Abstract: A switch, especially for use in a hand-operated storage-battery electric tool with a DC motor is proposed, in which control electronics are provided for changing the speed of the DC motor. In order to produce the switch as compactly as possible and without additional connecting lines to the power transistor and in order furthermore to influence positively the heat budget inside the switch, a contact system (5) and a freewheeling diode (8) are pivoted to a common bearing plate (11) which is connected in current-carrying and heat-conducting fashion via a connecting bolt (12) to a power transistor (7) on the housing. In this arrangement, the power transistor is cooled by a heat sink provided on the switch housing.

Abstract: The invention indicates a device and a process for clamping tools in a clamping chuck which possesses a shrinkage segment (14) to receive the tool, with a heating apparatus (26), preferably designed as a gas burner, being associated with the shrinkage segment (14). The tool is clamped in the clamping chuck (20) with a press fit in the shrinkage seat, resulting in especially high clamping force. To prevent local overheating of the clamping chuck (20) and achieve complete insertion of the tool shaft into the thermally expanded shrinkage segment (14) of the clamping chuck (20), a receiving apparatus (40)--by means of which, for clamping purposes, the tool can be elastically pressed in the axial direction against the shrinkage segment (14)--is provided to receive the tool.