Patent ID: 7762560

Claim:
A clamping chuck, having a chuck body ( 1 ) and clamping jaws ( 3 ) that are arranged shiftably in radial jaw guides ( 2 ) of the chuck body ( 1 ), pockets ( 10 ) in which conveying elements ( 9 ) are guided in radially movable fashion being embodied in the chuck body ( 1 ), and means being provided for pumping lubricant that collects in the pockets ( 10 ) into lubricating orifices ( 27 ), and through the latter to desired lubrication points, by way of the radial motion of the conveying elements ( 9 ), wherein there is provided in each pocket ( 10 ) at least one pump piston ( 17 ) that is arranged in a cylinder bore ( 18 ) of the conveying element ( 9 ) that is movable in the pocket ( 10 ), forming a piston space ( 19 ) located therebetween, and is held in the pocket ( 10 ) in such a way that the conveying element ( 9 ), in the context of its radial motions, moves relative to the pump piston ( 17 ) while making the piston space ( 19 ) smaller and larger; the pump piston ( 17 ) protrudes, with a radially outer, tubular end portion ( 17 b ), through the conveying element ( 9 ) and projects into the radially outer region of the pocket ( 10 ), the tubular end portion ( 17 b ) being connected via a connecting conduit ( 22 ) to the piston space ( 19 ); a first nonreturn valve ( 24 ), which permits a fluid flow from the pocket ( 10 ) through the tubular end portion ( 17 b ) and the connecting conduit ( 22 ) into the piston space ( 19 ) but blocks a lubricant flow in the opposite direction, is provided in the pump piston ( 17 ); and the piston space ( 19 ) is connected to a lubricating orifice ( 27 ) of the chuck body ( 1 ) through an outlet conduit ( 26 ) embodied in the conveying element ( 9 ), and a second nonreturn valve ( 29 ) is provided which allows a lubricant flow from the piston chamber ( 19 ) to the lubricant conduit ( 27 ) but prevents a backflow of lubricant in the opposite direction.