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 die set assembly for attaching a fastener to a plastically deformable panel, comprising: a self-attaching fastener and an opposed piercing die member, said fastener having a body portion and an annular self-piercing and riveting annular wall extending from said body portion, said annular wall h

1. A die set assembly for attaching a fastener to a plastically deformable panel, comprising: a self-attaching fastener and an opposed piercing die member, said fastener having a body portion and an annular self-piercing and riveting annular wall extending from said body portion, said annular wall having an outer surface, an inner surface, a free end portion having an opening therethrough and a piercing surface adjacent said free end and said inner wall, said die member including an annular die cavity surrounding a projecting central die portion and a panel supporting shoulder on at least two sides of said die cavity, the free end of said projecting die portion having a central conical surface facing said annular wall opening and a piercing surface surrounding said conical surface at the outer edge of said projecting die portion free end, said die member piercing surface of the same general configuration and generally mating with said fastener annular wall piercing surface, said projecting die portion free end coaxially aligned with and telescopically receivable within said annular wall opening, said annular die cavity having an inclined die surface adjacent said die piercing edge which receives said fastener annular wall free end portion inner surface spaced from the bottom of said cavity, a second die member for moving said self-attaching fastener relative to said die member to pierce a slug from a panel supported on said die shoulder between said mating piercing surfaces and said panel slug being received, supported and aligned on said conical surface of said projecting die portion in said annular wall opening, and said annular die cavity deforming said fastener annular wall free end radially outwardly, forming a mechanical interlock with the pierced edge of said panel. 2. The die set assembly, as defined in claim 1, characterized in that said central projecting die portion is integral with said die member and said conical surface is spaced below the plane of said shoulder, such that said panel is first deformed from the plane of said shoulder into engagement with said conical die surface and domed prior to piercing a slug from said panel. 3. The die set assembly, as defined in claim 2, characterized in that the outer surface of said annular wall free end is arcuate to deform said panel into said die opening without piercing, until said piercing surfaces mate. 4. The die set assembly, as defined in claim 1, characterized in that said annular fastener wall piercing surface is an annular chamfer at the opening of said annular wall free end portion defined at an outwardly inclined angle to the longitudinal axis of said annular wall, such that the slug pierced from said panel has a greater diameter than the internal diameter of said annular wall opening. 5. The die set assembly, as defined in claim 1, characterized in that said annular wall opening has a bottom wall spaced from said fastener annular wall free end and said die member conical surface is adapted to deform said panel slug against said bottom wall to securely retain said slug in said opening. 6. The die set assembly, as defined in claim 5, characterized in that said bottom wall is conical and convex to deform said panel slug radially outwardly into firm binding engagement with said annular wall inner surface. 7. The die set assembly, as defined in claim 1, characterized in that said die member projecting portion free end includes a flat annular surface surrounding said conical surface and said die member piercing surface is a sharp edge defined by the outer edge of said flat annular surface and said inclined inner surface of said annular die cavity which are generally at right angles. 8. The die set assembly, as defined in claim 1, wherein said second die member includes a shoulder engaging said fastener body and moveable relative to said piercing die member to drive said fastener into engagement with said panel. 9. The die set assembly, as defined in claim 8, characterized in that said fastener comprises a nut having a bore through said body portion generally coaxially aligned with said annular wall and said second die member includes a bore coaxially aligned with said nut bore, and said second die member including a punch telescopically receivable through said nut and second die member bore to punch said panel slug out of said annular wall opening after completion of the assembly. 10. A die set assembly including a die member for securing a self-attaching fastener to a plastically deformable panel, said fastener having a body portion and a self-piercing and riveting annular wall projecting from said body portion including a piercing surface adjacent an inner surface of said annular wall, said die member comprising a body portion having an annular concave die cavity surrounding a central die portion projecting from said die cavity and a panel supporting shoulder located on at least two sides of said die set assembly including a die cavity, the free end of said central die portion including a central conical die surface and a relatively sharp piercing edge surrounding said conical die surface at the outer edge of said central die portion free end, said piercing die edge adapted to generally mate with said fastener piercing surface to pierce a slug from a panel supported on said die shoulder, and said shoulder blending into said annular concave die cavity in an inclined surface for receiving the panel as the panel is deformed into said die cavity during installation and a second member for moving said self attaching fastener relative to said die member to pierce a slug from a panel supported on said die shoulder, and to deform said fastener annular wall free end radially outwardly by contact with said annular die cavity to form a mechanical interlock with a pierced edge of said panel. 11. The die member as defined in claim 10, characterized in that said central die portion free end includes a generally flat annular surface surrounding said conical surface and said die member piercing edge is defined by the outer edge of said annular surface and the generally perpendicular inner surface of said annular die cavity. 12. The die member as defined in claim 10, characterized in that said central die portion is integral with said die member body portion and said concial die surface is spaced below said shoulder, such that the panel is first deformed from the plane of said shoulder into engagement with said conical die surface prior to piercing a slug from said panel. 13. The die member as defined in claim 12, characterized in that said annular concave die cavity is semi-toroidal having a smooth arcuate surface on said central die portion for receiving the free end of said annular wall and deforming the annular wall radially outwardly to form a mechanical interlock between the pierced edge of said panel and the deformed end of said annular fastener wall.