WO2009030480A2

WO2009030480A2 - Fastener

Info

Publication number: WO2009030480A2
Application number: PCT/EP2008/007242
Authority: WO
Inventors: Michael Stumpf
Original assignee: Bölhoff Verbindungstechnik Gmbh
Priority date: 2007-09-04
Filing date: 2008-09-04
Publication date: 2009-03-12
Also published as: WO2009030480A3; DE102007041949B3

Abstract

The present invention relates to a fastener (1) having a damping function for connecting a first (10) and a second component (20) and to a method for the production thereof. The fastener (1) is characterized by the following characteristics: a screw (30) having a screw barrel (32), a screw head (36) and a thread region (34), on which a disk (40) is captively arranged, a support sleeve (50) that can support the fastener (1) on the second component (20), and a damping sleeve (60), in which the support sleeve (50) is housed and which comprises a collar (62) extending beyond the support sleeve (50), the disk (40) being attached to said collar.

Description

fasteners

1. Field of the invention

The present invention relates to a fastener with damping function for connecting a first and a second component and a method for its production.

2. Background of the invention

Various constructions for fasteners with supporting and damping function are known in the prior art. These are described, for example, in EP 1 231 390 B1, DE 195 10 349 C2, DE 199 24 502 C2 and EP 1 245 842 B1.

EP 1 231 390 B1 describes a screw with screw head, screw shank and threaded area on which a support sleeve is arranged. This support sleeve is supported directly on the screw head, so that vibrations between the component and the screw are transmitted undamped. In order to fix the support sleeve captive on the screw shaft, an impression is introduced whose inner diameter is smaller than the outer diameter of the threaded portion.

In EP 1 245 842 B1, the support sleeve is fastened to the screw shank via a damping element. The damping element passes through openings in the support sleeve and thereby narrows the inner diameter of the support sleeve. In the case of wear of the damper element projecting in the direction of the screw shank, however, the captive properties of the support sleeve are no longer guaranteed, which leads to disadvantages. DE 195 10 349 C2 and DE 199 24 502 C2 describe fasteners which have a disk as a captive. The disc is located between the screw head and threaded portion due to their smaller inner diameter compared to the outer diameter of the threaded portion. In addition, the disc is connected to the support sleeve via an elastomeric element, so that the support sleeve is also held captive on the screw. The elastomeric element extends close to the disk to be fastened, so that it has only a limited damping and allows tilting of the support sleeve in a component opening. In addition, vibrations of a fastened component can be transmitted directly to the support sleeve.

Based on the above-described disadvantages of the prior art, it is the object of the present invention to provide an improved damper function fastener for joining first and second components in comparison with the prior art. ,

3. Summary of the invention

The above object is achieved by a fastener according to independent claim 1 and by a method for its production according to independent claim 9.

The fastener with damping function for connecting a first and a second component has the following features: a screw whose screw shaft between the screw head and threaded portion has a smaller diameter than the threaded portion, so that a disc is captively fastened to the screw, a support sleeve, with the fastener on the second component can be supported, and a damping sleeve, in which the support sleeve is received and which comprises a projecting beyond the support sleeve collar to which the disc is attached.

By means of the construction described above, a fastener is provided as a cohesive unit of screw, washer, support sleeve and damping sleeve. This allows a simplified insertion of the fastener in a few steps. In addition, the individual components of the fastener are reliable interconnected so that they provide adequate support and damping functions despite effective installation.

According to one embodiment of the present invention, the collar of the damping sleeve comprises a snap connection, in which the disc can be latched and thus fastened. This snap connection is realized, for example, with the aid of an undercut disposed within the collar, which extends circumferentially on the inside of the collar. According to other alternatives, it is also conceivable to attach the disc in other ways to the support sleeve.

In order to support a permanent positioning of the fastener in the first component, the damping sleeve has an anchoring profiling on its outer side. Similarly, it is preferable to provide the support sleeve on its outer side with a holding profile, which supports holding the support sleeve within the damping sleeve. To reduce the weight of the support sleeve, at least two regions of different inner diameters are preferably provided. In this way, one bears, for example, the weight requirements in the automotive industry bill, which should lead to a reduction in fuel consumption.

To produce the fastener described above, the following steps are used: providing a screw with screw shank and threaded portion to which a disc is captively mounted, inserting a support sleeve in a damping sleeve or sheathing the support sleeve with plastic or a rubber material, which forms the damping sleeve, said Each of the damping sleeve comprises a collar for fastening the disk, and fastening the disk in the collar of the damping sleeve, so that the fastener is formed as a coherent unit of screw, washer, support sleeve and damping sleeve.

