| 摘要 |
PROBLEM TO BE SOLVED: To avoid the generation of an engagement shock at a friction engagement element even if the discharge pressure of a pump is abruptly increased at the automatic start of a prime mover.SOLUTION: A D-pressure oil passage L4 connected to an input port 48a of a linear solenoid valve SL1 is made to communicate with a secondary pressure oil passage L2 via a drain oil passage L10 in which an orifice 71 is formed. By this, an abrupt increase of the drive pressure (line pressure PL) of the D-pressure oil passage L4 can be suppressed even if the discharge pressure of a mechanical oil pump 42 operated by the power of an engine is temporarily abruptly increased at the automatic start of the engine. As a result, since the abrupt increase of the input pressure of the linear solenoid valve SL1 is suppressed, the generation of an engagement shock of a clutch C1 resulting from the abrupt increase of the input pressure can be suppressed. |
