Patent ID: 7051860

Claim:
A displacement device for producing a rotary movement, comprising: a drive element; an output element which can be adjusted in angle by the drive element; a load torque lock which is mounted between the drive element and the output element and which blocks torque introduced from the output element on an output side through force-locking engagement and transfers torque introduced from the drive element on a drive side to the output element, wherein the load torque lock includes rigid locking elements; a play compensating device which compensates a torsion angle play between the drive element, the output element and the load torque lock, wherein the play compensating device is located at least one of between the drive element and the load torque lock and between the output element and the load torque lock; and at least two locking elements with expanding faces; wherein the drive element has a wedge slide guide; wherein the play compensating device has at least one wedge with wedge faces and a wedge guide, the wedge mounted between the expanding faces of the at least two locking elements with the wedge faces set opposite the expanding faces of the locking elements and guided displaceable with the wedge guide in positive locking engagement in the wedge slide guide of the drive element and pretensioned radially by means of a spring so that the wedge faces adjoin the expanding faces free of play; wherein a matching of materials of the expanding faces and the wedge faces on one side and active faces of the wedge guide and wedge slide guide of the drive element on the other side is such that in the absence of any drive torque the expanding faces can move the wedge against the action of the spring and that in the event of strain on the drive side the wedge is held in position; and wherein α is the wedge angle which the wedge faces include between themselves, σ sperr,min is the minimum friction angle, σ sperr,max is the maximum friction angle between the wedge faces and the expanding faces, σ antr,min is the minimum friction angle between the wedge guide and the wedge slide guide and the following conditions are met 2*σ sperr,max <α σ antr,min +σ sperr,min >α/2 in which σ=arc tan μ and μ is the friction value between the friction faces formed from expanding faces and the wedge faces in the case of σ sperr,max and σ sperr,min and the active faces of the wedge guide and wedge slide guide in the case of σ antr,min .