CYLINDER GP 9J1822 - Caterpillar

Differential And Bevel Gear
DIFFERENTIAL
1. Pinion shaft. 2. Pinions (four). 3. Bevel gear. 4. Spider. 5. Side gears (two).The gear on the transmission output shaft is engaged with the transfer output shaft gear which sends power through universal joints to the drive shafts. The drive shafts are connected with splines to the pinion shaft (1). The pinion shaft turns the bevel gear (3) which is fastened to the differential case. The differential case contains four pinions (2), installed on a spider (4), and two side gears (5). The four pinions are engaged at right angles with the two side gears. The side gears are connected with splines to the inner ends of the drive axles.The differential makes the torque equal that goes to both drive wheels. When one wheel is turning slower than the other, as in a turn, the differential permits the inside wheel to stop or slow in relation to the outside wheel.When the machine is moving straight ahead with equal traction under each drive wheel, equal torque on each axle stops the pinions (2) so they will not turn on the spider (4). This gives the same action as if both drive wheels were locked on the same driving axle. When loads that are not equal are put on the drive wheels, as in a turn, forces that are not equal are put on opposite sides of the differential causing the pinions (2) to turn. When the pinions are turning, the inside wheel slows or stops and increases the turning of the outside wheel. This action causes the machine to be driven with full power in a turn.The hubs of the differential cases are installed on the differential carrier with tapered roller bearings. The pinions (2) turn on hardened steel bearings. Both the pinions (2) and side gears (5) turn against thrust washers which take the end thrust against the differential case.The differential gets lubrication from oil thrown about by the moving parts. Flat surfaces on the spider permit passage of oil for lubrication to the pinion bearings and the thrust washers.Differential Lock
When one drive wheel has bad traction, the other wheel turns freely. This action causes a loss of power which is stopped by the differential lock. This is done by sending power to both wheels through a jaw clutch. The jaw clutch lets the differential engage or release while machine is using full power at any speed. The jaw clutch can be engaged at any speed before the wheels start to turn freely. The operator must choose the time he needs to engage the jaw clutch. An example of one such need is, when one wheel starts to turn freely, or a noise is caused by the jaw clutches hitting each other, lower the engine speed to let the jaw clutches engage.The operator must keep the pedal for the differential lock pushed down to keep the jaw clutches engaged. When the differential lock is engaged, the speed of the wheels is the same. The