Guided keeper and method for metal forming dies

A guided keeper assembly for metal forming dies of the type having first and second die members mounted a spaced apart distance for reciprocation between converged and diverged positions, comprising:

• a base having a mounting face shaped to abut an adjacent face of the first die member, and a central aperture extending axially through a central portion of said base;
• a guide pin having a cylindrically-shaped central portion closely received in said central aperture of said base for precisely guiding reciprocal motion between the first and second die members, a first end having an enlarged head shaped to abut said base to positively limit travel between the first and second die members, and a second end positioned opposite said first end and having a shoulder with at least a portion thereof shaped for close reception in a guide pin bore in a first face of the second die member to precisely locate said second end of said guide pin in the second die member, and including a threaded end aperture extending axially into said shoulder;
• a first fastener securely, yet detachably, connecting said base with the first die member;
• and
• a locking collar securely, yet detachably, connecting said second end of said guide pin with the second die member, and including;
• a disc-shaped collar body with opposed, circularly shaped inner and outer faces, an axially extending central axis, and a cylindrical outside surface shaped for close reception in a cylindrical collar bore disposed in a second face of the second die member generally opposite the guide pin bore;
• a circular recess disposed in said outer face of said collar body in a concentric relationship therewith, and defining an axially oriented inner side wall;
• an internal retainer ring groove disposed in said side wall of said collar body, and shaped to receive and detachably retain therein an associated retainer ring;
• at least one fastener clearance hole extending axially through said collar body and at least a portion of said circular recess at a location spaced radially off set from said central axis of said collar body and oriented parallel therewith;
• said fastener clearance hole having a counterbored shape with a shank portion disposed adjacent said inner face of said collar body, an enlarged head portion disposed adjacent said outer face of said collar body, and an annular shoulder portion disposed between said shank portion and said head portion;
• a socket head cap screw having a threaded shank portion extending through said shank portion of said fastener clearance hole in said collar body and detachably received and securely retained in said threaded end aperture in said guide pin, and a cylindrically shaped head portion with an exterior end face, an interior end face abutting against and securely seated on said shoulder portion of said fastener clearance hole, and an outside peripheral surface received in said head portion of said fastener clearance hole in said collar body;
• and
• a retainer ring detachably received and securely retained in said retainer ring groove in said collar body, and having an interior face disposed over at least a portion of said exterior end face of said head portion of said cap screw, whereby engagement between said exterior end face of said head portion of said cap screw and said interior face of said retaining ring positively prevents said cap screw from unintentionally unfastening from said end aperture in said guide pin.

A locking collar assembly for metal forming dies of the type having a plurality of guide pins interconnecting first and second die members for reciprocation between converged and diverged positions, comprising:

• a locking collar having:
• a disc-shaped collar body with opposed, circularly shaped inner and outer faces, an axially extending central axis, and a cylindrical outside surface shaped for close reception in a cylindrical collar bore disposed in a first face of the first die member;
• a circular recess disposed in said outer face of said collar body in a concentric relationship therewith, and defining an axially oriented inner side wall;
• an internal retainer ring groove disposed in said side wall of said collar body, and shaped to receive and detachably retain therein an associated retainer ring;
• at least one fastener clearance hole extending axially through said collar body and at least a portion of said circular recess at a location spaced radially off set from said central axis of said collar body and oriented parallel therewith;
• said fastener clearance hole having a counterbored shape with a shank portion disposed adjacent said inner face of said collar body, an enlarged head portion disposed adjacent said outer face of said collar body, and an annular shoulder portion disposed between said shank portion and said head portion;
• a socket head cap screw having a threaded shank portion extending through said shank portion of said fastener clearance hole in said collar body and detachably received and securely retained in a threaded end aperture in an associated one of the guide pins positioned on a second face of the first die member generally opposite the collar bore, and a cylindrically shaped head portion with an exterior end face, an interior end face abutting against and securely seated on said shoulder portion of said fastener clearance hole, and an outside peripheral surface received in said head portion of said fastener clearance hole in said collar body;
• and
• a retainer ring detachably received and securely retained in said retainer ring groove in said collar body, and having an interior face disposed over at least a portion of said exterior end face of said head portion of said cap screw, whereby engagement between said exterior end face of said head portion of said cap screw and said interior face of said retaining ring positively prevents said cap screw from unintentionally unfastening from said end aperture in said one guide pin.

In a method for making a metal forming die of the type having a plurality of guide pins interconnecting first and second die members for reciprocation between converged and diverged positions, the improvement, comprising:

• forming a cylindrically shaped blind collar bore in a first face of the first die member;
• providing a circularly shaped support surface on a second face of the first die shoe at a location generally opposite and aligned with the collar bore, configured to support one end of one of the guide pins thereon;
• forming a disc-shaped collar body with opposed, circularly shaped inner and outer faces, an axially extending central axis, and a cylindrical outside surface shaped for close reception in the collar bore in the first face of the first die member;
• forming a circular recess in the outer face of the collar body in a concentric relationship therewith to form an axially oriented inner side wall in the collar body;
• forming an internal retainer ring groove in the side wall of the collar body shaped to receive and detachably retain therein an associated retainer ring;
• forming at least one fastener clearance hole axially through the collar body and at least a portion of the circular recess at a location spaced radially off set from the central axis of the collar body and oriented parallel therewith;
• the fastener clearance hole having a counterbored shape with a shank portion disposed adjacent the inner face of the collar body, an enlarged head portion disposed adjacent the outer face of the collar body, and an annular shoulder portion disposed between the shank portion and the head portion;
• providing a socket head cap screw with a threaded shank portion and a cylindrically shaped head portion with an exterior end face, an interior end face, and an outside peripheral surface shaped for reception in the head portion of the fastener clearance hole in the collar body;
• inserting the socket head cap screw into the fastener clearance hole in the collar body with the threaded shank portion extending through the shank portion of the fastener clearance hole in the collar body and being detachably received and securely retained in a threaded end aperture in the one guide pin by fully tightening the socket head screw, and with the interior end face of the head portion abutting against and securely seating on the shoulder portion of the fastener clearance hole, and the outside peripheral surface being received in the head portion of the fastener clearance hole in said collar body;
• providing a retainer ring shaped for reception in the retainer ring groove in the collar body, and having an interior face;
• and
• inserting the retainer ring in the retainer ring groove of the collar body with at least a portion of the retainer ring positioned over the exterior end face of the head portion of the cap screw, whereby engagement between the exterior end face of the head portion of the cap screw and the interior face of the retaining ring positively prevents the cap screw from unintentionally unfastening from the end aperture in the one guide pin.