Power Input From the Transmission
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| Illustration 1 | g00643217 |
Input from the transmission for forward straight line operation (2) Center axle shaft (3) Bevel gear (4) Planetary gear set (5) Carrier (6) Sun gear (7) Right outer axle shaft (8) Carrier (9) Ring gear (10) Bevel gear shaft (11) Support (12) Sun gear (13) Sun gear (14) Left outer axle shaft (15) Carrier (16) Planetary gears (steering) (17) Carrier (18) Planetary gears (drive) (19) Ring gear (20) Ring gear | |
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| Illustration 2 | g00495357 |
Differential steer unit (1) Transmission pinion | |
Power from the transmission flows through transmission pinion (1) to bevel gear (3) .
Bevel gear (3) sends the power through bevel gear shaft (10) to carrier (17). Power from carrier (17) flows in two directions.
Half of the power is sent through planetary gears (18) to ring gear (20). This power is a lower speed and higher torque.
The other half of the power which is a higher speed and lower torque is sent through planetary gears (18) to sun gear (12).
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| Illustration 3 | g00495873 |
Rotation of components during forward straight line operation (1) Transmission pinion (2) Center axle shaft (3) Bevel gear (4) Planetary gear set (5) Carrier (6) Sun gear (7) Right outer axle shaft (9) Ring gear (12) Sun gear (13) Sun gear (14) Left outer axle shaft (15) Carrier (16) Planetary gears (steering) (17) Carrier (18) Planetary gears (drive) (19) Ring gear (20) Ring gear | |
Ring gear (20) sends power through carrier (15) to left outer axle shaft (14). Sun gear (12) sends power through center axle (2) to sun gear (6) .
The input from sun gear (6) is a higher speed and lower torque. This input is converted to a lower speed and a higher torque by the following components: planetary gears (4), carrier (5) and ring gear (9). Next, the output is sent through carrier (5) to right outer axle shaft (7).
Both of the outer axle shafts have the same power. Also, both of the outer axle shafts have the same rotational direction. Therefore, the machine moves straight in the forward direction or the machine moves straight in the rearward direction.
Steering Power Flow
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| Illustration 4 | g00643282 |
Counterrotation in the counterclockwise direction with power input from the steering motor only (2) Center axle shaft (3) Bevel gear (4) Planetary gear set (5) Carrier (6) Sun gear (7) Right outer axle shaft (8) Carrier (9) Ring gear (10) Bevel gear shaft (11) Support (12) Sun gear (13) Sun gear (14) Left outer axle shaft (15) Carrier (16) Planetary gears (steering) (17) Carrier (18) Planetary gears (drive) (19) Ring gear (20) Ring gear | |
When the transmission is in the NEUTRAL position and the parking brake is engaged, the power input from the steering motor flows through ring gear (19) .
The power input from ring gear (19) divides in two directions.
Half of the power is sent through planetary gears (steering) (16) to carrier (15). This power is a lower speed and higher torque. Power from carrier (15) flows to the left outer axle shaft (14) .
The other half of the power which is a higher speed and lower torque is sent through planetary gears (steering) (16) to sun gear (13).
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| Illustration 5 | g00495915 |
Rotation of components during a counterclockwise counterrotation (1) Transmission pinion (2) Center axle shaft (3) Bevel gear (4) Planetary gear set (6) Sun gear (7) Right outer axle shaft (9) Ring gear (12) Sun gear (13) Sun gear (14) Left outer axle shaft (15) Carrier (16) Planetary gears (steering) (17) Carrier (18) Planetary gears (drive) (19) Ring gear (20) Ring gear | |
Sun gear (13) sends the power through center axle shaft (2) to sun gear (6) .
The input from sun gear (6) is a higher speed and lower torque. This input from sun gear (6) is converted by the following components to a lower speed and a higher torque: planetary gears (4), carrier (5) and ring gear (9). The output is sent through carrier (5) to right outer axle shaft (7) .
Both of the outer axle shafts have the same power. However, the direction of shaft rotation is opposite. Therefore, the machine counterrotates.
