| 摘要 |
PURPOSE:To prevent a resonance of a valve in an oil pressure circuit by a method wherein when an actuator operates in a direction in which load changes occur, a return flow amount from the actuator is squeezed. CONSTITUTION:When the actuator 2 operates in the direction in which load changed are apt to occur, the return flow amount from the actuator 2 to a tank 13 is squeezed by a throttle 14 provided at a changeover valve 6. In this instance, with the inflow amount into the actuator 2 not squeezed in order not to operate a pressure compensating valve 5, the flow amount through the oil pressure circuit 3 is controlled by a counterbalance valve 10 and a relief valve 11, thereby enabling a stable flow amount control even when changes occur in the load. |
