Method of forming a nut and panel assembly

Claim 1

A method of affixing a flanged nut to a heavy gauge panel, with the pilot of the nut substantially flush in the panel, said nut having a rectangular pilot portion with opposed end walls, a pair of flanges extending laterally from opposed side walls of said pilot portion, adjacent one end of said pilot portion, an undercut groove in each of said side walls of the pilot portion defining a pair of relatively massive piercing shoulders adjacent a flat piercing face of said pilot portion, said undercut grooves having side walls inclined relative to said piercing face to define said massive piercing shoulders and terminating generally vertically beneath said massIve piercing shoulders, said piercing shoulders overlying said flange portions, and a groove in each of said flanges having a generally flat bottom surface which is generally parallel to said flat piercing face and intersecting a respective inclined side wall of the undercut groove to form an obtuse angle therebetween, said nut further having substantially flat end walls perpendicular to said piercing face, said panel having a thickness at least equal to the height of said pilot portion measured from said flange portions to said piercing face of said pilot portion, comprising, in a single step, the operation of impacting the heavy gauge panel with said rectangular flat piercing face of the nut to punch an opening in the panel receiving the pilot portion therein and removing a slug from the panel, deforming the pierced edge of the panel, adjacent said opening in the panel, beneath said piercing shoulders and into said undercut grooves and against said pilot portion side walls and, without deforming the piercing shoulders overlying said undercut grooves, and continuing to deform and extruding said panel edge into said undercut grooves and then into said flange grooves, confining said pierced panel edge beneath said massive piercing shoulders and within said grooves and reducing the width of said pierced panel edge to define a channel-shaped groove adjacent and parallel to said piercing shoulders, such that the pilot piercing face is substantially flush with the panel and the nut is securely retained in the panel opening, and deforming the end walls of the nut to define laterally extending clinching portions overlying said panel on the same side as said flanges.

Claim 2

A method of affixing a flanged nut to a heavy gauge panel, with the pilot of the nut substantially flush in the panel, said nut having a rectangular pilot portion with opposed end walls, a pair of flanges extending laterally from opposed side walls of said pilot portion, adjacent one end of said pilot portion, an undercut groove in each of said side walls of the pilot portion defining a pair of relatively massive piercing shoulders adjacent a flat piercing face of said pilot portion, said undercut grooves having side walls inclined relative to said piercing face to define said massive piercing shoulders and terminating generally vertically beneath said massIve piercing shoulders, said piercing shoulders overlying said flange portions, and a groove in each of said flanges having a generally flat bottom surface which is generally parallel to said flat piercing face and intersecting a respective inclined side wall of the undercut groove to form an obtuse angle therebetween, said nut further having substantially flat end walls perpendicular to said piercing face, said panel having a thickness at least equal to the height of said pilot portion measured from said flange portions to said piercing face of said pilot portion, comprising, in a single step, the operation of impacting the heavy gauge panel with said rectangular flat piercing face of the nut to punch an opening in the panel receiving the pilot portion therein and removing a slug from the panel, deforming the pierced edge of the panel, adjacent said opening in the panel, beneath said piercing shoulders and into said undercut grooves and against said pilot portion side walls and, without deforming the piercing shoulders overlying said undercut grooves, and continuing to deform and extruding said panel edge into said undercut grooves and then into said flange grooves, confining said pierced panel edge beneath said massive piercing shoulders and within said grooves and reducing the width of said pierced panel edge to define a channel-shaped groove adjacent and parallel to said piercing shoulders, such that the pilot piercing face is substantially flush with the panel and the nut is securely retained in the panel opening, and deforming the end walls of the nut to define laterally extending clinching portions overlying said panel on the same side as said flanges.

