Pem Management, Inc.

Thomas K Litzenberger

James S Franco

A process for cold forging a metal fastener such as a self-clinching standoff includes a punch and die set at the final head trimming station which produces the shear burr only on the underside of the fastener head where it is not visible after installation. A knock-out pin which is reciprocal within the bore of the punch forcibly ejects the fastener through a passage in the die to a point beyond an opposite side of the die. A stripper sleeve which is reciprocal about the outside surface of the punch then moves from a retracted position over the end of the punch pushing a residual scrap ring from around the outside of the punch.

Cold-headed standoff

A method of head trimming a fastener blank in a cold-forging process comprises placing a fastener blank into a bore of a punch having an end face; supporting an underside of a head portion of the fastener blank with the punch end face; moving a die having an internal passage and a trim plate with a cutting edge toward the fastener blank; shearing the head of the fastener blank with the cutting edge of the trim plate; stopping movement of the die at an extended trim position where the cutting edge lies beyond an underside of the head portion of the fastener blank; ejecting the fastener blank from the punch bore and through the die passage to an opposite side of the die; retracting the die; and removing a scrap ring from around the punch by a stripper sleeve.

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Coopersburg, PA, United States of America

Thomas K Litzenberger