| 摘要 |
A proportional pressure-regulating valve for an actuator (16) has a main valve (11) having a valve spool (20) which is axially displaceable from a neutral mid-position, blocking a valve port (21) connected to the actuator (16), to either side into a further position in which the valve port (21) is connected to a supply port (22) or an exhaust port (23). When the valve spool (20) is uncontrolled, it is moved by a return spring (33) into a fourth, end position in which the port (21) is isolated from both valve ports (22, 23). The valve spool (20) is rigidly connected to a damping piston (36), which de-limits a damping chamber (35). The damping chamber (35) is connected to a pilot valve (12) providing the valve spool (20) with control pressure medium. Under normal operating conditions, a minimum pressure in the damping chamber (35) prevents the damping piston (36) from entering the chamber and so deters movement of the valve spool (20) to its fourth, end position. <IMAGE> |
