Actuating device

1. An actuation device for adjusting a powered control device in the shift direction, the actuation device comprising:

an actuator element axially displaceable in a housing by a feed device at least in the shift direction;

an emergency actuation arrangement actuatable from outside the housing of the device and connectable in motion with the feed device via a direction-switched coupling device to displace the actuator element in the shift direction;

the feed device comprising at least one motor capable of rotating a rotating spindle in an advance rotation direction to axially displace the rotating spindle in at least the shift direction, the rotating spindle connected against relative rotation with a rotating sleeve; and

the rotating sleeve being lockable against rotation in a return rotation direction such that the rotating spindle is prevented from moving axially in a direction opposite the shift direction.

2. The actuation device as in claim 1 , wherein the direction-switched coupling device further comprises a clutch unit that operates unidirectional in the advance rotation direction.

3. The actuation device as in claim 1 , wherein the rotating sleeve is lockable against rotation in the return rotation direction by a volute spring engageable to connect the rotating sleeve with a circular flange connected to the housing.

4. The actuation device as in claim 3 , wherein the volute spring connects to an emergency release unit capable of resetting the actuator element in a direction opposite the shift direction, the emergency release unit comprising a tensioning sleeve for engaging the volute spring, the tensioning sleeve torqueable in the return rotation direction by the powered control device, rotatable between a tensioned and a relaxed position by means of a tensioning motor, and releasably retainable in the tensioned position by the tensioning motor.

5. The actuation device as in claim 4 , wherein the tensioning motor is mounted within the housing.

6. The actuation device as in claim 4 , wherein the emergency release unit further comprises a return spring tensionable to apply torque on the tensioning sleeve and move the tensioning sleeve to the relaxed position upon release by the tensioning motor, the return spring mountable between the tensioning sleeve and the system enclosure or on a component rigidly attached to the housing.

7. The actuation device as in claim 6 , wherein the rigid component is an enclosure lid attachable to an exit end of the housing.

8. The actuation device as in claim 1 , wherein the emergency actuation arrangement comprises a rotatably mounted auxiliary trunnion that protrudes from an interior space in the housing and is operationally linked to a directional clutch unit in the interior space.

9. The actuation device as in claim 8 , wherein the directional clutch unit is mounted on a motor shaft extending from the motor opposite the rotating spindle.

10. The actuation device as in claim 8 , wherein the directional clutch unit is a free-wheeling gear with an associated coaster mechanism, which gear engages in a drive gear positioned on the auxiliary trunnion.

11. The actuation device as in claim 8 , wherein a slip-ring coupling is provided between the auxiliary trunnion and a drive gear.

12. The actuation device as in claim 8 , further comprising:

the rotating sleeve being lockable against rotation in the return rotation direction by a volute spring engageable to connect the rotating sleeve with a circular flange connected to the housing; and

an emergency release unit capable of resetting the actuator element in a direction opposite the shift direction, the emergency release unit comprising a tensioning sleeve engaged with the volute spring, the tensioning sleeve torqueable in the return rotation direction by the powered control device, rotatable between a tensioned and a relaxed position by means of a tensioning motor, and releasably retainable in the tensioned position by the tensioning motor; and

a tensioning-motor shaft that protrudes from the tensioning motor opposite the tensioning sleeve and is operationally linked to the auxiliary trunnion.

13. The actuation device as in claim 12 , wherein the directional clutch unit is a free-wheeling gear with an associated coaster mechanism, which gear engages in a drive gear positioned on the auxiliary trunnion and wherein the tensioning-motor shaft is operationally connected to the drive gear or to the free-wheeling gear.

14. The actuation device as in claim 12 , further comprising:

wherein the directional clutch unit is a free-wheeling gear with an associated coaster mechanism, the gear engaging a drive gear positioned on the auxiliary trunnion;

a sleeve nut connecting a free end of the tensioning-motor shaft to a threaded spindle; and

a tensioning gear engaging the threaded spindle and operationally connecting the tensioning-motor shaft and the drive gear or free-wheeling gear.

15. The actuation device as in claim 14 , wherein a slip-ring coupling is associated with the tensioning gear.

16. The actuation device as in claim 14 wherein the sleeve nut is movable in substantially non-rotational fashion between two stops along the tensioning-motor shaft and, respectively, the threaded spindle.

17. The actuation device as in claim 14 , wherein the threaded spindle is rotatably mounted at its spindle end opposite the tensioning-motor shaft.

18. The actuation device as in claim 17 , wherein the spindle end and/or the auxiliary trunnion are rotatably mounted in a motor cover removably attachable to the housing.

19. The actuation device as in claim 18 , wherein the spindle end and/or the auxiliary trunnion are rotatably mounted in the motor cover using at least one removably attached bearing box.

20. The actuation device as in claim 12 , wherein at least one positional sensor is associated with the threaded spindle and/or the tensioning-motor shaft and/or the motor shaft.