Hitachi EX1200-7 Hydraulic Excavator Operational Technical Manual TOKAA90-EN-00 (1) by www.heydownloads.com

PART NO.

TOKAA90-EN-00

EX1200-7 HYDRAULIC EXCAVATOR

Operational Principle

TECHNICAL MANUAL OPERATIONAL PRINCIPLE

EX1200-7

Hydraulic Excavator

BACKHOE FRONT SPECIFICATIONS

URL:http://www.hitachi-c-m.com

TOKAA90-EN-00

PRINTED IN JAPAN (K) 2018, 05

Technical Manual

Service Manual consists of the following separate Part No. Technical Manual (Operational Principle) : Vol. No.TOKAA90-EN Technical Manual (Troubleshooting) : Vol. No.TTKAA90-EN Workshop Manual : Vol. No.WKAA90-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.

 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 it for usage.):  PS Information Center Hitachi Construction Machinery Co., Ltd.  TEL: 81-29-832-7084  FAX: 81-29-831-1162  E-mail: HCM-TIC-GES@hitachi-kenki.com

 Be sure to thoroughly read this manual for correct product information and service procedures.

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  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.

This manual consists the Technical Manual and the Workshop 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.

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

 Workshop Manual: W 1-3-2-5 W 1 3 2 5

Technical Manual Section Number Group Number Consecutive Page Number for Each Group

TOKAA90-EN-00

IN-1

Workshop Manual Section Number Group Number Sub Group Number Consecutive Page Number for Each Group

INTRODUCTION 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.

CAUTION: Indicates potentially hazardous situation which could, if not avoided, result in personal injury or death.

d This is the safety alert symbol. When you see this

IMPORTANT: Indicates a situation which, if not conformed to the instructions, could result in damage to the machine.

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.

fNOTE: Indicates supplementary technical information or knowhow.

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

To Convert From

Into

Multiply By

Length

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

Pressure

MPa

kgf/cm

MPa

psi

145.0

Power

1.360

1.341

Temperature

°C

°F

°C×1.8+32

Velocity

km/h

mph

0.6214

min

rpm

1.0

L/min

US gpm

0.2642

mL/rev

cc/rev

1.0

Volume

Flow rate

TOKAA90-EN-00

-1

IN-2

0.10197 2

10.197

SYMBOL AND ABBREVIATION Symbol / Abbreviation TO TT T/M W, W/M MC1 MC2 ECM DLU GSM

BPU CSU

FMU ODR RPU

WIU GPS CAN

Name

Explanation

Technical manual (Operational principle) Technical manual (Troubleshooting) Technical manual Workshop manual

Technical manual (Operational Principle). Technical manual (Troubleshooting). Technical manual. Workshop manual (Removal and Installation, Disassembly and Assembly). Main Controller 1 Main controller 1. MC1 controls the engine, pump, and valve according to the machine operating condition. Main Controller 2 Main controller 2. MC2 controls the lights, wiper, washer, and sliding fold-in ladder alarm. Engine Control Module Engine controller. ECM controls fuel injection amount according to the machine operating condition. Data Logging Unit Data logging unit. DLU records the information from each controller. Global System for Mobile communications Communication controller. GSM is a type of wireless controller communication system, is used in more than on 100 countries around Europe and Asia, and becomes the factual global standards of the mobile telephone. Basic Performance Monitoring Unit Basic performance monitoring unit. BPU semiautomatically measures the basic performance. Contamination Sensing Unit Contamination sensing unit. CSU senses contaminants in the drain circuits of the main pump, swing motor, and travel motor. Fatigue Monitoring Unit Mechanical fatigue monitoring unit. FMU monitors mechanical fatigue of the structures. Operation Data Recorder Operation data recorder. ODR automatically records the data related to the detected information which has been set. Radiation Performance monitoring Unit RPU monitors the oil cooler state and the engine cooling system including the radiator by using each temperature sensor. Wireless Interface Unit WIU outputs the machine operation data to PC via wireless LAN. Global Positioning System Global positioning system. Controller Area Network CAN communication. CAN is a serial communications protocol internationally-standardized by ISO (International Organization for Standardization).

TOKAA90-EN-00

SY-1

SYMBOL AND ABBREVIATION Symbol / Name Abbreviation OP, OPT Option MPDr. Maintenance Pro Dr. A/I WU Li ATT

Auto-Idle Warming-Up Low (Slow) Idle Attachment

HI, Hi LO, Lo

High Low

TOKAA90-EN-00

Explanation Optional component. MPDr. is software that troubleshooting, monitoring, and adjustment. Auto-idle. Warming-up. Slow idle engine speed. Attachment. Attachment is optional parts such as breaker, crusher, and pulverizer in this manual. Travel fast position. Travel slow position.

SY-2

SECTION AND GROUP SECTION 1 GENERAL Group 1 Specifications CONTENTS

Group 2 Component Layout Group 3 Component Specifications

SECTION 2 SYSTEM TECHNICAL MANUAL (Operational Principle)

Group 1 Controller Group 2 Control System Group 3 Engine System Group 4 Hydraulic System Group 5 Electrical System Group 6 Air Conditioning System

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Group 2 Swing Device Group 3 Control Valve Group 4 Control Equipment Group 5 Travel Device Group 6 Signal Control Valve Group 7 Others (Upperstructure) Group 8 Others (Undercarriage)

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.

TOKAA90-EN-00

TECHNICAL MANUAL (Troubleshooting) SECTION 4 OPERATIONAL PERFORMANCE TEST Group 1 Introduction Group 2 Standard Group 3 Engine Test Group 4 Machine Performance Test Group 5 Component Test

SECTION 5 TROUBLESHOOTING Group 1 Diagnosing Procedure Group 2 Monitor Group 3 Cross Reference Table Group 4 Component Layout Group 5 Troubleshooting A Group 6 Troubleshooting B Group 7 Troubleshooting C Group 8 Air Conditioner Group 9 e-Service

WORKSHOP MANUAL SECTION 1 GENERAL INFORMATION Group 1 Precautions for Disassembling and Assembling Group 2 Tightening Group 3 Painting Group 4 Bleeding Air Group 5 Releasing Pressure Group 6 Preparation SECTION 2 MAINTENANCE STANDARD Group 1 Upperstructure Group 2 Undercarriage Group 3 Front Attachment SECTION 3 UPPERSTRUCTURE Group 1 Cab Group 2 Counterweight Group 3 Main Frame Group 4 Engine Group 5 Radiator Assembly Group 6 Oil Cooler Assembly Group 7 Hydraulic Oil Tank Group 8 Fuel Tank Group 9 Pump Device Group 10 Control Valve Group 11 Swing Device Group 12 Pilot Valve Group 13 Solenoid Valve Group 14 Signal Control Valve Group 15 Muffer Group 16 Fan Valve Group 17 Fan Motor

TOKAA90-EN-00

SECTION 4 UNDERCARRIAGE Group 1 Swing Bearing Group 2 Travel Device Group 3 Center Joint Group 4 Track Adjuster Group 5 Front Idler Group 6 Upper and Lower Roller Group 7 Track SECTION 5 FRONT ATTACHMENT Group 1 Front Attachment Group 2 Cylinder Group 3 Bushing and Point

SECTION 1

GENERAL CONTENTS Group 1 Specifications

Specifications........................................................................ T1-1-1 Working Range..................................................................... T1-1-2

Group 2 Component Layout

Main Component................................................................. T1-2-1 Front Attachment ............................................................... T1-2-2 Electrical System (Overview)........................................... T1-2-3 Electrical System (In Cab).................................................. T1-2-4 Electrical System (Switch Panel)..................................... T1-2-5 Electrical System (Electrical Equipment Box)............. T1-2-6 Electrical System (Rear Tray) ........................................... T1-2-7 Electrical System (Battery Box)........................................ T1-2-8 Around Air Cleaner.............................................................. T1-2-9 Around Engine Compartment ....................................... T1-2-9 Pressure Sensor (4-Spool Side)/ Pressure Sensor (5-Spool Side)................................T1-2-10 Around Pump Device ......................................................T1-2-11 Pump Device.......................................................................T1-2-12 Control Valve ......................................................................T1-2-13 Signal Control Valve..........................................................T1-2-14 Solenoid Valve.....................................................................T1-2-15 Fan Valve (Oil Cooler, Radiator).....................................T1-2-15 Engine....................................................................................T1-2-16 Around Oil Cooler..............................................................T1-2-17 Around Radiator.................................................................T1-2-17 Auto-Lubrication Device.................................................T1-2-18 Swing Device and Pressure Sensors for Front Attachment.........................................................T1-2-19 Hydraulic Oil Tank..............................................................T1-2-20 Fuel Tank...............................................................................T1-2-20 Sliding Fold-In Ladder......................................................T1-2-21

Group 3 Component Specifications

Engine...................................................................................... T1-3-1 Engine Accessories.............................................................. T1-3-5 Hydraulic Component........................................................ T1-3-6 Electrical Component.......................................................T1-3-10

TOKAA90-EN-00

KAA90T-1-1

(Blank)

TOKAA90-EN-00

KAA90T-1-2

SECTION 1 GENERAL Group 1 Specifications Specifications

E D I

H F

Model Type of Front-End Attachment

Bucket Capacity (Heaped) Operating Weight Engine A: Overall Width B: Cab Height C: Rear End Swing Radius D: Minimum Ground Clearance E: Counterweight Clearance F: Undercarriage Length G: Undercarriage Width H: Sprocket Center to Idle Center I: Track Shoe Width Ground Pressure Swing Speed Travel Speed (fast/slow) Gradeability

m3 kg (lb) mm (ft·in) mm (ft·in) mm (ft·in) mm (ft·in) mm (ft·in) mm (ft·in) mm (ft·in) mm (ft·in) mm (ft·in) kPa (kgf/cm2) (psi) min-1 (rpm) km/h % (Degree)

fNOTE: *The dimensions do not include the height of the shoe lug.

TOKAA90-EN-00

T1-1-1

MKAA-12-001

EX1200-7 Hydraulic Excavator Backhoe BE Backhoe [9.0 m (29’ 6”) boom, [7.55 m (24’ 9”) BE-boom, 3.6 m (11’ 10”) arm] 3.4 m (11’ 2”) BE-arm] 5.2 7.0 111500 (253600) 117000 (258000) Cummins QSK23 567 kW/1800 min ¹ (770 PS/1800 rpm) 5470 (17’ 9”) 4350 (14’ 3”) 4900 (16’ 1”) *1020 (3’ 4”) 1820 (6’ 0”) 6500 (21’ 4”) 4600 (15’ 1”) 5090 (16’ 8”) 700 (28”) (Grouser shoe) 145 (1.48) (21.1) 148 (1.51) (21.5) 5.2 3.5/2.4 70 (35)

SECTION 1 GENERAL Group 1 Specifications Working Range (Backhoe)

E B

A' A

Boom Length Arm Length A : Maximum Digging Reach A’ : Maximum Digging Reach (on ground) B : Maximum Digging Depth C : Maximum Cutting Height D : Maximum Dumping Height E : Maximum Vertical Wall

TOKAA90-EN-00

MKAA-12-002

9.00 m (29’ 6”) 3.60 m (11’ 10”) 15350 mm (50’ 4”) 15010 mm (49’ 3”) 9380 mm (30’ 9”) 13460 mm (44’ 2”) 9080 mm (29’ 10”) 6450 mm (21’ 2”)

T1-1-2

SECTION 1 GENERAL Group 1 Specifications Working Range (Be Backhoe)

A' A

Boom Length Arm Length A : Maximum Digging Reach A’ : Maximum Digging Reach (on ground) B : Maximum Digging Depth C : Maximum Cutting Height D : Maximum Dumping Height E : Maximum Vertical Wall

TOKAA90-EN-00

MKAA-12-003

7.55 m (24’ 9”) BE-boom 3.40 m (11’ 2”) BE-arm 13790 mm (45’ 2”) 13410 mm (44’ 0”) 8100 mm (26’ 6”) 12340 mm (40’ 5”) 8010 mm (26’ 3”) 4440 mm (14’ 6”)

T1-1-3

SECTION 1 GENERAL Group 1 Specifications (Blank)

TOKAA90-EN-00

T1-1-4

SECTION 1 GENERAL Group 2 Component Layout Main Component 34 30

9 33

3 2

14 15 16 17

19 20 21 28 27

TKAA90-01-02-001

26 234567891011-

Auto-Lubrication Device Tool Box Fuel Tank (Refer to T1-2-22.) Swing Device Signal Control Valve Main Control Valve 2-Spool Solenoid Valve Unit Radiator 4-Spool Solenoid Valve Unit Muffer

TOKAA90-EN-00

12- Engine 13- Air Cleaner 14- Around Pump Device (Refer to T1-2-11.) 15- Pump Transmission 16- Hydraulic Oil Tank (Refer to T1-2-22.) 17- Swing Control Valve 18- Travel Device 19- Sliding Fold-In Ladder

202122232425-

Lower Roller Battery Upper Roller Accumulator Track Adjuster Front Attachment/Swing Pilot Valve 26- Front Idler 27- Travel Pilot Valve 28- Swing Bearing

T1-2-1

2930313233-

Center Joint Oil Cooler Fuel Cooler Air Conditioner Condenser Pump Transmission Oil Cooler 34- Intercooler

SECTION 1 GENERAL Group 2 Component Layout Front Attachment 4 3

2 1

5 6

TKAB-01-02-002

12-

Bucket Bucket Cylinder

TOKAA90-EN-00

34-

Arm Cylinder Boom

56-

T1-2-2

Boom Cylinder Arm

SECTION 1 GENERAL Group 2 Component Layout Electrical System (Overview) 11

10 13

14 6 5 3

15 17

32 19 21 20 22 23 24

31 26 25 30

27 28 29

13-

5678-

Work Light (Right) Components Related with Auto-Lubrication Device (Refer to T1-2-18.) Swing Device and Pressure Sensors for Front Attachment (Refer to T1-2-19.) Satellite Communication Antenna WIU Antenna Around Oil Cooler (Refer to T1-2-17.) Components Related with Signal Control Valve (Refer to T1-2-14.)

TOKAA90-EN-00

101113141516-

17-

Components Related with Main Control Valve (Refer to T1-2-13.) Around Radiator (Refer to T12-17.) Components Related with Engine (Refer to T1-2-17.) Rear View Camera Rear Light Engine Stop Switch 2 Components Related with Pump Device (Refer to T1-212.) Around Air Cleaner (Refer to T1-2-9.)

18- Around Engine Compartment (Refer to T1-2-9.) 19- Components Related with Swing Control Valve (Refer to T1-2-13.) 20- Pressure Sensor (4-Spool Side)/Pressure Sensor (5-Spool Side) (Refer to T1-2-10.) 21- 4-Spool Solenoid Valve Unit 22- 2-Spool Solenoid Valve Unit 23- Hydraulic Oil Level Check Switch 24- Cab Rear Light (Option) 25- Electrical System (Battery Box) (Refer to T1-2-8.)

T1-2-3

TKAA90-01-02-002 26- Step Light 27- Electrical System (Electrical Equipment Box) (Refer to T12-6.) 28- Electrical System (In Cab) (Refer to T1-2-4.) 29- Work Light (Left) 30- Monitor 31- Work Light (Cab Upper) 32- Horn

SECTION 1 GENERAL Group 2 Component Layout Electrical System (In Cab)

View A (Illustration viewed in the cab toward the cab door )

TKAB-01-02-051

5 6 TKAB-01-02-004

123-

Aerial Angle Monitor (Option) Monitor Electrical System (Switch Panel) (Refer to T1-2-5.)

TOKAA90-EN-00

Electrical System (Electrical Equipment Box) (Refer to T1-2-6.)

56-

T1-2-4

Electrical System (Rear Tray) (Refer to T1-2-7.) Electrical System (Switch Panel) (Refer to T1-2-5.)

78910-

Step Light Switch Engine Stop Indicator Engine Stop Switch 1 Cab Door

SECTION 1 GENERAL Group 2 Component Layout Electrical System (Switch Panel) Switch Panel (Left)

Switch Panel (Right) 8

11 12

13 14 15 24 23

2 3 4

16 17 18 19

5 22 6

TKAB-01-02-005

123456-

Horn Switch Travel Alarm Deactivation Switch (Option) Seat Heater Switch (Option)/ Cab Rear Light Switch (Option) Boom Mode Switch Fan Reverse Rotation Switch Lubrication Mode Selection Switch

TOKAA90-EN-00

789-

Buzzer Deactivation Switch Power Digging Switch AUTO/OFF Switch/Fan Switch (Air Conditioner) 10- Temperature Control Switch/ MODE Switch (Air Conditioner) 11- Return to Previous Screen Switch (Monitor)

TKAB-01-02-006

12- Return to Basic Screen Switch (Monitor) 13- Selector/Set Switch (Monitor) 14- AM/FM Selector/Tuning Switch (Radio) 15- Power Switch/Volume Control Switch (Radio) 16- Engine Control Dial 17- Auto-Idle Switch

T1-2-5

18- Travel Mode Switch 19- Work Light Switch 20- Screen Changeover Switch (for Aerial Angle) (Option) 21- Power Mode Switch 22- Numeric Keypad 23- Wiper/Washer Switch 24- Key Switch

SECTION 1 GENERAL Group 2 Component Layout Electrical System (Electrical Equipment Box)

1 2 3 4 5 11

10 9

8 7

Detail A

TKAB-01-02-007

17 18

25 24

123456-

Fault Code Selection Switch Engine Troubleshooting Switch Engine Stop Indicator Lamp Engine Warning Indicator Lamp Engine Maintenance Indicator Lamp Connector for DLU

TOKAA90-EN-00

7891011121314-

Connector for PC (Cummins) CSU (Option) MC1 DLU MC2 Unused (R6) Wiper Relay Low (R7) Work Light Relay 2 (Boom Light) (R12)

15- Wiper Relay High 2 (R8) 16- Work Light Relay 1 (Work Light) (R11) 17- Wiper Relay High 1 (R9) 18- Washer Relay (R10) 19- Unused (R5) 20- Unused (R4) 21- Auto-Lubrication Relay 1 (R13) 22- Unused (R3)

T1-2-6

TKAB-01-02-008 23- Sliding Fold-In Ladder Relay (R14) 24- Pump Transmission Oil Level Switch Relay (R2) 25- Step Light Relay (R1) 26- Auto-Lubrication Relay 2 (R31)

SECTION 1 GENERAL Group 2 Component Layout Electrical System (Rear Tray)

1 2 3

View A

Detail B

13 14 15 16

TKAB-01-02-009

6 5

29 28

27 17 1234567-

WIU (Option) Cigar Lighter 12V Socket Pump Regulator Pressure Learning Switch Fuse Box 3 (Option) Fuse Box 2 Fuse Box 1

TOKAA90-EN-00

891011121314-

12 V Power Unit Aerial Angle Controller (Option) Air Conditioner Controller GSM Monitor Controller Alternator Signal Relay (R33) Alternator Relay (R32)

23 TKAB-01-02-011

TKAB-01-02-010 1516171819202122-

T1-2-7

Pilot Shut-Off Relay (R26) Seat Heater Relay (Option) Radio Controller Security Horn Relay (R20) Horn Relay (R21) Load Dump Relay (R22) Starter Cut Relay (R23) Security Relay (R24)

23- ACC ON Relay 1 (R19) 24- ACC ON Relay 2 (R18) 25- Work Light Relay 3 (Work Light (Cab Upper)) (R28) 26- Auto Shut-Down Relay (R17) 27- Back Light Relay (R27) 28- ACC Cut Relay (R16) 29- Key Switch ON Cut Relay (R15)

SECTION 1 GENERAL Group 2 Component Layout Electrical System (Battery Box) Detail A

1 4

20 19 18 17

12-

Isolation Switch (Battery Circuit) Isolation Switch (Starter Circuit)

TOKAA90-EN-00

TKAB-01-02-012

3 3467-

Battery Washer Tank Battery Relay 1 Diode 1

8161718-

T1-2-8

Battery Relay 2 Slow Blow Fuse 4 (200 A) Slow Blow Fuse 1 (45 A) Slow Blow Fuse 3 (75 A)

TKAA90-01-02-007

19- Slow Blow Fuse 2 (75 A) 20- Fuse 3 (20 A)

SECTION 1 GENERAL Group 2 Component Layout Around Air Cleaner 1

4 1-

Air Cleaner

Drain Filter

2 3-

Pump Transmission Oil Filter

TKAB-01-02-016 4-

Pilot Filter

Around Engine Compartment 6

TKAB-01-02-053 TKAA90-01-02-003

Engine Oil Filter

TOKAA90-EN-00

Fuel Filter (Stage 1)

T1-2-9

SECTION 1 GENERAL Group 2 Component Layout Pressure Sensor (Main Control Valve 4-Spool Side)/Pressure Sensor (Main Control Valve 5-Spool Side) View A

2 TKAB-01-02-014

Pressure Sensor (4-Spool Side)

TOKAA90-EN-00

Pressure Sensor (5-Spool Side)

T1-2-10

1 TKAB-01-02-015

SECTION 1 GENERAL Group 2 Component Layout Around Pump Device

12-

Pump 3 Pump 2

TOKAA90-EN-00

34-

Engine Stop Switch 2 3-Unit Pump

56-

T1-2-11

TKAB-01-02-018

Pump 1 Fan Pump

SECTION 1 GENERAL Group 2 Component Layout Pump Device 1

6 12-

Pump 3 Regulator Pressure Sensor Pump Transmission Oil Level Switch

34-

Pump 2 Regulator Pressure Sensor Pump 2 Delivery Pressure Sensor

Views A, B, C

TKAB-01-02-019 5-

Pump 1 Delivery Pressure Sensor Pump 3 Delivery Pressure Sensor

Pump 1 Regulator Pressure Sensor

View D (3-Unit Pump)

9 10

TKAB-01-02-020

89-

Pump Regulator (Pumps 1, 2, 3) Pump Control Solenoid Valve (Pumps 1, 2, 3)

TOKAA90-EN-00

10- Transmission Lubrication Pump 11- Pilot Pump 12- Fan Pump

13- Fan Pump Regulator 14- Fan Pump Control Solenoid Valve

T1-2-12

TKAB-01-02-052

SECTION 1 GENERAL Group 2 Component Layout Control Valve Main Control Valve View A

2 3

TKAB-01-02-021

TKAB-01-02-022 12-

Press Sensor (Arm Roll-Out) Pressure Sensor (Boom Raise)

34-

Pressure Sensor (Bucket RollOut) Main Relief Valve

56-

Pressure Sensor (Bucket Roll-In) Pressure Sensor (Boom Lower)

789-

Press Sensor (Arm Roll-In) High-Pressure Filter High-Pressure Filter

Swing Control Valve 10

TKAB-01-02-023 10- High-Pressure Filter

TOKAA90-EN-00

11- Main Relief Valve

T1-2-13

SECTION 1 GENERAL Group 2 Component Layout Signal Control Valve Detail A B

2 3 TKAB-01-02-059

TKAB-01-02-025

View B Section C-C

8 14

T178-03-06-002

1234-

Signal Control Valve Pressure Sensor (SA) Pressure Sensor (SB) Pressure Sensor (SA) Mounting Part

TOKAA90-EN-00

5678-

TKAB-01-02-057

Pressure Sensor (SB) Mounting Part Pressure Sensor (Travel) Pressure Sensor (Swing) Boom Raise Shockless Valve

9- Auxiliary 10- Auxiliary 11- Flow Combiner Valve Control Spool

T1-2-14

12- Swing Parking Brake Release Spool 13- Auxiliary 14- Auxiliary

SECTION 1 GENERAL Group 2 Component Layout Solenoid Valve 2-Spool Solenoid Valve Unit

4-Spool Solenoid Valve Unit

5 1

TKAB-01-02-027

TKAB-01-02-058 12-

4-Spool Solenoid Valve Unit (SC) 4-Spool Solenoid Valve Unit (SF)

34-

4-Spool Solenoid Valve Unit (SI) 4-Spool Solenoid Valve Unit (SG)

56-

Fan Valve (Oil Cooler, Radiator)

9 TKAB-01-02-055 7-

Fan Reverse Rotation Control Solenoid Valve

TOKAA90-EN-00

89-

Fan Valve Relief Valve

T1-2-15

2-Spool Solenoid Valve Unit (SC) 2-Spool Solenoid Valve Unit (SI)

SECTION 1 GENERAL Group 2 Component Layout Engine 2

TKAA90-01-02-005

TKAA90-01-02-004

TKAA90-01-02-006 123-

Air Conditioner Compressor Boost Pressure Sensor ECM

TOKAA90-EN-00

457-

Coolant Filter Alternator Coolant Temperature Sensor

8- Starter 1 9- Starter 2 10- Engine Speed Sensor

T1-2-16

SECTION 1 GENERAL Group 2 Component Layout Around Oil Cooler 1

3 12-

View A

Fuel Filter (Stage 1) Oil Cooler Fan Valve

34-

Oil Cooler Fan Motor Oil Cooler

TKAB-01-02-035 5-

TKAB-01-02-036

Fuel Cooler

Around Radiator View B

78-

Coolant Level Sensor Radiator Fan Motor

TOKAA90-EN-00

TKAB-01-02-037

9- Radiator Fan Valve 10- Radiator

11- Intercooler 12- Air Conditioner Condenser

T1-2-17

TKAB-01-02-038

13- Receiver Tank 14- Pump Transmission Oil Cooler

SECTION 1 GENERAL Group 2 Component Layout Auto-Lubrication Device Quicklub Lubrication System (Standard) 1

5 6

TKAB-01-02-056 1-

Auto/Manual Selector Valve Lever Proximity Switch

345-

Distribution Valve Grease Pump Diode 23

Pail

Centro Matic Lubrication System (Option) 7

View A

10 A

11 13 12

TKAB-01-02-039

78-

Grease Pump Air Breather

TOKAA90-EN-00

Auto-Lubrication Solenoid Valve 10- Diode 22

15 11- Diode 3 12- Grease Tank 13- Grease Pressure Gauge

T1-2-18

TKAB-01-02-040

14- Auto/Manual Selector Valve Lever 15- Pressure Switch

SECTION 1 GENERAL Group 2 Component Layout Swing Device and Pressure Sensors for Front Attachment 1 B C

1 2 A

TKAB-01-02-041

2 View B

View A

1234-

Swing Motor Relief Valve Arm Bottom Pressure Sensor Boom Bottom Pressure Sensor

567-

Bucket Bottom Pressure Sensor Arm Rod Pressure Sensor Bucket Rod Pressure Sensor

TKAB-01-02-043

TKAB-01-02-042

View C

TOKAA90-EN-00

T1-2-19

TKAB-01-02-044

SECTION 1 GENERAL Group 2 Component Layout Hydraulic Oil Tank View A

1 1-

Hydraulic Oil Level Check Switch

TKAB-01-02-046

TKAB-01-02-045

Hydraulic Oil Level Gauge

Hydraulic Oil Temperature Sensor

Valve Limit Switch

Fuel Tank

TKAB-01-02-048

TKAB-01-02-047 5-

Fuel Level Gauge

TOKAA90-EN-00

Fuel Level Switch

T1-2-20

Fuel Level Sensor

SECTION 1 GENERAL Group 2 Component Layout Sliding Fold-In Ladder View A

TKAB-01-02-050 TKAB-01-02-049

A 1-

Sliding Fold-In Ladder

TOKAA90-EN-00

Sliding Fold-In Ladder Limit Switch

T1-2-21

SECTION 1 GENERAL Group 2 Component Layout (Blank)

TOKAA90-EN-00

T1-2-22

SECTION 1 GENERAL Group 3 Component Specifications Engine Manufacturer

Cummins Inc.

Model

QSK23-C

Type

Diesel, 4-Cycle, Water-cooled, Direct Injection Type, Exhaust Turbo Charged Type

Cyl. No.- Bore × Stroke

6-170 mm×170 mm (6-6.7×6.7 in)

Piston Displacement

23.15 L (6 US gal)

Rated Output

567 kW/1800 min-1 (771 PS/1800 rpm)

Compression Ratio

16:1

Dry Weight

2600 kg (5740 lb)

Firing Order

1-5-3-6-2-4

Rotation Direction Dimension Overall length × width × height

Counter clockwise (Viewed from flywheel side) 1859×940×1656 mm (6 ft×3 ft×5 ft 5 in)

TOKAA90-EN-00

T1-3-1

SECTION 1 GENERAL Group 3 Component Specifications COOLING SYSTEM

Thermostat

Cracking Temperature at Atmospheric Pressure: 77 °C Full Open: 90 °C

LUBRICATION SYSTEM

Water Pump

Centrifugal Type

Lubrication Pump Type

Gear Pump

Oil Filter

Full-Flow Paper Element Type with Bypass

STARTING SYSTEM Voltage/Output STARTING ASSIST SYSTEM Type ENGINE STOP SYSTEM Stop Method

24 V/7.5 kW×2 (24 V/10 PS×2) Ether Injection Type Electronic Control

ALTERNATOR

Type

Regulator Integrated AC Type

Voltage/Output

24 V/140 A

SUPERCHARGING SYSTEM

Type

Exhaust-Turbocharger Type with Lubrication, Water-Cooled Type

FUEL SYSTEM

Type

Cummins HPI

Governor

Electronic All Speed Control

TOKAA90-EN-00

T1-3-2

SECTION 1 GENERAL Group 3 Component Specifications IMPORTANT: This list shows design specifications, which are not servicing standards. Performance Fuel Consumption (When rated, Gross) Maximum Output Torque (Gross) No Load Speed Fast: Slow:

TOKAA90-EN-00

SAEJ1995 206 g/kW·h (151 g/PS·h) 3468 N·m at 1350 min-1 (2560 lbf·ft at 1350 rpm) 1950 ± 30 min-1 (rpm) 850 ± 30 min-1 (rpm)

T1-3-3

SECTION 1 GENERAL Group 3 Component Specifications Engine Performance Curve (QSK23-C) Test Condition: The engine operating with fuel system, not included are alternator and fan. Curves shown above represent gross engine performance capabilities obtained and corrected in accordance with SAE J1995 conditions of 100 kPa (14.5 psi) barometric pressure [91 m (300 ft) altitude] 25 °C (77 °F) inlet air temperature, and 1 kPa (0.1 psi) water vapor pressure with SAE No.2 diesel fuel.

N·m

min-1

TKAB-01-03-001

Output

TOKAA90-EN-00

Torque

T1-3-4

Engine Speed

SECTION 1 GENERAL Group 3 Component Specifications Engine Accessories Core Dimension (height × width × depth) Core Rows Fin Pitch Fin Type Radiation Area

Core Dimension (height × width × depth) Core Rows Fin Pitch Fin Type Radiation Area BATTERY

TOKAA90-EN-00

Radiator 1300×1285×100 mm (4 ft 3 in×4 ft 3 in×4 in) 1 row (3 used) 3.5/2 mm (0.1/2 in) ALW-4 202.65 m2 (242.4 yd2)

Oil Cooler 1190×1540.6×93 mm (3 ft 11 in×5 ft×4 in) 3 rows (6 used) 3.5/2 mm (0.1/2 in) CF40-1 167.15 m2 (200 yd2)

Intercooler 980×904×65 mm (3 ft 3 in×2 ft 12 in×3 in) 1 row (1 used) 4.0/2 mm (0.2/2 in) CFT 10-Hole Pipe 43.46 m2 (52 yd2)

Fuel Cooler 419.4×765×31 mm (1 ft 5 in×2 ft 6 in×1 in)

Pump Transmission Oil Cooler 284.4×312×40 mm (11 in×1 ft×2 in)

1 row (1 used) 3.5/2 mm (0.1/2 in) CF40-1 9.62 m2 (11.5 yd2)

1 row (1 used) 3.5 mm (0.1 in) Corrugated 3.34 m2 (4 yd2)

Type Nominal Voltage Capacity CCA Discharge Characteristics (-15 °C/500 A)

245H52 12 V 176 Ah (5-Hour Rate), 185 Ah (20-Hour Rate) 1170 A Duration 7.8 min 30-Second Voltage at Discharge 9.9 V Dimension (height × width 266×518×276 mm (11 in×1 ft 8 in×11 in) × length)

T1-3-5

SECTION 1 GENERAL Group 3 Component Specifications Hydraulic Component PUMP DEVICE

Drive Gear Ratio

Main Pump: 1.041 3-Unit Pump: 1.063

MAIN PUMP

Type

Swash-Plate Type Variable Displacement Plunger Pump

Theoretical Displacement (SetCapacity)

280 cm3/rev (17.1 in3/rev)

Rated Pressure

34.3 MPa (4970 psi)

Type

Hydraulic Pressure Operated Type

REGULATOR 3-UNIT PUMP

MAIN CONTROL VALVE

Fan Pump

Pilot Pump

Transmission Oil Circulation Pump

Type

Fixed Displacement Swash-Plate Type Variable Displacement Type Gear Pump Plunger Pump

Theoretical Displacement

80 cm3/rev (4.9 in3/rev) 28 cm3/rev (1.7 in3/rev) 14.8 cm3/rev (0.9 in3/ rev)

Maximum Flow Rate (Theoretical Value)

125 L/min (33 US gpm)

Type

Pilot Pressure Operated Type (4-Spools + 5-Spools)

Main Relief SetPressure

Normal: 31.9 MPa at 250 L/min (4630 psi at 66 US gpm)

51.4 L/min (13.6 US gpm)

Fixed Displacement Type Gear Pump

27.1 L/min (7.2 US gpm)

Increases Pressure: 34.3 MPa at 230 L/min (4970 psi at 60.8 US gpm) Overload Relief SetPressure SWING CONTROL VALVE Type

TOKAA90-EN-00

35.3 MPa at 110 L/min (5120 psi at 29 US gpm) (Boom, Arm, Bucket) 11.8 MPa at 110 L/min (1710 psi at 29 US gpm) (Boom Lower (Boom Mode Switch: ON) Pilot Pressure Operated Type (4-Spools)

Main Relief SetPressure

31.9 MPa at 250 L/min (4630 psi at 66.1 US gpm)

Overload Relief SetPressure

35.3 MPa at 110 L/min (Arm)

T1-3-6

SECTION 1 GENERAL Group 3 Component Specifications SWING DEVICE

Type

Two-Stage Reduction Planetary Gear

Reduction Gear Ratio

28.235

Type

Swash-Plate Type, Fixed Displacement Axial Plunger Motor

Theoretical Displacement

210.1 cm3/rev (12.8 in3/rev)

Type

Non Counterbalance Valve Type

Relief Set-Pressure

27.4 MPa at 110 L/min (3970 psi at 29.1 US gpm)

Type

Wet-Type Spring Set Hydraulic Released Multi-Disc Brake

Release Pressure

2.0 to 2.5 MPa (290 to 365 psi)

Type

Three-Stage Reduction Planetary Gear

Reduction Gear Ratio

137.204

Type

Swash-Plate Type Variable Displacement Axial Plunger Motor

Theoretical Displacement (Fast/Slow)

228.6/337.2 cm3/rev (13.9/20.6 in3/rev)

Type

Counterbalance Valve Type

Relief Set-Pressure

36.8 MPa at 120 L/min (5340 psi at 31.7 US gpm)

TRAVEL PARKING BRAKE

Type

Wet-Type Spring Set Hydraulic Released Multi-Disc Brake

RADIATOR FAN MOTOR OIL COOLER FAN MOTOR

Release Starting Pressure Theoretical Displacement Theoretical Displacement

1.37 MPa (200 psi) 48.0 cm3/rev (2.9 in3/rev) 48.0 cm3/rev (2.9 in3/rev)

SWING MOTOR VALVE UNIT SWING PARKING BRAKE TRAVEL DEVICE TRAVEL MOTOR

TRAVEL BRAKE VALVE

TOKAA90-EN-00

T1-3-7

SECTION 1 GENERAL Group 3 Component Specifications CYLINDER Rod Diameter

Boom 160 mm (6 in)

Arm 180 mm (7 in)

Bucket 170 mm (7 in)

Cylinder Bore

230 mm (9 in)

260 mm (10 in)

240 mm (9 in)

Stroke

2210 mm (7 ft 3 in)

2425 mm (7 ft 12 in)

1790 mm (5 ft 11 in)

3605 mm (11 ft 10 in) 2895 mm (9 ft 6 in) Fully Retracted Length 3200 mm (10 ft 6 in) 25 μm or more (984 μin) 25 μm or more (984 μin) 25 μm or more (984 μin) Plating Thickness

TOKAA90-EN-00

T1-3-8

SECTION 1 GENERAL Group 3 Component Specifications FRONT ATTACHMENT PILOT VALVE

Plunger Stroke

TRAVEL PILOT VALVE

Plunger Stroke

Ports 1, 2, 3, 4: 4.6 mm (0.18 in)

5-SPOOL SOLENOID VALVE UNIT

Type

5-Spool Proportional Solenoid Valve

Rated Voltage

DC 24 V

Coil Resistance

22 Ω

Type

2-Spool Proportional Solenoid Valve

Rated Voltage

DC 24 V

Coil Resistance

22 Ω

SIGNAL CONTROL VALVE

Rated Pressure

3.72 MPa

PILOT SHUT-OFF SOLENOID VALVE

Type

ON/OFF Solenoid Valve

Rated Voltage

DC 24 V

Coil Resistance Relief Set-Pressure Relief Set-Pressure Cracking Pressure

48 Ω 21.6 kPa at 44.5 L/min (3.1 psi at 11.8 US gpm) 21.6 kPa at 44.5 L/min (3.1 psi at 11.8 US gpm) 343 kPa at 40 L/min (49.7 psi at 10.6 US gpm)

Full-Flow Filter Suction Filter Pilot Filter Fuel Filter (Stage 1) Pump Transmission Oil Filter Drain Filter

β10>2.0 177 μm (80 mesh) β10≥1.4 5 μm 105 μm 10 μm

2-SPOOL SOLENOID VALVE UNIT

OIL COOLER FAN VALVE RADIATOR FAN VALVE OIL COOLER BYPASS CHECK VALVE FILTER (FILTRATION GRAIN SIZE)

TOKAA90-EN-00

Ports 1, 3: 6.5 mm (0.26 in) Ports 2, 4: 8.0 mm (0.32 in)

T1-3-9

SECTION 1 GENERAL Group 3 Component Specifications Electrical Component BATTERY RELAYS 1, 2

Voltage/Current

24 V/120 A

SAFETY RELAYS 1, 2

Voltage/Current

24 V/180 A

HYDRAULIC OIL TEMPERATURE SENSOR

Operating Temperature

-30 to 120 °C (-22 to 248 °F)

AIR FILTER RESTRICTION SWITCH

Operating Pressure

6.2±0.6 kPa (900±87 psi)

HORN

Voltage/Current

26 V/2.3 A

Sound Pressure

115±5 dB (A) at 2 m

Boom Light

24 V/70 W

Work Light (Left)

24 V/50 W

Work Light (Right)

24 V/50 W

Work Light (Cab Upper)

24 V/50 W

Cab Light

24 V/30 mA

Step Light

24 V/70 W

Cab Rear Light

24 V/70 W

Rear Light

24 V/70 W

Refrigerant

R134 a

Cooling Ability

4.5 kW (6.1 PS) or More

Cool Air Volume

550 m3/h (720 yd3) or More

Heating Ability

5.8 kW (7.9 PS) or More

Warm Air Volume

390 m3/h (510 yd3) or More

Temperature Adjusting System

Electronic Type

Refrigerant Quantity

1250±50 g (3±0.1 lb)

Compressor Oil Quantity

160 cm3 (9.8 in3)

ILLUMINATION

AIR CONDITIONER

TOKAA90-EN-00

T1-3-10

MEMO

TOKAA90-EN-00

MEMO

TOKAA90-EN-00

SECTION 2

SYSTEM CONTENTS Group 1 Controller

Outline..................................................................................... T2-1-1 DLU: Data Logging Unit..................................................... T2-1-3

Group 2 Control System

Group 6 Air Conditioning System

Outline..................................................................................... T2-6-1 Electrical Circuit Diagram.................................................. T2-6-4 Functions of Main Parts..................................................... T2-6-5

Outline..................................................................................... T2-2-1 Engine Control...................................................................... T2-2-6 Pump Control......................................................................T2-2-26 Valve Control (Standard).................................................T2-2-52 Other Control......................................................................T2-2-70

Group 3 Engine System

ECM System........................................................................... T2-3-1

Group 4 Hydraulic System

Outline..................................................................................... T2-4-1 Pilot Circuit............................................................................. T2-4-2 Main Circuit..........................................................................T2-4-12 Transmission Oil Cooling Circuit...................................T2-4-32 Fan Motor Circuit...............................................................T2-4-33

Group 5 Electrical System

Outline..................................................................................... T2-5-1 Main Circuit............................................................................ T2-5-2 Electric Power Circuit (Key Switch: OFF)...................... T2-5-4 Electric Power Circuit (Key Switch: ACC)...................... T2-5-6 Electric Power Circuit (Key Switch: ON)........................ T2-5-8 Starting Circuit (Key Switch: START)............................T2-5-16 Charging Circuit (Key Switch: ON)...............................T2-5-18 Pilot Shut-Off Circuit (Key Switch: ON).......................T2-5-20 Auto Shut-Down Circuit..................................................T2-5-22 Engine Stop Circuit............................................................T2-5-24 Surge Voltage Prevention Circuit.................................T2-5-26 Monitor Circuit....................................................................T2-5-29 Security Circuit....................................................................T2-5-30 Radio Circuit........................................................................T2-5-32 Air Conditioner Circuit.....................................................T2-5-32 Accessory Circuit................................................................T2-5-35 Work Light Circuit..............................................................T2-5-36 Step Light Circuit ..............................................................T2-5-38 Wiper/Washer Circuit........................................................T2-5-40 Cab Light Circuit.................................................................T2-5-44 Sliding Fold-In Ladder Alarm Circuit...........................T2-5-46

TOKAA90-EN-00

KAA90T-2-1

(Blank)

TOKAA90-EN-00

KAA90T-2-2

SECTION 2 SYSTEM Group 1 Controller Outline

fNOTE: DLU: Data Logging Unit

The following controllers are provided in this machine for the control, monitoring, display, and log data communication. Each controller excluding communication controller (9) communicates by using the CAN circuit and sends or receives the required signal.

