A displacement device for producing a rotational movement with an output element adjustable in angle by operating a drive element. A load torque lock mounted between the drive element and the output element blocks, with force locking connection, torque introduced on the output side and transfers torque introduced on the drive side to the output element. Between the drive element and the load torque lock and/or between the output element and the load torque lock is a play compensating device which compensates the torsion angle play between the drive element, the output element and the load torque lock. The displacement device is used in particular for window lifters or seat adjusters of vehicles.
CROSS-REFERENCE
This application claims priority of German Application No. 199 26 994.7 filed Jun. 8, 1999. This application is also a continuation of patent application Ser. No. 09/592,485, filed Jun. 8, 2000, now abandoned the disclosure of which is incorporated fully herein by reference.
The invention relates to a bidirectional drive for rotating in the one or the other direction of drive a drive wheel which is linked with an adjusting device. The bidirectional drive includes a drive lever which can be rotated about a drive axis, starting from an initial position, in the one or the other direction. The lever is linked with a coupling element for expanding a spring element that is at least partially supported by the cylindrical drive surface of the drive wheel and that entrains the drive wheel in the peripheral direction when the drive lever is moved away from the initial position, while the spring element is no longer supported by the cylindrical drive surface of the drive wheel and the drive wheel is not entrained when the drive lever is returned to the initial position. The coupling element includes expansion cams that can be tilted about an axis spaced apart from the drive axis. The expansion cams expand the actuation lever which is linked with the spring element in such a manner that the spring element which is supported by the cylindrical drive surface of the drive wheel is expanded.
A belt retractor for a vehicle safety belt has a frame, a belt reel which is rotatably mounted in the frame, a locking mechanism which is adapted to block a rotation of the belt reel in an unwinding direction of the safety belt in a vehicle sensitive and/or seat belt sensitive manner and a pretensioning drive which is adapted to drive the belt reel in a wind up direction of the safety belt and in the unwinding direction. A locking means is provided which prevents a reverse rotation of the belt reel in the unwinding direction, after the pretensioning drive has driven the belt reel in the wind up direction and has thereby pretensioned the safety belt.
