초록 ▼

The present disclosure relates to self-piercing fasteners, such as studs, bolts or nuts, the method of attaching such fasteners to a panel and fastener installation apparatus, including the installation head and die button. The fastener includes a self-piercing and riveting annular wall which is dri

The present disclosure relates to self-piercing fasteners, such as studs, bolts or nuts, the method of attaching such fasteners to a panel and fastener installation apparatus, including the installation head and die button. The fastener includes a self-piercing and riveting annular wall which is driven into a panel supported against a die member by the installation head. The die member includes an annular die cavity surrounding a central projecting die portion which is telescopically receivable in the free open end of the fastener annular wall. The free end of the fastener annular wall includes a piercing surface which mates with a piercing surface at the outer edge of the projecting die portion to pierce a slug from the panel. The panel slug is then pressed into the opening in the annular fastener wall by the conical end of the projecting die portion and the free end of the annular wall is simultaneously deformed radially outwardly in the die cavity forming a rigid mechanical interlock with the pierced panel edge.

대표청구항 ▼

1. A method of attaching a fastener to a plastically deformable panel, said fastener including a body portion and a self-piercing and riveting annular wall extending from said body portion, said annular wall having an outer surface, an inner surface, a free open end portion and a piercing surface ad

1. A method of attaching a fastener to a plastically deformable panel, said fastener including a body portion and a self-piercing and riveting annular wall extending from said body portion, said annular wall having an outer surface, an inner surface, a free open end portion and a piercing surface adjacent said inner wall surface and free end portion, said annular wall free end portion having an arcuate annular surface at said outer surface, the method comprising: (a) locating said fastener opposite said panel with said annular wall free end portion facing said panel and a die member located on the opposite side of said panel, said die member having an annular concave die cavity surrounding a projecting central die portion which is coaxially aligned with and telescopically receivable within said fastener annular wall opening; (b) engaging said panel with said fastener annular wall free end, said fastener arcuate surface deforming said panel into said annular concave die cavity; (c) said annular wall piercing surface piercing a slug from said panel and said central die portion receiving, supporting and centering said panel slug and carrying said slug into said annular wall opening; (d) plastically deforming said annular wall free end radially outwardly in said concave annular die cavity, forming said annular wall free end into an annular bead comprising a generally U-shaped channel in cross-section, said channel opening toward said fastener body portion and the pierced edge of said panel; and, (e) plastically deforming said pierced panel edge against said annular wall outer surface into said generally U-shaped channel, forming a mechanical interlock between said self-piercing and riveting annular wall and said panel. 2. The method of attaching a fastener to a panel as defined in claim 1, including piercing a panel slug from said panel having a width greater than the internal diameter of said annular wall opening and forcing said slug into said opening in engagement with said inner annular wall surface. 3. The method of attaching a fastener to a panel as defined in claim 2, including supporting said panel slug on said central die portion in binding engagement with said internal annular wall surface during said deformation of said annular wall free end, said panel slug supporting said annular wall and preventing collapse of said annular wall during said radial outward deformation. 4. The method of attaching a fastener to a panel as defined in claim 3, characterized in that the free end of said projecting central die portion is conical, having a relatively sharp apex, the method including deforming and doming said panel slug on said conical die surface free end, thereby centering and retaining said panel slug within said annular wall opening. 5. The method of attaching a fastener to a panel as defined in claim 1, characterized in that said fastener annular wall piercing surface is an angled annular chamfer face in the opening of said annular wall free end portion, the method including piercing a panel slug having a diameter greater than the internal diameter of said annular wall opening, then supporting said panel slug on said central die member portion in said annular wall opening generally at the point of the greatest internal stress resulting from said radial deformation of said annular wall. 6. The method of attaching a fastener to a panel as defined in claim 1, characterized in that said fastener body portion includes a base portion having a side surface and a bottom surface joined by an arcuate surface, said annular wall integrally joined to said base portion bottom surface spaced inwardly from said side surface, the method including driving said fastener base portion into said panel following piercing a slug from said panel, then simultaneously deforming said annular wall free end radially outwardly into said generally U-shaped channel and deforming the panel portion adjacent said pierced panel edge by counter rotating said panel portion within said fastener annular wall channel into a mechanical interlock wherein said panel portion substantially fills said fastener channel portion. 7. The method of attaching a fastener to a panel as defined in claim 1, including driving the panel portion adjacent said pierced panel edge into said annular wall U-shaped channel, deforming the free end of said pierced panel edge into said U-shaped channel, and forming a reinforcing enlarged annular bead on said pierced panel edge enclosed within and contacting the inner surface of said U-shaped channel. 8. The method of attaching a fastener to a panel as defined in claim 7, characterized in that said fastener includes a head portion having a radial flange extending outwardly generally perpendicular to and adjacent to said annular wall, the method including driving said fastener flange portion into said panel, thereby recessing said fastener in said panel and driving said pierced panel edge into said U-shaped channel of said annular wall. 9. The method of attaching a fastener to a panel as defined in claim 1, wherein said fastener is a female fastener having a bore, the method including driving said panel slug out of said annular wall opening after completion of the fastener and panel assembly. 