WO2017220236A1

WO2017220236A1 - Blind rivet and rivet connection

Info

Publication number: WO2017220236A1
Application number: PCT/EP2017/059872
Authority: WO
Inventors: Nathanael Sutter
Original assignee: Bayerische Motoren Werke Aktiengesellschaft
Priority date: 2016-06-22
Filing date: 2017-04-26
Publication date: 2017-12-28
Also published as: DE102016211104A1

Abstract

The invention relates to a blind rivet (10) having a rivet sleeve (12), comprising a rivet head (18) for contacting on a workpiece (50) and a rivet mandrel (20) penetrating through the rivet sleeve (12) and having a mandrel shaft (22) with a mandrel head (26) as well as a rivet connection using the blind rivet (10). A ring (30) is placed on the mandrel shaft (22) between the rivet sleeve (12) and the mandrel head (26), which is designed in such a way that the ring (30) can be moved outwards from a first position into a second position via a retraction movement (p) of the rivet mandrel (20) relative to the rivet sleeve (12), wherein a previously exposed outer surface of the ring (30) comes into contact with the mandrel head (26) and an annular contact surface for the sleeve shaft (14) is provided, which is increased relative to the first position, and which projects radially above the mandrel head (26).

Description

description

Blind rivet and riveted joint

The invention relates to a collar rivet and a rivet connection using the blind rivet.

Blind rivets, which are also called Zugdornniete, are well known in the art. A blind rivet usually consists of a hollow rivet sleeve with a rivet head and an opposite end and a rivet mandrel guided through the rivet sleeve with a mandrel shaft and a mandrel head.

Blind rivets are preferably used if only one-sided component accessibility is given. When riveting the blind rivet is placed with the rivet head on the components to be joined, the rivet and the rivet mandrel pass through the components. By means of a riveting tool, the rivet head, also referred to as a setting head, is pressed onto the components and the rivet mandrel projecting from the rivet head is pulled back or out with the riveting tool. The mandrel head of the rivet mandrel causes a deformation force on the rivet sleeve, whereby the rivet sleeve is compressed and deformed to form a closing head, which is supported on the component side opposite the rivet head. Such a blind rivet is often designed as a breakaway blind rivet, wherein the rivet mandrel is provided with a predetermined breaking point, which breaks during the riveting operation.

A Dornbruchblindniet is known for example from the document WO 00/68583. In order to realize different clamping regions, the mandrel shaft of this blind rivet is designed to be non-deformable, and the sleeve shaft has a deformation region extending in the longitudinal direction of the sleeve, which is designed in such a way that at different lengthwise positions. On the deformation area, a closing head can be formed by sleeve folding.

Furthermore, it is known to form the closing head by widening or spreading the end of the rivet sleeve. For example, shows the printing step DE 10 2013 020 801 AI in which a riveted joint between two components is formed by the fact that by a relative movement of the Zugschafts to a Fließformniethülse this expanded in a first edge region and is brought into abutment with the one component. A second edge region is bent over to the other component by means of a forming tool surrounding the pull shaft and brought into abutment with the other component.

The object of the invention is to provide an alternative blind rivet, with which a high-strength component connection can be achieved and a corresponding high-strength rivet connection.

The problem is solved by a blind rivet according to claim 1 and a rivet connection according to claim 10.

The blind rivet according to the invention comprises a rivet sleeve with a rivet head for engagement with a component and a rivet mandrel penetrating the rivet sleeve with a mandrel shaft with mandrel head. Between the rivet sleeve and the mandrel head, a ring is fitted on the mandrel shaft, which is designed so that the ring can be transferred by a retraction movement of the rivet mandrel relative to the rivet sleeve from a first position to a second position to the outside, with a previously exposed outer surface of the ring in Appendix with the mandrel head and an annular, relative to the first position enlarged contact surface for the sleeve shaft is provided, which projects radially beyond the mandrel head. Retraction movement in this context means a movement with which the mandrel head is moved towards the rivet head. As the rivet mandrel retracts further, the contact surface acts as a riveting punch on the end of the rivet sleeve. In conventional blind rivets, the size of this contact surface is determined and limited by the diameter of the mandrel head. However, the mandrel head diameter is matched to the outside diameter of the sleeve shank or the pre-holes provided in the components and can not be increased arbitrarily. The outer diameter of the ring in the first position is also matched to the outer diameter of the mandrel head and does not project beyond it, or only slightly, eg by a few tenths of a millimeter. Only by turning the ring outward to the second position, the diameter of the ring is increased, so that this projects beyond the mandrel head to the outside.

