Discover Engineering by PCS Edventures by PCS Edventures

v050214

Project

PULLEYS

Engineering Each step is color coded in order of assembly.

Pulley Systems

First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Option 1

Option 2

Flip assembly.

Materials you will need:

Building Block 30 (Qty 19)

Building Block 15 with Bore (Qty 2)

String (Qty 1)

Link 30 (Qty 2)

Building Block 15 (Qty 2)

I-Strut 30 (Qty 4)

Base Plate 120x60 (Qty 2)

Angle Block 7.5 (Qty 4)

Angle Girder 7.5 (Qty 2)

Angle Girder 120 (Qty 8)

Rope Pulley 21 (Qty 5)

Coupling 30 (Qty 1)

Metal Axle 60 (Qty 1)

Hook (Qty 5)

Spring Cam (Qty 6)

Metal Axle 125 (Qty 1)

Clip 5 (Qty 12)

Clip Axle 30 (Qty 2)

Spacer Ring (Qty 6)

Clip Axle 45 (Qty 2)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

2 1

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order.

All steps have an “exploded view” which helps with assembly.

x15

The assembly should look like this before proceeding to the next step. Shown in actual color.

3 2

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Fifth

4 3

From Step 1

5 4 x1

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x1 30

6 x4

Make sure the Angular Block 7.5s are turned in toward each other so the sloped face of the block is facing inward.

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5 8

From Step 6

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9 2 From Step 7

From Step 7

10 3 Note the orientation of both Building Block 30s.

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x2 The center groove should have a horizontal orientation on both Building Block 30’s.

5 12 The center groove on the Building Block 30 should be horizontal. x1

Note the placement and spacing of the Coupling 30 and Building Block 15s.

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13 2 60

14 3 x2

Adjust the Metal Axle 60 as needed when adding the Rope Pulley 21

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From Step 10

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16 2 x1

125

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17 4 30

This pulley assembly will be used in Option 1.

5 18 45

x1 x6

This pulley assembly will be used in Option 2.

Option 1 Start Tie the end of the string around the top Hook.

From Step 17

From Step 4

Tie a small loop in the string to hold, or to hook on to the bottom hook.

Option 2 Start Tie the end of the string around the top Hook.

From Step 18

From Step 4

Tie a small loop in the string to hold, or to hook on to the bottom hook.

Finished Model

Option 1

Option 2

What You Will Learn By combining multiple pulley systems, one can gain a powerful MA, substantially decreasing the amount of force needed to move a load. Therefore, the more attachment points (rope passes over a moving pulley) the more of a MA. In a multi pulley system, the ratio can be calculated by counting the rope lengths that come from a moving pulley.

How has it changed the world? A pulley is one of the six simple machines. Pulleys are generally used to raise, lower, or move a load so lifting may be done more easily and without a lot of power from a motor. This is possible because a pulley redirects the force (push or pull). There are three types of pulley systems: fixed, movable, and compound. In this project, you will test the three types of pulley systems to determine the amount of force vs. effort necessary to lift a load. Pulleys began making life easier around 220 BC. The Great Pyramid of Giza and other wonders of the ancient world used pulley systems to position building materials in place. Pulleys were also used to load heavy cargo on to large ships, trains cars, and freight trucks. Today, pulleys are used in many aspects of life. Some common examples are large cranes that lift and place building materials and/or heavy cargo, elevators, fishing boats, water wells, and zip lines. What pulleys have you seen and/or used?

Where is the Math? A pulley offers mechanical advantage (MA) which is the calculation of how much faster and easier a machine makes your work. In a pulley system, the MA is determining the load over effort. The load is the weight of the object being moved and the effort is the force needed to move the object. The mathematical equation is MA = load/effort. This equation represents the ratio of load to the force applied to it.

Try This

Option 1

Option 2

These are both examples of block and tackle compound pulley systems. A block and tackle is assembled so one block is attached to fixed mounting point and the other is attached to the moving load. The mechanical advantage of a block and tackle system is equal to the number of parts of the rope that support the moving block. •

Attach the weight and rope on the hooks and pulleys as shown in Option 1. Detach the string from the bottom hook and slowly pull downward so the weight moves upward. Continue to release and pull on the weight until you have a good sense of the effort needed to lift it with this pulley system.

•

Attach the weight and rope on the books and pulleys as shown in Option 2. Detach the string from the bottom hook and slowly pull downward so the weight moves upward. Continue to release and pull on the weight until you have a good sense of the effort needed to lift it with this pulley system.

1. Can you feel the difference between the two pulley systems?

__________________________________________________________________________________________________

v021314

Project

LEVERS

Engineering Each step is color coded in order of assembly.

Trebuchet

First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 39)

Building Block 15 with Bore (Qty 7)

Building Block 15 (Qty 3)

Building Block 7.5 (Qty 1)

Angle Girder 30 (Qty 2)

Angle Girder 120 (Qty 2) Angle Block 15 (Qty 1)

Angle Block 30 (Qty 4)

Angle Block 60 (Qty 5)

Spacer Ring (Qty 6)

Clip 5 (Qty 5)

Clip Axle 60 (Qty 1)

I-Strut 30 (Qty 2)

Clip Axle 30 (Qty 3)

String (Qty 1)

Base Plate 120x60 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

2 1

Second

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order. All steps have an “exploded view” which helps with assembly.

60 30

Shown in actual color.

The assembly should look like this before proceeding to the next step.

3 2

Note the orientation of the assemblies from Step 1. Attach the Angle Block 30s to the Building Block 30s.

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3 t2

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Sl ot 1

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Leave the assemblies hanging over the edge of the base plate.

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2 4

3 5 The grooves in the Building Block 15s must be parallel. x6

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7 5 x6

Hold the Building Block 15s with Bore in place for the next step.

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2 8

From Step 5

9 3 x1

60 15

60 x1

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30 x1

From Step 8

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2 11 30 30

Place one of the assemblies aside until Step 13.

12 3

From Step 11

From Step 10

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From Step 11

5 14

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x10

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2 17 From Step 12

x4 30 30

The counterweight assembly will hang freely.

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Create a projectile for the trebuchet.

Fold the string into a loop. x1

Push the loop through the center hole in the Building Block 15 with Bore.

Slide the free end of the string through the loop.

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2 19

Pull the string tight and then fold the free end over onto itself.

Create a loop with the end of the string and tie a knot to secure it.

