Functional element, a component assembly consisting of a functional element and a sheet metal part and also a method for the attachment of the functional element to a sheet metal part

1. A functional element ( 10 ′; 10 ″) having a functional portion ( 16 ; 17 ; 17 ′), a generally tubular rivet portion and a ring-like sheet metal contact surface ( 22 ; 22 ′; 22 ″; 22 ″, 22 ′″, 22 ″″),

wherein features of shape ( 70 ; 70 , 70 ′; 90 ; 90 , 70 ) are provided at a free end of the rivet portion ( 20 ) away from the sheet metal contact surface, the features of shape being adapted to ensure co-movement of a sheet metal part ( 14 ) during the formation of a rivet bead and being provided at at least one of the free end ( 59 ) of the rivet portion and the radially outer side of the rivet portion ( 20 ), in the region adjacent the free end ( 59 ) of the rivet portion ( 20 ), wherein recesses ( 28 ) providing security against rotation are located in the region of the transition from the rivet portion ( 20 ) into a ring-like contact surface ( 22 , 22 ′; 22 ″) and are axially aligned with said features of shape provided at the free end of the rivet portion.

2. The functional element in accordance with claim 1 , wherein at least one of the following features of shape ( 70 ; 70 , 70 ′; 90 ; 90 , 70 ) is provided:

a) axially extending ribs ( 70 ; 70 , 70 ′) at the rivet portion, which extend at least from a region adjacent the contact surface ( 22 ; 22 ′; 22 ″; 22 ″, 22 ′″, 22 ″″) up to immediately before the free end ( 59 ) of the rivet portion ( 20 ),

b) locally raised portions ( 70 ′; 90 ) at the free end ( 59 ) of the rivet portion ( 20 ).

3. The functional element in accordance with claim 1 ,

wherein the functional element is a self-piercing element ( 10 ′; 10 ″) and is designed at the free end ( 59 ) of the rivet portion ( 20 ) for the piercing of a sheet metal part.

4. A functional element in accordance with claim 2 , wherein the features a) and b) are present,

wherein the raised portions ( 70 ′, 90 ) at the free end ( 59 ) of the rivet portion ( 20 ) are axially aligned with the axially extending ribs ( 70 ).

5. The functional element in accordance with claim 2 , wherein the features a) and b) are present and the raised portions ( 70 ′) are formed at the free end ( 59 ) of the rivet portion ( 20 ) by the ends of the radially extending ribs ( 70 ) which run out at the free end ( 59 ).

6. The functional element in accordance with claim 2 ,

wherein the ribs ( 70 ) in accordance with feature a) have a rounded shape in cross-section.

7. The functional element in accordance with claim 2 ,

wherein on realizing the feature b) the local raised portions ( 90 ) are at least approximately circular in plan view.

8. The functional element in accordance with claim 7 ,

wherein the raised portions ( 90 ) are of convex shape.

9. The functional element in accordance with claim 2 ,

wherein at least one of the axially extending ribs ( 70 ) in accordance with feature a) and the raised portions ( 70 ′; 90 ) in accordance with feature b) are uniformly distributed around the central longitudinal axis ( 24 ) of the functional element ( 10 ′; 10 ″).

10. The functional element in accordance with claim 2 ,

wherein the number of ribs ( 70 ) and the number of the raised portions ( 70 ′; 90 ) lies between 3 and 24.

11. The functional element in accordance with claim 1 ,

wherein cut-outs ( 28 ) are provided in a head part ( 18 ; 18 ′; 18 ″) or a flange region of the functional element ( 10 ′; 10 ″), project at least partly radially into the ring-like contact surface ( 22 ; 22 ′; 22 ″; 22 ″, 22 ′″; 22 ″″) open in the direction radially outwardly and have their largest cross-sectional dimensions at the radially outer surface of the head part ( 18 ; 18 ′; 18 ″).

12. The functional element in accordance with claim 1 ,

wherein the ring-like contact surface ( 22 ; 22 ′; 22 ″; 22 ″, 22 ′″; 22 ″″) is a conical surface apart from any noses ( 26 ; 26 ′; 28 ; 28 , 28 ′, 28 ″) providing, security against rotation and any cut-outs 28 .

13. The functional element in accordance with claim 1 ,

wherein the ring-like contact surface has at least one ring-like region which lies on a radial plane perpendicular to the central longitudinal axis ( 24 ) of the functional element.

14. The functional element in accordance with claim 1 ,

wherein a ring-like groove is provided radially inside the ring-like region of the ring-like contact surface, which lies in a radial plane perpendicular to the central longitudinal axis, with the groove extending around the rivet portion ( 20 ).

15. The functional element in accordance with claim 14 ,

wherein the ring-like groove has at the radially outer side a surface which is obliquely set relative to the central longitudinal axis, i.e. the groove is at least approximately V-shaped in cross-section.

16. The functional element in accordance with claim 14 ,

wherein ribs providing security against rotation, which extend in the radial direction, are provided in the ring-like groove and partly or completely bridge the latter.

17. The functional element in accordance with claim 16 ,

wherein cut-outs 28 , which interrupt the radially outer side of the ring-like groove and the ring-like region of the contact surface, are provided between the ribs providing security against rotation.

18. The functional element in accordance with claim 1 ,

wherein it is a bolt element ( 10 ′) having a shaft part ( 16 ).

19. The functional element in accordance with claim 18 ,

wherein a head part ( 18 ; 18 ′) is provided, with the tubular rivet portion ( 40 ) being provided on the one side of the head part ( 18 , 18 ′) and the shaft part ( 16 ) being provided on the other side of the head part ( 18 , 18 ′) and with the ring-like contact surface ( 22 ; 22 ′; 22 ″) being provided at the side of the bolt element ( 10 ′) facing the rivet portion ( 20 ).

20. The functional element in accordance with claim 18 ,

wherein a head section having the ring-like contact surface is provided; in that the shaft part of the bolt element is arranged at the same side of the head part as the ring-like contact surface and projects away from the latter and in that the tubular rivet portion ( 20 ) is provided radially within the ring-like contact surface and radially outside of the shaft part.

21. The functional element in accordance with claim 1 ,

wherein it is a nut element ( 10 ″).

22. The functional element in accordance with claim 21 ,

wherein a head section having the ring-like contact surface is provided which merges into a tubular hollow shaft part projecting from the head portion at the side of the contact surface, with the shaft part being surrounded by the tubular rivet portion ( 20 ), with the free end ( 59 ) of the shaft part being further removed from the ring-like contact surface than the free end ( 59 ) of the rivet portion ( 20 ).

23. The functional element in accordance with claim 22 ,

wherein the free end ( 59 ) of the shaft part is designed for piercing of a sheet metal part.

24. A functional element in accordance with claim 23 ,

wherein a thread is provided in the head section and also in the region of the shaft part adjacent the head section.