WO2013174612A1

WO2013174612A1 - Friction disc including spines, intended for a motor vehicle clutch

Info

Publication number: WO2013174612A1
Application number: PCT/EP2013/058702
Authority: WO
Inventors: Gérard Crosland; Eric LEJAMTEL; Martine Pagenot
Original assignee: Valeo Materiaux De Friction
Priority date: 2012-05-25
Filing date: 2013-04-26
Publication date: 2013-11-28
Also published as: FR2991015A1; FR2991015B1

Abstract

The present invention relates to a friction disc (400) for a motor vehicle clutch, comprising first (402) and second (404) metal supports maintained secured to one another and coaxial to an axis (406) of the disc by means of a deformable material (409) inserted between the supports; and first (408) and second (410) splines extending tangentially from the first or second support respectively towards a central hole (412), forming pairs of first and second splines, such that each pair of splines includes aligned housings for securing the first and second supports. According to the invention, the splines of one support are associated with positioning surfaces (418) that help to hold a hub (420) in the central hole in a position without insertion of said hub between the pairs of first and second splines.

Description

FRICTION DISC WITH TABS

FOR CLUTCH OF MOTOR VEHICLE

The invention relates to a friction disk for a motor vehicle clutch, in particular of the type comprising a deformable material between two metal supports provided with a lining.

With reference to FIG. 1, a known friction disc 100 for a motor vehicle clutch can be provided with linings 102 and 104 held on respective metal supports 106 or 108.

These metal supports 106 and 108 are parallel and coaxial vis-à-vis a central recess for receiving a hub 1 10 having an input 1 12 for coupling with a transmission shaft. As a result, it is subsequently considered that the support 106 is located on the first face of the disk while the support 108 is located on the second face of the disk.

A layer of deformable material, typically an elastomer or a rubber, is interposed between the two supports 106 and 108. Such a deformable material adheres to the internal faces of the supports 106 and 108, that is to say to the faces of the supports 106 and 108 vis-à-vis.

By way of example, patent applications FR 2,714,432, filed on December 23, 1993, or FR 2,737,267, filed on July 28, 1995, by Valeo SA disclose such friction discs.

In order to arrange and then maintain the hub 1 10 secured to the supports 106 and 108, the latter have tabs 1 14 and 1 16 arranged in pairs such that an ear of the hub 1 10 is inserted between each pair of tongues 1 14 and 1 16, the hub then being secured to the first and second supports 106 and 108 by means of rivets.

The present invention results from the recognition that such an arrangement of the hub to the friction disk is particularly difficult given the accuracy required to simultaneously position the different hub lugs between the pairs of tabs as described below.

In fact, the arrangement of the hub to the disc requires, in a first step shown in FIG. 2, positioning in the recess of the hub 1 10 so that each of its lugs 120 faces the opening located between each pair of tongues to be inserted by pivoting the hub along the axis 122 of the disk (Figure 3).

However, the thickness of a hub lug is about 1.65 mm and the spacing between the tongues of a pair is generally less than 2.5 mm and typically of the order of 2.25 mm. The spacing between the tabs is therefore a value particularly low to allow automation of the positioning of the hub with means having a limited cost. As a result, this operation is performed manually by operators who are confronted with this difficulty of positioning the hub in the recess prior to its final arrangement at the hub.

Moreover, the difficulty of this operation of arranging the hub to the friction disc is increased by the differences in variable spacings between each pair of tongues due to the machining tolerances of these tongues and disc mounting.

Finally, it should be noted that such an arrangement generates a friction disc having a satisfactory mechanical strength when the tongues are mechanically stressed in tension. But this disk resistance may be insufficient when the tongues are stressed in compression, a buckling of these tongues then being risky beyond a certain constraint threshold imposed by their structure.

The present invention aims to solve at least one of these disadvantages. It relates to a friction disk for a motor vehicle clutch comprising a first and a second metal support held solid and coaxial with respect to an axis of the disk by means of a deformable material interposed between said supports, first and second tongues. extending respectively from the first or the second support tangentially to a central recess forming pairs of first and second tongues such that each pair of tongues has aligned housings for securing the first and second supports, characterized in that the tabs of a support are provided with positioning surfaces adapted to participate in maintaining a hub in the central recess in a position without insertion of said hub between said pairs of first and second tabs.

Such a disk has many advantages. In particular, it facilitates the arrangement of a hub friction disk because the positioning of the hub is assisted by the positioning means, that is to say surfaces associated with the tongues. Therefore the operator is guided in the arrangement of the disk hub by these positioning surfaces.

