Operating principle of differential (Discovery 3)

The front and rear differentials operate in the same way. The rotational motion of the drive shaft is transmitted through the primary flange to the pinion shaft and the drive pinion. The angular position of the drive pinion relative to the driven pinion ensures that the rotational motion is transmitted at an angle of 90°.

The rotational motion is then transmitted to the driven gear, which in turn sets the differential housing in motion. The shaft, which is attached to the housing, rotates at the same speed as the housing. The planetary gears mounted on the shaft also rotate with the housing. The planetary gears, in turn, transmit the rotational motion to the right and left sun gears, which rotate the axle shafts.

When the vehicle is moving in a straight line, the torques transmitted by the differential to each sun gear are equal. In this condition, both axle shafts rotate at the same speed. The planetary gears do not rotate and securely fix the sun gears to the differential housing.

When a car turns, the outer wheel rotates faster and travels a longer distance than the inner wheel. The differential determines the difference in torque between the sun gears. The planet gears begin to rotate on their axes, allowing the outer wheel to turn faster than the inner wheel.

[Information obtained from the website: www.lrman.ru]