Self-centering element

A self-centering workpiece clamping unit, comprising:

• a first clamping jaw and a second clamping jaw;
• a first centering slide connected to said first clamping jaw and a second centering slide connected to said second clamping jaw;
• a housing;
• pistons guided in a cylindrical hole formed in the housing, each of said pistons having a piston wedge surface;
• a first pair of deflecting pins and a second pair of deflecting pins disposed in said housing, each of said deflecting pins being slidingly guided in a respective one of recesses formed in said housing in a plane located in parallel to a mounting surface of the unit, each of said deflecting pins being provided with wedge bevels at a head end that slide on a respective said piston wedge surface, said cylindrical hole extending in said plane and extending transversely to said recesses with displacement of the pairs of deflecting pins in opposite directions being brought about by the movement of the pistons;
• and
• carrier prisms, each of said carrier prisms being associated respectively to one of said slides and each respectively in contact with a surface of a pair of the deflecting pins and being displaced at right angles to a direction of movement of the deflecting pins and guided in a second plane located in parallel directly above the deflecting pins, the carrier prisms having wedge surfaces which bring about the transmission of forces to the self-centering slides.