Finished Model

1. Pull back the lever arm to test it. Does it swing freely? 2. Hook the loop of the projectile around the Clip Axle 30. 3. Hold the base of the model and pull the arm back. Place the projectile beneath the lever arm, and let go of the arm. 4. Does the projectile launch?â&#x20AC;&#x2C6;

Engineering A lever is a simple machine. Nearly every tool or complex machine that is used contains a lever. There are three parts of a lever, the Effort, Fulcrum, and Load. A fulcrum is a support upon which the lever pivots, like the center of a see-saw. The Effort is the mechanical force that can be applied to another object or resistance force, which is called the Load.

lever’s weight dropping is then transferred to the load the on the opposite end of the trebuchet arm. Because the load isn’t attached to the trebuchet, the effort causes the load to be launched!

As a lever pivots on the fulcrum, the effort used to pull on the lever is transferred to the load. The farther the distance (the longer the lever) from the fulcrum, the more the effort is transferred to the load. This is why it is easier to lift a rock with a long stick braced on the fulcrum than it is using a short one.

Effort

Fulcrum

Load

There are three different classes of levers based upon the relationship between the position of the fulcrum, load, and the applied force/effort.

Class 1

Effort

Load

Fulcrum

Class 2

Load Effort

Fulcrum Class 3 Effort Load

How has it changed the world? It is very possible that the lever was the first simple machine ever discovered, because simple objects such as sticks can easily be used levers. Chimpanzees are even able to use sticks as levers. You use levers every day, often without even realizing it. Some common levers are sink faucets, light switches, door knobs, and scissors. Have you ever tried to turn on a faucet where the handle (lever) was missing?

Fulcrum

The arm of the trebuchet is a lever and is connected to the base at the fulcrum. The large weight on the trebuchet is where the effort pulls on the lever. (Gravity is the effort which acts upon the weight in this application.) The force (effort) created by the

Try This Remove the counterweights (Building Block 30s), two sections at a time, and see how this affects the distance the block is thrown by the trebuchet. Record what differences each change makes.

Return the counterweights to the trebuchet and use additional girders to extend the length of the arm and see how this affects the distance the block is thrown.

v021314

Project

WORM GEARS P roject #3 - W orm G ears

Engineering

Worm Gear

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 6)

Building Block 15 with Bore (Qty 3)

Gear Wheel T20 (Qty 1)

Building Block 15 (Qty 2)

Building Block 15 with 2 Pins (Qty 1)

Bearing Sleeve (Qty 2)

Clip Axle 45 (Qty 3)

Worm m=1.5 (Qty 1)

Crank Shaft (Qty 2)

Hub Nut (Qty 1)

Clip 5 (Qty 1)

Spacer Ring (Qty 5)

Hub Collet (Qty 1)

Spring Cam (Qty 2)

Base Plate 120x60 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

1 2

Second

Third

Fourth

Fifth

Sixth

All steps have an “exploded view” which helps with assembly.

Slo t1 3

x2 t5

Slo

The assembly should look like this before proceeding to the next step.

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Sixth

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2 3

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4 3 x2

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5 x1

From Step 2.

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4 7

5 8

From Step 6.

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Sixth

Be sure the slots on the ends of both Building Block 30s are horizontal and the pins are facing away from the center of the model.

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10 x1

11 45

Once positioned on the axle, tighten the Hub Nut fully until it can no longer turn freely on the axle.

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12 x2

Be sure the teeth of the Spur Gear 20 mesh with the Worm Gear.

Sixth

Finished Model

Engineering Worm gears are gears with one continuous tooth wrapped in a spiral around a central axle. A worm gear is much like a screw that is used in woodworking. As a screw spins, the spiral around the screw pulls itself into the material such as a wood screw burrowing into a piece of wood.

A worm gear works in a similar way. When the worm gear spins, the spirals around the worm gear pull on the teeth of the spur gear, causing it to rotate.

How has it changed the world?

The benefit of a worm gear is that the spur gear cannot spin the worm gear. When the spur gear tries to rotate, it only presses against the sides of the spirals around the worm gear. This can be used to lock gears in place, for strength and for safety. Once a worm gear turns the spur gear, the spur gear stays!

Can you figure out why these objects use worm gears? If you realized that the worm gear allows these devices to lock, you would be correct. The guitar strings cannot pull against the worm gear and lose their tuning. Likewise, the jaws of the crescent wrench are locked in position because they cannot move the worm gear.

Try This

First: Turn the handle that rotates the worm gear and observe how the worm gear spins. Watch how the spirals around the worm gear pull on the teeth of the spur gear.

Second: Turn the handle that rotates the spur gear. Observe how the spur gear will not move.â&#x20AC;&#x2C6;Pay special attention to how the teeth of the spur gear press against the sides of the spirals of the worm gear but cannot make it rotate.

v021314

Project

COMPLEX MACHINE

Engineering

Workshop Vice

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 1)

Building Block 15 with Bore (Qty 8)

Locking Worm m=1.5 (Qty 1)

Clip 5 (Qty 1)

Building Block 15 (Qty 1)

Bearing Sleeve (Qty 1)

Clip Axle 45 (Qty 1)

Worm m=1.5 (Qty 1)

Crank Shaft (Qty 1)

Building Block 7.5 (Qty 4)

Building Block 15 with 2 Pins (Qty 4)

Clip Axle 90 (Qty 2)

Clip Axle 75 (Qty 1)

Hub Nut Worm (Qty 1)

Angle Block 30 (Qty 4)

Worm Nut m=1.5 (Qty 1)

Mounting Plate 15x45 (Qty 2)

Link 15 (Qty 2)

Angle Block 60 (Qty 4)

Base Plate 120x60 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

2 1

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order.

The assembly should look like this before proceeding to the next step.

All steps have an “exploded view” which helps with assembly. x1

Shown in actual color.

3 2

15 x2

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Second

Third

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Fifth

3 4

From Step 1

5 4

Sixth

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2 5

3 6

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Sixth

4 7 From Step 5

5 8 45

45 x1 Rotate to tighten the Hub Nut Worm. x1

2 9 Rotate the entire assembly to insert it into the Worm Nut m=1.5. From Step 7

3 10

Orient the model as shown. Insert the axle into the Building Block 15 with Bore on the side without the Link 15s.

From Step 4

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4 11

Third

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Sixth

Hold the Worm m=1.5 gear in place while inserting the Clip Axle 75.

Be sure the Worm m=1.5 and Locking Worm m=1.5 line up. The two worm gears should appear as one.

