FR2688039A1 - Clutch release bearing mounting, particularly for motor vehicle - Google Patents

Abstract

The clutch release bearing mounting includes a clutch release bearing (1) provided with an operating element (23) with a tip (24), a coupling member (16) carried by a closing-up component (13) and elastic holding means (4) for permanently jamming the coupling member (16) between a drive bearing surface (18) of the closing-up component and an action flank (3) of a groove (2) of the tip (24). The groove (2) of the tip (24) is extended on the opposite side from the action flank (3) for fitting at least one elastic washer (5, 6-51, 52-50, 60) with axial action, in advance. Application: motor vehicles.

Description

 The present invention relates generally to a clutch release bearing assembly, in particular for a motor vehicle, of the type comprising a clutch release bearing provided with an attack element with a nose, adapted to act in traction on the internal face d 'A clutch disengaging device, such as a diaphragm, by means of a docking piece preassembled on said disengaging device, a radially elastically deformable coupling member, carried internally by the docking piece, for fastening in traction of the docking piece to the attack element and elastic holding means acting axially between the attack element and the docking piece to permanently wedge the coupling member between a bearing surface d drive, which has the internal bore of a sleeve belonging to the docking part, and a flank of action of a groove belonging to the nose of the attack element penetrating inside r of the socket of the docking part.

 Such an assembly avoids any uncoupling of the stop with the docking part and reduces wear at the level of the coupling member. This assembly is described in document FR-A-2 544 035. In this document, a wavy retaining spring is incorporated into a pre-assembled subassembly of the docking part with the declutching device.

 When said subassembly engages radially outside the attack element, this arrangement requires modifying the docking part.

 Indeed this leads either to modify the socket of the docking part so that it has axial tabs provided with a groove for hooking the retaining spring, or to notch even more the support flange of the part d 'docking for mounting of axial lugs provided for this purpose from place to place around the periphery of the retaining spring.

 This latter arrangement is particularly disadvantageous since it leads to weakening the docking part.

 In addition, the retaining spring cannot have a radial extent as large as desired.

 The object of the present invention is to overcome these drawbacks and therefore to create, in a simple and economical manner, a new clutch release bearing assembly with elastic holding means, without increasing the size of the docking part and without modifying in a manner deep this one.

 According to the invention, a stop of the above-mentioned type is characterized in that the groove of the nose of the attack element is extended on the side opposite to the action flank, for mounting in advance of at least one elastic action washer. axial constituting the elastic holding means.

 Thanks to the invention, the elastic washer is incorporated into the attack element, the sides of the groove constituting natural stops for maintaining said washer on the declutching stop.

 The action flank thus has an additional function of retaining the elastic washer. In addition, the docking part is generally unchanged, the length of its socket possibly being reduced.

 In addition, the resistance of the docking piece is preserved and the elastic washer can have a radial extent as large as desired, in particular for good precision of the holding tightening.

 Thus according to one characteristic, the external diameter of the elastic washer is greater than the external diameter of the free end of the sleeve.

Thanks to this, it is certain that during assembly the sleeve will come into contact with the elastic washer, which thus offers a large range to said sleeve.

 It will be appreciated that the arrangement according to the invention is also economical at the level of the attack element because this leads to lengthening the throat of the latter without increasing the length of the nose.

 This application is of universal use, the docking part can be pre-assembled in any way on the clutch disengaging device.

In addition, in the case where the coupling member consists of a rod with strands hooked one on the other, as described in the document
FR-A-2 630 174, the elastic washer according to the invention can easily be housed in the free space delimited by said strands, while having a large radial size.

 In all cases, it is certain that a decoupling of the stopper with the docking part is avoided, even in the event of a temporary cancellation or not of the preload permanently requesting, usually, for example using a spring acting on the declutching fork, the stop in the direction opposite to the declutching device. The same applies in the event of nutation or "swiveling" movement of the docking part relative to the clutch release bearing.

 Of course, according to another characteristic, it is possible to mount in advance in the extended groove at least two elastic washers with axial action constituting the elastic holding means, said elastic washers being mounted in series and acting between the free end of the socket of the docking part and the other side of the groove.

 This arrangement solves an additional problem. In fact, in the case of a single elastic washer, as in document FR-A-2 544 035, the clipping stroke is not negligible and, for secure mounting, by simply snapping on the declutching stop, it is necessary overtravel and compress the elastic retaining member even more. There is therefore a risk of damaging the elastic retaining member, by over-stressing it, its elastic limit possibly being exceeded.

 To overcome this drawback, one can consider using an arrangement with elastic means, in the form of two elastic washers mounted in series.

 Such a series mounting of springs makes it possible to combine their deflection for an identical force. This assembly allows an easy snap-fitting of the stop with an overtravel but is impossible with a construction of the type of that of document FR-A-2 544 035. It is then necessary to install the elastic washers at the external periphery of the docking part as described in document FR-A-2 629 882.

 This arrangement is also not entirely satisfactory, since it leads, on the one hand, to modifying and lengthening the docking part at its outer periphery, for mounting elastic washers and, on the other hand, to slidingly mount a support piece on the attack element, said piece bearing on a circlip carried by the attack element. The number of pieces is therefore increased.

 Thanks to the aforementioned characteristic with a minimum of parts, without changing the docking part, there is a series mounting of elastic washers making it possible to easily carry out, with sufficient overtravel, mounting by clipping (or snap) of long stroke, with a precise force, of the stop on the whole of the docking part - coupling member, without risk of damaging said washers.