Claim 5

A method of forming a nut and panel assembly, said nut having a rectangular pilot and a flat piercing face, a pair of opposed flanges extending laterally from inclined side walls of said pilot, adjacent one end, and panel receiving undercut grooves formed by said inclined side walls defining relatively massive piercing shoulders overlying said flanges, a groove in each of said flanges having a flat bottom surface and being generally parallel to said flat piercing face and intersecting a respective inclined side wall of said pilot undercut groove to form an obtuse angle therebetween the end walls of said pilot portion being generally flat, including the steps of: disposing a heavy gauge panel between said nut pilot and a die, said die having a central rectangular opening, said opening corresponding in size to the width of said nut as measured between the piercing shoulders, and being smaller than the transverse dimension of said nut as measured between said end walls, moving said die, relative to said heavy gauge panel and nut, causing said shoulders to shear the panel, and continuing to move said die, relative to said panel and nut, to (1) pierce a slug from said panel, (2) deform the pierced panel edges into said undercut grooves and then extruding the panel material into said flange grooves, (3) closely receive said piercing shoulders of said nut pilot within said die opening, (4) deform and extrude portions of said end walls of said pilot portion toward the plane of said flanges, and (5) extrude said deformed pilot end walls to define laterally extending clinching portions overlying said panel on the same side as sAid flanges, all in one stroke of the die.

Claim 6

A method of forming a nut and panel assembly, said nut having a rectangular pilot and a flat piercing face, a pair of opposed flanges extending laterally from inclined side walls of said pilot, adjacent one end, and panel receiving undercut grooves formed by said inclined side walls defining relatively massive piercing shoulders overlying said flanges, a groove in each of said flanges having a flat bottom surface and being generally parallel to said flat piercing face and intersecting a respective inclined side wall of said pilot undercut groove to form an obtuse angle therebetween the end walls of said pilot portion being generally flat, including the steps of: disposing a heavy gauge panel between said nut pilot and a die, said die having a central rectangular opening, said opening corresponding in size to the width of said nut as measured between the piercing shoulders, and being smaller than the transverse dimension of said nut as measured between said end walls, moving said die, relative to said heavy gauge panel and nut, causing said shoulders to shear the panel, and continuing to move said die, relative to said panel and nut, to (1) pierce a slug from said panel, (2) deform the pierced panel edges into said undercut grooves and then extruding the panel material into said flange grooves, (3) closely receive said piercing shoulders of said nut pilot within said die opening, (4) deform and extrude portions of said end walls of said pilot portion toward the plane of said flanges, and (5) extrude said deformed pilot end walls to define laterally extending clinching portions overlying said panel on the same side as sAid flanges, all in one stroke of the die.

Claim 10

A method of securing a self-piercing nut to a heavy gauge panel, said nut having a rectangular pilot, a bore extending through said pilot and having an axis, said pilot having a substantially flat rectangular piercing face perpendicular to said bore axis, a pair of flanges extending laterally from said pilot adjacent the end of said pilot remote from said piercing face and spaced from said piercing face by the side walls of said pilot, grooves undercut in said side walls of the pilot defining relatively massive shoulders overlying said flanges, said side wall grooves terminating generally vertically beneath said massive piercing shoulders, the end walls of said pilot, perpendicular to said side walls, being generally flat and said relatively massive shoulders being longer than said end walls at said piercing face, as measured perpendicular to the bore axis, and a groove in each of said flanges having a flat bottom surface being generally parallel to said flat piercing face and intersecting respective side wall grooves vertically beneath said massive piercing shoulders, including the steps of: disposing a heavy gauge panel between said piercing face of the nut and a die having a square opening, the length of the sides of said square opening being substantially equal to the length of said pilot shoulders, moving said die towards said nut and panel to shear a square opening in said panel, and continuing to move said die, relative to said nut and panel, to force said rectangular pilot into said square opening and closely receive said piercing shoulders therein, deforming and extruding said end walls of the pilot toward said flanges and forming a pair of clinching lips overlying said panel, on the same side of the panel material as said flanges, and deforming and extruding the pierced edges of said panel beneath said shoulders and into said undercut grooves and then against said flat bottom surfaces of said flange grooves to securely retain the nut on the panel.