WIU: Wireless Interface Unit CSU: Contamination Sensing Unit

Controller

Control

MC1(4) MC2(8) ECM(5) Monitor Controller (2)

MC1 (4) controls the engine, pumps, and valves. MC2 (8) controls the lights, wiper, washer, and sliding fold-in ladder alarm. ECM (5) controls the actual engine speed. Monitor controller (2) displays the operating information and alarms on the monitor. Air conditioner controller (7) controls the air conditioner.

Air Conditioner Controller (7) Radio Controller (6) Radio controller (6) controls the radio. Communication Controller Communication controller (9) sends the mails and operating information. (9) DLU(11) DLU (11) controls for the communication status monitoring and operating information maintenance. WIU (12) (Option) WIU (12) downloads log data from DLU (11) and records them in its built-in memory. CSU (13) (Option) CSU (13) monitors the amount of contaminant (metal particles) with the contamination sensors (option) in the drain circuits.

Comment on Control T2-2 T2-5 T2-3 T5-2 T2-6, T5-8 T2-5 T5-9 T2-1 -

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

10 8

1 2

9 13

d TKAB-02-01-005

Power CAN

Body CAN

Monitoring CAN

1234-

Monitor Monitor Controller MPDr. MC1

5678-

ECM Radio Controller Air Conditioner Controller MC2

9101112-

Communication Controller GPS Antenna DLU WIU(OP)

13- CSU(OP)

TOKAA90-EN-00

T2-1-1

DLU-CAN

SECTION 2 SYSTEM Group 1 Controller CAN Circuit CAN (Controller Area Network) is ISO Standards of the serial communication protocol. Four networks (CAN bus (3)) in the following are equipped for this machine.  Power CAN (4) is mainly used for the engine control.  Body CAN (5) is mainly used for the accessories.  Monitoring CAN (7) is mainly used for display and log data communication.  DLU-CAN (8) is used for communication between DLU (17) and WIU (15) (option). CAN bus (3) consists of two wire harnesses, CAN-H (High) (1) and CAN-L (Low) (2). Each controller judges the CAN bus (3) level due to the potential difference between CAN-H (High) (1) and CAN-L (Low) (2). Each controller arranges potential difference of CAN bus (3) and sends the signal and data to other controllers. Termination resistors (120 Ω) (9) are installed to both ends of CAN bus (3).

2 TKEB-02-05-017

12-

CAN-H (High) CAN-L (Low)

CAN Bus

9 14

12 11

5 13

21 14 14

15 20

16 7

45789-

Power CAN Body CAN Monitoring CAN DLU CAN MPDr.

TOKAA90-EN-00

1011121314-

Monitor Controller Monitor Monitor Control Unit Information Control Unit Termination Resistor (120 Ω)

1516171819-

T2-1-2

WIU (OP) CSU (OP) DLU Radio Controller Air Conditioner Controller

TKAA90-02-01-001 20- MC2 21- MC1 22- ECM

SECTION 2 SYSTEM Group 1 Controller DLU: Data Logging Unit Outline  Monitor System Monitoring DLU (11) monitors communication status with the connected units and records abnormality if any.

 FMS Communication (Option) DLU (11) communicates with FMS (Fleet Management System). DLU (11) sends alarm information to FMS simultaneously when warning.

 Operating Hour Control DLU (11) incorporates the built-in clock. The built-in clock is corrected by using the GPS receiving part of communication controller (9).

 Satellite Communication Terminal (Option)/Mobile Communication Terminal (Option) DLU (11) sends the log data recorded in DLU (11) to the satellite communication terminal or mobile communication terminal.

 Taking-in Basic data DLU (11) takes in the data related to ECM from Power CAN (a).  Warning Detection DLU (11) records warning information with stamped time.  Operating Condition Detection DLU (11) processes the data every 30 minutes.

10 8

1 2

9 13

d TKAB-02-01-005

Power CAN

Body CAN

Monitoring CAN

1234-

Monitor Monitor Controller MPDr. MC1

5678-

ECM Radio Controller Air Conditioner Controller MC2

9101112-

Communication Controller GPS Antenna DLU WIU(OP)

13- CSU(OP)

TOKAA90-EN-00

T2-1-3

DLU-CAN

SECTION 2 SYSTEM Group 1 Controller (Blank)

TOKAA90-EN-00

T2-1-4

SECTION 2 SYSTEM Group 2 Control System Outline MC1 (main controller 1) is used in order to control the machine operations. Signals from the engine control dial, various sensors, and various switches are sent to MC1 and processed in the logic circuit. MC1 sends the signal equivalent to the target engine speed to ECM by using CAN communication in order to control the engine. (Refer to SYSTEM/Controller.) In addition, MC1 drives the solenoid valve units and pump control solenoid valves in order to control the pump and valve.

TOKAA90-EN-00

T2-2-1

SECTION 2 SYSTEM Group 2 Control System Engine Control Input Signal Engine Control Dial Power Mode Switch Auto-Idle Switch Travel Mode Switch Key Switch Pilot Shut-Off Switch Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor Pump 3 Delivery Pressure Sensor Pump 1 Regulator Pressure Sensor Pump 2 Regulator Pressure Sensor Pump 3 Regulator Pressure Sensor Pressure Sensor (Boom Raise) Pressure Sensor (Boom Lower) Pressure Sensor (Arm Roll-In) Pressure Sensor (Arm Roll-Out) Pressure Sensor (Bucket Roll-In) Pressure Sensor (Bucket Roll-Out) Pressure Sensor (Swing)

                  

Pressure Sensor (Travel) Pressure Sensor (Auxiliary) (OP) Hydraulic Oil Temperature Sensor

  

Coolant Temperature Sensor  Engine Speed Sensor  Boost Pressure Sensor 

Output Signal Engine Control (ECM) Engine Control Dial Control Power Mode Switch Control ECO Mode Control PWR Mode Control HP Mode Control ECO Control Travel Mode Control Auto-Idle Control Engine Speed Slow Down Control

MC1

ECM CAN0

MPDr. Work Mode

 

Monitor Controller

fNOTE: OP: Option

TOKAA90-EN-00

T2-2-2

SECTION 2 SYSTEM Group 2 Control System Pump Control Input Signal Engine Control Dial Power Mode Switch Auto-Idle Switch Travel Mode Switch Key Switch Pilot Shut-Off Switch Pump Regulator Pressure Learning Switch Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor Pump 3 Delivery Pressure Sensor Pump 1 Regulator Pressure Sensor Pump 2 Regulator Pressure Sensor Pump 3 Regulator Pressure Sensor Pressure Sensor (Boom Raise) Pressure Sensor (Boom Lower) Pressure Sensor (Arm Roll-In) Pressure Sensor (Arm Roll-Out) Pressure Sensor (Bucket Roll-In) Pressure Sensor (Bucket Roll-Out) Pressure Sensor (Swing) Pressure Sensor (Travel)

                   MC1  

Pressure Sensor (Auxiliary) (OP) Hydraulic Oil Temperature Sensor Boost Temperature Sensor

  

Fuel Temperature Sensor Coolant Temperature Sensor Engine Speed Sensor

 

ECM

 CAN0

MPDr. Work Mode

 

Monitor Controller CAN1

Ambient Temperature Sensor

Air  Conditioner Controller

fNOTE: OP: Option *: This control is for only the machine with the optional parts equipped.

TOKAA90-EN-00

T2-2-3

Output Signal Pump Control (Pump Control Solenoid Valve) Speed Sensing Control Output Power Control Engine Protection Control Swing High Pressure Power Decrease Control Overheat Prevention Control * Attachment Operation Pump Control Fan Pump Flow Rate Control Pump Learning Control Pump 1 Flow Rate Control Pump 2 Flow Rate Control Pump 3 Flow Rate Control

SECTION 2 SYSTEM Group 2 Control System Valve Control, Other Control Input Signal Engine Control Dial Power Mode Switch Auto-Idle Switch Travel Mode Switch Key Switch Pilot Shut-Off Switch Power Digging Switch Boom Mode Switch Fan Reverse Rotation Switch Pump 1 Delivery Pressure Sensor Pump 2 Delivery Pressure Sensor Pump 3 Delivery Pressure Sensor Pump 1 Regulator Pressure Sensor Pump 2 Regulator Pressure Sensor Pump 3 Regulator Pressure Sensor Pressure Sensor (Boom Raise) Pressure Sensor (Boom Lower) Pressure Sensor (Arm Roll-In) Pressure Sensor (Arm Roll-Out) Pressure Sensor (Bucket Roll-In) Pressure Sensor (Bucket Roll-Out) Pressure Sensor (Swing) Pressure Sensor (Travel) Pressure Sensor (4-Spool Side) Pressure Sensor (5-Spool Side) Pressure Sensor (Auxiliary) (OP) Lubrication Mode Selection Switch Hydraulic Oil Temperature Sensor Boom Bottom Pressure Sensor Overload Alarm Switch (OP) Coolant Temperature Sensor

                             

Output Signal Valve Control (Standard) (4-Spool/2-Spool Solenoid Valve Units) Power Digging Control Auto-Power Lift Control Travel Motor Displacement Angle Control Pressure Rising Selection Control When Traveling Boom Mode Control Bypass Cut Valve Control During Boom Lowering Arm 2 Flow Rate Control Fan Reverse Rotation Control Other Control Work Mode Control Auto Shut-Down Control Auto-Lubrication Control (Quicklub Lubrication System) * Auto-Lubrication Control (Centro Matic System) Hydraulic Oil Overheat Alarm Control * Swing Alarm Control * Travel Alarm Control * Overload Alarm Control

MC1

 ECM

CAN0 MPDr. Work Mode

 

Monitor Controller

fNOTE: OP: Option *: This control is for only the machine with the optional parts equipped.

TOKAA90-EN-00

T2-2-4

SECTION 2 SYSTEM Group 2 Control System (Blank)

TOKAA90-EN-00

T2-2-5

SECTION 2 SYSTEM Group 2 Control System Engine Control The engine control consists of the followings.  Engine Control Dial Control  Power Mode Switch Control  ECO Mode Control  PWR Mode Control  HP Mode Control  ECO Control  Travel Mode Control  Auto-Idle Control  Engine Speed Slow Down Control

TOKAA90-EN-00

T2-2-6

SECTION 2 SYSTEM Group 2 Control System Engine Control System Layout 2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-001

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

23- Pump 2 Regulator Pressure Sensor 24- Pump 2 Control Solenoid Valve 25- Pump 2 Delivery Pressure Sensor 26- Pump 1 Regulator Pressure Sensor 27- Pump 1 Control Solenoid Valve 28- Pump 1 Delivery Pressure Sensor 29- Pump 3 Regulator Pressure Sensor 30- Pump 3 Control Solenoid Valve

T2-2-7

31- Pump 3 Delivery Pressure Sensor 32- Auto Shut-Down Signal 33- Travel Mode Switch 34- Slow Speed Position 35- Fast Speed Position 36- Auto-Idle Switch 37- Power Mode Switch 38- Engine Control Dial 39- Key Switch 40- Pilot Shut-Off Switch 41- MC2 42- Sliding Fold-In Ladder Relay

SECTION 2 SYSTEM Group 2 Control System Engine Control Dial Control A

Purpose: The engine control dial control controls the engine speed according to the rotation angle of engine control dial (38).

Operation: 1. MC1 (13) receives the signals of the rotation angle (the required engine speed) of engine control dial (38). MC1 (13) sends the signal equivalent to the target engine speed according to the received signals to ECM (18) by using CAN communication (17). 2. ECM (18) controls the engine speed according to the received signal by using CAN communication (17).

TOKAA90-EN-00

F C ABC-

T2-2-8

Engine Speed Engine Control Dial Position Slow Idle Position

D DEF-

Fast Idle Position Fast Idle Speed Slow Idle Speed

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-002

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-9

SECTION 2 SYSTEM Group 2 Control System Power Mode Switch Control Purpose: The power mode switch control shifts the power mode (ECO/PWR/HP mode) by operating power mode switch (37). Operation: 1. MC1 (13) receives the signal from power mode switch (37). 2. MC1 (13) shifts the power mode according to the setting of “Power Mode Selection“ and ”Power Mode Memory Selection” on MPDr. (14) by pushing power mode switch (37). (Refer to the table.) 3. According to the power mode, MC1 (13) sends the signal equivalent to the target engine speed to ECM (18) by using CAN communication (17). 4. ECM (18) controls the engine speed according to the received signal by using CAN communication (17). 5. At the same time, MC1 (13) sends the control mode of power mode to monitor controller (15) by using CAN communication (17). 6. Monitor controller (15) displays the control mode of power mode on monitor (16). Power Mode ON/OFF Setting

Power mode at the moment when key switch is turned OFF

ECO, PWR Mode Selection

1 2 3

ECO Mode Keeping PWR Mode Keeping ECO, PWR, HP Mode Selection (Default)

HP Mode Keeping

ECO PWR ECO PWR HP -

TOKAA90-EN-00

T2-2-10

Power mode when key switch is ON next time Power Mode Memory Power Mode Memory Selection: ON (Default) Selection: OFF ECO ECO PWR PWR ECO ECO PWR PWR ECO ECO PWR PWR PWR HP HP HP

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-004

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-11

SECTION 2 SYSTEM Group 2 Control System ECO Mode Control A

Purpose: The ECO (Economy) mode control lowers the engine speed in order to reduce fuel consumption.

E F

Operation: 1. When all following conditions exist, the ECO mode control is activated.  Required engine speed signal from engine control dial (38): The engine speed is faster than the ECO mode speed.  Power mode switch (37): ECO mode position

G C

2. When the ECO mode control is activated, MC1 (13) sends the signal equivalent to the ECO mode speed to ECM (18) by using CAN communication (17).

ABCD-

3. ECM (18) sets the engine speed to the ECO mode speed (1700 min-1)

TOKAA90-EN-00

T2-2-12

Engine Speed Engine Control Dial Position Slow Idle Position Fast Idle Position

D EFG-

Fast Idle Speed (1950 min-1) ECO Mode Speed (1700 min-1) Slow Idle Speed

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-005

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-13

SECTION 2 SYSTEM Group 2 Control System PWR Mode Control Purpose: The PWR (Power) mode control is used during normal operation and sets the fast idle engine speed to 1800 min-1.

A E F

Operation: 1. When all following conditions exist, the PWR mode is activated.  Work Mode: Digging Mode  Required engine speed signal from engine control dial (38): The engine speed is set faster than the PWR mode speed.  Power mode switch (37): PWR mode position 2. When the PWR mode is activated, MC1 (13) sends the signal equivalent to the PWR mode speed to ECM (18) by using CAN communication (17).

G C ABCDE-

3. ECM (18) sets the engine speed to the PWR mode speed (1800 min-1).

fNOTE: The PWR mode control can be made operable or inoperable by MPDr. (14).

TOKAA90-EN-00

T2-2-14

Engine Speed Engine Control Dial Position Slow Idle Position Fast Idle Position Fast Idle Speed (1950 min-1)

D F-

PWR Mode Speed (1800 min) Slow Idle Speed

G-

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-006

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-15

SECTION 2 SYSTEM Group 2 Control System HP Mode Control Purpose: The HP (High Power) mode control does not limit the engine speed. When a little more engine output power is required during arm roll-in operation for deeply digging, the HP mode control is used.

A E F

Operation: 1. When all following conditions exist, the HP mode is activated.  Work Mode: Digging Mode  Power mode switch (37): HP mode position  Required engine speed signal from engine control dial (38): The engine speed is set faster than the PWR mode speed (1800 min-1). 2. MC1 (13) does not limit the target engine speed. MC1 (13) sends the signal equivalent to the engine control dial (38) to ECM (18) by using CAN communication (17).

G C ABCD-

3. ECM (18) controls the engine speed according to the received signal by using CAN communication (17). 4. MC1 (13) controls the pump delivery flow rate according to the target engine speed and the engine load. (Refer to Speed Sensing Control.)

TOKAA90-EN-00

T2-2-16

Engine Speed Engine Control Dial Position Slow Idle Position Fast Idle Position

D EFG-

Fast Idle Speed (1950 min-1) PWR Mode Speed (1800 min-1) Slow Idle Speed

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-007

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-17

SECTION 2 SYSTEM Group 2 Control System ECO Control A

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.

Operation: 1. When all following conditions exist and all the control levers are set to the neutral position [all pressure sensors (2 to 9, 12): OFF], MC1 (13) sends the signal to ECM (18) by using CAN communication (17) after one second.

 Engine control dial (38): Fast Idle Position  Power mode switch (37): HP or PWR

C ABCD-

Engine Speed Engine Control Dial Position Slow Idle Position Fast Idle Position

D EFG-

Fast Idle Speed (1950 min-1) ECO Speed Slow Idle Speed

2. ECM (18) reduces the engine speed by 100 min-1 from the fast idle speed.

fNOTE: The ECO control is deactivated by MPDr. (14)

temporarily or completely. The ECO control is activated again when key switch (39) is turned OFF with the ECO control deactivated temporarily. The ECO control is always dectivated with the ECO control deactivated completely. (ECO Control Suspend)

TOKAA90-EN-00

fNOTE: When the engine speed is set slower than the

fast idle speed by 100 min-1 by engine control dial (38), 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. (14). (PWR Mode Speed)

T2-2-18

SECTION 2 SYSTEM Group 2 Control System 2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-003

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-19

SECTION 2 SYSTEM Group 2 Control System Travel Mode Control Purpose: The travel mode control decreases the fast idle engine speed to 1800 min-1, when the machine travels at the HP mode. Therefore, this control decreases the travel speed and protects the travel motor.

A E F

Operation: 1. When all following conditions exist, MC1 (13) sends the restricted engine speed signal at 1800 min-1 to ECM (18).  Required engine speed signal from engine control dial (38): over 1800 min-1  Power mode switch (37): HP mode position  Pressure Sensor (Travel) (9): Outputting signal

2. ECM (18) sets the engine speed to 1800 min-1. 3. MC1 (13) decreases the travel speed so that the pump delivery flow rate can be set according to the restricted engine speed. (Refer to Speed Sensing Control.)

TOKAA90-EN-00

ABCDE-

T2-2-20

Engine Speed Engine Control Dial Position Slow Idle Position Fast Idle Position Fast Idle Speed

D FG-

1800 min-1 Slow Idle Speed

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-041

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-21

SECTION 2 SYSTEM Group 2 Control System Auto-Idle Control A

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.

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

 Auto-idle switch (36): ON position  Control lever: All control levers are held in the neutral position [pressure sensors (2 to 9, 12): OFF] beyond 3.5 seconds 2. When the auto-idle control is activated, MC1 (13) sends the signal equivalent to the auto-idle speed to ECM (18) by using CAN communication (17).

G C ABCD-

3. ECM (18) changes the engine speed into the autoidle speed. 4. When any one of the following condition exists, the auto-idle control is deactivated.  Control lever: Any control lever is operated [pressure sensors (2 to 9, 12): ON]  When power mode switch (37) is operated  When engine control dial (38) is operated 5. MC1 (13) returns the signal sending to ECM (18) into the signal equivalent to the target engine speed set by engine control dial (38) immediately.

fNOTE: The auto-idle speed can be adjusted by MPDr. (14). (AI Speed)

TOKAA90-EN-00

T2-2-22

Engine Speed Engine Control Dial Position Slow Idle Position Fast Idle Position

D EFG-

Fast Idle Speed Auto-Idle Speed Slow Idle Speed

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-008

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-23

SECTION 2 SYSTEM Group 2 Control System 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 shut-down control is performed. Therefore, the loads of the engine and hydraulic actuator can be reduced.

Operation: 1. MC1 (13) saves the engine speed at the moment when the auto shut-down control is performed. 2. MC1 (13) sends the signal that the engine speed gradually reduces from the saved engine speed to ECM (18) by using CAN communication (17).

3. ECM (18) reduces the engine speed to the slow idle speed according to CAN communication (17). 4. Then, the auto shut-down control stops the engine. (Refer to Auto Shut-Down Control.)

TOKAA90-EN-00

AB-

T2-2-24

Engine Speed Time

C-

Slow Idle Speed

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

39 38

17 41

37 13 36

21 22

34 33 20

31 30 29

28 27 26

25 24 23 TKAA90-02-02-010

123456789-

TOKAA90-EN-00

12- Pressure Sensor (Auxiliary) (OP) 13- MC1 14- MPDr. 15- Monitor Controller 16- Monitor 17- CAN 18- ECM 19- Coolant Temperature Sensor 20- Engine 21- Boost Pressure Sensor 22- Engine Speed Sensor

T2-2-25

SECTION 2 SYSTEM Group 2 Control System Pump Control The pump control consists of the followings.  Speed Sensing Control  Output Power Control  Engine Protection Control  Swing High Pressure Power Decrease Control  Overheat Prevention Control  * Attachment Operation Pump Control  Fan Pump Flow Rate Control  Pump Learning Control  Pump 1 Flow Rate Control  Pump 2 Flow Rate Control  Pump 3 Flow Rate Control

fNOTE: * This control is for only the machine with the optional parts equipped.

TOKAA90-EN-00

T2-2-26

SECTION 2 SYSTEM Group 2 Control System Pump Control System Layout 2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-011

Hydraulic Oil Temperature Sensor 2- Pressure Sensor (Boom Raise) 3- Pressure Sensor (Boom Lower) 4- Press Sensor (Arm Roll-In) 5- Press Sensor (Arm Roll-Out) 6- Pressure Sensor (Bucket RollIn) 7- Pressure Sensor (Bucket RollOut) 8- Pressure Sensor (Swing) 9- Pressure Sensor (Travel) 12- Pressure Sensor (Auxiliary) (OP)

TOKAA90-EN-00

131415161718192021222324-

MC1 MPDr. Monitor Controller Monitor CAN ECM Coolant Temperature Sensor Boost Temperature Sensor Fuel Temperature Sensor Engine Speed Sensor Engine Pump 2 Regulator Pressure Sensor 25- Pump 2 Control Solenoid Valve

26- Pump 2 Delivery Pressure Sensor 27- Pump 1 Regulator Pressure Sensor 28- Pump 1 Control Solenoid Valve 29- Pump 1 Delivery Pressure Sensor 30- Pump 3 Regulator Pressure Sensor 31- Pump 3 Control Solenoid Valve 32- Pump 3 Delivery Pressure Sensor 33- Fan Pump Control Solenoid Valve

T2-2-27

34- Air Conditioner Controller 35- Ambient Temperature Sensor 36- Pump Regulator Pressure Learning Switch 37- Auto-Idle Switch 38- Power Mode Switch 39- Engine Control Dial 40- Key Switch 41- Pilot Shut-Off Switch 42- Fan Pump

SECTION 2 SYSTEM Group 2 Control System Speed Sensing Control Purpose: The speed sensing control controls the main pump delivery flow rate 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.

HP Mode Q

Operation: 1. The target engine speed can be set by engine control dial (39). 2. ECM (18) receives the signal from engine speed sensor (22). 3. ECM (18) calculates it and sends the actual engine speed to MC1 (13) by using CAN communication (17).

4. MC1 (13) calculates the difference in the speed between the target engine speed and actual engine speed that is recieved through CAN communication (17) from ECM (18).

T111-05-02-004

PWR/ECO Mode Q

5. If the actual engine speed is faster than the target engine speed, MC1 (18) judges that the load to the engine is light. MC1 (18) performs the control so that the pump delivery flow rate can increase according to the difference between the actual engine speed and the target engine speed. When the power mode switch is in the PWR or ECO position, the control to increase the pump delivery flow rate is not performed. 6. MC1 (13) sends the signals to the pump control solenoid valves (28, 25, 31).

7. The pump control solenoid valves (28, 25, 31) deliver the pilot pressure according to the signals to the regulators, and controls the pump delivery flow rate.

T166-02-01-014 P-

8. On the contrary, if the engine load is heavy and the actual engine speed is slower than the target engine speed, the pump displacement angle is reduced so that the pump flow rate will be reduced. Therefore, the engine load is reduced and the engine stall is prevented.

TOKAA90-EN-00

T2-2-28

Pressure

Q-

Flow Rate

SECTION 2 SYSTEM Group 2 Control System 2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-012

TOKAA90-EN-00

131415161718192021222324-

T2-2-29

SECTION 2 SYSTEM Group 2 Control System Output Power Control Purpose: The output power control effectively utilizes the engine output power by controlling the delivery flow rate of pumps 1, 2, 3 so that allocated sum of pumps 1, 2, 3 driving torque does not exceed the engine output torque. Operation: 1. Normally, when pumps 1, 2, and 3 are operated, the delivery pressure is not same. 2. A pump of higher delivery pressure carries higher load and a pump of lower delivery pressure carries lower load. 3. The pump delivery pressure sensors (29, 26, 32) and pump regulator pressure sensors (27, 24, 30) detect this state and send the signals to MC1 (13). 4. MC1 (13) calculates the target displacement angles of pumps 1, 2, and 3 so that allocated sum of pumps 1, 2, 3, and fan pump driving torque does not exceed the engine output torque by using the signals from the pump delivery pressure sensors (29, 26, 32) and pump regulator pressure sensors (27, 24, 30). 5. MC1 (13) compares the pump displacement angle calculated by the pump regulator pressure sensors (27, 24, 30) with the target pump displacement angle. 6. MC1 (13) monitors the actual pump displacement angle at the larger load side for comparison with the target pump displacement angle, and drives the pump control solenoid valve of the pump at the larger load side for the difference with the target angle. Then, MC1 (13) increases the pump delivery flow rate at the larger load side.

fNOTE: 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 T2-2-50.)

TOKAA90-EN-00

T2-2-30

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-013

TOKAA90-EN-00

131415161718192021222324-

T2-2-31

SECTION 2 SYSTEM Group 2 Control System Engine Protection Control Purpose: When ECM (18) detects abnormality, the engine protection control decreases the pump delivery flow rate and pump driving torque. Then, the engine is prevented from damage. 1. When any one of the following conditions exists, ECM (18) sends the abnormal signal to MC1 (13) by using CAN communication (17).  Coolant Temperature: High  Intake Manifold Temperature: High  Engine Oil Pressure: Low  Coolant Level: Low 2. When MC1 (13) receives the abnormal signal, MC1 (13) sends the pump driving torque reduction request signal to the pump control solenoid valves (28, 25, 31). 3. The pump control solenoid valves (28, 25, 31) decreases the displacement angle of each pump, and decreases the pump delivery flow rate and pump driving torque. Then, the engine load is reduced. 4. At the same time, MC1 (13) sends the signal to monitor controller (15). Monitor controller (15) displays the alarm on monitor (16) and sounds the buzzer.

TOKAA90-EN-00

T2-2-32

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-045

TOKAA90-EN-00

131415161718192021222324-

T2-2-33

SECTION 2 SYSTEM Group 2 Control System Swing High Pressure Power Decrease Control Purpose: The swing high pressure power decrease control reduces the pump 3 delivery flow rate when performing the swing single operation or combined operation of boom lower and swing, and reduces fuel consumption. Operation: 1. When all following conditions exist, MC1 (13) activates the pump 3 control solenoid valve (31).  Swing pilot pressure: High  Outputting signal from pressure sensor (swing) (8) or outputting signal from both pressure sensor (boom lower) (3) and pressure sensor (swing) (8) are detected.  Pump 3 delivery pressure: High 2. The pump 3 control solenoid valve (31) delivers the pilot pressure according to the signal to the regulator and reduces the pump 3 delivery flow rate.

TOKAA90-EN-00

T2-2-34

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-015

TOKAA90-EN-00

131415161718192021222324-

T2-2-35

SECTION 2 SYSTEM Group 2 Control System Overheat Prevention Control Purpose: The overheat prevention control prevents engine overheating by reducing the pump maximum flow rate and pump driving torque when the coolant or hydraulic oil temperature exceeds the specified value. Operation:  Control by Coolant Temperature 1. ECM (18) sends the signal of coolant temperature sensor (19) to MC1 (13) by using CAN communication (17).

Control by Coolant Temperature Q

2. MC1 (13) calculates the target pump displacement angle, which reduces the pump driving torque by 7%, by using the signals from the pump delivery pressure sensors (29, 26, 23) when the coolant temperature becomes 99 °C or higher. 3. MC1 (13) compares the pump displacement angle calculated by the signal of the pump regulator pressure sensors (27, 24, 30) with the target pump displacement angle.

P Control by Hydraulic Oil Temperature Q

4. MC1 (13) monitors the actual pump displacement angle for comparison with the target pump displacement angle, and activates the pump control solenoid valves (28, 25, 31), decreases the pump displacement angle, and decreases the pump driving torque.  Control by Hydraulic Oil Temperature 1. MC1 (13) receives the signal from the hydraulic oil temperature sensor (1).

P-

3. MC1 (13) compares the pump displacement angle calculated by the signal of the pump regulator pressure sensors (27, 24, 30) with the target pump displacement angle. 4. MC1 (13) monitors the actual pump displacement angle for comparison with the target pump displacement angle, and activates the pump control solenoid valves (28, 25, 31), decreases the pump displacement angle, and decreases the pump maximum flow rate and pump driving torque.

fNOTE: When the following conditions are met, the overheat prevention control is terminated.

 Coolant Temperature: 95 °C or less  Hydraulic Oil Temperature: 95 °C or less TOKAA90-EN-00

T2-2-36

Pressure

Q-

Flow Rate

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-016

TOKAA90-EN-00

131415161718192021222324-

T2-2-37

SECTION 2 SYSTEM Group 2 Control System Attachment Operation Pump Control (Option) Purpose: The attachment operation pump control limits the upper limit of the maximum pump 2 flow rate when operating the attachment. Therefore, this control controls the optimum flow rate for the attachment. Operation: 1. Select ATT Mode of Work Mode on the monitor. 2. When the breaker (attachment pilot valve) is operated, pressure sensor (auxiliary) (12) (option) detects the attachment pilot pressure and sends the signal to MC1 (13). 3. MC1 (13) activates the pump 2 control solenoid valve (25) until the pump 2 displacement angle decreases to the pump maximum flow rate displacement position commanded by the attachment mode. Then, MC1 (13) keeps the displacement angle.

fNOTE: As the attachment is controlled by the auxiliary

spool at the 5-spool in the control valve, only the pump 2 maximum flow rate is controlled.

fNOTE: As returning oil from the breaker does not flow

through the oil cooler but directly flows to the hydraulic oil tank, the hydraulic oil temperature increases. In order to prevent the hydraulic oil temperature from increasing, MC1 (13) activates the pump 1 flow rate control solenoid valve (28) and increases delivery flow rate of pump 1 when operating the breaker. Consequently, as oil amount flowing to the oil cooler increases, increase of the hydraulic oil temperature is controlled, and the engine overheating is prevented when operating the breaker.

TOKAA90-EN-00

T2-2-38

SECTION 2 SYSTEM Group 2 Control System 2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-017

TOKAA90-EN-00

131415161718192021222324-

T2-2-39

SECTION 2 SYSTEM Group 2 Control System Fan Pump Flow Rate Control Purpose: The fan pump flow rate control controls the fan pump delivery flow rate according to the boost temperature, coolant temperature, hydraulic oil temperature, fuel temperature, and ambient temperature. The fan pump flow rate control prevents the fan pump delivery flow rate from decreasing when the engine speed is low while the air conditioner is ON. Therefore, the fan rotation speed is controlled to the optimum temperature for oil cooler, radiator, intercooler, and air conditioner condenser. Operation:  Air Conditioner Switch: OFF 1. ECM (18) sends the signals of fuel temperature sensor (21) and coolant temperature sensor (19) to MC1 (13) by using CAN communication (17). 2. The hydraulic oil temperature sensor (1) and boost temperature sensor (20) send the signals to MC1 (13). 3. MC1 (13) calculates the fan rotation speed by using the received signals. 4. MC1 (13) sends the highest output signal in the calculated fan rotation speed to the fan pump control solenoid valve (33) and controls the fan pump delivery flow rate. 5. Therefore, the fan rotation speed is properly controlled.

TOKAA90-EN-00

T2-2-40

SECTION 2 SYSTEM Group 2 Control System 2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-018

TOKAA90-EN-00

131415161718192021222324-

T2-2-41

SECTION 2 SYSTEM Group 2 Control System  Air Conditioner Switch: ON 1. ECM (18) sends the signals of fuel temperature sensor (21) and coolant temperature sensor (19) to MC1 (13) by using CAN communication (17). 2. Air conditioner controller (34) sends the signal of ambient temperature sensor (35) to MC1 (13). 3. The hydraulic oil temperature sensor (1) and boost temperature sensor (20) send the signals to MC1 (13). 4. Engine control dial (39) sends the target engine speed signal to MC1 (13). 5. MC1 (13) calculates the fan rotation speed by using the received signals. 6. MC1 (13) sends the highest output signal in the calculated fan rotation speed to the fan pump control solenoid valve (33) and controls the fan pump delivery flow rate. 7. The fan rotation speed is properly controlled regardless of the engine speed.

TOKAA90-EN-00

T2-2-42

SECTION 2 SYSTEM Group 2 Control System 2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-019

TOKAA90-EN-00

131415161718192021222324-

T2-2-43

SECTION 2 SYSTEM Group 2 Control System Pump Learning Control Purpose: The pump learning control records the current and control pressure, which are the basic parameters of the pump control when activating the pump control solenoid valves (28, 25, 31). This control controls to sufficient performance of each pump. Operation: 1. When the following conditions exist and the pump regulator pressure learning switch (36) in the rear console is turned to the pump learning side (opposite side of E), MC1 (13) activates the pump control solenoid valves (28, 25, 31).  Engine (23): Running  Engine control dial (39): Fast Idle speed Position  Auto-idle switch (37): OFF  Power mode switch (38): HP mode  Pressure sensor: No outputting signal (the control lever is in the neutral position)  Hydraulic Oil Temperature: 50±5 °C  Pilot shut-off switch (41): LOCK Position 2. The spools of the pump control solenoid valves (28, 25, 31) are operated. 3. The pump regulator pressure sensors (27, 24, 30) detect control pressure of the pump control solenoid valves (28, 25, 31), and send the signals in response to each pressure to MC1 (13). 4. MC1 (13) records the current and control pressure while activating the pump control solenoid valves (28, 25, 31). Therefore, the pump control is optimized. IMPORTANT: When the following work has been performed, perform the pump learning. (Refer to Technical Manual/Troubleshooting.)  When the pump, pump regulator, pump control solenoid valves (28, 25, 31) have been replaced  When MC1 (13) has been replaced

fNOTE: The pump learning is not necessary to perform

the pump learning when the battery has been replaced.

TOKAA90-EN-00

T2-2-44

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-020

TOKAA90-EN-00

131415161718192021222324-

T2-2-45

SECTION 2 SYSTEM Group 2 Control System Pump 1 Flow Rate Control Q

Purpose: The pump 1 flow rate control controls the pump 1 flow rate which is required according to each stroke of the boom, arm, bucket, and travel control levers. Therefore, the fuel consumption is reduced. Operation: 1. When the control lever is operated, MC1 (13) receives the signals from pressure sensors (boom raise (2), boom lower (3), arm roll-out (5), arm roll-in (4), bucket roll-in (6), bucket roll-out (7), and travel (9)).

A A-

2. MC1 (13) activates the pump 1 control solenoid valve (28) according to the control lever stroke and controls the pump 1 flow rate.

TOKAA90-EN-00

T2-2-46

Control Level Operation

Q-

Flow Rate

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-022

TOKAA90-EN-00

131415161718192021222324-

T2-2-47

SECTION 2 SYSTEM Group 2 Control System Pump 2 Flow Rate Control Q

Purpose: The pump 2 flow rate control controls the pump 2 flow rate which is required according to each stroke of the levers (or pedal) of the boom, arm, bucket, travel, and auxiliary (option). Therefore, the fuel consumption is reduced. Operation: 1. When the control lever is operated, MC1 (13) receives the signals from pressure sensors (boom raise (2), boom lower (3), arm roll-out (5), arm roll-in (4), bucket roll-in (6), bucket roll-out (7), travel (9), and auxiliary (12)).

A A-

2. MC1 (13) activates the pump 2 control solenoid valve (25) according to the control lever stroke and controls the pump 2 flow rate.

TOKAA90-EN-00

T2-2-48

Control Level Operation

Q-

Flow Rate

SECTION 2 SYSTEM Group 2 Control System

2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-023

TOKAA90-EN-00

131415161718192021222324-

T2-2-49

SECTION 2 SYSTEM Group 2 Control System Pump 3 Flow Rate Control Q

Purpose: The pump 3 flow rate control controls the pump 3 flow rate which is required according to each stroke of the boom, arm, bucket, and swing control levers. Therefore, the fuel consumption is reduced. Operation: 1. When the control lever is operated, MC1 (13) receives the signals from pressure sensors (boom raise (2), boom lower (3), arm roll-out (5), arm roll-in (4), bucket roll-in (6), bucket roll-out (7), and swing (8)).

A A-

2. MC1 (13) activates the pump 3 control solenoid valve (31) according to the control lever stroke and controls the pump 3 flow rate.

