Patent ID: 8840653

Claim:
A two-piece clamping element comprising two separate opposing first and second clamping jaws each having a recessed surface extending along a first axis forming a laterally open expandable cavity extending between first and second outer side surfaces of each clamping jaw to receive a rod-shaped element, with each clamping jaw having a bore aligned with one another, wherein a pivot bearing is arranged opposite said cavity allowing the two opposing clamping jaws to come into contact with one another, wherein the pivot bearing comprises at least one set of complementary pivot bearing surfaces portions, wherein the set of complementary pivot bearing surfaces portions are pivotally engaged and comprise a protrusion with a part-cylindrical surface in the first clamping jaw and a complementary groove with a part-cylindrical surface in the second clamping jaw, the part-cylindrical surface in the first clamping jaw being concave and the part-cylindrical surface in the second clamping jaw being convex, the convex and concave part-cylindrical surfaces are in contact and pivot against one another as the laterally open cavity expands, the first and second clamping jaws further comprising an anti-rotation protrusion on one of the clamping jaws and an anti-rotation recess located in the other of the jaws for receiving the anti-rotation protrusion, the anti-rotation protrusion and recess being located on an open outer surface of the first and second clamping jaws, the part-cylindrical surfaces of the protrusion and complementary groove of the pivot bearing extend between the first and second outer side surfaces of the clamping jaws and the anti-rotation protrusion along an axis perpendicular to the first axis, and wherein the anti-rotation protrusion has a rectangular shape having four side surfaces.