Abstract: A shrinking arrangement for a tool holder is provided which retains a rotary tool with a press fit in a central accommodation opening. The arrangement includes an induction-heating arrangement for thermally expanding the tool holder in the region of the accommodating opening. The induction-heating arrangement includes an induction-coil unit which is guided on a vertical guide column such that it can be displaced with its coil axis vertical and which is connected, in particular via a flexible cable, to an induction-current generator which is fixed in relation to the column, and in that arranged on the induction-coil unit is a contact switch which can be actuated manually and by means of which the supply of induction current to the induction-coil unit can be switched on and off in a freely selectable manner at least for a limited period of time.

Abstract: A presetting device is proposed for a tool holder (1) which holds the shank (23) of a rotary tool (3) in an interference fit in a locating opening (5) and releases said shank (23) during heating, in particular by means of an induction heating arrangement (7), and which has inside the locating opening (5) an axially adjustable positioning stop surface (21) for the tool shank (23). The presetting device comprises a holder receptacle (11), which holds the tool holder (1) in an axial position and has an opposing reference surface (25), and means (43) for measuring the axial overall length of the rotary tool (3). The presetting device also comprises a measuring device (27) which measures the axial distance between the positioning stop surface (21) of the tool holder (1) and the opposing reference surface (25) of the holder receptacle (11) and has a measured-value indicator (55), the indicated distance value of which can be increased by the measured value of the overall length of the rotary tool (3).