Connection Element and Method for Producing a Connection Element

Abstract

A connection element, in particular a setting bolt, for connecting at least two components, in particular metal sheet components, is disclosed. The connection element has a tapered region and a shaft region, the properties of which are different. The connection element is formed as one piece. A method for producing a connection element is also disclosed.

Claims

1.-8. (canceled)

9. A connection element for connecting two components, comprising: a tapered region; and a shaft region, wherein properties of the tapered region and the shaft region are different; wherein the connection element is formed as one piece.

10. The connection element according to claim 9, wherein the connection element is a setting bolt and wherein the two components are metal sheet components.

11. The connection element according to claim 9, wherein the tapered region has a greater strength than the shaft region.

12. The connection element according to claim 9, wherein the tapered region has a sliding coating and wherein the shaft region has an adhesive coating.

13. The connection element according to claim 9, wherein the tapered region has a lower surface roughness than the shaft region.

14. A method for producing a connection element for connecting two components, wherein the connection element has a tapered region and a shaft region with different properties, comprising the step of: producing the connection element as one piece.

15. The method according to claim 14, wherein the connection element is a setting bolt and wherein the two components are metal sheet components.

16. The method according to claim 14, further comprising the step of laser curing or inductive curing the tapered region.

17. The method according to claim 16, further comprising the step of tempering the tapered region after the laser curing or inductive curing.

18. The method according to claim 14, further comprising the steps of providing an entirety of the connection element with an adhesive coating followed by removing the adhesive coating only in the tapered region in a first immersion bath and then followed by providing the tapered region with a sliding coating in a second immersion bath.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0014] FIG. 1 is a schematic side view of a connection element formed as a setting bolt, wherein a tapered region of the connection element has a higher strength than the shaft region of the connection element; and

[0015] FIG. 2 is a further schematic side view of the connection element formed as a setting bolt, wherein a sliding coating applied in the tapered region and an adhesive coating applied in the shaft region are made clear.

DETAILED DESCRIPTION OF THE DRAWINGS

[0016] In the figures, the same or functionally identical elements are provided with the same reference numerals.

[0017] A connection element 10 in the form of a setting bolt is shown in FIG. 1 in a schematic side view. The connection element 10 comprises a tapered region 12 and a shaft region 14, wherein a head region 16 of the connection element 10 is assumed for the following embodiments as belonging to the shaft region 14.

[0018] The connection element 10 is thus formed to be pin-shaped and is also usually referred to as a so-called tack. The connection element 10 can be driven into respective components, in particular metal sheets, with high speed by means of a setting device not depicted here such that the two components, in particular metal sheets, are joined to each other by means of the connection element 10. Depending on the material properties of the metal sheets to be joined, different demands are also made of the connection element 10 such that the metal sheets can be reliably joined to each other with a correspondingly high holding force.

[0019] In order to be able to penetrate high-strength metal sheets, for example, it is necessary that the tapered region 12 has a particularly great hardness since the tapered region 12 is otherwise plastically deformed when penetrating the high-strength metal sheets. Thus, it is provided that the tapered region 12 has a higher strength than the shaft region 14. For example, the tapered region 12 can have a strength of at least 2,000 MPa, wherein the shaft region 14 has a maximum strength of 1,500 MPa. For this, the tapered region 12 can be laser-cured or inductively cured, for example, during production of the connection element 10, wherein the tapered region 12 is preferably still tempered after the laser curing or inductive curing.

[0020] Due to the fact that only the tapered region 12 is cured or tempered, susceptibility to hydrogen embrittlement of the shaft region 14 is avoided. In other words, the tapered region 12 has a very great hardness such that even ultra high-strength steels, for example made of Usibor, for example, can be reliably penetrated by the tapered region 12 without a plastic deformation of the tapered region 12. The shaft region 14 is thus still soft enough to ensure that it is not susceptible to hydrogen embrittlement.

[0021] Alternatively, it would also be possible for different materials to be combined for the shaft region 14 and the tapered region 12, wherein the tapered region can be produced from a very strong material and the shaft region 14 from a relatively soft material.

[0022] In particular when metal sheets with a relatively low stiffness are to be joined by means of the connection element 10, it is important that the tapered region 12 has a relatively low friction value such that the tapered region 12 can reliably penetrate the metal sheets.

[0023] However, in order to be able to ensure an adequate holding force or strength of the joining connection produced by the metal sheets, it is important that the shaft region 14 has a correspondingly high friction.

[0024] In FIG. 2, the connection element 10 is shown in a further schematic side view. As schematically indicated in FIG. 2, the tapered region 12 has a sliding coating 18 and the shaft region 14 an adhesive coating 20. When producing the connection element 10, firstly the whole connection element 10 is provided with the adhesive coating 20. Subsequently, only in the tapered region 12, which is then also provided with the adhesive coating 20, the adhesive coating 20 is removed in a first immersion bath and then only the tapered region 12 is provided with the sliding coating 18 in a second immersion bath. Because of the sliding coating 18, the connection element 10 with its tapered region 12 slides particularly easily into a material having a low stiffness, in particular. Because of the adhesive coating 20, a high friction between the shaft region 14 and the metal sheets to be joined to one another is nevertheless ensured such that a high holding force or strength of the joining connection produced by means of the connection element 10 can be ensured.

[0025] Alternatively or additionally, it can also still be provided that the tapered region 12 has a lower surface roughness than the shaft region 14. This can be obtained, for example, by a corresponding mechanical processing of the tapered region 12 or of the shaft region 14. As a result, it is also possible to securely join, in particular, metal sheets with a relatively low stiffness by means of the connection element 10. Due to the relatively low surface roughness of the tapered region 12 compared to the shaft region 14, the tapered region 12 penetrates very easily into corresponding metal sheet parts with a low stiffness, wherein, because of the increased surface roughness of the shaft region 14, it correspondingly strongly rubs on the metal sheets joined to one another and thus a high holding force in the produced joining connection can be obtained.

[0026] The connection element 10 thus has locally specific different properties in terms of its hardness and/or coating. Thus, materials both with a high yield strength and materials with a low stiffness can be reliably joined by means of the connection element 10. The respective functional regions 12, 14 of the connection element 10 thus have the optimal properties depending on the metal sheets to be joined. No compromise has to made in terms of the material properties and the coating properties, instead, in each case the optimal properties can be specifically obtained during production of the connection element 10.

[0027] The present invention is not limited to connecting at least two components, in particular metal sheet components. Components made of cast iron or other materials can also be joined to one another by means of the connection element 10 according to the invention.