| 摘要 |
PURPOSE:To prevent generation of hunting surely by detecting valve displacement of a counterbalance valve and controlling displacement of a control spool directly by the valve displacement signal. CONSTITUTION:A pressure detector 43 is connected to a passage 11 and the pressure signal detected by the pressure detector 43 is inputed to a control mechanism D whose main elements are an arithmetic unit 40 and a first delay circuit 41, and displacement of a control spool is computed in the control mechanism D and the valve displacement signal is inputed as an exciting current into a comparison solenoid 23. By this, the valve displacement of the control spool is directly controlled by the exciting current, then generation of hunting can surely be prevented. |