5 12 90

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2 13

30 x4

60 x4

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From Step 12

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2 15

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Finished Model

Caution: The worm gear can create enough force to split the model apart or break it. Be careful not to overextend or overtighten the vice.

Engineering A simple machine is a device that has one function, a minimum of moving parts, and makes work seem easier by overcoming resistance, such as gravity or friction.

Lever

Often, multiple simple machines are used together to create a complex machine. A complex machine is a device made out of two or more simple machines that work together to make a task seem easier.

How has it changed the world? Workshop vices are commonly used to hold objects still so they can be worked on. Since a vice uses a worm gear, the vice can be quickly and easily tightened to clamp down on an object so strongly that the object cannot move. Imagine trying to use a saw on a piece of metal pipe, a grinder on a piece of steel, or drilling a perfectly straight hole through a block of wood if you had to hold it still with your hand!

A workshop vice is a complex machine because it combines two simple machines. A vice uses a screw (worm gear) to pull the two halves together, and a lever to turn the screw. Because the worm gear must rotate to move the two jaws of the vice, turning the lever is the only way to grip and release the jaws. The jaws of the vice will break before the worm gear will turn on its own and release the viceâ&#x20AC;&#x2122;s grip. A workshop vice is a strong device. Even a fraction of a turn on the lever will cause the grip of the vice to be permanently tighter!

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Try This

Jaws

Lever

Worm Nut Worm Gear

1. Open the jaws of the workshop vice until there is a gap between them. 2. Gently pull on the jaws of the vice and note what happens. Can you move them? 3. Turn the lever of the vice and note how easily the jaws of the vice move back and forth. 4. Pay special attention to how the worm gear moves through the worm nut during both tests.

v021314

Project

WHEELS

Engineering Each step is color coded in order of assembly.

Cart Launcher

First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 16)

Building Block 15 with 2 Pins (Qty 2)

Building Block 15 with Bore (Qty 11)

Building Block 5 (Qty 8)

Clip (Qty 2)

Link 15 (Qty 4)

Flat Hub Collet (Qty 4) Building Block 7.5 (Qty 3)

Building Block 15x30x5 with 3 Grooves (Qty 1)

Angular Block 10x15x15 (Qty 2)

Rubber Band (Qty 1)

Tire 45 (Qty 4)

Hub Nut (Qty 4)

Mounting Plate 15x60 (Qty 1)

Mounting Plate 15x45 (Qty 1)

Spacer Ring (Qty 4)

Clip Axle 30 (Qty 2)

Clip Axle 60 (Qty 2)

Base Plate 120x60 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

2 1

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order.

The assembly should look like this before proceeding to the next step. x8

All steps have an “exploded view” which helps with assembly. Place two of the assemblies aside until Step 3. Shown in actual color.

3 2 15

15 x4

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4 3 From Step 1

Note the location of the pins.

5 4 Be sure the holes on the Building Block 15s with Bore line up. x4

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2 5 Be sure the holes on the Building Block 15s with Bore line up.

Set one aside to use as a sled in the Try This challenge.

3 6 60

From Step 5

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Fifth

7 4 x2

Once positioned on the axle, tighten the Hub Nuts until they can no longer turn freely on the axle.

5 8 x2

Once positioned on the axle, tighten the Hub Nuts until they can no longer turn freely on the axle.

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3 10 x2

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2 13 30 x2

3 14

Slot 4

From Step 11

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4 15

5 16

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2 17

Slide the two Clip Axle 30s through the two Building Block 15s with Bore. The assembly will rest on top of the model.

From Step 14

3 18

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4 19

5 20

Slide the Building Block 7.5s inward slightly to lock the plunger in place. From Step 17

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2 21 x2

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4 23

Sixth

Push the rubber band through the Building Block 15 with bore. Use a spare axle to help push if necessary.

Loop both ends of the rubber band around the ends of the Cilp Axle 30s.

5 24

Use a spare axle to press the Clip Axle 30s down completely to prevent the rubber band from sliding off. Remove the spare axle when done.

Finished Model

Engineering Newtonâ&#x20AC;&#x2122;s First Law of Motion: An object in motion tends to remain in motion unless an external force is applied to it. This means that, once an object is moving, it will continue to move forever unless something stops it. On Earth, gravity is the primary force that acts on moving objects. When gravity pulls objects into each other (such as the surface of a sled into the surface of the ground), the objects rub against each other and create friction. Friction converts kinetic energy (moving energy) into heat. Because the energy that is moving the object forward is lost, the object will stop.

The cart launcher model demonstrates how wheels are used to overcome friction. When the launcher and rubber band are pulled back, they store energy. When they are released, the energy transfers from the launcher to the cart. When the cart with wheels is launched, there is little friction between the wheels of the cart and the ground, and the energy continues to move the cart forward. However, when the cart without wheels is launched, instead of the energy moving the cart forward, it is quickly lost to friction.

How has it changed the world? Nearly every type of transportation that moves across solid ground uses wheels to reduce friction. A common example of a use of the wheel is an automobile. Once a vehicle is moving, the wheels allow the body of the vehicle to move with very little friction with the surface of the road. The use of the wheel greatly reduces friction because it can roll. When friction pulls on the surface of the wheel, the wheel will rotate, moving the surface out of the way and introducing a new surface. Because the surface of the wheel in contact with the ground is constantly changing, there is very little friction, and very little kinetic energy is lost. This allows objects that roll to move much farther than objects that do not. The braking system in a car demonstrates this. Brakes prevent the wheels from rotating, which greatly increases the friction between the wheel and the road, causing the vehicle to stop.

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Try This Use a separate sheet of paper to answer the following questions.

1. Hold the launcher in place. 2. Draw back the launch arm until it touches the Mounting Plate 15x60.

3. Place the sled flush against the launcher and let the launch arm go. The launch arm should snap forward and push the sled. 4. Observe the distance the sled travels.

3. Place the cart flush against the launcher and let the launch arm go. The launch arm should snap forward and push the cart. 4. Observe the distance the cart travels.

Try launching the cart and sled on several different surfaces and observe the distances traveled.

Examples of different surfaces: Low Friction: A glass top or polished wood table or desk. Moderate Friction: Dense carpet. High Friction: Crumbled paper taped to a desk.

v021314

Project

GEAR TRAINS

Engineering Each step is color coded in order of assembly.

