set engine stop switch (3) to the ON position (lower position). Then, the engine stops. After that, return engine stop switch (3) to the OFF position (up). 1. If the engine does not stop after key switch (1) is set to the OFF position, the terminal B continues to be connected to the terminal M in key switch (1). 2. When engine stop switch (3) is set to the ON position at this time, current from fuse #17 flows to terminal #V50 of ECM (4).

TOJBQ40-EN-00(07/02/2020)

T2-5-14

SECTION2 SYSTEM Group5 Electrical System 3. ECM (4) recognizes that engine stop switch (3) is in the ON position. ECM (4) stops the fuel injection of the injector and stops the engine.

NOTE Even if the starter rotates with engine stop switch (3) set in the ON position, the engine does not start.

3 TDFY-02-05-023-1 ja 3-

Engine Stop Switch

TOJBQ40-EN-00(07/02/2020)

T2-5-15

SECTION2 SYSTEM Group5 Electrical System M

B G1 G2 ACC M ST

KEY̲SW

H OFF ACC ON START

L 3 L

3 W

R11 1 3 ACC̲CUT

3 R

A E

R AVX W AV WB AEX B

38+ 5

27+ 2 YR 36+ 2 RW

W 32+ 5

22+

32- 10A 21- 10A

5 W

28+ 24+

34+ 3 R 25+ 2 YB

FUSE̲BOX2

IGNI 2 GND3 GND6

12V(SW) 24V̲IN

Y 2

12V̲UNIT

37- 10A

39- 5A 26- 5A 27- 10A 36- 5A 23- 20A USB

38- 10A

31- 5A

4 9 10 17 6 20 5 7 14 18

33- 10A

10A 10A 20A 20A 5A 10A 16 12 11 3 15 8 2 1 19 13

282435342529-

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

SOCKET(12V) 1.25 YR

2 1.25

5 YR

1 24V̲IN

5 RB

Br 2

6 B

7 V

3 4

3 GND

R PILOT̲SHUT-OFF̲SW

12V̲SOCKET YR

FUEL̲PUMP

A23

DCDC 12̲OUT

2 B 2 B 2 B

WR G L 7+ 1.25 14+ 3 18+ 3

4+ 5 W 8+ 3 R

16+ 2 YB

19+ 3 R 13+ 2 G

4 5

1 2 PILOT̲SHUT-OFF VALVE

STARTER̲RELAY

AVS R AVS B CAB

1 2

4 1

L B

LINK

0.85

B19

ENG̲STOP̲SW NORMAL G 3 Y 5 STOP NORMAL R 6 W 2 STOP

G L

A17 A18

SF-3 AEX AEX

W W LY

GyR

B 8 R 2 0.85 L 3 0.85

B21

ACG E

CASE̲EARTH

W W

8f 2f 2f

R4 STARTER CUT

AEX AEX

8f B S E

4 G SF-3 5

2 4

2 5 4

1 3

2 5 4

DIODE5 2 B AVSS A K

R AV

B SF-3

FORK̲10

B S

USB

W SF-3 2 B

STARTER M

1 3 R12 LOCK

BATTERY̲RELAY

5 R 2 W B S 1

2 YB

G BR G

11+ 5 W

DIODE1 K 2 W AVSS A

2 B

AVSS

60 -

BATTERY

W W W LY

5 5 0.85 0.85

60 R -

AVXS AVXS AEX AEX

2 G DIODE3 A AVSS

15+ 3 W

AVSS AVXS

1+ 5 W

AVXS

3 R 2 W 5 W

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

5 W

1 59 2

L WR

AVXS

R5 KEY̲ON̲CUT

2 5 4

0.85 2

AVXS

R W W

AEX

3 R

R R

DISCONNECT̲SW

3 RW

2 RW

61 13

1 3

2 5 4

RW LY

22- 10A

5 1 4 3

3f W 3f W 3f L 2f WR

W5 1 4 3

G L

REGULATOR

A4 A3 D1 D9

3 G

ALTERNATOR

1 3 R2 ECU

2 5 4

V RW G L G L E30 E28 E23 E31

F18 D26

1.25 1.25 1.25 D5 D6 D7 F25 C32

G L

G AVSSCS L AVSSCS

52 53 AVSS AVSS G L

G L

V60 V77

V64 V81

G AVSSCS L AVSSCS

14 RB AVSS V76

4 AVS

CAB/H̲4

YW YW V40 V57

26 GyR AVSS V50

AVSSCS AVSSCS

A B

15 16 13 14

V50

0.75

V1 V3 V5

1.25 1.25 1.25

L AVSS L AVSS L AVSS

16 BrY V74

27 CAB/H̲2

GyR

R R R RB VR

4 ECM TDFY-02-05-009-1 ja

Key Switch

Fuse Box 1

Engine Stop Switch

ECM

Monitor Circuit of Electrical System The major functions and components in the monitor circuit are as follows. ● The security circuit disconnects current for engine starting from the key switch according to the signals from the external alarm system or monitor controller. At the same time, the security circuit turns OFF the pilot shut-off solenoid valve and disconnects the pilot circuit. The security circuit sounds the security horn at this time. (Monitor Controller, Security Horn Relay) ● The aerial angle circuit controls the camera image displayed on the monitor. ● The control lever auto pilot shut-off function turns OFF the pilot shut-off solenoid valve when performing front attachment, swing, or travel operation with the pilot shut-off lever set to the UNLOCK position. ● The seat belt reminder function activates the monitor indicator and buzzer depending on the state of the seat belt switch, engine operation, and pilot shut-off lever. ● The radio circuit operates the radio. (Monitor Controller, Switch Panel, Radio) TOJBQ40-EN-00(07/02/2020)

T2-5-16

SECTION2 SYSTEM Group5 Electrical System ● The air conditioner circuit operates the air conditioner. (Monitor Controller, Switch Panel, Air Conditioner Unit)

Security Circuit 1. When any one of the following conditions exists, monitor controller (4) connects terminals #B31 and #B32 to the ground inside. External alarm signal from e-Service: Yes

•

• Numerical keypad password input error signal: Yes 2. Therefore, security horn relay (6) and starter cut relay (1) are excited. 3. When security horn relay (6) is excited, current from fuse #9 activates security horn (5). 4. When starter cut relay (1) is excited, the circuit between terminal ST in key switch (3) and terminal S of starter relay (7) is disconnected. 5. Therefore, even if key switch (3) is set to the START position, the engine does not start. ST B G1 G2 ACC M ST

L 3 L L

3 W

R11 1 3 ACC̲CUT

3 R

A E

8f 2f 2f

W AV WB AEX B

38+ 5

22+

27+ 2 YR 36+ 2 RW

W 32+ 5

22- 10A

5 W

28+ 24+

34+ 3 R 25+ 2 YB

WR G L 7+ 1.25 14+ 3 18+ 3

2 B 2 B 2 B

4+ 5 W 8+ 3 R

16+ 2 YB

1+ 5 W

19+ 3 R 13+ 2 G

15+ 3 W

11+ 5 W

Y 2

12V̲UNIT

39- 5A 26- 5A 27- 10A 36- 5A 23- 20A

37- 10A

38- 10A

31- 5A

4 9 10 17 6 20 5 7 14 18

USB

16 12 11 3 15 8 2 1 19 13

33- 10A

20A 10A 5A 5A 20A 5A 5A 5A 5A 5A

282435342529-

10A 10A 20A 20A 5A 10A

R1 2 5 4 LOAD DUMP

R4 STARTER CUT

SOCKET(12V) 1.25 YR

15 WL

FUEL̲PUMP

GLOW̲PLUG RELAY

4 2

5 BY AEX 1 ENG̲4

GLOW̲PLUG

PILOT̲SHUT-OFF̲SW

5 RB

Br 2

6 B

7 V

3 4

Br GY

2 1.25

12V̲SOCKET YR

B SF-3

5 YR

1 24V̲IN

3 GND

4 L

0.85

RL RL

1 2

AVS R AVS B CAB

1 2

4 1

L B

LINK

ENG̲STOP̲SW 3 NORMAL G Y 5 STOP NORMAL R 6 W 2 STOP

0.85

B19

B31

G L

A17 A18

B31

SF-3 AEX AEX

5 GyR

W W LY

B21

CASE̲EARTH

B 8 R 2 0.85 L 3 0.85

ALTERNATOR

R R 2 5 4

ACG

REGULATOR

24V̲IN

4 G SF-3 5

PILOT̲SHUT-OFF VALVE

STARTER̲RELAY

3 1

IGNI 2 GND3 GND6

12V(SW)

W W

B S E

FUSE̲BOX2

A23

DCDC 12̲OUT

USB

AEX AEX

2 4

1 3

2 5 4

DIODE5 2 B AVSS A K

R AVX

1 3

W AV

R AV

FORK̲10

B S

4 5

W SF-3 2 B

STARTER M

1 3 R12 LOCK

VR 58

1 3

5 R 2 W B S 1

BATTERY̲RELAY

G BR G

2 YB

5A 10A 5A 20A 10A 30A 15A 20A 10A 5A

2 B

AVSS

60 -

BATTERY

W W W LY

5 5 0.85 0.85

60 R -

AVXS AVXS AEX AEX

DIODE3 A AVSS

R5 KEY̲ON̲CUT

2 5 4

2 G

AVSS AVXS

2 2

AVXS

3 R 2 W 5 W

5 W

1 59 2

L WR

AVXS

0.85 2

AVXS

R W W

DIODE1 A K 2 W AVSS

AEX

3 R

R R

2 RW

DISCONNECT̲SW

1 3

2 5 4

61 13

3 RW

RW LY

32- 10A 21- 10A

5 1 4 3

3f W 3f W 3f L 2f WR

W5 1 4 3

START 1 2

KEY̲SW

H OFF ACC ON START

RL 1 R3 SEC̲HORN 1 3 PG 2

G L

SEC̲HORN 2 5 4

A4 A3 D1 D9

GB B32

B32

3 G

1 3

2 5 4

R2 ECU

V RW F18 D26

G L G L E30 E28 E23 E31

F25 C32

G L

G AVSSCS L AVSSCS

52 53

RB AVSS

AVSS AVSS G L

G L

V76

V60 V77

V64 V81

CAB/H̲4

YW YW V40 V57

AVS

GyR AVSS V50

BrY V74

AVSSCS AVSSCS

15 16 13 14

A B

0.75

V1 V3 V5

1.25 1.25 1.25

L AVSS L AVSS L AVSS

G AVSSCS L AVSSCS

16 YL V91

27 CAB/H̲2

GyR

RB VR

TDFY-02-05-010-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-5-17

SECTION2 SYSTEM Group5 Electrical System 12-

Starter Cut Relay Fuse Box 1

34-

Key Switch Monitor Controller

56-

Security Horn Security Horn Relay

Starter Relay

Aerial Angle Circuit 1. The images of rear view camera (4), camera left (5), and camera right (6) are sent to aerial angle controller (3). 2. The images combined in aerial angle controller (3) are displayed on monitor (2) through monitor controller (1). 3. The view of the combined image is switched between Machine Environment, Machine Environment + Rear, Rear + Right + Left, Machine Environment + Rear + Right, and Rear + Right by using aerial angle switch (7). 2 G3 G2 G5 G6 G1 G4

O G R B Br L

D10 D12 D16 D14 D15

R BY W Gy

D11 D13 D8 D6 D7

W Gy

1 4 5 6 3 2 1 2 3 4

CAMERA̲POW CAMERA̲GND

W Gy W Gy

5 6 2 3 1

AERIAL̲ANGLE̲SW 8 9 6

B WG WL

1 2 3

Monitor Controller Monitor

34-

W Gy RW LW B

26 6 7

B WG WL

21 29 28

1 2 3 4

R B W Gy

1 2 3 4

VCC GND SIGNAL S̲GND

RL BL W GyB

5 6 7 8

RL BL W GyB

1 2 3 4

VCC GND SIGNAL S̲GND

RY BY W GyR

RY 9 10 BY 11 W 12 GyR

1 2 3 4

VCC GND SIGNAL S̲GND

12 32 11 31

R BY W Gy

16 36 15 35

14 34 13 33

1 2 3 4

R BY W Gy

REAR̲CAMERA

LEFT̲CAMERA

RIGHT̲CAMERA

12-

19 39 20 40 5

Aerial Angle Controller Rear View Camera

56-

Camera Left Camera Right

TDFY-02-05-011-1 ja Aerial Angle Switch

Control Lever Automatic Pilot Shut-Off Circuit 1. When the pilot shut-off lever is set to the UNLOCK position and one of the following conditions exists, MC (6) connects terminal #C32 to the ground for approx. 3 seconds. •

Front pilot pressure sensor (7): Outputting signal

• Travel pilot pressure sensor (8): Outputting signal 2. Therefore, pilot shut-off relay (1) is excited. 3. When pilot shut-off relay (1) is excited, current flowing from terminal M of the key switch to the pilot shut-off solenoid valve (9) is shut off so that the pilot shut-off solenoid valve (9) is turned OFF. 4. Pressure oil supplied from the pilot pump to the pilot valve is blocked by the pilot shut-off solenoid valve (9). 5. At the same time, MC (6) sends the signal to monitor controller (4) by using the CAN communication. 6. Monitor controller (4) displays an alarm on monitor (5) and sounds buzzer (3).

TOJBQ40-EN-00(07/02/2020)

T2-5-18

SECTION2 SYSTEM Group5 Electrical System 5 G3 G2 G5 G6 G1 G4

1 2

SEATBELT̲WARN̲SW

1 3

YB B

4 YB 5 B

O G R B Br L

1 4 5 6 3 2

B14

R12 LOCK 2 5 4

2 1 2

1 2

PILOT̲SHUT-OFF VALVE

PILOT̲SHUT-OFF̲SW

Br 2

3 4

Br GY

5 RB

6 B

7 V

4 B34

CASE̲EARTH

AVSSCS AVSSCS

G L

1 2

A4 A3 D1 D9

G L GB

B̲CAN̲H B̲CAN̲L

G AVSSCS L AVSSCS E23 E31

CAN F18

VR C32

4 BODY-CAN H 10 BODY-CAN L

C32

TRAVEL

FRT

D16

6 MC

8 7 TDFY-02-05-012-1 ja

a- From Key Switch Terminal M 123-

Pilot Shut-Off Relay Pilot Shut-Off Switch Buzzer

456-

Monitor Controller Monitor MC

789-

Front Pilot Pressure Sensor Travel Pilot Pressure Sensor Pilot Shut-Off Solenoid Valve

Seat Belt Reminder Circuit 1. If you do not wear your seat belt, seat belt switch (2) is turned OFF. 2. When seat belt switch (2) is turned OFF, monitor controller (4) displays an icon on monitor (5). 3. Under this condition, when the pilot shut-off lever is set to the UNLOCK position, monitor controller (4) sounds buzzer (3) in approx. 5 seconds.

TOJBQ40-EN-00(07/02/2020)

T2-5-19

SECTION2 SYSTEM Group5 Electrical System 5 G3 G2 G5 G6 G1 G4

2 1 2

SEATBELT̲WARN̲SW

1 3

YB B

4 YB 5 B

O G R B Br L

1 4 5 6 3 2

B14

R12 LOCK 2 5 4

1 1 2

1 2

PILOT̲SHUT-OFF VALVE

PILOT̲SHUT-OFF̲SW

Br 2

3 4

Br GY

5 RB

6 B

7 V

B34

CASE̲EARTH

AVSSCS AVSSCS

G L

1 2

A4 A3 D1 D9

G L GB

B̲CAN̲H B̲CAN̲L

G AVSSCS L AVSSCS E23 E31

CAN F18

VR C32

4 BODY-CAN H 10 BODY-CAN L

6 MC TDFY-02-05-013-1 ja

a- From Key Switch Terminal M 12-

Pilot Shut-Off Switch Seat Belt Switch

34-

Buzzer Monitor Controller

56-

Monitor MC

Radio Circuit 1. The operation on switch panel (2) is displayed on monitor (1) through monitor controller (3). 2. When radio (5) is operated on switch panel (2), the signal is sent to monitor controller (3) by using the CAN communication. 3. Monitor controller (3) sends the signal to radio (5) by using the CAN communication and radio (5) is operated.

TOJBQ40-EN-00(07/02/2020)

T2-5-20

SECTION2 SYSTEM Group5 Electrical System 1

4 2

3 ฀

฀

5 CAN TDFY-02-05-014-1 ja 12-

Monitor Switch Panel

34-

Monitor Controller Fuse Box 1

Radio

Air Conditioner Circuit 1. The operation on switch panel (2) is displayed on monitor (1) through monitor controller (3). 2. When the air conditioner is operated on switch panel (2), the signal is sent to monitor controller (3) by using the CAN communication. 3. Monitor controller (3) sends the signal to air conditioner unit (5) by using the CAN communication and air conditioner unit (5) is operated.

TOJBQ40-EN-00(07/02/2020)

T2-5-21

SECTION2 SYSTEM Group5 Electrical System 1

4 2

3 ฀

5 ฀

฀

CAN TDFY-02-05-015-1 ja 12-

Monitor Switch Panel

34-

Monitor Controller Fuse Box 1

Air Conditioner Unit

Accessory Circuit The major functions and components in the accessory circuit are as follows. ● The work light circuit turns on the work light and boom light. (Monitor Controller, Switch Panel, Work Light Relay) ● The wiper circuit operates the wiper including intermittent operation and the washer. (Monitor Controller, Switch Panel, Wiper Relay, Washer Relay) ● The cab light circuit turns on/off the cab light by shifting the switch or by opening/closing the door.

Work Light Circuit (Work Light: ON) 1. When work light switch (4) is set to the 1 position, current from fuse #1 flows to terminal #B24 of monitor controller (5) and switch panel (3), and connects to the ground in switch panel (3). 2. Therefore, work light relay 1 (9) is turned ON and current from fuse #1 turns on work light (8). 3. Switch box controller (11) sends the signal equivalent to the operating condition of work light switch (4) to monitor controller (5) by using the CAN communication.

TOJBQ40-EN-00(07/02/2020)

T2-5-22

SECTION2 SYSTEM Group5 Electrical System

őŖŔŉ

˩ˡ˪˱ Ŕņŕ

ůİŮŪůġ

˩˫ˠˡ

őŖŔŉ

䰙

信

˩˫ˠˡ

䩩

ŕŖŏņ

a b c

őŖŔŉ

ŔŐŖœńņ łŎİŇŎ őŖŔŉ

őŖŔŉ

ŗŐōİőŘœȁ

łŖŕŐ İŐŇŇ łŖŕŐ

ůİŮŪůġ ůİŮŪůġ

2 ŐŇŇ

3 Ŋŏŕ ŐŇŇ

Őŏ őŖŔŉġ

ＯＦＦ

łń

ń Őŏ

Ŕŕł œŕ

0 Ŋŏŕ

Őŏ

ŐŇŇ őŖŔŉ

TDFY-02-05-018-1 ja

a- OFF Position b- 1 position 4-

c- 2 position

Work Light Switch

TOJBQ40-EN-00(07/02/2020)

T2-5-23

SECTION2 SYSTEM Group5 Electrical System 2

6 1 5 ฀

10 ฀

฀

B24 B23

฀

8 7 11 CAN

234-

Monitor Switch Panel Work Light Switch

567-

Monitor Controller Fuse Box 1 Boom Light

8910-

Work Light Work Light Relay 1 Work Light Relay 2

11-

TDFY-02-05-016-1 ja Switch Box Controller

Work Light Circuit (Work Light, Work Light (Cab Upper), and Boom Light: ON) 1. When work light switch (4) is set to the 2 position, current from fuse #1 flows to terminals # B23 and #B24 of monitor controller (5) and switch panel (3), and connects to the ground in switch panel (3). 2. Therefore, work light relay 1 (9) and work light relay 2 (10) are turned ON and current from fuse #1 turns on work light (8), work light (cab upper) (12) and boom light (7). 3. Switch box controller (11) sends the signal equivalent to the operating condition of work light switch (4) to monitor controller (5) by using the CAN communication.

TOJBQ40-EN-00(07/02/2020)

T2-5-24

SECTION2 SYSTEM Group5 Electrical System

őŖŔŉ

˩ˡ˪˱ Ŕņŕ

ůİŮŪůġ

˩˫ˠˡ

őŖŔŉ

䰙

信

˩˫ˠˡ

䩩

ŕŖŏņ

a b c

őŖŔŉ

ŔŐŖœńņ łŎİŇŎ őŖŔŉ

őŖŔŉ

ŗŐōİőŘœȁ

łŖŕŐ İŐŇŇ łŖŕŐ

ůİŮŪůġ ůİŮŪůġ

2 ŐŇŇ

3 Ŋŏŕ ŐŇŇ

Őŏ őŖŔŉġ

ＯＦＦ

łń

ń Őŏ

Ŕŕł œŕ

0 Ŋŏŕ

Őŏ

ŐŇŇ őŖŔŉ

TDFY-02-05-018-1 ja

a- OFF Position b- 1 position 4-

c- 2 position

Work Light Switch

TOJBQ40-EN-00(07/02/2020)

T2-5-25

SECTION2 SYSTEM Group5 Electrical System 2

6 1 5 ฀

10 ฀

฀

B24 B23

฀

12 7

11 CAN

234-

Monitor Switch Panel Work Light Switch

567-

Monitor Controller Fuse Box 1 Boom Light

8910-

Work Light Work Light Relay 1 Work Light Relay 2

1112-

TJAQ-02-05-002-1 ja Switch Box Controller Work Light (Cab Upper)

Wiper Circuit 1. When wiper/washer switch (4) is set to the INT. position, switch box controller (5) sends the signal to monitor controller (6) according to the set interval by using the CAN communication. 2. Monitor controller (6) connects terminal #B29 to the ground inside according to the input interval. 3. Therefore, wiper relay (8) is turned ON and OFF repeatedly. 4. When wiper relay (8) is ON, current from fuse #2 flows to wiper motor (9) and the wiper is operated.

