Patent ID: 8870570

Claim:
A medical or dental handpiece comprising: a tool holding/releasing device with a hollow shaft for holding a treatment tool that can be placed in a drive movement, wherein the hollow shaft extends along a central axis and has a tool receptacle opening; a mechanical or fluid driven drive configured to drive the hollow shaft for holding a treatment tool; a first holding unit and a second holding unit separate from the first holding unit, the second holding unit being offset axially from the first holding unit with respect to the central axis, wherein each holding unit is designed to secure a treatment tool supported in the hollow shaft axially and to transmit a torque to the treatment tool, the first holding unit and the second holding unit being configured to hold the treatment tool at different insertion depths, and wherein each holding unit comprises at least one shaped element and a bore penetrating the outer wall of the hollow shaft, in which the at least one shaped element can be held in such a way that it projects through the bore into the interior of the hollow shaft; a locking sleeve operatively coupled to each at least one shaped element that can move relative to the hollow shaft and that surrounds the hollow shaft; and an operating element operatively connected to the locking sleeve for the movement or sliding of the locking sleeve, wherein the locking sleeve is movable at least in an axial direction relative to the hollow shaft to move the holding units into an operating position in which the at least one shaped element of the first holding unit is moved towards the central axis and in which the at least one shaped element of the second holding unit is moved away from the central axis to hold the treatment tool at a selected one of the different insertion depths.