Abstract: A self-attaching nut for attachment to a panel including a central pilot portion having a generally cylindrical outer surface, a flange portion surrounding the outer surface of the pilot portion including an annular groove surrounding the pilot portion having a substantially V-shaped bottom wall and a generally planar panel support surface surrounding the annular groove. The panel support surface includes a plurality of circumferentially spaced radial ribs extending into the annular groove, but spaced from the outer surface of the pilot portion. The grooves may be convex or concave or a combination of convex and concave grooves. In one embodiment, the nuts are rectangular and the back face include two pair of transverse linear grooves for interconnection by frangible wires in side to side relation.

Abstract: A self-attaching nut having a central pilot portion projecting from an end face of the body portion, an annular groove in the end face generally surrounding the pilot portion. The annular groove includes an inner side wall adjacent the pilot portion, a bottom wall and an outer side wall, wherein the bottom wall includes a first plurality of circumferentially spaced anti-rotation elements adjacent the inner side wall each having a planar inclined top face and a second plurality of circumferentially spaced anti-rotation elements adjacent the outer side wall each having a planar inclined top face and wherein the outer side wall of the annular groove includes a plurality of circumferentially spaced notches.

Abstract: A nut feed system and method of feeding nuts through a nut feed passage which avoids contact between the feed pawl and the nut bore. The end face of the nut includes a nut feed groove extending perpendicular to the nut bore and the free end of the feed pawl is received in the groove to drive the nuts through a nut feed passage without contacting the bore. The disclosed embodiment of the nut includes a counterbore through the end face and radial channel-shaped feed grooves and the feed pawl includes a cylindrical center portion and radial portions received in the counterbore and feed grooves.

Abstract: A self-attaching nut having a central pilot projecting from an end face of the body portion, an annular groove surrounding the pilot and an annular panel support face surrounding the groove, wherein the outer side wall includes a plurality of circumferentially spaced notches, each having an outer wall which extends from the bottom wall of the annular groove to the panel support face and the bottom wall of the groove includes a plurality of circumferentially spaced radial ribs integral with either the outer or inner side walls of the annular groove having a radial end spaced from the opposed side wall and a top face inclined toward the bottom wall of the annular groove providing improved torque resistance and push-off strength. Alternating circumferentially overlapping radial ribs integral with the pilot and the outer groove wall and ribs which extend below the bottom wall of the groove are also disclosed.

Abstract: A self-attaching nut having a central pilot projecting from an end face of the body portion, an annular groove surrounding the pilot and an annular panel support face surrounding the groove, wherein the outer side wall includes a plurality of circumferentially spaced notches, each having an outer wall which extends from the bottom wall of the annular groove to the panel support face and the bottom wall of the groove includes a plurality of circumferentially spaced radial ribs integral with either the outer or inner side walls of the annular groove having a radial end spaced from the opposed side wall and a top face inclined toward the bottom wall of the annular groove providing improved torque resistance and push-off strength. Alternating circumferentially overlapping radial ribs integral with the pilot and the outer groove wall and ribs which extend below the bottom wall of the groove are also disclosed.

Abstract: A self-attaching nut having a central pilot projecting from an end face of the body portion, an annular groove surrounding the pilot and an annular panel support face surrounding the groove, wherein the outer side wall includes a plurality of circumferentially spaced notches, each having an outer wall which extends from the bottom wall of the annular groove to the panel support face and the bottom wall of the groove includes a plurality of circumferentially spaced radial ribs integral with either the outer or inner side walls of the annular groove having a radial end spaced from the opposed side wall and a top face inclined toward the bottom wall of the annular groove providing improved torque resistance and push-off strength. Alternating circumferentially overlapping radial ribs integral with the pilot and the outer groove wall and ribs which extend below the bottom wall of the groove are also disclosed.