Souped-Up Cruiser

First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 4)

Flat Hub Collet (Qty 7)

Gear Wheel T20 (Qty 3)

Building Block 15 (Qty 2)

Hub Nut (Qty 7)

Link 15 (Qty 3)

Building Block 15 with Bore (Qty 8)

Clip Axle with Gear Teeth T28 (Qty 1)

Link 30 (Qty 1)

Clip 5 (Qty 4)

Building Block 7.5 (Qty 6)

Mini Motor 6-9v (Qty 1)

Sleeve 15 (Qty 4)

Motor Reducing Gearbox (Qty 1)

Cog Wheel T10 Narrow (Qty 3)

Clip Axle 30 (Qty 2)

Tire 45 (Qty 4)

Metal Axle 125 (Qty 2)

Clip Axle 45 (Qty 2)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

Third

2 1

Fourth

Fifth

Sixth

Parts shown in color-coded building order. 45

All steps have an “exploded view” which helps with assembly. x2 45

x2 30

x2 Shown in actual color.

3 2

The assembly should look like this before proceeding to the next step.

Place one of the assemblies aside until Step 3.

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle.

x1 Assembly A

First

Second

4 3

Third

Fourth

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Sixth

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle.

x1 The Flat Hub Collet and Hub Nut must face the opposite direction as they did in step 2. x1 From Step 1

Assembly B

5 4

x2 Assembly B

Assembly A

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2 5

Second

Third

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Fifth

Sixth

Note the position of the gears on Assembly A and B. The Gear Wheel T20s must be on opposite ends.

The gears must line up as shown. Adjust as necessary.

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Second

6 4

Fourth

Fifth

Sixth

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle.

ta Me

Third

ta Me

5 7 x2

Hold the Building Block 15s with Bore in place while proceeding to the next step.

Position the Gear Wheel T20 so that it is slightly offset of center.

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8 2 From Step 5

The gears must line up as shown. Adjust as necessary.

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9 2 x2

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle.

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2 12 5

l 12

ta Me

3 13

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle. x2 tal

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2 14 Use the Building Block 7.5s to connect the two halves of the car.

Note the position of the Link 30 and which side of the vehicle it is on.

From Step 13

Note the position of the gears and which side of the vehicle they are on.

From Step 9

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2 15

Press the gearbox onto the motor until the gears mesh and cannot move. x1

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2 16

From Step 14

Slide the motor onto the Link 30. Gently push the motor forward until the teeth of the gears mesh. Do not force the motor too far forward or the gears will bind.

PCS

Finished Model

1. Hook the model to a power supply and switch it on. Does the vehicle move smoothly? 2. Identify the types of gears used in this model.

Engineering must rotate four times for the output gear to make one rotation. Therefore, the gear ratio is . Engineers usually express this ratio as 4:1, read “four to one” gear ratio. 4 — 1

A gear train is a set of multiple gears arranged to translate a rotation from the input to the output. For instance, the output gear can move faster than the input gear, the output gear can move slower than the input gear, or the output gear can move the same speed as the input gear.

When the Gear Wheel T10 from the gearbox is added back into the example, the gear ratio is 6:1.

Input

Output

How has it changed the world?

The gear ratio is what determines the relationship between the input gear and the output gear. Gear ratios are formed using gear pairs. (This is why the first gear is not counted in this example.) To explore this concept, remove the engine (motor and gearbox) from the cruiser.

Many everyday objects and inventions use gear trains. Clocks, mixers, and virtually every transportation machine, whether it is a car, train, or boat contain gear trains.

The gears that remain form the gear train. Count the number of times the input gear must rotate for the output gear to rotate once. The gear ratio is expressed by the input over the output. For example, with the motor removed, the input gear

First

Second

Third

Fourth

Fifth

Sixth

Try This

Input

Output

1. With the motor disconnected from the model, turn the motor on and observe how fast the attached gear rotates on the motor. 2. Now reattach the motor to the model and turn it on. Notice how this gear train reduces the speed from the input gear (on the motor) to the output gear connected to the wheels. 3. Try rearranging the gears so the output spins faster than the input. 4. What differences do you observe?

__________________________________________________________________________________________________

v020113

Project

FLEXIBLE POWER SYSTEMS

Engineering

Flexible Systems Plane

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 15 with 2 Pins (Qty 1)

Angle Block 15 Degrees (Qty 5)

Building Block 15 with Bore (Qty 2)

Angle Block 30 Degrees (Qty 2)

Building Block 15 (Qty 7)

Building Block 5 with 2 Pins (Qty 1)

Angular Block 10x15x15 (Qty 4)

Crank Shaft (Qty 1)

Clip Axle 30 (Qty 3) Mounting Plate 15x90 (Qty 2)

Mounting Plate 30x45 (Qty 3)

Hinged Block Claw (Qty 4)

Hinged Block Tab (Qty 1)

Building Plate 15x30x5 (Qty 2)

Seat (Qty 1)

Link 15 (Qty 1)

String (Qty 1)

Axle with Clip (Qty 1)

Mounting Plate 15x45 (Qty 2) Axle Coupling (Qty 2)

Clip Adapter (Qty 1)

Base Plate 120x60 (Qty1)

0 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18

PCS

1 15

All steps have an â&#x20AC;&#x153;exploded viewâ&#x20AC;? which helps with assembly.

The assembly should look like this before proceeding to the next step.

PCS

Repeat steps one and two and construct a second assembly. This time, create it as a mirror image of the first.

PCS

9 45

PCS

10 30

Slo

PCS

Build two of the assemblies.Turn one over so they face opposite directions.

PCS

The groove must be perpendicular to base plate slots.

PCS

A B Create a second assembly that is a mirror image of the first.

PCS

B A

PCS

Thread a string through the rear Axle Coupling. Tie a knot to hold it in place when both sides of the string are equal.

Thread the ends of the string through the sets of Hinged Block claws on each side of the model.

Insert the string ends through the Axle Connector.

30 Secure the string in place with a Clip Axle 30. Center the rear Mounting Plate 30x45, and tighten the string by gently pulling on the ends.

PCS

Finished Model

PCS

Engineering Tension is the force that a stretched object exerts on its supports. It is the force pulling on the outside of an object. When the rubber band is pulled, and the rubber band stretches and becomes increasingly tight, thatâ&#x20AC;&#x2122;s tension!

Another use of flexible power systems is the ability to transmit power around bends, corners, and turns. In the case of the airplane model, this allows the power to transmit from the control lever, around the body of the plane by passing through pulleys, and transmitting the motion to the tail.