10. The method of attaching a fastener to a panel as defined in claim 1, characterized in that said die member includes a plurality of flats defined on the outer surface of said concave die cavity, the method including deforming the panel adjacent said pierced panel edge radially inwardly by said die member flats providing anti-rotation means preventing rotation of said fastener relative to said panel following installation. 11. A method of attaching a fastener to a plastically deformable panel, said fastener including a body portion and a self-piercing and riveting annular wall extending from said body portion, said annular wall having an outer surface, an inner surface defining an opening and a free end portion, said annular wall having a piercing surface adjacent said inner surface spaced from the distal end of said free end portion, the method comprising: (a) locating said fastener opposite said panel with said annular wall free end portion facing said panel and a die member located on the opposite side of said panel, said die member having a concave die cavity surrounding a projecting central die portion, said central die portion having a generally conical free end portion coaxially aligned with and telescopically receivable within said fastener annular wall opening; (b) engaging said fastener annular wall free end portion against said panel and deforming said panel against said central die conical free end portion; (c) piercing a slug from said panel with said annular wall piercing surface, and said slug having a diameter greater than said fastener annular wall opening; (d) forcing said panel slug into said annular wall opening in firm engagement with said inner surface; and (e) plastically deforming said fastener annular wall free end portion radially outwardly in said die cavity and plastically deforming the pierced edge of said panel against said annular wall outer surface into engagement with the deformed end of said annular wall free end portion, thereby forming a mechanical interlock between said self-piercing and riveting annular wall and said pierced panel edge. 12. The method of attaching a fastener to a panel as defined in claim 11, characterized in that said fastener piercing surface is an annular chamfer face defining an outwardly inclined angle in said annular wall opening at said free end portion, the method including piercing a slug from said panel with said annular chamfer face, said slug having a diameter greater than said fastener annular wall opening. 13. The method of attaching a fastener to a panel as defined in claim 11, including deforming said fastener annular wall free end portion in said concave die cavity radially outwardly into a U-shaped channel in cross-section opening toward said fastener body portion and deforming said pierced panel edge into said U-shaped channel thereby forming said mechanical interlock. 14. The method of attaching a fastener to a panel as defined in claim 13, including driving said pierced panel edge into said U-shaped channel and deforming the free end of said pierced panel edge in said U-shaped channel and forming a reinforcing enlarged annular bead on said pierced panel edge. 15. A method of attaching a fastener to a metal panel, said fastener including a body portion and a self-piercing and riveting annular wall extending from said body portion, said annular wall having an outer surface, an inner surface, a free open end portion, and a piercing surface adjacent said free end portion and said inner surface, the method comprising: (a) locating said fastener opposite said panel with said annulas wall free end portion facing said panel and a die member located on the opposite side of said panel; (b) piercing a slug from said panel with said annular wall piercing surface; (c) said die member carrying said pierced panel slug into said annular wall opening; (d) plastically deforming said annular wall free end portion radially outwardly into a generally U-shaped channel with said channel opening toward said body portion and the pierced edge of said panel; (e) plastically deforming said pierced panel edge against said annular wall outer surface into said U-shaped channel, driving said pierced panel edge into said U-shaped channel, and plastically deforming the free end of said panel pierced edge and forming a reinforcing enlarged annular bead on said pierced panel edge enclosed within and contacting the inner surface of said U-shaped channel, thereby forming a reinforcing mechanical interlock between said self-piercing and riveting annular wall and said panel. 16. The method of attaching a fastener to a panel as defined in claim 15, characterized in that said annular wall piercing surface being spaced from said free end portion, said method including piercing a panel slug having a diameter greater than the internal diameter of said annular wall opening and forcing said slug into said opening in binding engagement with said internal surface, said panel slug supporting said inner wall surface and preventing collapse of said annular wall during deformation of said annular wall free end portion. 17. The method of attaching a fastener to a panel as defined in claim 16, characterized in that said die member includes a projecting central die portion coaxially aligned with and telescopically receivable within said annular wall opening, the free end of said central projecting die portion including a central conical surface having a relatively sharp apex, the method including deforming and doming said panel on said central conical surface free end, then piercing said panel and carrying said pierced panel slug into said annular wall opening in engagement with said inner surface, said relatively sharp central conical surface of said die member centering and retaining said panel slug in said annular wall opening. 18. The method of attaching a fastener to a panel as defined in claim 15, characterized in that said fastener body portion includes a radial flange extending outwardly generally perpendicular to said annular wall, said method including driving said flange portion into said panel, thereby recessing said fastener in said panel and driving said pierced panel edge free end into said U-shaped channel of said annular wall. 19. The method of attaching a fastener to a panel as defined in claim 15, chatacterized in that said fastener comprises a nut, said fastener body portion including a bore coaxially aligned with said annular wall, the method including driving said pierced panel slug out of said annular wall opening by driving a punch through said bore after completion of the nut and panel installation. 