Patent ID: 8172490

Claim:
Joint between two sub-elements of a tool system which rotates about a rotational axis, in particular for use in machine tools, comprising: an at least partially conical receiver arranged on a first sub-element, the receiver being coaxial with the rotational axis and being delimited by an annular end face; a coupling part arranged on a second sub-element, the coupling part having a coupling pin with a conical surface which is complementary to the conical receiver, the coupling part having an annular plane surface which faces towards the annular end face and, in the coupled state, bears against the latter; a tie bolt projecting axially over the free end of the coupling pin, the tie bolt engaging, in the coupled state, in a cavity adjoining the receiver; and clamping means actuated from the outside for the purpose of mutual clamping of the sub-elements, the clamping means having two clamping elements routed radially in the first sub-element arranged opposite to each other relative to the rotational axis, the two clamping elements carrying, in a clamping position, wedge surfaces which engage beneath a conical portion of the tie bolt that is concentric with the rotational axis, the two clamping elements being operatively connected to common actuating means which are adjustable between a release position and a clamping position, the clamping elements being provided with ejector portions which, in the releasing of the clamping elements from the clamping position, with the exertion of an axial force acting in the ejection direction of the coupling part, strike against an active surface of the tie bolt facing towards the clamping elements, wherein the active surface on the tie bolt side and/or the ejector portions on the clamping element side is/are equipped with at least one rotatably mounted rolling element.