Flexible systems are systems that use tension to transmit movement or power over distance. Without tension, a flexible system is useless. To demonstrate this, hold a string between the fingers of your left and right hand. Hold the string tight enough so that the string doesnâ&#x20AC;&#x2122;t slip between your fingers. Now, move your right hand back and forth. Notice how your left hand doesnâ&#x20AC;&#x2122;t do anything when the string has slack in it, but when the string is tight, your left hand moves with the string.

An example would be a string hanging from a light on the ceiling that is out of reach. When you pull on the string, you apply tension. That tension transmits through the string and pulls the switch on the light, turning it off and on.

PCS

How has it changed the world? Many different inventions and devices use flexible systems to transmit power. Airplanes, boats, cars, bicycles, and many other types of transportation use flexible systems to transmit power from the operator to the vehicle. An example would be the brakes on your bicycle. When you press on the brakes, a cable transmits power to the brakes on your tires.

Try This Flexible power systems allow power to be transmitted at an angle. In the case of the airplane model, this allows the transmitted power to pull on the tail of the plane from the sides. The transmitted power must pull on the sides of the tail for it to be able to swivel to the left and right. If the power were pulled in a straight line from the front, the tail wouldnâ&#x20AC;&#x2122;t turn.

Try modifying the model to transmit the power from the lever to the tail, but transmit the power in a straight line. (You may need to use a Building Block 15 with Bore under the driverâ&#x20AC;&#x2122;s seat to allow the string to be connected in a straight line.) Note how the tail operates between the original and the new setup.

PCS

v021314

Project

SPEED RATIOS

Engineering

High Speed Fan

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 4)

Hub Nut (Qty 2)

Spring Cam (Qty 2)

Building Block 15 with Bore (Qty 7)

Flat Hub Collet (Qty 2)

Cog Wheel T10 Narrow (Qty 2)

Building Block 15 with 2 Pins (Qty 4)

Clip Axle 30 (Qty 1)

Crank Shaft (Qty 1)

Building Block 15 (Qty 2)

Clip Axle 45 (Qty 4)

Gear Wheel T30 (Qty 2)

Building Block 7.5 (Qty 2)

Clip 5 (Qty 2)

Bearing Sleeve (Qty 1)

Mounting Plate 30x45 (Qty 2)

Angle Block 15 (Qty 2)

Sleeve 15 (Qty 2)

Base Plate 120x60 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

Third

Slot

Fifth

Sixth

Parts shown in color-coded building order.

All steps have an “exploded view” which helps with assembly.

Fourth

Slot

Shown in actual color.

The assembly should look like this before proceeding to the next step.

First

Second

Third

Fourth

Fifth

Sixth

The grooves along the tops of all three Building Blocks must line up.

First

Second

Third

Fourth

Fifth

Sixth

2 3

x2 Slot

4 3

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle.

45 x1

First

Second

Third

Fourth

Fifth

5 4 x1

From Step 3

5 6 x2

Sixth

First

Second

Third

Fourth

Fifth

Sixth

2 7 45 x1

45 x1

Once positioned on the axle, tighten the Hub Nut until it can no longer turn freely on the axle.

First

Second

Third

Fourth

Fifth

2 8 x1

From Step 6

Sixth

First

Second

Third

Fourth

Fifth

Sixth

2 9

From Step 5 Be sure the teeth of the gears mesh. Adjust the model if necessary.

First

Second

Third

Fourth

Fifth

10 x2

Sixth

First

Second

2 11

Third

Fourth

Fifth

Sixth

Be sure the Clip Axle 30 clips into the Cog Wheel T10 Narrow on the other side of the Building Block 15 with Bore. 30

x1 30

3 12

45 x1

Be sure the teeth of the gears mesh. Adjust the model if necessary.

First

Second

Third

Fourth

Fifth

4 13 x1

5 14 x1

Sixth

First

Second

Third

Fourth

Fifth

Sixth

The Angle Block 15s must face opposite directions. This gives the fan blades different angles. x2

Do not slide the Mounting Plate 30x45s past the inner edges of the Angle Block 15s.

First

Second

Third

Fourth

Fifth

Sixth

16 45

45 x1

From Step 13

Finished Model

Engineering A fan is a machine that is used to create air flow. The blades (or vanes) of the fan are inclined to move the air. If the blades were flat, the air would not be pushed and would barely move. Think about the shape of the blades that you see on a cooling fan.

The fan in this build uses a gear train to create a speed ratio. This means that the system output, the fan, turns faster than the input crank. Imagine if there wasn’t a speed ratio, and you had to turn the crank as fast as you wanted the fan to spin!

Pushes Air

The direction of rotation determines whether the fan is pushing or pulling air. In fact, an aircraft propeller is a fan that pulls air, essentially pulling the aircraft through the atmosphere. The same concept is true with the propellers of ships, except they usually push the ship through water by pulling water through the propeller.

How has it changed the world? Fans are used every day in a variety of machines throughout the home. Mostly, they are used to cool certain parts of appliances such as a microwave oven. The fan in the microwave keeps the generator from overheating. If the generator overheats, it burns out and no longer works. Other common uses of the fan are found in leaf blowers, hair dryers, desktop computers, and vacuum cleaners.

Pulls Air

Try This

Blades

1. What happens when you switch out the Angle Block 15s on the fan blades for different blocks?

Angle Block 15s

Try different blocks from a Building Block 5 (0°) to an Angle Block 60.

Building Block 5

Angle Block 7.5

Angle Block 30

Angle Block 60

__________________________________________________________________________________________________

2. Which angle produces the most wind? __________ 3. Which angle produces the least? __________ 4. Can you feel a difference when turning the crank while using each angle block? __________

v021314

Project

POWER RATIOS

Engineering Each step is color coded in order of assembly.

Power Winch

First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 2)

Spacer Ring (Qty 2)

Building Block 15 with Bore (Qty 8)

Axle Coupling (Qty 1)

Gear Wheel T20 (Qty 3)

Bearing Sleeve (Qty 1)

Cog Wheel T10 Narrow (Qty 3)

Building Block 15 (Qty 8)

Flat Hub Collet (Qty 3)

Clip Axle 30 (Qty 2)

Building Block 7.5 (Qty 8)

Hub Nut (Qty 3)

Clip Axle 45 (Qty 4)

Clip 5 (Qty 5)

Spring Cam (Qty 6)

Crank Shaft (Qty 1)

String (Qty 1)

Clip Axle 75 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

All steps have an “exploded view” which helps with assembly.

