Control drive for a control rod in a rotating machine spindle

摘要

The control drive for a control rod (5) axially displaceable in a rotating machine spindle (3) comprises a piston/cylinder drive unit (9) which is arranged coaxially to the spindle axis and is displaceably guided with axial clearance of motion as a unit relative to the machine spindle (3) and to the control rod (5) on a guide (13) fixed to the machine. Via radially movable locking elements (41), the cylinder (11) of the unit (9) is coupled to an annular shoulder (53) of the machine spindle (3) in such a way that it can be subjected to tension. The locking elements are released or locked by thrust faces (57) of the piston rod (23) after overcoming a control-rod working stroke established by a stop element (39). The unit (9) is especially suitable as a release unit for a tool chuck and can be fitted irrespective of the rotary position of the machine spindle (3). For connection to the unit (9), the machine spindle (3) carries no loose parts and thus no parts impairing the balance. <IMAGE>