| 摘要 |
<p>1,069,286. Fluid-pressure servomotor systems. SOC. ANON. ANDRE CITROEN. Aug. 4, 1964 [July 17, 1963], No.30553/64. Addition to 988, 780. Heading G3P. A device for maintaining pressure in an accumulator A. C. between two predetermined limits, the accumulator being supplied through a non-return valve S and having an outlet 7, comprises two slide valves T1, T2 subjected to accumulator pressure and loaded by springs R1, R2 in chambers E1, E2. The spring R1 is calibrated to balance the lower pressure and the spring R2 the upper pressure. The valve T1 controls the connection of the supply A to a drain passage Z while the valve T2 controls the connection of a passage H from the chamber E1 to drain passage D or a passage L which is in constant communication with the supply A. With the valves T1, T2 in the position shown, the supply is feeding the accumulator. When the accumulator pressure reaches the upper limit, the valve T2 is lowered to connect the chamber E1 to drain whereupon the valve T1 moves downward to connect the supply A to drain. As soon as the accumulator pressure falls, the valve T2 moves upwards but since the supply is connected to drain, the pressure in chamber E1 remains at drain pressure and the valve T1 does not move upwards under the action of spring R1 until the accumulator pressure has fallen to the lower limit, after which the supply then feeds the accumulator.</p> |