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order.

Shown in actual color.

The assembly should look like this before proceeding to the next step.

3 2 x2

First

Second

Third

Fourth

Fifth

Sixth

4 3 45 45

Once positioned on the axle, tighten the Hub Nut until it can no lnger turn freely on the axle.

5 4 x1 From Step 2

45 x1

First

Second

Third

Fourth

Fifth

Sixth

2 5 30

6 3 45

45 x1

First

Second

Third

Fourth

Fifth

Sixth

7 x2

From Step 4

Assembly A Set the assembly aside until Step 17.

First

Second

Third

Fourth

Fifth

Sixth

2 8 x2

9 3

75 x1

Once positioned on the axle, tighten the Hub Nut until it can no lnger turn freely on the axle.

First

Second

Third

Fourth

Fifth

4 10 x1

5 11 x1

Sixth

First

Second

Third

Fourth

Fifth

Sixth

12 x2

From Step 8

First

Second

Third

Fourth

Fifth

Sixth

13 45 x1

Once positioned on the axle, tighten the Hub Nuts until it can no lnger turn freely on the axle.

5 14 x1

First

Second

Third

Fourth

Fifth

Sixth

15 x1

3 16 Be sure the gears mesh. Adjust the positioning of the gears if necessary.

From Step 12

Assembly B

First

Second

Third

Fourth

Fifth

Sixth

Attach the two halves of the winch by securing the Building Block 7.5 onto the pins of the Building Block 15s in each corner. x2

From Step 7

A B

Underside View

Be sure the two halves are aligned so that the Gear Wheel T20 and the Cog Wheel T10 Narrow are on the same side.

First

Second

Third

Fourth

Fifth

Sixth

18 x4

Insert the Spring Cams first. Once the Spring Cams are in place, slide the Building Block 7.5s into the slots.

First

Second

Third

Fourth

Fifth

19 x1

Pull the Clip Axle 45 out of the Axle Coupling and insert the string. Reinsert the Clip Axle 45 and tie or tape the string in place. Turn the Crank Handle to wind up the string.

Sixth

Finished Model

Input

1. Rotate the input Crank Shaft. Does the output turn? 2. How many times do you have to turn the input to make the output turn once?

Engineering In the case of a winch, torque is desired because torque increases strength and decreases speed. Oftentimes, when pulling something with a winch, speed can be a bad thing; it can cause lack of control, which can lead to damage or injury.

A winch is a hauling or lifting machine consisting of a rope or chain winding around a horizontal rotating drum usually turned by a crank or motor. It is essentially a lever combined with a wheel and axle, but in this case, the rotating drum is usually referred to as a spool. The spool provides a place for the cable to be coiled, and the lever makes it easier to move the load. In modern times, instead of a lever, a motor is used to drive the winch. Also, a gear train may be added to provide additional mechanical advantage.

How has it changed the world? A winch can be found in many devices and large-scale machines. Tow trucks use them to pull out cars that are stuck. Large ships use a winch to lower and raise their massive anchors; imagine a crew of a large ship trying to lift a 100,000 pound anchor without help! Also, tall buildings use winches to raise and lower their elevators.

A gear train is comprised of two or more gears that drive one another. The first gear is considered the input and the last gear is the output. They are used to transmit rotary motion and increase either speed or torque from the input to the output.

Try This

Input

Output

1. How many times do you have to turn the input lever to make the output turn once?â&#x20AC;&#x201A; ____________________ 2. Lift or pull an object from the classroom (such as an eraser or a stapler) using the winch. 3. Now, switch the input and the output by placing the Crank Shaft onto the Clip Axle 45 on the output and move the string to the input axle. (See picture) 4. Pull the same object again and note the difference. Was it easier or more difficult? Why?

____________________________________________

v021314

Project

#10

POWER TRANSFER

Engineering

Universal Joint

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 8)

Building Block 15 with Bore (Qty 10)

Angle Block 10x15x15 (Qty 4)

Angle Block 60 (Qty 1)

Link 15 (Qty 3)

Building Block 15 (Qty 5)

Building Block 15 with 2 pins (Qty 2)

Axle with Clip (Qty 4)

Bearing Sleeve (Qty 1)

Crank Shaft (Qty 1)

Clip Adapter (Qty 3)

Clip Axle 30 (Qty 2)

Base Plate 120x60 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order. 60

The assembly should look like this before proceeding to the next step.

All steps have an “exploded view” which helps with assembly.

Shown in actual color.

3 2

First

Second

Third

Fourth

Fifth

4 3 Attach the assembly to the exterior pin of the Angle Block 60.

From Step 1

5 4

Sixth

First

2 5

Second

Third

Fourth

Fifth

Sixth

30 x1

3 6 x2

First

Second

Third

Fourth

Fifth

2 7

Sixth

First

Second

Third

Fourth

Fifth

Sixth

2 8 x4

3 9 x2

15 x2

First

Second

2 10

Third

Fourth

Fifth

The groove on the Building Block 15 must be horizontal.

Place one of the assemblies aside until Step 12.

Sixth

First

Second

Third

Fourth

Fifth

Sixth

2 11

From Step 8

3 12

From Step 10

First

Second

Third

Fourth

Fifth

Sixth

From Step 5

5 14

30 x1

15 x1

Adjust the universal joint assembly to allow the axle to fit.

Finished Model

Output

Input

1. Turn the input crank shaft. Does the universal joint turn smoothly? 2. Experiment with the output shaft. Move the output shaft in different locations. Does the output shaft continue to rotate at different angles?

Engineering road. If the angle between the shaft and the axle could not change, the car would be extremely rigid (causing every bump to be felt as it travels down the road), rotational motion would not transfer to the wheels, or the system could break under stress.

How has it changed the world?

The basic universal joint (u-joint) consists of two, letter â&#x20AC;&#x153;Uâ&#x20AC;? shaped yokes connected to each other with a shaft connected to each yoke. There is a cross-shaped part that holds the yokes together and enables each yoke to pivot in relation to the other. One shaft can drive the other even though they are resting at different angles. Also, the u-joint enables the angle between the two shafts to consistently change while rotating.

U-joints provide an efficient way to route rotational movement through a complex machine, because the input and output do not need to be in a straight line. The universal joint can also flex and move during operation, allowing for rotational motion to be transferred at varying angles up to 89 degrees.