TOKAA90-EN-00

T2-2-50

Control Level Operation

Q-

Flow Rate

SECTION 2 SYSTEM Group 2 Control System 2 3 4 5 6 7 8 9 12

40 39

37 36

35 19

34 23 20

32 31 30

29 28 27

26 25 24 TKAB-02-02-024

TOKAA90-EN-00

131415161718192021222324-

T2-2-51

SECTION 2 SYSTEM Group 2 Control System Valve Control (Standard) The valve control consists of the followings.  Power Digging Control  Auto-Power Lift Control  Travel Motor Displacement Angle Control  Pressure Rising Selection Control When Traveling  Boom Mode Control  Bypass Cut Valve Control During Boom Lowering  Arm 2 Flow Rate Control  Fan Reverse Rotation Control

TOKAA90-EN-00

T2-2-52

SECTION 2 SYSTEM Group 2 Control System 14

Valve Control (Standard) System Layout

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52

37 TKAB-02-02-025

1234567891011121314-

Hydraulic Oil Temperature Sensor Pressure Sensor (Boom Raise) Pressure Sensor (Boom Lower) Press Sensor (Arm Roll-In) Press Sensor (Arm Roll-Out) Pressure Sensor (Bucket Roll-In) Pressure Sensor (Bucket RollOut) Pressure Sensor (Swing) Pressure Sensor (Travel) Pressure Sensor (4-Spool Side) Pressure Sensor (5-Spool Side) Pressure Sensor (Auxiliary) (OP) MC1 MPDr.

TOKAA90-EN-00

15161718192021222324-

2526-

Monitor Controller Monitor ECM Engine Radiator Fan Reverse Rotation Spool Radiator Fan Valve Radiator Fan Reverse Rotation Control Solenoid Valve Oil Cooler Fan Reverse Rotation Spool Oil Cooler Fan Valve Oil Cooler Fan Reverse Rotation Control Solenoid Valve Pump 2 Regulator Pressure Sensor Pump 2 Control Solenoid Valve

27- Pump 2 Delivery Pressure Sensor 28- Pump 1 Regulator Pressure Sensor 29- Pump 1 Control Solenoid Valve 30- Pump 1 Delivery Pressure Sensor 31- Pump 3 Regulator Pressure Sensor 32- Pump 3 Control Solenoid Valve 33- Pump 3 Delivery Pressure Sensor 34- 4-Spool Solenoid Valve Unit 35- Main Control Valve 36- Main Relief Valve 37- Boom Overload Relief Selector Valve

T2-2-53

38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System 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 digging switch (43) is turned ON, MC1 (13) continuously activates the 4-spool solenoid valve unit (34) (SF). 2. When the 4-spool solenoid valve unit (34) (SF) is activated, the pilot pressure acts on main relief valve (36) and increases the relief pressure. (Refer to COMPONENT OPERATION/Control Valve.)

TOKAA90-EN-00

T2-2-54

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-55

TKAB-02-02-027 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System 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, MC1 (13) activates the 4-spool solenoid valve unit (34) (SF).  Pressure sensor (boom raise) (2): Outputting signal (The boom pilot pressure must be increased to the specified pressure.) (Reference: 0.7 MPa)  Pump 1 delivery pressure sensor (30): High (Reference: 29 MPa)  Pressure sensor (arm roll-in) (4): Specified pressure or lower (Reference: 0.7 MPa) 2. When the 4-spool solenoid valve unit (34) (SF) is activated, the pilot pressure acts on main relief valve (36) and increases the relief pressure. (Refer to COMPONENT OPERATION/Control Valve.)

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

TOKAA90-EN-00

T2-2-56

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-57

TKAB-02-02-028 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System Travel Motor Displacement Angle Control Purpose: The travel motor displacement angle control controls the travel mode. Operation:  Slow speed 1. When travel mode switch (44) is in slow speed position (45), the travel motor displacement angle is kept in the maximum angle, and the travel speed is slow.  Fast speed 1. When all following conditions exist, MC1 (13) activates the 4-spool solenoid valve unit (34) (SC).  Travel mode switch (44): Fast speed position (46)  Pressure sensor (travel) (9): Outputting signal  Pump 1, 2 delivery pressure sensors (30, 27): The delivery pressure of both pumps is low. (Reference: less than 20.1 MPa)  Pressure sensor (4-spool side) (10) or Pressure sensor (5-spool side) (11): The pilot pressure of either pump or both pumps is high. (Reference: over 3.0 MPa) 2. When the 4-spool solenoid valve unit (34) (SC) is activated, the pilot pressure acts on the travel motor displacement angle control valve (39) and decreases the displacement angle to the minimum so that the travel speed increases.

TOKAA90-EN-00

T2-2-58

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-59

TKAB-02-02-029 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System Pressure Rising Selection Control When Traveling Purpose: The pressure rising selection control when traveling increases the main relief valve pressure when performing travel operation. Operation: 1. MC1 (13) receives the signal from pressure sensor (travel) (9) when performing travel operation. MC1 (13) activates the 4-spool solenoid valve unit (34) (SF). 2. When the 4-spool solenoid valve unit (34) (SF) is activated, the pilot pressure acts on main relief valve (36) and increases the relief pressure. (Refer to COMPONENT OPERATION/Control Valve.)

TOKAA90-EN-00

T2-2-60

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-61

TKAB-02-02-026 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System Boom Mode Control Purpose: The boom mode control reduces body vibration by decreasing the relief pressure of the overload relief valve during digging and level operation. Operation: 1. When all following conditions exist, MC1 (13) activates the 4-spool solenoid valve unit (34) (SI).  Boom mode switch (42): ON  Pressure sensor (travel) (9): No outputting signal  Pressure sensor (boom raise (2), boom lower (3), arm roll-in (4), arm roll-out (5), bucket roll-in (6), bucket roll-out (7), auxiliary (12) (OP)): Either of pressure sensors: Outputting signal 2. Pressure oil from the pilot pump flows through the 4-spool solenoid valve unit (34) (SI) and acts on the boom overload relief selector valve (37). 3. When the boom overload relief selector valve (37) is shifted, the relief set pressure of the overload relief valve decreases. 4. As the holding pressure at the boom cylinder rod side decreases, body vibration during boom lower operation decreases. (Refer to COMPONENT OPERATION/Control Valve/ Boom Overload Relief Selector Valve.)

fNOTE: When output of either of pressure sensors (boom raise (2), boom lower (3), arm roll-in (4), arm roll-out (5), bucket roll-in (6), bucket roll-out (7), auxiliary (12) (OP)) exceeds 0.7 MPa, MC1 (13) recognizes that the control lever is operated.

TOKAA90-EN-00

T2-2-62

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-63

TKAB-02-02-030 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System Bypass Cut Valve Control During Boom Lowering Purpose: The bypass cut valve control during boom lowering can make the track be raised off the ground, and reduces hunting with the track raised off the ground. Operation: 1. When all following conditions exist, MC1 (13) activates the 4-spool solenoid valve unit (34) (SG).  Pressure Sensor (Boom Lower) (3): Outputting signal  Boom Bottom Pressure Sensor (51): less than 1 MPa 2. When the 4-spool solenoid valve unit (34) (SG) is activated, the bypass shut-out valve (4-spool side) (38) is shifted by the pilot pressure. 3. Pressure oil from pump 1 flows to boom 1 spool (54) through the boom 1 flow rate control valve (53). 4. Pressure oil from boom 1 spool (54) flows to the boom rod side. Therefore, the jack-up force increases.

TOKAA90-EN-00

T2-2-64

SECTION 2 SYSTEM Group 2 Control System 16

20 21 19

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

53 54

123456789101112131415-

TOKAA90-EN-00

161718192021222324-

252627-

Monitor ECM Engine Radiator Fan Reverse Rotation Spool Radiator Fan Valve Radiator Fan Reverse Rotation Control Solenoid Valve Oil Cooler Fan Reverse Rotation Spool Oil Cooler Fan Valve Oil Cooler Fan Reverse Rotation Control Solenoid Valve Pump 2 Regulator Pressure Sensor Pump 2 Control Solenoid Valve Pump 2 Delivery Pressure Sensor

28- Pump 1 Regulator Pressure Sensor 29- Pump 1 Control Solenoid Valve 30- Pump 1 Delivery Pressure Sensor 31- Pump 3 Regulator Pressure Sensor 32- Pump 3 Control Solenoid Valve 33- Pump 3 Delivery Pressure Sensor 34- 4-Spool Solenoid Valve Unit 35- Main Control Valve 36- Main Relief Valve 37- Boom Overload Relief Selector Valve 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve

4041424344454647484950515253-

T2-2-65

TKAB-02-02-032

2-Spool Solenoid Valve Unit Fan Reverse Rotation Switch Boom Mode Switch Power Digging Switch Travel Mode Switch Slow Speed Position Fast Speed Position Power Mode Switch Engine Control Dial Key Switch Pilot Shut-Off Switch Boom Bottom Pressure Sensor Arm 2 Flow Rate Control Valve Boom 1 Flow Rate Control Valve 54- Boom 1 Spool

SECTION 2 SYSTEM Group 2 Control System Arm 2 Flow Rate Control Purpose: The arm 2 flow rate control increases the boom raise speed during digging operation. The arm 2 flow rate control circuit enables the arm level crowding operation during arm level crowding operation.  When performing arm level crowding operation 1. When all following conditions exist, MC1 (13) activates the 2-spool solenoid valve unit (40) (SI).

Operation:  When performing digging operation 1. When all following conditions exist, MC1 (13) activates the 2-spool solenoid valve unit (40) (SI).

 Pressure Sensor (Boom Raise) (2): Outputting signal  Pressure Sensor (Arm Roll-In) (4): Outputting signal  Pump 1 Delivery Pressure Sensor (30), Pump 2 Delivery Pressure Sensor (27), Pump 3 Delivery Pressure Sensor (33): All delivery pressure of pumps is low. (Reference: less than 22 MPa)

 Pressure Sensor (Boom Raise) (2): Outputting signal  Pressure Sensor (Arm Roll-In) (4): Outputting signal  Pump 1 Delivery Pressure Sensor (30), Pump 2 Delivery Pressure Sensor (27), Pump 3 Delivery Pressure Sensor (33): The delivery pressure of pumps is high. (Reference: over 22 MPa)

2. The 2-spool solenoid valve unit (40) (SI) outputs lower pilot pressure. The pilot pressure acts on the arm 2 flow rate control valve (52).

2. The 2-spool solenoid valve unit (40) (SI) is activated. The output pilot pressure shifts the arm 2 flow rate control valve (52).

3. Therefore, pressure oil from pump 1 is restricted by the arm 2 flow rate control valve (52) so that the specified flow rate of pressure oil can flow to the arm 2 spool.

3. Pressure oil which flows from pump 1 to the arm 2 spool is restricted by the arm 2 flow rate control valve (52). 4. As the pressure oil flow rate which flows from pump 1 to the arm 2 spool is reduced, the pressure oil flow rate which flows from pump 1 to the boom 1 spool increases. Then, the boom raise speed increases.

4. Pressure oil from pump 1 flows to the boom 1 spool and arm 2 spool in good balance. This enables the arm level crowding operation.

fNOTE: When all delivery pressure sensors (30, 27, 33) of

pumps 1, 2, 3 are abnormal, the same control as the arm level crowding operation is performed.

fNOTE: The reduced amount of the arm 2 flow rate control valve (52) can be adjusted by MPDr. during arm level crowding operation. (Arm 2 Flw Cont P/S Correction)

TOKAA90-EN-00

T2-2-66

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-67

TKAB-02-02-049

SECTION 2 SYSTEM Group 2 Control System Fan Reverse Rotation Control Purpose: The fan reverse rotation control turns the oil cooler fan and radiator fan in reverse, and cleans the oil cooler and radiator. Operation: 1. When the fan reverse rotation switch is turned ON, MC1 (13) activates the oil cooler fan reverse rotation control solenoid valve (24) and radiator fan reverse rotation control solenoid valve (21). 2. When the oil cooler fan reverse rotation control solenoid valve (24) and radiator fan reverse rotation control solenoid valve (21) are activated, pressure oil from the pilot pump shifts the oil cooler fan reverse rotation spool (22) and radiator fan reverse rotation spool (19). 3. The delivery ports of the oil cooler fan valve (23) and radiator fan valve (20) are shifted. Then, the fan motors turns in reverse. (Refer to SYSTEM/Hydraulic System.) Therefore, accumulated dirt in the oil cooler and radiator cores is discharged.

TOKAA90-EN-00

T2-2-68

SECTION 2 SYSTEM Group 2 Control System 14

16 20 21 15

1 2 3 4 5 6 7 8 9 10 11 12 51 33

50 49 48 47

22 23 24

46 45 44 43

42 34

39 52 1234567891011121314-

TOKAA90-EN-00

15161718192021222324-

2526-

T2-2-69

TKAB-02-02-031 38- Bypass Shut-Out Valve (4-Spool Side) 39- Travel Motor Displacement Angle Control Valve 40- 2-Spool Solenoid Valve Unit 41- Fan Reverse Rotation Switch 42- Boom Mode Switch 43- Power Digging Switch 44- Travel Mode Switch 45- Slow Speed Position 46- Fast Speed Position 47- Power Mode Switch 48- Engine Control Dial 49- Key Switch 50- Pilot Shut-Off Switch 51- Boom Bottom Pressure Sensor 52- Arm 2 Flow Rate Control Valve

SECTION 2 SYSTEM Group 2 Control System Other Control The other control consists of the followings.  Work Mode Control  Auto Shut-Down Control  Auto-Lubrication Control (Quicklub Lubrication System)  * Auto-Lubrication Control (Centro Matic System)  Hydraulic Oil Overheat Alarm Control  * Swing Alarm Control  * Travel Alarm Control  * Overload Alarm Control NOTE: *: This control is for only the machine with the optional parts equipped.

TOKAA90-EN-00

T2-2-70

SECTION 2 SYSTEM Group 2 Control System Work Mode Control The work mode control consists of digging mode and attachment mode 1 to 11. The mode can be selected by the monitor.  Digging Mode: The normal control is performed.  Attachment Mode: This functions only machine with optional parts equipped. The upper limit of the maximum pump 2 flow rate is limited according to the kind of attachment. (Refer to T2-2-38 to 39.) The increasing/decreasing settings are made by MPDr.. NOTE: As the attachment mode, one to eleven attachment modes can be selected by MPDr..  Unset1 to 5  Breaker 1 to 5  Pulverizer 1 to 5  Crusher 1 to 5  Vibrating Hammer 1 to 5  Other 1 to 5  Grapple 1 to 5  Clamshell 1 to 5  Thumb 1 to 5  Tilting Rotator 1 to 5  Tilting Bucket 1 to 5

TOKAA90-EN-00

T2-2-71

SECTION 2 SYSTEM Group 2 Control System 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.

fNOTE: The auto shut-down ON/OFF can be selected

Operation: 1. When all following conditions exist, MC1 (2) sends the auto shut-down signal to monitor controller (5) by using CAN communication (3).

and reset it to the START position, and the engine can restart.

and the time when the auto shut-down control is activated can be set by monitor (6).

fNOTE: Return the key switch to the OFF or ACC position

 Pilot shut-off switch (15): OFF (Pilot shut-off lever: LOCK position)  Auto shut-down: ON  Overheat alarm: OFF  Coolant temperature: less than 100 °C  Abnormal communication of ECM (8) or monitor controller (5): None  Overload alarm switch (16) (option): OFF 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. MC1 (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.) 4. When the engine speed is decreased to the slow idle speed, MC1 (2) turns ON auto shut-down relay (13). 5. When auto shut-down relay (13) is ON, the battery relay is turned OFF and the engine stops. (Refer to SYSTEM/Electrical System.)

TOKAA90-EN-00

T2-2-72

SECTION 2 SYSTEM Group 2 Control System 4

6 5 15

7 3

11 10

TKAB-02-02-033

123-

Hydraulic Oil Temperature Sensor MC1 CAN

TOKAA90-EN-00

4567-

MPDr. Monitor Controller Monitor Buzzer

8- ECM 10- Coolant Temperature Sensor 11- Engine 13- Auto Shut-Down Relay

T2-2-73

14- Engine Control Dial 15- Pilot Shut-Off Switch 16- Overload Alarm Switch (Option)

SECTION 2 SYSTEM Group 2 Control System Auto-Lubrication Control (Quicklub Lubrication System)

13. When the number of times (number of reciprocating motion) reaches to the set value, MC1 (2) disconnects terminal #C17 from the ground.

Purpose: The auto-lubrication control (quicklub lubrication system) controls the auto-lubrication device so that auto-lubrication can be correctly performed. (Refer to COMPONENT OPERATION/Others (Upperstructure)/ Distribution Valve.)

14. As auto-lubrication relay 1 (8) and auto-lubrication relay 2 (13) are turned OFF, no current flows to grease pump (9) and grease pump (9) is stopped.

Operation: 1. When the lubrication mode selection switch (1) is set to the auto position, MC1 (2) connects terminal #C17 to the ground inside. 2. Therefore, auto-lubrication relay 1 (8) and autolubrication relay 2 (13) are excited. 3. Current from fuse #5 (7) flows to grease pump (9) and proximity switch (11). 4. Grease pump (9) is operated and auto-lubrication starts. 5. While auto-lubrication relay 1 (8) and autolubrication relay 2 (13) are ON, grease pump (9) is operated and grease is discharged.

15. When the set interval passed, MC1 (2) connects terminal #C17 to the ground again. Then, grease pump (9) is operated and auto-lubrication is resumed. 16. When the signal from proximity switch (11) is not sent to terminal #E3 in MC1 (2) within 5 minutes after auto-lubrication relay 1 (8) and autolubrication relay 2 (13) were turned ON, MC1 (2) recognizes that malfunction (such as no grease or faulty grease pump) of the auto-lubrication circuit has occurred. MC1 (2) sends the signal to monitor controller (5) by using CAN communication (3). 17. Monitor controller (5) displays the auto-lubrication alarm on monitor (6).

fNOTE: The lubrication time and interval can be set on

6. When grease is discharged from grease pump (9), the piston of distribution valve (10) moves.

monitor (6) or by using MPDr. (4).

7. Proximity switch (11) is installed in distribution valve (10) and is turned ON/OFF in response to the movement of the piston of distribution valve (10). 8. When the piston on distribution valve (10) comes close to proximity switch (11), proximity switch (11) is turned ON and transistor (12) in proximity switch (11) is turned ON. 9. Therefore, terminal #E3 in MC1 (2) is connected to the ground through proximity switch (11). 10. When the piston on distribution valve (10) gets away from proximity switch (11), proximity switch (11) is turned OFF and transistor (12) is turned OFF. 11. Therefore, the signal from terminal #2 in proximity switch (11) is input to terminal #E3 in MC1 (2). 12. MC1 (2) detects the number of distribution valve (10) operating times (number of reciprocating motion) according to the signal input to terminal #E3.

TOKAA90-EN-00

T2-2-74

SECTION 2 SYSTEM Group 2 Control System

14 7

6 1

8 C17

2 1

12 TKAB-02-02-046

123-

Lubrication Mode Selection Switch MC1 CAN

TOKAA90-EN-00

4567-

MPDr. Monitor Controller Monitor Fuse #5

891011-

T2-2-75

Auto-Lubrication Relay 1 Grease Pump Distribution Valve Proximity Switch

12- Transistor 13- Auto-Lubrication Relay 2 14- Current from Battery

SECTION 2 SYSTEM Group 2 Control System Auto-Lubrication Control (Centro Matic System) (Option)

7. When pressure switch (10) is turned ON, MC1 (2) disconnects terminal #C17 from the ground.

Purpose: The auto-lubrication control (centro matic system) controls the auto-lubrication device so that autolubrication can be correctly performed. (Refer to COMPONENT OPERATION/Others (Upperstructure)/ Distribution Valve.)

8. As auto-lubrication relay 1 (8) and auto-lubrication relay 2 (13) are turned OFF, no current flows to the motor of grease pump (9) and grease pump (9) is stopped.

Operation: 1. When the lubrication mode selection switch (1) is set to the auto position, MC1 (2) connects terminal #C17 to the ground inside. 2. Therefore, auto-lubrication relay 1 (8) and autolubrication relay 2 (13) are excited. 3. Current from fuse #5 (7) flows to the motor of grease pump (9) and the auto-lubrication solenoid valve (11). 4. Grease pump (9) is operated and auto-lubrication starts.

9. When the set interval passed, MC1 (2) connects terminal #C17 to the ground again. Then, grease pump (9) is operated and auto-lubrication is resumed. 10. When the signal from pressure switch (10) is not sent to terminal #E3 in MC1 (2) within 5 minutes after auto-lubrication relay 1 (8) and autolubrication relay 2 (13) were turned ON, MC1 (2) recognizes that malfunction (such as no grease or faulty grease pump) of the auto-lubrication circuit has occurred. MC1 (2) sends the signal to monitor controller (5) by using CAN communication (3). 11. Monitor controller (5) displays the auto-lubrication alarm on monitor (6).

5. While auto-lubrication relay 1 (8) and autolubrication relay 2 (13) are ON, grease pump (9) is operated and grease is discharged.

fNOTE: The lubrication time and interval can be set on

6. Pressure switch (10) is installed in the lubrication circuit. When the lubrication circuit pressure increases over the set pressure, pressure switch (10) is turned ON.

TOKAA90-EN-00

T2-2-76

monitor (6) or by using MPDr. (4).

SECTION 2 SYSTEM Group 2 Control System

14 7

6 1

8 C17

TKAB-02-02-042

123-

Lubrication Mode Selection Switch MC1 CAN

TOKAA90-EN-00

4567-

MPDr. Monitor Controller Monitor Fuse #5

8- Auto-Lubrication Relay 1 9- Grease Pump 10- Pressure Switch

T2-2-77

11- Auto-Lubrication Solenoid Valve 13- Auto-Lubrication Relay 2 14- Current from Battery

SECTION 2 SYSTEM Group 2 Control System Hydraulic Oil Overheat Alarm Control

fNOTE: The temperature, judging time, and buzzer

Purpose: When hydraulic oil temperature increases over the specified value, the hydraulic oil overheat alarm control sounds buzzer (7).

ON/OFF operation of the hydraulic oil overheat alarm control can be set by MPDr. (4).

Operation: 1. The signal from the hydraulic oil temperature sensor (1) is sent to MC1 (2). 2. When hydraulic oil temperature is kept high for a specified period of time, MC1 (2) sends the signal to monitor controller (5) by using CAN communication (3). 3. Monitor controller (5) sounds buzzer (7) and displays the hydraulic oil overheat alarm on monitor (6). 4. When hydraulic oil temperature decreases, monitor controller (5) stops buzzer (7) and deletes the hydraulic oil overheat alarm on monitor (6).

1 4

7 TDAA-02-02-010

Hydraulic Oil Temperature Sensor

TOKAA90-EN-00

23-

MC CAN

45-

T2-2-78

MPDr. Monitor Controller

67-

Monitor Buzzer

SECTION 2 SYSTEM Group 2 Control System Swing Alarm Control (Option) Purpose: The swing alarm control sounds buzzer (3) and turns on beacon light (4) when performing the swing operation. Operation: 1. MC1 (2) receives the signal from pressure sensor (swing) (1) when the swing operation is performed. 2. As long as MC1 (2) receives this signal, MC1 (2) sends the signal, sounds buzzer (3), and turns on beacon light (4).

4 TKAB-02-02-034

Pressure Sensor (Swing)

TOKAA90-EN-00

MC1

T2-2-79

Buzzer

Beacon Light

SECTION 2 SYSTEM Group 2 Control System Travel Alarm Control (Option) Purpose: The travel alarm control sounds buzzers (6, 7) when performing the travel operation. Operation: 1. MC1 (2) receives the signal from pressure sensor (travel) (1) when the travel operation is performed. 2. As long as MC1 (2) receives this signal, MC1 (2) sends the signal to travel alarm device (fender side) (3) and travel alarm device (rear side) (4), and sounds buzzers (6, 7).

fNOTE: After traveling continuously for over 13 seconds, buzzers (6, 7) can be deactivated by the travel alarm deactivation switch (5).

2 6 5

4 7 TKAB-02-02-043

12-

Pressure Sensor (Travel) MC1

34-

TOKAA90-EN-00

Travel Alarm Device (Fender Side) Travel Alarm Device (Rear Side)

56-

T2-2-80

Travel Alarm Deactivation Switch Buzzer

Buzzer

SECTION 2 SYSTEM Group 2 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.

fNOTE: The alarm pressure setting (Tipping Threshold Boom CYL Bottom Pressure) of load in MC1 (2) can be adjusted by MPDr. (5).

Operation: 1. When all following conditions exist, MC1 (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 2. As long as receiving the signal from MC1 (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).

4 7 2

6 D7

TKAB-02-02-044

12-

Overload Alarm Switch MC1

TOKAA90-EN-00

34-

Boom Bottom Pressure Sensor CAN

56-

T2-2-81

MPDr. Monitor Controller

78-

Monitor Buzzer

SECTION 2 SYSTEM Group 2 Control System (Blank)

TOKAA90-EN-00

T2-2-82

SECTION 2 SYSTEM Group 3 Engine System ECM System ECM receives the signals from sensors and MC1. ECM processes and performs the following controls.  Injector Control  Slow Idle Control at Low Temperature  Low Temperature Start Control (Option)  Troubleshooting Control

TOKAA90-EN-00

T2-3-1

SECTION 2 SYSTEM Group 3 Engine System Injector Control ECM (12) activates injector (13) and controls the engine by receiving the signal of target engine speed (Power CAN (11)) and the signals from control sensors such as engine speed sensor (1), the fuel pump delivery pressure sensor (2), the fuel timing pressure sensor (3), and fuel pressure sensor (4). Slow Idle Control at Low Temperature ECM (12) keeps the engine speed at slow idle speed until temperature of coolant temperature sensor (6), fuel temperature sensor (9), and the intake manifold temperature sensor (7) reaches the specified temperature. Low Temperature Start Control (Option) ECM (12) excites ether solenoid (18) and improves the engine starting ability when the detected temperature is lower than the specified temperature by the signal from the intake manifold temperature sensor (7). Troubleshooting Control ECM (12) controls the engine speed, fuel injection amount, and engine stop by receiving the signal of target engine speed (Power CAN (11)) and the erratic data from control sensors such as engine speed sensor (1), the fuel pump delivery pressure sensor (2), the fuel timing pressure sensor (3), fuel pressure sensor (4), fuel temperature sensor (9), engine oil pressure sensor (5), coolant temperature sensor (6), and the intake manifold temperature sensor (7). ECM (12) indicates trouble information by turning on and blinking engine fault code indicator lights (14, 15, 16). Then, ECM (12) sends the signal that the icon is displayed on the monitor.

TOKAA90-EN-00

T2-3-2

SECTION 2 SYSTEM Group 3 Engine System

13 1 2 3 14

4 5

TKAA90-02-03-001

12345-

Engine Speed Sensor Fuel Pump Delivery Pressure Sensor Fuel Timing Pressure Sensor Fuel Pressure Sensor Engine Oil Pressure Sensor

TOKAA90-EN-00

6789-

Coolant Temperature Sensor Intake Manifold Temperature Sensor Ambient Air Temperature Sensor (For Cummins) Fuel Temperature Sensor

1011121314-

T2-3-3

MC1 Power CAN ECM Injector Engine Maintenance Indicator Lamp

15- Engine Stop Indicator Lamp 16- Engine Warning Indicator Lamp 17- Monitor 18- Ether Solenoid

SECTION 2 SYSTEM Group 3 Engine System (Blank)

TOKAA90-EN-00

T2-3-4

SECTION 2 SYSTEM Group 4 Hydraulic System Outline The hydraulic system mainly consists of the pilot circuit, main circuit, transmission oil cooling circuit, and fan motor circuit. Pilot Circuit: Power Source Pilot Pump

Related Device

Supplied to

Pilot Valve

Operation Control Circuit

Pump Regulator

Pump Control Circuit

4-Spool Solenoid Valve Unit

Valve Control Circuit

2-Spool Solenoid Valve Unit

Travel Motor Displacement Angle Control Circuit

Signal Control Valve

Swing Parking Brake Release Circuit Hydraulic Oil Heat Circuit

Main Circuit: Power Source Main Pump

Related Device

Supplied to

Main Control Valve

Motor

Swing Control Valve

Cylinder

Transmission Oil Cooling Circuit: Power Source

Related Device

Supplied to

Transmission Oil Circulation Pump

Pump Transmission Oil Cooler

Pump Transmission

Fan Motor Circuit: Power Source Fan Pump

TOKAA90-EN-00

Related Device

Supplied to

Oil Cooler Fan Valve

Oil Cooler Fan Motor

Radiator Fan Valve

Radiator Fan Motor

T2-4-1

SECTION 2 SYSTEM Group 4 Hydraulic System Pilot Circuit Outline: Pressure oil from the pilot pump is used in order to operate the following circuits.  Operation Control Circuit  Pump Control Circuit  Valve Control Circuit  Travel Motor Displacement Angle Control Circuit  Swing Parking Brake Release Circuit  Hydraulic Oil Heat Circuit

fNOTE: Two accumulators are equipped for the pilot

circuit. The accumulators supply hydraulic oil to the pilot circuit for a period of time after the engine has been stopped.

TOKAA90-EN-00

T2-4-2

SECTION 2 SYSTEM Group 4 Hydraulic System

6 5 7 8

34 33

35 32

15 28

SC 22

26 27

25 TKAB-02-04-001

1234567-

Travel Pilot Valve Pilot Valve (Left) Pilot Valve (Right) Operation Control Circuit Boom Lower Shockless Valve Swing Control Valve Swing Parking Brake Release Circuit 8- Swing Motor 9- Pump 1 Regulator 10- Pump 2 Regulator

TOKAA90-EN-00

1112131415-

Pump 3 Regulator Fan Pump Regulator Pump Control Circuit Flow Combiner Valve Bypass Shut-Out Valve (5-Spool Side) 16- Arm 2 Flow Rate Control Valve 17- Bypass Shut-Out Valve (4-Spool Side) 18- Boom Overload Relief Selector Valve

192021222324252627-

Main Relief Valve Main Control Valve Hydraulic Oil Tank Suction Filter Pilot Pump Pilot Relief Valve Pilot Filter Travel Motor Travel Motor Displacement Angle Control Circuit 28- 4-Spool Solenoid Valve Unit

T2-4-3

29303132333435-

2-Spool Solenoid Valve Unit Valve Control Circuit Accumulator To Main Control Valve Spool Signal Control Valve Pilot Shut-Off Solenoid Valve Hydraulic Oil Heat Circuit

SECTION 2 SYSTEM Group 4 Hydraulic System Operation Control Circuit 1. The pilot valve controls pressure oil from pilot pump (B0) and moves the spools in main control valve (A8) and swing control valve (A9). 2. Signal control valve (B3) is provided between the pilot valve and main control valve (A8). Boom raise shockless valve (B4) is provided in the boom raise circuit in signal control valve (B3). 3. Boom raise shockless valve (B4) restricts returning oil from main control valve (A8) when stopping the boom raise operation and dampens the quick spool movement in main control valve (A8). (Refer to COMPONENT OPERATION/Signal Control Valve.) 4. Boom lower shockless valve (A6) is provided between the pilot valve (right) in the boom lower circuit and signal control valve (B3). 5. Boom lower shockless valve (A6) restricts returning oil from main control valve (A8) and swing control valve (A9) when stopping the boom lower operation, and dampens the quick spool movement in main control valve (A8) and swing control valve (A9). (Refer to COMPONENT OPERATION/Signal Control Valve.) 6. When the pilot shut-off solenoid valve (B2) is in the LOCK position, pressure oil does not flow to the pilot valve. Even if the control lever is operated, the machine is not operated. 7. Accumulators (B1) are equipped so that pressure oil can be supplied to the operation control circuit for a period of time after the engine has been stopped. Therefore, even when the engine is stopped with the front attachment raised due to troubles, pressure oil can be supplied to the spools in main control valve (A8) and swing control valve (A9) from accumulators (B1). Then, the front attachment can be operated.

TOKAA90-EN-00

T2-4-4

SECTION 2 SYSTEM Group 4 Hydraulic System A0

B2 B3 B4 B1

4 3 782 1 6 5 A7

B0 A9

12 9 10 18 17 16 15 14 13 A8

10 6

18 17

14 4

16 15

TKAA90-02-04-001 12345-

Boom Raise Boom Lower Arm Roll-In Arm Roll-Out Swing Left

A0- Travel (Left) A1- Travel (Right) A2- Swing A3- Arm A4- Boom

TOKAA90-EN-00

678910-

Swing Right Bucket Roll-In Bucket Roll-Out Travel (Left Forward) Travel (Left Reverse)

1112131415-

Travel (Right Forward) Travel (Right Reverse) Boom Raise Boom Lower Arm Roll-Out

A5- Bucket A6- Boom Lower Shockless Valve A7- To Swing Control Valve A8- Main Control Valve A9- Swing Control Valve

B0B1B2B3B4-

Pilot Pump Accumulator Pilot Shut-Off Solenoid Valve Signal Control Valve Boom Raise Shockless Valve

T2-4-5

16- Arm Roll-In 17- Bucket Roll-Out 18- Bucket Roll-In

SECTION 2 SYSTEM Group 4 Hydraulic System Pump Control Circuit (Refer to COMPONENT OPERATION/Pump Device.)  Main Pump Control by Pump Control Solenoid Valve 1. MC1 activates pump 1 control solenoid valve (9), pump 2 control solenoid valve (6), and pump 3 control solenoid valve (10) according to each actuator operation. (Refer to SYSTEM/Control System.) 2. Pilot pressure from pilot pump (4) is controlled by the pump 1 control solenoid valve (9), pump 2 control solenoid valve (6), and pump 3 control solenoid valve (10). The controlled pilot pressure is supplied to the regulators in pump 1 (2), pump 2 (5), and pump 3 (1) as the pump displacement angle control pressure. 3. 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 (4) is controlled by the fan pump control solenoid valve (8) and is supplied to the regulator in fan pump (3) as the fan pump control pressure. 2. The regulator increases or decreases the fan pump delivery flow rate according to the fan pump control pressure.

TOKAA90-EN-00

T2-4-6

SECTION 2 SYSTEM Group 4 Hydraulic System

8 10

TKAB-02-04-003

123-

Pump 3 Pump 1 Fan Pump

TOKAA90-EN-00

456-

Pilot Pump Pump 2 Pump 2 Control Solenoid Valve

89-

T2-4-7

Fan Pump Control Solenoid Valve Pump 1 Control Solenoid Valve

10- Pump 3 Control Solenoid Valve

SECTION 2 SYSTEM Group 4 Hydraulic System Valve Control Circuit (Refer to COMPONENT OPERATION/Control Valve, Travel Device.)  Pilot pressure from pilot pump (14) controls the following valves through the pilot valve, boom 1 spool (8), arm 1 spool (15), 4-spool solenoid valve unit (18) (SG, SI, SF, SC), 2-spool solenoid valve unit (19) (SC, SI), and flow combiner valve control spool (20) in signal control valve (3).  Boom 1 Spool (8): Boom 1 Anti-Drift Valve (9) and Boom 2 Anti-Drift Valve (17)  Arm 1 Spool (15): Arm 1 Anti-Drift Valve (16)  4-Spool Solenoid Valve Unit (18) (SG): Bypass ShutOut Valve (4-Spool Side) (12)  4-Spool Solenoid Valve Unit (18) (SI): Boom Overload Relief Selector Valve (10)  4-Spool Solenoid Valve Unit (18) (SF): Main Relief Valve (7) (increasing the set pressure)  4-Spool Solenoid Valve Unit (18) (SC): Travel Motor Displacement Angle Control Valve (13)  2-Spool Solenoid Valve Unit (19) (SC): Bypass ShutOut Valve (5-Spool Side) (5)  2-Spool Solenoid Valve Unit (19) (SI): Arm 2 Flow Rate Control Valve (11)  Flow Combiner Valve Control Spool (20) (Travel (Right) Pilot Pressure): Flow Combiner Valve (6) Travel Motor Displacement Angle Control Circuit (Refer to COMPONENT OPERATION/Travel Device.) Pilot pressure from the 4-spool solenoid valve unit (18) (SC) controls the travel motor displacement angle control valve (13).

TOKAA90-EN-00

T2-4-8

SECTION 2 SYSTEM Group 4 Hydraulic System 1

20 4

SC SI

17 a

SG SI SF

16 a 14

15 10 11

12 TKAA90-02-04-011

13 a-

Pilot Pressure from Boom 1 Spool (8)

12345-

Travel (Right Forward) Travel (Right Reverse) Signal Control Valve Main Control Valve Bypass Shut-Out Valve (5-Spool Side) Flow Combiner Valve

TOKAA90-EN-00

78910-

Main Relief Valve Boom 1 Spool Boom 1 Anti-Drift Valve Boom Overload Relief Selector Valve 11- Arm 2 Flow Rate Control Valve

12- Bypass Shut-Out Valve (4-Spool Side) 13- Travel Motor Displacement Angle Control Valve 14- Pilot Pump 15- Arm 1 Spool 16- Arm 1 Anti-Drift Valve

T2-4-9

17181920-

Boom 2 Anti-Drift Valve 5-Spool Solenoid Valve Unit 2-Spool Solenoid Valve Unit Flow Combiner Valve Control Spool

SECTION 2 SYSTEM Group 4 Hydraulic System Swing Parking Brake Release Circuit (Refer to COMPONENT OPERATION/Swing Device.) 1. When operating the front attachment or swing device, pilot pressure from the pilot valve is selected by shuttle valve (7) in signal control valve (6). And this pilot pressure shifts swing parking brake release spool (8). 2. Pilot pressure SH from pilot pump (10) is supplied to swing motor (9) and releases the swing parking brake. Hydraulic Oil Heat Circuit 1. When the pilot shut-off solenoid valve (11) is seated, pilot pressure oil is supplied to signal control valve (6). The hydraulic oil temperature increases due to orifice (5) in signal control valve (6). 2. This warmed pressure oil flows to signal control valve (6) and the pilot valves, and warms the pilot system components.

TOKAA90-EN-00

T2-4-10

SECTION 2 SYSTEM Group 4 Hydraulic System

TKAB-02-04-005

123-

Swing Arm Boom

TOKAA90-EN-00

456-

Bucket Orifice Signal Control Valve

78-

T2-4-11

Shuttle Valve Swing Parking Brake Release Spool

9- Swing Motor 10- Pilot Pump 11- Pilot Shut-Off Solenoid Valve

SECTION 2 SYSTEM Group 4 Hydraulic System Main Circuit Outline 1. The main pump (pump 1 (20), pump 2 (21), and pump 3 (19)) draws hydraulic oil from hydraulic oil tank (23) and delivers it to main control valve (8) and swing control valve (24). 2. Pressure oil from pump 1 (20) flows to travel (right) spool (14), bucket spool 1 (15), boom 1 spool (16), and arm 2 spool (17) through 4-spool side (A) in main control valve (8). 3. Pressure oil from pump 2 (21) flows to bucket 2 spool (13), arm 1 spool (12), boom 2 spool (11), auxiliary spool (10), and travel (left) spool (9) through 5-spool side (B) in main control valve (8). 4. Pressure oil from pump 3 (19) flows to boom 3 spool (25), swing spool (26), bucket 3 spool (27), and arm 3 spool (28) through in swing control valve (24). 5. Delivered hydraulic oil is supplied to the motors or cylinders in response to the spool operation of main control valve (8) and swing control valve (24). 6. Returning oil from the motors or cylinders returns to hydraulic oil tank (23) through main control valve (8) and oil cooler (3) or swing control valve (24). 7. When the oil temperature is low (high viscosity) and the oil flow resistance increases in oil cooler (3), bypass check valve (4) is opened and hydraulic oil directly returns to hydraulic oil tank (23).

