Patent ID: 6874790

Claim:
A device for rotation of disc-shaped elements of different diameter, which device comprises a chuck which is rotatable by means of a motor-driven spindle and in which three arms distributed evenly in the peripheral direction are pivotably mounted, the arms having a radially outer stop element for contact with an outer peripheral edge of a disc element inserted in the chuck, and the chuck having a base plate which is connected in a rotationally fixed manner to the spindle and in which each arm is mounted rotatably via a respective pin which, via a gearwheel mounted thereon, is in engagement with a central gearwheel which is mounted rotatably in the base plate and is preloaded by means of tension spring elements towards a rotational position in which the central gearwheel tends to hold the arms and their stop elements in a pivoted-in position in the chuck, the arms being synchronously pivotable towards a pivoted-out position counter to the action of the tension spring elements in order to receive and, while centering, clamp a disc element in the chuck in order for it to be possible to subject the disc element to rapid rotation therein, wherein the device further comprises a retaining mechanism which is configured to lock the rotation of the central gearwheel relative to the base plate when a predetermined speed of the chuck is reached.