| 摘要 |
<p>A hydraulic valve for controlling a hydraulically-operated surgical table and the like comprising a body having a piston slidable in a piston chamber. Normally closed outlet check valves communicate with the chamber on opposite sides of the piston. Similarly located on each side of the piston are respective normally-closed inlet valves and relief valves. Slidable plungers are carried by the piston and may be rotated into and out of alignment with the associated check valve. In operation, the piston is rotated to align a selected plunger with an associated check valve and a fluid under pressure is introduced into the chamber on the opposite side of the piston to force the plunger against the associated check valve to open the same and permit the fluid to flow to and operate the load.</p> |
