| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a hydraulic control device for a vehicular automatic transmission capable of disengaging an engagement element by controlling its engagement hydraulic pressure without constraining change-over positions of change-over valves provided between a linear solenoid valve and the engagement element when the engagement element is disengaged. <P>SOLUTION: A check valve 120 is provided between an output port of the linear solenoid valve SL4 and a brake B3 in parallel with a first oil passage change-over valve 108 and a third oil passage change-over valve 118. While allowing a flow of pressure oil from the brake B3 side to the output port side, the check valve 120 shuts off a flow in the reverse direction. Due to this structure, the pressure oil from the brake B3 when it is released is supplied to the output port via the check valve 120 without passing through the first and third oil passage change-over valves 108, 118. Thus, when the brake B3 is released, engagement oil pressure of the brake B3 can be controlled by the linear solenoid valve SL4, and the change-over positions of the first and third oil passage change-over valves 108, 118 cannot be constrained. <P>COPYRIGHT: (C)2010,JPO&INPIT</p> |