Without universal joints most complex machines would be much more rigid in their designs. Complicated and non-flexible gear trains would be required to change the angle between the input and output. Universal joints offer a simple and reliable means of changing the angle of rotation, allowing machines to be more efficient and capable. Shafts are often used to transmit rotary power in a machine. A universal joint connects axle shafts and systems that provide power. They allow power to be transmitted from the input to the output through various angles. In most cars, a universal joint is necessary because the angle between the engine and the wheels is constantly changing as the wheels of the car move up and down over bumps in the

Try This Experiment with your model. Disconnect the arm that holds the output end of the universal joint in place. Move the output shaft to new angles relative to the input. â&#x20AC;&#x2C6;

Input

Output

1. Can you feel a difference in the rotation? Universal joints have a limited range of angles in which they can operate without binding. 2. Can the universal joint transmit rotational motion at 90 degrees? Explain your findings.

__________________________________________________________________________________________________

v062514

Project

DRIVE TRAIN

#11

Engineering

Mixer

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 16)

Building Block 5 (Qty 3)

Flat Hub Collet (Qty 1)

Hinged Block Claw (Qty 4)

Building Block 15 (Qty13)

Building Block 15 with Bore (Qty 7)

Base Plate 120x60 (Qty 1)

Building Block v15 Corner (Qty 2)

Building Block 7.5 (Qty 2)

Building Block 15 with 2 Pins (Qty 1)

Hub Nut (Qty 1)

Spring Cam (Qty 9)

Crank Shaft (Qty 1)

Mounting Plate 15x15 (Qty 1)

Mounting Plate 15x60 (Qty 2)

Axle with Clip (Qty 2)

Clip Adapter (Qty 2)

Bearing Sleeve (Qty 5)

Cog Wheel T10 Narrow (Qty 4)

Clip Axle 30 (Qty 4)

Intertoothed Gear T30 (Qty 1)

Gear Wheel T30 (Qty 1)

Axle Coupling (Qty 1)

Wheel Axle with Bevel Gear (Qty 2)

Clip Axle 45 (Qty 1)

Bevel Gear with Sleeve (Qty 1)

Clip 5 (Qty 3)

Chain Link (Qty 42)

Link 15 (Qty 2)

Clip Axle 75 (Qty 1)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

All steps have an “exploded view” which helps with assembly.

2 1

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order.

Shown in actual color.

The assembly should look like this before proceeding to the next step.

Place two of the assemblies aside until Step 3.

3 2

The grooves on the tops of the Building Block 30s must be oriented as shown.

x1 t2

Slo

First

Second

Third

3 4

Fourth

Fifth

The grooves on the tops of the Building Block 30s must be oriented as shown.

From Step 1

Slot

From Step 1

4 5

Once positioned on the center of the axle, tighten the Hub Nut until it can no lnger turn freely on the axle.

Sixth

First

Second

Third

Fourth

Fifth

Sixth

2 5 x2

First

Second

Third

Fourth

Fifth

Sixth

6 4 30

45 x1

30 x1

7 5 x1

From Step 5

First

Second

Third

Fourth

Fifth

Sixth

2 8

3 9

From Step 7

first

second

third

fourth

fifth

sixth

10 2 Crank Handle side

3 11 x1

Center all the parts on the model.

First

Second

Third

Fourth

Fifth

Sixth

2 12 x3

3 13 x2

First

Second

Third

Fourth

Fifth

4 14 x2

5 15 x1

Sixth

First

Second

Third

Fourth

Fifth

Sixth

2 16 x1

3 17 The teeth of the bevel gears must mesh and rotate smoothly.

From Step 15

First

Second

Third

Fourth

Fifth

4 18 x2

5 19

Hinged Block Claws and Bearing Sleeves may already be assembled from previous models. x1

From Step 4

Sixth

first

second

third

fourth

fifth

sixth

20 2

Slide the entire assembly onto the Spring Cam.

From Step 11

First

Second

Third

Fourth

Fifth

Sixth

21 2 Clip all 42 chain links together to form a long strand. x42

Wrap the chan link strand around the lower gear and upper gear, bringing the ends together at the top. Snap the ends of the chain link together.

First

Second

Third

Fourth

Fifth

Sixth

2 22 x2

3 23 x1

First

Second

Third

Fourth

Fifth

4 24

Sixth

Hinged Block Claws and Bearing Sleeves may already be assembled from previous models. x2 30 x2

5 25

From Step 23

First

Second

Third

Fourth

Fifth

Sixth

2 26

From Step 22

First

Second

Third

Fourth

Fifth

15 x2

5 28

From Step 26

Sixth

Finished Model

1. Turn the input (handle lever) and observe the mixer. Identify the output ratio for the model. 2. Identify each component that transfers power in this machine.â&#x20AC;&#x2C6;

Engineering The mixer model is an example of a complex machine. A complex machine is composed of many different simple machines working together. This mixer model integrates levers, gears, and gear pairs to create a new system.

Upper Drive Shaft Bevel Gears

Chain Drive

Planetary Gears

Output: Mixing Paddles

Input: Lever

Lower Drive Shaft

The mixer incorporates a drive train. A drive train brings together several types of drive components, such as chain drives, bevel gears, and gear trains to transfer rotational power from the input to the output. The drive train in the mixer model integrates several of these elements together into one machine that is designed to mix ingredients, such as flour and water into dough.

Try This Follow the drive train on the model from the input lever to the output paddles.

4. The bevel gear pair is unique because it changes the axis of rotation by 90 degrees.

3. The drive shaft transfers rotary power from the chain drive to the bevel gear pair.

2. The next element is a chain drive which consists of two gears and an interconnecting chain. In this case, the chain drive accomplishes two things: • Transfers power over a distance from the lower drive shaft to the upper drive shaft. • Provides a torque increase.

5. The bevel gear drives a planetary gear set. Study this gear set as you turn the input crank. Notice how it transfers rotational power to the two axles and also allows the axles to rotate about the central axis. It is called a “planetary” gear set because the outer gears “orbit” the inner gear in the same way that planets orbit the sun.

Input

Output 6. Finally, these two axles hold the paddles, which transfer the rotational power to the mixture (such as dough).

1. The drive train begins with the input crank shaft, which is a lever that rotates around a shaft. It transfers power from a person to the mixer’s drive train.

v021314

Project

POWER TRANSFER

#12

Engineering

Three Gear Transmission

Each step is color coded in order of assembly. First Second Third Fourth Fifth Sixth

Icon Legend Set assembly aside.

Build the number shown. Rotate assembly.

