| 摘要 |
<p>A hydraulic circuit system capable of making the rise of the driving pressure slow and of preventing the hunting phenomenon even at the start of driving of a hydraulic actuator being high in inertia. The system comprises: a plurality of control valves (15) provided in a discharge piping (10a) of a hydraulic pump (10); and pressure compensating valves (18) respectively provided in pipings for connecting these control valves (15) to respective hydraulic actuators (16); wherein the respective pressure compensating valves (18) are set at the highest load pressure out of respective load pressures of the respective hydraulic actuators (16), and a pump discharge capacity is controlled by a change-over valve (14) actuated by the difference between a pump discharge pressure and a load pressure. A bypass piping (31) connected to a load pressure introducing path (30) for introducing the load pressure into the pressure receiving portion of the aforesaid change-over valve (14) is included, and this bypass piping (31) is connected to a tank through a bypass valve (32) being throttled in the inverse proportion to a change in the opening area of the control valve (15).</p> |