4. Brief description of the accompanying figures

Preferred embodiments of the present invention are described in the accompanying drawings

Figures shown. Show it: 1 is a sectional view of a preferred embodiment of the fastener in the installed state,

2 is a perspective sectional view according to the embodiment of Fig. 1,

3 is an exploded view of the embodiment of FIG. 1,

4A is a perspective view of a preferred embodiment of the damping sleeve,

4B is a sectional view of the damping sleeve according to FIG. 4A,

5A is a perspective view of a preferred embodiment of the support sleeve,

5B is a sectional view of the support sleeve of FIG. 5A,

6 is a sectional view of a preferred embodiment of the damping sleeve with support sleeve,

Fig. 7 is a perspective view of a preferred embodiment of the screw with disc and the first component and

Fig. 8 is a flowchart illustrating a preferred embodiment of the manufacturing method of the fastener.

5. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention provides a fastener 1 and a method of making the same, for example by attaching housing parts or panels to automobiles. The fastener 1 is provided as a contiguous unit, whereby a simplified assembly of first 10 and second component 20 is achieved. In addition, the fastener 1 realizes a support function via the later-described support sleeve 50 and a damping function via a damping sleeve 60 surrounding the support sleeve 50.

A preferred embodiment of the fastener 1 is shown in FIG. 1 as a sectional view, in FIG. 2 as a perspective sectional view and in FIG. 3 as an exploded view. The fastener 1 connects the first component 10, for example a plastic panel, to the second component 20, for example a bearing part of a vehicle body. For this purpose, a bore 22 is provided with thread in the second component 20. The bore 22 and the thread mounted therein The screw 30 also includes a screw head 36 and a screw shank 32. The screw head 36 is provided with a standard force engaging feature such as a hexagonal head or a cross or slot structure The cylindrical portion of the screw shaft 32 serves to receive a preferably hardened disc 40 (see below). At the screw shaft 32, the threaded portion 34 connects. In order to assist the threading of the screw 30 in the bore 22 of the second component, the screw head 36 facing away from the end of the threaded portion 34 is preferably equipped with a chamfered cylindrical portion 38 as Einfädelhilfe.

The screw 30 is made of a standard material. For attachment of the disc 40 on the screw shaft 32, the disc 40 is first threaded, for example, on a screw blank without threaded portion. Subsequently, the threaded portion 34 is produced by rolling. This results in that the outer diameter of the threaded portion 34 is greater than the inner diameter of the disc 40 and the outer diameter of the screw shaft 32. In this way, the disc 40 is captively connected to the screw 30. The fastener 1 also includes a support sleeve 50 which is surrounded by a damping sleeve 60. Within the support sleeve 50, the screw 30 is arranged. In the installed state of the fastener 1 support sleeve 50 and damping sleeve 60 are received in a through hole 12 of the first component 10.

The support sleeve 50 is shown according to a preferred embodiment in Figures 5A, B. It serves as a pressure or force limiter with regard to the first component 10. By supporting the support sleeve 50 on the second component 20, a mechanical overload of the first component 20 is prevented. In this way, clamping forces on the first component 10 and screw 30 are avoided, which would result in a relaxation of the plastic in the region of the through-hole 12 in the case of a first component 10 made of plastic. Due to the relaxation tolerances would arise, which would cause a loosening or rattling of the first component 10 on the screw 30. The support sleeve 50 thus absorbs most of the force flow between the screw 30 and the second component 20. For the above reasons, the support sleeve 50 is made of a durable material that resists buckling and ensures sufficient stability for the fastener 1. A preferred embodiment is to produce the support sleeve 50 made of steel, for example as a cold impact element. In order to reduce the weight of the support sleeve 50, two areas 54, 56 of different inner diameters are preferably provided. Despite the increased inner diameter in the region 56, the region 54 provides sufficient guidance of the screw 30 within the support sleeve 50. In addition, the through hole 58 in the support sleeve 50 according to an alternative to DIN EN 20273 executed.

The support sleeve 50 is also to be dimensioned so that a buckling or buckling of the support sleeve 50 is avoided. In this way unwanted radial stresses are kept away from the surrounding material. The position of the region 54 with a smaller passage cross-section and the region 56 with a larger passage cross-section is based on the permissible surface pressures of the partners to be connected. The aim is to avoid marks on the support sleeve 50. Therefore, the region 56 is disposed on the side of the preferably hardened disc 40. The region 56 is preferably applied to low strength components, such as. B Engine blocks, body parts, oil sumps made of light metals or of plastic components.