TOJBQ40-EN-00(07/02/2020)

T2-5-26

SECTION2 SYSTEM Group5 Electrical System

őŖŔŉ

˩ˡ˪˱ Ŕņŕ

ůİŮŪůġ

˩˫ˠˡ

őŖŔŉ

䰙

信

˩˫ˠˡ

䩩

ŕŖŏņ

őŖŔŉ

ŔŐŖœńņ łŎİŇŎ őŖŔŉ

őŖŔŉ

ŗŐōİőŘœȁ

łŖŕŐ İŐŇŇ łŖŕŐ

ůİŮŪůġ ůİŮŪůġ

2 3

ŐŇŇ

Ŋŏŕ

ŐŇŇ

Őŏ őŖŔŉġ

ＯＦＦ

łń

ń Őŏ

Ŕŕł œŕ

4 1

0 Ŋŏŕ

Őŏ

ŐŇŇ őŖŔŉ

TDFY-02-05-018-2 ja 4-

Wiper/Washer Switch

No.

INT. Position

Set Time

Slow

8 seconds

Middle

6 seconds

Fast

3 seconds

TOJBQ40-EN-00(07/02/2020)

T2-5-27

SECTION2 SYSTEM Group5 Electrical System 1

7 3 2

17 6 ฀

11 ฀

B29 B26

฀

CAN

10 9 TDFY-02-05-017-1 ja 145-

Monitor Wiper/Washer Switch Switch Box Controller

678-

Monitor Controller Fuse Box 1 Wiper Relay

91011-

Wiper Motor Washer Motor Washer Relay

Washer Circuit 1. While wiper/washer switch (4) is held down, switch box controller (5) sends the signal to monitor controller (6) by using the CAN communication. 2. Monitor controller (6) connects terminal #B26 to the ground inside and washer relay (11) is excited. 3. Current from fuse #2 flows to washer motor (10) and washer liquid is jetted. 4. When pushing wiper/washer switch (4) for 1.4 seconds or more, monitor controller (6) turns ON washer relay (11) and wiper relay (8). 5. Therefore, the washer and wiper are operated at the same time.

TOJBQ40-EN-00(07/02/2020)

T2-5-28

SECTION2 SYSTEM Group5 Electrical System

őŖŔŉ

˩ˡ˪˱ Ŕņŕ

ůİŮŪůġ

˩˫ˠˡ

őŖŔŉ

䰙

信

˩˫ˠˡ

䩩

ŕŖŏņ

őŖŔŉ

ŔŐŖœńņ łŎİŇŎ őŖŔŉ

őŖŔŉ

ŗŐōİőŘœȁ

łŖŕŐ İŐŇŇ łŖŕŐ

ůİŮŪůġ ůİŮŪůġ

2 3

ŐŇŇ

Ŋŏŕ ŐŇŇ

Őŏ őŖŔŉġ

ＯＦＦ

łń

ń Őŏ

Ŕŕł œŕ

4 1

0 Ŋŏŕ

Őŏ

ŐŇŇ őŖŔŉ

TDFY-02-05-018-3 ja 4-

Wiper/Washer Switch

7 3 2

17 6 ฀

11 ฀

B29 B26

฀

CAN

10 9 TDFY-02-05-017-1 ja

TOJBQ40-EN-00(07/02/2020)

T2-5-29

SECTION2 SYSTEM Group5 Electrical System 145-

Monitor Wiper/Washer Switch Switch Box Controller

678-

Monitor Controller Fuse Box 1 Wiper Relay

91011-

Wiper Motor Washer Motor Washer Relay

Cab Light Circuit (Cab Light Switch: Door Interlocking Position (Key Switch: ON)) 1. When cab light switch (7) is set to door interlocking position (5), current from fuse #9 flows to terminal #B3 of monitor controller (4). 2. When the cab door is closed, door open/close switch (3) is turned ON and terminal #B10 of monitor controller (4) is connected to the ground. 3. Monitor controller (4) recognizes that the cab door is closed and disconnects terminal #B3 inside from the ground. Consequently, cab light (8) is not turned on. 4. When the cab door is opened, door open/close switch (3) is turned OFF and terminal #B10 of monitor controller (4) is disconnected from the ground. 5. Monitor controller (4) recognizes that the cab door is open and connects terminal #B3 to the ground inside for 30 seconds. 6. Therefore, current from fuse #9 flows to terminal #B3 of monitor controller (4) and turns on cab light (8). 7. After cab light (8) is turned on for 30 seconds or when the cab door is closed, monitor controller (4) disconnects terminal #B3 inside from the ground. 8. Therefore, cab light (8) is tuned off. 9. Consequently, when cab light switch (7) is in door interlocking position (5), cab light (8) is turned on/off by opening/ closing the cab door.

NOTE In case the cab door is open and key switch (1) is set to the ON position, cab light (8) is not turned on with cab light switch (7) set in door interlocking position (5). When closing the cab door once and opening it again, cab light (8) can be turned on.

TOJBQ40-EN-00(07/02/2020)

T2-5-30

SECTION2 SYSTEM Group5 Electrical System 1 ON

B10 2 9 ฀

฀

B3 B4

฀

8 7

12-

Key Switch Fuse Box 1

34-

Door Open/Close Switch Monitor Controller

56-

Door Interlocking Position ON Position

78-

TDFY-02-05-022-1 ja Cab Light Switch Cab Light

Cab Light Circuit (Cab Light Switch: ON Position) 1. Monitor controller (4) connects terminal #B4 to the ground inside. 2. When cab light switch (7) is set to ON position (6), current from fuse #9 flows to terminal #B4 of monitor controller (4). 3. Consequently, when cab light switch (7) is in ON position (6), cab light (8) is always turned on.

TOJBQ40-EN-00(07/02/2020)

T2-5-31

SECTION2 SYSTEM Group5 Electrical System 1 ON

B10 2 9 ฀

฀

B3 B4

฀

8 7

12-

Key Switch Fuse Box 1

TOJBQ40-EN-00(07/02/2020)

34-

Door Open/Close Switch Monitor Controller

56-

T2-5-32

Door Interlocking Position ON Position

78-

TDFY-02-05-022-1 ja Cab Light Switch Cab Light

TOJBQ40-EN-00(07/02/2020)

MEMO

TOJBQ40-EN-00(07/02/2020)

SECTION3 COMPONENT OPERATION Group1 Pump Device Outline of Pump Device The pump device consists of main pump (pump 1 (1), pump 2 (6)), pilot pump (5), oil cooler fan pump (4), radiator fan pump (3), control solenoid valves, and sensors. The engine output power is transmitted via coupling (13). After being distributed by the gear, the engine output power drives main pump (pump 1 (1), pump 2 (6)), and radiator fan pump (3). Pilot pump (5) and oil cooler fan pump (4) are driven via radiator fan pump (3). The main pump (pump 1 (1), pump 2 (6)) and radiator fan pump (3) are swash plate type variable displacement axial plunger pumps. Pump 1 (1), pump 2 (6), and radiator fan pump (3) are contained in one housing. Pilot pump (5) and oil cooler fan pump (4) are gear pump. Pump delivery pressure sensors (7, 8) and pump displacement control pressure sensors (9, 10) are installed in order to control the pump and valve. (Refer to SYSTEM/Control System.) 1

3 2

TJBQ-05-04-001-2 ja

TOJBQ40-EN-00(07/02/2020)

T3-1-1

SECTION3 COMPONENT OPERATION Group1 Pump Device 1234-

Pump 1 Fan Pump Control Solenoid Valve Radiator Fan Pump Oil Cooler Fan Pump

567-

Pilot Pump Pump 2 Pump 2 Delivery Pressure Sensor

8910-

Pump 1 Delivery Pressure Sensor Pump 1 Displacement Control Pressure Sensor Pump 2 Displacement Control Pressure Sensor

111213-

Pump 2 Control Solenoid Valve Pump 1 Control Solenoid Valve Coupling

Outline of Main Pump The main pump supplies pressure oil to actuate the hydraulic components such as motors or cylinders. The main pump consists of pump 1 and pump 2. Shaft (3) is connected to cylinder block (5) by a spline joint. When shaft (3) is rotated with cylinder block (5) together, plunger (4) oscillates in cylinder block (5) and hydraulic oil is drawn and delivered. Each pump is equipped with regulator (1) which controls the pump delivery flow rate. 2

3 5 7 1 12-

Regulator Housing

34-

Shaft Plunger

56-

Cylinder Block Valve Plate

TJBQ-03-01-001-1 ja Swash Plate

Operational Principle of Main Pump 1. Engine torque is transferred to shaft (3). 2. When shaft (3) rotates, plunger (4) rotates together with cylinder block (5). 3. Plunger (4) slides on swash plate (7). 4. Plunger (4) reciprocates in the cylinder block (5) bore and alternately hydraulic oil is drawn and delivered.

TOJBQ40-EN-00(07/02/2020)

T3-1-2

SECTION3 COMPONENT OPERATION Group1 Pump Device 4

3 5 7 8 TJBQ-03-01-001-3 ja 34-

Shaft Plunger

56-

Cylinder Block Valve Plate

78-

Swash Plate Servo Piston

Increasing and Decreasing of Main Pump Delivery Flow Rate 1. The main pump delivery flow rate is controlled by changing the displacement angle of swash plate (7) to increase or decrease the plunger (4) stroke. 2. Operation of servo piston (8) changes inclination of swash plate (7). 4

3 5 7 8 TJBQ-03-01-001-3 ja 34-

Shaft Plunger

56-

Cylinder Block Valve Plate

78-

Swash Plate Servo Piston

Outline of Regulator (For Main Pump) Regulator (11) controls the main pump flow rate in response to flow rate control pressure from the pump control solenoid valve (12) so that the engine output torque is not exceeded. Pump 1 and pump 2 are equipped with regulator (11) for each. The major component parts of the regulator (11) include spring (13), sleeve (14), spool (15), piston (16), and pump control solenoid valve (12). TOJBQ40-EN-00(07/02/2020)

T3-1-3

SECTION3 COMPONENT OPERATION Group1 Pump Device According to flow rate control pressure from the pump control solenoid valve (12), each regulator (11) opens or closes the circuit to servo piston (17) and the displacement angle of swash plate (18) is changed. Thus, the pump delivery flow rate is controlled. 1. The control is performed by increasing or decreasing the flow rate control pressure by the pump control solenoid valve (12). 2. Primary pilot pressure Pg acts on spool (15), and also always acts on the small chamber side of servo piston (17). 3. Primary pilot pressure Pg is decreased into flow rate control pressure that acts on piston (16) when pump control solenoid valve (12) is operated.

11 12 11-

Regulator

12-

Pump Control Solenoid Valve

17-

Servo Piston

18-

TJBQ-03-01-001-2 ja Swash Plate

11 12

Pi 13

14 13 16

Pg Dr 22 21

17 15

20 b 18

a 19 TJBQ-03-01-002-1 ja

Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Pg- Primary Pilot Pressure 111213-

Regulator Pump Control Solenoid Valve Spring

TOJBQ40-EN-00(07/02/2020)

141516-

a- Displacement Angle Increase b- Displacement Angle Decrease Sleeve Spool Piston

171819-

T3-1-4

Servo Piston Swash Plate Main Pump

202122-

Link Pin Pin

SECTION3 COMPONENT OPERATION Group1 Pump Device Control by Pump Control Solenoid Valve (Minimum Flow Rate) 1. When the pump control solenoid valve (12) is OFF, spool (15) moves to the right by spring (13). 2. Primary pilot pressure Pg is routed through sleeve (14) and spool (15) and acts on the large chamber side of servo piston (17). 3. Primary pilot pressure Pg is also always acting on the small chamber side of servo piston (17) but servo piston (17) moves to the left due to a difference in area. 4. When servo piston (17) is moved, link (20) rotates clockwise by using pin (21) as the supporting point. 5. The end of link (20) is connected to sleeve (14) with pin (22) and sleeve (14) moves to the right. 6. Servo piston (17) moves until the notch part between sleeve (14) and spool (15) is closed and stops in the position where the notch part is fully closed. 7. As described above, the pump displacement angle reaches the minimum and the pump delivery flow rate is minimized. Q

Pi TJAQ-03-01-006-1 ja

Q- Flow Rate

Pi- Flow Rate Control Pressure 12

13 Dr

15 Pi

Pi 14 13

16 16

Dr 21

17 15

20 a

b 18

19 17 TJBQ-03-01-003-1 ja

Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Pg- Primary Pilot Pressure 121314-

Pump Control Solenoid Valve Spring Sleeve

TOJBQ40-EN-00(07/02/2020)

151617-

a- Displacement Angle Increase b- Displacement Angle Decrease Spool Piston Servo Piston

181920-

T3-1-5

Swash Plate Main Pump Link

2122-

Pin Pin

SECTION3 COMPONENT OPERATION Group1 Pump Device Control by Pump Control Solenoid Valve (Increase of Flow Rate) 1. The pump control solenoid valve (12) increases flow rate control pressure Pi according to the signals from MC. 2. Piston (16) moves spool (15) to the left until it balances with the spring force of spring (13) by flow rate control pressure Pi. 3. When spool (15) is moved, the large chamber side of servo piston (17) connects to the hydraulic oil tank through the inside of spool (15). 4. On the small chamber side of servo piston (17), primary pilot pressure Pg always acts so that servo piston (17) is moved to the right and pressure oil on the large chamber side returns to the hydraulic oil tank. 5. When servo piston (17) is moved, link (20) rotates counterclockwise by using pin (21) as the supporting point. 6. The end of link (20) is connected to sleeve (14) with pin (22) and sleeve (14) moves to the left. 7. Servo piston (17) moves until the notch part between sleeve (14) and spool (15) is closed and stops in the position where the notch part is fully closed. 8. As described above, the pump displacement angle increases and the pump delivery flow rate increases. The increased amount of the pump delivery flow rate is proportional to the increased amount of the flow rate control pressure Pi. Q

Pi TJAQ-03-01-011-1 ja

Q- Flow Rate

Pi- Flow Rate Control Pressure 12

13 Dr

15 16 Pi

Pi 14 13 16

Pg Dr

22 21 20 a

b 18

17 15

21 17 TJBQ-03-01-004-1 ja

Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Pg- Primary Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

a- Displacement Angle Increase b- Displacement Angle Decrease

T3-1-6

SECTION3 COMPONENT OPERATION Group1 Pump Device 121314-

Pump Control Solenoid Valve Spring Sleeve

151617-

Spool Piston Servo Piston

181920-

Swash Plate Main Pump Link

2122-

Pin Pin

Control by Pump Control Solenoid Valve (Decrease of Flow Rate) 1. The pump control solenoid valve (12) decreases flow rate control pressure Pi according to the signals from MC. 2. Spool (15) moves right until it balances with the spring force of spring (13). 3. Pressure oil routed to piston (16) returns to the hydraulic oil tank through pump control solenoid valve (12). 4. When spool (15) is moved, primary pilot pressure Pg is routed through sleeve (14) and spool (15) and acts on the large chamber side of servo piston (17). 5. Primary pilot pressure Pg is also always acting on the small chamber side of servo piston (17) but servo piston (17) moves to the left due to a difference in area. 6. When servo piston (17) is moved, link (20) rotates clockwise by using pin (21) as the supporting point. 7. The end of link (20) is connected to sleeve (14) with pin (18) and sleeve (14) moves to the right. 8. Servo piston (17) moves until the notch part between sleeve (14) and spool (15) is closed and stops in the position where the notch part is fully closed. 9. As described above, the pump displacement angle decreases and the pump delivery flow rate decreases. The decreased amount of the pump delivery flow rate is proportional to the decreased amount of the flow rate control pressure Pi. Q

Pi TJAQ-03-01-012-1 ja

Q- Flow Rate

Pi- Flow Rate Control Pressure 12

13 Dr

15 Pi

Pi 14 13

16 16

Dr 21

17 15

20 a

b 18

19 17 TJBQ-03-01-003-1 ja

TOJBQ40-EN-00(07/02/2020)

T3-1-7

SECTION3 COMPONENT OPERATION Group1 Pump Device Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Pg- Primary Pilot Pressure 121314-

Pump Control Solenoid Valve Spring Sleeve

151617-

a- Displacement Angle Increase b- Displacement Angle Decrease Spool Piston Servo Piston

181920-

Swash Plate Main Pump Link

2122-

Pin Pin

Outline of Pump Control Solenoid Valve The pump control solenoid valve is installed in the main pump regulator. The pump control solenoid valve controls flow rate control pressure Pi for the regulators according to the signals from MC and increase or decrease the pump delivery flow rate.

Operation of Pump Control Solenoid Valve (When in Neutral) ● When neutral, spring (31) pushes spool (33) to the right and output port S (32) is connected to tank port (35). 35

33 31

TJBQ-03-01-005-1 ja 3132-

Spring Output Port S

3334-

Spool Port P

35-

Tank Port T

Operation of Pump Control Solenoid Valve (When Excited) 1. When the signals from MC are received, solenoid (36) pushes spool (33) to the left in proportion to the current value flowing to solenoid (36). 2. Pilot pressure oil flows to output port S (32) from port P (34). 3. Therefore, pressure at output port S (32) begins to increase. 4. This pressure at output port S (32) acts on stepped part (a) of spool (33). Spool (33) is pushed to the right due to difference in the pressure receiving area between stepped part (a). 5. When the pressure at output port S (32) increases and the force to push spool (33) to the right exceeds the force to push spool (33) to the left by solenoid (36), spool (33) is returned to the right to close the passage between output port S (32) and output port P (34). 6. Therefore, pressure at output port S (32) stops increasing.

TOJBQ40-EN-00(07/02/2020)

T3-1-8

SECTION3 COMPONENT OPERATION Group1 Pump Device 35

34 33

a TJBQ-03-01-006-1 ja

a- Stepped Part 3132-

Spring Output Port S

3334-

Spool Port P

3536-

Tank Port T Solenoid

Outline of Radiator Fan Pump The radiator fan pump supplies pressure oil to actuate fan motors. Shaft (3) is connected to cylinder block (5) by a spline joint. When shaft (3) is rotated with cylinder block (5) together, plunger (4) oscillates in cylinder block (5) and hydraulic oil is drawn and delivered. 1

8 4

6 2

5 12-

Regulator Housing

34-

Shaft Plunger

7 56-

Cylinder Block Valve Plate

Operational Principle of Radiator Fan Pump 1. The engine torque is transmitted to shaft (3). 2. When shaft (3) rotates, plunger (4) rotates together with cylinder block (5).

TOJBQ40-EN-00(07/02/2020)

T3-1-9

3 78-

TJAQ-03-01-013-1 ja Swash Plate Servo Piston

SECTION3 COMPONENT OPERATION Group1 Pump Device 3. Plunger (4) slides on swash plate (7). 4. Plunger (4) reciprocates in the cylinder block (5) bore and alternately hydraulic oil is drawn and delivered. 1

8 4

6 2

5 12-

Regulator Housing

34-

Shaft Plunger

7 56-

Cylinder Block Valve Plate

78-

TJAQ-03-01-013-1 ja Swash Plate Servo Piston

Increasing and Decreasing of Radiator Fan Pump Delivery Flow Rate 1. The fan pump delivery flow rate is controlled by changing the displacement angle of swash plate (7) to increase or decrease the plunger (4) stroke. 2. Operation of servo piston (8) changes inclination of swash plate (7). 1

8 4

6 2

5 12-

Regulator Housing

TOJBQ40-EN-00(07/02/2020)

34-

Shaft Plunger

7 56-

T3-1-10

Cylinder Block Valve Plate

3 78-

TJAQ-03-01-013-1 ja Swash Plate Servo Piston

SECTION3 COMPONENT OPERATION Group1 Pump Device Outline of Regulator (For Radiator Fan Pump) In response to flow rate control pressure from fan pump control solenoid valve (12), regulator (11) controls the radiator fan pump flow rate according to the temperature of the radiator. The major component parts of the regulator include spring (13), sleeve (14), spool (15), piston (16), and fan pump control solenoid valve (12). In response to flow rate control pressure from the fan pump control solenoid valve (12), regulator (11) opens or closes the circuit to servo piston (17) so that the displacement angle of swash plate (18) is changed. Therefore the pump delivery flow rate is controlled. Own pump delivery pressure Pd is routed through check valve (19) and acts on spool (15), and also always acts on the small chamber side of servo piston (17). Pilot primary pressure Psv from pilot pump (20) is decreased into flow rate control pressure that acts on piston (16) when the fan pump control solenoid valve (12) is operated. Pilot primary pressure Psv is routed through check valve (21) and combined with own pump delivery pressure Pd. 12

17 18

TJAQ-03-01-013-2 ja 1112-

Regulator Fan Pump Control Solenoid Valve

TOJBQ40-EN-00(07/02/2020)

1718-

Servo Piston Swash Plate

T3-1-11

SECTION3 COMPONENT OPERATION Group1 Pump Device 12

21 19 Psv

12 Pd

Dr Pi

16 13 22 23 24

16 15 a

18 25

20 25 22

18 TJAQ-03-01-014-1 ja

Pd- Pump Delivery Pressure Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure 11121314-

Regulator Pump Control Solenoid Valve Spring Sleeve

15161718-

Psv- Primary Pilot Pressure a- Displacement Angle Increase b- Displacement Angle Decrease Spool Piston Servo Piston Swash Plate

19202122-

Check Valve Pilot Pump Check Valve Pin

232425-

Pin Link Main Pump

Control by Fan Pump Control Solenoid Valve (Minimum Flow Rate) 1. When the fan pump control solenoid valve (12) is OFF, spool (15) moves to the left by spring (13). 2. Own pump delivery pressure Pd is routed through check valve (19), sleeve (14), and spool (15) and acts on the large chamber side of servo piston (17). Own pump delivery pressure Pd is also always acting on the small chamber side of servo piston (17) but servo piston (17) moves to the right due to a difference in area. 3. When servo piston (17) is moved, link (24) rotates counterclockwise by using pin (23) as the supporting point. 4. The end of link (24) is connected to sleeve (14) with pin (22) and sleeve (14) moves to the left. Servo piston (17) moves until the open part between sleeve (14) and spool (8) is closed and stops in the position where the open part is fully closed. 5. As described above, the pump displacement angle reaches the minimum and the pump delivery flow rate is minimized. Q

Pi TJAQ-03-01-006-1 ja

Q- Flow Rate

TOJBQ40-EN-00(07/02/2020)

Pi- Flow Rate Control Pressure

T3-1-12

SECTION3 COMPONENT OPERATION Group1 Pump Device Dr 15 Dr

Psv

22 2313 19

Psv

Pi Pd 16

13 16

15 22 23 24

14 a 20

b 18

25 20 18

25 TJAQ-03-01-015-1 ja

Pd- Pump 1 Delivery Pressure Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Psv- Primary Pilot Pressure 111213-

Regulator Fan Pump Control Solenoid Valve Spring

14151617-

a- Displacement Angle Increase b- Displacement Angle Decrease

Sleeve Spool Piston Servo Piston

18192021-

Swash Plate Check Valve Pilot Pump Check Valve

22232425-

Pin Pin Link Main Pump

Control by Fan Pump Control Solenoid Valve (Increase of Flow Rate) 1. The fan pump control solenoid valve (12) increases flow rate control pressure Pi according to the signals from MC. 2. Piston (16) moves spool (15) to the right until it balances with the spring force of spring (13). 3. When spool (15) is moved, the large chamber side of servo piston (17) connects to the hydraulic oil tank through the inside of spool (15). 4. Own pump delivery pressure Pd always acts on the small chamber side of servo piston (17) so that servo piston (17) is moved to the left and oil on the large chamber side returns to the hydraulic oil tank. 5. When servo piston (17) is moved, link (24) rotates clockwise by using pin (23) as the supporting point. 6. The end of link (24) is connected to sleeve (14) with pin (22) and sleeve (14) moves to the right. Servo piston (17) moves until the open part between sleeve (14) and spool (15) is closed and stops in the position where the open part is fully closed. 7. As described above, the pump displacement angle increases and the pump delivery flow rate increases. The increased amount of the pump delivery flow rate is proportional to the increased amount of the flow rate control pressure Pi.

