초록 ▼

A self-piercing rivet of a special rivet geometry is described, which in particular is suitable for joining high strength steel sheets, but can also be used for other metal sheets. The self-piercing rivet is in particular characterized by a special underhead geometry as well as a special geometry of

A self-piercing rivet of a special rivet geometry is described, which in particular is suitable for joining high strength steel sheets, but can also be used for other metal sheets. The self-piercing rivet is in particular characterized by a special underhead geometry as well as a special geometry of the rivet foot (cutting region). Thus the self-piercing rivet has an underhead chamfer which with a radial plane of the self-piercing rivet encloses an angle of 20°+5°/-5° and merges tangentially into the cylindrical outer surface of the rivet shank via a radius. In the region of the rivet foot the self-piercing rivet has a plane shank face, which extends essentially at a right angle to the rivet axis and which merges "smoothly" into the cylindrical inner surface via a shank inner surface and a radius. In comparison to conventional self-piercing rivets the special rivet geometry enables lower joining forces and tensile forces in the joining operation, an optimized load bearing performance and an optimum joint quality of the self-piercing rivet joint as well as minimum gap formation between the rivet and the metal sheet.

대표청구항 ▼

We claim: 1. A self-piercing rivet comprising a rivet head and a rivet shank with a central shank hole, which are all designed so as to be rotationally symmetrical with reference to a central axis, wherein the rivet head has a top side and a cylindrical head exterior surface of a predetermined head

We claim: 1. A self-piercing rivet comprising a rivet head and a rivet shank with a central shank hole, which are all designed so as to be rotationally symmetrical with reference to a central axis, wherein the rivet head has a top side and a cylindrical head exterior surface of a predetermined head diameter, the rivet shank having an essentially cylindrical shank exterior surface and a cylindrical shank interior surface limiting the central shank hole, the head exterior surface and shank exterior surface being joined by a conical underhead chamfer and an underhead radius, which merges tangentially into the conical underhead chamfer and the shank exterior surface, wherein the conical underhead chamfer and a radial plane of the self-piercing rivet include an angle of 20°+5°/-5°, and the shank exterior surface and shank interior surface at the axial end remote from the rivet head being joined by a plane shank face, a conical shank inside chamfer and a shank end radius, of which the shank end radius merges tangentially into the shank interior surface and the conical shank inside chamfer, and the plane shank face is joined with the shank exterior surface by a cutting surface, the plane shank face and a radial plane of the self-piercing rivet including an angle of 0-3°/+3° and the conical shank inside chamfer and a radial plane of the self-piercing rivet including an angle of 45°+10°/-5°. 2. The self-piercing rivet according to claim 1, wherein the radial width of the plane shank face is greater than 0.035 times the diameter of the shank exterior surface. 3. The self-piercing rivet according to claim 1, wherein the underhead radius is smaller than 0.30 times the diameter of the shank exterior surface. 4. The self-piercing rivet according to claim 1, wherein the cutting surface between the plane shank face and the shank exterior surface has a radial width of less than 0.1 mm. 5. The self-piercing rivet according to claim 1, wherein the head diameter is 7.75 mm+0.15 mm/-0.15 mm, the diameter of the shank exterior surface is 5.3 mm+0.1 mm/-0.15 mm, and the radial width of the plane shank face is 0.35 m+0.10 mm/-0.15 mm. 6. The self-piercing rivet according to claim 5, wherein the underhead radius is 0.67 mm+0.10 mm/-0.10 mm. 7. The self-piercing rivet according to claim 5, wherein the shank end radius is 0.70 mm+0.1 mm/-0.1 mm. 8. The self-piercing rivet according to claim 5, wherein the diameter of the shank interior surface is 3.40 mm+0.3 mm/-0.00 mm. 9. The self-piercing rivet according to claim 5, wherein the axial height of the head exterior is 0.40 mm+0.00 mm/-0.40 mm. 10. The self-piercing rivet according to claim 1, wherein it is a semihollow self-piercing rivet, the central hole being a blind hole. 11. The self-piercing rivet according to claim 10, wherein the hole bottom of the central hole exhibits a central radius and two lateral transition radii, of which the two transition radii each tangentially merge into the central radius and an adjoining shank inside wall. 12. The self-piercing rivet according to claim 10, wherein the central radius of the hole bottom is greater than 1.00 times the diameter of the shank exterior surface. 13. The self-piercing rivet according to claim 10, wherein a central radius of the hole bottom is 6.01 mm+0.10 mm/-0.10 mm. 14. The self-piercing rivet according to claim 13, wherein the two lateral transition radii of the hole bottom are 0.27 mm+0.05 mm/-0.05 mm. 15. The self-piercing rivet according to claim 10, wherein the axial height of the rivet head on the central axis is less than 1.00 mm. 16. The self-piercing rivet according to claim 1, wherein it is designed as a hollow self-piercing rivet, the central hole being a through hole. 17. The self-piercing rivet according to claim 16, wherein the shank interior surface is essentially designed cylindrically over the entire length of the central hole. 18. The self-piercing rivet according to claim 16, wherein the shank interior surface on the head end of the self-piercing rivet merges into an extension. 19. The self-piercing rivet according to claim 18, wherein the extension exhibits a conical extension surface. 20. The self-piercing rivet according to claim 19, wherein the conical extension merges into the shank interior surface via a corner or a radius.