20. The method of attaching a fastener to a panel as defined in claim 15, characterized in that said fastener is a stud and said body portion includes an elongated shank portion having a longitudinal axis generally coaxilally aligned with said annular wall, and said body portion including a radial flange located between said shank portion and said annular wall, the method including driving said radial flange to pierce a slug from said panel with said piercing surface. 21. A method of attaching a nut fastener to a metal panel, said nut fastener having a body portion including a nut bore and a self-piercing and riveting annular wall projecting from said body portion, said annular wall having an opening through the free end portion generally coaxially aligned with said nut bore, the method comprising: (a) locating said nut fastener opposite said panel with said annular wall free end portion facing said panel and a die member located on the opposite side of said panel, said die member having an annular die cavity and a projecting central die portion coaxially aligned with and telescopically receivable within said annular wall opening; (b) piercing a slug from said panel with said annular wall free end portion and receiving and supporting said panel slug on said projecting central die portion; (c) displacing said panel slug into said annular wall opening and retaining said slug on said projecting central die portion in said opening; (d) plastically deforming said annular wall free end portion radially outwardly in said annular die cavity and plastically deforming the pierced edge of said panel into a mechanical interlock with said deformed annular wall free end; and, (e) punching said panel slug out of said annular wall opening. 22. The method of attaching a nut fastener to a panel as defined in claim 21, including deforming said annular wall free end into a generally U-shaped channel in cross-section with said channel opening toward said body portion and the pierced edge of said panel, and deforming said pierced panel edge against the outer surface of said annular wall into said U-shaped channel, thereby forming said mechanical interlock between said annular wall and said panel. 23. The method of attaching a nut fastener to a panel as defined in claim 22, including driving said pierced panel edge into said U-shaped channel, deforming the free end of said pierced panel edge in said U-shaped channel and forming a reinforcing enlarged annular bead on said pierced panel edge. 24. The method of attaching a nut fastener to a panel as defined in claim 21, wherein said nut fastener is driven towards said panel by a second die member including a driving member engaging said nut fastener body portion and said second die member having a bore telescopically aligned with said nut fastener bore and said second die member including a punch which is telescopically receivable through said second die member bore and said nut fastener bore, the method including telescopically driving said punch through said nut fastener bore, and driving said panel slug out of said annular wall opening after completion of said nut fastener and panel installation assembly. 25. A method of attaching a self-fastening member to a plastically deformable panel, said self-fastening member including a base portion having a side surface and a bottom surface, an annular wall integrally joined to said base portion bottom surface spaced inwardly from said base portion side surface, and said annular wall having a free open end portion, the method comprising: (a) locating said self-fastening member opposite said panel with said annular wall free end portion facing said panel and a die member located opposite said panel, said die member having an annular die cavity surrounding a central projecting die portion and said die member having a relatively flat panel supporting shoulder on opposite sides of said die cavity, the free end of said central die portion coaxially aligned with and telescopically receivable in said self-fastening member annular wall free open end portion and said central die portion free end spaced below the plane of said die member shoulder, said central die portion having a relatively smooth arcuate concave outer die surface extending through the bottom surface of said die cavity, and the outer surface of said annular die cavity including an inwardly inclined die surface extending from adjacent said shoulder into said die cavity and terminating in an annular lip spaced above said die cavity bottom surface; (b) supporting said panel on said die member shoulder in fixed relation; and, (c) relatively moving said self-fastening member and said die member toward each other to perform the following method steps in a continuous operation; (1) engaging said panel with said self-fastening member annular wall free end and piercing said fastener free end through said panel and plastically deforming said panel into said annular die cavity, (2) telescopically disposing said central die portion into said annular wall free open end portion through an opening pierced in said panel, (3) plastically deforming said self-fastening member annular wall free end radially outwardly against said die member central portion arcuate concave outer die surface, and plastically deforming the panel portion adjacent said opening into said die cavity against the outer surface of said annular wall, and (4) plastically deforming said self-fastening member annular wall free end radially outwardly into a U-shaped channel in cross-section opening toward said member base portion through said die cavity bottom surface and simultaneously driving said self-fastening member base portion into said panel and counter rotating said panel portion in the developing U-shaped channel of said annular wall free end, forming a mechanical interlock between said annular wall and said panel portion. 26. The method of attaching a self-fastening member to a panel as defined in claim 25, characterized in that said self-fastening member annular wall free open end includes a piercing surface, the method including piercing a slug from said panel, thereby forming said panel opening, and displacing said pierced panel slug into said annular wall opening on said die member central portion, as the members move together, locating said panel slug at generally the point of greatest stress as said annular wall is deformed radially outwardly. 27. The method of attaching a self-fastening member to a panel as defined in claim 26, characterized in that said piercing surface is an annular chamfer face defined at an outwardly inclined angle to the inner surface of said annular wall free end, the method including piercing a slug from said panel having a diameter greater than the internal diameter of said annular wall and forcing said slug into said annular wall open free end in binding engagement with said annular wall inner surface.