TOKAA90-EN-00

T2-4-12

SECTION 2 SYSTEM Group 4 Hydraulic System

4 1

8 32 A

29 18

25 26

24 22

27 28

23 TKAB-02-04-007

A-

4-Spool Side

B-

5-Spool Side

12345678-

Radiator Fan Motor Oil Cooler Fan Motor Oil Cooler Bypass Check Valve Boom Cylinder Travel Motor (Right) Arm Cylinder Main Control Valve

910111213141516-

Travel (Left) Spool Auxiliary Spool Boom 2 Spool Arm 1 Spool Bucket 2 Spool Travel (Right) Spool Bucket 1 Spool Boom 1 Spool

TOKAA90-EN-00

1718192021222324-

T2-4-13

Arm 2 Spool Fan Pump Pump 3 Pump 1 Pump 2 Suction Filter Hydraulic Oil Tank Swing Control Valve

2526272829303132-

Boom 3 Spool Swing Spool Bucket 3 Spool Arm 3 Spool Swing Motor Bucket Cylinder Attachments Travel Motor (Left)

SECTION 2 SYSTEM Group 4 Hydraulic System Neutral Circuit 1. When the control lever is in neutral, pressure oil from the main pump (pump 1 (18), pump 2 (17), and pump 3 (19)) returns to hydraulic oil tank (27) through main control valve (1) and swing control valve (26). 2. Parallel circuits (5, 4, 24) are provided in each circuit of pump 1 (18), pump 2 (17), and pump 3 (19). The combined operation becomes possible. Flow Combiner Circuit 1. When performing boom raise, arm, and bucket rollin operation, pressure oil from three pumps (pump 1 (18), pump 2 (17), pump 3 (19)) is combined. 2. When performing bucket roll-out operation, pressure oil from pump 3 (19) is not combined, but pressure oil from pump 1 (18) and pump 2 (17) is combined. 3. When performing boom lower operation, pressure oil from pump 2 (17) and pump 3 (19) is not combined, but pressure oil from pump 1 (18) and the bottom side of boom cylinder (12) is combined. (Boom Lower Regenerative Circuit) Relief Circuit 1. Main relief valves (7, 40) are provided in the main circuit. 2. Main relief valves (7, 40) prevent the pressure in main circuit from exceeding the set pressure when the spool is operated (when the control lever is operated). 3. Overload relief valves (10, 14, 33, 35, 37, 41, 42) are provided in the actuator circuits (between the control valve and the actuators, and between swing control valve and the actuators) of boom, arm, bucket, and auxiliary. 4. Overload relief valves (10, 14, 33, 35, 37, 41, 42) prevent the pressure caused by external force in the actuator circuit from exceeding the set pressure. 5. Overload relief valves (10, 14, 33, 35, 37, 41, 42) have make-up function. When the pressure in the actuator circuit decreases, overload relief valves (10, 14, 33, 35, 37) draw pressure oil from hydraulic oil tank (27) and prevent cavitation from occurring. 6. Low-pressure relief valve (28) is provided in the return circuit of the main circuit. 7. Low-pressure relief valve (28) keeps the main circuit pressure constant and improves the actuator drawing performance when cavitation occurs. TOKAA90-EN-00

T2-4-14

SECTION 2 SYSTEM Group 4 Hydraulic System 1

9 10 37

36 35

34 33 32 31

14 16 15

40 20

24 25 26 41 27 1234567891011-

Main Control Valve Travel (Left) Spool Neutral Circuit (Pump 2) Parallel Circuit (Pump 2) Parallel Circuit (Pump 1) Travel (Right) Spool Main Relief Valve Travel Motor (Right) Bucket 1 Spool Overload Relief Valve Neutral Circuit (Pump 1)

TOKAA90-EN-00

1213141516171819202122-

Boom Cylinder Boom 1 Spool Overload Relief Valve Arm 2 Spool Arm Cylinder Pump 2 Pump 1 Pump 3 Boom 3 Spool Neutral Circuit (Pump 3) Swing Spool

2324252627282930313233-

T2-4-15

TKAA90-02-04-002 Bucket 3 Spool Parallel Circuit (Pump 3) Arm 3 Spool Swing Control Valve Hydraulic Oil Tank Low-Pressure Relief Valve Swing Motor Bucket 2 Spool Bucket Cylinder Arm 1 Spool Overload Relief Valve

343536373839404142-

Boom 2 Spool Overload Relief Valve Auxiliary Spool Overload Relief Valve Attachments Travel Motor (Left) Main Relief Valve Overload Relief Valve Overload Relief Valve

SECTION 2 SYSTEM Group 4 Hydraulic System Combined Operation Circuit  Swing, Boom Raise 1. When the boom is raised while swinging, pilot pressure shifts swing spool (9), boom 1 spool (2), boom 2 spool (13), and boom 3 spool (7). 2. Pressure oil from pump 1 (5) flows to boom cylinders (3) through parallel circuit (1) and boom 1 spool (2), and raises the boom. 3. Pressure oil from pump 2 (4) flows to boom cylinders (3) through parallel circuit (12) and boom 2 spool (13), and raises the boom. 4. Pressure oil from pump 3 (6) flows to swing motor (11) through parallel circuit (8) and swing spool (9), and swings the machine. At the same time, pressure oil from pump 3 (6) flows through parallel circuit (8) and boom 3 spool (7), is combined with pressure oil from pump 1 (5) and pump 2 (4), and flows to boom cylinders (3). Then, the boom is raised.

TOKAA90-EN-00

T2-4-16

SECTION 2 SYSTEM Group 4 Hydraulic System

13 2

7 8

1234-

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

TOKAA90-EN-00

5678-

Pump 1 Pump 3 Boom 3 Spool Parallel Circuit (Pump 3)

9101112-

T2-4-17

TKAA90-02-04-003

Swing Spool Hydraulic Oil Tank Swing Motor Parallel Circuit (Pump 2)

13- Boom 2 Spool

SECTION 2 SYSTEM Group 4 Hydraulic System Flow Combiner Circuit Purpose: The flow combiner circuit shifts flow combiner valve (4) when performing combined operation of travel and front attachment, and the machine can travel straight.  Travel, Boom Raise 1. When the boom is raised while traveling, pilot pressure shifts travel (right) spool (5), travel (left) spool (2), boom 1 spool (7), boom 2 spool (13), and boom 3 spool (12). 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 (3) from the pilot pump acts on flow combiner valve (4) through the signal control valve and shifts flow combiner valve (4). 3. Pressure oil from pump 1 (10) flows through travel (right) spool (5) and activates travel motor (right) (6). 4. At the same time, pressure oil from pump 1 (10) flows to travel (left) spool (2) through flow combiner valve (4) and activates travel motor (left) (1). 5. Pressure oil from pump 2 (9) flows to boom cylinder (8) through boom 2 spool (13) and raises the boom. 6. Pressure oil from pump 3 (11) flows through boom 3 spool (12), is combined with pressure oil from pump 2 (9), and raises the boom. 7. Pressure oil from pump 2 (9) and pressure oil from pump 3 (11) is used for the boom. Pressure oil from pump 1 (10) is equally supplied to both right and left travel motors and the machine can travel straight.

fNOTE: As the travel (right) circuit is a tandem circuit,

pressure oil from pump 1 (10) does not flow to boom 1 spool (7).

TOKAA90-EN-00

T2-4-18

SECTION 2 SYSTEM Group 4 Hydraulic System

6 2

8 7

12 11 10

TKAA90-02-04-004

123-

Travel Motor (Left) Travel (Left) Spool Primary Pilot Pressure from Pilot Pump (From Flow Combiner Valve Control Spool)

TOKAA90-EN-00

45678-

Flow Combiner Valve Travel (Right) Spool Travel Motor (Right) Boom 1 Spool Boom Cylinder

910111213-

T2-4-19

Pump 2 Pump 1 Pump 3 Boom 3 Spool Boom 2 Spool

SECTION 2 SYSTEM Group 4 Hydraulic System Arm 2 Flow Rate Control Circuit Purpose: The arm 2 flow rate control circuit increases the boom raise speed when performing combined operation of boom raise and arm roll-in. The arm 2 flow rate control circuit stabilizes the arm level crowding operation during arm level crowding operation.  When performing digging operation 1. When performing the combined operation of boom raise and arm roll-in, pilot pressure shifts boom 1 spool (2), boo 2 spool (18), boom 3 spool (14), arm 1 spool (17), arm 2 spool (8), and arm 3 spool (15). 2. At this time, MC1 activates the 2-spool solenoid valve unit (SI). (Refer to SYSTEM/Control System.)

8. Pressure oil from pump 1 (10) is restricted by the arm 2 flow rate control valve (poppet valve) (7) which is pushed by pressure oil from the arm 2 flow rate control valve (selector valve) (5). 9. Pressure oil from pump 1 (10) preferentially flows to boom cylinder (3) and the boom raise speed increases.

3. Pilot pressure (6) from the 2-spool solenoid valve unit (SI) shifts the arm 2 flow rate control valve (selector valve) (5). 4. Pressure oil from pump 2 (9) flows to boom cylinder (3) and arm cylinder (4) through parallel circuit (12), arm 1 spool (17), and boom 2 spool (18). Then, pressure oil raises the boom and roll in the arm. 5. Pressure oil from pump 3 (11) flows to boom cylinder (3) and arm cylinder (4) through boom 3 spool (14) and arm 3 spool (15). Then, pressure oil raises the boom and roll in the arm. 6. Pressure oil from pump 1 (10) flows to boom cylinder (3) through parallel circuit (1) and boom 1 spool (2). Then, pressure oil raises the boom.

TOKAA90-EN-00

7. At the same time, pressure oil from pump 1 (10) flows to the arm 2 flow rate control valve (poppet valve) (7) through parallel circuit (1).

T2-4-20

SECTION 2 SYSTEM Group 4 Hydraulic System

17 2

5 4

6 7

13 12 16

14 11

TKAA90-02-04-005

16 12345-

Parallel Circuit (Pump 1) Boom 1 Spool Boom Cylinder Arm Cylinder Arm 2 Flow Rate Control Valve (Selector Valve)

TOKAA90-EN-00

Pilot Pressure from 2-Spool Solenoid Valve Unit (SI) 7- Arm 2 Flow Rate Control Valve (Poppet Valve) 8- Arm 2 Spool 9- Pump 2 10- Pump 1

11121314151617-

T2-4-21

Pump 3 Parallel Circuit (Pump 2) Parallel Circuit (Pump 3) Boom 3 Spool Arm 3 Spool Hydraulic Oil Tank Arm 1 Spool

18- Boom 2 Spool

SECTION 2 SYSTEM Group 4 Hydraulic System  When performing arm level crowding operation 1. When performing the combined operation of boom raise and arm roll-in, pilot pressure shifts boom 1 spool (2), boo 2 spool (18), boom 3 spool (14), arm 1 spool (17), arm 2 spool (8), and arm 3 spool (15). 2. At this time, MC1 activates the 2-spool solenoid valve unit (SI). (Refer to SYSTEM/Control System.) 3. The 2-spool solenoid valve unit (SI) reduces pilot pressure. Reduced pilot pressure (6) is supplied to the arm 2 flow rate control valve (selector valve) (5). 4. The arm 2 flow rate control valve (selector valve) (5) balances the reduced pilot pressure with the spring force. 5. Pressure oil from pump 2 (9) flows to boom cylinder (3) and arm cylinder (4) through parallel circuit (12), arm 1 spool (17), and boom 2 spool (18). Then, pressure oil raises the boom and roll in the arm.

9. Pressure oil from pump 1 (10) is restricted to the specified amount by the arm 2 flow rate control valve (poppet valve) (7) which is pushed by pressure oil from the arm 2 flow rate control valve (selector valve) (5). 10. Therefore, pressure oil from pump 1 (10) appropriately flows to boom cylinder (3) and arm cylinder (4). This stabilizes the arm level crowding operation.

fNOTE: When all delivery pressure sensors of pump 1 (10), pump 2 (9), and pump 3 (11) are abnormal, the same control as the arm level crowding operation is performed.

fNOTE: The reduced amount of the arm 2 flow rate

6. Pressure oil from pump 3 (11) flows to boom cylinder (3) and arm cylinder (4) through boom 3 spool (14) and arm 3 spool (15). Then, pressure oil raises the boom and roll in the arm. 7. Pressure oil from pump 1 (10) flows to boom cylinder (3) through parallel circuit (1) and boom 1 spool (2). Then, pressure oil raises the boom. 8. At the same time, pressure oil from pump 1 (10) flows to the arm 2 flow rate control valve (poppet valve) (7) through parallel circuit (1).

TOKAA90-EN-00

T2-4-22

control valve can be adjusted by MPDr.. (Arm 2 Flow Rate Control P/S Adjustment)

SECTION 2 SYSTEM Group 4 Hydraulic System

17 2

5 4

6 7

13 12 16

14 11

TKAA90-02-04-006

12345-

Parallel Circuit (Pump 1) Boom 1 Spool Boom Cylinder Arm Cylinder Arm 2 Flow Rate Control Valve (Selector Valve)

TOKAA90-EN-00

Pilot Pressure from 2-Spool Solenoid Valve Unit (SI) 7- Arm 2 Flow Rate Control Valve (Poppet Valve) 8- Arm 2 Spool 9- Pump 2 10- Pump 1

11121314151617-

T2-4-23

Pump 3 Parallel Circuit (Pump 2) Parallel Circuit (Pump 3) Boom 3 Spool Arm 3 Spool Hydraulic Oil Tank Arm 1 Spool

18- Boom 2 Spool

SECTION 2 SYSTEM Group 4 Hydraulic System Arm Regenerative Cut Circuit Purpose: When the load is high at arm roll-in operation, the arm regenerative cut circuit flows back pressure oil at the arm cylinder (2) rod side to hydraulic oil tank (8) without regeneration for the bottom side. Therefore, pressure oil from pump 1 (4) is supplied to the arm and the digging force is improved.  Regeneration (Pump 1 (4) delivery pressure: Low) 1. Pressure oil from pump 1 (4) acts on the arm regeneration cut valve (6).

 Regeneration Cut (Pump 1 (4) delivery pressure: High) 1. When the load becomes heavy at arm roll-in operation, the arm regeneration cut valve (6) is shifted by pressure oil from pump 1 (4).

2. When the load is light at arm roll-in operation, the arm regeneration cut valve (6) is not shifted. 3. As returning oil from the cylinder rod side is restricted by the arm regeneration cut valve (6), 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 arm 1 spool (9) and flows to the cylinder bottom side. 5. The regeneration is done like this and the cylinder speed increases.

TOKAA90-EN-00

T2-4-24

2. Returning oil from the cylinder rod side flows to hydraulic oil tank (8) through arm 2 spool (1) and the arm regeneration cut valve (6). 3. The pressure at the arm cylinder (2) rod side decreases and the digging force is improved.

SECTION 2 SYSTEM Group 4 Hydraulic System

6 8 5

7 TKAA90-02-04-007

123-

Arm 2 Spool Arm Cylinder Pump 2

TOKAA90-EN-00

456-

Pump 1 Pump 3 Arm Regeneration Cut Valve

789-

T2-4-25

Arm 3 Spool Hydraulic Oil Tank Arm 1 Spool

SECTION 2 SYSTEM Group 4 Hydraulic System Bucket Regenerative Cut Circuit Purpose: When the load is high at bucket roll-in operation, the bucket regenerative cut circuit flows back pressure oil at the bucket cylinder (8) rod side to hydraulic oil tank (7) without regeneration for the bottom side. Therefore, the pressure at the bucket cylinder (8) 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.

 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).

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 1 spool (2) and flows to the cylinder bottom side. 5. The regeneration is done like this and the cylinder speed increases.

TOKAA90-EN-00

T2-4-26

2. Returning oil from the cylinder rod side flows to hydraulic oil tank (7) through bucket 1 spool (2) and the bucket regeneration cut valve (1). 3. The pressure at the bucket cylinder (8) rod side decreases and the digging force is improved.

SECTION 2 SYSTEM Group 4 Hydraulic System

1 2

7 5

TKAA90-02-04-008

123-

Bucket Regeneration Cut Valve Bucket 1 Spool Pump 2

TOKAA90-EN-00

456-

Pump 1 Pump 3 Bucket 3 Spool

789-

T2-4-27

Hydraulic Oil Tank Bucket Cylinder Bucket 2 Spool

SECTION 2 SYSTEM Group 4 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 restricts pressure oil which flows to boom cylinder (6) 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 force to raise the track increases.

fNOTE: As an example, the combined operation of boom lower and arm roll-out is explained here.

 Boom cylinder (6) 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 (16), arm 2 spool (9), arm 3 spool (14), boom 1 spool (8), boom 2 spool (17), and boom 3 spool (13). 2. When boom lower operation is done, the boom lower meter-in cut valve (4) is shifted by the boom cylinder (6) bottom pressure. 3. Boom lower pilot pressure (5) shifts the boom flow rate control valve (selector valve) (2) through the boom lower meter-in cut valve (4). 4. Pressure oil from pump 1 (11) acts on the boom flow rate control valve (poppet valve) (1) through parallel circuit (3) and the boom flow rate control valve (selector valve) (2). 5. As the back pressure of the boom flow rate control valve (poppet valve) (1) increases and the boom flow rate control valve (poppet valve) (1) is closed, pressure oil which flows from pump 1 (11) to boom 1 spool (8) is restricted by poppet valve (1). 6. Pressure oil in the boom cylinder (6) bottom side flows to the boom cylinder (6) rod side through boom 2 spool (17) due to boom own weight. 7. As pressure oil from pump 1 (11), pump 2 (10), and pump 3 (12) is used for the arm preferentially, arm roll-out speed increases.

TOKAA90-EN-00

T2-4-28

SECTION 2 SYSTEM Group 4 Hydraulic System

fNOTE: The illustration shows during combined operation of boom lower and arm roll-out. 1

13 15 12

15 TKAA90-02-04-009

123-

Boom Flow Rate Control Valve (Poppet Valve) Boom Flow Rate Control Valve (Selector Valve) Parallel Circuit (Pump 1)

TOKAA90-EN-00

4567-

Boom Lower Meter-In Cut Valve Boom Lower Pilot Pressure Boom Cylinder Arm Cylinder

89101112-

T2-4-29

Boom 1 Spool Arm 2 Spool Pump 2 Pump 1 Pump 3

1314151617-

Boom 3 Spool Arm 3 Spool Hydraulic Oil Tank Arm 1 Spool Boom 2 Spool

SECTION 2 SYSTEM Group 4 Hydraulic System  Boom cylinder (3) bottom pressure: Low (with the 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 the boom lower meter-in cut valve (2) is not shifted. 2. MC1 activates the 4-spool solenoid valve unit (SG) according to the boom cylinder (3) bottom pressure. (Refer to SYSTEM/Control System.) 3. Pressure oil from the pilot pump flows through the 4-spool solenoid valve unit (SG) and shifts the bypass shut-out valve (4-spool side) (9). 4. When the bypass shut-out valve (4-spool side) (9) is shifted, neutral circuit (1) of pump 1 (8) is blocked. 5. As the boom lower pilot pressure does not act on the boom flow rate control valve (selector valve) (4), the boom flow rate control valve (poppet valve) (5) is opened. 6. Pressure oil from pump 1 (8) flows to boom 1 spool (6). 7. Pressure oil in the boom cylinder (3) bottom side flows through boom 2 spool (12), is combined with pressure oil from boom 1 spool (6), and flows to the boom cylinder (3) rod side.

TOKAA90-EN-00

T2-4-30

SECTION 2 SYSTEM Group 4 Hydraulic System

1 2 12 3 4 5

11 10

11 TKAA90-02-04-010

1234-

Neutral Circuit (Pump 1) Boom Lower Meter-In Cut Valve Boom Cylinder Boom Flow Rate Control Valve (Selector Valve)

TOKAA90-EN-00

5678-

Boom Flow Rate Control Valve (Poppet Valve) Boom 1 Spool Pilot Pressure from 4-Spool Solenoid Valve Unit (SG) Pump 1

Bypass Shut-Out Valve (4-Spool Side) 10- Boom 3 Spool 11- Hydraulic Oil Tank 12- Boom 2 Spool

T2-4-31

SECTION 2 SYSTEM Group 4 Hydraulic System Transmission Oil Cooling Circuit 1. The transmission oil circulation pump (3) draws transmission oil from pump transmission (1) and supplies it to pump transmission oil cooler (6). 2. Transmission oil cooled by the pump transmission oil cooler (6) flows back to pump transmission (1). 3. When oil temperature is low (high viscosity) and oil flow resistance increases in the pump transmission oil cooler (6), check valve (4) is opened and transmission oil directly returns to pump transmission (1). 4. Therefore, transmission oil is prevented transmission oil temperature from rising, foreign matter is removed by the pump transmission oil filter (5), and the parts of pump transmission (1) are lubricated.

12-

Pump Transmission Manifold

TOKAA90-EN-00

Transmission Oil Circulation Pump

45-

T2-4-32

Check Valve Pump Transmission Oil Filter

TKAB-02-04-020

Pump Transmission Oil Cooler

SECTION 2 SYSTEM Group 4 Hydraulic System Fan Motor Circuit 1. Pressure oil from fan pump (6) flows to the oil cooler fan motor (1) and radiator fan motor (2) through ports M1 of the oil cooler fan valve (9) and radiator fan valve (4). 2. Hydraulic oil turns the oil cooler fan motor (1) and radiator fan motor (2), is combined with pressure oil returning from the main control, and returns to hydraulic oil tank (7).

3 4

12-

Oil Cooler Fan Motor Radiator Fan Motor

34-

TOKAA90-EN-00

Radiator Fan Reverse Rotation Spool Radiator Fan Valve

567-

T2-4-33

Pilot Pump Fan Pump Hydraulic Oil Tank

TKAB-02-04-017

89-

Oil Cooler Fan Reverse Rotation Spool Oil Cooler Fan Valve

SECTION 2 SYSTEM Group 4 Hydraulic System Fan Reverse Rotation Control Circuit Purpose: The fan reverse rotation control circuit turns the radiator fan and oil cooler fan in reverse, removes dirt and dust on the radiator and oil cooler, and recovers the cooling performance. 1. MC1 activates the radiator fan reverse rotation control solenoid valve (9) and oil cooler fan reverse rotation control solenoid valve (4) according to the signal from the fan reverse rotation switch. (Refer to SYSTEM/Control System.) 2. Pressure oil from pilot pump (6) flows through the radiator fan reverse rotation control solenoid valve (9) and oil cooler fan reverse rotation control solenoid valve (4), and shifts the radiator fan reverse rotation spool (10) and oil cooler fan reverse rotation spool (3). 3. Pressure oil from fan pump (7) flows to radiator fan motor (1) and the oil cooler fan motor (2) through ports M2 of radiator fan valve (11) and the oil cooler fan valve (5). Then, radiator fan motor (1) and the oil cooler fan motor (2) turn in reverse.

TOKAA90-EN-00

T2-4-34

SECTION 2 SYSTEM Group 4 Hydraulic System

3 4

9 8 7

123-

Radiator Fan Motor Oil Cooler Fan Motor Oil Cooler Fan Reverse Rotation Spool

TOKAA90-EN-00

56-

Oil Cooler Fan Reverse Rotation Control Solenoid Valve Oil Cooler Fan Valve Pilot Pump

789-

T2-4-35

Fan Pump Hydraulic Oil Tank Radiator Fan Reverse Rotation Control Solenoid Valve

TKAB-02-04-015

10- Radiator Fan Reverse Rotation Spool 11- Radiator Fan Valve

SECTION 2 SYSTEM Group 4 Hydraulic System (Blank)

TOKAA90-EN-00

T2-4-36

SECTION 2 SYSTEM Group 5 Electrical System Outline 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, the washer, and the sliding fold-in ladder alarm. The accessory circuit consists of MC2, the relays, and switches.  The control circuit controls the engine, pump, and valve. The control circuit consists of the actuators such as solenoid valves, MC1, ECM, sensors, and switches. (Refer to SYSTEM/Control System.)

TOKAA90-EN-00

T2-5-1

SECTION 2 SYSTEM Group 5 Electrical System Main Circuit The major functions and circuits in the main circuit are as follows.  The electric power circuit supplies all electric power to all electrical systems on the machine. {Key Switch, Battery, Fuses (Fuse Box, Slow Blow Fuse)}  The CAN circuit performs communication between each controller.  The starting circuit starts the engine. (Key Switch, Starter 1, Starter 2, Engine Protection Relay 1, Engine Protection Relay 2)  The charging circuit supplies electric power to the batteries and charges them. {Alternator, (Regulator)}  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 automatically stops the engine when the specified conditions exist. (MC1, Auto Shut-Down Relay, ACC Cut Relay, Key Switch ON Cut Relay)  The engine stop circuit (key switch: OFF) stops the engine by using ECM. (ECM)  The surge voltage prevention circuit prevents the occurrence of serge voltage developed when stopping the engine. (Load Dump Relay)

TOKAA90-EN-00

T2-5-2

SECTION 2 SYSTEM Group 5 Electrical System (Blank)

TOKAA90-EN-00

T2-5-3

SECTION 2 SYSTEM Group 5 Electrical System 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 (8) is in the OFF position. Battery (1)

Slow Blow Fuse 1 (5)

Fuse 1 (25)

TOKAA90-EN-00

Key Switch (8) Terminal B Load Dump Relay (6) Fuse Box 2 (23) Terminal Horn Relay (Power) (22) #24 Terminal MC1 (Power) (21) #26 Terminal Step Light Relay (Power) (20) #29 Terminal MC2 (Power) (19) #30 Terminal DLU (Power) (18) #31 Terminal Monitor Controller (Backup Power) (11) #35 GSM (Power) (12) Switch Panel (13) Cab Light (14) Security Horn (Power) (15) Security Horn Relay (Power) (16) Radio (Backup Power) (17) Terminal ACC ON Relay 2 (Power) (10) #39 Terminal ACC ON Relay 1 (Power) (9) #40 Fuse Box 3 (7) (Option) ECM (Power) (4)

T2-5-4

SECTION 2 SYSTEM Group 5 Electrical System

7 8

5 9 6

31 35 39 40

11 12 13 14 15 16 17

26 29 30

20 19 TKAA90-02-05-001

1456789-

Battery ECM (Power) Slow Blow Fuse 1 Load Dump Relay Fuse Box 3 (OP) Key Switch ACC ON Relay 1 (Power)

TOKAA90-EN-00

10- ACC ON Relay 2 (Power) 11- Monitor Controller (Backup Power) 12- GSM (Power) 13- Switch Panel 14- Cab Light 15- Security Horn (Power)

16171819202122-

T2-5-5

Security Horn Relay (Power) Radio (Backup Power) DLU (Power) MC2 (Power) Step Light Relay (Power) MC1 (Power) Horn Relay (Power)

23- Fuse Box 2 25- Fuse 1

SECTION 2 SYSTEM Group 5 Electrical System Electric Power Circuit (Key Switch: ACC) 1. When key switch (3) is set to the ACC position, terminal B is connected to terminal ACC (4) in key switch (3). 2. The circuits from the battery (1) positive terminal and terminal ACC (4) in key switch (3) are connected as shown below and makes each accessory operation possible. Battery (1)

Slow Blow Fuse 1 (2)

Fuse Box 2 (6)

Terminal #39 Terminal #40 Terminal #23 Terminal #36

Key Switch ACC Cut Relay (5) Terminal ACC (4) ACC ON Relay 1 (10) ACC ON Relay 2 (9)

fNOTE: When key switch (3) is set to the ON position, the operation of the lights, the wiper, the washer, and the sliding fold-in ladder alarm becomes possible.

TOKAA90-EN-00

T2-5-6

ACC ON Relay 2 (9) Option (8) ACC ON Relay 1 (10) Cigar Lighter (7) Radio (12) Monitor Controller (Power) (11)

SECTION 2 SYSTEM Group 5 Electrical System 4 3 5

36 39 40

TKAA90-02-05-002

123-

Battery Slow Blow Fuse 1 Key Switch

TOKAA90-EN-00

456-

Terminal ACC ACC Cut Relay Fuse Box 2

789-

T2-5-7

Cigar Lighter Option ACC ON Relay 2

10- ACC ON Relay 1 11- Monitor Controller (Power) 12- Radio

SECTION 2 SYSTEM Group 5 Electrical System Electric Power Circuit (Key Switch: ON) 1. When key switch (5) is in the ON position (or the engine is running), terminal B is connected to terminals ACC (6) and M (7) in key switch (5).

fNOTE: The alternator supplies power when the engine is running.

2. The circuit from the battery (1) positive terminal and terminal M (7) in key switch (5) are connected as shown below. Battery (1)

Battery Relay (11)

Slow Blow Fuse 3 (2)

Fuse Box 1 (4)

Slow Blow Fuse 2 (16)

Fuse Box 2 (9) Key Switch Terminal M (7) Slow Blow Key Switch Terminal M (7) Fuse 1 (3)

TOKAA90-EN-00

Fuse Box 2 (9) Key Switch ON Cut Relay (8)

T2-5-8

Fuse Box 2 (9)

#1 #2 #3 #4 #5 #6 #7 #8 #9 #10 #11 #14 #15 #16 #17 #18 #19 #20 #37 #38 #21 #25 #27 #28 #32 #34

Refer to T2-510.

Refer to T2-512.

SECTION 2 SYSTEM Group 5 Electrical System

4 2

3 9

1 16

10 TKAA90-02-05-003

A-

Refer to T2-5-11.

B-

Refer to T2-5-13.

123-

Battery Slow Blow Fuse 3 Slow Blow Fuse 1

456-

Fuse Box 1 Key Switch Terminal ACC

TOKAA90-EN-00

789-

T2-5-9

Terminal M Key Switch ON Cut Relay Fuse Box 2

10- Battery Relay 2 11- Battery Relay 1 16- Slow Blow Fuse 2

SECTION 2 SYSTEM Group 5 Electrical System Fuse Box 1 (1)

#2 #3 #4 #5

Pilot Shut-Off Relay (Power) Pilot Shut-Off Solenoid Valve Sliding Fold-In Ladder Relay (Power) Security Relay (Power) Alternator Signal Relay MC1 (Solenoid Valve Power) 12V Power Unit Air Conditioner Unit Work Light Relay 3 Auto-Lubrication Relay 1

Auto-Lubrication Relay 2 Work Light Relay 2

Work Light Relay 1

#8 #9

Back Light Relay Washer Relay Wiper Relay High 1 Wiper Relay Low (Power) Fuel Level Switch Pump Transmission Oil Level Switch Seat Heater (Option) Seat Compressor (Option) Travel Alarm Device (Fender Side) (Option) Travel Alarm Device (Rear Side) (Option) Beacon Light (Option)

#16 #17 #18 #19 #20

TOKAA90-EN-00

T2-5-10

Work Light (Cab Upper) Auto-Lubrication Relay 2 (Power) Proximity Switch Grease Pump Work Light Relay 3 (Power) Boom Light Back Light Relay (Power) Work Light (Right) Work Light (Left) Rear Light Washer Motor

SECTION 2 SYSTEM Group 5 Electrical System

TKAB-02-05-004

A-

Refer to T2-5-9.

Fuse Box 1

TOKAA90-EN-00

B-

From Slow Blow Fuse 3

C-

T2-5-11

From Slow Blow Fuse 2

SECTION 2 SYSTEM Group 5 Electrical System Fuse Box 2 (2)

#37 #38 #21

#25

#27 #28 #32

#34

TOKAA90-EN-00

Auxiliary 3 (Option) Auxiliary 1 (Option) Starter Cut Relay (Power) Auto Shut-Down Relay (Power) ACC Cut Relay (Power) Key Switch ON Cut Relay (Power) Buzzer Air Conditioner Unit GSM MC1 Engine Stop Switch 1 Battery Relay 1 Battery Relay 2 Load Dump Relay Monitor Controller Alternator (Terminal L) DLU MC2

T2-5-12

SECTION 2 SYSTEM Group 5 Electrical System

TKAA90-02-05-005

A-

Refer to T2-5-9.

Fuse Box 2

TOKAA90-EN-00

B-

From Key Switch Terminal M

C-

T2-5-13

From Key Switch ON Cut Relay

D-

From Slow Blow Fuse 2

SECTION 2 SYSTEM Group 5 Electrical System CAN Circuit CAN (Controller Area Network) is ISO Standards of the serial communication protocol. Four networks (CAN bus (3)) in the following are equipped for this machine.  Power CAN (4) is mainly used for the engine control.  Body CAN (5) is mainly used for the accessory control.  Monitoring CAN (7) is mainly used for display and log data communication.  DLU-CAN (8) is used for communication between DLU (17) and WIU (15) (option). CAN bus (3) consists of two wire harnesses, CAN-H (High) (1) and CAN-L (Low) (2). Each controller judges the CAN bus (3) level due to the potential difference between CAN-H (High) (1) and CAN-L (Low) (2). Each controller arranges the CAN bus (3) level and sends the signal and data to other controllers. Termination resistors (120 Ω) (14) are installed to both ends of CAN bus (3).

2 TKEB-02-05-017

12-

CAN-H (High) CAN-L (Low)

CAN Bus

9 14

12 11

5 13

21 14 14

15 20

16 TKAA90-02-01-001

45789-

Power CAN Body CAN Monitoring CAN DLU CAN MPDr.

TOKAA90-EN-00

1011121314-

Monitor Controller Monitor Monitor Control Unit Information Control Unit Termination Resistor (120 Ω)

1516171819-

T2-5-14

WIU (OP) CSU (OP) DLU Radio Controller Air Conditioner Controller

20- MC2 21- MC1 22- ECM

SECTION 2 SYSTEM Group 5 Electrical System (Blank)

TOKAA90-EN-00

T2-5-15

SECTION 2 SYSTEM Group 5 Electrical System Starting Circuit (Key Switch: START) 1. When key switch (6) is set to START position (5), terminal B is connected to terminals M (7) and ST (8) in key switch (6). 2. Current from terminal M (7) flows through the key switch ON cut relay (9) and fuse #32 and excites battery relay 1 (2) and battery relay 2 (3). Current from batteries (1) flows to terminals B in starter 1 (17) and starter 2 (16). 3. Current from terminal ST (8) flows to terminals C in starter 1 (17) and starter 2 (16) through starter cut relay (4), Engine Protection relay 1 (18), and Engine Protection relay 2 (19). 4. The coils of starter 1 (17) and starter 2 (16) are excited and the main contactor is attracted. For starter 1 (17) and starter 2 (16), terminals B are connected to terminals M. At the same time, the pinion gears are projected and meshed with the ring gear of the engine. 5. As terminals B are connected to terminals M of starter 1 (17) and starter 2 (16), current from battery relay 1 (2) and battery relay 2 (3) flows to each starter motor through terminals B of starter 1 (17) and starter 2 (16). Then, each starter motor turns. 6. And, current from terminal M (7) in key switch (6) flows to fuses #25, #27, #28, and #34 through the key switch ON cut relay (9). 7. Current from fuses #25, #27, #28, and #34 flows to GSM (13), MC1 (14), ECM (15), Monitor Controller (10), MC2 (11), DLU (12), and Alternator (20) as a signal indicating that key switch (6) is in the START position (5).

TOKAA90-EN-00

T2-5-16

SECTION 2 SYSTEM Group 5 Electrical System

7 8 6 9 5

M C

34 32 28

18 19 17

16 12

11 TKAA90-02-05-006

12345-

Battery Battery Relay 1 Battery Relay 2 Starter Cut Relay START Position

TOKAA90-EN-00

678910-

Key Switch Terminal M Terminal ST Key Switch ON Cut Relay Monitor Controller

1112131415-

T2-5-17

MC2 DLU GSM MC1 ECM

1617181920-

Starter 2 Starter 1 Engine Protection Relay 1 Engine Protection Relay 2 Alternator

SECTION 2 SYSTEM Group 5 Electrical System Charging Circuit (Key Switch: ON) 1. After the engine starts and key switch (4) is released, key switch (4) is returned to ON position (3). 2. Terminal B is connected to terminals ACC (5) and M (6) in key switch (4) with key switch (4) set in the ON position (3). 3. While current flows to terminal L in alternator (8), alternator (8) starts generating electricity with the engine running. Current from terminal B in alternator (8) flows to batteries (1) through battery relay 1 (2) and charges batteries (1). 4. Current from terminal AC in alternator (8) excites alternator relay (10). 5. Current from terminal B in alternator (8) flows through battery relay 1 (2), slow blow fuse 3 (9), and fuse #1, excites alternator signal relay (11), and flows to monitor controller (7). 6. Monitor controller (7) detects the alternator (8) generating electricity by the current from alternator (8) and deletes the alternator alarm on the monitor.

TOKAA90-EN-00

T2-5-18

SECTION 2 SYSTEM Group 5 Electrical System

5 6 4 3 10 9

2 11

1 AC

8 B

TKAA90-02-05-007

123-

Battery Battery Relay 1 ON Position

TOKAA90-EN-00

456-

Key Switch Terminal ACC Terminal M

789-

T2-5-19

Monitor Controller Alternator Slow Blow Fuse 3

10- Alternator Relay 11- Alternator Signal Relay

SECTION 2 SYSTEM Group 5 Electrical System Pilot Shut-Off Circuit (Key Switch: ON) 1. When the pilot shut-off lever is set to the UNLOCK position, pilot shut-off switch (13) is turned ON. 2. Current from fuse #1 flows to the ground through pilot shut-off relay (3) and pilot shut-off switch (13) and pilot shut-off relay (3) is excited. 3. When pilot shut-off relay (3) is excited, the ground circuit in the pilot shut-off solenoid valve (4) is connected to the ground through pilot shut-off relay (3), the sliding fold-in ladder relay (5), and security relay (6). 4. Therefore, the pilot shut-off solenoid valve (4) is turned ON and pressure oil from the pilot pump is supplied to the pilot valve.

fNOTE: When the pilot shut-off lever is set to the

UNLOCK position, terminal #B10 in monitor controller (11) is connected to the ground. Therefore, monitor controller (11) recognizes that the pilot shut-off lever is in the UNLOCK position and displays the image of the rear view camera on the monitor.

 Neutral Engine Start Circuit 1. When the pilot shut-off lever is set to the UNLOCK position, the coil of starter cut relay (7) is connected to the ground. 2. Therefore, starter cut relay (7) is excited. 3. Starter cut relay (7) disconnects, the circuits between terminal ST (9) in key switch (8) and terminals C of starter 1 (15) and starter 2 (14). 4. Therefore, when the pilot shut-off lever is in the UNLOCK position, even if key switch (8) is set to the START position, the starter does not rotate and the engine does not start.

fNOTE: When the pilot shut-off lever is set to the

UNLOCK position, terminal #F13 of MC1 (12) is connected to the ground. Therefore, MC1 (12) recognizes that the pilot shut-off lever is in the UNLOCK position.

TOKAA90-EN-00

T2-5-20

SECTION 2 SYSTEM Group 5 Electrical System

9 8

6 7

F13

2345-

B10 12

TOKAA90-EN-00

TKAA90-02-05-008

Battery Pilot Shut-Off Relay Pilot Shut-Off Solenoid Valve Sliding Fold-In Ladder Relay

6789-

Security Relay Starter Cut Relay Key Switch Terminal ST

10- Fuse Box 2 11- Monitor Controller 12- MC1

T2-5-21

13- Pilot Shut-Off Switch (Pilot Shut-Off Lever) 14- Starter 2 15- Starter 1

SECTION 2 SYSTEM Group 5 Electrical System Auto Shut-Down Circuit

fNOTE: When restarting the engine, return the key

switch to the OFF or ACC position and then reset it to the START position.

1. Current from terminal M (6) excites battery relay 1 (2) and battery relay 2 (3) through the key switch ON cut relay (9) with key switch (5) set in the ON position. 2. The circuits from terminal M (6) are connected to the coils of auto shut-down relay (7), ACC cut relay (8), the key switch ON cut relay (9), and starter cut relay (4) through fuse #21. 3. When all following conditions exist, MC1 (11) connects terminal #C5 to the ground inside. (Refer to SYSTEM/Control System.) Condition for Auto Shut-Down:  Pilot shut-off lever: LOCK position  Auto shut-down switch: ON  Overheat alarm: OFF  Coolant temperature: 60 to 100 °C  Abnormal communication of ECM and monitor controller: Void 4. Therefore, auto shut-down relay (7) is turned ON. ACC cut relay (8) and the key switch ON cut relay (9) are also turned ON at the same time. 5. The current which indicates key switch (5) is in the ON position, stops flowing from fuse #28 to the 31 pin connector terminal 1 of ECM (12). 6. At the same time, battery relay 1 (2) and battery relay 2 (3) are turned OFF. 7. Therefore, this is the same situation when key switch (5) is set to the OFF position. ECM (12) stops the fuel injection of the injector and stops the engine.