By turning the ring over a possibility is shown, the contact surface to the sleeve end significantly increased, whereby the formation of a component widely encompassing the closing head is supported and higher joining forces are possible. The formation of a closing head with bead resting against the components is favored when the abutment surface is substantially perpendicular to the longitudinal axis of the mandrel, e.g. in the range of 88 degrees to 92 degrees.

A reliable flipping of the ring is achieved in one embodiment, when the ring has a rhomboid or parallelogram-shaped cross-section and is facing in the first position with a lower edge of the mandrel shaft and facing the sleeve end with an upper edge, wherein the Upper edge is offset radially outwards relative to the lower edge, ie a greater distance from the central longitudinal axis of the rivet mandrel than the lower edge. The forces exerted on the ring when the mandrel is retracted cause a tilting moment on the ring due to the staggered arrangement of the edges, causing it to tilt or flip until the outer surface of the ring adjacent the lower edge abuts the mandrel head arrives. The shape of the ring cross-section is retained by the Umklappvorgang substantially unchanged rhomboid or parallelogram-shaped.

By a variation of the inner angle at the lower edge of the ring can be varied in diamond-shaped or parallelogram-shaped cross section in a simple manner, as far as the folded-over ring over the mandrel head protrudes to the outside. It has proven to be advantageous if the internal angle is formed in a range of 30 to 60 degrees and in particular in a range of 40 to 50 degrees.

A particularly stable positioning of the ring results in one embodiment in that a groove is provided on the circumference in the mandrel shaft, into which the folded-over ring engages in the second position.

The materials for the ring, the inner ring, the rivet mandrel and the sleeve can be selected according to the respective requirements. Advantageously, the ring and rivet dome are made of a high strength metallic material, e.g. a high strength metal or a high strength metal alloy, e.g. made of a high-strength steel. The material strength can e.g. be at least 1000 MPa. In particular, the material of the ring is selected so that the ring can be moved from the first to the second position without cracks occurring in the ring. Advantageously, it is possible to use different materials for the ring and the rivet mandrel and thus further increase the achievable strength of the connection.

The rivet sleeve is preferably made of a metallic material with good flow and forming properties, in particular of a steel with good flow and U mformeigenschaften, such as those used for the rivet sleeves conventional blind rivets. For the inner ring, a metallic material is preferably used, wherein the material is chosen in particular so that the inner ring has a sufficient strength to guide the material of the rivet sleeve away from the mandrel shaft.

The design of the closing head can be favored in an embodiment in which between the ring and the rivet further an inner ring is fitted onto the mandrel shaft, which can be pushed back by the retraction of the rivet mandrel to the ring, wherein one of the rivet sleeve facing top of the inner ring forms a falling from the rivet mandrel on the contact surface sloping. During the riveting operation, the rivet sleeve material is thus directed away from the mandrel shaft to the outside.

In a preferred embodiment, the inner ring has a triangular cross-section and is retractable by retracting the mandrel mandrel between the Nietdorn and the folded-over in the second position ring. In this case, the underside of the inner ring facing the ring preferably comes into full contact with the ring.

Advantageously, the folding over of the ring in one embodiment is facilitated by the fact that the inner ring only comes into contact with the ring with an outer edge as long as the ring is in the first position.

With regard to the rivet connection, the object is achieved by a rivet connection of at least two components, which are connected by means of one or more rivets, wherein a blind rivet as described above is used as the rivet.

The components may be metal components or components made of fiber-reinforced plastics (FRP components). A metal component is in particular a sheet-metal shaped part, for example of an aluminum or steel sheet, which may also be a casting or profile part. A P / K component is preferably a carbon fiber reinforced (CFRP) component, a glass fiber reinforced (GFRP) component or an aramid fiber reinforced component. The FRP component can in particular be a flat, sheet-metal component.

The formation of the rivet connection can be carried out using a conventional riveting pliers in a known manner.

Further advantageous embodiments of the invention will become apparent from the dependent claims.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following description of the embodiments. If the term "can" is used in this application, it is both the technical possibility and the actual technical implementation.

Embodiments will be explained below with reference to the accompanying drawings. Show in it.

