Steuerventileinrichtung für Drucköl.

摘要

A control valve assembly (1) for a pressurized oil has a valve chamber (4) within which a pressure supply valve seat (15), a first chamber (11), a short-circuit prevention valve seat (17), a second chamber (12) and a return valve seat (16) are arranged in order. A check valve member (19) inserted into the first chamber (11) is adapted to be resiliently urged to the pressure supply valve seat (15) for valve closing by means of a valve closing spring (20) through a resilient sealing member (21). A return valve member (22) and a short-circuit prevention valve member (23) are inserted in to the second chamber (12) in series. The return valve member (22) is adapted to be resiliently urged to the return valve seat (16) for valve closing by means of another valve closing spring (30). Under a pressure released condition in which the return operation means is operated, the short-circuit prevention valve member (23) is adapted to be actuated toward the short-circuit prevention valve seat (17) for valve closing by a valve opening member (43) through the return valve member (22).