TOKAA90-EN-00

T2-5-22

SECTION 2 SYSTEM Group 5 Electrical System 6 5 7

28 32 10

C5 12

EC311 a

TKAA90-02-05-009

31 pin Connector Terminal 1

1234-

Battery Battery Relay 1 Battery Relay 2 Starter Cut Relay

TOKAA90-EN-00

5678-

Key Switch Terminal M Auto Shut-Down Relay ACC Cut Relay

9101112-

T2-5-23

Key Switch ON Cut Relay Fuse Box 2 MC1 ECM

SECTION 2 SYSTEM Group 5 Electrical System Engine Stop Circuit

1. When key switch (1) is set from the ON position to OFF position, current from terminal M (3) in key switch (1) stops flowing to the 31 pin connector terminal 1 (a) of ECM (8). 2. ECM (8) stops the fuel injection of the injector and stops the engine. 3. When the engine stops, ECM (8) is turned OFF. Engine Stopping by using Engine Stop Switches 1 and 2 When safety for the persons during inspection must be secured or when the engine does not stop due to some troubles that the machine is failed or damaged with key switch (1) set in the OFF position, push engine stop switch 1 (5) or engine stop switch 2 (6). Engine stop indicator (7) is turned on and the engine stops. After that, turn engine stop switch 1 (5) or engine stop switch 2 (6) clockwise and return it to the original position. Check that engine stop indicator (7) is turned off.

TKAB-02-05-010

1. If the engine does not stop after key switch (1) is set to the OFF position, terminal B (2) continues to be connected to terminal M (3) in key switch (1). 2. At this time, push engine stop switch 1 (5) or engine stop switch 2 (6). Then, the circuit between fuse #28 and the 31 pin connector terminal 1 (a) is disconnected.

TKAB-02-05-011

3. ECM (8) stops the fuel injection of the injector and stops the engine.

fNOTE: Even if the starter rotates with engine stop

switch 1 (5) or engine stop switch 2 (6) set in the ON position, the engine does not start.

TOKAA90-EN-00

Do not use engine stop switch 1 (5) dCAUTION: and engine stop switch 2 (6) unless absolutely

necessary. When the machine stops due to the machine failure, do not start the machine until the repair is completed.

T2-5-24

SECTION 2 SYSTEM Group 5 Electrical System 2 3 1

4 28

7 5

EC311 a

TKAA90-02-05-012 a-

31 pin Connector Terminal 1

12-

Key Switch Terminal B

TOKAA90-EN-00

34-

Terminal M Fuse Box 2

56-

T2-5-25

Engine Stop Switch 1 Engine Stop Switch 2

78-

Engine Stop Indicator ECM

SECTION 2 SYSTEM Group 5 Electrical System Surge Voltage Prevention Circuit 1. When the engine is stopped (key switch (5): OFF), current from terminal M in key switch (5) disappears and battery relay 1 (2) and battery relay 2 (3) are turned OFF. 2. The engine continues to rotate due to the inertia force just after key switch (5) is turned OFF and alternator (7) 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 (7) is generating electricity, the generating current from terminal AC in alternator (7) excites alternator relay (8). Current from terminal B in alternator (7) excites alternator signal relay (9) and flows to terminal #A15 in monitor controller (6). Monitor controller (6) connects terminal #D8 to the ground. 5. Therefore, current flows to the exciting circuit in load dump relay (4) and load dump relay (4) is turned ON. 6. Consequently, even if key switch (5) is set to the OFF position with the engine running, current from battery (1) continues to excite battery relay 1 (2) and battery relay 2 (3) through load dump relay (4). 7. In addition, when a specified time has passed since alternator (7) stops generating electricity, monitor controller (6) disconnects terminal #D8 from the ground. Therefore, battery relay 1 (2) and battery relay 2 (3) are turned OFF.

TOKAA90-EN-00

T2-5-26

SECTION 2 SYSTEM Group 5 Electrical System

8 4

3 2 9

1 AC 7 B D8

A15 6

TKAA90-02-05-013

123-

Battery Battery Relay 1 Battery Relay 2

TOKAA90-EN-00

456-

Load Dump Relay Key Switch Monitor Controller

789-

T2-5-27

Alternator Alternator Relay Alternator Signal Relay

SECTION 2 SYSTEM Group 5 Electrical System (Blank)

TOKAA90-EN-00

T2-5-28

SECTION 2 SYSTEM Group 5 Electrical System Monitor Circuit 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 Relay, Security Horn Relay)  The radio circuit operates the radio. (Monitor Controller, Switch Panel, Radio)  The air conditioner circuit operates the air conditioner. (Monitor Controller, Switch Panel, Air Conditioner Unit)

TOKAA90-EN-00

T2-5-29

SECTION 2 SYSTEM Group 5 Electrical System Security Circuit 1. When any one of the following condition exists, monitor controller (11) connects terminals #D15 and #D16 to the ground inside.  External alarm signal from e-Service: Exist  Numerical keypad password input error signal: Exist 2. Therefore, security horn relay (10), security relay (3), and starter cut relay (4) are excited. 3. When security horn relay (10) is excited, current from fuse #35 activates security horn (9). 4. When security relay (3) is excited, the ground circuit in the pilot shut-off solenoid valve (2) is disconnected and the pilot shut-off solenoid valve (2) is turned OFF. 5. Therefore, pressure oil which flows to the pilot valve from the pilot pump is blocked by the pilot shut-off solenoid valve (2). 6. When starter cut relay (4) is excited, the circuits between terminal ST (7) in key switch (6) and terminals C of starter 1 (13) and starter 2 (12) are disconnected. 7. Therefore, even if key switch (4) is set to the START position, the engine does not start.

TOKAA90-EN-00

T2-5-30

SECTION 2 SYSTEM Group 5 Electrical System

7 6

21 32

C 9 10

D16

D15 11

TKAA90-02-05-014

234-

Pilot Shut-Off Solenoid Valve Security Relay Starter Cut Relay

TOKAA90-EN-00

567-

Fuse Box 1 Key Switch Terminal ST

8- Fuse Box 2 9- Security Horn 10- Security Horn Relay

T2-5-31

11- Monitor Controller 12- Starter 2 13- Starter 1

SECTION 2 SYSTEM Group 5 Electrical System Radio Circuit 1. The operation on switch panel (2) is displayed on monitor (1) through monitor controller (4). 2. When radio (6) is operated on switch panel (2), the signal is sent to monitor controller (4). 3. Monitor controller (4) sends the signal to radio (6) by using the CAN communication and radio (6) is operated.

Air Conditioner Circuit 1. The operation on switch panel (2) is displayed on monitor (1) through monitor controller (4). 2. When the air conditioner is operated on switch panel (2), the signal is sent to monitor controller (4). 3. Monitor controller (4) sends the signal to air conditioner unit (7) by using the CAN communication and the air conditioner is operated.

TOKAA90-EN-00

T2-5-32

SECTION 2 SYSTEM Group 5 Electrical System

25 35 36

124-

Monitor Switch Panel Monitor Controller

TOKAA90-EN-00

567-

Fuse Box 2 Radio Air Conditioner Unit

T2-5-33

Fuse Box 1

TKAA90-02-05-015

SECTION 2 SYSTEM Group 5 Electrical System (Blank)

TOKAA90-EN-00

T2-5-34

SECTION 2 SYSTEM Group 5 Electrical System Accessory Circuit The major functions and components in the accessory circuit are as follows.  The work light circuit turns on the work lights (left, right, cab upper), rear light, and boom light. (MC2, Switch Panel, Work Light Relay 1, Work Light Relay 2, Work Light Relay 3, Back Light Relay)  The step light circuit turns on the step light. (MC2, Key Switch, Step Light Switch, Step Light Relay)  The wiper/washer circuit operates the wiper including intermittent operation and the washer. (MC2, Switch Panel, Wiper Relay Low, Wiper Relay High 1, Wiper Relay High 2, Washer Relay)  The cab light circuit turns on/off the cab light by shifting the switch or by opening/closing the door. (Cab Light Switch, Door Open/Close Switch)  The sliding fold-in ladder alarm circuit disables the machine operation while lowering the sliding foldin ladder. When the pilot shut-off lever is in the UNLOCK position, the buzzer sounds. (MC2, Sliding Fold-In Ladder Limit Switch, Sliding Fold-In Ladder Relay, Pilot Shut-Off Solenoid Valve, Pilot Shut-Off Lever)

TOKAA90-EN-00

T2-5-35

SECTION 2 SYSTEM Group 5 Electrical System Work Light Circuit Work light (left) (15), work light (right) (16), rear light (9): ON 1. When work light switch (11) is set to the 1 position, current from fuse #7 flows to terminal #B1 of MC2 (14) and switch panel (10), and connects to the ground in switch panel (10). 2. Therefore, work light relay 1 (3) and back light relay (4) are turned ON. Current from fuses #7 and #8 turns on work light (left) (15), work light (right) (16), and rear light (9).

TDC1-02-05-013

3. MC2 (14) sends the signal to monitor controller (13) by using the CAN communication. 4. Monitor controller (13) displays operating condition (19) of work light switch (11) on monitor (12).

Work light (left) (15), work light (right) (16), work light (cab upper) (18), rear light (9), boom light (17): ON 1. When work light switch (11) is set to the 2 position, current from fuse #6 flows to terminal #B3 of MC2 (14) and switch panel (10), and connects to the ground in switch panel (10).

2. Current from fuse #7 flows to terminals #B1 of MC2 (14) and switch panel (10), and connects to the ground in switch panel (10). 3. Therefore, work light relay 1 (3), work light relay 2 (2), work light relay 3 (1), and back light relay (4) are turned ON. Current from fuses #4, #6, #7, and #8 turns on work light (left) (15), work light (right) (16), work light (cab upper) (18), rear light (9), and boom light (17). 4. MC2 (14) sends the signal to monitor controller (13) by using the CAN communication. 5. Monitor controller (13) displays operating condition (19) of work light switch (11) on monitor (12) and changes the monitor (12) screen into the nighttime mode screen.

fNOTE: When the monitor (12) screen is the nighttime mode screen, push 0 on the numerical keypad switch for a few seconds, and then the monitor (12) screen is changed into the daytime mode screen.

TOKAA90-EN-00

T2-5-36

MDAA-01-222

SECTION 2 SYSTEM Group 5 Electrical System 1

5 6 7 8

10 11

16 15

B1 C1 C7

14 13

TKAB-02-05-016

12345-

Work Light Relay 3 Work Light Relay 2 Work Light Relay 1 Back Light Relay From Fuse #4

TOKAA90-EN-00

678910-

From Fuse #6 From Fuse #7 From Fuse #8 Rear Light Switch Panel

1112131415-

T2-5-37

Work Light Switch Monitor Monitor Controller MC2 Work Light (Left)

16- Work Light (Right) 17- Boom Light 18- Work Light (Cab Upper)

SECTION 2 SYSTEM Group 5 Electrical System Step Light Circuit Purpose: The step light circuit turns on/off the step light according to the operation of the key switch and step light switch. Operation: 1. When all following conditions exist, MC2 (1) connects terminal #B9 to the ground inside.  Key Switch (10): ON  Step Light Switch (9): ON 2. Therefore, step light relay (7) is turned ON. Current from fuse #29 turns on step light (6). 3. After key switch (10) is turned OFF and 60 seconds pass, MC2 (1) disconnect terminal #B9 from the ground. Then, step light (6) is turned off.

fNOTE: When key switch (10) is turned OFF, 15 seconds do not pass, and step light switch (9) is turned ON, step light (6) is turned on for 60 seconds.

TOKAA90-EN-00

T2-5-38

SECTION 2 SYSTEM Group 5 Electrical System

2 10 4

9 1

8 7

6 TKAB-02-05-017

123-

MC2 CAN MPDr.

TOKAA90-EN-00

456-

Monitor Controller Monitor Step Light

789-

T2-5-39

Step Light Relay From Fuse #29 Step Light Switch

10- Key Switch

SECTION 2 SYSTEM Group 5 Electrical System Wiper/Washer Circuit Wiper Circuit  Wiper/washer switch: INT. position 1. When wiper/washer switch (1) is set to INT. positions (a, b, c), the signal according to the set interval is sent to MC2 (2).

b a

2. MC2 (2) connects terminal #B2 to the ground in MC2 (2) according to the input interval. 3. Therefore, wiper relay Low (7) is turned ON and OFF repeatedly.

4. When wiper relay Low (7) is ON, current from fuse #9 flows to wiper motor (9) and the wiper is operated. 5. MC2 (2) sends the signal to monitor controller (4) by using the CAN communication. 6. Monitor controller (4) displays operating condition (13) of wiper/washer switch (1) on monitor (5).

TDC1-02-05-014

No. a b c

INT. Position Set Time Slow 8 seconds Middle 6 seconds Fast 3 seconds

 Wiper/washer switch: ON position 1. When wiper/washer switch (1) is set to the ON position, MC2 (2) connects terminal #B12 to the ground in MC2 (2). 2. Therefore, wiper relay High 1 (10) is turned ON.

3. Current from fuse #9 flows to wiper motor (9) and the wiper is continuously operated at fast speed. 4. MC2 (2) sends the signal to monitor controller (4) by using the CAN communication. 5. Monitor controller (4) displays operating condition (13) of wiper/washer switch (1) on monitor (5).

13 MDAA-01-222

TOKAA90-EN-00

T2-5-40

SECTION 2 SYSTEM Group 5 Electrical System  Wiper/washer switch: INT. position 1

4 2 B2 6 12

10 11

TKAB-02-05-018

 Wiper/washer switch: ON position 1

4 2 B12

10 11

TKAB-02-05-019

123-

Wiper/Washer Switch MC2 CAN

TOKAA90-EN-00

456-

Monitor Controller Monitor From Fuse #9

789-

T2-5-41

Wiper Relay Low Wiper Relay High 2 Wiper Motor

10- Wiper Relay High 1 11- Washer Motor 12- Washer Relay

SECTION 2 SYSTEM Group 5 Electrical System Washer Circuit 1. While pushing wiper/washer switch (1), MC2 (2) receives the signals from wiper/washer switch (1). 2. MC2 (2) connects terminal #B11 to the ground inside and washer relay (12) is excited. 3. Current from fuse #9 flows to washer motor (11) and washer liquid is jetted. 4. When pushing wiper/washer switch (1) for 2 seconds or more, MC2 (2) turns ON washer relay (12) and wiper relay High 1 (10).

5. Therefore, the washer and wiper are operated at the same time. TDC1-02-05-014

TOKAA90-EN-00

T2-5-42

SECTION 2 SYSTEM Group 5 Electrical System 1

4 2

B11

10 8 11 9

TKAB-02-05-020

123-

Wiper/Washer Switch MC2 CAN

TOKAA90-EN-00

456-

Monitor Controller Monitor From Fuse #9

789-

T2-5-43

Wiper Relay Low Wiper Relay High 2 Wiper Motor

10- Wiper Relay High 1 11- Washer Motor 12- Washer Relay

SECTION 2 SYSTEM Group 5 Electrical System Cab Light Circuit Cab light switch (4): Door interlocking position (5)

Cab light switch (4): ON position

1. When cab light switch (4) is set to door interlocking position (5), current from fuse #35 flows to door open/close switch (7) through cab light switch (4).

1. When cab light switch (4) is set to ON position (6), current from fuse #35 flows to the ground of cab light switch (4).

2. When the cab door is closed, door open/close switch (7) is turned OFF and cab light switch (4) is disconnected from the ground.

2. Consequently, when cab light switch (4) is in ON position (6), cab light (3) is always turned on.

3. Therefore, cab light (3) is not turned on. 4. When the cab door is opened, door open/close switch (7) is turned ON and cab light switch (4) is connected to the ground. 5. Therefore, cab light (3) is turned on.

TOKAA90-EN-00

T2-5-44

SECTION 2 SYSTEM Group 5 Electrical System

TKAA90-02-05-021

12-

Key Switch Fuse Box 2

TOKAA90-EN-00

34-

Cab Light Cab Light Switch

56-

T2-5-45

Door Interlocking Position ON Position

Door Open/Close Switch

SECTION 2 SYSTEM Group 5 Electrical System Sliding Fold-In Ladder Alarm Circuit Purpose: The sliding fold-in ladder alarm circuit disables the machine operation while lowering the sliding fold-in ladder. When the pilot shut-off lever is in the UNLOCK position, the sliding fold-in ladder alarm circuit sounds the buzzer and displays the sliding fold-in ladder alarm. Operation: 1. When all following conditions exist, MC2 (1) disconnects terminal #B24 from the ground in MC2 (1).  Key Switch (16): ON  Sliding Fold-In Ladder Limit Switch (15): OFF (While lowering the sliding fold-in ladder) 2. As the sliding fold-in ladder relay (9) is turned OFF and the pilot shut-off solenoid valve (14) is disconnected from the ground, the pilot shut-off solenoid valve (14) is turned OFF. 3. Therefore, pressure oil which is supplied from pilot pump (12) to pilot valve (13) is blocked by the pilot shut-off solenoid valve (14). 4. When all following conditions exist, MC1 (6) and MC2 (1) send the signal to monitor controller (3) by using CAN communication (2).  Key Switch (16): ON  Sliding Fold-In Ladder Limit Switch (15): OFF (While lowering the sliding fold-in ladder)  Pilot Shut-Off Switch (10): ON (Pilot Shut-Off Lever: UNLOCK Position) 5. As long as the signal from MC2 (1) is input, the sliding fold-in ladder alarm is displayed on monitor (5). 6. As long as the signal from MC1 (6) is input, monitor controller (3) connects terminal #D7 to the ground. 7. Monitor controller (3) sounds buzzer (4).

TOKAA90-EN-00

T2-5-46

SECTION 2 SYSTEM Group 5 Electrical System

4 5

2 16 D7 15

3 1

D16

B24

14 F13

7 12

10 TKAB-02-05-023

12345-

MC2 CAN Monitor Controller Buzzer Monitor

TOKAA90-EN-00

678910-

MC1 From Fuse #1 Security Relay Sliding Fold-In Ladder Relay Pilot Shut-Off Switch

11121314-

T2-5-47

Pilot Shut-Off Relay Pilot Pump To Pilot Valve Pilot Shut-Off Solenoid Valve

15- Sliding Fold-In Ladder Limit Switch 16- Key Switch

SECTION 2 SYSTEM Group 5 Electrical System (Blank)

TOKAA90-EN-00

T2-5-48

SECTION 2 SYSTEM Group 6 Air Conditioning System Outline Configuration layout of the air conditioning system is illustrated below. Either fresh or re-circulated air is induced into the air conditioner unit by operating the fresh/re-circulated air damper servo motor (6). The induced air flows out of the vents through evaporator (5) or heater core (15) by blower motor (11). Evaporator (5) is a device used to cool the air. Heater core (15) is a device used to warm the air. In the air conditioning system, after the refrigerant is compressed by the compressor, it is sent to evaporator (5) in which the refrigerant expands to cool the air. Heater core (15) warms air by absorbing heat from warmed engine coolant. The temperature is kept at the set temperature by adjusting evaporator (5) and heater core (15).

The vents (operator’s front/rear vent, foot vent, and the front window) can be simultaneously or independently selected by the air vent damper servo motor (1) in accordance with the set-ventilation mode. The front widow and operator’s front vents are manually selectable. The air conditioning controller controls the air conditioning system. The air conditioner controller controls the damper operation by corresponding to the job site conditions such as atmospheric and cab inside air temperatures, coolant temperature, operator’s set temperature, and the set ventilation mode. In addition, the air conditioning controller displays the air conditioner system operation status on the monitor.

6 1

5 2

15 12345-

Air Vent Damper Servo Motor Defroster Vent Rear Vent Front Vent Evaporator

TOKAA90-EN-00

678-

Fresh/Re-circulated Air Damper Servo Motor Re-circulated Air Temperature Sensor Fresh Air Induction Port

9- Re-circulated Air Filter 10- Re-circulated Air Induction Port 11- Blower Motor 12- Power Transistor

T2-6-1

TDAA-05-07-001

11 13141516-

Frost Sensor Air Mix Damper Servo Motor Heater Core Foot Vent

SECTION 2 SYSTEM Group 6 Air Conditioning System Component Layout 1

2 3

4 5

6 7

TKAB-02-06-001

123-

Solar Radiation Sensor Monitor Temperature Control Switch/ Mode Switch

TOKAA90-EN-00

567-

TKAB-02-06-002

AUTO/OFF Switch/Blower Switch Engine Control Dial Key Switch Monitor Controller

89101112-

T2-6-2

Air Conditioner Unit Fresh Air Filter Air Conditioner Controller Ambient Temperature Sensor High/Low Pressure Switch

TKAB-02-06-003

13- Air Conditioner Condenser 14- Receiver Tank 27- Compressor

SECTION 2 SYSTEM Group 6 Air Conditioning System

16 15

20 21

22 23 24 25

TDAA-05-07-028

15- Re-circulated Air Filter 16- Compressor Relay 17- Re-circulated Air Temperature Sensor

TOKAA90-EN-00

18- Fresh/Re-circulated Air Damper Servo Motor 19- Frost Sensor 20- Evaporator

21222324-

T2-6-3

Heater Core Air Mix Damper Servo Motor Air Vent Damper Servo Motor Blower Motor Relay

25- Power Transistor 26- Blower Motor

SECTION 2 SYSTEM Group 6 Air Conditioning System Electrical Circuit Diagram 1

5 14 6 13

TKAB-02-06-004

1234-

Controller Air Vent Damper Servo Motor Air Mix Damper Servo Motor Fresh/Re-circulated Air Damper Servo Motor

TOKAA90-EN-00

5678-

Re-circulated Air temperature Sensor Frost Sensor Power Transistor Monitor Controller

910111213-

T2-6-4

Blower Motor From fuse #3 From fuse #34 From fuse #25 Compressor

1415161718-

High/Low Pressure Switch Ambient Temperature Sensor Solar Radiation Sensor Blower Motor Relay Compressor Relay

SECTION 2 SYSTEM Group 6 Air Conditioning System Functions of Main Parts The functions of the main parts for the air conditioner are described below. The connector No. is shown in the parentheses after the part name.  Controller The controller controls the air conditioning system. The controller has the following functions.  The operator’s instructions are input by the switches.  The air and coolant temperature are detected by the sensors.  Input the air conditioner unit conditions.  The blower motor and compressor are controlled by operating the relays.  The air conditioner operating conditions are displayed on the monitor panel.

TDC1-05-07-002

 Power Transistor (CN7) The power transistor is an electric switch to control blower motor voltage.

TDC1-05-07-003

 Blower Motor Relay (CN3) The blower motor relay supplies 24 volts power to the blower motor when the air conditioner is operated. The blower motor relay is turned ON when excited by the current from terminal #30B in controller. TDC1-05-07-004

 Compressor Relay (CN4) The compressor relay supplies 24 volts power to the compressor clutch when the air conditioner is operated. The compressor relay is turned ON when excited by the current from terminal #29B in controller. TDC1-05-07-005

TOKAA90-EN-00

T2-6-5

SECTION 2 SYSTEM Group 6 Air Conditioning System  Frost Sensor (CN12) The frost sensor detects the fin temperature which is cooled by the evaporator. When the temperature is higher than 3 °C (approx. 4.2 kΩ), the controller turns the compressor relay ON. When the temperature is 2 °C (approx. 4.5 kΩ) or less, the controller turns OFF the compressor relay. Therefore, the evaporator in the air conditioner unit is prevented from freezing. The electrical resistance in the frost sensor is 100 Ω to 115 kΩ.

 High/Low Pressure Switch (CN14) The high/low pressure switch controls the compressor clutch solenoid while detecting the compressor circuit pressure. The high/low pressure switch consists of a pressure gauge and a switch. The pressure gauge detects the low pressure range (0.196 MPa to 0.216 MPa) and the surge pressure range (2.55 MPa to 3.14 MPa). When the circuit pressure decreases to the low pressure range or increases to the surge pressure range, the pressure gauge turns OFF the switch. Therefore, the compressor operation stops. If the pressure decreases to the low range, a lack of refrigerant is suspected. Therefore, damage to the compressor due to a lack of refrigerant is prevented. When the pressure increases to the surge range, damage to the air conditioner circuit parts due to excessively high circuit pressure is prevented.

 Re-circulated Air Temperature Sensor (CN11) The re-circulated air temperature sensor detects the temperatures (0 to 25 °C) around the re-circulated air inlet as the interior air temperatures and converts them to the electrical resistance values. The temperatures 0 °C to 25 °C corresponds to a resistance of 1.645 kΩ (0 °C) to 5 kΩ (25 °C) respectively. The electrical resistance in the re-circulated air temperature sensor is 300 Ω to 430 kΩ.

 Ambient Temperature Sensor (CN15) The ambient temperature sensor detects the temperature at the side of the air conditioner condenser as the outdoor air temperature, and converts the temperature to the electrical resistance value. The electrical resistance in the ambient temperature sensor is 100 Ω to 210 kΩ.

TOKAA90-EN-00

T2-6-6

TDC1-05-07-006

TDC1-05-07-007

TDAA-05-07-014

TDC1-05-07-008

TDC1-05-07-009

SECTION 2 SYSTEM Group 6 Air Conditioning System  Solar Radiation Sensor (CN16) The solar radiation sensor converts the amount of solar radiation (illumination intensity) at the cab front to the current values.

TDC1-05-07-010

 Fresh/Re-circulated Air Damper Servo Motor (CN10) The fresh/re-circulated air damper servo motor opens or closes the fresh/re-circulated air selection louvers. The damper consists of a motor, link mechanism, and position sensing switch. The motor opens or closes the fresh/recirculated air selection louvers via the link mechanism.

TDC1-05-07-011

TOKAA90-EN-00

T2-6-7

SECTION 2 SYSTEM Group 6 Air Conditioning System  Air Mix Damper Servo Motor (CN9) The air mix damper servo motor controls opening/closing of the air mixing door in response to the set temperature. This servo motor consists of a motor, link mechanism, and potentiometer. The motor opens or closes the air mix door via the link mechanism. The potentiometer converts the link movements (the mix door strokes) to the voltage. Both ends of the potentiometer are energized by 5 V from terminals #7D (+) and #25E (-) in controller. The voltage (0.5 to 4.5 V) corresponding to the link movement is output from the center terminal of the potentiometer, and is input to terminal #19B in controller. The set temperature is determined by temperature UP/DOWN signal from the controller. The controller calculates voltage (Vr) corresponding the link position for the set temperature. Further more, the controller checks the air mix door position by voltage (Vf ) from the potentiometer. Then, after the controller decides the motor rotational direction (polarity of motor) based on the differential voltage between Vr and Vf, the controller sends out the current from terminals #15B and #16B. The controller drives the motor until voltage (Vf ) becomes equal to voltage (Vr).

TOKAA90-EN-00

T2-6-8

TDC1-05-07-012

SECTION 2 SYSTEM Group 6 Air Conditioning System  Air Vent Damper Servo Motor (CN8) The air vent damper servo motor opens or closes the front and rear air vent, foot vent, and defroster vent louvers. The damper consists of a motor, link mechanism, and potentiometer. The motor opens or closes vent louvers via the link mechanism. The potentiometer converts the link movements (vent louvers strokes) to the voltage. Both ends of the potentiometer are energized by 5 V from terminals #7C (+) and #25D (-) in controller. The voltage (0.5 to 4.5 V) corresponding to the link movement is output from the center terminal of the potentiometer, and is input to terminal #20B in controller. Depending on the MODE switch set position, vent louvers are operated as shown below:  Front Air Vent: Open, Rear Air Vent: Close, Foot Air Vent: Close  Front Air Vent: Open, Rear Air Vent: Open, Foot Air Vent: Close  Front Air Vent: Open, Rear Air Vent: Open, Foot Air Vent: Open  Front Air Vent: Close, Rear Air Vent: Close, Foot Air Vent: Open The controller calculates the louvers position of front and rear vent that are corresponding to selected switch position as the voltage (Vr) of potentiometer. Furthermore, the controller checks the vent louvers positions by receiving voltage (Vf ) from the potentiometer. Then, after the controller decides the motor rotational direction (polarity of motor) based on the differential voltage between Vr and Vf. The controller sends out the current from terminals #31B and #32B. The controller drives the motor until voltage (Vf ) becomes equal to voltage (Vr).

TOKAA90-EN-00

T2-6-9

TDC1-05-07-013

SECTION 2 SYSTEM Group 6 Air Conditioning System (Blank)

TOKAA90-EN-00

T2-6-10

MEMO

TOKAA90-EN-00

MEMO

TOKAA90-EN-00

SECTION 3

COMPONENT OPERATION CONTENTS Group 1 Pump Device

Outline..................................................................................... T3-1-1 Main Pump, Fan Pump....................................................... T3-1-2 Regulator for Main Pump.................................................. T3-1-4 Fan Pump Regulator.........................................................T3-1-12 Main Pump Control Solenoid Valve, Fan Pump Control Solenoid Valve..........................T3-1-28 Pilot Pump, Transmission Lubrication Pump...........T3-1-30 Pump Delivery Pressure Sensor....................................T3-1-30 Regulator Pressure (Flow Rate Control Pressure) Sensor............................................................T3-1-30

Group 2 Swing Device

Outline..................................................................................... T3-2-1 Swing Reduction Gear....................................................... T3-2-2 Swing Motor.......................................................................... T3-2-3 Swing Parking Brake........................................................... T3-2-4 Valve Unit................................................................................ T3-2-7

Group 3 Control Valve

Outline..................................................................................... T3-3-1 Main Control Valve.............................................................. T3-3-2 Swing Control Valve..........................................................T3-3-12 Hydraulic Circuit.................................................................T3-3-16 Flow Combiner Valve........................................................T3-3-22 Main Relief Valve................................................................T3-3-24 Overload Relief Valve (with Make-Up Function).....T3-3-28 Overload Relief Valve (Low Pressure)..........................T3-3-32 Regenerative Valve............................................................T3-3-34 Flow Rate Control Valve...................................................T3-3-40 Boom Lower Meter-In Cut Valve...................................T3-3-44 Anti-Drift Valve....................................................................T3-3-48 Bypass Shut-Out Valve.....................................................T3-3-52

Parking Brake......................................................................... T3-5-6 Travel Brake Valve................................................................ T3-5-8 Counterbalance Valve, Check Valve.............................T3-5-10 Overload Relief Valve........................................................T3-5-14 Travel Motor Displacement Angle Control Valve..................................................................T3-5-18

Group 6 Signal Control Valve

Outline..................................................................................... T3-6-1 Pilot Port.................................................................................. T3-6-2 Shuttle Valve.......................................................................... T3-6-7 Shockless Valve...................................................................T3-6-10 Flow Combiner Valve Control Spool, Swing Parking Brake Release Spool.......................T3-6-14

Group 7 Others (Upperstructure)

Pilot Shut-Off Solenoid Valve........................................... T3-7-1 Solenoid Valve....................................................................... T3-7-3 Fan Motor............................................................................... T3-7-5 Fan Valve................................................................................. T3-7-6 Pilot Relief Valve.................................................................T3-7-10 Shockless Valve...................................................................T3-7-11 Accumulator........................................................................T3-7-13 Auto-Lubrication System................................................T3-7-14 Distribution Valve (Quicklub Lubrication System) (Standard).......................................................T3-7-16 Distribution Valve (Centro Matic Lubrication System) (Option)...........................................................T3-7-19

Group 8 Others (Undercarriage)

Swing Bearing....................................................................... T3-8-1 Center Joint............................................................................ T3-8-2 Track Adjuster........................................................................ T3-8-3

Group 4 Pilot Valve

Outline..................................................................................... T3-4-1 Operation (Front Attachment/Swing and Travel Pilot Valves).......................................................... T3-4-3 Operation (Bucket Open/Close Pilot Valve: only Loading Shovel)..................................................T3-4-11 Shockless Function (Only for Travel Pilot Valve)......T3-4-18

Group 5 Travel Device

Outline..................................................................................... T3-5-1 Travel Reduction Gear........................................................ T3-5-2 Travel Motor........................................................................... T3-5-4

TOKAA90-EN-00

KAB90T-3-1

(Blank)

TOKAA90-EN-00

KAB90T-3-2

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Outline The pump device consists of pump transmission (2), main pumps (3 used) (pump 1 (9), pump 2 (3), pump 3 (11)), and 3-unit pump (8). Pump transmission (2) distributes the engine output power by using gears and transmits to each pump. Main pumps (3 used) (3, 9, 11) are swash plate type variable displacement plunger pumps, and supply high pressure oil.

Viewed from the pump transmission (2) side in 3-unit pump (8), the pumps are arranged as follows:  Fan pump (5) (swash plate type variable displacement plunger pump)  Pilot pump (6) (gear pump)  Transmission lubrication pump (7) (gear pump)

11 3

9 7

TKAB-03-01-001

8 1234-

Pump 2 Regulator Pump Transmission Pump 2 Fan Pump Regulator

TOKAA90-EN-00

567-

Fan Pump Pilot Pump Transmission Lubrication Pump

891011-

T3-1-1

3-Unit Pump Pump 1 Pump 1 Regulator Pump 3

12- Pump 3 Regulator

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Main Pump, Fan Pump Outline

Operational Principle

Cylinder blocks (3) are connected to shafts (1) of the main pump and fan pump by a spline joint. Plungers (2) are inserted into cylinder block (3). The engine output power is transmitted to shaft (1) via the pump transmission.

1. Engine torque is transmitted to shaft (1). 2. When shaft (1) turns, plungers (2) turn with cylinder block (3). 3. Plungers (2) slide on swash plate (5). 4. Plungers (2) reciprocate in the cylinder block (3) bore. 5. Hydraulic oil is drawn and delivered by this reciprocation.

Main Pump 2

TKAB-03-01-002

Fan Pump 2

5 12-

Shaft Plunger

TOKAA90-EN-00

34-

Cylinder Block Shoe Plate

TKAB-03-01-003

4 5-

T3-1-2

Swash Plate

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Increasing and Decreasing Flow Rate

1. Changing inclination of swash plate (3) increases or decreases the pump delivery flow rate. 2. Servo piston (2) is moved by pressure oil from the regulator. 3. As swash plate (3) is connected to servo piston (2), the displacement angle of swash plate (3) is changed according to the movement of servo piston (2).

4. When the displacement angle of swash plate (3) increases, stroke (S) of plungers (4) is longer. As pressure oil which is delivered by plungers (4) increases, the pump delivery flow rate increases. 4 1

When the displacement angle of swash plate (3) increases, the pump delivery flow rate increases.

3 TKAB-03-01-004

TKAB-03-01-005

When the displacement angle of swash plate (3) decreases, the pump delivery flow rate decreases.

TKAB-03-01-006 S-

Stroke

12-

Shaft Servo Piston

TOKAA90-EN-00

34-

Swash Plate Plunger

56-

T3-1-3

Cylinder Block Valve Plate

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Regulator for Main Pump The regulator is installed on the upper part of main pump (MP), moves servo piston (11), and controls the main pump (MP) flow rate by movement of servo piston (11). The flow rate control is performed by increasing or decreasing the flow rate control pressure Pi by the pump control solenoid valve (4). The own pump delivery pressure P1 acts on spool (2) via check valve (6), and always acts on small chamber (12) of servo piston (11).

Primary pilot pressure Psv from pilot pump (PP) is reduced by the pump control solenoid valve (4) and acts on pilot piston (3) as the flow rate control pressure Pi. Primary pilot pressure Psv is combined with the own pump delivery pressure P1 through check valve (5).

5 Psv

7 Pi

9 10 12

TOKAA90-EN-00

T3-1-4

P1 MP

TKAB-03-01-007

SECTION 3 COMPONENT OPERATION Group 1 Pump Device c

Detail c

TKAB-03-01-012

Psv 9

3 6

MP- Main Pump

PP- Pilot Pump

CV- To Control Valve

Psv- Primary Pilot Pressure

Pi-

P1- Own Pump Delivery Pressure

Displacement Angle Increase

Displacement Angle Decrease

1234-

Sleeve Spool Pilot Piston Pump Control Solenoid Valve

5678-

Check Valve Check Valve Spring Pin

TOKAA90-EN-00

Flow Rate Control Pressure

9101112-

T3-1-5

Pin Feedback Lever Servo Piston Small Chamber

TKAB-03-01-008

13- Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Control by Flow Rate Control Pressure of Pump Control Solenoid Valve  Minimum flow rate (Flow rate control pressure Pi is zero.) 4. As servo piston (11) is moved, feedback lever (10) turns counterclockwise around pin (9).

1. When the flow rate control pressure Pi from the pump control solenoid valve (4) is zero, spool (2) is pushed to the left by spring (7).

5. As the end of feedback lever (10) is connected to sleeve (1) by pin (8), sleeve (1) is moved to the left.

2. The own pump delivery pressure P1 acts on large chamber (13) of servo piston (11) via check valve (6), sleeve (1), and spool (2).

6. Servo piston (11) moves until the open part between sleeve (1) and spool (2) is closed. Servo piston (11) stops when the open part is completely closed.

3. The own pump delivery pressure P1 always acts on small chamber (12) of servo piston (11). Due to the difference in the pressure receiving areas, servo piston (11) is moved to the right.

7. As described above, the pump displacement angle of the swash plate is minimized and the pump delivery flow rate is minimized. CV

5 Psv

6 4

Pi 7

8 9

10 12

TOKAA90-EN-00

T3-1-6

P1 MP

TKAB-03-01-009

SECTION 3 COMPONENT OPERATION Group 1 Pump Device c

Detail c

TKAB-03-01-012

Psv

10 3 6

MP- Main Pump

PP- Pilot Pump

CV- To Control Valve

Psv- Primary Pilot Pressure

Pi-

P1- Own Pump Delivery Pressure

Displacement Angle Increase

Displacement Angle Decrease

1234-

Sleeve Spool Pilot Piston Pump Control Solenoid Valve

5678-

Check Valve Check Valve Spring Pin

TOKAA90-EN-00

Flow Rate Control Pressure

9101112-

T3-1-7

Pin Feedback Lever Servo Piston Small Chamber

TKAB-03-01-010

13- Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device  Flow Rate Increase (Flow rate control pressure Pi increases.) 5. When servo piston (11) is moved, feedback lever (10) turns clockwise around pin (9).

1. The pump control solenoid valve (4) controls to increase the flow rate control pressure Pi according to the signal from MC (Main controller).

6. As the end of feedback lever (10) is connected to sleeve (1) by pin (8), sleeve (1) is moved to the right.

2. Pilot piston (3) moves spool (2) to the right by the flow rate control pressure Pi until the flow rate control pressure Pi balances with the spring (7) force.

7. Servo piston (11) moves until the open part between sleeve (1) and spool (2) is closed. Servo piston (11) stops when the open part is completely closed.

3. As spool (2) is moved, large chamber (13) of servo piston (11) is connected to the hydraulic oil tank via inside of spool (2).

8. As described above, the pump displacement angle of the swash plate 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.

4. As the own pump delivery pressure P1 always acts on small chamber (12) of servo piston (11), servo piston (11) is moved to the left and pressure oil in large chamber (13) returns to the hydraulic oil tank.

