| 摘要 |
<p>A hydraulic system has valve units each with valves which may be parallel switched between the pump and the supply and return conduits of the control units, as well as between the latter conduits and the return conduit to the tank. Pressure compensation valves adjust the opening dependant upon the pressure difference above the corresponding direction valve. A second pressure compensation unit has a single valve between the pump supply and return conduit, to form an auxiliary connection to the direction valve. Pre-control pressure monitors between each direction valve, and the second compensation valve, monitor the fluid pressure and the valve position, and contain back pressure valves connected to each direction valve, to transmit the pressurised fluid from the valve under the highest pressure, to the second compensation valve. A pressure-compensated relief valve coupled to the monitors, releases a small amount of fluid from the monitors at any time, when under pressure.</p> |