Abstract: A self-attaching nut having a central pilot projecting from an end face of the body portion, an annular groove surrounding the pilot and an annular panel support face surrounding the groove, wherein the outer side wall includes a plurality of circumferentially spaced notches, each having an outer wall which extends from the bottom wall of the annular groove to the panel support face and the bottom wall of the groove includes a plurality of circumferentially spaced radial ribs integral with either the outer or inner side walls of the annular groove having a radial end spaced from the opposed side wall and a top face inclined toward the bottom wall of the annular groove providing improved torque resistance and push-off strength. Alternating circumferentially overlapping radial ribs integral with the pilot and the outer groove wall and ribs which extend below the bottom wall of the groove are also disclosed.

Abstract: A method of forming pierce and clinch nuts by rolling a section having the desired cross-section, punching equally spaced bores through the central pilot portion and then punching configured openings through the central pilot portion having convex arcuate surfaces and eliminating sharp corners. The strip of interconnected self-attaching fasteners may be installed directly from the strip in a panel, fed in bulk or separate fasteners interconnected by frangible connectors. The resultant self-attaching nut includes a central pilot portion having a bore through the top face, integral flange portions extending from opposed sides and the pilot portion includes convex arcuate faces reducing or eliminating stress cracking and propagation of stress cracks.

Abstract: An assembly line for continuously manufacturing fasteners from a rod with a groove for receiving a wire for retaining the fasteners in a strip includes a receiver for receiving the rod. A die press is arranged to receive the rod from the receiver and includes a piercing member for piercing an aperture in each fastener and a cutting member for cutting each fastener from the rod. A tapping member provides ribs to an inner wall of the aperture formed in the fastener by the piercing member. An inspector inspects the internal rib formed into the inner wall of the aperture disposed in the fastener verifying exactness of the aperture and the rib. A wire inserter inserts the wire into the groove forming a strip of connected fasteners. The inserter receives the fasteners sequentially from the inspector after verification of the exactness of the aperture disposed in each fastener.

Abstract: A method of forming a female fastener including rolling a body portion strip having a midportion and flange portions on opposed sides of the midportion, piercing spaced openings through the midportion, cutting the strip to length between the openings, cold forming a separate generally cylindrical pilot portion having a length greater than the width of the midportion and a diameter greater than the opening through the midportion, preferably including radial splines, and press fitting the pilot portion through the opening in the midportion. The self-attaching female fastener thus includes a rectangular body portion and a generally cylindrical pilot portion having an end face spaced above a plane of the midportion and may be formed of a harder metal than the body portion.

Abstract: A self-attaching nut including a central pilot portion, a flange portion surrounding the pilot portion having an end face including an annular groove in the end face having inclined inner and outer side walls and a plurality of circumferentially spaced radial ribs integral with the outer side wall extending beyond a midportion of the bottom wall, but spaced from the inner side wall. In one embodiment, the top faces of the radial ribs is inclined to adjacent the inner side wall of the annular groove and in another embodiment, the radial inner ends of the ribs are spaced above the plane of the bottom wall and include an inwardly inclined face.

Abstract: A method of forming a female fastener including rolling a body portion strip having a midportion and flange portions on opposed sides of the midportion, piercing spaced openings through the midportion, cutting the strip to length between the openings, cold forming a separate generally cylindrical pilot portion having a length greater than the width of the midportion and a diameter greater than the opening through the midportion, preferably including radial splines, and press fitting the pilot portion through the opening in the midportion. The self-attaching female fastener thus includes a rectangular body portion and a generally cylindrical pilot portion having an end face spaced above a plane of the midportion and may be formed of a harder metal than the body portion.

Abstract: A self-attaching fastener for thick panels having a pilot and a groove in a flange portion including an inclined outer wall and a bottom wall having an inclined portion extending to the outer face of the pilot and a concave surface in the outer face of the pilot adjacent the bottom wall. A die set for various panel thicknesses each having a projecting lip including an end face and first and second inclined faces which deform the panel against the inclined bottom wall and beneath the concave surface of the pilot. And, a method of attaching the fastener to a metal panel, wherein the die lip deforms a panel against the inclined bottom wall portion adjacent the pilot portion, inwardly into the concave surface and outwardly beneath the groove outer wall.

