Illustration 1 | g06156419 |
Differential and Bevel Gear Group (1) Bevel gear group (2) Differential carrier (3) Bearing cup and cone (4) Adjustment ring (5) Side gear (6) Differential group (7) Thrust washer (8) Bearings (9) Spider (10) Pinions (11) Bevel gear (12) Case (13) Side gear (14) Adjustment ring (15) Bearing cup and cone (16) Thrust washer (17) Bolt (18) Bevel pinion |
A differential divides the power that is sent to the wheels essentially balancing the power that is sent to the wheels. During a turn, the inside wheel turns at a slower rate than the outside wheel. The differential allows the inside wheel to rotate at a slower rate in relation to the outside wheel. The differential still sends the same amount of torque to each wheel.
Bevel pinion (18) is connected to a yoke assembly. The yoke assembly is connected to a universal joint from the output transfer gears. Pinion (18) is connected to the yoke assembly by splines. Pinion (18) is engaged with bevel gear (11). Bevel gear (11) is fastened to differential group (6). Differential carrier (2) is fastened to the axle housing.
Differential group (6) has a case (12). Bevel gear (11) is fastened to case (12). The case is divided into two parts, and the two parts are held together by bolts (17). The following components are inside of the case: side gear (5), spider (9), four pinions (10) and side gear (13). Spider (9) is installed between the two parts of the case. When the case is turned, the spider turns.
Pinions (10) are installed on the spider (9). The pinions are engaged with the teeth of side gears (5) and (13). The axle shafts are connected to the side gears by splines.
Side gears (5) and (13) turn against thrust washers (7) and (16). Pinions (10) turn on bearing assemblies (8).
Illustration 2 | g01437147 |
Bevel Gear Group (18) Pinion (19) Nut (20) Bearing (21) Housing (22) Shims (23) Bearing |
Nut (19) is used to adjust the end play (bearing preload) of bearings (20) and (23) for pinion (18).
Shims (22) are used to adjust the tooth contact (wear pattern) between pinion (18) and bevel gear (11).
Adjustment rings (4) and (14) are used to adjust the free movement (backlash) between pinion (18) and bevel gear (11). The adjustment rings are also used to adjust the bearing preload of bearings (3) and (15).
The inside components of the differential receive lubrication from the oil that is thrown around the inside of the differential. Flat surfaces on spider (9) allow oil to flow to the bearings. The supply for lubrication oil is a reservoir in the axle housing.
Straight Forward or Straight Reverse Operation
When the machine moves in a straight direction with the same amount of traction under each drive wheel, the same amount of torque that is on each axle holds the pinions so that the pinions do not turn on the spider.
Pinion (18) turns bevel gear (11). Bevel gear turns case (12). Case turns spider (9). Spider turns side gears (5) and (13) through pinions (10). Pinions do not turn on the spider. The side gears turn the axle shafts. The same amount of torque is sent to each wheel.
Sending the same torque to each wheel provides the same effect as connecting both of the drive wheels to one axle shaft.
Operation during a Forward Turn or Operation during a Reverse Turn
When the machine is turning, the inside wheel is more resistant than the outside wheel to the turn. This resistance causes different torques on the opposite sides of the differential. The outside wheel turns more easily than the inside wheel. The outside wheel starts to turn faster than the inside wheel.
Pinion (18) turns bevel gear (11). Bevel gear turns case (12). Case turns spider (9). Spider turns side gears (5) and (13) through pinions (10). Because one side gear requires more force than the other side gear in order to turn, pinions (10) turn around the spider. As the pinions turn, the pinions move around the side gears allowing the outside wheel to turn faster than the inside wheel.
The same amount of torque is sent to the inside wheels and to the outside wheels. This torque is only equal to the amount that is necessary to turn the outside wheel.
Loss of Traction (Wheel Slippage)
When one wheel has more traction than the other wheel, the differential operates in the same manner as if the machine is turning. The same amount of torque is sent to both wheels. This torque is only equal to the amount that is necessary to turn the wheel with the least resistance.