| 摘要 |
A counterbalance valve assembly for controlling the lowering of an actuator driven load including a housing with a passage connected to deliver fluid to or from one side of the actuator. A main pilot-operated lock check valve is provided in this passage to selectively block flow from the actuator when it is desired that the load be held and also to move to an open position permitting return flow from the actuator with the open valve defining an orifice. The speed of the load is controlled by maintaining a constant pressure drop across this orifice with a compensator valve upstream of the main check valve, which serves the purpose of throttling flow from the actuator to the check valve.
|