Abstract: A self-attaching nut having a central pilot projecting from an end face of the body portion, an annular groove surrounding the pilot and an annular panel support face surrounding the groove, wherein the outer side wall includes a plurality of circumferentially spaced notches, each having an outer wall which extends from the bottom wall of the annular groove to the panel support face and the bottom wall of the groove includes a plurality of circumferentially spaced radial ribs integral with either the outer or inner side walls of the annular groove having a radial end spaced from the opposed side wall and a top face inclined toward the bottom wall of the annular groove providing improved torque resistance and push-off strength. Alternating circumferentially overlapping radial ribs integral with the pilot and the outer groove wall and ribs which extend below the bottom wall of the groove are also disclosed.

Abstract: A nut feed system and method of feeding nuts through a nut feed passage which avoids contact between the feed pawl and the nut bore. The end face of the nut includes a nut feed groove extending perpendicular to the nut bore and the free end of the feed pawl is received in the groove to drive the nuts through a nut feed passage without contacting the bore. The disclosed embodiment of the nut includes a counterbore through the end face and radial channel-shaped feed grooves and the feed pawl includes a cylindrical center portion and radial portions received in the counterbore and feed grooves.

Abstract: The self-attaching female fastener of this invention includes a re-entrant groove having a V-shaped bottom wall including relatively inclined bottom faces of equal width having an arcuate apex centered beneath the restricted opening to the groove. A die drives a panel portion through the restricted groove opening against the bottom faces, driving the panel portion into the apex and inwardly beneath the inclined inner side wall and outwardly beneath the inclined outer side wall of the groove, resulting in a better installation and accommodating a wider range of panel thicknesses. The V-shaped bottom wall also centers and balances the rolls during the rolling process resulting in a more accurate cross-section of the fastener.

Abstract: The self-attaching female fastener of this invention includes a re-entrant groove having a V-shaped bottom wall including relatively inclined bottom faces of equal width having an arcuate apex centered beneath the restricted opening to the groove. A die drives a panel portion through the restricted groove opening against the bottom faces, driving the panel portion into the apex and inwardly beneath the inclined inner side wall and outwardly beneath the inclined outer side wall of the groove, resulting in a better installation and accommodating a wider range of panel thicknesses. The V-shaped bottom wall also centers and balances the rolls during the rolling process resulting in a more accurate cross-section of the fastener.

Abstract: The disclosed fastener installation apparatus includes a plurality of spaced parallel feed passages each communicating with a plunger passage in a moveable member and the fixed member includes a plunger assembly having a plurality of spaced parallel legs which reciprocate through the plunger passages to simultaneously install a plurality of fasteners in a panel opposite the plunger passage. In one embodiment, the plunger assembly includes a body portion fixed to the fixed member and a plurality of integral parallel legs and a second embodiment having a plurality of separate spaced parallel plungers. Each plunger passage includes a proximity probe having an end adjacent to, but spaced from the plunger passage eliminating wear or damage to the proximity probes during use.

Abstract: A self-attaching nut having a central pilot projecting from an end face of the body portion, an annular groove surrounding the pilot and an annular panel support face surrounding the groove, wherein the outer side wall includes a plurality of circumferentially spaced notches, each having an outer wall which extends from the bottom wall of the annular groove to the panel support face and the bottom wall of the groove includes a plurality of circumferentially spaced radial ribs integral with either the outer or inner side walls of the annular groove having a radial end spaced from the opposed side wall and a top face inclined toward the bottom wall of the annular groove providing improved torque resistance and push-off strength. Alternating circumferentially overlapping radial ribs integral with the pilot and the outer groove wall and ribs which extend below the bottom wall of the groove are also disclosed.

Abstract: A self-attaching fastener installation head and feed mechanism including a spring-biased L-shaped feed pawl which feeds a first nut in the feed passage adjacent the plunger passage on the upstroke of the die press. The feed pawl is pivotally supported on a slide bracket which includes a roller in the longitudinal axis of the feed passage which is biased against a central cam surface on the base and the base is interconnected to the nose member by removable pins. A spring biased nut restrictor is pivotally supported on the nose member, simplifying removal of a nut strip from the head and the installation head is more rugged in design and has fewer parts, reducing costs.