On its outer side, the support sleeve 50 according to the embodiment shown in Fig. 5A on a retaining profiling 52. The retaining profile 52 supports the support of the support sleeve 50 within the damping sleeve 60, which is described in more detail below. The retaining profiling 52 consists, for example, of the illustrated longitudinal edge, which according to one embodiment is designed according to DIN 82RAA 0.6. It is also another form of a retaining profiling 52 conceivable that acts as a rotational security and / or prevents loosening of the support sleeve 50 from the damping sleeve 60.

Furthermore, the axial end faces of the support sleeve 50 are formed as contact surfaces, which are supported on the second component 20 and the disc 40. In this context, it is conceivable to use the contact surfaces flat, with a shoulder or in other Form rer design to optimally ensure the support of the support sleeve 50.

As shown in Figures 1, 2 and 6, the damping sleeve 60 surrounds the support sleeve 50. The damping sleeve 60 is made of a damping material that can compensate for mechanical component vibrations. Preferred materials are rubber materials or generally plastics, such as thermoplastic elastomers, which are suitably processed by vulcanization or by spraying. The support sleeve 50 is sheathed with the damping sleeve 60 or the support sleeve 50 is pressed or glued into the damping sleeve 60 or secured therein in any other suitable manner. In this manner, the damping sleeve 60 preferably completely surrounds the support sleeve 50. Within this arrangement, axial displacement of the support sleeve 50 and the damping sleeve 60 with respect to each other is prevented by the retaining profile 52 (see above).

The damping sleeve 60 is shown in more detail in Figures 4A, B. In addition to a passage opening 68, the damping sleeve 60 comprises an anchoring profiling 66 on its outside. According to a preferred embodiment, the anchoring profiling 66 is realized in the form of cams 66 extending in the axial direction. The anchoring profiling 66 may generally have any shape that supports elastic anchoring of the damping sleeve 60 and thus of the fastener 1 in the through hole 12 of the first component 10. Thus, circumferential rings on the outside of the damping sleeve 60 as anchoring profiling 66 are suitable.

As a further alternative, a fit of the damping sleeve 60 is conceivable, so that the damping sleeve 60 is held sufficiently without anchoring profiling 66 in the passage 12.

At its end facing the second component 20, the damping sleeve 60 preferably comprises a chamfer on the element edge, which facilitates the mounting of the fastener 1. The screw head 36 facing the end of the damping sleeve 60 has a collar 62. The collar 62 is preferably cylindrical and has a larger inner diameter than the outer diameter of the disc 40 and the remaining inner diameter of the damping sleeve 60. Within the collar 62, the disc 40 is received and held. The hold of the disc 40 in the collar 62 is sufficiently large so that the screw 30 can not fall out of the fastener 1 by its own weight. It is further preferred to adjust the grip of the disc 40 in the collar 62 such that minimum extension forces of the disc 40 from the collar 62 in the range of 50 to 70 N are required. By holding the disc 40 and thus also the screw 30 in the collar 62 and thus in the damping sleeve 60 with support sleeve 50, the fastener 1 is provided as a coherent unit.

According to a preferred embodiment, the disc 40 is held by an undercut 64 on the collar 62. To accomplish this, the disk 40 is pressed into the collar 62 and snaps behind the undercut 64. The undercut 64 is, for example, fully formed as a lip or in the form of individual detents (not shown) on the inside of the collar 62.

It is also conceivable that the collar 62 has no protruding edge with undercut 64. Instead, at least one axial projection extends from the collar 62, which engages in a corresponding opening within the disc 40 and locked there. Another alternative is to gluing or gluing the disc 40 on or in the collar 62. In order to ensure this functionality, all connections between the damping sleeve 60 and the disc 40 are therefore conceivable which make it possible to provide the fastener 1 as a unit.

If the collar 62 is formed with an undercut 64 according to FIG. 6, this provides a detachable connection between the disk 40 and the damping sleeve 60. In this construction, a broken screw 30 could be replaced and the new screw with disc in the damping sleeve 60 are locked.

It is further preferred, the fastener 1 with damping function for fixing a thin-walled first component 10, for example, an attachment 10 with a Component thickness of 1 to 4 mm, to use. Such components 10 include sheets and attachments of non-reinforced or reinforced plastic, such as CFRP and SMC, to name just a few alternatives. For this application, the fastener 1 is used with adapted dimensions and alternative shape compared to the embodiments described above.

According to a first embodiment, the length of damping sleeve 60 and support sleeve 50 is reduced and thereby adapted to the thickness of the component 10. The anchoring profiling 66 on the radially outer side of the damping sleeve 60 is more pronounced in comparison to the above embodiments in order to hold the thin-walled component 10 between anchoring profiling 66 and collar 62. In addition, the anchoring profiling 66 extends to the end of the damping sleeve 60, which faces away from the collar 62, and is supported on the second component 20.