Flip assembly.

Materials you will need:

Building Block 30 (Qty 9)

Collet Chuck (Qty 1)

Flat Hub Collet (Qty 4)

Building Block 15 (Qty 2)

Building Block 5 (Qty 1)

Hub Nut (Qty 4)

Building Block 15 with 2 Pins (Qty 5)

Building Block 15x30x5 with Groove and Pin (Qty 5)

Axle Coupling (Qty 2)

Building Block 15 with Bore (Qty 7)

Building Block 7.5 (Qty 12)

Spring Cam (Qty 10)

Clip 5 (Qty 3)

Clip Adapter (Qty 2)

Worm m=1.5 (Qty 1)

Mounting Plate 15x45 (Qty 3)

Cog Wheel T10 Narrow (Qty 2)

Mounting Plate 15x15 (Qty 4)

Clip Axle with Gear Teeth T28 (Qty 1)

Locking Worm m=1.5 (Qty 1)

Link 30 (Qty 3)

Mini Motor 6–9v (Qty 1)

Hub Nut Worm (Qty 2)

Building Plate 15x45 with 2x2 Pin (Qty 1)

Motor Reducing Gearbox (Qty 1)

Gear Wheel T15 Gear Wheel T20 (Qty 1) (Qty 2)

Clip Axle 30 (Qty 7)

Clip Axle 60 (Qty 2)

Clip Axle 75 (Qty 2)

Clip Axle 90 (Qty 2)

Gear Wheel T30 (Qty 2)

Mounting Plate 15x90 (Qty 2)

Base Plate 120x60 (Qty 2)

0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150 160 170 180 (mm)

First

Second

Third

Fourth

Fifth

Sixth

Parts shown in color-coded building order.

2 1

All steps have an “exploded view” which helps with assembly.

Shown in actual color.

The assembly should look like this before proceeding to the next step.

First

Second

Third

Fourth

Fifth

Sixth

2 4 x2

Slot

x1 The direction of the pins on the underside of the Building Block 15x30x5 with Groove and Pin is unimportant.

3 5 x2

Both of the center grooves on the Building Block 30s must be horizontal as shown.

First

Second

Third

Fourth

Fifth

Sixth

2 4 30 x1

3 5

Press the gearbox onto the motor until the gears mesh and cannot move.

First

Second

Third

Fourth

Fifth

Sixth

2 6 30

30 x1

From Step 4

Slide the motor far enough onto the Link 30 to align the hole in the Motor Reducing Gearbox with the Axle Coupling.

First

Second

2 7

Third

Fourth

Fifth

Sixth

Press the Clip Axle with Gear Teeth T28 through the Motor Reducing Gearbox until it clips into the Axle Coupling.

30 x1

3 8 90

Place the gear assembly approximately one-third of the way along the Clip Axle 90.

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9 4 x1

5 10 x1

From Step 7

Sixth

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Sixth

2 11 x2

3 12 x4

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4 13

5 14 x1

Sixth

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2 15 x1

Rest the assembly on top of the Building Block 30s and hold it in place.

From Step 10

Slide the Building Block 7.5 onto the Link 30 and the inner pin of the Building Plate 15x45 with 2x2 Pin.

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4 16 30

60 x1

5 17 75 x1

Sixth

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2 18

From Step 16

All of the gears must be aligned as shown. Loosen the Hub Nuts and adjust the position of the gears as necessary. Retighten once adjustment is complete.

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4 19 x2

5 20

From Step 18

The lower pin of the Building Block 15 will not touch the Base Plate 120x60.

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2 21 x2

Slide the Building Block 15x30x5s with Groove and Pin underneath the Building Block 15.

3 22 x1

The Building Block 15x30x5 with Groove and Pin will hang over the edge slightly.

x1 Be sure the pin on the Building Block 15x30x5 with Groove and Pin is facing towards the Base Plate 120x60.

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4 23 75 x1

75 x1

5 24

30 x1

From Step 22

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2 25 x2

Slide both Spring Cams to the very center before adding the Building Block 7.5 and Building Block 30.

3 26 90

Only tighten the Hub Nut Worm after all other parts are in place.

90 x1

x1 60

x1 x1

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4 27

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Sixth

Slide the assembly from Step 26 through the Building Block 15 with Bore and clip into the Cog Wheel T10.

Be sure the teeth on the Worm m=1.5 and Gear Wheel T15 mesh.

x1 From Step 25

5 28 x1

Finished Model Input Gear Shift

Output

1. Connect the motor to a power supply and switch it on. Does the transmission output rotate? 2. Experiment with moving the gear shift and changing the gear pairs. Is the output speed affected by different gear pairs in the system?

Engineering This means an engine has a small RPM range where it is the strongest and most useful. A transmission allows for that useful range in an engine’s power to be accessed multiple times without overworking the engine. Once the engine no longer has the strength to increase the output speed, a transmission allows the engine’s RPMs to change, or shift, so the strongest and more useful RPM range can be used again, while the output speed remains the same. Then, the speed can continue to increase without straining, over- revving, or damaging the engine.

A transmission is a device designed to transfer rotational power from a motor to a load, such as the wheels of an automobile. It uses gears that can be combined in different orders to control the difference between the input and output speeds. In automobiles, transmissions are necessary to convert the speed of the motor to the desired speed of the wheels. For example, a typical car engine operates at a range between 600 to 6000 RPM (Revolutions Per Minute), and a car’s wheels rotate between 0 and 2500 RPM.

How has it changed the world? Many bicycles have multiple gears. On a bicycle, you are the input and the wheels are the output, while the gears are the transmission. When you shift gears, you change how many times you have to pedal to turn the wheels. Some gears allow you to pedal very quickly and easily, but you don’t go very fast. Others require more strength, but allow for a lot of speed!

A typical engine has a range in its RPM band where it is the strongest. Normally, an engine does not have very much strength at low RPMs (600 to 1500) and runs out of power at high RPMs (4500 to 6000).

Try This Gear 1: Output

Move the lever all the way to the left and turn on the motor. Take note of which gear pair is engaged. The large gear is driving the small gear. Because a larger gear is driving a smaller gear, the output turns much faster than the input.

Input

Gear 2:

Output

Move the lever to the center and turn on the motor. Notice that the engaged gears are the same size. This means that the output turns at the same speed as the input.

Input

Output

Gear 3: Move the lever all the way to the right and turn on the motor. The small gear is driving the larger gear and the output speed is slower than the input speed.

Input