Patent ID: 8585031

Claim:
A quick-action clamping cylinder comprising a housing and a cover covering the housing, the cover having a center opening for receiving a retractable nipple arranged on the lower side of a workpiece pallet, and a plurality of locking elements providing a spring-loaded lock for the retractable nipple in the housing, wherein the locking elements are in locked position in spring-loaded contact with the outer periphery of the retractable nipple and move into unlocked position by disengaging from the retractable nipple through movement of a piston operated by pressure means, wherein the piston has at least one first chamfer with a slope in the radial inward direction, wherein the locking elements contact the first chamfer in the locked position in a first element position for transmitting a load, wherein the locking elements further contact the bottom side of the cover in a second element position, and wherein the locking elements further contact a second chamfer having a slope opposite to the slope of the first chamfer on the outer periphery of the retractable nipple in a third element position.