Actuator device

1. An actuator device comprising:

an actuator housing, a driving motor attached to said actuator housing, an actuator spindle, and an auxiliary frame having at least one spring;

said driving motor having a motor spindle being displaceably engaged with said actuator spindle via a nut and said auxiliary frame, such that rotation of said motor produces linear movement of said nut, auxiliary frame and actuator spindle and said nut is releasable from said auxiliary frame to allow linear movement of said auxiliary frame while said nut remains in place relative to said motor spindle, in the event of a power failure;

said auxiliary frame being arranged to displace said actuator spindle independently of said motor; and

said at least one spring being arranged to bias said auxiliary frame while disengaged from said motor spindle.

2. A device in accordance with claim 1 , further comprising said nut being located in a spindle tube associated with said actuator spindle.

3. A device in accordance with claim 2 further comprising a guide;

said guide being rigidly mounted to said auxiliary frame and projecting into said spindle tube; and

said nut abutting said guide such that said guide prevents rotation of said nut relative to said auxiliary frame.

4. A device in accordance with claim 1 further comprising a first coupling and a second coupling;

said nut and said auxiliary frame being releasably interconnected with said actuator spindle and said actuator housing, respectively, by said first and second coupling, respectively.

5. A device in accordance with claim 4 at least one of said first and second couplings comprising a cylindrical body having one or more grooves for engaging a locking body;

said locking body being disposed in a through opening in a retainer ring encircling said cylindrical body; and

said locking body being prevented from displacing out of engagement with said cylindrical body by a locking ring that encircles said retainer ring.

6. A device in accordance with claim 5 , said locking ring comprising one or more recesses which can be brought into a position of correspondence relative to said locking body when said locking ring is rotated about an axial centre line of said locking ring and arranged to move out of engagement with said cylindrical body and into said recess.

7. A device in accordance with claim 6 , further comprising said locking body abutting a corresponding locking arm, when in a locked position;

said locking arm being pivotally supported by said retainer ring;

said locking arm abutting a locking sleeve rotatably supported by an attachment ring via a through locking shaft; and

said locking shaft having a lock bearing abutting said locking ring.

8. A device according to claim 7 wherein a rotation of said locking ring about an axial centre line of said locking ring will displace said locking sleeve out of a locked position.

9. A device in accordance with claim 7 wherein a rotation of said attachment ring about an axial centre line of said attachment ring will displace said locking sleeve out of a locked position.

10. A device in accordance with claim 5 , further comprising said first and second couplings being arranged in parallel.

11. A device in accordance with claim 5 , further comprising said locking bodies having different strengths.

12. A device in accordance with claim 5 , further comprising said groove encircling said cylindrical body.

13. A device in accordance with claim 5 , further comprising said groove running adjacent said cylindrical body.