Fastening and coupling apparatus for a rotating tool, and power tool having a fastening and coupling apparatus of this type

A fastening and coupling apparatus for a rotating tool, which is provided for connection to a drive unit of a power tool having a rotating drive, the fastening and coupling apparatus comprising:

• a coupling shaft with a longitudinal axis, the coupling shaft being rotatable around the longitudinal axis with the aid of the rotating drive when the fastening and coupling apparatus is connected to the drive unit of the power tool;
• a collet for detachably receiving an cylindrical tool shank, which is movable between a clamping position, in which the tool shank is clamped in the collet such that it is rotatably fixedly connected to the coupling shaft and is rotatable around the longitudinal axis, and a releasing position, in which the tool shank is removeable from the collet or inserted into the collet due to a relative movement along the longitudinal axis in relation to a collet receptacle rotatably fixedly connected to the coupling shaft as a single piece;
• a clamping device that includes the collet and the collet receptacle and is configured to maintain the clamping position of the collet in a state unloaded from the outside, to move the collet from the clamping position into the releasing position upon an application of a releasing force to the clamping device from the outside, and to move the collet from the releasing position into the clamping position upon the elimination of the releasing force;
• a releasing device, in relation to which the coupling shaft is rotatable and which is configured to apply the releasing force to the clamping device upon an actuation of the releasing device when the coupling shaft is at a standstill;
• an actuating device adapted to be actuated by the user of the power tool by manual power, and is configured to actuate the releasing device and to end the actuation of the releasing device,
• wherein the actuating device is configured to convert a rotational movement of an actuating element, coaxial to the longitudinal axis and carried out by the user, into a movement along the longitudinal axis for actuating the releasing device,
• wherein the conversion of the rotational movement into the movement along the longitudinal axis takes place via a wedge gear, and
• wherein the wedge gear has two faces arranged opposite each other in the longitudinal direction, at least one of which has at least one section running at an angle in relation to a plane situated perpendicularly to the longitudinal axis, exactly one of the two faces being arranged such that it is rotatable around the longitudinal axis, and exactly one of the two faces being arranged such that it is displaceable along the longitudinal axis, and
• wherein at least one rolling element or at least one ball is arranged between the two faces.