Aktuator

An actuator for displacing a control device including a valve, a gate valve or the like, in particular for use in oil or gas production systems, said actuator comprising an electric drive and a thread drive displaceable by means of said electric drive. The thread drive comprises at least a threaded spindle and a screw nut. The threaded spindle is displaceable in a substantially axial direction between an advanced position and a retracted position so as to displace the control device. In order to improve an actuator of this kind in such a way that advantages of an already known actuator will be maintained on the basis of a smaller number of components and a more compact structural design and a reduction of the manufacturing costs can simultaneously be accomplished, the electric drive comprises at least one torque motor with a hollow shaft, said hollow shaft being connected to the driven side of a safety clutch unit such that it is secured against rotation relative thereto. This safety clutch unit is, on the driving side thereof, connected in a motion-transmitting manner to the screw nut which is supported such that it is rotatable and axially non-displaceable. In this way, it is additionally achieved that the actuator in question can also be used for units that are already in use.