Abstract: A cutting tool assembly comprising a tool holder with a clamping collet and an interchangeable tool insert with a clamping shaft engageable by the clamping collet, matching conical surfaces on the periphery of the tool holder and of the tool insert providing centering as well as axial and radial force transmitting functions, while cooperating spline profiles on the assembly components provide a separate tangential force transmitting function. The clamping collet and the clamping shaft engage each other with multiple conical coupling faces which, under a pulling action of a rod connected to the collet, produce an axial pull on the tool insert while spreading radially between the clamping shaft and the tool holder to produce a radial wedging action. These conical coupling faces may be part of axially spaced identical ridges, the clamping collet expanding radially to clear the ridges for insertion, or they may be flanks of cooperating threads, the clamping collet being rotatable.

Abstract: A collet, comprising a clamping head having a front side, having interior gripping surfaces in a longitudinal zone of the clamping head for gripping a workpiece, and having an exterior surface in the form of a frustum located at least partially in the same longitudinal zone as the gripping surfaces and diverging toward the front side of the clamping head, the clamping head being divided into individual gripping jaws, at least in the longitudinal zone of the gripping surfaces, by radially- and axially-extending longitudinal slits circumferentially distributed about the clamping head. The collet includes a clamping tube separately couplable with the clamping head and having means on an end of the clamping tube facing away from the clamping head for fastening the clamping tube to an apparatus for use. Elastic members are provided in the longitudinal slits between the gripping jaws of the clamping head.