Steering Power Flow And Transmission Power Flow Combined
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| Illustration 6 | g00643287 |
Forward left turn with steering input and transmission input (2) Center axle shaft (3) Bevel gear (4) Planetary gear set (5) Carrier (6) Sun gear (7) Right outer axle shaft (8) Carrier (9) Ring gear (10) Bevel gear shaft (11) Support (12) Sun gear (13) Sun gear (14) Left outer axle shaft (15) Carrier (16) Planetary gears (steering) (17) Carrier (18) Planetary gears (drive) (19) Ring gear (20) Ring gear | |
The transmission power flow is independent of the input from the steering motor. When power from both the steering motor and the transmission are applied to the differential steer unit, the power input from the transmission flows through the system as if the transmission is working individually.
The power from the steering motor is still divided. Half of the power goes in one direction and the other half of the power goes in the opposite direction.
The amount of power to one outer axle shaft is greater. This causes the speed of that shaft to increase while the speed of the other outer axle shaft decreases.
The amount of power to the axle shafts and the rotational direction is controlled by the transmission. The difference in speed between the axle shafts and the direction of the turn is controlled by the steering motor.
| Forward Left Turn | Reverse Left Turn | Forward Right Turn | Reverse Right Turn | |
| Rotation of steering motor and ring gear (19) (1) | Counterclockwise | Clockwise | Clockwise | Counterclockwise |
| Rotation of the transmission pinion (1) | Counterclockwise | Clockwise | Counterclockwise | Clockwise |
| Rotation of steering wheel | Counterclockwise | Counterclockwise | Clockwise | Clockwise |
| ( 1 ) | The rotation of the steering motor and the transmission pinion from the drive end. |
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| Illustration 7 | g00495956 |
Rotation of the components during a left forward turn (1) Transmission pinion (2) Center axle shaft (3) Bevel gear (4) Planetary gear set (5) Carrier (6) Sun gear (7) Right outer axle shaft (9) Ring gear (12) Sun gear (13) Sun gear (14) Left outer axle shaft (15) Carrier (16) Planetary gears (steering) (17) Carrier (18) Planetary gears (drive) (19) Ring gear (20) Ring gear | |
The steering direction is determined by the rotational direction of the steering motor and the rotational direction of ring gear (19). See Table 1 for more information.
The speed of the steering motor and transmission pinion (1) determine the turning radius of the machine. When the speed of the steering motor increases, the turning radius of the machine decreases.
When the machine makes a left turn, the rotation of ring gear (19) and transmission pinion (1) is the same direction.
Power to ring gear (19) flows to planetary gears (drive) (18). Planetary gears (drive) (18) send the power through sun gear (12) to center axle shaft (2). Also, power from sun gear (13) is added to center axle shaft (2) .
The combined power through center axle shaft (2) flows to sun gear (6) .
The input from sun gear (6) is a higher speed and lower torque. This input from sun gear (6) is converted by the following components to a lower speed and a higher torque: planetary gears (4), carrier (5) and ring gear (9). The output is sent through carrier (5) to right outer axle shaft (7) .
The result of lower speed and higher torque causes the rotational speed of the axle shaft to increase. This causes the speed of the opposite axle shaft to decrease an equal amount.
The speed of center axle shaft (2) increases when the power to sun gear (13) adds to the power at sun gear (12) .
The increase in power causes the speed of the sun gears to increase. When the speed of sun gear (12) increases, the speed of ring gear (19) decreases.
The reduction in speed of ring gear (19) causes a reduction in speed of carrier (15). Also, the speed of left outer axle shaft (14) decreases. The speed of right outer axle shaft (7) increases. This speed difference between the outer axle shafts permits the machine to turn to the left.
When the machine turns to the right, the rotation of ring gear (20) is opposite transmission pinion (1). Power to ring gear (20) flows through planetary gears (steering) (16) .
Power from planetary gears (steering) (16) flows to carrier (15). Also, the power from ring gear (19) is added to carrier (15) .
The combined power flows through carrier (15) to left outer axle shaft (14). This causes the following components to increase in speed: input shaft, carrier (15) and ring gear (19) .
When the speed of ring gear (19) increases, the speed of sun gear (12) decreases.
A decrease in the speed of sun gear (12) causes the following components to decrease in speed: center axle shaft (2), sun gear (6), carrier (5) and right outer axle shaft (7) .
The speed of left outer axle shaft (14) increases. The speed of right outer axle shaft (7) decreases. This speed difference between the outer axle shafts permits the machine to turn to the right.