| 摘要 |
The piston pump is for a hydraulic system, partic. in a motor vehicle. It comprises a cylinder bush (8) with piston (1) controlled inlet ports (13) which is movable against a spring (9) towards the cylinder head (10) by pressure in a chamber (12) to increasingly open a connection from the inlet chamber (19) to an idling circuit. The piston has a co-axial secondary piston (6) in a secondary pump chamber (12). This chamber communicates with the chamber (19) via piston (6)-controlled inlet ducts (20, 18) and via a throttle opening (16) in that piston (6). The pistons (1, 6) may be formed as a stepped piston whose smaller-dia. portion is the main piston (1). |
