Patent ID: 7806797

Claim:
An axial setting device in the form of a ball ramp assembly for actuating a friction coupling in the driveline of a motor vehicle, comprising: two discs which are centered on a common axis (A), of which one is axially supported and the other one is axially displaceable and of which at least one is rotatingly drivable; the two discs, on their end faces facing one another, each comprises a plurality of ball grooves extending solely in the circumferential direction; wherein in a plan view of the end faces, the ball grooves, starting from a region of the greatest groove depth, each comprises a depth which decreases in the same circumferential direction, wherein each pair of opposed ball grooves accommodates a ball via which the first and the second discs are supported relative to one another; wherein at least the ball grooves of one of the two discs, starting from the region of the greatest groove depth, comprise a first groove portion with a greater pitch and an adjoining second groove portion with a smaller pitch, the two pitches being different from zero, wherein the first groove portion extends over a smaller circular-arch-shaped portion (α) than the second groove portion which extends over a larger circular-arch-shaped portion (β); and wherein, in the region adjoining a starting position defined by a maximum groove depth, all the ball grooves of the two discs comprise a rising run-out, which has a greater radius than the balls.