Abstract: A tool fastening device comprises a drawbar (21, 22; 47, 48) for clamping a tool holder (10; 40) to a spindle (11; 41) of a machine tool by frictional engagement with a conical bore therein. The drawbar is connected to the tool holder by radially expansible locking means (23; 50) on the drawbar. The locking means is actuated by means of an expansion rod (28; 52). For purposes of facilitating the operation of the expansion rod there is provided forcing means (30; 57) which continuously forces the expansion rod toward the tool holder.

Abstract: The invention deals with a quick-change-device for a conical, hollow bore spindle of a machine tool in particular a milling machine, for the quick releasing and clamping of tools or tool holders that have conical shanks and which have a ring groove on the end which is facing away from the tool, into which radially movable projections of a clamping element engage, and which projections are part of a longitudinally shiftable drawbar in a spindle, which under the effect of clamping springs act on the drawbar, the clamping element engaging and pulling the conical shaft of the tool holder into the spindle cone of the machine tool; and the clamping element is detachable due to compressing the clamping springs through a power means.