TOJBQ40-EN-00(07/02/2020)

T3-1-13

SECTION3 COMPONENT OPERATION Group1 Pump Device Q

Pi TJAQ-03-01-011-1 ja

Q- Flow Rate

Pi- Flow Rate Control Pressure Dr 15

Dr Psv 21 22

19 12

Psv

Pi Pd

15 22 23 24

14 a 20

16 Pd

b 18

25 20 24

17 25

TJAQ-03-01-016-1 ja

Pd- Pump 1 Delivery Pressure Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Psv- Primary Pilot Pressure 111213-

Regulator Fan Pump Control Solenoid Valve Spring

14151617-

a- Displacement Angle Increase b- Displacement Angle Decrease

Sleeve Spool Piston Servo Piston

18192021-

Swash Plate Check Valve Pilot Pump Check Valve

22232425-

Pin Pin Link Main Pump

Control by Fan Pump Control Solenoid Valve (Decrease of Flow Rate) 1. The fan pump control solenoid valve (12) decreases flow rate control pressure Pi according to the signals from MC. 2. Spool (15) moves left until it balances with the spring force of spring (13). 3. When spool (16) is moved, pump delivery pressure Pd is routed through check valve (19), sleeve (14), and spool (15) and acts on the large chamber side of servo piston (17). Own pump delivery pressure Pd also always acts on the small chamber side of servo piston (17) but servo piston (17) moves to the right due to a difference in area. 4. When servo piston (17) is moved, link (24) rotates counterclockwise by using pin (23) as the supporting point.

TOJBQ40-EN-00(07/02/2020)

T3-1-14

SECTION3 COMPONENT OPERATION Group1 Pump Device 5. The end of link (24) is connected to sleeve (14) with pin (22) and sleeve (14) moves to the left. Servo piston (17) moves until the open part between sleeve (14) and spool (15) is closed and stops in the position where the open part is fully closed. 6. As described above, the pump displacement angle decreases and the pump delivery flow rate decreases. The decreased amount of the pump delivery flow rate is proportional to the decreased amount of the flow rate control pressure Pi. Q

Pi TJAQ-03-01-012-1 ja

Q- Flow Rate

Pi- Flow Rate Control Dr 15 Dr

Psv

22 2313 19

Psv

Pi Pd 16

13 16

15 22 23 24

14 a 20

b 18

25 20 18

25 TJAQ-03-01-015-1 ja

Pd- Pump 1 Delivery Pressure Dr- Returning to Hydraulic Oil Tank Pi- Flow Rate Control Pressure Psv- Primary Pilot Pressure 111213-

Regulator Fan Pump Control Solenoid Valve Spring

14151617-

a- Displacement Angle Increase b- Displacement Angle Decrease

Sleeve Spool Piston Servo Piston

18192021-

Swash Plate Check Valve Pilot Pump Check Valve

Outline of Fan Pump Control Solenoid Valve The pump control solenoid valve is installed in the fan pump regulator.

TOJBQ40-EN-00(07/02/2020)

T3-1-15

22232425-

Pin Pin Link Main Pump

SECTION3 COMPONENT OPERATION Group1 Pump Device The pump control solenoid valve controls flow rate control pressure Pi for the regulators according to the signals from MC and increase or decrease the pump delivery flow rate.

Operation of Fan Pump Control Solenoid Valve (When in Neutral) ● Port P (35) and output port (34) are closed by spool (33). Output port (34) and port T (38) are connected by the notch of spool (33). 32

36 35

3334-

Spool Output Port

TJAQ-03-01-009-1 ja 3132-

Spring 1 Spring 2

3536-

Port P Piston

3738-

Solenoid Port T

Operation of Fan Pump Control Solenoid Valve (When Excited) 1. When the signals from MC are received, solenoid (37) is excited and pushes piston (36). 2. Piston (36) shifts spool (33) and the notch of spool (33) connects between port P (35) and output port (34). 3. Therefore, pressure at output port (34) begins to increase. 4. Diameter B is larger than diameter A as for the notch of spool (33). 5. Therefore, when pressure at output port (34) begins to increase, spool (33) moves to the left due to the force as Fsol (39)+P1× A/S1 > P1× B)+S2. 6. When pressure at output port (34) increases and the following formula exists, Fsol (39)+P1× A/S1= P1× B +S2, spool (33) is stopped. P1: Pressure at Output Port (34) A, B: Pressure Receiving Area on Spool (33) S1: Spring 1 (31) Force (Force pushing spool (33) to the left) S2: Spring 2 (32) Force (Force returning spool (33) to the right) Fsol: Solenoid (37) Force

TOJBQ40-EN-00(07/02/2020)

T3-1-16

SECTION3 COMPONENT OPERATION Group1 Pump Device 32

39 36

343536-

Output Port Port P Piston

373839-

TJAQ-03-01-010-1 ja 313233-

Spring 1 Spring 2 Spool

Solenoid Port T Fsol

Outline of Pilot Pump and Oil Cooler Fan Pump The pilot pump and oil cooler fan pump is a gear pump. Drive gear (1) is driven via shaft of the radiator fan pump. Therefore, driven gear (2) engaged with it also rotates. 2

1 a

b T137-02-03-005-1 ja

a- Suction Port 1-

Drive Gear

b- Delivery Port 2-

Driven Gear

Outline of Pump Delivery Pressure Sensor The pump delivery pressure sensor detects the pump delivery pressure, which is used in order to control various operations. When oil pressure is applied to diaphragm (6), diaphragm (6) is deformed. The deformation of diaphragm (6) is detected as electrical signals.

TOJBQ40-EN-00(07/02/2020)

T3-1-17

SECTION3 COMPONENT OPERATION Group1 Pump Device

6 T157-02-03-010-1 ja

34-

Ground Output Signal

Power Source (5 V)

Pressure Receiving Area (Dia phragm)

Outline of Pump Displacement Control Pressure Sensor The pump displacement control pressure sensor detects the pump displacement control pressure, which is used in order to control various operations. When oil pressure is applied to diaphragm (7), diaphragm (7) is deformed. The deformation of diaphragm (6) is detected as electrical signals.

10 T176-03-01-023-1 ja

Pressure Receiving Area (Dia phragm)

TOJBQ40-EN-00(07/02/2020)

89-

Ground Output Signal

10-

T3-1-18

Electric Source (5 V)

SECTION3 COMPONENT OPERATION Group2 Swing Device Outline of Swing Device The swing device consists of valve unit (1), swing motor (2), and swing reduction gear (3). Valve unit (1) prevents the cavitation and the overload in the swing circuit. Swing motor (2) is a swash plate type axial plunger motor (with built-in swing parking brake), which is driven by pressure oil from the pump, and the rotation is transmitted to swing reduction gear (3). Swing reduction gear (3) converts swing motor (2) output into slow large torque to rotate the shaft. Therefore, the upperstructure swings. 1

TJAQ-03-02-001-1 ja 1-

Valve Unit

Swing Motor

Swing Reduction Gear

Outline of Swing Reduction Gear The swing reduction gear is a two-stage planetary reduction gear. Ring gear (4) is installed to housing (11) and is fixed to the upperstructure. Shaft (2) in swing motor (1) rotates first stage sun gear (10), whose rotation power is transmitted to second stage sun gear (8) through first stage planetary gears (3) and first stage carrier (9). Second stage sun gear (8) rotates shaft (6) through second stage planetary gear (5) and second stage carrier (7). Shaft (6) is engaged with the internal gear of the swing bearing which is fixed to the undercarriage and swings the upperstructure.

TOJBQ40-EN-00(07/02/2020)

T3-2-1

SECTION3 COMPONENT OPERATION Group2 Swing Device 1

2 10 9

3 4

5 7

123-

Swing Motor Shaft (Swing Motor) First Stage Planetary Gear

456-

Ring Gear Second Stage Planetary Gear Shaft

789-

Second Stage Carrier Second Stage Sun Gear First Stage Carrier

1011-

TJBQ-03-02-001-1 ja First Stage Sun Gear Housing

Outline of Swing Motor The swing motor consists of swash plate (9), rotor (12), plungers (6), valve plate (13), housing (11), and swing parking brake (14) (springs (1), brake piston (2), plates (3), friction plates (5), and swing parking brake selection valve (4)). Shaft (8) is connected to rotor (12) by a spline joint. Plungers (6) are inserted into rotor (12). When pressure oil is supplied from the pump, plungers (6) are pushed. As swash plate (9) is inclined, shoes (10) on the end of plungers (6) slide along swash plate (9) and rotor (12) rotates. The end of shaft (8) is splined to the first stage sun gear of swing reduction gear. Therefore, the rotation of shaft (8) is transmitted to the swing reduction gear.

TOJBQ40-EN-00(07/02/2020)

T3-2-2

SECTION3 COMPONENT OPERATION Group2 Swing Device

1 13 2 4

14 3 11 10

6 7

8 TJAQ-03-02-003-1 ja 1234-

Spring Brake Piston Plate Swing Parking Brake Selection Valve

TOJBQ40-EN-00(07/02/2020)

56789-

Friction Plate Plunger Retainer Shaft Swash Plate

1011121314-

T3-2-3

Shoe Housing Rotor Valve Plate Swing Parking Brake

SECTION3 COMPONENT OPERATION Group2 Swing Device Outline of Swing Parking Brake The parking brake is a wet-type spring set hydraulic released multi-disc brake. When the brake release pressure moves the piston and pressure oil is routed to brake piston chamber, the brake is released. The brake release pressure flows from the pilot pump only when both swing and front attachments are operated. In other cases (including engine stopping), brake piston chamber is connected to the hydraulic oil tank, and the brake is automatically applied by springs.

When Brake is Released of Swing Parking Brake 1. When the swing and front attachment control levers are operated, the swing parking brake release spool in the signal control valve is shifted. Therefore, pilot pressure from the pilot pump flows to port SH (5). 2. Pilot pressure supplied to port SH (5) opens check valve (4) and acts on brake piston chamber (6). 3. Consequently, as brake piston (2) moves upward, plates (8) and friction plates (7) become free each other so that the brake is released.

1 2

3 10 4

9 123-

Spring Brake Piston Orifice

45-

Check Valve Port SH (Brake Release Pres sure)

678-

Brake Piston Chamber Friction Plate Plate

910-

TJAQ-03-02-004-1 ja Rotor Swing Parking Brake Selection Valve

When Brake is Applied of Swing Parking Brake 1. When the swing and front attachment control levers are returned to the neutral position, the swing parking brake release spool in the signal control valve returns to the neutral. The supply of the pilot pressure to port SH (5) stops. 2. Therefore, check valve (4) is closed and the brake release pressure is released to the swing motor housing through orifice (3). 3. Consequently, the force of springs (1) act on friction plates (7) engaging on the outer circumference of rotor (9) and plates (8) engaging on the inner circumference of the motor housing via brake piston (2). Consequently, the friction

TOJBQ40-EN-00(07/02/2020)

T3-2-4

SECTION3 COMPONENT OPERATION Group2 Swing Device force occurs and the rotor (9) outer circumference is secured. When the engine stops, the brake is automatically applied as pressure is not supplied to port SH (5).

1 2

3 10 4

9 123-

Spring Brake Piston Orifice

45-

Check Valve Port SH (Brake Release Pres sure)

678-

Brake Piston Chamber Friction Plate Plate

910-

TJAQ-03-02-004-1 ja Rotor Swing Parking Brake Selection Valve

Outline of Valve Unit The valve unit consists of the make-up valve and swing relief valve. The make-up valve prevents cavitation in the circuit from occurring. The swing relief valve prevents surge pressure in the circuit from occurring and protects the circuit from being overloaded.

Operation of Make-Up Valve During swing stopping operation, the swing motor is driven by inertial force of the upperstructure. As the swing motor is turned forcibly in excess of oil flow rate from the pump, cavitation occurs in the motor. In order to avoid this cavitation, when the swing circuit pressure becomes lower than pressure in the returning circuit (port M (1)), poppet (8) is opened, hydraulic oil is drawn, and the lack of oil feed is compensated.

TOJBQ40-EN-00(07/02/2020)

T3-2-5

SECTION3 COMPONENT OPERATION Group2 Swing Device

4 1-

Port M

Make-Up Valve

Swing Relief Valve

TJAQ-03-02-005-1 ja Control Valve

7 8

3 TJAQ-03-02-006-1 ja 12-

Port M Make-Up Valve

TOJBQ40-EN-00(07/02/2020)

34-

Swing Relief Valve Control Valve

78-

T3-2-6

Valve Unit Poppet

SECTION3 COMPONENT OPERATION Group2 Swing Device Outline of Swing Relief Valve When starting or stopping swing operation, the swing circuit pressure becomes high. The swing relief valve prevents the circuit pressure from rising higher than the set pressure.

Low-Pressure Relief Operation (Shockless Function) of Swing Relief Valve 1. Pressure at port HP (swing circuit) is routed to oil chamber C (9) through orifice (2) in poppet (1). 2. Pressure oil in chamber C (9) flows to oil chamber A (8) through passage A (4) and flows to oil chamber B (7) through passage B (5). 3. As the pressure receiving area in oil chamber B (7) is larger than the pressure receiving area in oil chamber A (8), piston (6) moves to the left. 4. As long as piston (6) keeps moving, a pressure difference is developed between the front and rear of orifice (2) due to orifice (2). When this pressure difference is increased beyond the spring (3) force, poppet (1) is opened and pressure oil flows to port LP. 5. When piston (6) reaches the stroke end, the pressure difference between the front and rear of orifice (2) disappears and poppet (1) is closed. 1

7 T178-03-02-005-1 ja

HP- Port HP (Swing Circuit) 123-

Poppet Orifice Spring

LP- Port LP (Returning Circuit) 456-

Passage A Passage B Piston

789-

Oil Chamber B Oil Chamber A Oil Chamber C

High-Pressure Relief Operation (Overload Prevention) of Swing Relief Valve 1. After piston (6) reaches the stroke end, the circuit pressure becomes the normal relief set pressure. 2. When pressure at port HP increases further and is beyond the spring (3) set pressure, poppet (1) is opened and pressure oil flows to port LP. 3. When pressure at port HP is decreased to the specified level, poppet (1) is closed by the spring (3) force.

TOJBQ40-EN-00(07/02/2020)

T3-2-7

SECTION3 COMPONENT OPERATION Group2 Swing Device 1

7 T178-03-02-005-1 ja

HP- Port HP (Swing Circuit) 123-

Poppet Orifice Spring

TOJBQ40-EN-00(07/02/2020)

LP- Port LP (Returning Circuit) 456-

Passage A Passage B Piston

789-

T3-2-8

Oil Chamber B Oil Chamber A Oil Chamber C

SECTION3 COMPONENT OPERATION Group3 Control Valve Outline of Control Valve The control valve controls the pressure, flow rate, and flow direction in the hydraulic circuit. The control valve consists of main relief valve(1), overload relief valve, flow combiner valve, anti-drift valve, flow rate control valve, regenerative valve, boom lower meter-in cut valve, auxiliary flow combiner valve, bypass shut-out valve, and spools. The spools are operated by pilot oil pressure. Viewed from the machine front side in the A side block, the spools are arranged as follows: travel (right) (9), bucket (10), boom 1 (8), and arm 2 (11). Viewed from the machine front side in the B side block, the spools are arranged as follows: travel (left) (7), auxiliary (6), boom 2 (4), arm 1 (5), and swing (2) 2 5 4 6 7 1 B

11 8

b A

10 9

Control Valve TJAQ-03-03-001-1 ja

a- Machine Upper Side 124-

Main Relief Valve Swing Boom 2

TOJBQ40-EN-00(07/02/2020)

b- Machine Front Side 567-

Arm 1 Auxiliary Travel (Left)

8910-

T3-3-1

Boom 1 Travel (Right) Bucket Cylinder

11-

Arm 2

SECTION3 COMPONENT OPERATION Group3 Control Valve Components in Control Valve 33

6 4

22 34 35 31

11 12 15

16 20 13 19

28 39 27

23 29

17 TJBQ-03-03-002-1 ja

TOJBQ40-EN-00(07/02/2020)

T3-3-2

SECTION3 COMPONENT OPERATION Group3 Control Valve 123456789-

Check Valve (Main Relief Cir cuit) Main Relief Valve Check Valve (Main Relief Cir cuit) Load Check Valve (Travel (Left) Parallel Circuit) Auxiliary Flow Combiner Valve Check Valve (Bucket Flow Combiner Circuit) Load Check Valve (Bucket Par allel Circuit) Check Valve (Bucket Flow Combiner Circuit) Check Valve (Flow Combiner Circuit)

1011121314151617181920-

Flow Combiner Valve Bucket Regeneration Cut Valve Bucket Regenerative Valve Boom Overload Relief Valve (Boom: Rod Side) Swing Flow Rate Control Valve Overload Relief Valve (Bucket: Rod Side) Overload Relief Valve (Bucket: Bottom Side) Pump 1 Pump 2 Boom Lower Meter-In Cut Valve Boom 2 Anti-Drift Valve

21222324252627282930-

Overload Relief Valve (Boom 1: Bottom Side) Load Check Valve (Travel (Left) Tandem Circuit) Boom 1 Anti-Drift Valve Pump 1 Bypass Shut-Out Valve Boom Flow Rate Control Valve Load Check Valve (Arm 1 Tan dem Circuit) Overload Relief Valve (Arm: Bottom Side) Overload Relief Valve (Arm: Rod Side) Load Check Valve (Arm 2 Tan dem Circuit) Arm Regenerative Cut Valve

313233343536373839-

Load Check Valve (Auxiliary Parallel Circuit) Load Check Valve (Auxiliary Tandem Circuit) Pump 2 Bypass Shut-Out Valve Auxiliary Overload Relief Valve Auxiliary Overload Relief Valve Load Check Valve (Boom 2 Parallel Circuit) Arm 1 Flow Rate Control Valve Arm 2 Flow Rate Control Valve Arm Rod Anti-Drift Valve

A Side X

2 10

21 5

a a

g b

25 15

11 X TJAQ-03-03-003-1 ja

a- Machine Upper Side b- Machine Front Side c- Arm Roll-In Pilot Pressure Sensor d- Bucket Roll-In Pilot Pressure Sensor

e- Bucket Roll-Out Pilot Pressure Sensor f- Arm Roll-Out Pilot Pressure Sensor g- Boom Raise Pilot Pressure Sensor

25-

21-

10-

Main Relief Valve Auxiliary Flow Combiner Valve Flow Combiner Valve

TOJBQ40-EN-00(07/02/2020)

1115-

Bucket Regeneration Cut Valve Overload Relief Valve (Bucket: Rod Side)

23-

T3-3-3

Overload Relief Valve (Boom 1: Bottom Side) Boom 1 Anti-Drift Valve

24253038-

Pump 1 Bypass Shut-Out Valve Boom Flow Rate Control Valve Arm Regenerative Cut Valve Arm 2 Flow Rate Control Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve 33

6 4

22 34 35 31

11 12 15

16 20 13 19

28 39 27

23 29

18 123456789-

TOJBQ40-EN-00(07/02/2020)

1011121314151617181920-

21222324252627282930-

T3-3-4

313233343536373839-

TJBQ-03-03-002-1 ja Load Check Valve (Auxiliary Parallel Circuit) Load Check Valve (Auxiliary Tandem Circuit) Pump 2 Bypass Shut-Out Valve Auxiliary Overload Relief Valve Auxiliary Overload Relief Valve Load Check Valve (Boom 2 Parallel Circuit) Arm 1 Flow Rate Control Valve Arm 2 Flow Rate Control Valve Arm Rod Anti-Drift Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve B Side 34 27 Y

