摘要 |
A planetary gear transmission changing forward and reverse drives for vehicles comprises one wet-type brake, one wet-type clutch and a planetary gear set, and is controlled by one shift control valve and one solenoid valve operated by an electric control circuit. Hydraulic pressure supplied to the wet-type brake and the wet-type clutch is regulated in independent oil chambers respectively, resulting in effects of accurate hydraulic pressure regulation and simple structure without wrong operation. |