FIGS. 1 to 3 show a partial sectional illustration of an exemplary blind rivet in a component arrangement at different points in time of the formation of the riveted connection,

FIG. 1A shows a detailed view Z from FIG. 1,

FIG. 4 shows a perspective view of the blind rivet from FIG. 1,

FIG. 5 shows a perspective view of the blind rivet connection from FIG. 3. FIG. 1 shows an exemplary embodiment of a blind rivet according to the invention. The blind rivet 10 has a rivet sleeve 12 with a sleeve shank 14, a sleeve end 18 and a rivet head 18 radially projecting relative to the sleeve shank 14. The hollow rivet sleeve 12 is penetrated by a rivet mandrel 20 with a mandrel shank 22 which has a predetermined breaking point 24 is provided. On the side facing the end of the housing 16, the rivet pin 20 is widened to form a mandrel head 26. Between the mandrel head 26 and the sleeve end 18, a ring 30 and an inner ring 40 are attached to the mandrel shaft 22. The blind rivet 10 is rotationally symmetrical. Ring 30 and inner ring 40 are configured as ring structures which surround the mandrel shaft 22 in an interruption-free manner. The collar 10 is formed from metallic materials, with high-strength steels preferably being used for the ring 30 and the mandrel 20.

To connect a first component 50 to a second component 60, these are provided with substantially aligned through-holes, e.g. in the form of holes, provided. The blind rivet 10 is removed by means of a riveting tool (not shown), e.g. a rivet pliers with mouthpiece, inserted into the through holes and pressed onto the components. In this case, the rivet head 18, which is also referred to as a setting head, comes into abutment with the first component 50. The blind rivet 10 extends with a part of the sleeve shank 14 through both components 50, 60.

At this time, the ring on the mandrel has a first position, see the detail view in Figure 1A. The ring 30 has a parallelogram-shaped cross-section and rests with its inner surface 32 on the mandrel shaft 22. The ring 30 adjoins with a lower edge 34 to the mandrel head 26 and with an upper edge 36 to the sleeve end 16. The parallelogram-shaped cross-section has at the lower edge 34 an inner angle α of 45 degrees. The outer diameter of the ring 30 corresponds at this time in the We- sentlichen the outer diameter of the sleeve shaft 14 and the mandrel head 26th

FIG. 2 shows the arrangement of FIG. 1 at a time when the rivet mandrel 20 was partially retracted relative to the rivet sleeve 12 by the riveting tool, represented by the arrow P. The retraction movement exerts a compressive force on the lower edge 34 and upper edge 36 of the ring 30. From the radial offset of the edges to each other - the lower edge 34 is located closer to the central longitudinal axis L of the rivet mandrel 20 than the upper edge 36 - results in a moment on the ring 30, which is a folding or flipping the ring 30th to the outside, so that the inner surface 32 moves away from the mandrel shaft 22 and the ring 30 with a previously exposed outer surface 38 (see Figure 1A) to the mandrel head 26 applies. Here, the lower edge 34 of the ring 30 engages in a groove 28 (see Figure 1A), which is adjacent to the mandrel head 26 and circumferentially formed on the mandrel shaft 22. As a result of the folding-over process, the ring 30 is plastically deformed, but the parallelogram-shaped cross section of the ring 30 is retained as far as possible. In this second position, the ring 30 now protrudes in the radial direction beyond the outer edge of the mandrel head 26 and the resulting second outer diameter of the ring 30 is significantly increased compared to the original outer diameter. After folding over, an inner oblique surface, which pointed obliquely inward in the initial state, is now aligned substantially perpendicular to the central longitudinal axis and forms an enlarged abutment surface 39 for the sleeve shank 14.

Upon further retraction of the rivet mandrel 20, the sleeve shank 14 is compressed and bent over to form a closing head 19, and the mandrel 22 ruptures at the predetermined breaking point 24, shown in FIG. 3.

The hollow rivet 10 further has an inner ring 40, which is placed between the ring 30 and rivet sleeve 12 on the rivet mandrel 20, see FIG. 1A, FIG. The inner ring 40 has a triangular cross section, which tapers in a ramp shape on both sides from the rivet mandrel 20 in the radial outward direction to an outer edge 42, wherein the diameter of the inner ring is smaller than the diameter of the ring 30.

