Planetary Gears: Description and Operation

Construction
The planetary gear unit is composed of planetary gears, clutches which transmit power to the planetary gears, and brakes and one-way clutches which immobilize the planetary carrier and planetary sungear. Number of unit:







Operation
Power from the engine transmitted to the input shaft via the torque converter is then transmitted to the planetary gears by the operation of the clutch. By operation of the brake and one-way clutch, either the planetary or the planetary sun gear are immobilized, altering the speed of revolution of the planetary gear unit.

Shift change is carried out by altering the combination of clutch and brake operation.

Each clutch and brake operates by hydraulic pressure; gear position is decided according to the throttle opening angle and vehicle speed, and shift change automatically occurs.

The conditions of operation for each gear position are shown in the images.