Quick change attachment for clamping chucks

Clamping chuck quick change attachment for a hollow-cylindrical spindle (10), with a locking bush (32) for actuating the chuck clamping which may be shifted in the spindle, an adjusting rod (44) extending through the locking bush (32) which may be connected with the clamping piston rod (70) by means of a coupling arrangement, and with a control bush shiftable between the locking bush (32) and the adjusting rod (44) which may be moved into a closed position by means of a spring (56) supported on the adjusting rod and into an open position via external actuation against the force of the spring for the coupling arrangement, characterized by the fact that the coupling arrangement exhibits several axially fixed coupling pieces (50) in a circumferential groove (48) at the end of the adjusting rod (44) whose free ends carry projections (62) pointing radially inward for engaging the circumferential groove of the clamping piston rod (70) and which are supported by an internal tilting edge (52) on the circumference of the adjusting rod (44) for the execution of plier-like clamping and expanding movements, that the control bush (58) routed in the locking bush (52) overlaps the coupling pieces (5) from outside and exhibits internal annular cams (66, 68), of which one each lies over one or the other end of the coupling pieces in the closed and open positions of the control bush (58) and holds the latter in their closed or expanded state, and that the locking bush (32) is designed as an arrangement for the forcible shifting of the control bush (58) into the closed position.