In other words, the hub arrangement operation has a step of assisted positioning during which the hub cooperates with positioning surfaces when it is placed in the recess of the disk, which makes this operation particularly simple and fast.

In one embodiment, the positioning surfaces of the tongues are formed by surfaces attached to the supports and arranged at their tongues. In this case, these reported surfaces can be part of a single piece coaxial with the axis of the disc, for example in the form of a ring or a connecting washer, which allows to use first and second identical supports to reduce manufacturing costs by limiting the number of parts.

In addition, this embodiment generates friction discs with increased mechanical strength by the resistance of the reported surfaces, this resistance can be significant in different types of mechanical stress (traction or compression tabs).

According to one embodiment, the positioning surfaces are formed by lateral surfaces of the second tongues oriented towards the first support but without surfaces of first tongues vis-à-vis.

In one embodiment, the positioning surfaces are formed by extensions of the second tongues devoid of surfaces of first tongues vis-à-vis.

Thus, the hub can be placed in the recess by the face having the first support and come into direct contact with the positioning surfaces, that is to say with lateral surfaces of the second tongues.

In one embodiment, the first and second tongues defining tangential rotations in opposite directions about the axis of the disc, the positioning surfaces of the second tongues are located between their base to the second support and their aligned housing.

According to one embodiment, the first and second tongues defining tangential rotations of identical direction around the axis of the disc, the positioning surfaces of the second tongues are located between the aligned housing and the ends of said second tongues.

In one embodiment, the first support, respectively the second support, is located on the first face, respectively the second face, of the disc.

According to one embodiment, the tabs of at least one support have a symmetry of rotation relative to the axis of the disc.

In one embodiment, the first and second tabs have rotation symmetry with respect to an axis included in the plane of the recess of the disc.

In one embodiment, the second tongues form a peripheral continuous surface, the hub being intended to be placed in abutment against this continuous surface prior to insertion between said continuous surface and the second tongues.

The invention also relates to a method of arranging a hub to a friction disk for a motor vehicle clutch comprising a first and a second metal support held solid and coaxial with respect to a axis of the disc through a deformable material interposed between said supports, first and second tongues extending respectively from the first or the second support tangentially to a central recess forming pairs of first and second tongues such that each pair has aligned housing for securing the first and second supports, characterized in that it comprises at least the step of placing the hub in the central recess and to position it, using positioning surfaces associated with the tongues of at least one support, in a position in contact with said positioning surfaces but without insertion of said hub between pairs of first and second tongues.

In one embodiment, the positioning surfaces associated with the tongues being formed by lateral surfaces of the second tongues oriented towards the first support but without surfaces of first tongues vis-à-vis, it includes the additional step of bringing the hub in contact with these side surfaces and then rotate to insert lugs of the hub between pairs of first and second tongues.

Finally, the subject of the invention is an assembly comprising a friction disc as previously described and a hub mounted on the disc by means of positioning surfaces.

Other advantages of the invention will emerge in the light of the description of an embodiment of the invention made below, by way of illustration and not limitation, with reference to the attached figures in which:

FIGS. 1 to 3, already described, schematically represent a friction disk and its arrangement with a hub according to the prior art,

FIGS. 4 to 9 represent the implementation of a first embodiment of the invention implementing positioning surfaces at the base of the tongues,

FIGS. 10 to 12 illustrate in detail the use of the positioning surfaces according to the first embodiment of the invention,

FIGS. 13 to 15 represent the implementation of a second embodiment of the invention implementing positioning surfaces at the end of the tongues, and

FIGS. 16 and 17 show the implementation of a third embodiment of the invention implementing a continuous positioning surface, FIG. 16 showing an exploded perspective view of a friction disk and its arrangement to a hub. , Figures 17 and 18 showing the method of assembling the hub on such a disc.

In the description below, similar, identical or having equivalent functions can be identified in different figures with the same reference in these different figures.

With reference to FIGS. 4 to 12, there is shown a method of assembling, or arranging, a friction disc 400 for clutching a motor vehicle according to a first embodiment of the invention.

This disc 400 comprises a first support 402 and a second support 404 identical held coaxial with respect to an axis 406 of the disc and secured by means of a deformable elastic material such as a silicone polymer (not shown) interposed between said supports 402 and 404. The elastic deformable material may also be formed by a resilient flat ring of the spring ring type. These supports may be metallic or made of another material, such as plastic.

First tabs 408 and second tongues 410 respectively extend from the first support 402 and the second support 404 tangentially towards a central recess 412 by forming pairs of a first tongue 408 and a second tongue 410 having housings. 418 aligned to secure the first and second supports 402 or 404.

