Actuator having electric drive for actuating a valve device

A device for actuating a valve, comprising:

• an actuator engageable with the valve via an actuating element, the actuator having:
• an electric drive comprising at least one torque motor;
• a hollow shaft within the torque motor and directly driven by the torque motor for movement in a rotational manner;
• and
• a threaded drive which is driven directly by the hollow shaft, the threaded drive comprising a screw nut having an internal thread;
• and a threaded spindle coupled to the actuating element and movably engaged with the screw nut such that rotation of the screw nut via the electric drive causes the threaded spindle to move linearly which, in turn, moves the actuating element linearly, wherein the hollow shaft is supported radially and axially in an actuator housing for rotation with respect to the actuator housing via the torque motor and further wherein the actuator housing may be filled with a fluid for adjusting internal housing pressure relative to external housing pressure, the hollow shaft having a fluid passage therethrough which allows communication of the fluid between an interior and an exterior of the hollow shaft.

A system, comprising:

• an actuator having an actuating element linearly movable between actuating positions, the actuator comprising:
• a torque motor having a stator and a rotor;
• a hollow shaft, the rotor being arranged on the hollow shaft to form a combined internal rotor of the torque motor;
• a screw nut disposed within the hollow shaft and rotatably driven by the hollow shaft, the screw nut having an outer collar engaged with an inner collar of the hollow shaft to counter axial loading on the screw nut, the outer collar further being rotationally locked to the inner collar;
• a threaded spindle coupled to the actuating element and movably engaged with the screw nut such that rotation of the screw nut via the torque motor causes the threaded spindle to move linearly which, in turn, moves the actuating element linearly and
• wherein the hollow shaft having a fluid passage therethrough which allows communication of the fluid between an interior and an exterior of the hollow shaft.