Psv

CV 5

4 6 Pi 3 7 8

9 1

TOKAA90-EN-00

T3-1-8

P1 MP

TKAB-03-01-035

SECTION 3 COMPONENT OPERATION Group 1 Pump Device c

Detail c

TKAB-03-01-012

Psv

10 3 6

MP- Main Pump

PP- Pilot Pump

CV- To Control Valve

Psv- Primary Pilot Pressure

Pi-

P1- Own Pump Delivery Pressure

Displacement Angle Increase

Displacement Angle Decrease

1234-

Sleeve Spool Pilot Piston Pump Control Solenoid Valve

5678-

Check Valve Check Valve Spring Pin

TOKAA90-EN-00

Flow Rate Control Pressure

9101112-

T3-1-9

Pin Feedback Lever Servo Piston Small Chamber

TKAB-03-01-011

13- Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device  Flow Rate Decrease (Flow rate control pressure Pi decreases.) 6. As servo piston (11) is moved to the right, feedback lever (10) turns counterclockwise around pin (9).

1. The pump control solenoid valve (4) controls to decrease the flow rate control pressure Pi according to the signal from MC (Main controller).

7. As the end of feedback lever (10) is connected to sleeve (1) by pin (8), sleeve (1) is moved to the left.

2. Spool (2) is moved to the left until the flow rate control pressure Pi balances with the spring (7) force.

8. Servo piston (11) moves until the open part between sleeve (1) and spool (2) is closed. Servo piston (11) stops when the open part is completely closed.

3. Pressure oil acting on pilot piston (3) is returned to the hydraulic oil tank through the pump control solenoid valve (4).

9. As described above, the pump displacement angle of the swash plate 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.

4. As spool (2) is moved, the own pump delivery pressure P1 acts on large chamber (13) of servo piston (11) via check valve (6), sleeve (1), and spool (2). 5. The own pump delivery pressure P1 always acts on small chamber (12) of servo piston (11). Due to the difference in the pressure receiving areas, servo piston (11) is moved to the right.

5 Psv

6 4

8 9

10 12

TOKAA90-EN-00

T3-1-10

P1 MP

TKAB-03-01-009

SECTION 3 COMPONENT OPERATION Group 1 Pump Device c

Detail c

TKAB-03-01-012

Psv

10 3 6

MP- Main Pump Psv- Primary Pilot Pressure a- Displacement Angle Increase

PP- Pilot Pump Pi- Flow Rate Control Pressure b- Displacement Angle Decrease

CV- To Control Valve P1- Own Pump Delivery Pressure

1234-

5678-

9101112-

Sleeve Spool Pilot Piston Pump Control Solenoid Valve

TOKAA90-EN-00

Check Valve Check Valve Spring Pin

T3-1-11

Pin Feedback Lever Servo Piston Small Chamber

TKAB-03-01-013

13- Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Fan Pump Regulator

The regulator is installed on the upper part of fan pump (FP) and controls the flow rate of fan pump (FP). The flow rate control is performed by increasing or decreasing the flow rate control pressure Pi by the fan pump control solenoid valve (17). The own pump delivery pressure P3 always acts on compensating piston (1), spool (2), and small chamber (24) of servo piston (15). When the fan pump control solenoid valve (17) is activated, primary pilot pressure Pr from pilot pump (PP) is reduced and is routed as the flow rate control pressure Pi. The flow rate control pressure Pi acts on pilot piston (22). TKAB-03-01-015

Pi 22 2

9, 10 25

P3 FP

FP- Fan Pump P3- Own Pump Delivery Pressure a- Displacement Angle Increase

PP- Pilot Pump Pi- Flow Rate Control Pressure b Displacement Angle Decrease

FM- To Fan Motor Pr- Primary Pilot Pressure

1234567-

891011121314-

15- Servo Piston 16- Spool 17- Fan Pump Control Solenoid Valve 18- Lever 1 19- Pin 20- Spring

Compensating Piston Spool Sleeve Lever 2 Pin Pin Pin

TOKAA90-EN-00

Hole Inner Spring Outer Spring Compensating Rod Pin Feedback Lever Pin

T3-1-12

TKAB-03-01-014

2122232425-

Pin Pilot Piston Hole Small Chamber Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Section A

14 13 a

b 12

TKAB-03-01-016

Section B

TOKAA90-EN-00

14 13

T3-1-13

TKAB-03-01-017

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Link Mechanism The movement of pilot piston (22) is transmitted to lever 1 (18) via pin (21), and turns lever 1 (18) around pin (19) which is secured to supporting plug (27) The movement of compensating rod (11) is transmitted to lever 2 (4) via pin (12), and turns lever 2 (4) around pin (5) which is secured to housing (26) Pin (7) is installed in feedback lever (13). The both ends of pin (7) are inserted into holes (23, 8) of lever 1 (18) and lever 2 (4).

Therefore, when lever 1 (18) or lever 2 (4) turns, pin (7) comes in contact with hole (23) of lever 1 (18) or hole (8) of lever 2 (4). Feedback lever (13) turns around pin (14) which is installed in servo piston (15). As servo piston (15) is moved, feedback lever (13) is moved via pin (14). At this time, as lever 1 (18) and lever 2 (4) do not turn, feedback lever (13) turns around pin (7).

fNOTE:

26 5 11

: Displacement Angle Decrease : Displacement Angle Increase

8 13 6 7 18 23

19 21 27

14 22 15

24567-

Spool Lever 2 Pin Pin Pin

TOKAA90-EN-00

811121314-

Hole Compensating Rod Pin Feedback Lever Pin

TKAB-03-01-018

1518192122-

T3-1-14

Servo Piston Lever 1 Pin Pin Pilot Piston

23- Hole 26- Housing 27- Supporting Plug

SECTION 3 COMPONENT OPERATION Group 1 Pump Device (Blank)

TOKAA90-EN-00

T3-1-15

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Control by Flow Rate Control Pressure of Fan Pump Control Solenoid Valve  Flow Rate Decrease (Flow rate control pressure Pi increases.) 1. When the fan pump control solenoid valve (17) is activated, the flow rate control pressure Pi acts on pilot piston (22) via spool (16) according to the operation amount of the fan pump control solenoid valve (17).

9. As described above, the pump delivery flow rate is decreased according to the increased amount of the flow rate control pressure Pi.

fNOTE: Refer to SYSTEM/Hydraulic System/Pilot Circuit.

2. When the flow rate control pressure Pi increases, pilot piston (22) is moved to the right until the flow rate control pressure Pi balances with the spring (20) force.

3. Pilot piston (22) moves lever 1 (18) via pin (21). Lever 1 (18) turns counterclockwise around pin (19) which is secured to supporting plug (27). 4. Pin (7) which is installed in feedback lever (13) is inserted into hole (23) of lever 1 (18). Therefore, feedback lever (13) turns clockwise around pin (14) by turning lever 1 (18). Then, spool (2) is moved to the right. 5. As spool (2) is moved, the own pump delivery pressure P3 acts on large chamber (25) of servo piston (15) via spool (2). The own pump delivery pressure P3 also acts on small chamber (24). Due to the difference in the pressure receiving areas, servo piston (15) is moved to the right. 6. The pump displacement angle decreases (b) according to the movement of servo piston (15), and the pump delivery flow rate decreases.

Pi Q-

Flow Rate

Pi-

Flow Rate Control Pressure

Pr Pi

7. As servo piston (15) is moved, feedback lever (13) is moved via pin (14). As pilot piston (22) and lever 1 (18) do not move, feedback lever (13) turns counterclockwise around pin (7). Then, spool (2) is moved to the left.

8. When the open part between spool (2) and sleeve (3) is completely closed, the own pump delivery pressure P3 does not act on large chamber (25) of servo piston (15). Then, servo piston (15) is stopped moving.

3 2

24 PP

14 FP

TKAB-03-01-019

TOKAA90-EN-00

T3-1-16

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Section A

14 13

TKAB-03-01-020

Section B

23 Pi

TOKAA90-EN-00

T3-1-17

TKAB-03-01-021

SECTION 3 COMPONENT OPERATION Group 1 Pump Device

7 18 23 2

19 21 27

14 22 15

TKAB-03-01-018

FP- Fan Pump P3- Own Pump Delivery Pressure a- Displacement Angle Increase

PP- Pilot Pump Pi- Flow Rate Control Pressure b Displacement Angle Decrease

FM- To Fan Motor Pr- Primary Pilot Pressure

1234567-

891011121314-

15- Servo Piston 16- Spool 17- Fan Pump Control Solenoid Valve 18- Lever 1 19- Pin 20- Spring

Compensating Piston Spool Sleeve Lever 2 Pin Pin Pin

TOKAA90-EN-00

Hole Inner Spring Outer Spring Compensating Rod Pin Feedback Lever Pin

T3-1-18

2122232425-

Pin Pilot Piston Hole Small Chamber Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device (Blank)

TOKAA90-EN-00

T3-1-19

SECTION 3 COMPONENT OPERATION Group 1 Pump Device  Flow Rate Increase (Flow rate control pressure Pi decreases.) 1. When the fan pump control solenoid valve (17) is activated, the flow rate control pressure Pi acts on pilot piston (22) via spool (16) according to the operation amount of the fan pump control solenoid valve (17).

9. As described above, the pump delivery flow rate is increased according to the decreased amount of the flow rate control pressure Pi.

fNOTE: Refer to SYSTEM/Hydraulic System/Pilot Circuit.

2. When the flow rate control pressure Pi decreases, pilot piston (22) is moved to the left until the flow rate control pressure Pi balances with the spring (20) force.

3. Pilot piston (22) moves lever 1 (18) via pin (21). Lever 1 (18) turns clockwise around pin (19) which is secured to supporting plug (27). 4. Pin (7) which is installed in feedback lever (13) is inserted into hole (23) of lever 1 (18). Therefore, feedback lever (13) turns counterclockwise around pin (14) by turning lever 1 (18). Then, spool (2) is moved to the left. Pi

5. As spool (2) is moved, large chamber (25) of servo piston (15) is connected to the hydraulic oil tank via spool (2). As the own pump delivery pressure P3 acts on small chamber (24), servo piston (15) is moved to the left.

Q-

Flow Rate

Pi-

6. The pump displacement angle increases (a) according to the movement of servo piston (15), and the pump delivery flow rate increases.

Flow Rate Control Pressure

7. As servo piston (15) is moved, feedback lever (13) is moved via pin (14). As pilot piston (22) and lever 1 (18) do not move, feedback lever (13) turns clockwise around pin (7). Then, spool (2) is moved to the right.

Pi 17 3

2 13

8. When the open part between spool (2) and sleeve (3) is completely closed, large chamber (25) of servo piston (15) is disconnected from the hydraulic oil tank. Then, servo piston (15) is stopped moving.

24 PP

14 FP

TKAB-03-01-022

FP- Fan Pump P3- Own Pump Delivery Pressure a- Displacement Angle Increase

PP- Pilot Pump Pi- Flow Rate Control Pressure b Displacement Angle Decrease

FM- To Fan Motor Pr- Primary Pilot Pressure

1234567-

891011121314-

15- Servo Piston 16- Spool 17- Fan Pump Control Solenoid Valve 18- Lever 1 19- Pin 20- Spring

Compensating Piston Spool Sleeve Lever 2 Pin Pin Pin

TOKAA90-EN-00

Hole Inner Spring Outer Spring Compensating Rod Pin Feedback Lever Pin

T3-1-20

2122232425-

Pin Pilot Piston Hole Small Chamber Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Section A

14 13

TKAB-03-01-023

Section B

23 Pi

TOKAA90-EN-00

T3-1-21

TKAB-03-01-024

SECTION 3 COMPONENT OPERATION Group 1 Pump Device

7 18 23 2

19 21 27

14 22 15

24567-

Spool Lever 2 Pin Pin Pin

TOKAA90-EN-00

811121314-

Hole Compensating Rod Pin Feedback Lever Pin

TKAB-03-01-018

1518192122-

T3-1-22

Servo Piston Lever 1 Pin Pin Pilot Piston

23- Hole 26- Housing 27- Supporting Plug

SECTION 3 COMPONENT OPERATION Group 1 Pump Device (Blank)

TOKAA90-EN-00

T3-1-23

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Control by Own Pump Delivery Pressure

fNOTE: This control is performed only when the engine

speed increases over the rated speed when starting and so on.

 Flow Rate Decrease 1. When the own pump delivery pressure P3 increases from C to D, compensating piston (1) moves compensating rod (11) to the right until the own pump delivery pressure P3 balances with the force of outer spring (10) and inner spring (9).

2. Compensating rod (11) moves lever 2 (4) via pin (12). Lever 2 (4) turns counterclockwise around pin (5) which is secured to housing (26).

9. As described above, the pump delivery flow rate decreases from A to B.

3. Pin (7) which is installed in feedback lever (13) is inserted into hole (8) of lever 2 (4). Therefore, feedback lever (13) turns clockwise around pin (14) by turning lever 2 (4). Then, spool (2) is moved to the right.

A B

4. As spool (2) is moved, the own pump delivery pressure P3 acts on large chamber (25) of servo piston (15) via spool (2). The own pump delivery pressure P3 also acts on small chamber (24). Due to the difference in the pressure receiving areas, servo piston (15) is moved to the right. 5. The pump displacement angle decreases (b) according to the movement of servo piston (15), and the pump delivery flow rate decreases.

C Q-

Flow Rate

6. The own pump delivery pressure P3 acts on compensating piston (1). Then, even when servo piston (15) is moved, compensating rod (11) and lever 2 (4) do not move.

P3- Own Pump Delivery Pressure

FM Pr

7. As servo piston (15) is moved, feedback lever (13) is moved via pin (14). As compensating rod (11) and lever 2 (4) do not move, feedback lever (13) turns counterclockwise around pin (7). Then, spool (2) is moved to the left.

3 2 13

24 PP

9, 10 25 15

14 FP

TKAB-03-01-025

TOKAA90-EN-00

T3-1-24

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Section A

14 13

TKAB-03-01-026

26 5 11

8 13 6 7

TOKAA90-EN-00

TKAB-03-01-018

T3-1-25

SECTION 3 COMPONENT OPERATION Group 1 Pump Device  Flow Rate Increase Q

1. When the own pump delivery pressure P3 decreases from D to C, compensating piston (1) and compensating rod (11) are moved to the left until the own pump delivery pressure P3 balances with the force of outer spring (10) and inner spring (9).

A B

2. Compensating rod (11) moves lever 2 (4) via pin (12). Lever 2 (4) turns clockwise around pin (5) which is secured to housing (26). 3. Pin (7) which is installed in feedback lever (13) is inserted into hole (8) of lever 2 (4). Therefore, feedback lever (13) turns counterclockwise around pin (14) by turning lever 2 (4). Then, spool (2) is moved to the left.

C Q-

Flow Rate

4. As spool (2) is moved, large chamber (25) of servo piston (15) is connected to the hydraulic oil tank via spool (2). As the own pump delivery pressure P3 acts on small chamber (24), servo piston (15) is moved to the left.

FM Pr

5. The pump displacement angle increases (a) according to the movement of servo piston (15), and the pump delivery flow rate increases.

6. As servo piston (15) is moved, feedback lever (13) is also moved via pin (14). As compensating rod (11) and lever 2 (4) do not move, feedback lever (13) turns clockwise around pin (7). Then, spool (2) is moved to the right.

2 13

7. When the open part between spool (2) and sleeve (3) is completely closed, large chamber (25) of servo piston (15) is disconnected from the hydraulic oil tank. Then, servo piston (15) is stopped moving.

24 PP

9, 10 25 15

FP- Fan Pump P3- Own Pump Delivery Pressure a- Displacement Angle Increase

PP- Pilot Pump Pi- Flow Rate Control Pressure b Displacement Angle Decrease

FM- To Fan Motor Pr- Primary Pilot Pressure

1234567-

891011121314-

15- Servo Piston 16- Spool 17- Fan Pump Control Solenoid Valve 18- Lever 1 19- Pin 20- Spring

TOKAA90-EN-00

Hole Inner Spring Outer Spring Compensating Rod Pin Feedback Lever Pin

14 FP

TKAB-03-01-027

8. As described above, the pump delivery flow rate increases from B to A.

Compensating Piston Spool Sleeve Lever 2 Pin Pin Pin

P3- Own Pump Delivery Pressure

T3-1-26

2122232425-

Pin Pilot Piston Hole Small Chamber Large Chamber

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Section A

14 13

FP TKAB-03-01-028

26 5 11

8 13

TOKAA90-EN-00

TKAB-03-01-018

T3-1-27

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Main Pump Control Solenoid Valve, Fan Pump Control Solenoid Valve The pump control solenoid valve is installed on the regulators for the main pumps and for the fan pump. The pump control solenoid valve supplies the flow rate control pressure to the regulator and controls the pump delivery flow rate. Operation  Not operating state 1. When solenoid (4) of the pump control solenoid valve is not activated, spool (1) is pushed to the right by spring (3). At this time, port P is disconnected from output port (a) by spool (1).

7. Consequently, as port P is disconnceted from output port (a) by spool (1), pressure at output port (a) stops increasing.

2. Output port (a) is connected to port T through the notch of spool (1).

Fs : Solenoid (4) Force Pi : Pressure at Output Port (a)

 Operating state 1. When current flows to solenoid (4) from MC1, solenoid (4) is excited and pushes spool (1) to the left.

A, B: Pressure Receiving Area of Spool (1) S : Spring (3) Force (Force pushing spool (1) to the right)

2. port P is connected to output port (a) through the notch of spool (1). 3. Pressure at output port (a) begins to increase. 4. Pressure receiving area B is larger than pressure receiving area A as for spool (1). When oil pressure acts on spool (1), spool (1) is move to the right due to the difference in the pressure receiving areas. 5. When pressure Pi at output port (a) is low, the following formula exists, Fs > (B - A) × Pi + S. Then, spool (1) is pushed to the left. (Fs is the force pushing spool (1) to the left. (B - A) × Pi + S is the force pushing spool (1) to the right.) 6. When pressure Pi at output port (a) increases, the following formula exists, Fs < (B - A) × Pi + S. Then, spool (1) is moved to the right.

TOKAA90-EN-00

T3-1-28

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Not operating state: 2

TKAB-03-01-029

Output Port

P-

Port P

T-

Port T

Spool

Sleeve

Spring

Solenoid

Operating state: 2

T TKAB-03-01-030

TOKAA90-EN-00

T3-1-29

SECTION 3 COMPONENT OPERATION Group 1 Pump Device Pilot Pump, Transmission Lubrication Pump Pilot pump (2) and transmission lubrication pump (3) are gear pumps. 12-

Fan Pump Pilot Pump

Transmission Lubrication Pump

Inside of the gear pump, drive gear (4) is driven by the engine via the transmission, which rotates driven gear (5) as they are meshed together. Hydraulic oil which has drawn from suction port (a) to the gear pump is delivered to deliery port (b) through the clearance between gear and casing. 45-

Drive Gear Driven Gear

ab-

2 TKAB-03-01-031

Suction Port Delivery Port

b TKAB-03-01-032

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 (9), diaphragm (9) is deformed. The deformation of diaphragm (9) is detected as electrical signals. 678-

Ground Output Power Source (5 V)

Diaphragm (Pressure Receiving Area)

7 8

TKAB-03-01-033

Regulator Pressure (Flow Rate Control Pressure) Sensor The regulator pressure (flow rate control pressure) sensor detects the pump regulator pressure, which is used in order to control various operations. When oil pressure is applied to diaphragm (10), diaphragm (10) is deformed. The deformation of diaphragm (10) is detected as electrical signals.

TKAB-03-01-034 10- Diaphragm (Pressure Receiving Area) 11- Ground

TOKAA90-EN-00

12- Output 13- Power Source (5 V)

T3-1-30

SECTION 3 COMPONENT OPERATION Group 2 Swing Device Swing Device Outline 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 speed and large torque to rotate the shaft. Therefore, the upperstructure is swing. 1

TKAB-03-02-001 12-

Valve Unit Swing Motor

TOKAA90-EN-00

Swing Reduction Gear

T3-2-1

SECTION 3 COMPONENT OPERATION Group 2 Swing Device Swing Reduction Gear The swing reduction gear is a two-stage planetary reduction gear. Ring gears (8, 10) are installed to housing (5) and is fixed to the upperstructure. Shaft (1) in the swing motor rotates first stage sun gear (11), whose rotating torque is transmitted to second stage sun gear (7) through first stage planetary gears (2) and first stage carrier (9).

Second stage sun gear (7) rotates shaft (4) through second stage planetary gears (3) and second stage carrier (6). Shaft (4) is engaged with the internal gear of the swing bearing which is fixed to the undercarriage and swings the upperstructure.

10 9

7 6 4 5

TKAB-03-02-002 123-

Shaft of Swing Motor First Stage Planetary Gear Second Stage Planetary Gear

TOKAA90-EN-00

456-

Shaft Housing Second Stage Carrier

789-

T3-2-2

Second Stage Sun Gear Second Stage Ring Gear First Stage Sun Gear

10- First Stage Ring Gear 11- First Stage Sun Gear

SECTION 3 COMPONENT OPERATION Group 2 Swing Device 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 splined to rotor (12). 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.

1 2

4 5

11 3 10

8 TKAB-03-02-003 123-

Spring Brake Piston Plate

TOKAA90-EN-00

456-

Swing Parking Brake Selection Valve Friction Plate Plunger

78910-

T3-2-3

Retainer Shaft Swash Plate Shoe

11121314-

Housing Rotor Valve Plate Swing Parking Brake

SECTION 3 COMPONENT OPERATION Group 2 Swing Device Swing Parking Brake The parking brake is a spring set hydraulic released wettype multi-disc brake. When the brake release pressure is routed to brake piston chamber (6), the brake is released. The brake release pressure is supplied from the pilot pump only when either swing or front attachment is operated. In other cases (including engine stopping), brake piston chamber (6) is connected to the hydraulic oil tank, and the brake is automatically applied by springs (1).

When brake is released

When brake is applied

1. When the swing or front attachment control lever is operated, the swing parking brake release spool in the signal control valve is shifted. Therefore, pilot pressure from the pilot pump is supplied to port SH (5).

1. When the swing and front attachment control levers are returned to neutral, the swing parking brake release spool in the signal control valve is returned to neutral and pilot pressure supplied to port SH (5) is not supplied.

2. Pilot pressure supplied to port SH (5) opens check valve (4) and acts on brake piston chamber (6).

2. Therefore, check valve (4) is closed and the brake release pressure is released to the swing motor housing through orifice (3).

3. Consequently, as brake piston (2) is pushed up, plates (7) engaging on the outer circumference of rotor (9) and friction plates (8) engaging on the inner circumference of the motor housing are freed. Then, the brake is released.

TOKAA90-EN-00

T3-2-4

3. Consequently, the force of springs (1) act on plates (7) and friction plates (8) via brake piston (2). Consequently, the friction 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).

SECTION 3 COMPONENT OPERATION Group 2 Swing Device

1 2 3 9

TKAB-03-02-004

123-

Spring Brake Piston Orifice

TOKAA90-EN-00

45-

Check Valve Port SH (Brake Release Pressure)

678-

T3-2-5

Brake Piston Chamber Plate Friction Plate

9- Rotor 10- Swing Parking Brake Selection Valve

SECTION 3 COMPONENT OPERATION Group 2 Swing Device (Blank)

TOKAA90-EN-00

T3-2-6

SECTION 3 COMPONENT OPERATION Group 2 Swing Device Valve Unit The valve unit consists of make-up valves (2) and relief valves (1). Make-up valve (2) prevents cavitation in the circuit. Relief valve (1) prevents surge pressure in the circuit and protects the circuit from being overloaded.

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 tank circuit (port M (3)), poppet (5) is opened, hydraulic oil is drawn, and the lack of oil feed is compensated.

4 TKAB-03-02-005

TKAB-03-02-006

1 12-

Relief Valve Make-Up Valve

TOKAA90-EN-00

34-

Port M Control Valve

T3-2-7

Poppet

SECTION 3 COMPONENT OPERATION Group 2 Swing Device Relief Valve When starting or stopping swing operation, the swing circuit pressure becomes high. The relief valve prevents the circuit pressure from rising higher than the set pressure.  Low-Pressure Relief Operation (Shockless Function): 1. Pressure at port HP (swing circuit) acts on oil chamber C (9) through orifice (2) in poppet (1).

 High-Pressure Relief Operation (Overload Prevention): 1. After piston (6) reaches the stroke end, the circuit pressure becomes the normal relief set pressure.

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).

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. 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.

3. When pressure at port HP is decreased to the specified level, poppet (1) is closed by the spring (3) force.

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), and the force to push poppet (1) to the right appears. When this force is increased beyond the spring (3) force, poppet (1) is opened and pressure oil flows to port LP (tank circuit). 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.

TOKAA90-EN-00

T3-2-8

SECTION 3 COMPONENT OPERATION Group 2 Swing Device Initial Status (Piston (6) is in the right stroke end.)

LP 9

Movement of Piston (6)

Status that relief pressure is set to the set pressure

(Piston (6) is in the left stroke end.)

LP 9

7 TKAB-03-02-007

123-

Poppet Orifice Spring

TOKAA90-EN-00

456-

Passage A Passage B Piston

789-

T3-2-9

Oil Chamber B Oil Chamber A Oil Chamber C

SECTION 3 COMPONENT OPERATION Group 2 Swing Device (Blank)

TOKAA90-EN-00

T3-2-10

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Outline The control valve is the main control valve and swing control valve. The control valve controls the pressure, flow rate, and flow direction in the hydraulic circuit. The control valve consists of the main relief valve, overload relief valve, flow combiner valve, anti-drift valve, flow rate control valve, regenerative valve, boom lower meter-in cut valve, bypass shut-out valve, and spools. The spools are operated by pilot oil pressure.

Main Control Valve

Viewed the main control valve from the machine front side, the spools of the A side block are arranged as follows: travel (right) (1), bucket 1 (2), boom 1 (3), and arm 2 (4). Viewed from the machine front side, the spools of the B side block are arranged as follows: travel (left) (9), auxiliary (8), boom 2 (7), arm 1 (6), and bucket 2 (5). Viewed the swing control valve from the machine right side, the spools are arranged as follows: boom 3 (12), swing (13), bucket 3 (14), and arm 3 (15).

4 A

10 9 8 7 6 5

B TKAB-03-03-001

A-

4-Spool Side

B-

5-Spool Side

123-

Travel (Right) Bucket 1 Boom 1

456-

Arm 2 Bucket 2 Arm 1

789-

Boom 2 Auxiliary Travel (Left)

10- Main Relief Valve

Swing Control Valve

11 12 13 14 15 11- Main Relief Valve 12- Boom 3

TOKAA90-EN-00

13- Swing 14- Bucket 3

15- Arm 3

T3-3-1

TKAB-03-03-022

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve 1

11 53

51 50

47 46

45 43

44 42

17 18 19 20

41 40

22 23

39 36

24 25

26 g

31 b

29 a TKAB-03-03-002

TOKAA90-EN-00

T3-3-2

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve (4-Spool Side) Upper Surface

Right Side Surface 11

Lower Surface 12

13 14

5, 6, 17, 18, 19

abde-

4-Spool Side 5-Spool Side Travel (Right) Spool Bucket 1 Spool

fghj-

123-

Pump 1 Pump 2 Bypass Shut-Out Valve (5-Spool Side) Check Valve (Main Relief Circuit) Boom 1 Flow Rate Control Valve (Poppet Valve) Boom 1 Flow Rate Control Valve (Selector Valve) Flow Combiner Valve Check Valve (Flow Combiner Circuit) Line Filter Check Valve (Main Relief Circuit) Main Relief Valve Load Check Valve (Bucket Parallel Circuit) Bucket Regeneration Cut Valve Overload Relief Valve (Bucket: Rod Side)

15- Overload Relief Valve (Bucket: Bottom Side) 16- Bucket Regenerative Valve 17- Boom Lower Meter-In Cut Valve 18- Boom 1 Anti-Drift Valve (Selector Valve) 19- Boom 1 Anti-Drift Valve (Check Valve) 20- Load Check Valve 21- Overload Relief Valve (Boom 1: Bottom Side) 22- Overload Relief Valve (Low Pressure) (Boom 1: Rod Side) 23- Boom Overload Relief Selector Valve 24- Arm 2 Flow Rate Control Valve (Selector Valve) 25- Arm 2 Flow Rate Control Valve (Poppet Valve) 26- Check Valve (Arm Make-Up) 27- Arm Regeneration Cut Valve

4567891011121314-

TOKAA90-EN-00

Boom 1 Spool Arm 2 Spool Bucket 2 Spool Arm 1 Spool

24, 25

TKAB-03-03-003

k- Boom 2 Spool m- Auxiliary Spool n- Travel (Left) Spool

28- Check Valve 29- Bypass Shut-Out Valve (4-Spool Side) 30- Boom Regenerative Valve 31- Arm Regenerative Valve 32- Line Filter 36- Load Check Valve (Arm 1 Tandem Circuit) 38- Arm 1 Anti-Drift Valve (Selector Valve) 39- Overload Relief Valve (Arm 1: Bottom Side) 40- Arm 1 Anti-Drift Valve (Check Valve) 41- Overload Relief Valve (Arm 1: Rod Side) 42- Load Check Valve (Boom 2 Parallel Circuit) 43- Check Valve (Boom 2 Regenerative Circuit)

44- Boost Check Valve (Boom Regenerative Back Pressure Valve) 45- Overload Relief Valve (Boom 2: Rod Side) 46- Boom 2 Anti-Drift Valve (Selector Valve) 47- Boom 2 Anti-Drift Valve (Check Valve) 48- Load Check Valve (Auxiliary Parallel Circuit) 49- Load Check Valve (Auxiliary Tandem Circuit) 50- Overload Relief Valve (Auxiliary) 51- Overload Relief Valve (Auxiliary) 52- Load Check Valve (Travel (Left) Parallel Circuit) 53- Load Check Valve (Travel (Left) Tandem Circuit)

T3-3-3

Press Sensor (Arm Roll-In) Connecting Position Pressure Sensor (Bucket RollIn) Connecting Position

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve 1

11 53

51 50

47 46

45 43

44 42

17 18 19 20

41 40

22 23

39 36

24 25

26 g

31 b

29 a TKAB-03-03-002

TOKAA90-EN-00

T3-3-4

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve (5-Spool Side) Lower Surface

Left Side Surface

Upper Surface 3

3 53 50

49 43

46, 47

45 39

40, 38

36 TKAB-03-03-004

Pressure Sensor (Boom Lower) Connecting Position

Bypass Shut-Out Valve (5-Spool Side) Flow Combiner Valve Main Relief Valve Bucket Regenerative Valve Load Check Valve (Arm 1 Tandem Circuit) Arm 1 Anti-Drift Valve (Selector Valve)

711163638-

39- Overload Relief Valve (Arm 1: Bottom Side) 40- Arm 1 Anti-Drift Valve (Check Valve) 41- Overload Relief Valve (Arm 1: Rod Side) 43- Check Valve (Boom 2 Regenerative Circuit)

Upper Surface

44- Boost Check Valve (Boom Regenerative Back Pressure Valve) 45- Overload Relief Valve (Boom 2: Rod Side) 46- Boom 2 Anti-Drift Valve (Selector Valve) 47- Boom 2 Anti-Drift Valve (Check Valve)

Section A-A B

TKAB-03-03-024

A TKAB-03-03-023

TOKAA90-EN-00

49- Load Check Valve (Auxiliary Tandem Circuit) 50- Overload Relief Valve (Auxiliary) 51- Overload Relief Valve (Auxiliary) 52- Load Check Valve (Travel (Left) Parallel Circuit) 53- Load Check Valve (Travel (Left) Tandem Circuit)

T3-3-5

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve 1

11 53

51 50

47 46

45 43

44 42

17 18 19 20

41 40

22 23

39 36

24 25

26 g

31 b

29 a TKAB-03-03-002

TOKAA90-EN-00

T3-3-6

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Upper Surface B

A Section B-B

A TKAB-03-03-023

Arm 2 Spool

20- Load Check Valve 21- Overload Relief Valve (Boom 1: Bottom Side) 24- Arm 2 Flow Rate Control Valve (Selector Valve) 25- Arm 2 Flow Rate Control Valve (Poppet Valve)

Bucket 2 Spool

26- Check Valve (Arm Make-Up) 27- Arm Regeneration Cut Valve 29- Bypass Shut-Out Valve (4-Spool Side) 30- Boom Regenerative Valve 31- Arm Regenerative Valve

Section C-C 41

TKAB-03-03-025

31 Arm 1 Spool

36- Load Check Valve (Arm 1 Tandem Circuit) 38- Arm 1 Anti-Drift Valve (Selector Valve) 39- Overload Relief Valve (Arm 1: Bottom Side)

40- Arm 1 Anti-Drift Valve (Check Valve) 41- Overload Relief Valve (Arm 1: Rod Side)

Section D-D h

29 31

TOKAA90-EN-00

T3-3-7

TKAB-03-03-026

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve 1

11 53

51 50

47 46

45 43

44 42

17 18 19 20

41 40

22 23

39 36

24 25

26 g

31 b

29 a TKAB-03-03-002

TOKAA90-EN-00

T3-3-8

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Upper Surface B

Section E-E

17 43

TKAB-03-03-023 de-

Travel (Right) Spool Bucket 1 Spool

fk-

Boom 1 Flow Rate Control Valve (Poppet Valve) Load Check Valve (Bucket Parallel Circuit) Bucket Regeneration Cut Valve Overload Relief Valve (Bucket: Rod Side) Overload Relief Valve (Bucket: Bottom Side) Bucket Regenerative Valve

17- Boom Lower Meter-In Cut Valve 18- Boom 1 Anti-Drift Valve (Selector Valve) 19- Boom 1 Anti-Drift Valve (Check Valve) 22- Overload Relief Valve (Low Pressure) (Boom 1: Rod Side) 30- Boom Regenerative Valve 42- Load Check Valve (Boom 2 Parallel Circuit)

1213141516-

Boom 1 Spool Boom 2 Spool

TKAB-03-03-027 m- Auxiliary Spool n- Travel (Left) Spool

Section F-F 51

43- Check Valve (Boom 2 Regenerative Circuit) 44- Boost Check Valve (Boom Regenerative Back Pressure Valve) 45- Overload Relief Valve (Boom 2: Rod Side) 46- Boom 2 Anti-Drift Valve (Selector Valve) 47- Boom 2 Anti-Drift Valve (Check Valve)

Section G-G m

d 52

16 49

TOKAA90-EN-00

TKAB-03-03-028

T3-3-9

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Main Control Valve 1

11 53

51 50

47 46

45 43

44 42

17 18 19 20

41 40

22 23

39 36

24 25

26 g

31 b

29 a TKAB-03-03-002

TOKAA90-EN-00

T3-3-10

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Upper Surface

A Section H-H

3 B

TKAB-03-03-023

Bypass Shut-Out Valve (5-Spool Side)

47-

Check Valve (Main Relief Circuit) Flow Combiner Valve

Check Valve (Flow Combiner Circuit)

TKAB-03-03-029

10- Check Valve (Main Relief Circuit)

View J

Section K K

TKAB-03-03-030

TOKAA90-EN-00

T3-3-11

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Swing Control Valve

11 10 b

5 c

7 12

TKAB-03-03-031

Boom 3 Spool

Swing Spool

12345-

Main Relief Valve Load Check Valve (Boom 3) Load Check Valve (Swing) Load Check Valve (Bucket 3) Load Check Valve (Arm 3)

Load Check Valve (Arm 3 Parallel Circuit) Slow Return Valve (Arm 3) Make-Up Valve (Arm 3) Make-Up Valve (Arm 3)

10- Boom 3 Anti-Drift Valve (Selector Valve) 11- Boom 3 Anti-Drift Valve (Check Valve) 12- Main Pump 3

TOKAA90-EN-00

789-

T3-3-12

Bucket 3 Spool

Arm 3 Spool

SECTION 3 COMPONENT OPERATION Group 3 Control Valve

Section A-A 1 B

10, 11 B

T18J-03-03-031

T18J-03-03-032

Section B-B

Section C-C a

2 3

11 T18J-03-03-034 T18J-03-03-033

TOKAA90-EN-00

T3-3-13

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Swing Control Valve

11 10 b

5 c

9 d

7 12

TKAB-03-03-031

Boom 3 Spool

Swing Spool

12345-

Main Relief Valve Load Check Valve (Boom 3) Load Check Valve (Swing) Load Check Valve (Bucket 3) Load Check Valve (Arm 3)

Load Check Valve (Arm 3 Parallel Circuit) Slow Return Valve (Arm 3) Make-Up Valve (Arm 3) Make-Up Valve (Arm 3)

10- Boom Anti-Drift Valve (Selector Valve) 11- Boom Anti-Drift Valve (Check Valve) 12- Main Pump 3

TOKAA90-EN-00

789-

T3-3-14

Bucket 3 Spool

Arm 3 Spool

SECTION 3 COMPONENT OPERATION Group 3 Control Valve

Section D-D c B

4 1

10, 11 B

T18J-03-03-031

T18J-03-03-035

Section E-E

Section F-F d

8 T18J-03-03-037

T18J-03-03-036

TOKAA90-EN-00

T3-3-15

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Hydraulic Circuit Main Circuit Pressure oil from main pump 1 (31) flows to travel (right) spool (6), bucket 1 spool (7), boom 1 spool (9), and arm 2 spool (12) at 4-spool side (A) of main control valve (4). Pressure oil from main pump 2 (29) flows to bucket 2 spool (17), arm 1 spool (18), boom 2 spool (19), auxiliary spool (33), and travel (left) spool (34) at 5-spool side (B) of main control valve (4). Pressure oil from main pump 3 (30) flows to boom 3 spool (27), swing spool (26), bucket 3 spool (25), and arm 3 spool (23) of swing control valve (22). Parallel circuits (13, 16, 37) are provided in each main circuit (between the main pumps and the actuators), and make the combined operation possible. The boom flow combiner circuit (14) and arm flow combiner circuit (15) are provided in the main control valve for the boom and arm circuits. Then, pressure oil from main pump 1 (31) is combined with pressure oil from main pump 2 (29) when performing a single operation.

fNOTE: Pressure oil from main pump 1 (31) and main

pump 2 (29) is combined with pressure oil from main pump 3 (30) in the external piping of the main control valve.

Main relief valves (5, 28) are provided in the main circuits (between the main pumps and the actuators). Main relief valves (5, 28) prevent 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 (8, 10, 20, 21, 32) are provided in the actuator circuits (between the control valve and the actuator) of boom, arm, bucket, and auxiliary. Overload relief valves (8, 10, 20, 21, 32) prevent surge pressure caused by external force in the actuator circuit from exceeding the set pressure when the spool is in neutral (with the control lever set in neutral). The boom overload relief selector valve (11) is provided in the boom lower circuit of boom 1 spool (9). The boom overload relief selector valve (11) decreases the relief set pressure in the boom lower circuit, and reduces machine vibration when performing digging and leveling operation (boom lower operation).

TOKAA90-EN-00

T3-3-16

SECTION 3 COMPONENT OPERATION Group 3 Control Valve

36 35

B 17 18 19

1 21

33 32

TKAB-03-03-005 A-

Main Control Valve (4-Spool Side)

B-

12345678910-

Boom Cylinder Swing Motor Travel Motor Main Control Valve Main Relief Valve Travel (Right) Spool Bucket 1 Spool Overload Relief Valve Boom 1 Spool Overload Relief Valve

11- Boom Overload Relief Selector Valve 12- Arm 2 Spool 13- Parallel Circuit (4-Spool Side) 14- Boom Flow Combiner Circuit 15- Arm Flow Combiner Circuit 16- Parallel Circuit (5-Spool Side) 17- Bucket 2 Spool 18- Arm 1 Spool 19- Boom 2 Spool 20- Overload Relief Valve

TOKAA90-EN-00

Main Control Valve (5-Spool Side) 2122232425262728293031-

T3-3-17

Overload Relief Valve Swing Control Valve Arm 3 Spool Make-Up Valve Bucket 3 Spool Swing Spool Boom 3 Spool Main Relief Valve Main Pump 2 Main Pump 3 Main Pump 1

323334353637-

Overload Relief Valve Auxiliary Spool Travel (Left) Spool Arm Cylinder Bucket Cylinder Parallel Circuit

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Pilot Operation Control Circuit Pressure oil (indicated with numbers) from the pilot valve acts on the spools in the control valve and moves the spools. Air bleed circuit (a) is located in the upper of control valve and bleeds air automatically.

