US Patent 9193045 Tool attachment

A tool attachment for mounting on a hand-held machine tool provided with a tool holder, the tool attachment having an output shaft and a base body at whose outer circumference a locking sleeve is disposed in a manner allowing it to rotate to release at least one assigned locking element; at the outer circumference of the base body, an anti-rotation unit is formed for the twist-proof mounting of the base body on a fastening unit assigned to the hand-held machine tool; on the anti-rotation unit and at an inner circumference of the fastening unit, complementary geometrical forms are provided which are configured to mesh with each other for the releasable, twist-proof mounting of the base body on the fastening unit.