14 37

a b

39 h

33 Y

13 TJBQ-03-03-001-1 ja

a- Machine Upper Side b- Machine Front Side 1314-

Boom Overload Relief Valve (Boom: Rod Side) Swing Flow Rate Control Valve

TOJBQ40-EN-00(07/02/2020)

h- Boom Lower Pilot Pressure Sensor 2027-

Boom 2 Anti-Drift Valve Overload Relief Valve (Arm: Bottom Side)

3334-

T3-3-5

Pump 2 Bypass Shut-Out Valve Auxiliary Overload Relief Valve

3739-

Arm 1 Flow Rate Control Valve Arm Rod Anti-Drift Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve 33

6 4

22 34 35 31

11 12 15

16 20 13 19

28 39 27

23 29

18 123456789-

TOJBQ40-EN-00(07/02/2020)

1011121314151617181920-

21222324252627282930-

T3-3-6

313233343536373839-

SECTION3 COMPONENT OPERATION Group3 Control Valve A-A

b A

b C

24 30

B-B

C-C a

TJAQ-03-03-005-1 ja

a- Machine Upper Side 24-

Pump 1 Bypass Shut-Out Valve

TOJBQ40-EN-00(07/02/2020)

b- Machine Front Side 30-

Arm Regenerative Cut Valve

T3-3-7

SECTION3 COMPONENT OPERATION Group3 Control Valve 33

6 4

22 34 35 31

11 12 15

16 20 13 19

28 39 27

23 29

18 123456789-

TOJBQ40-EN-00(07/02/2020)

1011121314151617181920-

21222324252627282930-

T3-3-8

313233343536373839-

SECTION3 COMPONENT OPERATION Group3 Control Valve D-D

i C

5 14

E-E

F-F

23 j

36 25

37 13 29 26

27 TJAQ-03-03-006-1 ja

a- Machine Upper Side b- Machine Front Side i- Swing j- Arm 2 51314-

Auxiliary Flow Combiner Valve Boom Overload Relief Valve (Boom: Rod Side) Swing Flow Rate Control Valve

TOJBQ40-EN-00(07/02/2020)

k- Arm 1 l- Boom 1 m- Boom 2 20212325-

Boom 2 Anti-Drift Valve Overload Relief Valve (Boom 1: Bottom Side) Boom 1 Anti-Drift Valve Boom Flow Rate Control Valve

262728-

T3-3-9

Load Check Valve (Arm 1 Tan dem Circuit) Overload Relief Valve (Arm: Bottom Side) Overload Relief Valve (Arm: Rod Side)

2936373839-

Load Check Valve (Arm 2 Tan dem Circuit) Load Check Valve (Boom 2 Parallel Circuit) Arm 1 Flow Rate Control Valve Arm 2 Flow Rate Control Valve Arm Rod Anti-Drift Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve 33

6 4

22 34 35 31

11 12 15

16 20 13 19

28 39 27

23 29

18 123456789-

TOJBQ40-EN-00(07/02/2020)

1011121314151617181920-

21222324252627282930-

T3-3-10

313233343536373839-

SECTION3 COMPONENT OPERATION Group3 Control Valve G-G

b A

11 34

31 G

32 12 A

16 a

H-H

I-I

2 p

1 3

33 22 9 10 TJBQ-03-03-003-1 ja

a- Machine Upper Side b- Machine Front Side n- Bucket 12346-

Check Valve (Main Relief Cir cuit) Main Relief Valve Check Valve (Main Relief Cir cuit) Load Check Valve (Travel (Left) Parallel Circuit) Check Valve (Bucket Flow Combiner Circuit)

TOJBQ40-EN-00(07/02/2020)

o- Auxiliary p- Travel (Right) q- Travel (Left) 7891011-

Load Check Valve (Bucket Par allel Circuit) Check Valve (Bucket Flow Combiner Circuit) Check Valve (Flow Combiner Circuit) Flow Combiner Valve Bucket Regeneration Cut Valve

1216223132-

T3-3-11

Bucket Regenerative Valve Overload Relief Valve (Bucket: Bottom Side) Load Check Valve (Travel (Left) Tandem Circuit) Load Check Valve (Auxiliary Parallel Circuit) Load Check Valve (Auxiliary Tandem Circuit)

333435-

Pump 2 Bypass Shut-Out Valve Auxiliary Overload Relief Valve Auxiliary Overload Relief Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve 33

6 4

22 34 35 31

11 12 15

16 20 13 19

28 39 27

23 29

18 123456789-

TOJBQ40-EN-00(07/02/2020)

1011121314151617181920-

21222324252627282930-

T3-3-12

313233343536373839-

SECTION3 COMPONENT OPERATION Group3 Control Valve Main Circuit of Control Valve Pressure oil from pump 1 (21) flows to each spool of travel (right) (4), bucket (5), boom 1 (10), and arm 2 (9) at the 4-spool side of control valve. Pressure oil from pump 2 (19) flows to each spool of swing (15), arm 1 (28), boom 2 (27), auxiliary (23), and travel (left) (18) on the 5-spool side of the control valve. Parallel circuits (8, 25) are provided in each main circuit of pump 1 (21), and pump 2 (19), and make combined operation possible. Flow combiner circuits (2, 17) are provided in both the boom raise and arm circuits, and pressure oil from pump 1 (21), and pump 2 (19) are combined when performing a single operation. Main relief valve (1) is provided in the main circuit (between the pump and the actuator). Main relief valve (1) prevents the pressure in the main circuit from exceeding the set pressure when the spool is operated (or when the control lever is operated). Overload relief valves (7, 12, 13, 22, 29) are provided in the boom, arm, bucket, and auxiliary actuator circuits (between the control valve and the actuator). The overload relief valves (7, 12, 13, 22, 29) prevent surge pressure caused by force in the actuator circuit from exceeding the set pressure when the spool is in neutral (with the control lever set in neutral). Boom overload relief valve (boom: rod side) (20) is provided in the boom lower circuit. Overload Relief Valve (Boom: rod side) (20) lowers the relief set pressure in the boom lower circuit. This reduces vibration of the machine body that occurs during digging and leveling work.

TOJBQ40-EN-00(07/02/2020)

T3-3-13

SECTION3 COMPONENT OPERATION Group3 Control Valve 24

16 13

B A

5 7

22 20 30

31 26

2 17

9 19

123456789-

Main Relief Valve Flow Combiner Circuit (Arm) Travel Motor (Right) Travel (Right) Spool Bucket Spool Bucket Cylinder Overload Relief Valve (Bucket: Rod Side) Parallel Circuit (Pump 1) Arm 2 Spool

1011121314151617-

Boom 1 Spool Boom Cylinder Overload Relief Valve (Boom 1: Bottom Side) Auxiliary Overload Relief Valve Swing Motor Swing Spool Attachment Flow Combiner Circuit (Boom)

1819202122232425-

Travel (Left) Spool Pump 2 Overload Relief Valve (Boom: Rod Side) Pump 1 Auxiliary Overload Relief Valve Auxiliary Spool Travel Motor (Left) Parallel Circuit (Pump 2)

262728293031-

TJBQ-03-03-004-1 ja Arm Cylinder Boom 2 Spool Arm 1 Spool Overload Relief Valve (Arm: Bottom Side) Overload Relief Valve (Bucket: Bottom Side) Overload Relief Valve (Arm: Rod Side)

Pilot Operation Control Circuit of Control Valve Pressure oil (1 to 14) from the pilot valve are routed to the spools in the control valve and move the spools. TOJBQ40-EN-00(07/02/2020)

T3-3-14

SECTION3 COMPONENT OPERATION Group3 Control Valve Pressure oil acts on the following selector valves when performing the following operations. •

When performing arm roll-in (4) operation, pressure oil moves the arm spool and shifts the selector valve spool of the arm rod anti-drift valve (b).

•

When performing boom lower (2) operation, pressure oil moves the boom spool and shifts the selector valve spool of the boom anti-drift valve (c).

•

Air bleed circuit (a) is located in the upper of control valve and bleeds air automatically.

9 10

12 11

13 14

7 8

c a a

1 2 2 1

3 c

4 3

5 6

Pilot Operation Control Circuit TJAQ-03-03-009-1 ja

a- Air Bleed Circuit b- Arm Rod Anti-Drift Valve 1234-

Boom Raise Boom Lower Arm Roll-Out Arm Roll-In

TOJBQ40-EN-00(07/02/2020)

c- Boom Anti-Drift Valve 5678-

Swing Left Swing Right Bucket Roll-In Bucket Roll-Out

9101112-

T3-3-15

Travel Left Forward Travel Left Reverse Travel Right Forward Travel Right Reverse

1314-

Auxiliary Auxiliary

SECTION3 COMPONENT OPERATION Group3 Control Valve External Pilot Pressure Circuit of Control Valve ● The relief pressure of main relief valve (1) is raised by pilot pressure (a) from main relief valve control solenoid valve (SF). ● Boom overload relief valve (4) is shifted by pilot pressure (g) from boom mode selector control solenoid valve (SF). ● Arm 2 flow rate control valve (3) is shifted by pilot pressure (d) from arm 2 flow rate control solenoid valve (SG). ● Arm regeneration cut valve (8) is shifted by pilot pressure (e) from arm regenerative control solenoid valve (SI). ● Swing flow rate control valve (7) is shifted by pilot pressure (f ) from swing flow combiner control solenoid valve (SI). ● Flow combiner valve (2) is shifted by pilot pressure (c) from the flow combiner valve control spool in the signal control valve. ● Pump 1 bypass shut-out valve (5) is shifted by pilot pressure (i) from 4-spool bypass shut-out control solenoid valve (SG). ● Pump 2 Bypass shut-out valve (6) is shifted by pilot pressure (j) from 5-spool bypass shut-out control solenoid valves (SC). 6

1 2

4 g

e i

External Pilot Pressure Circuit TJBQ-03-03-005-1 ja

a- Pilot Pressure from Main Relief Valve Control Solenoid f- Pilot Pressure from Swing Flow Rate Control Solenoid Valve (SF) Valve (SI) c- Pilot Pressure from Flow Combiner Valve Control Spool in g- Pilot Pressure from Boom Mode Selector Control Sole Signal Control Valve noid Valve (SF) d- Pilot Pressure from Arm 2 Flow Rate Control Solenoid i- Pilot Pressure from 4-Spool Bypass Shut-Out Control Sole Valve (SG) noid Valve (SG)

TOJBQ40-EN-00(07/02/2020)

T3-3-16

SECTION3 COMPONENT OPERATION Group3 Control Valve e- Pilot Pressure from Arm Regenerative Control Solenoid Valve (SI)

j- Pilot Pressure from 5-Spool Bypass Shut-Out Control Sole noid Valve (SC)

123-

Main Relief Valve Flow Combiner Valve Arm 2 Flow Rate Control Valve

45-

Boom Overload Relief Valve Pump 1 Bypass Shut-Out Valve

Pump 2 Bypass Shut-Out Valve

78-

Swing Flow Rate Control Valve Arm Regenerative Cut Valve

Operation of Flow Combiner Valve NOTE As an example, the combined operation of travel and boom raise is explained here. 1. When performing combined operation of boom raise and travel, pilot pressure shifts travel (right) spool (5), travel (left) spool (4), boom 1 spool (7), and boom 2 spool (9). 2. At the same time, the travel (right) pilot pressure shifts the flow combiner valve control spool in the signal control valve. 3. Pressure oil from the pilot pump flows to port pH in the flow combiner valve through the flow combiner valve control spool and acts on spool (1). 4. When pressure at port pH increases beyond the spring (2) force, spool (1) compresses spring (2) and moves to the right. 5. Pressure oil from pump 1 (11) flows to travel (right) spool (5). In addition, pressure oil from pump 1 (11) flows to travel (left) spool (4) through spool (1). 6. Pressure oil from pump 2 (10) flows to boom cylinder (8) through boom 2 spool (9) and moves the boom at this time. 7. Consequently, pressure oil from pump 1 (11) is equally supplied to both left and right travel motors, and the machine can travel straight.

TOJBQ40-EN-00(07/02/2020)

T3-3-17

SECTION3 COMPONENT OPERATION Group3 Control Valve

b pH

TJAQ-03-03-012-1 ja

a- Pressure Oil from Pump 1 (11) b- Pilot Pressure from Flow Combiner Valve Control Spool 1-

Spool (Flow Combiner Valve)

TOJBQ40-EN-00(07/02/2020)

c- To Travel (Left) Spool (4)

Spring

T3-3-18

SECTION3 COMPONENT OPERATION Group3 Control Valve 8

B A

9 7

10 11 TJAQ-03-03-011-1 ja

b- Pilot Pressure from Flow Combiner Valve Control Spool 123-

Spool (Flow Combiner Valve) Spring Travel Motor (Left)

TOJBQ40-EN-00(07/02/2020)

456-

Travel (Left) Spool Travel (Right) Spool Travel Motor (Right)

789-

T3-3-19

Boom 1 Spool Boom Cylinder Boom 2 Spool

1011-

Pump 2 Pump 1

SECTION3 COMPONENT OPERATION Group3 Control Valve Outline of Main Relief Valve The main relief valve prevents the pressure in the main circuit from exceeding the set pressure when the actuator such as the motor or the cylinder is operated. Therefore, oil leak from hose and pipe joints and breakage of the actuator are prevented.

Relief Operation of Main Relief Valve 1. Pressure in port HP (main circuit) is routed to pilot poppet (8) through orifice A (2) in main poppet (1) and orifice B (3) in seat (4). 2. When pressure in port HP reaches the set pressure of spring B (6), pilot poppet (8) is opened. Pressure oil from passage A (5) flows along the external circumference of sleeve (11) and flows to port LP (hydraulic oil tank). 3. At this time, a pressure difference is caused between port HP and the spring chamber (10) due to orifice A (2). 4. When the force generated by this pressure difference reaches the set pressure of spring A (9), main poppet (1) is opened and pressure oil from port HP flows to port LP. 5. Consequently, the main circuit pressure decreases. 6. When the main circuit pressure decreases to the specified level, main poppet (1) is closed by the force of spring A (9). Pilot poppet (8) is also closed by the force of spring B (6). 2

When Performing Normal Operation TJAQ-03-03-040-1 ja

HP- Main Circuit 123-

Main Poppet Orifice A Orifice B

TOJBQ40-EN-00(07/02/2020)

LP- Hydraulic Oil Tank 456-

Seat Passage A Spring B

789-

T3-3-20

Piston Pilot Poppet Spring A

1011-

Spring Chamber Sleeve

SECTION3 COMPONENT OPERATION Group3 Control Valve 2

11 1

When Performing Relief Operation TJAQ-03-03-041-1 ja

HP- Main Circuit 123-

LP- Hydraulic Oil Tank

Main Poppet Orifice A Orifice B

456-

Seat Passage A Spring B

789-

Piston Pilot Poppet Spring A

1011-

Spring Chamber Sleeve

Pressure Increasing Operation of Main Relief Valve 1. When performing pressure increasing operation, pilot pressure (PF) from the main relief control solenoid valve acts on piston (7), and spring B (6) is compressed. 2. This increases the force of spring B (6). 3. Consequently, as pressure required in order to open pilot poppet (8) is increased, the relief set pressure is increased. 6

When Performing Pressure-Increase Operation TJAQ-03-03-042-1 ja

HP- Main Circuit LP- Hydraulic Oil Tank 6-

Spring B

TOJBQ40-EN-00(07/02/2020)

PF- Pilot Pressure from Main Relief Control Solenoid Valve 7-

Piston

T3-3-21

Pilot Poppet

SECTION3 COMPONENT OPERATION Group3 Control Valve Outline of Overload Relief Valve (With Make-Up Function) The overload relief valves are provided in the boom, arm, bucket, and auxiliary circuits. The overload relief valve prevents the pressure in each actuator circuit from exceeding the set pressure when the actuators are moved by external force. In addition, when the actuator circuit pressure decreases, the overload relief valve draws hydraulic oil from the hydraulic oil tank and prevents the occurrence of cavitation (make-up function).

Relief Operation of Overload Relief Valve 1. Pressure in port HP (actuator circuit) acts on pilot poppet (8) through orifice (11) of piston (10). 2. When pressure in port HP reaches the set pressure of spring B (6), pilot poppet (8) is opened, pressure oil from passage A (5) flows along the outer circumference of sleeve (3), and flows to port LP (hydraulic oil tank). 3. At this time, a pressure difference occurs between port HP and spring chamber (9) due to orifice (11). 4. When the force generated by this pressure difference reaches the set pressure of spring A (4), piston (10) and main poppet (2) are opened and pressure oil from port HP flows to port LP. 5. Consequently, the actuator circuit pressure decreases. 6. When the actuator circuit pressure decreases to the specified level, piston (10) and main poppet (2) are closed by the force of spring A (4). Pilot poppet (8) is also closed by the force of spring B (6). 2

LP 11

When Performing Normal Operation T107-02-05-019-1 ja

HP- Actuator Circuit 234-

Main Poppet Sleeve Spring A

TOJBQ40-EN-00(07/02/2020)

LP- Hydraulic Oil Tank 567-

Passage A Spring B Spring C

8910-

T3-3-22

Pilot Poppet Spring Chamber Piston

11-

Orifice

SECTION3 COMPONENT OPERATION Group3 Control Valve 2

LP 11

When Performing Relief Operation T178-03-03-049-1 ja

HP- Actuator Circuit 234-

LP- Hydraulic Oil Tank

Main Poppet Sleeve Spring A

567-

Passage A Spring B Spring C

8910-

Pilot Poppet Spring Chamber Piston

11-

Orifice

Make-Up Operation of Overload Relief Valve 1. When pressure in port HP (actuator circuit) decreases lower than pressure in port LP (hydraulic oil tank), sleeve (3) is moved to the right. 2. Hydraulic oil in port LP flows to port HP and cavitation is prevented. 3. When pressure in port HP increases to the specified pressure, sleeve (3) is closed by the force of spring C (7). 3

LP 7

When Performing Make-Up Operation T178-03-03-050-1 ja

HP- Actuator Circuit 3-

Sleeve

LP- Hydraulic Oil Tank 7-

Spring C

Outline of Boom Overload Relief Valve (Low Pressure) A boom overload relief valve (low pressure) is provided in the boom lower circuit. The boom overload relief valve (low pressure) is shifted by pilot pressure from boom mode selector control solenoid valve (SF) and relieves the boom cylinder rod-side circuit at low pressure. This reduces vibration of the machine body during digging work.

TOJBQ40-EN-00(07/02/2020)

T3-3-23

SECTION3 COMPONENT OPERATION Group3 Control Valve Relief Operation of Boom Overload Relief Valve (Low Pressure) 1. Pressure in port HP (actuator circuit) acts on pilot poppet (8) through orifice (11) of piston (10). 2. When pilot pressure from boom mode selector control solenoid valve (SF) acts, it moves piston (pilot) (1) to the left. 3. When pressure in port HP reaches the set pressure of spring B (6), pilot poppet (8) is opened, pressure oil from passage A (5) flows along the outer circumference of sleeve (3), and flows to port LP (hydraulic oil tank). 4. At this time, a pressure difference occurs between port HP and spring chamber (9) due to orifice (11). 5. When the force generated by this pressure difference reaches the set pressure of spring A (4), piston (10) and main poppet (2) are opened and pressure oil from port HP flows to port LP. 6. Consequently, pressure on the boom cylinder rod side decreases, and vibration of the machine is reduced when performing digging work. 7. When the pressure on the boom cylinder rod side decreases to the specified level, piston (10) and main poppet (2) are closed by the force of spring A (4). Pilot poppet (8) is also closed by the force of spring B (6). 3

When Performing Normal Operation TJAQ-03-03-038-1 ja

HP- Actuator Circuit 123-

LP- Hydraulic Oil Tank

Piston (Pilot) Main Poppet Sleeve

456-

Spring A Passage A Spring B

789-

SF- Pilot Pressure from Boom Mode Se lector Control Solenoid Valve Spring C Pilot Poppet Spring Chamber

1011-

Piston (Main) Orifice

When Performing Relief Operation TJAQ-03-03-039-1 ja

HP- Actuator Circuit 123-

Piston (Pilot) Main Poppet Sleeve

TOJBQ40-EN-00(07/02/2020)

LP- Hydraulic Oil Tank 456-

Spring A Passage A Spring B

789-

T3-3-24

SF- Pilot Pressure from Boom Mode Se lector Control Solenoid Valve Spring C Pilot Poppet Spring Chamber

1011-

Piston (Main) Orifice

SECTION3 COMPONENT OPERATION Group3 Control Valve Make-Up Operation of Boom Overload Relief Valve (Low Pressure) 1. When pressure in port HP (actuator circuit) decreases lower than pressure in port LP (hydraulic oil tank), sleeve (3) is moved to the right. 2. Hydraulic oil in port LP flows to port HP and cavitation is prevented. 3. When pressure in port HP increases to the specified pressure, sleeve (3) closes. 3 LP

When Performing Make-Up Operation TJAQ-03-03-043-1 ja

HP- Actuator Circuit 3-

LP- Hydraulic Oil Tank

Sleeve

TOJBQ40-EN-00(07/02/2020)

T3-3-25

SECTION3 COMPONENT OPERATION Group3 Control Valve Outline of Regenerative Valve The regenerative valves are provided in the boom lower, arm roll-in, and bucket roll-in circuits. The regenerative valves increase cylinder speed, improve machine controllability, and prevent cylinder hesitation.

