Abstract: A hydraulically controllable valve for double-acting consumers that in the lowering mode drains off a flow of load volume from connection B to connection A in throttled fashion. To that end, the valve has a valve seat (5), which communicates with a sealing face (4) of a main piston (3). A pilot piston (8) is guided concentrically in the main piston (3) and communicates with a sealing face (7) to a pilot valve seat (6) in the main piston; the main piston (3) and the pilot piston (8) are held on the valve seat (5) and pilot valve seat (6), respectively, by the load pressure and/or by spring force. On the pressure-relieved side, the pilot piston (8) has a piston shank (9), guided in a seat bore, with a continuously decreasing throttling action and in particular throttle grooves (10), which form a throttle restriction.
Type:
Grant
Filed:
August 28, 1998
Date of Patent:
August 8, 2000
Assignee:
Beringer-Hydraulik AG
Inventors:
Hubert Haussler, Ivan Hristov, Hans Staiger, Josef Zurcher