Patent ID: 8047766

Claim:
An electromechanical drive for actuating a valve of a steam turbine, the electromechanical drive comprising: an electromotor having a rotor with a motor axis; a linear unit including: a screw nut having a power-transmission thread; a piston rod engaged by said power-transmission thread, said piston rod being arranged in at least one section as a spindle, said piston rod having a longitudinal axis, said piston rod being displaceable in a longitudinal direction along said longitudinal axis; a clutch arranged for transmitting a rotational movement of said rotor about said motor axis onto said piston rod; a position pick-up configured to produce an output signal representative of a position of said piston rod in said screw nut; and an electronic control unit configured to control at least one of: at least one of a speed and a rotor position of said rotor about said motor axis dependent upon said output signal and a control signal; and at least one of an engagement of said clutch and a disengagement of said clutch dependent upon said control signal.