| 摘要 |
<p>772,672. Valves controlled by pilot valves. SCHMIDT, F. July 13, 1954 [Oct. 29, 1953; April 30, 1954], No. 20500/54. Class 135. An hydraulic device for controlling a machine tool includes a loose ball valve 3 which shuttles between a pair of rubber ring seats 4 and controls the interconnection of a pressure inlet 2, an exhaust 9, and a port 6 leading to the working cylinder. In the upper position of the valve, the working cylinder is vented, and in the lower position, pressure liquid is supplied to the cylinder. The seats 4 are separated by a cage 5. The valve is actuated by a loose piston 8 under the control of a valve 13, the latter connecting the lower face of the piston either to the pressure liquid inlet 2 or to an exhaust port 16. Valve 13 is actuated in both directions by a double electromagnet 18<SP>1</SP>. The exhaust and pressure liquid supply passages run transversely through the valve casing so that a number of such casings can be assembled into a unit.</p> |
