Differential (Standard)
Illustration 1 | g00505876 |
Standard Differential for (S/N: 9WM1-12981WN1-898) (1) Bevel pinion. (2) Side gear. (3) Differential case. (4) Pinion. (5) Shaft. (6) Bevel gear. (7) Sun gear. |
Illustration 2 | g00541284 |
Standard Differential for (S/N: 9WM1299-UP1WN899-UP) (1) Bevel pinion. (2) Side gear. (3) Differential case. (4) Pinion. (5) Shaft. (6) Bevel gear. (7) Sun gear. |
A differential divides the power that is sent to the wheels or a differential causes a balance of the power that is sent to the wheels. A differential allows one wheel to turn at a slower rate than the other wheel on an axle. For example, this occurs during a turn. During a turn, 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.
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 on each axle holds the pinions. This is done so that the pinions do not turn on the spider.
Bevel pinion (1) turns bevel gear (6). Bevel gear (6) turns case (3). Case (3) turns shaft (5). Shaft (5) turns side gears (2) through pinions (4). Pinions (4) do not turn on the shaft. The side gears turn. The side gears turn the left sun gear (7) and the right sun gear (7).
The same amount of torque is sent through the final drives to each wheel. This provides the same effect as having both drive wheels on the same axle shaft.
Operation during a Forward Turn or Operation during a Reverse Turn
When the machine is in a turn, the inside wheel is more resistant than the outside wheel to 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 begins to turn faster than the inside wheel.
The same amount of torque is sent through the final drives to both the inside wheels and to the outside wheels. This torque is only equal to the amount of torque that is necessary to turn the outside wheel.
Loss of Traction (Wheel Slippage)
If one wheel loses traction and the wheel slips, the pinion gears of the wheel that is maintaining traction will begin to rotate slowly around the side gear. The slipping wheel will increase in speed until the maximum wheel speed is obtained, or until the remaining drag is equal to the torque that is required on the opposite side. The maximum amount of torque that is transmitted to the tire that is not slipping is equal to the torque on the tire that is slipping.
The bevel pinion (1) turns the bevel gear (6). The bevel gear (6) is bolted to the differential case (3). The differential case (3) turns the shaft (5). The shaft (5) turns the side gears (2) through the pinions (4). One side gear requires more force than the other side gear in order to turn. This causes pinions (4) to turn around the shaft (5). As the pinions turn, the pinions move around the side gears. This allows the outside wheel to turn faster than the inside wheel.
When one wheel has more traction than the other wheel, the operation of the differential is identical to the operation of the differential during a turn. The same amount of torque is sent to both wheels. This torque is only equal to the amount of torque that is necessary to turn the wheel with the least resistance.
Limited Slip Differential
The limited slip differential is designed to provide equal power to both wheels until the ground conditions cause a variance in traction between the left wheel and the right wheel. The limited slip differential transfers lost power from the wheel with the least traction to the wheel with the most traction.
The limited slip differential is a direct replacement for the standard differential. The limited slip differential is available in both the front axle and the rear axle.
Illustration 3 | g00502055 |
(1) Differential case. (2) Disc pack. (3) Pressure plate. (4) Bevel gear. (5) Side gear. (6) Pinion gear. (7) Shaft. (8) Thrust washer. (9) Side gear. |
The limited slip differential is identical on the left side and the right side of the shaft (7). The limited slip differential contains the following components: bevel gear (4), four pinion gears (6), right side gear (9), two clutch packs (2), two pressure plates (3), differential case (1), shaft (7) and left side gear (5). The right axle shaft is splined to the right side gear (9). The left axle shaft is splined to the left side gear (5).
Illustration 4 | g00504206 |
Components of the Clutch Packs (1) Differential case. (5) Side gear. (6) Pinion gear. (10) Clutch discs. (11) Clutch plates. (12) Pressure disc. |
The clutch pack contains the following components: four clutch discs (10), five clutch plates (11) and pressure disc (12). The clutch discs (10) are splined to the side gears (5) and (9). The clutch plates (11) are splined to the differential case (1).
Illustration 5 | g00502056 |
No Slipping Condition |
The limited slip differential operates identically to a standard differential during straight forward operation or during straight reverse operation. The limited slip differential provides 50 percent torque to each wheel.
When the machine is in a turn, the inside wheel is more resistant than the outside wheel to turn. The resistance in the inside wheel overcomes the clutch pack. The clutch pack slips and the limited slip differential turns the outside wheel identically to a standard differential.
Illustration 6 | g00502058 |
Maximum Slipping Condition |
When one wheel has more traction than the other wheel, the limited slip differential sends the torque to the wheel with the most traction. The clutch packs allow the differential to send the power to the wheel with the most traction. A standard differential could only transfer the same amount of torque from the slipping side to the opposite side.