Oil pressure circuit for clutch

摘要

In addition to a first oil pump directly connected to an engine, a second oil pump is provided which is driven by an electric motor. Accordingly, a start clutch engaging pressure is applied through first and second solenoid-operated valves. The electric motor-driven pump is of the constant pressure type, and therefore its start, at the start of the automobile, can be achieved with a simple control program. After the start of the automobile, the solenoid-operated valve is switched over to the other one, so that the oil pressure is applied from the first oil pump directly connected to the engine, whereby the battery power consumption is minimized. This oil circuit is applied to various kinds of friction engagement clutches.