For holding the component 10, the radial outward extension of the anchoring profiling 66 is increased and / or the number of circumferentially disposed profiled webs 66 is increased. According to a further alternative of the fastener 1, the anchoring profiling 66 is formed peripherally circumferentially, while its outer diameter and / or its axial extent is smaller, equal to or greater than the outer diameter and / or the axial extent of the collar 62 is (are). Based on this shaping of the outer profiling 66, the first component 10 is held in a form-fitting manner between collar 62 and outer profiling 66.

Furthermore, the side facing away from the first component 10 of the outer profiling 66 is supported on the second component 20. If the outer profiling 66 plate-like, it is similar to a flange or collar on the second component 20 and forms the mounting surface of the support sleeve 60. In order to adjust the damping properties of the damping sleeve 60 and improve the plate-like outer profile 66 in the area of the mounting surface as a solid material or formed with lamellae.

The outer diameter of the outer profile 66 is selected as a function of the SHORE hardnesses of the elastomer of the damping sleeve 60 used. Furthermore, outer diameters of the outer profile 66 and / or SHORE Hardness of the elastomer used of the damping sleeve 60 set such that the first component 10 with the desired effort of the damping sleeve 60 is removable, ie required Ausknöpfkräfte be achieved.

For the manufacture of the fastener 1, reference is made to the flowchart in FIG. 8. First, in step A, the screw 30 is manufactured with the washer 40 captively attached thereto. This is exemplified above. Subsequently, in step B, the support sleeve 50 is inserted into the damping sleeve 60 or pressed or glued. According to an alternative to step B, the support sleeve 50 is encased in plastic or a rubber material in step C. The sheathing can be realized on the one hand by injection molding of a thermoplastic elastomer or on the other hand by vulcanization with a rubber material. Subsequently, in step D, the disc 40 is fixed in or on the collar 62. As has already been described above, the fastening takes place by means of snapping, gluing or the like.

According to a preferred addition to the manufacturing process, the support sleeve 50 is made with at least two portions 54, 56 of different inner diameters to reduce the weight of the support sleeve in this way.

Claims

claims

A damper function fastener (1) for connecting a first (10) and a second component (20) having the following features:

a. a screw (30), the screw shaft (32) between the screw head (36) and threaded portion (34) has a smaller diameter than the threaded portion (34), so that a disc (40) is captively fixed to the screw (30),

b. a support sleeve (50), with which the fastener (1) on the second component (20) can be supported, and

c. a damping sleeve (60) in which the support sleeve (50) is accommodated and which comprises a collar (62) projecting beyond the support sleeve (50) and to which the disc (40) is fastened.

2. fastener (1) according to claim 1, the support sleeve (50) is completely received in the damping sleeve (60).

3. fastener (1) according to claim 1 or 2, the collar (62) has a snap connection (64) in which the disc (40) can be latched.

4. fastener (1) according to one of the preceding claims, whose collar (62) has a larger inner diameter than the rest of the damping sleeve (40), so that the disc (40) between an undercut (64) in the collar (62) and the rest Damping sleeve (60) is durable.

5. fastener (1) according to any one of the preceding claims, the damping sleeve (60) on the outside of an anchoring profiling (66), which supports a holding of the fastener (1) in the first component (10).

6. fastener (1) according to one of the preceding claims, the damping sleeve (60) on the outside at the collar (62) opposite end a chamfer (68), which assists insertion of the fastener (1) in the first component (10).

7. fastener (1) according to one of the preceding claims, the support sleeve (50) on the outside of a retaining profiling (52) which supports holding the support sleeve (50) within the damping sleeve (60).

8. fastener (1) according to one of the preceding claims, the support sleeve (50) has at least two regions (54, 56) of different inner diameter, with which a weight reduction of the support sleeve (50) is adjustable.

A manufacturing method of a damper-type fastener (1), comprising the steps of:

a. Providing (A) a screw (30) with screw shank (32) and threaded area (34) to which a disc (40) is captively fastened,

b. Inserting (B) a support sleeve (50) in a damping sleeve (60) or sheathing (C) of the support sleeve (50) with plastic or a rubber material forming the damping sleeve (60), wherein the damping sleeve (60) each have a collar (62 ) for fastening the disk (40) and

c. Attaching (D) the washer (40) in the collar (62) of the damping sleeve (60) so that the fastener (1) is a coherent unit of screw (30), washer (40), support sleeve (50) and damping sleeve (60 ) is formed.

10. The manufacturing method according to claim 9, wherein the disc (40) by snapping (D) at an undercut (64) in the collar (62) of the damping sleeve (60) is attached.

11. A manufacturing method according to claim 9 or 10, further comprising the step. Producing the support sleeve (50) with at least two regions (54, 56) of different inner diameter, in particular as a cold impact element.