The spindle is mounted in a tool head and secured through at least one preferably ball-shaped locking element (41) which has an associated elastic element (43) formed by a spring (44). The locking element is associated with a locking bush (23) which is displaceable in the longitudinal axial direction of the spindle and is connected rotationally secured with it. Movement of the bush when coupling the spindle to the drive is damped by spring element (62) whose elasticity is less than that of the elastic element (43). The socket for the locking element is provided on a flange (47) connected to the socket shaft (1).
