Patent ID: 7287940

Claim:
A device for fastening a tool to a shaft, having a drawbar with a longitudinal axis, which drawbar is axially displaceable in the shaft and is intended for releasably locking a tool fastened to the shaft, for an automatic tool change in machine tools, characterized in that the drawbar ( 3 ) is accommodated in the shaft ( 2 ) in a rotationally locked manner and has an external thread ( 4 ), a threaded body ( 5 ) having a corresponding internal thread ( 6 ) being provided on the external thread ( 4 ) and also having an external thread ( 25 ) which is accommodated in a corresponding internal thread ( 26 ) of the device ( 1 ), and the drawbar ( 3 ), for the tool change, being axially displaceable by rotating the threaded body ( 5 ) inside the shaft ( 2 ).