Drive device for control slide of 4/3-way valve, has rotor movable with control slide in axial direction, and spring moving rotor and control slide to safe identified position and safe identified condition of hydraulic valve

摘要

The device (4) has a processor for controlling individual phases of a brushless direct current motor (7) and for providing information about actual position of a control slide (3) during operation of the device. Force and form-fit connection between a switching device (13) and a threaded spindle (12) is removed during a failure or fault condition. A rotor (10) is movable with the control slide in an axial direction, and a spring (15) moves the rotor and the control slide to a safe identified position and a safe identified condition of a hydraulic valve (1).