Operation of Boom Regenerative Valve 1. When performing boom lower operation with the front attachment above the ground, returning oil from the boom cylinder (2) bottom side shifts boom lower meter-in cut valve (1). As a result, the supply of pressure oil from the pump to boom 1 spool (3) stops. (Refer to "Outline of Boom Lower Meter-In Cut Valve"T3-3-40.) 2. At this time, when pressure in the boom cylinder (2) rod side is lower than the bottom side, check valve (4) is opened. 3. Consequently, returning oil from the boom cylinder (2) bottom side is supplied to the rod side and the regenerative operation is done. 4. When boom cylinder (2) reaches the stroke end or digging loads increase, pressure in the boom cylinder (2) rod side circuit is higher than the bottom side. 5. Therefore, check valve (4) of the boom regenerative valve is closed and regenerative operation is stopped.

TOJBQ40-EN-00(07/02/2020)

T3-3-26

SECTION3 COMPONENT OPERATION Group3 Control Valve 2

5 1 4 3

TJAQ-03-03-017-1 ja

a- Boom Lower Pilot Pressure 1-

Boom Lower Meter-In Cut Valve

TOJBQ40-EN-00(07/02/2020)

23-

Boom Cylinder Boom 1 Spool

45-

T3-3-27

Check Valve Boom 2 Spool

SECTION3 COMPONENT OPERATION Group3 Control Valve a

3 5 6

When Performing Boom Regenerative Operation TJAQ-03-03-018-1 ja

a- Boom Lower Pilot Pressure c- Returning Oil from Boom Cylinder (2) Bottom Side

d- Pressure Oil to Boom Cylinder (2) Rod Side

Boom 1 Spool

Check Valve

Boom 2 Spool

Hole

Outline of Bucket Regenerative Valve The bucket regenerative valve supplys returning oil of the bucket cylinder rod side to the bottom side, prevent cylinder hesitation, and increase bucket roll-in operating speed when performing bucket roll-in operation.

Operation When Performing Bucket Regenerative Operation 1. Returning oil from the bucket cylinder (1) rod side is routed to check valve (2) through hole (4) of bucket spool (3) when performing bucket roll-in operation. 2. At this time, when pressure in the bucket cylinder (1) bottom side is lower than the rod side, check valve (2) is opened. 3. Consequently, returning oil from the bucket cylinder (1) rod side flows to the bottom side and is combined with pressure oil from pump 1. The combined pressure oil is delivered to the bucket cylinder (1) bottom side and regenerative operation is done. 4. Therefore, cylinder hesitation is prevented and bucket roll-in operating speed increases during bucket roll-in operation.

TOJBQ40-EN-00(07/02/2020)

T3-3-28

SECTION3 COMPONENT OPERATION Group3 Control Valve 1 a

2 TJAQ-03-03-013-1 ja

a- Pressure Oil from Pump 1 1-

Bucket Cylinder

Check Valve

Bucket Spool

4 b

When Performing Bucket Regenerative Operation TJAQ-03-03-014-1 ja

b- Returning Oil from Bucket Cylinder (1) Rod Side

c- Pressure Oil to Bucket Cylinder (1) Bottom Side

Check Valve

Bucket Spool

Hole

Operation When Performing Bucket Regenerative Cut Operation 1. When bucket cylinder (3) reaches the stroke end or digging loads increase when performing bucket roll-in operation, pressure in the bucket cylinder (3) bottom side increases. At this time, pressure oil from pump 1 acts on spool (1) of the bucket regeneration cut valve. 2. Spool (1) compresses spring (2) and moves upward (to the right in the circuit diagram). 3. Pressure in the cylinder (3) rod side is lower than the bucket cylinder (3) bottom side. As check valve (4) of the bucket regenerative valve is kept closed and pressure oil from the bucket cylinder (3) rod side does not flow to the bucket cylinder (3) bottom side, regenerative operation is not done. 4. Pressure oil from the cylinder (3) rod side flows to the hydraulic oil tank through bucket spool (5) and spool (1). 5. Therefore, the pressure at bucket cylinder (3) rod side decreases and the digging force is improved.

TOJBQ40-EN-00(07/02/2020)

T3-3-29

SECTION3 COMPONENT OPERATION Group3 Control Valve a

b 1

4 TJAQ-03-03-015-1 ja

a- Pressure Oil from Pump 1 1-

Spool (Bucket Regeneration Cut Valve)

b- To Hydraulic Oil Tank 23-

Spring Bucket Cylinder

45-

Check Valve Bucket Spool

2 1 5

When Performing Bucket Regeneration Cut Operation TJAQ-03-03-016-1 ja

a- Pressure Oil from Pump 1 b- To Hydraulic Oil Tank 1-

Spool (Bucket Regeneration Cut Valve)

c- Returning Oil from Bucket Cylinder (3) Rod Side d- Pressure Oil to Bucket Cylinder (3) Bottom Side 24-

Spring Check Valve

56-

Bucket Spool Hole

Orifice

Operation When Performing Arm Regenerative Operation 1. When performing arm roll-in operation, the returning oil from arm cylinder (5) rod side acts on check valve (7) through hole (8) of arm 1 spool (1). 2. At this time, when pressure in the arm cylinder (5) bottom side is lower than the rod side, check valve (7) opens. 3. Due to orifice (3) of arm regenerative cut valve (4), pressure is generated at the cylinder port. 4. Consequently, the returning oil from the arm cylinder (5) rod side is combined with pressure oil (a) from pump 1. The combined pressure oil is delivered to the arm cylinder (5) bottom side.

TOJBQ40-EN-00(07/02/2020)

T3-3-30

SECTION3 COMPONENT OPERATION Group3 Control Valve 5. Therefore, regenerative operation is done. When performing arm roll-in operation, arm hesitation is prevented, and the arm roll-in speed increases. 1 5

7 b

4 3 2 TJAQ-03-03-032-1 ja

a- Pressure Oil from Pump 1 12-

Arm 1 Spool Pump 2

TOJBQ40-EN-00(07/02/2020)

b- Arm Roll-In Pilot Pressure 34-

Orifice Arm Regenerative Cut Valve

57-

T3-3-31

Arm Cylinder Check Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve

8 6

TJAQ-03-03-033-1 ja

c- Returning Oil from Arm Cylinder (5) Rod Side d- Pressure Oil to Arm Cylinder (5) Bottom Side 16-

Arm 1 Spool Spool (Arm Regenerative Cut Valve)

78-

Check Valve Hole

Operation When Performing Arm Regenerative Cut Operation When performing arm roll-in operation, spool (6) in arm regenerative cut valve is shifted according to other operating conditions and working conditions, and controls the appropriate operation according to the pump load. 1. When arm regenerative control solenoid valve (SI) is activated by the signal from MC (main controller), spool (6) of the arm regenerative valve is shifted by pilot pressure. (Refer to SYSTEM/Control System.) 2. Pressure oil from the arm cylinder (5) rod side flows to the hydraulic oil tank through spool (6). TOJBQ40-EN-00(07/02/2020)

T3-3-32

SECTION3 COMPONENT OPERATION Group3 Control Valve 3. Therefore, the pressure at arm cylinder (5) rod side decreases and the digging force is improved. 5

6 4

2 TJAQ-03-03-030-1 ja

b- Arm Roll-In Pilot Pressure 12-

Arm 1 Spool Pump 2

TOJBQ40-EN-00(07/02/2020)

e- Pilot Pressure from Arm Regenerative Control Valve 45-

Arm Regenerative Cut Valve Arm Cylinder

T3-3-33

Spool (Arm Regenerative Cut Valve)

SECTION3 COMPONENT OPERATION Group3 Control Valve e

TJAQ-03-03-031-1 ja

c- Returning Oil from Arm Cylinder (5) Rod Side e- Pilot Pressure from Solenoid Valve Unit (SC) 6-

Spool (Arm Regenerative Cut Valve)

TOJBQ40-EN-00(07/02/2020)

T3-3-34

SECTION3 COMPONENT OPERATION Group3 Control Valve Outline of Anti-Drift Valve Anti-drift valves are provided in the circuits of the boom cylinder bottom side and arm cylinder rod side, and reduce the cylinder drift.

NOTE Both boom and arm anti-drift valves are identical in structure.

Holding Operation of Anti-Drift Valve 1. As pressure oil from the pilot valve does not flow with the control lever set in neutral (the spool in neutral), the selector valve (3) in anti-drift valve is not shifted. 2. Pressure in arm cylinder (1) rod side (boom cylinder bottom side) acts on check valve (2) (spring (4) side) in the antidrift valve through selector valve (3). 3. Consequently, as check valve (2) is pushed and the return circuit from boom cylinder (1) is blocked, the boom cylinder (1) drift is reduced. 1

TJAQ-03-03-019-1 ja 1-

Arm Cylinder

Check Valve (Anti-Drift Valve)

Selector Valve (Anti-Drift Valve)

3 d TJAQ-03-03-020-1 ja

d- Returning Oil from Cylinder (1) (Arm Cylinder: Rod Side, Boom Cylinder: Bottom Side)

e- To Main Spool

Check Valve (Anti-Drift Valve)

TOJBQ40-EN-00(07/02/2020)

Selector Valve (Anti-Drift Valve)

T3-3-35

Spring

SECTION3 COMPONENT OPERATION Group3 Control Valve Releasing Operation of Anti-Drift Valve 1. Pressure oil from the pilot valve shifts selector valve (3) when performing arm roll-in or boom lower operation. 2. Pressure oil in the spring (4) chamber of check valve (2) is returned to the hydraulic oil tank through the passage of selector valve (3). 3. When the pressure in spring (4) chamber decreases, pressure from arm cylinder (1) rod side (boom cylinder bottom side) moves check valve (2) to the right (left in the circuit diagram). 4. Consequently, returning oil from the arm cylinder (1) rod side (boom cylinder bottom side) flows to the spool. 5. Orifice (5) causes the pressure in the spring (4) chamber to decrease slowly. Therefore, check valve (2) is prevented from moving quickly, and shock when performing arm roll-in or boom lower operation is reduced. 3

a TJAQ-03-03-025-1 ja

a- Pressure Oil from Pump 2 b- To Hydraulic Oil Tank 1-

Arm Cylinder

c- Pressure Oil from Pilot Valve 2-

Check Valve (Anti-Drift Valve)

Selector Valve (Anti-Drift Valve)

4 5

3 TJAQ-03-03-026-1 ja

c- Pressure Oil from Pilot Valve d- Returning Oil from Cylinder (Arm Cylinder: Rod Side, Boom Cylinder: Bottom Side)

e- To Main Spool

Check Valve

Selector Valve

Spring

Orifice

Outline of Flow Rate Control Valve Flow rate control valves are provided in the arm 1, arm 2, boom 1, and swing circuits. They restrict oil flow rate in the circuit when performing combined operation, giving priority to other actuators. TOJBQ40-EN-00(07/02/2020)

T3-3-36

SECTION3 COMPONENT OPERATION Group3 Control Valve Each flow rate control valve is operated when performing combined operation as shown in the table. Flow Rate Control Valve

Combined Operation

Arm 1

Swing, Arm Roll-In

Arm 2

Boom Raise, Arm Roll-In Boom Raise, Arm Roll-Out

Boom 1

Boom Lower (With Front Attachment Above Ground (Bottom Side High Pressure))

Swing

Swing, Boom Raise Swing, Arm Roll-Out

Normal Operation of Flow Rate Control Valve NOTE As an example, the arm 1 flow rate control valve is explained here. 1. Pressure oil from pump 2 (a) acts on check valve (4) of poppet valve (3). 2. Normally, as selector valve (2) is kept open, pressure oil (a) from pump 2 opens check valve (4) and flows to the arm 1 spool through selector valve (2). 3. When load in the actuator side is high, poppet valve (3) is opened and pressure oil (a) from pump 2 flows to the arm 1 spool. 4. Flow rate flowing to the arm 1 spool increases and arm operating speed becomes fast. 1

3 a

2 TJAQ-03-03-021-1 ja

a- Pressure Oil from Pump 2 1-

Arm Cylinder

TOJBQ40-EN-00(07/02/2020)

Selector Valve

T3-3-37

Poppet Valve

Check Valve

SECTION3 COMPONENT OPERATION Group3 Control Valve 2

4 3

When Performing Normal Operation TJAQ-03-03-022-1 ja

a- Pressure Oil from Pump 2 b- To Arm 1 Spool 2-

Selector Valve

c- To Hydraulic Oil Tank 3-

Poppet Valve

Check Valve

Flow Rate Control Operation of Flow Rate Control Valve NOTE As an example, the arm 1 flow rate control valve is explained here. 1. Selector valve (2) of the arm 1 flow rate control valve is shifted by pilot pressure (d) from the arm flow rate control valve control spool inside the signal control valve. 2. Back pressure in poppet valve (3) increases and the force to close poppet valve (3) appears. 3. The opening clearance of poppet valve (3) is reduced and pressure oil flow rate flowing to the arm 1 spool is restricted. 4. Pressure oil from pump 2 flows preferentially to the boom 2 spool.

TOJBQ40-EN-00(07/02/2020)

T3-3-38

SECTION3 COMPONENT OPERATION Group3 Control Valve 1

d a

2 TJAQ-03-03-023-1 ja

a- Pressure Oil from Pump 2 1-

Arm Cylinder

d- Pilot Pressure from Arm Flow Rate Control Valve Control Spool in Signal Control Valve 2-

Selector Valve

Poppet Valve c

When Performing Flow Rate Control Operation TJAQ-03-03-024-1 ja

a- Pressure Oil from Pump 2 b- To Arm 1 Spool 2-

Selector Valve

TOJBQ40-EN-00(07/02/2020)

c- To Hydraulic Oil Tank d- Pilot Pressure from Arm Flow Rate Control Valve Control Spool in Signal Control Valve 3-

Poppet Valve

T3-3-39

SECTION3 COMPONENT OPERATION Group3 Control Valve Outline of Boom Lower Meter-In Cut Valve The boom lower meter-in cut valve is provided in the boom lower circuit. Boom lower meter-in cut control is deactivated when the track raised off the ground, and the boom is given priority to operate and jack-up force increases. When performing boom lower operation above ground, the boom lowers under its own weight due to the regenerative circuit of boom 1 spool (6). This allows pressure oil from the pump to flow to other actuators. Consequently, operating speed of other actuator increases. (Refer to SYSTEM/Hydraulic System.)

TOJBQ40-EN-00(07/02/2020)

T3-3-40

SECTION3 COMPONENT OPERATION Group3 Control Valve NOTE The illustration shows when performing combined operation of boom lower with front attachment above the ground and arm roll-out. 4

15 B A

2 7

10 TJAQ-03-03-027-1 ja

b- Boom Lower Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

T3-3-41

SECTION3 COMPONENT OPERATION Group3 Control Valve 123-

Arm 2 Spool Spool (Boom Lower Meter-In Cut Valve) Boom Flow Rate Control Valve (Selector Valve)

4678-

Boom Cylinder Boom 1 Spool Boom 2 Spool Pump 2

9101314-

Boom Flow Rate Control Valve (Poppet Valve) Pump 1 Arm Cylinder Arm 1 Spool

151617-

Orifice Spring Port 4Pc11

Operation of Boom Lower Meter-In Cut Valve (With the Track off the Ground) 1. As pressure at the boom cylinder (4) bottom side decreases with the track raised off the ground, pressure which acts on spool (2) decreases. 2. When pressure from the boom cylinder (4) bottom side is larger than the spring (16) force, boom lower meter-in cut valve (2) moves to the left (upward in circuit diagram) due to the spring (16) force. 3. As boom lower pilot pressure (b) is not acting on boom flow rate control valve (selector valve) (3), boom flow rate control valve (poppet valve) (9) opens. 4. Pressure oil from pump 1 (10) flows through boom 1 spool (6). 5. Therefore, boom lower meter-in cut control is not operated with the track raised off the ground. (Refer to SYSTEM/ Hydraulic System.) 16 b

2 d

15 TJAQ-03-03-028-1 ja

a- To 4Pj2 Port b- Boom Lower Pilot Pressure 2-

Spool (Boom Lower Meter-In Cut Valve)

TOJBQ40-EN-00(07/02/2020)

c- Pressure Oil from Boom Cylinder (4) Bottom Side d- To Hydraulic Oil Tank 1516-

Orifice Spring

T3-3-42

SECTION3 COMPONENT OPERATION Group3 Control Valve NOTE The diagram shows combined operation of boom lower with track raised off the ground and arm roll-out. 4

15 B A

10 TJAQ-03-03-049-1 ja

b- Boom Lower Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

T3-3-43

SECTION3 COMPONENT OPERATION Group3 Control Valve 124-

Arm 2 Spool Spool (Boom Lower Meter-In Cut Valve) Boom Cylinder

67810-

Boom 1 Spool Boom 2 Spool Pump 2 Pump 1

13141516-

Arm Cylinder Arm 1 Spool Orifice Spring

17-

Port 4Pc11

Operation of Boom Lower Meter-In Cut Valve (With the Front Attachment above the Ground) 1. When boom lower operation is performed, pilot pressure acts on boom 1 spool (6) and boom 2 spool (7). 2. Returning oil from the boom cylinder (4) bottom side is divided into two directions. 3. One acts on spool (2) through orifice (15). When pressure from the boom cylinder (4) bottom side exceeds the spring (16) force, spool (2) compresses spring (16) and moves to the left (downward in circuit diagram). 4. Pressure oil from port 4Pc11 (17) passes through spool (2) and acts on boom flow rate control valve (selector valve) (3), closing boom flow rate control valve (poppet valve) (9). This restricts the flow rate of pressure oil from pump 1 (10) to boom 1 spool (6). (Refer to the flow rate control valve.) 5. The other flow of pressure oil flows through boom 2 spool (7) and returns to the hydraulic oil tank. 6. This causes the boom to lower due to own weight. 7. When performing combined operation of boom lower and other actuator, more pressure oil is supplied to the other actuator, and speed of actuator increases.

TOJBQ40-EN-00(07/02/2020)

T3-3-44

SECTION3 COMPONENT OPERATION Group3 Control Valve 16 b

2 d

15 TJAQ-03-03-028-2 ja

a- To 4Pj2 Port b- Boom Lower Pilot Pressure 2-

Spool (Boom Lower Meter-In Cut Valve)

TOJBQ40-EN-00(07/02/2020)

c- Pressure Oil from Boom Cylinder (4) Bottom Side d- To Hydraulic Oil Tank 1516-

Orifice Spring

T3-3-45

SECTION3 COMPONENT OPERATION Group3 Control Valve NOTE The diagram shows boom lower operation with front attachment above the ground. 4

15 B A

2 7

17 13

10 TJAQ-03-03-029-1 ja

b- Boom Lower Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

T3-3-46

SECTION3 COMPONENT OPERATION Group3 Control Valve 123-

Arm 2 Spool Spool (Boom Lower Meter-In Cut Valve) Boom Flow Rate Control Valve (Selector Valve)

467810-

Boom Cylinder Boom 1 Spool Boom 2 Spool Pump 2 Pump 1

1314151617-

Arm Cylinder Arm 1 Spool Orifice Spring Port 4Pc11

Operation of Auxiliary Flow Combiner Valve (Auxiliary Flow Combiner Valve: OFF) The auxiliary flow combiner valve (1) combines pressure oil from both pump 1 (6) and pump 2 (5) when performing attachment (2) operation. Therefore, the attachment (2) operating speed increases. 1. Pressure oil from pump 1 (a) acts on check valve (2) of poppet valve (3). 2. Normally, as selector valve (1) is kept open, pressure oil (a) from pump 1 presses open check valve (2) and flows to poppet valve (3) through selector valve (1). 3. Pressure oil from selector valve (1) increases the back pressure in poppet valve (3) increases, producing a force acting to close poppet valve (3). 4. The opening clearance of poppet valve (3) is reduced, and the flow rate of pressure oil flowing to auxiliary spool (5) is restricted. 4 5 1

2 3 c

a TJAQ-03-03-045-1 ja

a- Pressure Oil from Pump 1 12-

Selector Valve Check Valve

TOJBQ40-EN-00(07/02/2020)

c- Pressure Oil from Pump 2 34-

Poppet Valve Attachment

T3-3-47

Auxiliary Spool

SECTION3 COMPONENT OPERATION Group3 Control Valve 1 a

5 TJAQ-03-03-048-1 ja

a- To Hydraulic Oil Tank 1-

Selector Valve

b- Pilot Pressure from Auxiliary Flow Combiner Control Sole noid Valve (SA) 3-

Poppet Valve

Auxiliary Spool

Operation of Auxiliary Flow Combiner Valve (Auxiliary Flow Combiner Valve: ON) 1. Selector valve (1) of the auxiliary flow combiner valve is shifted by pilot pressure (b) from the attachment selector valve. 2. Back pressure in poppet valve (3) decreases, reducing the force acting to close poppet valve (3). 3. The opening clearance of poppet valve (3) increases, increasing the flow rate of pressure oil flowing from pump 1 to auxiliary spool (5). 4. Pressure oil (a) from pump 1 is combined with pressure oil (c) from pump 2, increasing the operating speed of attachment (4).

TOJBQ40-EN-00(07/02/2020)

T3-3-48

SECTION3 COMPONENT OPERATION Group3 Control Valve 4 5 1

b 2 3 c

a TJAQ-03-03-046-1 ja

a- Pressure Oil from Pump 1 b- Pilot Pressure from Attachment Selector Valve

c- Pressure Oil from Pump 2

12-

Selector Valve Check Valve

34-

Poppet Valve Attachment

Auxiliary Spool

1 a

TJAQ-03-03-047-1 ja

a- To Hydraulic Oil Tank 1-

Selector Valve

b- Pilot Pressure from Attachment Selector Valve 3-

Poppet Valve

Outline of Pump 1 Bypass Shut-Out Valve and Pump 2 Bypass Shut-Out Valve Pump 1 bypass shut-out valve (2) is provided downstream of the neutral circuit on pump 1 (1) side. Pump 2 bypass shutout valve (4) is provided downstream of the neutral circuit on pump 2 (3) side.