Moreover, this variant uses lateral surfaces 41 1 of the tongues 410 as positioning surfaces, FIG. 8.

More precisely, these lateral surfaces 41 1 of the second tongues 410 are oriented towards the first support 402 of the disc and devoid of surfaces of the first tongues vis-à-vis. These lateral surfaces 41 1 are located between the base and the housings 418 of the tongues 410 of the second support 404 so that they are hereinafter referred to as base surfaces 41 1.

As shown in detail in FIG. 10, these base surfaces 41 1 can receive an ear 430 of the hub 420 resting during its positioning in the recess 412. The tongues are also made in such a way that, when support of the hub on the base surfaces 41 1, they are likely to twist in the opposite direction to the opposite support. Such a twist will also alert a position sensor tabs that the hub is positioned in abutment on the tongue to trigger a signal to allow rotation of the hub through the pairs of tabs. To do this, the tongues are made of spring steel allowing them to be deformed while being able to return to their initial state of departure.

From this position devoid of insertion of the hub 420 between the pairs of tongues (FIGS. 5 and 6), partial pivoting of the hub 420 with respect to the axis 406, facilitated by the support of the lugs 430 of the hub 420 on the base surfaces 41 1, makes it possible to progressively insert the lugs 430 of the hub 420 between the pairs of tabs until housing in the ears of the hub 420 are aligned with the slots 418 of the tabs.

When this alignment is obtained (FIGS. 8 and 11), the base surfaces 41 1 are disengaged and the ears 430 are inserted between the pairs of tongues so that their respective housings (tongues and ear) are aligned. Fastening means (typically rivets 422) then allow to fix these alignments and, more generally, to fix the hub 420 vis-à-vis the supports 402 and 404 (Figures 9 and 12).

In this embodiment, it should also be noted that the first tabs 408 and the second tabs 410 define tangential rotations in opposite directions around the axis 406 of the disc.

Thus, assuming by convention that this direction is defined by considering the disc 400 from the same face (for example first face), it appears that the tabs 408 of the first support 402 define a clockwise rotation (with reference to the movement of the needles). a watch) while the tongues 410 of the second support 404 define a counter-clockwise rotation.

Such a difference in the arrangement of the tongues makes it possible to reinforce the resistance of the friction disc in the cases where the disc is biased in "retro" mode, that is to say when the first tongues of the first support are stressed in compression.

In fact, in this case, the tongues 410 of the second support 404 are biased in tension, which limits the risk of buckling of the first tongues 408 which are strongly assisted by the second tongues 410.

In a second variant of the invention, described with reference to FIGS. 13 to 15, the first tongues 408 and the second tongues 610 of the first and second supports 402 and 604 define tangential rotations of identical direction (clockwise) around the 406 axis of the disk, which increases the strength of the disk in traction

Referring to Figure 13 is described the step of arranging the first metal support 402 and the second metal support 604 with respective gaskets 403 and 405 and with a deformable material 409.

It should be noted that, if the tabs 408 and 610 extend similarly from their supports 402 and 604 tangentially to a central recess, the second tabs 610 have an elongate end 612 (FIGS. 14 and 15) which allows to provide a bearing surface to a hub coming into contact with these surfaces in the central recess.

Thus, these extensions 612 form positioning surfaces capable of participating in maintaining a hub placed in the recess in one position. assembly without insertion of said hub between pairs of first and second tongues.

In fact, a hub inserted in the central recess comes into contact with these ends 612 even before being inserted, subsequently, between pairs of tongues.

In fact, the present invention is capable of many variants. For example, the supports described in the embodiments have symmetries. In particular, the tongues of the same support have between them a rotational symmetry with respect to the axis of the disk in the set of embodiments. Such an arrangement is advantageous for reasons of mechanical strength and manufacturing cost.

Likewise a symmetry with respect to the plane of the disk (eg FIG. 4) or of rotation with respect to an axis comprised in the plane of the disk (eg FIG. 5) can also be used between the various supports, but variants devoid of such symmetries can be considered in the context of the invention.

It should be noted that each support may also include an odd number of tabs.

Depending on the variants, the arrangement of the hub to the disk can be done by placing the hub in the recess of the disk by the first face or by the second face of the disk. Or the positioning means are associated with the tongues of the support located on the opposite face so that, if the hub is approached by the first face (respectively the first face), the positioning means are associated with the tongues of the second face ( respectively of the input face).

The shape of the tabs must be complementary to the shape of the ears of the hub.