TOKAA90-EN-00

T3-3-18

SECTION 3 COMPONENT OPERATION Group 3 Control Valve a 11

8 a

3 TKAB-03-03-006

Air Bleed Circuit

1234-

Boom Raise Boom Lower Arm Roll-Out Arm Roll-In

TOKAA90-EN-00

5678-

Swing (Left) Swing (Right) Bucket Roll-In Bucket Roll-Out

9101112-

T3-3-19

Travel Left Forward Travel Left Reverse Travel Right Forward Travel Right Reverse

13- Auxiliary 14- Auxiliary

SECTION 3 COMPONENT OPERATION Group 3 Control Valve External Pilot Pressure Circuit  The bypass shut-out valve (4-spool side) (7) is shifted by pilot pressure (d) from the 4-spool solenoid valve unit (SG).  The boom overload relief selector valve (6) is shifted by pilot pressure (b) from the 4-spool solenoid valve unit (SI).  Pressure in main relief valve (2) is increased by pilot pressure (a) from the 4-spool solenoid valve unit (SF).  The bypass shut-out valve (5-spool side) (14) is shifted by pilot pressure (f ) from the 2-spool solenoid valve unit (SC).  The arm 2 flow rate control valve (8) is shifted by pilot pressure (c) from the 2-spool solenoid valve unit (SI).

TOKAA90-EN-00

T3-3-20

 Flow combiner valve (1) is shifted by pilot pressure (g) from the flow combiner valve control spool in the signal control valve.  When performing arm roll-in operation, arm 1 spool (11) is shifted. Then, pilot pressure (e) from the pilot pump acts on the arm 1 anti-drift valve (12) and releases lock of the arm 1 anti-drift valve (12).  When performing boom lower operation, boom 1 spool (3) is shifted. Then, pilot pressure (e) from the pilot pump acts the boom 1 anti-drift valve (4) and the boom 2 anti-drift valve (13) and releases the lock of the boom 1 anti-drift valve (4) and boom 2 antidrift valve (13). At the same time, the boom lower pilot pressure (h) acts on the boom 3 anti-drift valve (16) and releases the lock of the boom 3 anti-drift valve (16).

SECTION 3 COMPONENT OPERATION Group 3 Control Valve 1

6 b c

16 h ab-

Pilot Pressure from 4-Spool Solenoid Valve Unit (SF) Pilot Pressure from 4-Spool Solenoid Valve Unit (SI)

cde-

1234-

Flow Combiner Valve Main Relief Valve Boom 1 Spool Boom 1 Anti-Drift Valve

TOKAA90-EN-00

56-

Pilot Pressure from 2-Spool Solenoid Valve Unit (SI) Pilot Pressure from 4-Spool Solenoid Valve Unit (SG) Pilot Pressure from Pilot Pump

Overload Relief Valve (Low Pressure) (Boom 1: Rod Side) Boom Overload Relief Selector Valve

Pilot Pressure from 2-Spool Solenoid Valve Unit (SC)

hBypass Shut-Out Valve (4-Spool Side) 8- Arm 2 Flow Rate Control Valve 11- Arm 1 Spool 12- Arm 1 Anti-Drift Valve

T3-3-21

TKAB-03-03-007 Pilot Pressure from Flow Combiner Valve Control Spool in Signal Control Valve Boom Lower Pilot Pressure from Pilot Valve

13- Boom 2 Anti-Drift Valve 14- Bypass Shut-Out Valve (5-Spool Side) 15- Boom 3 Spool 16- Boom 3 Anti-Drift Valve

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Flow Combiner Valve The flow combiner valve prevents the machine from mistracking when pressure oil is not equally supplied to both right and left travel motors during combined operation of travel and front attachment.

fNOTE: As an example, the combined operation of travel

and boom raise is explained here.

Operation

1. When performing combined operation boom raise and travel, pilot pressure shifts travel (right) spool (5), travel (left) spool (4), boom 1 spool (7), boom 2 spool (11), and boom 3 spool (13).

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 (b) from the pilot pump flows through the flow combiner valve control spool and acts on spool (1) in the flow combiner valve. 4. When the force generated by pilot pressure (b) from the flow combiner valve control spool increases over the spring (2) force, spool (1) compresses spring (2) and moves down. 5. Pressure oil (a) from pump 1 (10) flows to travel (right) spool (5) and travel (left) spool (4) through spool (1).

TKAB-03-03-008

6. Pressure oil from pump 2 (9) flows to boom cylinder (8) through boom 2 spool (11) and moves the boom at this time. A part of pressure oil from pump 2 (9) also flows to travel (left) spool (4) through the parallel circuit.

ab-

Pressure Oil from Pump 1 (10) Pilot Pressure from Flow Combiner Valve Control Spool

cd-

To Travel (Left) Spool (4) To Hydraulic Oil Tank

Spool (Flow Combiner Valve)

Spring

7. Consequently, pressure oil from pump 1 (10) and a part of pressure oil from pump 2 (9) is equally supplied to both travel motor (left) (3) and travel motor (right) (6). Then, the machine can travel straight. As a part of pressure oil from pump 2 (9) and pressure oil from pump 3 (12) flows to boom cylinder (8), combined operation becomes possible.

TOKAA90-EN-00

T3-3-22

SECTION 3 COMPONENT OPERATION Group 3 Control Valve

15 6 5

7 8

1 a b

2 c

10 9 3

TKAB-03-03-009 a-

Pressure Oil from Pump 1 (10)

Pilot Pressure from Flow Combiner Valve Control Spool

To Travel (Left) Spool (4)

1234-

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

5678-

Travel (Right) Spool Travel Motor (Right) Boom 1 Spool Boom Cylinder

9101112-

Pump 2 Pump 1 Boom 2 Spool Pump 3

TOKAA90-EN-00

T3-3-23

13- Boom 3 Spool 14- Swing Control Valve 15- Main Control Valve

SECTION 3 COMPONENT OPERATION Group 3 Control Valve 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 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 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).

TOKAA90-EN-00

T3-3-24

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Normal Operation: 2

LP 10

5 TKAB-03-03-010

When Performing Relief Operation: 2

5 TKAB-03-03-011

HP- Main Circuit

LP- Hydraulic Oil Tank

123-

456-

Main Poppet Orifice A Orifice B

TOKAA90-EN-00

Seat Passage A Spring B

789-

T3-3-25

Piston Pilot Poppet Spring A

10- Spring Chamber 11- Sleeve

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Pressure Increasing Operation 1. When pilot pressure from the 4-spool solenoid valve unit (SF) acts on port PF, spring B (6) is compressed by piston (7). 2. The force of spring B (6) becomes strong. 3. As pressure required in order to open pilot poppet (8) is increased, the relief set pressure is increased.

TOKAA90-EN-00

T3-3-26

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Pressure Increasing Operation: 8

TKAB-03-03-012 HP- Main Circuit LP- Hydraulic Oil Tank

PF- Pilot Pressure from 4-Spool Solenoid Valve Unit (SF)

Spring B

TOKAA90-EN-00

Piston

T3-3-27

Pilot Poppet

SECTION 3 COMPONENT OPERATION Group 3 Control Valve 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 1. Pressure in port HP (actuator circuit) 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 main poppet (2), 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 (1). 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).

TOKAA90-EN-00

T3-3-28

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Normal Operation: 1

LP 4

9 TKAB-03-03-013

When Performing Relief Operation: 1

9 TKAB-03-03-014

HP- Actuator Circuit

LP- Hydraulic Oil Tank

123-

456-

Orifice Main Poppet Sleeve

TOKAA90-EN-00

Spring A Passage A Spring B

789-

T3-3-29

Spring C Pilot Poppet Spring Chamber

10- Piston

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Make-Up Operation 1. When pressure in port HP (actuator circuit) decreases lower than pressure in port LP (hydraulic oil tank), main poppet (2) 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, main poppet (2) is closed by the force of spring C (7).

TOKAA90-EN-00

T3-3-30

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Make-Up Operation: 7

LP TKAB-03-03-015

HP- Actuator Circuit

LP- Hydraulic Oil Tank

Main Poppet

TOKAA90-EN-00

Spring C

T3-3-31

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Overload Relief Valve (Low Pressure) Operation

The overload relief valve (low pressure) is provided in the boom lower circuit. The overload relief valve (low pressure) is shifted by pilot pressure from the 4-spool solenoid valve unit (SI), and relieves the boom cylinder rod side circuit at the low pressure. Therefore, machine vibration is reduced when performing boom lower operation.

1. When pilot pressure does not act on piston (1) (When performing normal operation), pressure oil which flows to the boom cylinder rod side from port HP flows to chamber c (7) through piston (9). Pressure oil acts on main poppet (8) and main poppet (8) is kept closed. At this time, hydraulic oil is held in chamber a (3) and chamber b (5). Therefore, even if pressure at port HP increases, pilot poppet (6) is not opened.

fNOTE: Two overload relief valves are provided in the

boom lower circuit. The set relief pressure of the overload relief valve (low pressure) is lower than that of another overload relief valve.

2. When pilot pressure from the 4-spool solenoid valve unit (SI) acts on piston (1), poppet (2) is opened by piston (1). When poppet (2) is opened, chamber a (3) and chamber b (5) are connected to port LP (hydraulic oil tank) along the external circumference of sleeve (10). (Refer to SYSTEM/Control System/T22-66.) 3. When the force generated by pressure in chamber c (7) reaches the set pressure of spring (4), pilot poppet (6) is opened. When pilot poppet (6) is opened, pressure in chamber c (7) decreases. 4. A pressure difference is developed between the front and rear of the orifice in piston (9). Then, main poppet (8) and piston (6) are moved to the left due to this pressure difference. As main poppet (8) is opened, pressure oil flows to port LP from port HP. 5. As the set operating pressure is low and holding pressure at the boom cylinder rod side decreases, machine vibration is reduced when performing boom lower operation.

When Performing Normal Operation: 1

10 TKAB-03-03-016 HP- Actuator Circuit LP- Hydraulic Oil Tank

SD- Pilot Pressure from 4-Spool Solenoid Valve Unit (SI)

123-

456-

Piston Poppet Chamber a

TOKAA90-EN-00

Spring Chamber b Pilot Poppet

789-

T3-3-32

Chamber c Main Poppet Piston

10- Sleeve

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Relief Operation: 1

LP 10

5 TKAB-03-03-017

LP 5 TKAB-03-03-018

TOKAA90-EN-00

T3-3-33

SECTION 3 COMPONENT OPERATION Group 3 Control Valve 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. Boom Regenerative Valve Operation 1. When performing boom lower operation, returning oil from the boom 1 spool and boom 3 spool is restricted.

4. Returning oil from boom cylinder (2) bottom side is supplied to the rod side and the regenerative operation is done.

2. When performing boom lower operation, returning oil from boom cylinder (2) bottom side acts on check valve (4) through hole (5) of boom 2 spool (3).

5. When boom cylinder (2) reaches the stroke end or digging loads increase, pressure in boom cylinder (2) rod side circuit is higher than the bottom side. Check valve (4) of the boom regenerative valve is closed and regenerative operation is stopped.

3. When pressure in boom cylinder (2) rod side is lower than the bottom side, check valve (4) is opened.

b b a bb 2 3

TKAB-03-03-019

Pilot Pump Pressure

To Main Control Valve (5-Spool Side)

Boom Cylinder

Boom 2 Spool

TOKAA90-EN-00

T3-3-34

Check Valve (Boom Regenerative Valve)

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Boom Regenerative Operation:

TJBA-03-03-007

Returning Oil from Boom Cylinder (2) Bottom Side

Pressure Oil to Boom Cylinder (2) Rod Side

Boom Cylinder

Boom 3 Spool

TOKAA90-EN-00

T3-3-35

Check Valve

Hole

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Bucket Regenerative Valve, Arm Regenerative Valve The regenerative valves supply returning oil of the cylinder rod side to the bottom side, prevent cylinder hesitation, and increase bucket or arm roll-in operating speed when performing bucket or arm roll-in operation.

fNOTE: The bucket regenerative valve is explained here. Operation (when performing Bucket Regenerative Operation)

1. When performing bucket roll-in operation, the return circuits are provided in bucket 1 spool (3) and the bucket 2 spool. However, the return circuit is not provided in the bucket 3 spool. Consequently, returning oil is restricted in the bucket roll-in circuit.

2. Returning oil from bucket cylinder (1) rod side flows to and acts on bucket regenerative valve (2) through hole (4) of bucket 1 spool (3) when performing bucket roll-in operation. 3

3. At this time, when pressure in bucket cylinder (1) bottom side is lower than the rod side, bucket regenerative valve (2) is opened.

T450-03-03-043

4. Consequently, returning oil from 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 bucket cylinder (1) bottom side and regenerative operation is done.

Pressure Oil from Pump 1

12-

Bucket Cylinder Bucket Regenerative Valve

5. Therefore, cylinder hesitation is prevented and bucket roll-in operating speed increases during bucket roll-in operation.

TOKAA90-EN-00

T3-3-36

Bucket 1 Spool

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Bucket Regenerative Operation:

4 1

T450-03-03-044 1-

Bucket Cylinder

TOKAA90-EN-00

Bucket Regenerative Valve

T3-3-37

Bucket 1 Spool

Hole

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Operation (when performing Bucket Regenerative Cut Operation) 3

1. When bucket cylinder (3) reaches the stroke end or digging loads increase when performing bucket roll-in operation, pressure in bucket cylinder (3) bottom side increases. At this time, pressure oil from the pump 1 acts on piston (7) of the bucket regeneration cut valve (1).

2. Piston (7) compresses spring (2) and moves up (to the left in the circuit diagram).

3. Pressure in bucket cylinder (3) rod side is lower than bucket cylinder (3) bottom side. As bucket regenerative valve (4) is kept closed and pressure oil from bucket cylinder (3) rod side does not flow to bucket cylinder (3) bottom side, regenerative operation is not done.

4. Pressure oil from bucket cylinder (3) rod side flows to the hydraulic oil tank through bucket spool (5) and the external circumference of plunger (6). 5. Therefore, pressure in bucket cylinder (3) rod side decreases and digging force is improved.

TOKAA90-EN-00

a T450-03-03-039

Pressure Oil from Pump 1

To Hydraulic Oil Tank

Bucket Regeneration Cut Valve Spring Bucket Cylinder Bucket Regenerative Valve

56-

Bucket Spool Plunger (Bucket Regeneration Cut Valve) Piston (Bucket Regeneration Cut Valve)

234-

T3-3-38

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Bucket Regeneration Cut Operation:

4 3

2 6 b c 7

T450-03-03-045

ab-

Pressure Oil from Pump 1 To Hydraulic Oil Tank

Returning Oil from Bucket Cylinder Rod Side

Pressure Oil to Bucket Cylinder Bottom Side

123-

Bucket Regeneration Cut Valve Spring Bucket Cylinder

45-

Bucket Regenerative Valve Bucket Spool

Plunger (Bucket Regeneration Cut Valve)

TOKAA90-EN-00

T3-3-39

Piston (Bucket Regeneration Cut Valve)

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Flow Rate Control Valve The flow rate control valves are provided in the arm 2 and boom 1 circuits, restricts oil flow rate in the circuit when performing combined operation, and gives priority to other actuators. Each flow rate control valve is operated when performing combined operation as shown below. Flow Rate Combined Operation Control Valve Arm 2 Boom Raise, Arm Roll-In Boom 1 Boom Lower (Operation with the front attachment above ground (high pressure at bottom side)) Operation 1. Generally, pressure oil (a) from the main pump 1 flows to the actuator through the hole of poppet valve (3) in the flow rate control valve and the spool in the control valve. (b) 2. A part of pressure oil (a) from the main pump 1 opens check valve (5) through the passage as illustrated and acts on selector valve (2). However, pressure oil is blocked by selector valve (2). 3. On the other hand, MC (main controller) outputs pilot pressure (c) for the flow rate control when performing combined operation of front attachment. 4. Selector valve (2) is moved to the left by pilot pressure (c). Pressure oil (a), which from the main pump 1 is blocked by selector valve (2), acts on piston (6). 5. When piston (6) moves down, poppet valve (3) is pushed down. As apart of the hole is closed, flow rate of pressure oil (b) which flows to the actuator through the spool is restricted. 6. Therefore, as pressure oil (a) from the main pump 1 preferentially flows to other cylinders, the combined operation can be smoothly performed.

TOKAA90-EN-00

T3-3-40

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Flow Rate Control OFF:

Section A

5 6 3 4

TKAB-03-03-038

Flow Rate Control ON:

Section A

5 6 3

TKAB-03-03-039

ab-

Pressure Oil from Main Pump 1 To Actuator through Spool

Pilot Pressure for Flow Rate Control

23-

Selector Valve Poppet Valve

45-

Check Valve Check Valve

TOKAA90-EN-00

T3-3-41

Piston

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Operation of Arm 2 Flow Rate Control Valve 1. The boom raise pilot pressure (c) acts on boom 1 spool (7) and the arm roll-in pilot pressure (e) acts on arm 2 spool (4) respectively when performing the combined operation of boom raise and arm rollin. 2. Pressure oil (b) from main pump 1 is blocked by boom 1 spool (7). 3. Pressure oil from bypass circuit (a) flows to boom 1 spool (7) through the boom 1 flow rate control valve (poppet valve) (8). Pressure oil flows to boom cylinder (1) bottom side and the boom is raised. 4. Pressure oil from bypass circuit (a) flows to arm 2 spool (4) through the arm 2 flow rate control valve (poppet valve) (5). Pressure oil flows to arm cylinder (2) bottom side and the arm is rolled in. 5. According to the signal of MC (Main controller), pilot pressure (d) for the arm 2 flow rate control flows from the 2-spool solenoid valve unit (SI) to the arm 2 flow rate control valve (selector valve) (6) when performing combined operation of boom raise and arm roll-in. 6. Selector valve (6) of the arm 2 flow rate control valve is moved to the left by pilot pressure (d) for the flow rate control as illustrated. Pressure oil from bypass circuit (a) acts on the bottom of the arm 2 flow rate control valve (poppet valve) (5). 7. Therefore, as pressure oil which flows from bypass circuit (a) to arm 2 spool (4) is restricted, flow rate of pressure oil which flows to boom 1 spool (7) increases and the boom is given priority to operate. 8. As pressure oil, which flows from the main pump 3 to the swing control valve, is restricted in the circuit to the arm 3 spool, the boom is given priority to operate. 9. Pressure oil which flows from the main pump 2 to the main control valve flows to both the arm 1 spool and the boom 2 spool. 10. The boom raise operation is given priority to over the arm roll-in operation according to flow rate of pressure oil of the main pumps 1 to 3. Therefore, the combined operation can be smoothly performed.

TOKAA90-EN-00

T3-3-42

SECTION 3 COMPONENT OPERATION Group 3 Control Valve

9 8

7 d

6 5

e 2

TKAB-03-03-033

ab-

Bypass Circuit Pressure Oil from Main Pump 1

Boom Raise Pilot Pressure

Pilot Pressure for Arm 2 Flow Rate Control

Arm Roll-In Pilot Pressure

123-

Boom Cylinder Arm Cylinder Main Control Valve (4-Spool Side)

45-

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

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

Boom 1 Flow Rate Control Valve (Poppet Valve) Boom 1 Flow Rate Control Valve (Selector Valve)

TOKAA90-EN-00

T3-3-43

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Boom Lower Meter-In Cut Valve The boom lower meter-in cut valve is provided in the boom lower circuit. The boom lowers due to own weight by the regenerative circuit of boom 2 spool (2) and allows pressure oil from the main pumps to other actuator. Consequently, operating speeds of other actuators increase. (Refer to SYSTEM/Hydraulic System/T2-4-28.) Operation (Boom Lower with Front Attachment above Ground) 1. Boom lower pilot pressure (b) acts on boom 1 spool (6), boom 2 spool (2), boom 3 spool (16), and port 4Pc11 (12) when lowering the boom.

5. On the other hand, pressure oil from boom cylinder (1) bottom side also flows to boom 2 spool (2) through the boom flow combiner circuit (19). Pressure oil is supplied to boom cylinder (1) rod side through the boom regenerative valve in boom 2 spool (2). Pressure oil flowing to boom 3 spool (16) returns to the hydraulic oil tank through the orifice.

2. A part of pressure oil (c) from boom cylinder (1) bottom side flows through orifice (8) and piston (7), and acts on the spool (boom lower meter-in cut valve) (4). When the force generated by pressure from boom cylinder (1) bottom side exceeds spring (9) force, spool (4) compresses spring (9) and moves to the left (to the right in the circuit diagram).

6. Therefore, the boom lowers due to own weight and the boom is lowered. 7. Consequently, when performing combined operation of boom lower and other actuators, more pressure oil is supplied to other actuators and speeds of actuators increase.

3. Boom lower pilot pressure (b) from port 4Pc11 (12) flows to spool (4) through the boom 1 flow rate control valve (selector valve) (3) through spool (4). (a) 4. Therefore, the boom 1 flow rate control valve (selector valve) (3) is shifted and pressure oil which flows from pump 1 (11) to boom 1 spool (6) is restricted. (Refer to Flow Rate Control Valve on T3-340.)

To Boom 1 Flow Rate Control Valve (Selector Valve)

Boom Lower Pilot Pressure

123-

Boom Cylinder Boom 2 Spool Boom 1 Flow Rate Control Valve (Selector Valve) Spool (Boom Lower Meter-In Cut Valve)

Boom 1 Flow Rate Control Valve (Poppet Valve) Boom 1 Spool Piston Orifice Spring

10111214-

TOKAA90-EN-00

6789-

Pressure Oil from Boom Cylinder (1) Bottom Side

Pump 2 Pump 1 Port 4Pc11 Bypass Shut-Out Valve (4-Spool Side) 15- Pump 3

T3-3-44

8 TJAA-03-03-005 d-

To Hydraulic Oil Tank

16171819-

Boom 3 Spool Swing Control Valve Main Control Valve Boom Flow Combiner Circuit

SECTION 3 COMPONENT OPERATION Group 3 Control Valve When Performing Boom Lower with Front Attachment above Ground: 18

11 10 2 b 15

17 16

TKAB-03-03-020

TOKAA90-EN-00

T3-3-45

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Operation (With Track off Ground) 1. The operation which raising the track off the ground is the boom lower operation. (Boom cylinder (1) is retracted.) As pressure at boom cylinder (1) bottom side decreases, pressure which acts on spool (4) also decreases. 2. When pressure from boom cylinder (1) bottom side is smaller than spring (9) force, spool (4) is moved to the right (to the left in the circuit diagram) by spring (9) force. 3. As the boom lower pilot pressure (b) does not act on the boom 1 flow rate control valve (selector valve) (3), the boom 1 flow rate control valve (poppet valve) (5) is opened. 4. Pressure oil from pump 1 (11) flows to boom cylinder (1) rod side through boom 1 spool (6). Therefore, the jack-up force increases. (Pressure oil which flows from pump 2 (10) to boom 2 spool (2) and pressure oil which flows from pump 3 (15) to boom 3 spool (16) respectively returns to the hydraulic oil tank through neutral circuit (20).) 5. Therefore, boom lower meter-in cut control is not operated with the track raised off the ground. In addition, the control to close bypass shut-out valve (14) is also operated. (Refer to SYSTEM/Hydraulic System/T2-4-30.)

ab1234-

To Boom 1 Flow Rate Control Valve (Selector Valve) Boom Lower Pilot Pressure

Boom Cylinder Boom 2 Spool Boom 1 Flow Rate Control Valve (Selector Valve) Spool (Boom Lower Meter-In Cut Valve)

TOKAA90-EN-00

6789-

Pressure Oil from Boom Cylinder (1) Bottom Side To Hydraulic Oil Tank

Boom 1 Flow Rate Control Valve (Poppet Valve) Boom 1 Spool Piston Orifice Spring

10111214-

8 TJAA-03-03-005

Pilot Pressure from 4-Spool Solenoid Valve Unit (SG)

Pump 2 Pump 1 Port 4Pc11 Bypass Shut-Out Valve (4-Spool Side) 15- Pump 3

T3-3-46

1617181920-

Boom 3 Spool Swing Control Valve Main Control Valve Boom Flow Combiner Circuit Neutral Circuit

SECTION 3 COMPONENT OPERATION Group 3 Control Valve With Track off Ground: 18

4 12

11 10 20

b 15

17 16

TKAB-03-03-034

TOKAA90-EN-00

T3-3-47

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Anti-Drift Valve Holding Operation

The anti-drift valves are provided in the circuits of the boom cylinder bottom side and arm cylinder rod side, and reduces the cylinder drift.

1. As pressure oil from pilot pump (a) is blocked by arm 1 spool (4) with the control lever set in neutral (the spool in neutral), the anti-drift valve (3) (selector valve) is not shifted.

fNOTE: The arm 1 anti-drift valve is explained here.

2. Returning oil from arm cylinder (1) rod side (d) flows through orifice (7) of anti-drift valve (check valve) (2) and acts on spring (5) chamber and spring (6) chamber of anti-drift valve (selector valve) (3). However, returning oil from arm cylinder (1) rod side (d) is blocked by anti-drift valve (selector valve) (3). 3. Consequently, as anti-drift valve (check valve) (2) is pushed and the returning oil from arm cylinder (1) rod side (d) is blocked, arm cylinder (1) drift is reduced.

Pressure Oil from Pilot Pump

Returning Oil from Arm Cylinder (1) Rod Side

12-

Arm Cylinder Anti-Drift Valve (Check Valve)

34-

Anti-Drift Valve (Selector Valve) Arm 1 Spool

TOKAA90-EN-00

T3-3-48

TKAB-03-03-037

SECTION 3 COMPONENT OPERATION Group 3 Control Valve

2 7 a

4 TJAA-03-03-021 a-

Pressure Oil from Pilot Pump

Returning Oil from Arm Cylinder (1) Rod Side

23-

Anti-Drift Valve (Check Valve) Anti-Drift Valve (Selector Valve)

45-

Arm 1 Spool Spring

TOKAA90-EN-00

67-

T3-3-49

Spring Orifice

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Releasing Operation 1. Pressure oil from pilot pump (c) pushes piston (8) of the anti-drift valve and shifts anti-drift valve (selector valve) (3) when performing arm roll-in operation. 2. Pressure oil in spring (5) chamber of anti-drift valve (check valve) (2) is returned to the hydraulic oil tank through the passage of anti-drift valve (selector valve) (3). (b) 3. When pressure in spring (5) chamber decreases, and pressure in spring (5) chamber and spring (5) force is lower than pressure of returning oil from arm cylinder (1) rod side (d), anti-drift valve (check valve) (2) moves up (to the right in the circuit diagram). 4. Consequently, returning oil from arm cylinder (1) rod side (d) flows to the hydraulic oil tank.

fNOTE: Orifice (7) of anti-drift valve (check valve)

(2) decreases pressure in spring (5) chamber slowly. Therefore, anti-drift valve (check valve) (2) is prevented from moving quickly and shock when performing arm roll-in or operation is reduced. 1

c d

b TKAB-03-03-040

ab-

Pressure Oil from Pump 1 To Hydraulic Oil Tank

Pressure Oil from Pilot Pump

12-

Arm Cylinder Anti-Drift Valve (Check Valve)

34-

Anti-Drift Valve (Selector Valve) Arm 1 Spool

TOKAA90-EN-00

T3-3-50

Returning Oil from Arm Cylinder (1) Rod Side

SECTION 3 COMPONENT OPERATION Group 3 Control Valve 8

2 7

TJAA-03-03-022 bc-

To Hydraulic Oil Tank Pressure Oil from Pilot Pump

Returning Oil from Arm Cylinder (1) Rod Side

23-

Anti-Drift Valve (Check Valve) Anti-Drift Valve (Selector Valve)

45-

Arm 1 Spool Spring

TOKAA90-EN-00

67-

T3-3-51

Spring Orifice

Piston

SECTION 3 COMPONENT OPERATION Group 3 Control Valve Bypass Shut-Out Valve Operation

Bypass shut-out valves (3, 7) are provided in the downstream of the neutral circuits in 4-spool side (1) and 5-spool side (5) in the main control valve. Bypass shut-out valves (3, 7) block the neutral circuits (the return circuits to the hydraulic oil tank) in 4-spool side (1) and 5-spool side (5), increase oil flow rate which flows to the cylinder, and increase the cylinder operating speed.

1. According to the signal of MC (main controller), pilot pressure (f ) outputs from the 4-spool solenoid valve unit (SG), when raising the track off the ground and shifts the bypass shut-out valve (4-spool side) (3). 2. As the neutral circuit of main control valve (4-spool side) (1) is blocked, pressure oil from pump 1 (6) flows to boom 1 spool (2) and is supplied to the boom cylinder (4) bottom side.

fNOTE: The bypass shut-out valve (4-spool side) (3) is explained here.

3. Consequently, the track is raised off the ground faster. (Refer to Boom Lower Meter-In Cut Valve on T3-3-46.)

TOKAA90-EN-00

Pilot Pressure from 4-Spool Solenoid Valve Unit (SG)

Bypass Shut-Out Valve (4-Spool Side)

T3-3-52

T450-03-03-050 bc-

Neutral Circuit (Pump 1 (6)) To Hydraulic Oil Tank

SECTION 3 COMPONENT OPERATION Group 3 Control Valve With Track off Ground: 1

TKAB-03-03-034

Pilot Pressure from 4-Spool Solenoid Valve Unit (SG)

Main Control Valve (4-Spool Side) Boom 1 Spool

TOKAA90-EN-00

34-

Bypass Shut-Out Valve (4-Spool Side) Boom Cylinder

56-

T3-3-53

Main Control Valve (5-Spool Side) Pump 1

Bypass Shut-Out Valve (5-Spool Side)

SECTION 3 COMPONENT OPERATION Group 3 Control Valve (Blank)

TOKAA90-EN-00

T3-3-54

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Outline The pilot valve controls pilot pressure oil in order to move the spool in the control valves. 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. The 2-port pilot valves are for bucket open/close (only loading shovel).  Front Attachment/Swing Pilot Valve

Right

Left

Port No. 1 2 3 4 1 2 3 4

ISO Control Pattern

Hitachi Pattern

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

    Arm Roll-In Swing (Right) Arm Roll- Out Swing (Left)

Hydraulic Symbol

TKAB-03-04-010

2 P-

TOKAA90-EN-00

T3-4-1

Port P (Pressure Oil from Pilot Pump)

T-

TDC1-03-04-001

Port T (To Hydraulic Oil Tank)

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve  Travel Pilot Valve Port No. 1 2 3 4

Travel (Right Reverse) Travel (Right Forward) Travel (Left Forward) Travel (Left Reverse) P

Hydraulic Symbol

TPPP-03-04-003

2 3

4 TKAB-03-04-010

1 TPPP-03-04-004

 Bucket Open/Close Pilot Valve (Only Loading Shovel) Port No. 1 2

Auxiliary

P-

Port P (Pressure Oil from Pilot Pump)

T-

Port T (To Hydraulic Oil Tank)

Close Open

Hydraulic Symbol T

P 1

TKAB-03-04-011

1 P-

TOKAA90-EN-00

T3-4-2

Port P (Pressure Oil from Pilot Pump)

2 T-

TDAA-03-04-006

Port T (To Hydraulic Oil Tank)

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Operation (Front Attachment/Swing and Travel Pilot Valves)

Front Attachment/ Swing Pilot Valve 1

The spool (7) head is hanged from the upper surface of spring guide (4). Spring guide (4) is kept raised by return spring (6). 2

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).

3 4 5 6 E

7 8

TDC1-03-04-002

Travel Pilot Valve 1

2 3 4 5 6

7 8

TPPP-03-04-010 12-

Cam Pusher

TOKAA90-EN-00

34-

Casing Spring Guide

56-

T3-4-3

Balance Spring Return Spring

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve 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).

T523-02-05-001 a-

5. This status continues until hole (8) on spool (7) is connected to port P.

TOKAA90-EN-00

T3-4-4

Pilot Pressure

Control Lever Stroke

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Front Attachment/ Swing Pilot Valve 1

7 T

8 P a

a TPPP-03-04-015

TPPP-03-04-006

Travel Pilot Valve 1

T 7

7 P

a TPPP-03-04-016

TPPP-03-04-011

P-

Port P

T-

Port T

Output Port

12-

Cam Pusher

34-

Casing Spring Guide

56-

Balance Spring Return Spring

TOKAA90-EN-00

T3-4-5

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve During Metering or Decompressing (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.

T523-02-05-001 a-

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.

TOKAA90-EN-00

T3-4-6

Pilot Pressure

Control Lever Stroke

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Front Attachment / Swing Pilot Valve 1

5 6

P 7

T P

a TPPP-03-04-007

TKAB-03-04-009

Travel Pilot Valve 1

2 T 7

3 P

6 a

8 a

a TPPP-03-04-012

TPPP-03-04-013

P-

Port P

T-

Port T

Output Port

12-

Cam Pusher

34-

Casing Spring Guide

56-

Balance Spring Return Spring

TOKAA90-EN-00

T3-4-7

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Full Stroke (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.

TOKAA90-EN-00

T523-02-05-001 a-

T3-4-8

Pilot Pressure

Control Lever Stroke

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Front Attachment/ Swing Pilot Valve 1

2 3 4 5 6

7 T P

a TPPP-03-04-009

Travel Pilot Valve 1

3 4 5 6

8 a TPPP-03-04-014 P-

Port P

T-

Port T

Output Port

12-

Cam Pusher

34-

Casing Spring Guide

56-

Balance Spring Return Spring

TOKAA90-EN-00

T3-4-9

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve (Blank)

TOKAA90-EN-00

T3-4-10

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Operation (Bucket Open/Close Pilot Valve: only Loading Shovel) The spool (7) head is hanged from the upper surface of spring guide (4). Spring guide (4) is kept raised by return spring (6).

fNOTE: Total lever stroke is determined by stroke dimension (E) of cam (1).

1 2

4 5 3 T 6

T-

Port T

P-

Port P

Output Port

12-

Cam Pusher

34-

Plate Spring Guide

56-

Balance Spring Return Spring

TOKAA90-EN-00

T3-4-11

TKAB-03-04-001

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve  Bucket Open/Close Pilot Valves 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).

a D

2. Therefore, pressure in the output port is equal to pressure in port T. C

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).

T1F3-03-09-004 a-

5. This status continues until hole (8) on spool (7) is connected to port P.

fNOTE: The pusher stroke while hole (8) on spool (7) is connected to port P is play.

TOKAA90-EN-00

T3-4-12

Pilot Pressure

Control Pedal Stroke

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve When the pedal is in neutral 1 2

4 5 3 T 6

8 P 7 a

TKAB-03-04-002

When the pedal is slightly depressed 1 2

4 5 3 T 6 8 P 7 a

TKAB-03-04-003

P-

Port P

T-

Port T

Output Port

12-

Cam Pusher

34-

Plate Spring Guide

56-

Balance Spring Return Spring

TOKAA90-EN-00

T3-4-13

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve During Metering or Decompressing (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.

a D

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, balance spring (5) is compressed and spool (7) is moved upward.

T1F3-03-09-004 a-

Pilot Pressure

P-

Port P

T-

Port T

Output Port

Balance Spring

Spool

Hole

TOKAA90-EN-00

T3-4-14

Control Pedal Stroke

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve During Metering (Output Curve: C to D)

TKAB-03-04-004

During Decompressing (Output Curve: C to D)

TOKAA90-EN-00

T3-4-15

TKAB-03-04-005

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Full Stroke (Output Curve: E to F) 1. When control pedal is set to the full stroke, cam (1) moves downward until it comes in contact with plate (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.

T523-02-05-001 a-

TOKAA90-EN-00

T3-4-16

Pilot Pressure

Control pedal Stroke

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Full Stroke (Output Curve: E to F)

4 5 3 T 6

P 7

TKAB-03-04-006

P-

Port P

T-

Port T

Output Port

12-

Cam Pusher

34-

Plate Spring Guide

56-

Balance Spring Return Spring

TOKAA90-EN-00

T3-4-17

78-

Spool Hole

SECTION 3 COMPONENT OPERATION Group 4 Pilot Valve Shockless Function (Only for Travel Pilot Valve)

2 A

3 4

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).

6 7

Operation 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.

TKAB-03-04-007

Section A-A 1

TKAB-03-04-008 12345-

TOKAA90-EN-00

T3-4-18

Damper Spring Pin Travel Pedal Travel Control Lever Support

6789-

Bracket Pin Gear 2 Gear 1

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Outline 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 (spring set hydraulic released wet-type 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 slow speed and large torque, and rotates sprocket (3) and the track. Travel brake valve (1) protects the travel circuit from being overloaded and prevents the occurrence of cavitation.

3 TKAB-03-05-001 1-

Travel Brake Valve

TOKAA90-EN-00

Travel Reduction Gear

T3-5-1

Sprocket

Travel Motor

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Travel Reduction Gear The travel reduction gear is a three-stage planetary reduction gear. Travel motor (16) 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) 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 respectively. Therefore, when ring gear (1) rotates, drum (13) and sprocket (12) also rotate.

TOKAA90-EN-00

T3-5-2

SECTION 3 COMPONENT OPERATION Group 5 Travel Device 16

13 11

12 TKAB-03-05-002 1234-

Ring Gear Third Stage Carrier Third Stage Sun Gear Second Stage Carrier

TOKAA90-EN-00

5678-

Second Stage Sun Gear First Stage Carrier Propeller Shaft First Stage Planetary Gear

9101112-

T3-5-3

Second Stage Planetary Gear Third Stage Planetary Gear Bearing Nut Sprocket

13141516-

Drum Housing Bearing Travel Motor

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Travel Motor The travel motor is a swash plate type variable displacement axial plunger motor, and consists of valve plate (6), swash plate (4), rotor (2), plungers (5), and shaft (1). Shaft (1) is connected to rotor (2) by a spline joint, and 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 ends of plungers (5) slide along swash plate (4) and the rotor (2) rotation power occurs.

TKAB-03-05-003

6 12-

Shaft Rotor

TOKAA90-EN-00

5 34-

Shoe Swash Plate

T3-5-4

Plunger

Valve Plate

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Operation When pressure oil is supplied from the pump, plungers (6) are pushed. As swash plate (9) is inclined, shoes (10) on the ends of plungers (6) slide along swash plate (9) and the rotor (12) rotation power occurs. The end of shaft (8) is connected to the propeller shaft of the travel reduction gear by a spline joint. Therefore, the rotation power of shaft (8) is transmitted to the travel reduction gear.

TKAB-03-05-004

68-

Plunger Shaft

TOKAA90-EN-00

9- Swash Plate 10- Shoe

12- Rotor

T3-5-5

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Parking Brake The parking brake is spring set hydraulic released wettype multi-disc brake. The brake is released when the brake release pressure oil is routed to brake piston chamber (a). The parking brake is automatically applied at all times unless the travel function is operated. Plates (3) are connected to rotor (4) and friction plates (2) are connected to housing (1) by a spline joint respectively. When brake is released 1. When the travel control lever is operated, pressure oil from the main pump is supplied 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 (8) on counterbalance valve spool (7). (Refer to Counterbalance Valve on T3-510.) 3. Consequently, as brake piston (5) is pushed, plates (3) which are engaged with the external circumference of rotor (4) and friction plates (2) which are engaged with the inside of housing (1) become freed each other and the brake is released.