TOJBQ40-EN-00(07/02/2020)

T3-3-49

SECTION3 COMPONENT OPERATION Group3 Control Valve As the neutral circuits on the control valve 4-spool side and 5-spool side are blocked, pump 1 bypass shut-out valve (2) and pump 2 bypass shut-out valve (4) increase the amount of oil flowing to the cylinders, increasing the cylinder operating speed. When it is necessary to raise the exhaust temperature in order to regenerate the aftertreatment device, as the neutral circuits on the control valve 4-spool side and 5-spool side are blocked, pump 1 bypass shut-out valve (2) and pump 2 bypass shut-out valve (4) raise the pressure of pump 1 (1) and pump 2 (3), applying a load to the engine and raising the exhaust temperature. 4

1 TJAQ-03-03-044-1 ja

12-

Pump 1 Pump 1 Bypass Shut-Out Valve

TOJBQ40-EN-00(07/02/2020)

34-

Pump 2 Pump 2 Bypass Shut-Out Valve

T3-3-50

SECTION3 COMPONENT OPERATION Group3 Control Valve Operation of Pump 1 Bypass Shut-Out Valve 1. When operating attachment (2), attachment pilot pressure acts on ports 4Pj1, 4Pj2, and 4Pc4, and auxiliary flow combiner valve (1) and spool (3) in the pump 1 bypass shut-out valve are shifted. 2. When spool (3) in the pump 1 bypass shut-out valve is shifted, the neutral circuit in pump 1 (6) side is blocked. 3. At this time, as spool (1) in the auxiliary flow combiner valve is also shifted, pressure oil in pump 1 (6) flows to auxiliary spool (7) through the auxiliary flow combiner valve. 4. Consequently, pressure oil in both pump 1 (6) and pump 2 (5) are combined and operating speed of attachment (2) increases. 3

a, b

TJAQ-03-03-035-1 ja

a- Pilot Pressure from Port 4Pj1 3-

b- Pilot Pressure from Port 4Pj2

Spool (Pump 1 Bypass ShutOut Valve)

TOJBQ40-EN-00(07/02/2020)

T3-3-51

SECTION3 COMPONENT OPERATION Group3 Control Valve

2 B A

c a b

3 TJBQ-03-03-006-1 ja

a- Pilot Pressure from Port 4Pj1 12-

Spool (Auxiliary Flow Combiner Valve) Attachment

TOJBQ40-EN-00(07/02/2020)

34-

b- Pilot Pressure from Port 4Pj2 Spool (Pump 1 Bypass ShutOut Valve) Attachment Selector Valve

567-

T3-3-52

Pump 2 Pump 1 Auxiliary Spool

c- Pilot Pressure from Port 4Pc4 8-

Poppet (Auxiliary Flow Combiner Valve)

SECTION3 COMPONENT OPERATION Group3 Control Valve Operation of Pump 2 Bypass Shut-Out Valve 1. When 5-spool bypass shut-out control solenoid valve (SC) (1) is activated by the signal from MC, pilot pressure shifts pump 2 bypass shut-out valve (5). 2. Spool (5) compresses spring (6) and moves to the left. 3. The pump 2 neutral circuit (c) is blocked by spool (5), and pressure oil from pump 2 is combined with pressure oil from pump 1. 4. Therefore, the bucket operating speed increases.

5 c b

a TJAQ-03-03-037-1 ja

a- Pilot Pressure from 5-Spool Bypass Shut-Out Control Sole c- To Hydraulic Oil Tank noid Valve (SC) b- Pump 2 Neutral Circuit 5-

Spool (Pump 2 Bypass ShutOut Valve)

TOJBQ40-EN-00(07/02/2020)

Spring

T3-3-53

SECTION3 COMPONENT OPERATION Group3 Control Valve 2

4 TJAQ-03-03-036-1 ja

a- Pilot Pressure from 5-Spool Bypass Shut-Out Control Sole noid Valve (SC) 1-

5-Spool Bypass Shut-Out Con trol Solenoid Valve (SC)

TOJBQ40-EN-00(07/02/2020)

23-

Bucket Spool Pump 2

T3-3-54

Pump 1

Spool (Pump 2 Bypass ShutOut Valve)

SECTION3 COMPONENT OPERATION Group4 Pilot Valve Outline of Pilot Valve The pilot valve controls pilot pressure oil in order to move the spool in the control valve. The pilot valve outputs pressure according to the control lever stroke by PPC (Pressure Proportional Control) function. The 4-port pilot valves for front attachment/swing and for travel are standard. In addition, the 2-port pilot valve is for auxiliary (Option).

Outline of Front Attachment/Swing Pilot Valve Port No. Right

Left

Hitachi Pattern

Bucket Roll-Out

←

Boom Lower

←

Bucket Roll-In

←

Boom Raise

←

Swing (Right)

Arm Roll-In

Arm Roll-Out

Swing (Right)

Swing (Left)

Arm Roll-Out

Arm Roll-In

Swing (Left)

ISO Control Pattern

3 2

3 1

TDFY-03-04-001-1 ja

P- Port P (Pressure Oil from Pilot Pump)

T- Port T (To Hydraulic Oil Tank)

Port 1

TOJBQ40-EN-00(07/02/2020)

Port 2

T3-4-1

Port 3

Port 4

SECTION3 COMPONENT OPERATION Group4 Pilot Valve Outline of Travel Pilot Valve Port No. 1

Travel (Right Reverse)

Travel (Right Forward)

Travel (Left Forward)

Travel (Left Reverse) P

T 1

2 3

1 TDC1-03-04-008-1 ja

P- Port P (Pressure Oil from Pilot Pump) 1-

Port 1

T- Port T (To Hydraulic Oil Tank) 2-

Port 2

Port 3

Outline of Auxiliary Pilot Valve Port No. Auxiliary

TOJBQ40-EN-00(07/02/2020)

Open

T3-4-2

Port 4

SECTION3 COMPONENT OPERATION Group4 Pilot Valve P

P 1

2 TDC1-03-04-009-1 ja

P- Port P (Pressure Oil from Pilot Pump) 1-

Port 1

T- Port T (To Hydraulic Oil Tank) 2-

Port 2

Operation of Front Attachment/Swing and Travel Pilot Valves The spool (7) head is hanged from the upper surface of spring guide (4). Spring guide (4) is kept raised by return spring (6).

NOTE Total lever strokes for front attachment/swing controls are determined by stroke dimension (E) of pusher (2). Total lever stroke for travel control is determined by stroke dimension (E) of cam (1).

TOJBQ40-EN-00(07/02/2020)

T3-4-3

SECTION3 COMPONENT OPERATION Group4 Pilot Valve X

1 E

2 3 4

3 4

5 5 6 6

8 7 8

TDFY-03-04-002-1 ja

X- Front Attachment/Swing Pilot Valve

Y- Travel Pilot Valve

12-

56-

Cam Pusher

34-

Casing Spring Guide

Balance Spring Return Spring

78-

Spool Hole

When Front Attachment/Swing and Travel Pilot Valves are in Neutral (Output Curve: A to B) 1. When in neutral, spool (7) completely blocks pressure oil from port P (pilot pump). The output port is connected to port T (hydraulic oil tank) through the inner passage in spool (7). 2. Therefore, pressure in the output port is equal to pressure in port T. 3. When the control lever is slightly tilted, cam (1) is tilted and pusher (2) is pushed downward. Pusher (2) integral with spring guide (4) compresses return spring (6) and moves downward. 4. At this time, as pressure in the output port is equal to pressure in port T, spool (7) moves downward due to the balance spring (5) force while keeping the lower surface of the spool (7) head in contact with spring guide (4). 5. This status continues until hole (8) on spool (7) is connected to port P. E

T523-02-05-001 ja

a- Pilot Pressure TOJBQ40-EN-00(07/02/2020)

b- Lever Stroke

T3-4-4

SECTION3 COMPONENT OPERATION Group4 Pilot Valve X

X 1

7 T

8 P

Y 1

2 T

3 3

d T

7 P

TDFY-03-04-003-1 ja

X- Front Attachment/Swing Pilot Valve Y- Travel Pilot Valve P- Port P

T- Port T d- Output Port

12-

56-

Cam Pusher

TOJBQ40-EN-00(07/02/2020)

34-

Casing Spring Guide

T3-4-5

Balance Spring Return Spring

78-

Spool Hole

SECTION3 COMPONENT OPERATION Group4 Pilot Valve During Metering or Decompressing of Front Attachment/Swing and Travel Pilot Valves (Output Curve: C to D) 1. When the control lever is further tilted and pusher (2) is moved downward further, hole (8) on spool (7) is connected to port P and pressure oil in port P flows to the output port. 2. Pressure in the output port acts on the bottom surface of spool (7) and spool (7) is pushed upward. 3. When the force to move spool (7) upward is smaller than the balance spring (5) force, balance spring (5) is not compressed and spool (7) is not raised and pressure in the output port increases. 4. Pressure in the output port increases further, the force to move spool (7) upward increases. When this force overcomes the balance spring (5) force, spool (7) compresses balance spring (5) and moves upward. 5. When spool (7) is moved upward, hole (8) is closed and pressure oil does not flow from port P to the output port. Therefore, pressure in the output port stops increasing. 6. When spool (7) is moved downward, balance spring (5) is compressed same as spool (7) movement. The spring force balances with the force which pressure acts on the spool, and its pressure is the output port pressure. E

T523-02-05-001 ja

a- Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

b- Lever Stroke

T3-4-6

SECTION3 COMPONENT OPERATION Group4 Pilot Valve X

X 1

4 8

5 6

6 P

2 T

7 3 P

4 8

6 a

7 P

8 d

d TDFY-03-04-004-1 ja

X- Front Attachment/Swing Pilot Valve Y- Travel Pilot Valve P- Port P

T- Port T d- Output Port

12-

56-

Cam Pusher

TOJBQ40-EN-00(07/02/2020)

34-

Casing Spring Guide

T3-4-7

Balance Spring Return Spring

78-

Spool Hole

SECTION3 COMPONENT OPERATION Group4 Pilot Valve Full Stroke of Front Attachment/Swing and Travel Pilot Valves (Output Curve: E to F) 1. (Front Attachment/Swing Pilot Valve) When control lever is set to the full stroke, pusher (2) moves downward until it comes in contact with the stepped part of casing (3). (Travel Pilot Valve) When control lever is set to the full stroke, cam (1) moves downward until it comes in contact with casing (3). 2. At this time, the bottom surface of pusher (2) directly pushes spool (7). Therefore, even if pressure in the output port increases further, hole (8) on spool (7) is kept open. 3. Consequently, pressure in the output port is equal to pressure in port P. E

T523-02-05-001 ja

a- Pilot Pressure

b- Lever Stroke

Y 1 1 2

2 3 3 4

T P T

8 d

d TDFY-03-04-005-1 ja

X- Front Attachment/Swing Pilot Valve Y- Travel Pilot Valve P- Port P TOJBQ40-EN-00(07/02/2020)

T- Port T d- Output Port

T3-4-8

SECTION3 COMPONENT OPERATION Group4 Pilot Valve 12-

Cam Pusher

34-

Casing Spring Guide

56-

Balance Spring Return Spring

78-

Spool Hole

Operation of Auxiliary Pilot Valve The spool (7) head is hanged from the upper surface of spring guide (4). Spring guide (4) is kept raised by return spring (6).

NOTE The total lever stroke for auxiliary is determined by stroke dimension (E) of cam (1). E 1

2 3

4 5

6 7 8

TDAA-03-04-001-1 ja 12-

Cam Pusher

34-

Plate Spring Guide

56-

Balance Spring Return Spring

78-

Spool Hole

When Auxiliary Pilot Valve are in Neutral (Output Curve: A to B) 1. When the control pedal is in neutral, spool (7) completely blocks pressure oil from port P. The output port is connected to port T (hydraulic oil tank) through the inner passage in spool (7). 2. Therefore, pressure in the output port is equal to pressure in port T. 3. When the control pedal is slightly depressed, cam (1) is moved and pusher (2) is pushed downward. Pusher (2) integral with spring guide (4) compresses return spring (6) and moves downward. 4. At this time, as pressure in the output port is equal to pressure in port T, spool (7) moves downward due to the balance spring (5) force while keeping the lower surface of the spool (7) head in contact with spring guide (4). 5. This status continues until hole (8) on spool (7) is connected to port P.

NOTE The pusher stroke provided until hole (8) in spool (7) is connected to port P is play of the control pedal.

TOJBQ40-EN-00(07/02/2020)

T3-4-9

SECTION3 COMPONENT OPERATION Group4 Pilot Valve

a D

T1F3-03-09-004 ja

a- Pilot Pressure

b- Pusher Stroke

1 7

8 P 3

4 5

6 7

8 8 d

TDC1-03-04-014-2 ja

P- Port P T- Port T 12-

Cam Pusher

d- Output Port 34-

Plate Spring Guide

56-

Balance Spring Return Spring

78-

Spool Hole

During Metering or Decompressing of Auxiliary Pilot Valve (Output Curve: C to D) 1. When the control pedal is further depressed and pusher (2) is moved downward further, hole (8) on spool (7) is connected to port P and pressure oil in port P flows to the output port. 2. Pressure in the output port acts on the bottom surface of spool (7) and spool (7) is pushed upward. 3. When the force to move spool (7) upward is smaller than the balance spring (5) force, balance spring (5) is not compressed and spool (7) is not raised and pressure in the output port increases. 4. Pressure in the output port increases further, the force to move spool (7) upward increases. When this force overcomes the balance spring (5) force, spool (7) compresses balance spring (5) and moves upward. 5. When spool (7) is moved upward, hole (8) is closed and pressure oil does not flow from port P to the output port. Therefore, pressure in the output port stops increasing.

TOJBQ40-EN-00(07/02/2020)

T3-4-10

SECTION3 COMPONENT OPERATION Group4 Pilot Valve 6. When spool (7) is moved downward, balance spring (5) is compressed same as spool (7) movement. The spring force balances with the force which pressure acts on the spool, and its pressure is the output port pressure. a D

T1F3-03-09-004 ja

a- Pilot Pressure

b- Pusher Stroke

1 7

8 P

4 T

6 7

4 T

6 7

8 d

d TDC1-03-04-015-2 ja

P- Port P T- Port T 12-

Cam Pusher

TOJBQ40-EN-00(07/02/2020)

d- Output Port 34-

Plate Spring Guide

56-

T3-4-11

Balance Spring Return Spring

78-

Spool Hole

SECTION3 COMPONENT OPERATION Group4 Pilot Valve Outline of Shockless Function (Only Travel Pilot Valve) The travel pilot valve has damper (1) enabling damping of the speed change shock by travel control lever (4). Damper (1) is consist of support (5), gear 1 (9), gear 2 (8), and others. Gear 1 (9) is connected to support (5). Support (5) is secure to bracket (6) by spring pin (2). Travel control lever (4) and travel pedal (3) are secure to bracket (6). Therefore, support (5) rotates to the left and right around pin (7) according to movement of travel control lever (4). 1

A-A

4 5 1 5 6 7 8 9 A

TDC1-03-04-016-1 ja 123-

Damper Spring Pin Travel Pedal

456-

Travel Control Lever Support Bracket

789-

Pin Gear 2 Gear 1

Operation of Shockless Function 1. If travel control lever (4) is released while traveling, spring force of the return spring returns travel control lever (4) to the neutral position. 2. At this time, gear 1 (9) and gear 2 (8) inside damper (1) receive resistance force due to friction. 3. Consequently, as travel control lever (4) gradually returns to the neutral position, the extent of sudden stop at the time of abrupt release of travel control lever (4) is reduced.

TOJBQ40-EN-00(07/02/2020)

T3-4-12

SECTION3 COMPONENT OPERATION Group4 Pilot Valve 1

A-A

4 5 1 5 6 7 8 9 A

TDC1-03-04-016-1 ja 123-

Damper Spring Pin Travel Pedal

TOJBQ40-EN-00(07/02/2020)

456-

Travel Control Lever Support Bracket

789-

T3-4-13

Pin Gear 2 Gear 1

SECTION3 COMPONENT OPERATION Group4 Pilot Valve MEMO

TOJBQ40-EN-00(07/02/2020)

T3-4-14

SECTION3 COMPONENT OPERATION Group5 Travel Device Outline of Travel Device The travel device consists of travel motor (4), travel reduction gear (2), and travel brake valve (1). Travel motor (4) is a swash plate type variable displacement axial plunger motor and equipped with a parking brake (a wet-type spring set hydraulic released multi-disc brake). Travel motor (4) is driven by pressure oil from the pump and transmits the rotation power to travel reduction gear (2). Travel reduction gear (2) is a three-stage planetary reduction gear, converts the travel motor (4) rotation power to a slowlarge torque, and rotates sprocket (3) and the track link. Travel brake valve (1) protects the travel circuit from being overloaded and prevents the occurrence of cavitation. 1

4 1-

Travel Brake Valve

TOJBQ40-EN-00(07/02/2020)

Travel Reduction Gear

T3-5-1

Sprocket

WJBQ-04-02-002-2 ja Travel Motor

SECTION3 COMPONENT OPERATION Group5 Travel Device Outline of Travel Reduction Gear The travel reduction gear is a three-stage planetary reduction gear. The travel motor rotates propeller shaft (7). This rotation is transmitted to ring gear (1) through first stage planetary gears (8), first stage carrier (6), second stage sun gear (5), second stage planetary gears (9), second stage carrier (4), third stage sun gear (3), third stage planetary gears (10), and third stage carrier (2). Housing (14) of the travel motor is secured to the track frame with bolts. In addition, housing (14) supports drum (13) via bearings (15) so that drum (13) can rotate. Third stage carrier (2) is connected to housing (14) by a spline joint. Ring gear (1), drum (13), and sprocket (12) are secured with bolts. Therefore, when ring gear (1) rotates, drum (13) and sprocket (12) also rotate. 14

11 13 2 3

9 10

12 WJBQ-04-02-002-3 ja 1234-

Ring Gear Third Stage Carrier Third Stage Sun Gear Second Stage Carrier

TOJBQ40-EN-00(07/02/2020)

5678-

Second Stage Sun Gear First Stage Carrier Propeller Shaft First Stage Planetary Gear

9101112-

T3-5-2

Second Stage Planetary Gear Third Stage Planetary Gear Bearing Nut Sprocket

131415-

Drum Housing Bearing

SECTION3 COMPONENT OPERATION Group5 Travel Device Outline of Travel Motor The travel motor is a swash plate type variable displacement axial plunger motor, and consists of parts including valve plate (6), swash plate (4), rotor (2), plungers (5), and shaft (1). Shaft (1) is connected to rotor (2) by a spline joint. Plungers (5) are inserted into rotor (2). When pressure oil is supplied from the pump, plungers (5) are pushed. As swash plate (4) is inclined, shoes (3) on the end of plungers (5) slide along swash plate (4) and rotor (2) rotates. 2

5 TJBQ-03-05-001-1 ja

12-

Shaft Rotor

34-

Shoe Swash Plate

56-

Plunger Valve Plate

Operation of Travel Motor 1. Pressure oil flows to port B in valve plate (6), enters one side in rotor (2), and pushes plungers (5). 2. Shoes (3) at the ends of plungers (5) slide on swash plate (4) due to this force, and rotates rotor (2) and output shaft (1). 3. As rotor (2) rotates, plungers (5) rotates.When plungers (5) reach port A, plungers (5) are pushed back and pressure oil is returned to the hydraulic oil tank. 4. Whether forward travel or reverse travel depends on whether pressure oil is supplied to port A or port B.

TOJBQ40-EN-00(07/02/2020)

T3-5-3

SECTION3 COMPONENT OPERATION Group5 Travel Device A

A B

6 2 5

6 T183-03-05-009-2 ja

A- Port A (Pressure oil from main pump or returning oil to hydraulic oil tank)

B- Port B (Pressure oil from main pump or returning oil to hydraulic oil tank)

12-

56-

Shaft Rotor

34-

Shoe Swash Plate

Plunger Valve Plate

Outline of Parking Brake The parking brake is a wet-type spring set hydraulic released multi-disc brake. The brake is released when the brake release pressure is routed to brake piston chamber (a) to move brake piston (5). The parking brake is automatically applied at all times unless the travel function is operated. Friction plates (2) and plates (3) are connected to housing (1) of the travel motor and rotor (4) by a spline joint respectively.

TOJBQ40-EN-00(07/02/2020)

T3-5-4

SECTION3 COMPONENT OPERATION Group5 Travel Device 1

2 6

TJAQ-03-05-001-1 ja

P1- Port P1 (Pressure Oil from Main Pump) P2- Port P2 (Pressure Oil from Main Pump)

a- Brake Piston Chamber b- To Brake Piston

12-

56-

Housing Friction Plate

34-

Plate Rotor

Brake Piston Spring

Counterbalance Valve Spool

Operation of Parking Brake (When Parking Brake is Released) 1. When the travel control lever is operated, pressure oil from the main pump flows to port P1 or P2 in the travel motor through the control valve. 2. This pressure oil shifts counterbalance valve spool (7) in the travel brake valve and acts on brake piston (5) through the notch on counterbalance valve spool (7). 3. Consequently, as brake piston (5) is pushed, plates (3) and friction plates (2) become freed each other so that the brake is released.

TOJBQ40-EN-00(07/02/2020)

T3-5-5

SECTION3 COMPONENT OPERATION Group5 Travel Device 1

2 6

TJAQ-03-05-003-1 ja

P1- Port P1 (Pressure Oil from Main Pump) P2- Port P2 (Pressure Oil from Main Pump)

a- Brake Piston Chamber b- To Brake Piston

12-

56-

Housing Friction Plate

34-

Plate Rotor

Brake Piston Spring

Counterbalance Valve Spool

Operation of Parking Brake (When Parking Brake is Applied) 1. When the travel control lever is returned to neutral, counterbalance valve spool (7) in the travel brake valve is returned to neutral. 2. As pressure oil routed to brake piston (5) is returned to the drain circuit, brake piston (5) is returned by spring (6). 3. Consequently, the spring force acts on plates (3), which are engaged with the outer circumference of rotor (4), and on friction plates (2), which are engaged with the inside of housing (1) of the travel motor, through brake piston (5). Therefore, the outer circumference of rotor (4) is secured with friction force.

