摘要 |
Pressure compensated hydraulic systems are useful in reducing the expenditure of energy when the system is in operation but not being used. Optimizing the operating characteristics for certain applications increases the response time due to no load pressure or cavitation in the hydraulic jack being actuated. The pressure compensated hydraulic system includes a restriction disposed in a pilot passage which normally subjects pump discharge pressure to one end of an unloading valve. A control passage is connected to the pilot passage between the restriction and the end of the unloading valve and in one mode of operation communicates pressurized fluid through the system and eventually back to the spring end of the unloading valve to move it to a fluid blocking position. In another mode of operation, the control passagae lowers the fluid pressure at the end of the unloading valve allowing a spring to move the unloading valve to the blocking position in the above-mentioned modes of operation, the system response time is greatly improved.
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