In the case where the tabs are superimposed with one end protruding, the insertion of the hub can be done only on one side, that is to say on the opposite side where the tabs have positioning surfaces.

In the case where the tabs are crossed, the insertion of the hub can be done by both sides of the disc.

Figures 16 to 18 illustrate a fourth embodiment of the invention. In this embodiment, the second tabs merge to form a single continuous and peripheral surface 710. Thus, during assembly, the hub 420 is placed between two first tongues 408 so that the surfaces of the lugs of the hub 420 are positioned in abutment against the single surface 710, FIG. 18. Then, the hub 420 is rotated. so that his ears are inserted between the single surface 710 and the first tabs 408 until the lug holes of the hub 420 align with the orifices of the first tabs 408 and the single surface 710, FIG. 19.

Claims

1. Friction disc (400) for a motor vehicle clutch comprising a first (402) and a second (404, 604) metal support secured and coaxial with respect to an axis (406) of the disc (400) via a deformable material (409) interposed between said supports (402, 404, 604), first (408) and second (410, 610) tabs respectively extending from the first (402) or second (404, 604) support tangentially to a central recess (412) forming pairs of a first (408) and a second (410, 610) tabs such that each pair of tabs has recesses (418) aligned to engage the first ( 402) and second (404, 604) supports, characterized in that the tongues (408, 410, 610, 710) of a support (402, 404, 604) are provided with positioning surfaces (41 1, 612) able to participate maintaining a hub (420) in the central recess (412) at a position without insertion of the said hub (420) between said pairs of first (408) and second (410, 610, 710) tabs.

2. Disk (400) according to claim 1, characterized in that the positioning surfaces (41 1, 612) are formed by lateral surfaces of the second tongues (410, 610, 710) oriented towards the first support (402) and devoid of surfaces of first tabs (408) vis-à-vis.

3. Disc (400) according to claim 2, characterized in that the first and second tongues (408, 410) defining tangential rotations in opposite directions about the axis (406) of the disc (400), the surfaces positioning (41 1) of the second tabs (410) are located between their bases to the second support (404) and their housings aligned in the pairs of tabs.

4. Disc (400) according to claim 3, characterized in that the first and second tongues (408, 610) defining tangential rotations of identical direction around the axis (406) of the disc (400), the surfaces positioning (612) second tabs (410) are located between the aligned housing and the ends of said second tongues (410).

5. Disc (400) according to one of claims 1 to 4 characterized in that the first support (402), respectively the second support (404), is located on the first face, respectively the second face, of the disc (400 ).

6. Disc (400) according to one of the preceding claims, characterized in that the tabs (408, 410) of at least one support (402, 404) have a symmetry of rotation relative to the axis (406) of the disc.

7. Disk (400) according to one of the preceding claims, characterized in that the first (408) and the second (410) tabs have a symmetry of rotation relative to an axis included in the plane of the disk (400).

8. Disc (400) according to claim 1, characterized in that the second tongues form a peripheral continuous surface (710), the hub being intended to be placed in abutment against this continuous surface prior to insertion between said continuous surface and the second tongues.

9. A method of arranging a hub (420) to a motor vehicle clutch disc (400) comprising a first (402) and a second (404, 604) metal support held coaxial with respect to an axis ( 406) of the disc and secured by means of a deformable material (409) interposed between said supports (402, 404, 604), first (408) and second (410, 610, 710) tongues respectively extending from the first (408) and 402) or the second (404, 604) support tangentially to a central recess (412) forming pairs of first (408) and second (410, 610) tabs such that each pair has housings aligned to secure the first (402) and second (404, 604) supports, characterized in that it comprises at least the step of placing the hub (420) in the central recess (412) and to position it, to using positioning surfaces (41 1, 612) associated with the tongues (408, 410, 610, 710) of at least a support (402, 404, 604) at a position in contact with said positioning surfaces (418, 41 1, 612) but without insertion of said hub (420) between pairs of first (408) and second (410, 610,710) tabs.

Arrangement according to claim 13, characterized in that the positioning surfaces (41 1, 612) associated with the tongues (610, 710) are formed by side surfaces of the second tongues (610, 710) facing the first support but without surfaces of first tabs (408) facing each other, it comprises the additional step of bringing the hub (420) into contact with these lateral surfaces (41 1, 612) and then rotating it in order to inserting lugs (620) from the hub (420) between pairs of first (408) and second (610,710) tabs.

1 1. An assembly comprising a friction disc according to one of claims 1 to 10 and a hub mounted on the disc with positioning surfaces (41 1,