TOJBQ40-EN-00(07/02/2020)

T3-5-6

SECTION3 COMPONENT OPERATION Group5 Travel Device 1

TJAQ-03-05-002-1 ja

P1- Port P1 (Pressure Oil from Main Pump) P2- Port P2 (Pressure Oil from Main Pump)

a- Brake Piston Chamber b- To Brake Piston

12-

56-

Housing Friction Plate

34-

Plate Rotor

Brake Piston Spring

Counterbalance Valve Spool

Outline of Travel Brake Valve The travel brake valve is located on the travel motor head and consists of the following valves. •

Counterbalance valve (2): Counterbalance valve (2) ensures smooth start/stop travel operation and prevents rollaway when descending a slope. In addition, counterbalance valve (2) routes the travel motor operating pressure oil in highpressure port (P1 or P2) to the parking brake.

•

Check valve (3): Check valve (3) assists the operation of counterbalance valve (2) and prevents cavitation in the motor circuit.

•

Travel relief valve (1): Travel relief valve (1) prevents the occurrence of overload and surge pressure in the motor circuit and reduces shock loads developed when stopping travel operation.

•

Travel motor displacement angle control valve (4): The travel motor displacement angle control valve (4) shifts the spool by pilot pressure from the travel motor displacement angle control solenoid valve (SC), and delivers pressure oil from the control valve to the piston.

TOJBQ40-EN-00(07/02/2020)

T3-5-7

SECTION3 COMPONENT OPERATION Group5 Travel Device A-A 2

4 P1

3 P2

2 1 TJAQ-03-05-004-1 ja

P1- Port P1 12-

Travel Relief Valve Counterbalance Valve

P2- Port P2 3-

Check Valve

Travel Motor Displacement Angle Control Valve

Operation of Counterbalance Valve (During Travel) 1. When pressure oil from the control valve enters port P1 (6), pressure oil flows around the outer circumference of spool (4), unseats check valve BM (12), and flows to motor port BM (11). 2. On the other hand, returning oil from the travel motor is returned to motor port AM (10). However, its passage is blocked by check valve AM (7) and spool (4). 3. When pressure in port P1 (6) increases further, pressure oil from port P1 (6) is routed through oil passage F (c) in spool (4), and it unseats the check valve (spool) (3) in spool (4) and flows to chamber G (a). In addition, pressure oil from port P1 (6) flows to chamber G (a) through orifice (2) and orifice A (1) in spool (4). Therefore, spool (4) moves downward. 4. Consequently, returning oil from the travel motor flows to port P2 (8) through notch (g) on spool (4). As pressure oil starts flowing at this stage, the travel motor starts rotating. 5. When the travel control lever is returned to neutral, spool (4) is returned to the original position by the spring force and blocks the oil passage. Then, the travel motor rotation is stopped.

TOJBQ40-EN-00(07/02/2020)

T3-5-8

SECTION3 COMPONENT OPERATION Group5 Travel Device a

1 2 6 b

b c d

8 4 g

5 10

TJAQ-03-05-005-1 ja

a- Chamber G b- From Port P1 c- Oil Passage F d- To Port P2 123-

Orifice A Orifice Check Valve (Spool)

e- From Port AM f- To Port BM g- Notch 456-

Spool Spring Port P1

789-

Check Valve AM Port P2 Counterbalance Valve

101112-

Port AM Port BM Check Valve BM

Operation of Counterbalance Valve (When Descending a Slope) 1. When the machine descends a slope, the travel motors are forcibly rotated by the machine self weight like a pump. 2. If the travel motor draws oil, oil pressure in port P1 (6) and chamber G (a) decreases. Spool (4) moves upward and restricts returning oil from the travel motor. 3. Therefore, oil pressure in motor port AM (10) increases and functions as the brake of the travel motor. 4. When pressure in port P1 (6) increases again, spool (4) moves downward. 5. The machine descends the slope with spool (4) in the position where pressure in port P1 (6) balances with pressure at the motor port AM (10) side. 6. Therefore, the hydraulic brake is applied and prevents the machine from rollaway.

TOJBQ40-EN-00(07/02/2020)

T3-5-9

SECTION3 COMPONENT OPERATION Group5 Travel Device a

6 4

b f

8 e

TJAQ-03-05-006-1 ja

a- Chamber G b- From Port P1 c- Oil Passage F d- To Port P2 123-

Orifice A Orifice Check Valve (Spool)

TOJBQ40-EN-00(07/02/2020)

e- From Port AM f- To Port BM g- Notch 456-

Spool Spring Port P1

789-

T3-5-10

Check Valve AM Port P2 Counterbalance Valve

101112-

Port AM Port BM Check Valve BM

SECTION3 COMPONENT OPERATION Group5 Travel Device Outline of Travel Relief Valve When the travel motor circuit pressure increases beyond the set pressure, the travel relief valve is opened and high pressure oil is relieved to the low-pressure side. Therefore, the travel motor is protected from being overloaded. In addition, the overload relief valve relieves the shock loads developed due to inertia force when stopping the travel motor. When the travel motor draws pressure oil like a pump, check valve is unseated (make-up operation) and prevents the cavitation.

Operation of Travel Relief Valve (During Relief) 1. Pressure oil in the travel circuit acts on poppet (6) through motor port P1 (or motor port P2). 2. Pressure oil flows to the spring (2) chamber through orifice (5) in poppet (6). 3. Pressure oil flowing to the spring (2) chamber acts on piston (4) through orifice (3) and moves piston (4) downward. 4. As long as piston (4) keeps moving, a pressure difference is developed between the front and rear of poppet (6). When this pressure difference is increased beyond the spring (2) force, poppet (6) is opened and pressure oil flows to the hydraulic oil tank. 5. When piston (4) reaches the stroke end, the pressure difference between the front and rear of poppet (6) disappears and poppet (6) is closed. 6. Under this condition, the pressure in the travel motor circuit increases to the relief set pressure. 7. When the pressure in the travel motor circuit increases beyond the spring (2) force, poppet (6) is opened and pressure oil at the relief set pressure flows to the hydraulic oil tank. 8. As described above, relief operation in two-stages prevents the travel motor from being overloaded and reduces shocks developed in the circuit when stopping the travel motor. 1 2 3 4 5 6 b

a TJAQ-03-05-007-1 ja

a- From Motor Port P1 and P2 12-

Relief Valve Spring

b- To Hydraulic Oil Tank 34-

Orifice Piston

56-

Orifice Poppet

Operation of Travel Relief Valve (During Make-Up) 1. When the machine descends a slope, the travel motors are forcibly rotated by the machine self weight like a pump. 2. When pressure in the motor port BM (7) (or motor port AM (6)) circuit becomes lower than pressure in port P1 (3) (or port P2 (4)), check valve (2) opens to draw hydraulic oil, compensating the lack of oil feed.

TOJBQ40-EN-00(07/02/2020)

T3-5-11

SECTION3 COMPONENT OPERATION Group5 Travel Device 1

2 7

4 5

12-

Relief Valve Check Valve

TOJBQ40-EN-00(07/02/2020)

34-

Port P1 Port P2

56-

T3-5-12

Relief Valve Motor Port AM

TJAQ-03-05-008-1 ja Motor Port BM

SECTION3 COMPONENT OPERATION Group5 Travel Device Outline of Travel Mode Control The displacement angle of swash plate is changed by piston movement and shift the travel mode.

Operation of Selecting Travel Mode (Slow Speed) 1. When the travel mode switch is in the slow speed position, MC (main controller) does not send signals to the travel motor displacement angle control solenoid valve (SC). Therefore, pilot port (4) of the travel motor displacement angle control valve (3) is connected to the hydraulic oil tank. Then, spool (5) of the travel motor displacement angle control valve (3) is pushed to the left by spring (6). 2. As pressure oil from motor port (P1 (1) or P2 (2)) at the high-pressure side does not act on piston (7), the displacement angle is held to the maximum. Consequently, the stroke of plunger (9) is longer and the travel motor rotates at slow speed. 8

4 5

1, 2

TJAQ-03-05-009-1 ja 123-

Motor Port P1 Motor Port P2 Travel Motor Displacement Angle Control Valve

4567-

Pilot Port Spool Spring Piston

8910-

Orifice (For Slow/Fast Speed) Plunger Swash Plate

Operation of Selecting Travel Mode (Fast Speed) 1. When the travel mode switch is set to the fast speed position, MC (main controller) sends signals to the travel motor displacement angle control solenoid valve (SC) in response to travel loads. (Refer to "Travel Motor Displacement Angle Control"T2-2-58.) 2. Pilot pressure is supplied from pilot port (4) of the travel motor displacement angle control valve (3) and moves spool (5) to the right. 3. Pressure oil (b) from the high-pressure side of motor port (P1 (1) or P2 (2)) flows through the inner passage of the travel motor, spool (5), and orifice (8). Pressure oil flowing through orifice (8) gradually acts on piston (7). 4. Therefore, piston (7) pushes swash plate (10) and the displacement angle of swash plate (10) is reduced. As the stroke of plungers (9) will be shorter, the travel motor rotates at fast speed. TOJBQ40-EN-00(07/02/2020)

T3-5-13

SECTION3 COMPONENT OPERATION Group5 Travel Device 8

4 5

1, 2

TJAQ-03-05-010-1 ja

b- Pressure Oil 123-

Motor Port P1 Motor Port P2 Travel Motor Displacement Angle Control Valve

TOJBQ40-EN-00(07/02/2020)

4567-

Pilot Port Spool Spring Piston

8910-

T3-5-14

Orifice (For Slow/Fast Speed) Plunger Swash Plate

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve Outline of Signal Control Valve The signal control valve is provided in the pilot circuit between the pilot valve and the control valve, and controls various signal pressure used to regulate the pumps and valves. The signal control valve consists of the shuttle valves, shockless valve (1), pump 1 flow rate control valve (3), pump 2 flow rate control valve (6), flow combiner valve control spool (4), arm flow rate control valve control spool (2), and swing parking brake release spool (5). A A-A A

TJAQ-05-04-007-2 ja

a- Pilot Valve Side 12-

Shockless Valve Arm Flow Rate Control Valve Control Spool

Pump 1 Flow Rate Control Valve

45-

Flow Combiner Valve Control Spool Swing Parking Brake Release Spool

67-

Pump 2 Flow Rate Control Valve Auxiliary

Pilot Valve Side of Pilot Port Port Name

Connection

Remarks

Port A

Pilot Valve (Right)

Boom Raise Pilot Pressure

Port B

Pilot Valve (Right)

Boom Lower Pilot Pressure

Port C

Pilot Valve (Left)

Arm Roll-Out Pilot Pressure

Port D

Pilot Valve (Left)

Arm Roll-In Pilot Pressure

Port E

Pilot Valve (Left)

Swing (Left) Pilot Pressure

Port F

Pilot Valve (Left)

Swing (Right) Pilot Pressure

Port G

Pilot Valve (Right)

Bucket Roll-In Pilot Pressure

Port H

Pilot Valve (Right)

Bucket Roll-Out Pilot Pressure

Port I

Travel Pilot Valve

Travel (Left Forward) Pilot Pressure

Port J

Travel Pilot Valve

Travel (Left Reverse) Pilot Pressure

Port K

Travel Pilot Valve

Travel (Right Forward) Pilot Pressure

Port L

Travel Pilot Valve

Travel (Right Reverse) Pilot Pressure

Port M

Auxiliary Pilot Valve

Auxiliary Open Pilot Pressure

Port N

Auxiliary Pilot Valve

Auxiliary Close Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

T3-6-1

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve Port Name

Connection

Remarks

Port SA

4-Spool Pilot Pressure Sensor

Pump 1 Delivery Flow Rate Control

Port SB

5-Spool Pilot Pressure Sensor

Pump 2 Delivery Flow Rate Control

Port PI

Pilot Shut-off Solenoid Valve

Primary Pilot Pressure

Port SH

Swing Parking Brake

Brake Release Pressure

Port DF

Hydraulic Oil Tank

Returning to Hydraulic Oil Tank A

E M D B H

SB G

N SA I

PI K

J SH DF

Pilot Valve Side TJAQ-03-06-001-1 ja

Control Valve Side of Pilot Port Port Name

Connection

Remarks

Port 1

Control Valve

Boom Raise Pilot Pressure

Port 2

Control Valve

Boom Lower Pilot Pressure

Port 3

Control Valve

Arm Roll-Out Pilot Pressure

Port 4

Control Valve

Arm Roll-In Pilot Pressure

Port 5

Control Valve

Swing (Left) Pilot Pressure

Port 6

Control Valve

Swing (Right) Pilot Pressure

Port 7

Control Valve

Bucket Roll-In Pilot Pressure

Port 8

Control Valve

Bucket Roll-Out Pilot Pressure

Port 9

Control Valve

Travel (Left Forward) Pilot Pressure

Port 10

Control Valve

Travel (Left Reverse) Pilot Pressure

Port 11

Control Valve

Travel (Right Forward) Pilot Pressure

TOJBQ40-EN-00(07/02/2020)

T3-6-2

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve Port Name

Connection

Remarks

Port 12

Control Valve

Travel (Right Reverse) Pilot Pressure

Port 13

Control Valve

Auxiliary Open Pilot Pressure

Port 14

Control Valve

Auxiliary Close Pilot Pressure

Port SE

Control Valve

Arm 1 Flow Rate Control Valve Control Pressure

Port SM

Attachment Pilot Pressure Sensor (Option)

Port SN

Plug

Port SP

Hydraulic Oil Tank

Returning to Hydraulic Oil Tank

Port SL

Control Valve

Flow Combiner Valve Control Pressure

Port SK

Plug

Port S3

Swing Pilot Pressure Sensor

Port TR

Travel Pilot Pressure Sensor

13 5 4 SK

14 6 7 9 SN

10 11

SL TR

Control Valve Side TJAQ-03-06-002-1 ja

Outline of Shuttle Valve The shuttle valve selects pilot pressure used to perform each operation and routes pilot pressure to the corresponding control valves and/or control spools. The spools corresponding to each operation are shown in the table: Arm Flow Rate Control Valve Flow Combiner Valve Control Swing Parking Brake Release Control Spool Spool Spool Boom Raise TOJBQ40-EN-00(07/02/2020)

T3-6-3

○

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve Boom Lower

○

Arm Roll-Out

○

Arm Roll-In

○

Bucket Roll-In

○

Bucket Roll-Out

○

Swing Right

○

Swing Left

○

Travel (Right)

○

Travel (Left)

Auxiliary Open

○

Auxiliary Close

○

2 4

15 16

i l

9 m

12 10 11

7 TJAQ-03-06-003-1 ja

a- Travel (Left) b- Travel (Right) c- Swing d- Arm e- Boom f- Bucket g- Auxiliary

TOJBQ40-EN-00(07/02/2020)

h- Swing Parking Brake Release Spool i- Arm Flow Rate Control Valve Control Spool j- Shockless Valve k- Flow Combiner Valve Control Spool l- Pump 2 Flow Rate Control Valve m- Pump 1 Flow Rate Control Valve

T3-6-4

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve 12345-

Boom, Arm, Bucket, Travel (Right) Travel (Left) Travel (Left), Travel (Right) Travel (Right) Boom Cylinder

678910-

Arm Cylinder Boom, Arm, Swing, Auxiliary Boom Raise, Arm Boom, Arm Boom, Arm, Bucket

111213-

Boom, Arm, Bucket, Swing, Auxiliary Boom, Arm, Bucket, Travel (Left) Boom, Arm, Bucket, Travel (Swing Left), Swing

14151617-

Bucket Cylinder Swing Auxiliary Swing, Auxiliary

A-A A

8 5

6 9

17 16 15 7 10

12 a

TJAQ-03-06-004-1 ja

a- Pilot Valve Side 12345-

Boom, Arm, Bucket, Travel (Right) Travel (Left) Travel (Left), Travel (Right) Travel (Right) Boom Cylinder

TOJBQ40-EN-00(07/02/2020)

678910-

Arm Cylinder Boom, Arm, Swing, Auxiliary Boom Raise, Arm Boom, Arm Boom, Arm, Bucket

111213-

T3-6-5

Boom, Arm, Bucket, Swing, Auxiliary Boom, Arm, Bucket, Travel (Left) Boom, Arm, Bucket, Travel (Swing Left), Swing

14151617-

Bucket Cylinder Swing Auxiliary Swing, Auxiliary

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve Outline of Shockless Valve The shockless valve is provided in the boom raise circuit and functions during boom lowering operation or when stopping boom raise operation.

Operation of Shockless Valve (During Boom Raise Operation) 1. Boom raise pilot pressure is routed to spool (1) through port A (2). 2. Immediately after operation is started, the pilot pressure is low. The low pilot pressure is routed to the spring B (3) chamber through clearance C between spool (1) and housing (7) and inner passage 3 (9). The pilot pressure is also routed to the port 1 (4) side through inner passage 2 (5) at the same time. 3. When pilot pressure increases, pressure in the spring B (3) chamber also increases. Spool (1) pushes spring A (6) and is moved to the left. 4. As spool (1) is moved, port A (2) is connected to port 1 (4) and pressure in the port 1 (4) side increases. Then, the control valve spool is moved. 1

5 4

4 TDC1-03-06-004-1 ja 12-

Spool Port A

TOJBQ40-EN-00(07/02/2020)

34-

Spring B Port 1

56-

T3-6-6

Inner Passage 2 Spring A

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve 6

2 C

3 1

4 2

During Boom Raise Operation TDC1-03-06-005-1 ja 12-

Spool Port A

34-

Spring B Port 1

56-

Inner Passage 2 Spring A

Housing

Operation of Shockless Valve (During Boom Lower Operation or When Stopping Boom Raise Operation (Shock Reducing Operation)) 1. During boom lower operation or when stopping boom raise operation, returning oil from the boom raise spool in control valve is routed to port 1 (4). 2. As spool (1) blocks the oil passage between port 1 (4) and port A (2), returning oil cannot flow directly to port A (2). 3. Port 1 (4) is connected to the spring A (6) side in spool (1) through inner passage 1 (8) and to oil chamber (9) through inner passage 2 (5). 4. Pressure oil in oil chamber (9) flows from clearance C between spool (1) and housing (7) and pressure in oil chamber (9) decreases. Spool (1) is moved to the right by the pressure routed to the spring A (6) side. Therefore, clearance C between spool (1) and housing (7) is closed and pressure oil is blocked. 5. When clearance C is closed, pressure in oil chamber (9) increases and spool (1) is moved to the left. Then, clearance C is opened again and pressure oil flows to the port A (2) side. 6. As the operations in step 4 to step 5 are repeated and pressure oil is gradually returned to the port A (2) side, the control valve spool is returned slowly. 7. Consequently, the shockless valve reduces the shock during boom lower operation or when stopping boom raise operation.

TOJBQ40-EN-00(07/02/2020)

T3-6-7

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve 2

8 5 4

4 12-

Spool Port A

TOJBQ40-EN-00(07/02/2020)

34-

Spring B Port 1

56-

T3-6-8

Inner Passage 2 Spring A

TDC1-03-06-006-1 ja Inner Passage 1

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve 6

7 2

1 5

4 2

During Boom Lower Operation or When Stopping Boom Raise Operation (Shock Reducing Operation) TDC1-03-06-007-1 ja 123-

Spool Port A Spring B

456-

Port 1 Inner Passage 2 Spring A

789-

Housing Inner Passage 1 Oil Chamber

Operation of Flow Combiner Valve Control Spool ● The flow combiner valve control spool is shifted by travel (right) pilot pressure and supplies primary pilot pressure to the flow combiner valve in control valve. 1

Flow Combiner Valve Control Spool T178-03-06-014-1 ja

a- To Hydraulic Oil Tank b- Primary Pilot Pressure 1-

Spool

TOJBQ40-EN-00(07/02/2020)

c- To Flow Combiner Valve d- Travel (Right) Pilot Pressure 2-

Spring

T3-6-9

SECTION3 COMPONENT OPERATION Group6 Signal Control Valve Operation of Swing Parking Brake Release Spool ● The swing parking brake release spool is shifted by the boom, arm, bucket, swing, and auxiliary pilot pressure and supplies primary pilot pressure to the swing motor. 1

Swing Parking Brake Release Spool T178-03-06-014-2 ja

a- To Hydraulic Oil Tank b- Primary Pilot Pressure 1-

Spool

e- To Swing Motor f- Boom, Arm, Bucket, Swing, Auxiliary 2-

Spring

Operation of Arm Flow Rate Control Valve Control Spool ● The arm flow rate control valve control spool is shifted by arm roll-in pilot pressure (h) and supplies swing pilot pressure (b) to the arm 1 flow rate control valve (g) of the control valve. a

Arm Flow Rate Control Valve Control Spool T178-03-06-014-3 ja

a- To Hydraulic Oil Tank b- Primary Pilot Pressure 1-

Spool

TOJBQ40-EN-00(07/02/2020)

g- To Arm 1 Flow Rate Control Valve h- Arm Roll-In Pilot Pressure 2-

Spring

T3-6-10

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Outline of Pilot Shut-Off Solenoid Valve The pilot shut-off solenoid valve is a switch valve of the solenoid valve type. Spool (1) in the pilot shut-off solenoid valve is shifted by the pilot shut-off lever and turns ON/OFF pilot pressure oil to the pilot valve and signal control valve. Z

A3 Z T2

Z-Z

T1᳸T4

P A1᳸A3

1 TDC1-03-07-001-1 ja

P- Pressure Oil from Pilot Pump A1- Pilot Pressure to Travel Pilot Valve A2- Pilot Pressure to Boom, Bucket, Auxiliary Pilot Valve A3- Pilot Pressure to Arm, Swing Pilot Valve A4- Pilot Pressure to Signal Control Valve (Port PI) TOJBQ40-EN-00(07/02/2020)

T1- Returning Oil from Travel Pilot Valve T2- Returning Oil from Boom, Bucket, Auxiliary Pilot Valve T3- Returning Oil from Arm, Swing Pilot Valve T4- Returning Oil to Hydraulic Oil Tank

T3-7-1

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) 1-

Spool

Pilot Shut-Off Lever: LOCK Position 1. When the pilot shut-off lever is set to the LOCK position, the pilot shut-off relay is turned OFF, and the pilot shut-off solenoid valve is turned OFF. (Refer to SYSTEM/Electrical System.) 2. Pressure oil from the pilot pump is blocked by spool (1) in the pilot shut-off solenoid valve. 3. Each port in pilot valves (A1 to A3) is connected to the hydraulic oil tank. 4. Therefore, even if the control/travel control lever is operated, the pilot valve is not activated.