When retracting the rivet mandrel, the inner ring 40 is displaced on the mandrel shaft 22. As long as the ring 30 is not folded down, the inner ring 40 contacts the ring 30 only with its outer edge 42. If the ring 30 is folded, the inner ring 40 pushes like a wedge between ring 30 and mandrel shaft 22 and arrives with its ring 30 facing bottom 44 the blanket sleeve 12 zugwandte top 46 of the inner ring 40 forms a mandrel shaft 22 to the contact surface 39 sloping down ramp and forms together with the ring 30 to a deformation of the rivet 12th almost ideal riveting stamp.

FIGS. 4 and 5 show perspective views of the exemplary rivet 10 in a partial section, FIG. 4 showing the arrangement from FIG. 1 before the rivet shank is withdrawn and FIG. 5 shows the finished rivet connection from FIG.

Although the rivet mandrel is shown with a smooth outer contour, it may of course also be structured, e.g. with grooves, grooves, etc. Likewise, more than two components can be connected to each other with the blind rivet.

Due to the enlarged contact surface 39 of the blind rivet invention allows higher joining forces. The flow behavior of the rivet sleeve and the formation of the closing head on the side facing away from the tool can be improved. As a result, higher sustainable loads of the rivet connection in comparison to conventional high-strength blind rivets can be achieved. The embodiments are not to scale and are not restrictive. Modifications in the context of expert action are possible.

LIST OF REFERENCE NUMBERS

10 blind rivet

12 rivet sleeve

14 Hüisenschaft

16 sleeve ends

18 rivet head

19 closing head

20 rivet pin

22 mandrel shaft

24 predetermined breaking point

26 thorn head

28 groove

30 ring

32 inner surface

34 lower edge

36 top edge

38 outer surface

39 contact surface

40 inner ring

42 outer edge 44 underside

46 top

L middle longitudinal axis

P retraction movement

Claims

claims

1. Biindniet (10) with

a rivet sleeve (12) comprising a rivet head (18) for engaging a

Workpiece (50) and a rivet mandrel (20) penetrating the rivet sleeve (12) with a mandrel shaft (22) with mandrel head (26),

characterized _» that

between the rivet lever (12) and the mandrel head (26), a ring (30) is fitted on the mandrel shaft (22), which is formed so that the ring (30) by a retracting movement (P) of the rivet mandrel (20) relative to the rivet ( 12) can be transferred outward from a first position to a second position, wherein a previously exposed outer surface of the ring (30) comes into contact with the mandrel head (26) and an annular contact surface which is enlarged in relation to the first position (39) is provided for the sleeve shaft (14), which projects radially beyond the mandrel head (26).

2. Biindniet according to claim 1,

characterized in that

the ring (30) has a diamond or parallelogram-shaped cross-section, and in the first position with a lower edge (34) facing the mandrel shaft (22) and with an upper edge (38) facing the sleeve end (16) is, wherein the upper edge (36) relative to the lower edge (34) is offset radially outward.

3. Biindniet according to claim 2,

characterized in that

the cross section has an internal angle (a) at the lower edge (34) of the ring (30) in a range of 30 degrees to 60 degrees.

4. Blind rivet according to one of the preceding claims, characterized in that

on the circumferential side in the mandrel shaft (22) has a groove (28) is arranged, in which the ring (30) engages during the transfer.

5. Bündniet according to one of the preceding claims, characterized in that

the ring (30) is formed of a high strength metallic material.

6. Blind rivet according to one of the preceding claims, characterized in that _»

the ring (30) and the rivet mandrel (20) are made of different materials,

7. Blind rivet according to one of the preceding claims, characterized in that

between the ring (30) and the rivet sleeve (12) further an inner ring (40) on the Domschaft (22) is pushed, which is pushed back by retraction of the rivet mandrel (20) to the ring (30), wherein one of the rivet (12) facing the upper side (48) of the inner ring (40) from the Domschaft (22) on the contact surface (39) sloping ramp forms.

8. Blind rivet according to one of the preceding claims, characterized in that

the inner ring (40) has a triangular cross-section and can be inserted by retracting the rivet mandrel (20) in a wedge shape between the rivet mandrel (20) and the ring (30) folded into the second position,

9. Blind rivet according to one of the preceding claims, characterized in that the inner ring (40) comes into contact with the ring (30) only with an outer edge (42) as long as the ring (30) is in the first position.

10. Rivet connection of at least two components, which are connected by means of one or more rivets,

wherein a blind rivet (10) according to one of the preceding patent claims is used as the rivet.