| 摘要 |
<p>A holding check control valve including a main valve, an assistant valve, a check valve (102) installed in an actuator fluid passage (101) provided at the main valve and provided with a spring chamber (A), the check valve (102) being adapted to be switched between an opened state for opening the actuator fluid passage (101) and a closed state for closing the actuator fluid passage (101) in response to a pressure difference between the actuator fluid passage (101) and the spring chamber (A) so that the return oil in the actuator fluid passage (101) is returned via a return fluid line (105) provided at the main valve at the opened state, a pair of spaced seat members (2a,2b) fixedly disposed in the assistant valve, a hydraulic chamber (4) defined between the seat members (2a,2b), the hydraulic chamber (4) communicating with the spring chamber (A) of the check valve, a plunger (5) extending through the seat members (2a,2b), the plunger (5) being slidable along the seat members (2a,2b) between a position closing the hydraulic chamber (4) and a position opening the hydraulic chamber (4), a pressure setting spring (7) for exerting its resilience on one end of the plunger (5) and thereby always urging the plunger (5) toward the closing position thereof, and a piston (8) for pushing the other end of the plunger (5) and thereby moving the plunger (5) to the opening position thereof against the resilience of the pressure setting spring (7) so that oil in the spring chamber (B) is discharged via the opened hydraulic chamber. <IMAGE> <IMAGE></p> |
