Quick-change mount for chucks

A quick-change mount for chucks is incorporated into a rotatable hollow spindle (10) of a machine tool and comprises servo-actuated drive sleeve (32) for power transmission to clamp the chuck (20) to the spindle flange (12). Slidable within the drive sleeve is a servodriven clamping sleeve (46) adapted for having fitted thereto the clamping jaw carrier (70) of the chuck. The clamping sleeve includes an annular series of holes (52) for guiding radially movable coupling element (50), which in order to get into coupling condition are displaced partially into a circumferential groove (72) of the clamping jaw carrier by means of a shifting sleeve (58), and in order to bring about the release condition are enabled to leave said groove for an annular recess (60) of the shifting sleeve (58). The shifting sleeve is spring biased into the condition to bring about the coupling position, from which it can be released by means of a catch member (64), when the fixation of the chuck is removed (FIG. 1).