Vehicle hydraulic transmission with air-released main clutch - has torque converter lock-up clutch engaged at predetermined speed, and main clutch released by solenoid valve controlled air motor

摘要

The vehicle transmission includes an air released main clutch connected between a torque convertor and multiple ratio gear transmission. A lock up clutch for the converter turbine and impeller is engaged by hydraulic pressure when an engine drive governor reaches a predetermined speed and opens a governor valve. The main clutch is released by a motor controlled by a solenoid valve which selectively connects the motor to a source of air pressure or to atmosphere via a restricted orifice and a normally closed air inlet valve. The restriction retarts the engagement of the main clutch when the engine is rotating below the predetermined speed, above which, the governor valve opens to engage the lock-up clutch and to open the air inlet valve so that the main clutch may be engaged at a faster rate.