Patent ID: 6345560
Filing Date: 2002-02-12
Classification: B25B

Abstract:
A clamping chuck with a shank which forms two shank portions (5, 6) and which at one end forms a clamping portion (1) for clamping into a drive member and at the other end forms a toolholder (2) for accommodating a tool, in particular a screwdriver bit (18), an elastic element between the clamping-side shank portion (6) and the toolholder-side shank portion (5) for transmission of torque until a limiting torque (M2) is achieved in a stop-limited manner, up to reaching of said torque the clamping portion (1) and the tool holder (2) rotate relative to one another, the elastic element being inserted in a sleeve comprising the shank portion (6) for torque transmission in event of a torque exceeding the limiting torque (M2), wherein the elastic element is formed by a cylindrical torsion portion in form of a narrowing located between two portions (8, 9, 22) thereof of polygonal shape, the torsion portion forming a torsion member (7) together with the portions (8, 9, 22) of polygonal shape which portions are inserted into correspondingly shaped cavities (10, 11, 23) in the shank portions, the torque transmission between the portions (8, 9, 22) of polygonal shape, which rotate relative to one another through an angular extent (b) until the limiting torque (M2) is reached, and the shaped cavities (10, 11, 23) being effected by positive locking by shape of the portions (8, 9, 22) and the correspondingly shaped cavities (10, 11, 23).