Method of forming sleeve for lock rivet

Claim 1

A METHOD FOR FORMING A SLEEVE FOR A LOCK RIVET FROM A CYLINDRICAL BLANK THAT CONSISTS IN (A) FORMING A PRE-HEAD ON ONE END OF SAID BLANK BY UPSETTING SAID END TO A LARGER SIZE THAN THE BLANK WHILE SIMULTANEOUSLY FORMING A FLARED END SOCKET IN SAID PRE-HEAD AND FORESHORTENING SAID BLANK ACCORDINGLY, (B) SUBJECTING THE HEADED BLANK FROM THE HEAD END THEREOF TO LONGITUDINAL EXTRUSION FORCES TO FORM A BLIND CYLINDRICAL PASSAGE IN THE BLANK AND TO SIMULTANEOUSLY FORM A SET OF LONGITUDINAL SLITS IN THE TUBULAR WALL AROUND SAID PASSAGE BY DIVIDING SAID WALL BY EXTRUSION INTO ARCUATE PORTIONS, (C) SIMULTANEOUSLY SUBJECTING THE OPPOSITE END OF THE BLANK TO LONGITUDINAL EXTRUSION IN A DIRECTION TOWARD THE PRE-HEAD THEREOF TO FORM A BLIND CYLINDRICAL DEPRESSION WITH A TUBULAR WALL AROUND SAID DEPRESSION AND TO LEAVE AND INTEGRAL BRIDGE PORTION IN THE BLANK BETWEEN THE BLIND ENDS OF SAID PASSAGE AND DEPRESSION, (D) SEPARATING SAID BRIDGE FROM THE TUBULAR WALL BY SHEARING THE SAME FROM THE BLANK AND DISPLACING IT FROM SAID OPPOSITE END OF THE BLANK ALONG THE AXIS OF THE BLANK WHILE CONTACTING A PORTION OF THE HEAD TO CLOSE THE ENDS OF THE SLITS IN THE HEAD AND FORM A COLLAR EXTENSION ON THE END OF THE HEAD, AND FINALLY, (E) SWAGING THE HEAD TO ITS FINAL SHAPE WHILE REMOVING THE SHEARED BRIDGE FROM THE PASSAGE.

Claim 2

A METHOD FOR FORMING A SLEEVE FOR A LOCK RIVET FROM A CYLINDRICAL BLANK THAT CONSISTS IN (A) FORMING A PRE-HEAD ON ONE END OF SAID BLANK BY UPSETTING SAID END TO A LARGER SIZE THAN THE BLANK WHILE SIMULTANEOUSLY FORMING A FLARED END SOCKET IN SAID PRE-HEAD AND FORESHORTENING SAID BLANK ACCORDINGLY, (B) SUBJECTING THE HEADED BLANK FROM THE HEAD END THEREOF TO LONGITUDINAL EXTRUSION FORCES TO FORM A BLIND CYLINDRICAL PASSAGE IN THE BLANK AND TO SIMULTANEOUSLY FORM A SET OF LONGITUDINAL SLITS IN THE TUBULAR WALL AROUND SAID PASSAGE BY DIVIDING SAID WALL BY EXTRUSION INTO ARCUATE PORTIONS, (C) SIMULTANEOUSLY SUBJECTING THE OPPOSITE END OF THE BLANK TO LONGITUDINAL EXTRUSION IN A DIRECTION TOWARD THE PRE-HEAD THEREOF TO FORM A BLIND CYLINDRICAL DEPRESSION WITH A TUBULAR WALL AROUND SAID DEPRESSION AND TO LEAVE AND INTEGRAL BRIDGE PORTION IN THE BLANK BETWEEN THE BLIND ENDS OF SAID PASSAGE AND DEPRESSION, (D) SEPARATING SAID BRIDGE FROM THE TUBULAR WALL BY SHEARING THE SAME FROM THE BLANK AND DISPLACING IT FROM SAID OPPOSITE END OF THE BLANK ALONG THE AXIS OF THE BLANK WHILE CONTACTING A PORTION OF THE HEAD TO CLOSE THE ENDS OF THE SLITS IN THE HEAD AND FORM A COLLAR EXTENSION ON THE END OF THE HEAD, AND FINALLY, (E) SWAGING THE HEAD TO ITS FINAL SHAPE WHILE REMOVING THE SHEARED BRIDGE FROM THE PASSAGE.