The drive-shaped tool (1) is secured on a shaft (2) of a separating grinding machine etc. by a chuck (10). This ensures that the tool is clamped between a radial shaft face (5) and a pressure exerting component (11), which can be powered for clamping and release by a rotary rim (25) with a transmission. There are coupling members effective, on rotation of the rotary ring in the clamping direction, to couple the pressure exerting component by positive engagement to the shaft or a component located non-rotatably on the shaft. They are mounted between the pressure exerting component and the shaft.