T1᳸T4

P A1᳸A4

Pilot Shut-Off Lever: LOCK Position TDEN-03-06-005-3 ja

T1- Returning Oil from Travel Pilot Valve T2- Returning Oil from Boom, Bucket, Auxiliary Pilot Valve T3- Returning Oil from Arm, Swing Pilot Valve T4- Returning Oil to Hydraulic Oil Tank

Spool

Pilot Shut-Off Lever: UNLOCK Position 1. When the pilot shut-off lever is set to the UNLOCK position, the pilot shut-off relay is turned ON, and the pilot shut-off solenoid valve is excited. (Refer to SYSTEM/Electrical System.) 2. Spool (1) in the pilot shut-off solenoid valve is pushed down, and pressure oil from the pilot pump flows to the pilot valve. 3. Consequently, when the control/travel control lever is operated, the pilot valve is activated.

TOJBQ40-EN-00(07/02/2020)

T3-7-2

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure)

T1᳸T4

P A1᳸A4

Pilot Shut-Off Lever: UNLOCK Position TDEN-03-06-007-2 ja

T1- Returning Oil from Travel Pilot Valve T2- Returning Oil from Boom, Bucket, Auxiliary Pilot Valve T3- Returning Oil from Arm, Swing Pilot Valve T4- Returning Oil to Hydraulic Oil Tank

Spool

Outline of Solenoid Valve The following solenoid valves are provided in this machine in order to control the functions. Solenoid Valve

Application

4-Spool Solenoid Valve Unit (Control Valve Side) The 4-spool solenoid valve unit (control valve side) is for valve control. 4-Spool Solenoid Valve Unit (Hydraulic Oil Tank The 4-spool solenoid valve unit (hydraulic oil tank side) is for valve con Side) trol.

Outline of 4-Spool Solenoid Valve Unit (Control Valve Side) The 4-spool solenoid valve unit on the control valve side controls the control valve according to the signal from MC (main controller). (Refer to SYSTEM/Control System.) The 4-spool solenoid valve unit on the control valve side consists of proportional solenoid valves (SC, SF, SI, and SG). ● 5-spool bypass shut-out control solenoid valve (SC): This valve controls the pump 2 bypass shut-out valve in the control valve. ● Boom mode selector control solenoid valve (SF): This valve controls the boom overload relief valve in the control valve (2-step relief on the boom rod side). ● Swing flow rate control solenoid valve (SI): This valve controls the swing flow rate control valve in the control valve. ● Arm 2 flow rate control solenoid valve (SG): This valve controls the arm 2 flow rate control valve in the control valve.

TOJBQ40-EN-00(07/02/2020)

T3-7-3

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) SC

TJAQ-05-04-010-1 ja

Outline of 4-Spool Solenoid Valve Unit (Hydraulic Oil Tank Side) The 4-spool solenoid valve unit on the hydraulic oil tank side controls the control valve and the valve in the travel motor according to the signal from MC (main controller). (Refer to SYSTEM/Control System.) The 4-spool solenoid valve unit on the hydraulic oil tank side consists of proportional solenoid valves (SC, SF, SI, and SG). ● Travel motor displacement angle control solenoid valve (SC): This valve controls the travel motor displacement angle control valve in the travel motor. ● Main relief valve control solenoid valve (SF): This valve controls the main relief valve in the control valve. ● Arm regenerative control solenoid valve (SI): This valve controls the arm regenerative cut valve in the control valve. ● 4-spool bypass shut-out control solenoid valve (SG): This valve controls the pump 1 bypass shut-out valve in the control valve. SC

TJAQ-05-04-010-1 ja

TOJBQ40-EN-00(07/02/2020)

T3-7-4

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Outline of Proportional Solenoid Valve The proportional solenoid valve is controlled by the electric current signal from MC (main controller) and outputs pressure in proportional to the electric current.

Operation of Proportional Solenoid Valve (When in Neutral) ● Spring (2) pushes spool (1) to the right and output port S is connected to tank port T. S

a TDAA-03-07-013-1 ja 1-

Spool

Spring

Solenoid

Operation of Proportional Solenoid Valve (When Excited) 1. Solenoid (3) pushes spool (1) to the left in proportion to the current value flowing to solenoid (3). 2. Pilot pressure oil from port P flows to output port S and pressure at output port S increases. 3. This pressure at output port S acts on stepped part (a) of spool (1). Spool (1) is pushed to the right due to difference in the pressure receiving area between stepped part (a). 4. When pressure at output port S increases and the force to push spool (1) to the right is balanced with the force to push spool (1) to the left due to solenoid (3), spool (1) is stopped moving and pressure at output port S stops increasing.

TOJBQ40-EN-00(07/02/2020)

T3-7-5

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) S

a TDAA-03-07-013-1 ja 1-

Spool

Spring

Solenoid

Outline of Radiator Fan Motor The radiator fan motor is operated by the pressure oil from the fan pump by the plunger motor to turn the fan for the radiator. The radiator fan motor consists of rotor (1), shaft (2), swash plate (3), shoe (4), retainer (5), and plunger (6). 1

3 TJAQ-03-07-006-1 ja

12-

Rotor Shaft

34-

Swash Plate Shoe

56-

Retainer Plunger

Outline of Radiator Fan Valve The radiator fan valve consists of relief valve (1) and fan reverse rotation control solenoid valve 1 (2). Relief valve (1) relieves the pressure oil from the fan pump when the pressure oil from the fan pump reaches the relief set pressure. When the circuit pressure decreases, the relief valve draws hydraulic oil from the hydraulic oil tank and prevents the occurrence of cavitation (make-up function). Fan reverse rotation control solenoid valve 1 (2) shifts reverse rotation spool (3) by the signal from MC (main controller).

TOJBQ40-EN-00(07/02/2020)

T3-7-6

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Reverse rotation spool (3) shifts the port of pressure oil flowing to the fan motor to operate the fan motor by forward or reverse rotation. (Refer to SYSTEM/Control System.) 2 M1

M2 M1

2 PP

T1 1 1

T1 TJAQ-03-07-007-1 ja

M1- Port M1 (To Fan Motor: Forward rotation, from Fan Mo T1- Port T1 (To Hydraulic Oil Tank) tor: Reverse rotation) M2- Port M2 (From Fan Motor: Forward rotation, to Fan Mo PP- Port PP (From Pilot Pump) tor: Reverse rotation) P1- Port P1 (From Fan Pump) 1-

Relief Valve

Fan Reverse Rotation Control Solenoid Valve 1

Reverse Rotation Spool

Relief Operation of Radiator Fan Valve 1. Pressure in port HP (fan pump) acts on pilot poppet (8) through orifice (1) of piston (10). 2. When pressure in port HP reaches the set pressure of spring B (6), pilot poppet (8) is opened. Pressure oil from passage A (5) flows along the outer circumference of sleeve (3) and flows to port T1 (hydraulic oil tank). 3. At this time, a differential pressure occurs between port HP and spring chamber (9) due to orifice (1). 4. When the force generated by this differential pressure reaches the set pressure of spring A (4), piston (10) and main poppet (2) are opened and pressure oil from port HP flows to port T1 to reduce the pressure from the fan pump. 5. When the fan circuit pressure decreases to the specified level, piston (10) and main poppet (2) are closed by the force of spring A (4).

TOJBQ40-EN-00(07/02/2020)

T3-7-7

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure)

4 9

T1 TJAQ-03-07-008-1 ja

HP- From Fan Pump 123-

Orifice Main Poppet Sleeve

T1- Port T1 (To Hydraulic Oil Tank) 456-

Spring A Passage A Spring B

8910-

Pilot Poppet Spring Chamber Piston

Make-Up Operation of Radiator Fan Valve 1. When the pressure in port HP (actuator circuit) decreases lower than the pressure in port T1 (hydraulic oil tank), sleeve (3) is moved to the right. 2. Hydraulic oil in port T1 flows to port HP and cavitation is prevented. 3. When the pressure in port HP increases to the specified pressure, sleeve (3) is closed by the force of spring C (7).

T1 TJAQ-03-07-009-1 ja

HP- Actuator Circuit TOJBQ40-EN-00(07/02/2020)

T1- Port T1 (To Hydraulic Oil Tank)

T3-7-8

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) 3-

Sleeve

Spring C

Outline of Oil Cooler Fan Motor The oil cooler fan motor is operated by the pressure oil from the fan pump by the plunger motor to turn the fan for the oil cooler. The oil cooler fan motor consists of rotor (1), shaft (2), swash plate (3), shoe (4), retainer (5), and plunger (6). 1

6 5

56-

Retainer Plunger

TJBQ-03-07-001-1 ja 12-

Rotor Shaft

34-

Swash Plate Shoe

Outline of Oil Cooler Fan Valve The oil cooler fan valve consists of fan reverse rotation control solenoid valve 2 (1), oil cooler fan control valve (2), fan speed control solenoid valve (3), and reverse rotation spool (4). Fan speed control solenoid valve (3) relieves the pressure oil from the fan pump by the signal from MC (main controller). Fan reverse rotation control solenoid valve 2 (1) controls the fan motor rotating direction (forward or reverse) by the signal from MC (main controller). Oil cooler fan valve (2) is shifted when fan speed control solenoid valve (3) is relieved and relieves the pressure oil from the fan pump. Pressure oil flowing to the fan motor is controlled to the optimum level as a result of fan speed control solenoid valve (3) and oil cooler fan valve (2) relieving the pressure oil from the fan pump. Reverse rotation spool (4) shifts the port of pressure oil flowing to the fan motor to operate the fan motor by forward or reverse rotation. (Refer to SYSTEM/Control System.)

TOJBQ40-EN-00(07/02/2020)

T3-7-9

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) T B A

1 3 2

T P

TJBQ-03-07-002-1 ja

A- Port A (To Fan Motor: Forward rotation, from Fan Motor: Re verse rotation) B- Port B (From Fan Motor: Forward rotation, to Fan Motor: Re verse rotation) P- Port P (From Fan Pump)

T- Port T (To Hydraulic Oil Tank)

Fan Speed Control Solenoid Valve

Fan Reverse Rotation Control Solenoid Valve 2

TOJBQ40-EN-00(07/02/2020)

Oil Cooler Fan Control Valve

T3-7-10

Dr- Port Dr (To Fan Motor)

Reverse Rotation Spool

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Outline of ON/OFF Solenoid Valve The ON/OFF solenoid valve is shifted by each control switch, and shifts pilot pressure.

Operation of ON/OFF Solenoid Valve (when in Neutral) Spool (1) is pushed to the right by spring (2). Output port S is connected to tank port T. 1

2 S

T TDAA-03-07-014-1 ja 1-

Spool

Spring

Solenoid

Operation of ON/OFF Solenoid Valve (When in Operation) As solenoid (3) is excited, spool (1) is pushed to the left. Pilot port P is connected to output port S and tank port T is blocked. 1

2 S

T TDAA-03-07-014-1 ja 1-

Spool

TOJBQ40-EN-00(07/02/2020)

Spring

T3-7-11

Solenoid

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Outline of Pilot Relief Valve Pilot relief valve (2) is built into pilot filter (3). Pilot relief valve (2) functions to regulate pilot pump pressure supplied to port P (1) to a constant pressure. 2 1

T178-03-07-001-1 ja 1-

Port P

TOJBQ40-EN-00(07/02/2020)

Pilot Relief Valve

T3-7-12

Pilot Filter

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Outline of Recirculation Valve Recirculation valve (1) is installed in fuel pre-filter (2). Recirculation valve (1) circulates a part of returning fuel which has been warmed in the engine without returning to the fuel tank when fuel temperature is low. Fuel temperature rises and clogging of the fuel filter is prevented. When fuel temperature rises beyond the specified value, it makes all fuel from the engine return to the fuel tank and keeps fuel appropriate temperature. A

A-A

A-A b

4 5

E TDC1-03-07-005-1 ja

a- From Engine b- To Fuel Tank c- To Fuel Pre-Filter 12-

Recirculation Valve Fuel Pre-Filter

D- When Fuel Temperature is Low E- When Fuel Temperature is High 34-

Spring Piston

56-

Spool Thermostat

Outline of Shockless Valve The shockless valve is provided in the boom lower circuit and functions when the boom lower control lever is returned suddenly.

TOJBQ40-EN-00(07/02/2020)

T3-7-13

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) Operation of Shockless Valve Operation 1. When the boom lower control lever is returned, returning oil from the spool (boom lower side) in the control valve acts on port A. 2. Pressure oil from port A flows through orifice (6) to chamber D (1). 3. Pressure oil in chamber D (1) flows to port B through passage (2) in spool (5) and housing (4), and pressure in chamber D (1) decreases. 4. As a pressure difference occurs between the front and rear of orifice (6), spool (5) is moved to the right by the pressure applied to the spring (3) side. Therefore, passage (2) in spool (5) and housing (4) is closed and pressure oil is limited. 5. When passage (2) is closed, the pressure difference at chamber D (1) is eliminated and spool (5) is returned to the left by the force of spring (3). Therefore, passage (2) is opened again and pressure oil flows to port B. 6. As the operations in step 3 to step 5 are repeated and pressure oil is gradually returned to the port B side, the control valve spool is returned slowly.

TOJBQ40-EN-00(07/02/2020)

T3-7-14

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) 6

5 A

B 3

D TJAQ-03-07-010-1 ja

A- Port A 12-

Chamber D Passage

B- Port B 34-

Spring Housing

56-

Spool Orifice

Outline of Accumulator (Pilot Circuit) The accumulator is provided in the pilot circuit and functions to absorb hydraulic pulsations and hold (for a short time) pilot pressure immediately after the engine is stopped. The accumulator mainly consists of body (5), holder (4), bladder (2) with nitrogen gas (N2) sealed inside, and poppet (1).

TOJBQ40-EN-00(07/02/2020)

T3-7-15

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) 1. Pressure oil from the pilot pump enters the accumulator through port A (a) and compresses bladder (2) until it balances with the pressure of nitrogen gas (b) in bladder (2). 2. When the supply of pressure oil in the circuit stops due to an operation such as stopping the engine, compressed bladder (2) expands and accumulated oil is supplied to pilot circuit (d) through port A (a). 6 1 5

b 4

c 3

a d T105-02-10-003-2 ja

a- Port A b- Nitrogen Gas (N2) 12-

Poppet Bladder

c- Pilot Pressure Oil d- To Pilot Circuit 34-

Oil Port Holder

56-

Body Gas Plug

Outline of Distribution Valve Distribution valve (13) is provided in the auto-lubrication circuit and functions to distribute grease from the grease pump to each lubrication place. Proximity switch (14) detects the amount of grease to distribute and outputs the signal to MC. (Refer to SYSTEM/Control System/Auto-Lubrication Control.) 13

TJAQ-03-07-016-1 ja 13-

Distribution Valve

14-

Proximity Switch

Operation of Distribution Valve 1. Grease from the grease pump acts on the right side of piston (15) A through passage G (G).

TOJBQ40-EN-00(07/02/2020)

T3-7-16

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) 2. Therefore, piston (15) A moves to the left. Grease on the left side of piston A flows to port 2 (2) through passage H (H) and piston (15) F. a 15 11

G TJAQ-03-07-017-1 ja

a- From Grease Pump H- Passage H 1234-

Port 1 Port 2 Port 3 Port 4

G- Passage G 5678-

Port 5 Port 6 Port 7 Port 8

9101112-

Port 9 Port 10 Port 11 Port 12

15-

Piston

3. When piston (15) A moves to the left, grease from the grease pump acts on the right side of piston (15) B through passage I (I). 4. Therefore, piston (15) B moves to the left. Grease on the left side of piston (15) B flows to port 11 (11) through passage J (J) and piston (15) A. a 15

TJAQ-03-07-018-1 ja

a- From Grease Pump I- Passage I 1234-

Port 1 Port 2 Port 3 Port 4

TOJBQ40-EN-00(07/02/2020)

J- Passage J 5678-

Port 5 Port 6 Port 7 Port 8

9101112-

T3-7-17

Port 9 Port 10 Port 11 Port 12

15-

Piston

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) 5. When piston (15) B moves to the left, grease from the grease pump acts on the right side of piston (15) C through passage K (K). 6. Therefore, piston (15) C moves to the left. Grease on the left side of piston (15) C flows to port 9 (9) through passage L (L) and piston (15) B. 7. The operations from step 3 to step 6 are repeated, and grease is discharged in sequence to port 11, port 9, port 7, port 5, and port 3. a 15

TJAQ-03-07-019-1 ja

a- From Grease Pump K- Passage K 1234-

Port 1 Port 2 Port 3 Port 4

L- Passage L 5678-

Port 5 Port 6 Port 7 Port 8

9101112-

Port 9 Port 10 Port 11 Port 12

15-

Piston

8. When piston (15) F moves to the left, grease from the grease pump acts on the left side of piston (15) A through passage H (H). 9. Therefore, piston (15) A moves to the right. Grease on the right side of piston (15) A flows to port 1 (1) through passage G (G) and piston (15) F. a 15 11

G TJAQ-03-07-020-1 ja

a- From Grease Pump

TOJBQ40-EN-00(07/02/2020)

H- Passage H

T3-7-18

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) G- Passage G 1234-

Port 1 Port 2 Port 3 Port 4

5678-

Port 5 Port 6 Port 7 Port 8

9101112-

Port 9 Port 10 Port 11 Port 12

15-

Piston

10. When piston (15) A moves to the right, grease from the grease pump acts on the left side of piston (15) B through passage J (J). 11. Therefore, piston (15) B moves to the right. Grease on the right side of piston (15) B flows to port 12 (12) through passage I (I) and piston (15) A. 12. The operations from step 10 to step 11 are repeated, and grease is discharged in sequence to port 12, port 10, port 8, port 6, and port 4. a 15

TJAQ-03-07-021-1 ja

a- From Grease Pump I- Passage I 1234-

Port 1 Port 2 Port 3 Port 4

TOJBQ40-EN-00(07/02/2020)

J- Passage J 5678-

Port 5 Port 6 Port 7 Port 8

9101112-

T3-7-19

Port 9 Port 10 Port 11 Port 12

15-

Piston

SECTION3 COMPONENT OPERATION Group7 Others (Upperstructure) MEMO

TOJBQ40-EN-00(07/02/2020)

T3-7-20

SECTION3 COMPONENT OPERATION Group8 Others (Undercarriage) Outline of Swing Bearing The swing bearing supports the upperstructure on the undercarriage and allows the upperstructure to swing smoothly. This bearing is a single row type ball bearing and consists of outer race (1), inner race (3), balls (6), supports (5), and seals (2, 4). Outer race (1) is bolted to the upperstructure. Inner race (3) is bolted to the undercarriage. The internal gear of inner race (3) meshes with the output shaft of the swing reduction gear.

1 2

5 3

6 T135-03-02-001-1 ja 12-

Outer Race Seal

34-

Inner Race Seal

56-

Support Ball

Outline of Center Joint The center joint is a joint which can turn freely. When the upperstructure swings, the center joint eliminates twisting of the hoses and allows pressure oil to flow the travel motors. Spindle (1) is secured to the upperstructure and cannot turn. Body (2) is secured to the swing center of the undercarriage. Pressure oil flows to the right and left travel motors through spindle (1) and each oil port of body (2). Seals (3) prevent oil leakages between spindle (1) and body (2).

TOJBQ40-EN-00(07/02/2020)

T3-8-1

SECTION3 COMPONENT OPERATION Group8 Others (Undercarriage) a

b c

d a

f c d b a

f :g :h :e TJAQ-03-08-001-1 ja

a- Travel (Left Reverse) b- Travel (Right Reverse) c- Travel (Right Forward) d- Travel (Left Forward) 1-

Spindle

e- Pilot Port for Travel Mode Control f- Drain g- Forward h- Reverse 2-

Body

Seal

Outline of Track Adjuster The track adjuster consists of spring (3), adjuster cylinder (1), etc., and is held by the side frame. The track adjuster absorbs the load applied to the front idler (4) part at spring (3). Track sag is adjusted by adjuster cylinder (1). •

When grease is supplied through grease fitting (5), grease fills chamber (a) in adjuster cylinder (1), pushes piston rod (2), and reduces track sag.

TOJBQ40-EN-00(07/02/2020)

T3-8-2

SECTION3 COMPONENT OPERATION Group8 Others (Undercarriage) 5

TJAQ-03-08-002-1 ja 12-

Adjuster Cylinder Piston Rod

TOJBQ40-EN-00(07/02/2020)

34-

Spring Front Idler

T3-8-3

Grease Fitting

SECTION3 COMPONENT OPERATION Group8 Others (Undercarriage) MEMO

TOJBQ40-EN-00(07/02/2020)

T3-8-4

Hitachi Construction Machinery Co., Ltd. Attn: Service Material Development Tel: 029-832-9673 Fax: 029-831-1162 E-mail: HCM-TIC-GES@hitachi-kenki.com

Hitachi ref. No.

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