Claim 11

A method of securing a self-piercing nut to a heavy gauge panel, said nut having a rectangular pilot, a bore extending through said pilot and having an axis, said pilot having a substantially flat rectangular piercing face perpendicular to said bore axis, a pair of flanges extending laterally from said pilot adjacent the end of said pilot remote from said piercing face and spaced from said piercing face by the side walls of said pilot, grooves undercut in said side walls of the pilot defining relatively massive shoulders overlying said flanges, said side wall grooves terminating generally vertically beneath said massive piercing shoulders, the end walls of said pilot, perpendicular to said side walls, being generally flat and said relatively massive shoulders being longer than said end walls at said piercing face, as measured perpendicular to the bore axis, and a groove in each of said flanges having a flat bottom surface being generally parallel to said flat piercing face and intersecting respective side wall grooves vertically beneath said massive piercing shoulders, including the steps of: disposing a heavy gauge panel between said piercing face of the nut and a die having a square opening, the length of the sides of said square opening being substantially equal to the length of said pilot shoulders, moving said die towards said nut and panel to shear a square opening in said panel, and continuing to move said die, relative to said nut and panel, to force said rectangular pilot into said square opening and closely receive said piercing shoulders therein, deforming and extruding said end walls of the pilot toward said flanges and forming a pair of clinching lips overlying said panel, on the same side of the panel material as said flanges, and deforming and extruding the pierced edges of said panel beneath said shoulders and into said undercut grooves and then against said flat bottom surfaces of said flange grooves to securely retain the nut on the panel.

Claim 12

A method of securing a self-piercing nut to a heavy gauge panel, said nut having a rectangular pilot, a bore extending through said pilot and having an axis, said pilot having a substantially flat rectangular piercing face perpendicular to said bore axis, a pair of flanges extending laterally from said pilot adjacent the end of said pilot remote from said piercing face and spaced from said piercing face by the side walls of said pilot, grooves undercut in said side walls of the pilot defining relatively massive shoulders overlying said flanges, said side wall grooves terminating generally vertically beneath said massive piercing shoulders, the end walls of said pilot, perpendicular to said side walls, being generally flat and said relatively massive shoulders being longer than said end walls at said piercing face, as measured perpendicular to the bore axis, and a groove in each of said flanges having a flat bottom surface being generally parallel to said flat piercing face and intersecting respective side wall grooves vertically beneath said massive piercing shoulders, including the steps of: disposing a heavy gauge panel between said piercing face of the nut and a die having a square opening, the length of the sides of said square opening being substantially equal to the length of said pilot shoulders, moving said die towards said nut and panel to shear a square opening in said panel, and continuing to move said die, relative to said nut and panel, to force said rectangular pilot into said square opening and closely receive said piercing shoulders therein, deforming and extruding said end walls of the pilot toward said flanges and forming a pair of clinching lips overlying said panel, on the same side of the panel material as said flanges, and deforming and extruding the pierced edges of said panel beneath said shoulders and into said undercut grooves and then against said flat bottom surfaces of said flange grooves to securely retain the nut on the panel.

Claim 13

A method of securing a self-piercing nut to a heavy gauge panel, said nut having a rectangular pilot, a bore extending through said pilot and having an axis, said pilot having a substantially flat rectangular piercing face perpendicular to said bore axis, a pair of flanges extending laterally from said pilot adjacent the end of said pilot remote from said piercing face and spaced from said piercing face by the side walls of said pilot, grooves undercut in said side walls of the pilot defining relatively massive shoulders overlying said flanges, said side wall grooves terminating generally vertically beneath said massive piercing shoulders, the end walls of said pilot, perpendicular to said side walls, being generally flat and said relatively massive shoulders being longer than said end walls at said piercing face, as measured perpendicular to the bore axis, and a groove in each of said flanges having a flat bottom surface being generally parallel to said flat piercing face and intersecting respective side wall grooves vertically beneath said massive piercing shoulders, including the steps of: disposing a heavy gauge panel between said piercing face of the nut and a die having a square opening, the length of the sides of said square opening being substantially equal to the length of said pilot shoulders, moving said die towards said nut and panel to shear a square opening in said panel, and continuing to move said die, relative to said nut and panel, to force said rectangular pilot into said square opening and closely receive said piercing shoulders therein, deforming and extruding said end walls of the pilot toward said flanges and forming a pair of clinching lips overlying said panel, on the same side of the panel material as said flanges, and deforming and extruding the pierced edges of said panel beneath said shoulders and into said undercut grooves and then against said flat bottom surfaces of said flange grooves to securely retain the nut on the panel.