When 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 acted on brake piston (5) is returned to the drain circuit, brake piston (5) is returned by spring (6). 3. Consequently, the spring (6) force acts on plates (3) and friction plates (2) through brake piston (5). Therefore, the external circumference of rotor (4) is secured with friction force.

c d

TKAB-03-05-005

TOKAA90-EN-00

T3-5-6

SECTION 3 COMPONENT OPERATION Group 5 Travel Device

Detail c (Counterbalance Valve)

Detail d (When brake is released)

8 5

6 P1 b

1 P2

Detail d (When brake is applied)

TKAB-03-05-006

P1- Port P1 (Pressure oil from main pump)

P2- Port P2 (Pressure oil from main pump)

Brake Piston Chamber

To Brake Piston

12-

34-

56-

Brake Piston Spring

78-

Counterbalance Valve Spool Notch

Housing Friction Plate

TOKAA90-EN-00

Plate Rotor

T3-5-7

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Travel Brake Valve The travel brake valve is located on the travel motor head and consists of the following valves.  Counterbalance Valve (1): Counterbalance valve (1) ensures smooth start/stop travel operation and prevents the machine from rollaway when traveling on a down slope. In addition, counterbalance valve (1) routes the travel motor operating pressure oil in the high-pressure port (P1 or P2) to the parking brake.  Check Valve (2): Check valve (2) assists the counterbalance valve (1) operation and prevents cavitation in the motor circuit.  Overload Relief Valve (3): Overload relief valve (3) 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): Travel motor displacement angle control valve (4) delivers the travel motor operating pressure oil in the high-pressure port (P1 or P2) to the piston.

TOKAA90-EN-00

T3-5-8

SECTION 3 COMPONENT OPERATION Group 5 Travel Device

Section A-A

4 5

2 6

3 12-

Counterbalance Valve Check Valve

TOKAA90-EN-00

Overload Relief Valve

TKAB-03-05-007

1 4-

T3-5-9

Travel Motor Displacement Angle Control Valve

56-

Port P1 Port P2

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Counterbalance Valve, Check Valve When Traveling: 1. When pressure oil from the control valve enters port P1 (3), pressure oil opens check valve (2), flows to port BM (1), and flows to the travel motor.

5. Returning oil from the travel motor flows from port AM (6) to port P2 (4) through notch (16) of counterbalance valve spool (14). As pressure oil starts flowing at this stage, the travel motor starts rotating.

2. On the other hand, returning oil from the travel motor is returned from port AM (6). However, its passage is blocked by counterbalance valve spool (14) of counterbalance valve (5).

6. When the travel control lever is returned to the neutral position, port P1 (3) and port P2 (4) are connected to the hydraulic oil tank via the control valve. Check valve (11) is closed and and pressure in oil chamber (7) decreases.

3. When pressure in port P1 (3) increases further, pressure oil from port P1 (3) flows through oil passage (12) of counterbalance valve spool (14), opens check valve (11) of counterbalance valve spool (14), and flows to oil chamber (7).

7. Therefore, counterbalance valve spool (14) and plug (9) are returned to the original position by spring (15) force and block the oil passage returning from the travel motor. Then, the travel motor rotation is stopped.

4. Plug (9) and counterbalance valve spool (14) are moved down by this oil pressure. At this time, pressure oil from port P1 (3) flows to the parking brake circuit through port A (13). Then, the parking brake is released.

8. Pressure oil in oil chamber (7) flows to port P1 (3) through orifice (8) and orifice (10) of plug (9), and returns to the hydraulic oil tank.

2 a

6 1234-

Port BM Check Valve Port P1 Port P2

TOKAA90-EN-00

5678-

Counterbalance Valve Port AM Oil Chamber Orifice

9101112-

T3-5-10

Plug Orifice Check Valve Oil Passage

13141516-

TKAB-03-05-008

Port A Counterbalance Valve Spool Spring Notch

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Detail a (During travel operation)

Detail a (When travel control lever is in neutral)

7 8 9 10 3

12 3

14 13 14

16 4

TKAB-03-05-009

TOKAA90-EN-00

T3-5-11

SECTION 3 COMPONENT OPERATION Group 5 Travel Device When Descending a Slope: 1. When the machine descends a slope, the travel motors are forcibly rotated by the machine self weight and act like a pump. 2. If the travel motor draws oil from port BM (1), pressure in port P1 (3) and oil chamber (7) decreases. Counterbalance valve Spool (14) is moved up by spring (15) force and restricts returning oil from the travel motor (port AM (6)). 3. Therefore, pressure at the port AM (6) side increases and functions as the brake of the travel motor. 4. When returning oil from the travel motor is restricted, pressure in port P1 (3) increases again and counterbalance valve spool (14) is moved down. 5. The machine descends the slope when counterbalance valve spool (14) is in the position where pressure in port P1 (3) balances with pressure at the port AM (6) side. 6. Therefore, the hydraulic brake is applied and prevents the machine from rollaway.

TOKAA90-EN-00

T3-5-12

SECTION 3 COMPONENT OPERATION Group 5 Travel Device

Detail a (When Descending a Slope)

15 4

5 TKAB-03-05-010

123-

Port BM Check Valve Port P1

TOKAA90-EN-00

45-

Port P2 Counterbalance Valve

67-

T3-5-13

Port AM Oil Chamber

14- Spool 15- Spring

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Overload Relief Valve When the travel motor circuit pressure increases beyond the set pressure, the overload 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 (2) is unseated (make-up operation) and prevents the cavitation. Operation (Shockless Function) 1. When the travel control lever (pedal) is operated by the operator, pressure oil is supplied to port P1 (3) (or P2 (4)). Pressure oil flows to motor port BM (7) (or AM (6)) of the travel motor, flows into the travel motor, and returns from motor port AM (6) (or BM (7)). Pressure oil returning from motor port AM (6) (or BM (7)) acts on poppet (12) of overload relief valve (1) (or valve (5)). 2. Pressure oil flows to spring (8) chamber through orifice (11) of poppet (12) and orifice (9) of spring seat (10). 3. Pressure oil in spring (8) chamber flows through orifice (15) of housing (13) and acts on piston (14). Then, piston (14) is moved down. 4. As pressure oil flows to piston (14), pressure in spring (8) chamber is lower than pressure in motor port AM (6). 5. Poppet (12) is pushed up by pressure in motor port AM (6). Spring seat (10) is pushed down by pressure in spring (8) chamber. At this time, as pressure in motor port AM (6) is higher, the pushing force is upward. When this upward force is stronger than the downward force of spring (8), poppet (12) is pushed up and the passage is unseated. As pressure oil in motor port AM (6) flows to motor port BM (7), pressure in motor port AM (6) decreases. (Shockless Function)

TOKAA90-EN-00

T3-5-14

SECTION 3 COMPONENT OPERATION Group 5 Travel Device 1 a

2 3

4 5

Detail a (Normal Operation)

Detail a (Relief Operation)

10 11

12 13 3 7

1234-

Overload Relief Valve Check Valve Port P1 Port P2

TOKAA90-EN-00

TKAB-03-05-011

6 5678-

Overload Relief Valve From Motor Port AM Motor Port BM Spring

9101112-

T3-5-15

Orifice Spring Seat Orifice Poppet

13- Housing 14- Piston 15- Orifice

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Operation (Overload Relief Operation)

Operation (Make-Up Operation)

1. When piston (14) reaches the stroke end, pressure in spring (8) chamber becomes equal to pressure in motor port AM (6).

1. When the machine descends a slope, the travel motors are forcibly rotated by the machine self weight and act like a pump.

2. Under this condition, the relief pressure in overload relief valve (1 or 5) becomes the set pressure.

2. When pressure in the port P1 (3) (or port P2 (4)) circuit is lower than pressure in motor port BM (7) (or motor port AM (6)), check valve (2) is unseated, pressure oil is drawn, and the lack of oil feed is compensated.

3. Poppet (12) is pushed up by pressure in motor port AM (6). Spring seat (10) is pushed down by pressure in spring (8) chamber. At this time, as the pressure receiving area in poppet (12) is larger, the pushing force is upward. When this upward force is stronger than the downward force of spring (8), poppet (12) is pushed up and the passage is unseated. As pressure oil in motor port AM (6) flows to motor port BM (7), pressure in motor port AM (6) decreases to the set pressure. As the relief operation in two-stages such as shockless function and overload relief operation prevents the travel motor from being overloaded and reduces shocks developed in the circuit when stopping the travel motor.

TOKAA90-EN-00

T3-5-16

SECTION 3 COMPONENT OPERATION Group 5 Travel Device 1 a

2 3

4 5

Detail a (Normal Operation)

Detail a (Relief Operation)

10 11

12 13 3 7

1234-

Overload Relief Valve Check Valve Port P1 Port P2

TOKAA90-EN-00

TKAB-03-05-012

6 5678-

Overload Relief Valve From Motor Port AM Motor Port BM Spring

9101112-

T3-5-17

Orifice Spring Seat Orifice Poppet

13- Housing 14- Piston 15- Orifice

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Travel Motor Displacement Angle Control Valve The travel motor displacement angle control valve changes the displacement angle of swash plate (7) by the piston (8) movement and shifts the travel mode. 2. Pressure oil from the control valve flows to port P1 or port P2 of the travel motor. (The illustration shows when pressure oil flows to port P1.) Pressure oil flows to the travel motor displacement angle control valve (1) through counterbalance valve (6). However, pressure oil is blocked by spool (3). At this time, as the circuit of piston (8) is connected to the hydraulic oil tank, piston (8) does not push swash plate (7).

Slow Speed (Displacement Angle Increase): 1. When the travel mode switch is in the slow speed position, MC (main controller) does not send the signal to solenoid valve unit (SI). Therefore, pilot port (Pi) of the travel motor displacement angle control valve (1) is connected to the hydraulic oil tank. Then, spool (3) of the travel motor displacement angle control valve (1) is pushed to the left by spring (5).

3. Therefore, the displacement angle of swash plate (7) is held to the maximum. At this time, as the stroke of plungers (9) is longer and more pressure oil to turn the travel motor is required, the travel motor turns at slow speed. (Refer to SYSTEM/Control System/Valve Control for the control circuit.)

TKAB-03-05-013

TOKAA90-EN-00

T3-5-18

SECTION 3 COMPONENT OPERATION Group 5 Travel Device 1 2

AM BM

8 AM

P1 P2 12-

Travel Motor Displacement Angle Control Valve Oil Chamber A

TOKAA90-EN-00

345-

Spool Orifice Spring

TKAB-03-05-014 678-

T3-5-19

Counterbalance Valve Swash Plate Piston

Plunger

SECTION 3 COMPONENT OPERATION Group 5 Travel Device Fast Speed (Displacement Angle Decrease): 1. When the travel mode switch is set to the fast speed position, MC (main controller) sends the signal to the solenoid valve unit (SI). (Refer to SYSTEM/ Control system/Travel Motor Displacement Angle Control.) 2. When pilot pressure from the solenoid valve unit (SI) is supplied to pilot port Pi of the travel motor displacement angle control valve (1), pilot pressure is supplied to oil chamber A (2) through orifice (4) of spool (3) and moves spool (3) to the right.

3. As spool (3) is moved, pressure oil from the control valve flows through counterbalance valve (6) and spool (3) and acts on piston (8). 4. Therefore, piston (8) pushes swash plate (7) and the displacement angle is reduced. 5. Consequently, as the stroke of plungers (9) is shorter and less pressure oil to turn the travel motor is required, the travel motor turns at fast speed.

TKAB-03-05-015

TOKAA90-EN-00

T3-5-20

SECTION 3 COMPONENT OPERATION Group 5 Travel Device 1 2

AM BM

8 AM

P1 P2 12-

Travel Motor Displacement Angle Control Valve Oil Chamber A

TOKAA90-EN-00

345-

Spool Orifice Spring

678-

T3-5-21

TKAB-03-05-016 Counterbalance Valve Swash Plate Piston

Plunger

SECTION 3 COMPONENT OPERATION Group 5 Travel Device (Blank)

TOKAA90-EN-00

T3-5-22

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve Outline 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, boom raise shockless valve (1), flow combiner valve control spool (4), and swing parking brake release spool (5).

b A

Section A-A

T178-03-06-002 TKAB-03-06-001

Pilot Valve Side

Control Valve Side

123-

Boom Raise Shockless Valve Auxiliary Auxiliary

Flow Combiner Valve Control Spool

TOKAA90-EN-00

56-

T3-6-1

Swing Parking Brake Release Spool Auxiliary

Auxiliary

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve Pilot Port Pilot Valve Side Port Name Port A Port B Port C

Connected to Right Pilot Valve Right Pilot Valve Left Pilot Valve

Port D

Left Pilot Valve

Port E Port F Port G Port H Port I Port J Port K Port L Port M

Left Pilot Valve Left Pilot Valve Right Pilot Valve Right Pilot Valve Travel Pilot Valve Travel Pilot Valve Travel Pilot Valve Travel Pilot Valve Auxiliary Pilot Valve (BH) Bucket Close Pilot Valve (LD) Auxiliary Pilot Valve (BH) Bucket Open Pilot Valve (LD) Pressure Sensor (SA) Pressure Sensor (SB) 2-Spool Solenoid Valve Unit Pilot Shut-Off Solenoid Valve Swing Parking Brake Hydraulic Oil Tank

Port N Port SA Port SB Port PI Port PH Port SH Port DF

Remark Boom Raise Pilot Pressure Boom Lower Pilot Pressure Arm Roll-In Pilot Pressure (BH) Arm Extend Pilot Pressure (LD) Arm Roll-Out Pilot Pressure (BH) Arm Retract Pilot Pressure (LD) Swing (Left) Pilot Pressure Swing (Right) Pilot Pressure Bucket Roll-In Pilot Pressure Bucket Roll-Out Pilot Pressure Travel (Left Forward) Pilot Pressure Travel (Left Reverse) Pilot Pressure Travel (Right Forward) Pilot Pressure Travel (Right Reverse) Pilot Pressure Auxiliary Pilot Pressure (BH) Bucket Close Pilot Pressure (LD) Auxiliary Pilot Pressure (BH) Bucket Open Pilot Pressure (LD) Via Hose Via Hose Primary Pilot Pressure Primary Pilot Pressure (Heat Circuit) Brake Release Pressure Returning to Hydraulic Oil Tank

fNOTE: BH: Backhoe LD: Loading Shovel

TOKAA90-EN-00

T3-6-2

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve

Pilot Valve Side

G N

PI K

I J

TOKAA90-EN-00

T3-6-3

TKAB-01-02-025

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve

Control Valve Side Port Name Port 1 Port 2 Port 3

Connected to Control Valve Control Valve Control Valve

Port 4

Control Valve

Port 5 Port 6 Port 7 Port 8 Port 9 Port 10 Port 11 Port 12 Port 13

Control Valve Control Valve Control Valve Control Valve Control Valve Control Valve Control Valve

Port 14

Control Valve

Port S3 Port SE Port SM Port SN Port SP Port SL Port SK Port TR

Pressure Sensor (Swing) 5-Spool Solenoid Valve 5-Spool Solenoid Valve Control Valve Pressure Sensor (Travel)

Remark Boom Raise Pilot Pressure Boom Lower Pilot Pressure Arm Roll-In Pilot Pressure (BH) Arm Extend Pilot Pressure (LD) Arm Roll-Out Pilot Pressure (BH) Arm Retract Pilot Pressure (LD) Plug Plug Bucket Roll-In Pilot Pressure Bucket Roll-Out Pilot Pressure Travel (Left Forward) Pilot Pressure Travel (Left Reverse) Pilot Pressure Travel (Right Forward) Pilot Pressure Travel (Right Reverse) Pilot Pressure Auxiliary Pilot Pressure (BH) Bucket Close Pilot Pressure (LD) Auxiliary Pilot Pressure (BH) Bucket Open Pilot Pressure (LD) Plug Returning to Hydraulic Oil Tank Plug Returning to Hydraulic Oil Tank Flow Combiner Valve Control Pressure Plug -

fNOTE: BH: Backhoe LD: Loading Shovel

TOKAA90-EN-00

T3-6-4

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve

Control Valve Side

1 5 13

S3 7 6 14

9 10

SL 12

TOKAA90-EN-00

T3-6-5

TKAB-01-02-057

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve (Blank)

TOKAA90-EN-00

T3-6-6

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve Shuttle Valve The shuttle valve selects pilot pressure used to perform each operation and routes pilot pressure to the flow combiner valve control spool and the swing parking brake release spool. The spools corresponding to each operation are as follows:

Boom Raise Boom Lower Arm Roll-Out (BH) Arm Retract (LD) Arm Roll-In (BH) Arm Extend (LD) Bucket Roll-In Bucket Roll-Out Swing (Right) Swing (Left) Travel (Right) Travel (Left) Auxiliary (BH) Bucket Close (LD) Auxiliary (BH) Bucket Open (LD)

Flow Combiner Valve Control Spool -

Swing Parking Brake Release Spool  



 -

    -



fNOTE: BH: Backhoe LD: Loading Shovel

TOKAA90-EN-00

T3-6-7

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve

m 8 9

abcd-

Travel (Left) Travel (Right) Swing Arm

efgh-

1234567-

Travel (Right) Travel (Left) Bucket Arm Boom Swing Auxiliary (BH), Bucket Open/ Close (LD)

Bucket Close (LD) Bucket Open (LD) Boom Bucket

14 13

Flow Combiner Valve Control Spool Swing Parking Brake Release Spool

Swing, Auxiliary (BH), Bucket Open/Close (LD) 9- Boom, Arm 10- Arm, Boom Raise, Swing, Auxiliary (BH), Bucket Open/ Close (LD) 11- Arm, Boom Raise

12- Boom, Arm, Bucket, Swing, Auxiliary (BH), Bucket Open/ Close (LD) 13- Boom, Arm, Bucket 14- Boom, Arm, Bucket, Travel (Right)

fNOTE: BH: Backhoe LD: Loading Shovel

TOKAA90-EN-00

11 10

T3-6-8

TKAB-03-06-003

m- Boom Raise Shockless Valve

15- Boom Raise, Arm, Swing, Travel (Left), Auxiliary (BH), Bucket Open/Close (LD) 16- Boom, Arm, Bucket, Travel (Right) 17- Travel (Left), Travel (Right)

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve

Pilot Valve Side

A A

TKAB-03-06-001

Section A-A

10 3

16 15

14 17 T178-03-06-009

TOKAA90-EN-00

T3-6-9

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve Shockless Valve

The shockless valve is provided in the boom raise circuit and functions during boom lowering operation or when stopping boom raise operation. During boom raise operation 1. Boom raise pilot pressure acts on spool (1) through port A (2).

2. Immediately after operation is started, pilot pressure is low. The pilot pressure oil flows to the spring B (3) chamber through clearance C between spool (1) and housing (7) and inner passage 3 (9). At the same time, pilot pressure oil flows to the port 1 (4) side through inner passage 2 (5).

9 T1V1-03-06-003

T1V1-03-06-002

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.

1234-

TOKAA90-EN-00

T3-6-10

Spool Port A Spring B Port 1

569-

Inner Passage 2 Spring A Inner Passage 3

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve During boom raise operation: 6

9 4

T183-03-06-003

T183-03-06-004

Detail of Clearance C

1 T1V1-03-06-008

12-

Spool Port A

TOKAA90-EN-00

34-

Spring B Port 1

56-

T3-6-11

Inner Passage 2 Spring A

79-

Housing Inner Passage 3

SECTION 3 COMPONENT OPERATION Group 6 Signal Control 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 acts on 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).

8 9

3. Port 1 (4) is connected to the spring A (6) side in spool (1) through inner passage 1 (8) and to the spring B (3) chamber through inner passage 3 (9).

4. Pressure oil in the spring B (3) chamber flows from clearance C between spool (1) and housing (7) and pressure in the spring B (3) chamber decreases. Spool (1) is moved to the right by the pressure acts on the spring A (6) side. Therefore, clearance C between spool (1) and housing (7) is closed and pressure oil is blocked.

7. Consequently, the shockless valve reduces the shock during boom lower operation or when stopping boom raise operation.

TOKAA90-EN-00

T1V1-03-06-002

5. When clearance C is closed, pressure in the spring B (3) chamber 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.

T1V1-03-06-004

1234-

T3-6-12

Spool Port A Spring B Port 1

689-

Spring A Inner Passage 1 Inner Passage 3

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve During boom lower operation or when stopping boom raise operation (shock reducing operation) 6

T183-03-06-005

T183-03-06-004

Detail of Clearance C

1 T1V1-03-06-008

123-

Spool Port A Spring B

TOKAA90-EN-00

456-

Port 1 Inner Passage 2 Spring A

789-

T3-6-13

Housing Inner Passage 1 Inner Passage 3

SECTION 3 COMPONENT OPERATION Group 6 Signal Control Valve Flow Combiner Valve Control Spool, Swing Parking Brake Release Spool

Flow Combiner Valve Control Spool

fNOTE: Two spools are identical in operational principle.

 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.  The swing parking brake release spool is shifted by the boom, arm, bucket, swing, auxiliary 1, and positioning/ auxiliary 2 pilot pressure and supplies primary pilot pressure to the swing motor.

T178-03-06-014

ab-

To Hydraulic Oil Tank Primary Pilot Pressure

cd-

To Flow Combiner Valve Travel (Right) Pilot Pressure

Spool

Spring

Swing Parking Brake Release Spool 1

T178-03-06-014

TOKAA90-EN-00

ab-

To Hydraulic Oil Tank Primary Pilot Pressure

ef-

To Swing Motor Boom, Arm, Bucket, Swing, Auxiliary 1/Auxiliary 2

Spool

Spring

T3-6-14

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) 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.

Section Z-Z

T1 to T4

P A1 to A4

1 HT

T1V1-03-07-012

T1 T2 T3

A3 Z

T4 A4

T1V1-03-07-011

P- Pressure Oil from Pilot Pump A1- Pilot Pressure to Travel Pilot Valve A2- Pilot Pressure to Boom, Bucket Pilot Valve

A3- Pilot Pressure to Arm, Swing Pilot Valve A4- Unused (BH), Pilot Pressure to Bucket Open/Close Pilot Valve (LD)

T1- Returning Oil from Travel Pilot Valve T2- Returning Oil from Arm, Swing Pilot Valve T3- Returning Oil from Boom, Bucket Pilot Valve

Spool

TOKAA90-EN-00

T3-7-1

T4- Returning Oil to Hydraulic Oil Tank HT- Pilot Pressure to Signal Control Valve (Port PH)

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure)  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.)

Pilot Shut-Off Lever: LOCK Position

T1 to T4

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 A4) is connected to the hydraulic oil tank.

4. Therefore, even if the control/travel control lever is operated, the pilot valve is not activated.

A1 to A4

 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.)

1 T1J1-03-07-011

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 and signal control valve. Pilot Shut-Off Lever: UNLOCK Position

3. Consequently, when the control/travel control lever is operated, the pilot valve is activated.

T1 to T4

P A1 to A4

1 T1J1-03-07-001 P- Pressure Oil from Pilot Pump A1- Pilot Pressure to Travel Pilot Valve A2- Pilot Pressure to Boom, Bucket Pilot Valve A3- Pilot Pressure to Arm, Swing Pilot Valve A4- Unused (BH), Pilot Pressure to Bucket Open/Close Pilot Valve (LD)

TOKAA90-EN-00

T3-7-2

Spool

T1- Returning Oil from Travel Pilot Valve T2- Returning Oil from Arm, Swing Pilot Valve T3- Returning Oil from Boom, Bucket Pilot Valve T4- Returning Oil to Hydraulic Oil Tank HT- Pilot Pressure to Signal Control Valve (Port PH)

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Solenoid Valve The solenoid valve consists of the 4-spool solenoid valve unit to control the valve and the 2-spool solenoid valve unit. 4-Spool Solenoid Valve Unit

The 4-spool solenoid valve unit controls the control valve and the valve in travel motor according to the signal from MC (main controller). (Refer to SYSTEM/ Control System.) The 4-spool solenoid valve unit consists of proportional solenoid valves (SC, SF, SI, and SG). SC : This valve controls the travel motor displacement angle control valve. SF : This valve increases pressure of the main relief valve in control valve. SI : This valve controls the boom overload relief selector valve in control valve. SG : This valve controls the bypass shut-out valve (4-spool side) in control valve.

TKAB-03-07-009

2-Spool Solenoid Valve Unit The 2-spool solenoid valve unit controls the control valve according to the signal from MC (main controller). (Refer to SYSTEM/Control System.) The 2-spool solenoid valve unit consists of proportional solenoid valves (SC and SI).

SC : This valve controls the bypass shut-out valve (5-spool side) in control valve. SI : This valve controls the arm 2 flow rate control valve (selector valve) in control valve.

TKAB-03-07-010

TOKAA90-EN-00

T3-7-3

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) 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.  When in neutral 1. Spring (2) pushes spool (1) to the right and output port S is connected to tank port T.

 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.

a TDAA-03-07-013

Spool

TOKAA90-EN-00

Spring

T3-7-4

Solenoid

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Fan Motor The fan motor is a swash plate type axial plunger motor. The fan motor consists of rotor (1), shaft (2), swash plate (3), shoes (4), retainer (5), and plungers (6). Operational principle of the fan motor is the same as that of the swing motor. (Refer to Swing Device.)

12-

Rotor Shaft

TOKAA90-EN-00

34-

Swash Plate Shoe

TJAE-03-07-001

56-

T3-7-5

Retainer Plunger

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Fan Valve The fan valve consists of relief valves (1) and, fan reverse rotation control solenoid valve (2) and the fan reverse rotation spool (3). When pressures in the fan pump circuit reaches the set pressure, relief valve (1) makes pressure oil flow to the hydraulic oil tank. When the fan motor circuit pressure decreases, the fan valve draws hydraulic oil from the hydraulic oil tank and prevents the occurrence of cavitation (make-up function). The fan reverse rotation control solenoid valve (2) shifts the fan reverse rotation spool (3) according to the signal from MC (main controller). The fan reverse rotation spool (3) shifts the port through which pressure oil flows to the fan motor, and rotates the fan motor in normal or reverse rotation. (Refer to SYSTEM/ Control System.)

2 PP

T1 1

T1J1-03-07-004

M1- Port M1 (To Fan Motor: Normal Rotation, From Fan Motor: Reverse Rotation)

M2- Port M2 (From Fan Motor: Normal Rotation, To Fan Motor: Reverse Rotation)

P1- Port P1 (From Fan Pump) T1- Port T1 (To Hydraulic Oil Tank) PP- Port PP (From Pilot Pump)

Relief Valve

TOKAA90-EN-00

Fan Reverse Rotation Control Solenoid Valve

T3-7-6

Fan Reverse Rotation Spool

TJAG-03-07-001

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure)

Section A

TKAB-03-07-005

TOKAA90-EN-00

T3-7-7

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure)

Relief Operation 1. Pressure at port P1 (from fan pump) acts on pilot poppet (3) through orifice (1) in piston (2).

5. When the fan circuit pressure is decreased to the specified level, piston (2) and main poppet (9) are closed by the spring A (8) force.

2. When the force generated by pressure at port P1 reaches the set pressure of spring B (4), pilot poppet (3) is opened. Pressure oil from passage A (5) flows along the external circumference of sleeve (6) and flows to port T1 (to hydraulic oil tank). 3. At this time, a pressure difference occurs between port P1 and spring chamber (7) due to orifice (11). 4. When the force generated by this pressure difference reaches the set pressure of spring A (8), main poppet (9) is opened and pressure oil from port P1 flows to port T1. Then, pressure increase from the fan pump is prevented.

a TKAB-03-07-006

Detail a

T1 9

TKAB-03-07-007

P1 P1- From Fan Pump

T1- Port T1 (To Hydraulic Oil Tank)

123-

456-

Orifice (Groove Part) Piston Pilot Poppet

TOKAA90-EN-00

Spring B Passage A Sleeve

789-

T3-7-8

Spring Chamber Spring A Main Poppet

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure)

Make-Up Operation 1. Sleeve (6) is pushed to the left by the force generated by pressure at port P1 (from fan pump) and the spring C (10) force. Sleeve (6) is pushed to the right by the force generated by pressure at port T1 (to hydraulic oil tank). 2. When pressure in port P1 decreases lower than pressure in port T1, sleeve (6) is moved to the right. 3. Hydraulic oil in port T1 flows to port P1 and cavitation is prevented. 4. When pressure in port P1 increases to the specified pressure, sleeve (6) is closed by the force of spring C (10).

a TKAB-03-07-006

Detail a-1

T1 TKAB-03-07-008 Detail a-2

T1 TKAB-03-07-014 P1- From Fan Pump

T1- Port T1 (To Hydraulic Oil Tank)

10- Spring C

Sleeve

TOKAA90-EN-00

T3-7-9

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) 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 12-

TOKAA90-EN-00

T3-7-10

Port P Pilot Relief Valve

Pilot Filter

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Shockless Valve The shockless valve is provided in the boom lower pilot operation control circuit. When suddenly returning the boom lower control lever, the shockless valve dampens the boom spool returning speed. Operation 1. When returning the boom lower control lever, returning oil from the spool at the boom lower side in the control valve acts on port A. 6

2. Pressure oil in port A flows to chamber D (1) through orifice (6). 3. Pressure oil in chamber D (1) flows through passage (2) between spool (5) and housing (4) to port B. 4. A pressure difference is developed between the front and rear of orifice (6). Then, spool (5) is moved to the right by pressure acting on the spring A (3) side and spring A (3) force. Therefore, passage (2) between spool (5) and housing (4) becomes narrower, and pressure oil is reduced. 5. When passage (2) is closed, pressure in chamber D (1) is equal to pressure in port A. Then, spool (5) is moved to the left by the spring B (7) force. Passage (2) is opened again and pressure oil flows to port B. 6. As the operation in step 3 to step 5 is repeated and pressure oil is gradually returned to the port B side, the control valve spool is returned slowly.

TOKAA90-EN-00

T3-7-11

TKAB-03-07-011

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure)

TKAB-03-07-012

AB-

Port A Port B

12-

Chamber D Passage

TOKAA90-EN-00

34-

Spring A Housing

56-

T3-7-12

TKAB-03-07-013

Spool Orifice

Spring B

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Accumulator The accumulator is provided in the pilot circuit. The accumulator buffers fluctuations in oil pressure and maintains the pilot pressure for a short time period after the engine is stopped. The accumulator mainly consists of body (3), holder (4), nitrogen gas (N2) (1) and bladder (2).

 Pressure oil from the pilot pump is routed to the accumulator through port A and compresses bladder (2) until pressure oil balances with nitrogen gas (N2) (1) in bladder (2).

 When pressure oil is stopped supplying due to engine stopping, bladder (2) starts expanding and supplies accumulated pressure oil (B) to the pilot circuit through port A.

T105-02-10-003

TOKAA90-EN-00

A-

Port A

B-

Accumulated Pressure Oil

12-

Nitrogen Gas (N2) Bladder

34-

Body Holder

T3-7-13

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Auto-Lubrication System The auto-lubrication system automatically applies grease to front joint pins (a to f ). The auto-lubrication system consists of grease pump (1), pail (5) or grease tank (6), distribution valve (3), the lubrication mode selection switch (8), and Auto/Manual selector valve (2). Distribution valve (3) has two types, which differ depending on the operation. The auto-lubrication system is shifted to three modes, AUTO, MANUAL, and OFF by the lubrication mode selection switch (8) in the cab.

In case of AUTO, grease pump (1) is automatically operated or stopped according to the interval set by MC1 (main controller 1) (7), and applies grease. The lubrication interval can be changed by using the Auto-Lubrication screen on the monitor. In case of MANUAL, auto-lubrication is not performed. Lubrication is manually performed by grease gun (4). In case of OFF, lubrication is not performed.

8 7

a b c d e 5, 6

f 4

123-

Grease Pump Auto/Manual Selector Valve Distribution Valve

TOKAA90-EN-00

456-

Grease Gun Pail Grease Tank (Option)

78-

T3-7-14

MC1 Lubrication Mode Selection Switch

TKAB-03-07-003

a~f- Front Joint Pin (Point for Lubrication)

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Quicklub Lubrication System (Standard) 2

1 8 5

TKAB-01-02-056

TKAB-01-02-005

Centro Matic Lubrication System (Option)

TOKAA90-EN-00

TKAB-01-02-039

T3-7-15

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Distribution Valve (Quicklub Lubrication System) (Standard)

Distribution valve (13) is installed in the auto-lubrication circuit and distributes grease from the grease pump to each point for lubrication. Proximity switch (14) detects the distributed grease amount and sends the signal to MC1 (main controller 1). (Refer to SYSTEM/Control System/Auto-Lubrication Control.)

T1J1-03-07-005 13- Distribution Valve

14- Proximity Switch

Operation a

1. Grease from the grease pump is supplied through passage G (G) and acts on the right side of piston (15)-A.

15 11

2. Therefore, piston (15)-A is moved to the left. Grease at the left side of piston (15)-A is delivered to port 2 (2) through passage H (H) and piston (15)-F.

G T1J1-03-07-006

TOKAA90-EN-00

aH-

From Grease Pump Passage H

G-

Passage G

1234567-

Port 1 Port 2 Port 3 Port 4 Port 5 Port 6 Port 7

8910111215-

Port 8 Port 9 Port 10 Port 11 Port 12 Piston

T3-7-16

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) 3. As piston (15)-A is moved to the left, grease from the grease pump is supplied through passage I (I) and acts on the right side of piston (15)-B.

a 15

4. Therefore, piston (15)-B is moved to the left. Grease at the left side of piston (15)-B is delivered to port 11 (11) through passage J (J) and piston (15)-A.

T1J1-03-07-007

5. As piston (15)-B is moved to the left, grease from the grease pump is supplied through passage K (K) and acts on the right side of piston (15)-C.

aI-

From Grease Pump Passage I

J-

Passage J

1234567-

Port 1 Port 2 Port 3 Port 4 Port 5 Port 6 Port 7

8910111215-

Port 8 Port 9 Port 10 Port 11 Port 12 Piston

6. Therefore, piston (15)-C is moved to the left. Grease at the left side of piston (15)-C is delivered to port 9 (9) through passage L (L) and piston (15)-B.

a L

7. As the operation in step 3 to step 6 is repeated, grease is delivered to ports 11, 9, 7, 5, and 3 in sequence.

T1J1-03-07-008

TOKAA90-EN-00

aK-

From Grease Pump Passage K

L-

Passage L

1234567-

Port 1 Port 2 Port 3 Port 4 Port 5 Port 6 Port 7

8910111215-

Port 8 Port 9 Port 10 Port 11 Port 12 Piston

T3-7-17

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) 8. As piston (15)-F is moved to the left, grease from the grease pump is supplied through passage H (H) and acts on the left side of piston (15)-A.

a 15

9. Therefore, piston (15)-A is moved to the right. Grease at the right side of piston (15)-A is delivered to port 1 (1) through passage G (G) and piston (15)F.

10. As piston (15)-A is moved to the right, grease from the grease pump is supplied through passage J (J) and acts on the left side of piston (15)-B.

aG-

From Grease Pump Passage G

H-

Passage H

1234567-

Port 1 Port 2 Port 3 Port 4 Port 5 Port 6 Port 7

8910111215-

Port 8 Port 9 Port 10 Port 11 Port 12 Piston

11. Therefore, piston (15)-B is moved to the right. Grease at the right side of piston (15)-B is delivered to port 12 (12) through passage I (I) and piston (15)A.

T1J1-03-07-009

a 15

12. As the operation in step 10 to step 11 is repeated, grease is delivered to ports 12, 10, 8, 6, and 4 in sequence. Then, grease is delivered to all ports.

T1J1-03-07-010

TOKAA90-EN-00

aI-

From Grease Pump Passage I

J-

Passage J

1234567-

Port 1 Port 2 Port 3 Port 4 Port 5 Port 6 Port 7

8910111215-

Port 8 Port 9 Port 10 Port 11 Port 12 Piston

T3-7-18

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) Distribution Valve (Centro Matic Lubrication System) (Option)

3. When the grease pump is stopped, the piston in valve (1) is moved down by the spring force. Grease under the piston flows to the upper of the piston through the inner passage.

The distribution valve (option) has manifold (2) to which valves (1) are installed. The piston and spring are built in each valve (1).

4. The piston stroke can be changed by adjusting indicator pin (3) in the upper of valve (1). Therefore, the grease delivery amount can be adjusted every valve (1).

1. Grease which is supplied from the grease pump to grease inlet port (a) flows to each valve (1). 2. Grease raises the piston in valve (1). The piston pushes grease in the upper of the piston out of grease outlet port (b), and is stopped. Grease is supplied to each point for lubrication.

3 1

a b TKAB-03-07-004

Grease Inlet Port

Grease Outlet Port

Valve

Manifold

TOKAA90-EN-00

T3-7-19

Indicator Pin

SECTION 3 COMPONENT OPERATION Group 7 Others (Upperstructure) (Blank)

TOKAA90-EN-00

T3-7-20

SECTION 3 COMPONENT OPERATION Group 8 Others (Undercarriage) 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), seals (2, 4), rods (8), and turn buckles (7). 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 shafts of the swing reduction gears.

6 4

8 W142-03-01-002

12-

Outer Race Seal

TOKAA90-EN-00

34-

Inner Race Seal

56-

T3-8-1

Support Ball

78-

Turn Buckle Rod

SECTION 3 COMPONENT OPERATION Group 8 Others (Undercarriage) Center Joint The center joint is a joint which can turn freely. When the upper structure swings, the center joint eliminates twisting of the hoses and allows hydraulic oil to flow the travel motors. Spindle (1) is secured to the upperstructure and can not 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 leaks between spindle (1) and body (2).

Section A-A

f a

b d

2 A

a b-

Travel (Left Reverse) Travel (Right Forward)

Spindle

TOKAA90-EN-00

TJAA-03-08-001

cd-

Travel (Right Reverse) Travel (Left Forward)

Body

3 TJAA-03-08-002

ef-

Pilot Port for Travel Mode Control Drain

Seal

T3-8-2

SECTION 3 COMPONENT OPERATION Group 8 Others (Undercarriage) Track Adjuster The track adjuster consists of adjuster cylinder (1) and spring (3) , and is held by the side frame. The track adjuster absorbs the load applied to the front idler at spring (3). Track sag is adjusted by grease amount in adjuster cylinder (1).

Detail C

 When grease is supplied through grease fitting (5), grease fills chamber (a) in adjuster cylinder (1), pushes piston rod (2), and reduces track sag.  Loosen hexagonal part (b) of valve (10) by 1 to 1.5 turns and drain grease when loosening the tracks.

M17F-07-005

T18J-03-08-001

Hexagonal Part

123-

Adjuster Cylinder Piston Rod Spring

TOKAA90-EN-00

567-

Grease Fitting Nut Flange

8- Washer 9- Spacer 10- Valve

T3-8-3

11- Grease Outlet

SECTION 3 COMPONENT OPERATION Group 8 Others (Undercarriage) (Blank)

TOKAA90-EN-00

T3-8-4

MEMO

TOKAA90-EN-00

MEMO

TOKAA90-EN-00

Hitachi Construction Machinery Co., Ltd. Attn: PS Information Center Tel: 81-29-832-7084 Fax: 81-29-831-1162 E-mail: HCM-TIC-GES@hitachi-kenki.com

Hitachi Ref. No.

SERVICE MANUAL REVISION REQUEST FORM COMPANY NAME: YOUR NAME: DATE: FAX: E-mail:

MODEL: PUBLICATION PART NO.:

(Located at the left top corner in the cover page)

PAGE NO.:

(Located at the bottom center in the page. If two or more revisions are requested, use the comment column)

YOUR COMMENTS / SUGGESTIONS: Attach photo or sketch if required. If your need more space, please use another sheet.

REPLY:

TOKAA90-EN-00

(Copy this form for usage)