 According to another characteristic, the or each elastic washer has at its internal periphery holding means, such as legs inclined in the direction of the side of action, for holding the or said washers in the groove. These means allow centering of the elastic washer (s) and make them captive. In addition, in the case of inclined legs, the mounting of the washer (s) on the nose is easy, without having to respect precise manufacturing tolerances.

 Indeed, this mounting can be done by simple axial threading with retraction of the tabs until they penetrate tightly into the groove. These inclined legs also allow a refocusing of the washers in operation.

 Advantageously, the inclination of said legs is generally equal to the inclination of the engagement surface, which has the socket of the docking part at its free end.

 Thanks to this arrangement, snap-on mounting is easy because mutual centering of the docking piece with the elastic washer concerned is carried out during mounting. In addition, the elastic washer does not risk tipping.

 Advantageously, the other flank of the groove has externally a transverse portion connecting to a generally inclined internal portion matching the shape of the washer or washers.

 Thanks to this arrangement, a stop is formed for the elastic retaining washer (s) and the resistance of the leading nose is increased, said internal portion being adapted to the shape of the inclined legs of the elastic retaining washer (s).

 These elastic holding means can consist of two corrugated elastic washers mounted head to tail against each other. In this case, indexing means, also forming anti-rotation means, are provided for indexing and preventing any rotation between said washers.

 Indeed, the two washers can be identical to each other, for this it suffices to offset angularly one washer with respect to the other, so that the hollow of one of the washers comes into contact with the top of the other washer. Thanks to the aforementioned indexing means, these washers will be held in place, which guarantees their mounting in series. Otherwise, the washers would overlap one another and no longer act in series.

 These indexing means can consist of a joining by gluing or welding of said washers with each other at their contact zone. Alternatively, the indexing means may consist of a screen washer interposed between said wavy washers and guaranteeing the series mounting of said washers.

 As a variant, it is possible to provide tabs which are nested one inside the other at the level of the nodes or contact zones of said washers. Thanks to the invention, it is also possible to use Belleville washers with internal retaining and centering tabs, said washers having an inclination in the opposite direction.

The following description illustrates the invention with reference to the accompanying drawings in which
- Figure 1 is an axial sectional view in its upper part of a clutch release bearing assembly according to the invention, and in its lower part an axial view of the clutch release bearing without the docking part;
- Figure 2 is a half-sectional view of the clutch release bearing without its sleeve and its front cover snap-fastening of the stop
- Figure 3 is a sectional view of the stopper of Figure 2 when it clicks into place with the docking part, the coupling member being shown in various positions
- Figure 4 is a simplified view in elongation of the mounting of the elastic retaining washers according to Figures 1 to 3;
- Figure 5 is a view similar to Figure 4 for another alternative embodiment;
- Figure 6 is a partial view of the nose of the clutch release bearing before it snaps for another variant of the elastic retaining washers;
- Figures 7A and 7B are simplified views of the mounting of the elastic retaining washers of Figure 6 at their node respectively before and after mounting;
- Figure 8 is a half-view in axial section of a clutch release bearing assembly for yet another embodiment;
- Figures 9 and 10 are views similar to Figure 2 for yet other alternative embodiments.

 As illustrated in the figures, this involves coupling a clutch release bearing 1 to the clutch release device 11 of a clutch formed here by the fingers of a centrally open diaphragm 10. The stop acts in traction on the declutching device 11 to disengage the clutch.

 To do this, for coupling the stopper 1 to this declutching device 11, it is attached to the end of the latter a docking piece 13, of annular shape, here in stamped sheet metal.

 The part 13, also called the support cup, comprises, on the one hand, on the side of the internal face of the declutching device 11 opposite the stop 10, radially a flange 14 for action on the internal face of the device 11 and, d on the other hand, axially a central sleeve 15 integrally with the flange 14 and carrying a coupling member 16, which extends annularly inside said sleeve 15.

 The member 16 is elastically deformable radially and is suitable for coupling the declutching stopper 1 by simple snap-fastening thereof, at least in the axial direction going from the flange 14 to the member 16 (in the declutching direction by traction). This coupling is carried out, in a manner known per se, by relative approximation of a primary block, integral with the engine of the motor vehicle and comprising the clutch with the docking part - coupling member assembly, and a block secondary comprising the gearbox with the clutch release bearing carried by it.

 More precisely here the flange 14 is curved for local support on the internal end of the fingers 11, while the sleeve 15, of axial orientation, passes through the central opening of the diaphragm 10 and has, on the one hand, at its end free, on the side of the stop 1, a frustoconical bearing 17 for engagement on the stop and, on the other hand, a shoulder 18 formed thanks to a change in diameter of the bore of the bush 15.

 The member 16, established radially between the stop 10 and the part 13 while being carried internally by said part 13, is here an elastic rod with circular transverse outline opened by two strands 19, which each pass through the sleeve 15 in favor of a recess 20 and form radially beyond this socket 15 gripping means.

Alternatively, as in the document
FR-A-2 629 882, it may be a simple rod, or a split elastic ring, preferably chamfered, mounted in a groove in the sleeve 15.

 The rod 16, for its retention relative to the sleeve 15, also has, in cooperation with the strands 19, two radial tabs, which are each engaged with a recess as in document FR-A-2 630 174.

Thus the strands are hooked elastically one on the other, so that the rod 16 is closed circumferentially on itself under stress.

 To release the stop, it suffices to unhook the two strands 19.

The part 13 is premounted on the declutching device 10. To do this, retaining means 21 are suitable for ensuring, in cooperation with the flange 14, the maintenance of the docking part 13 on the fingers 11. Here these means consist in retaining tabs 21 coming from the external periphery of the collar 14, which extend axially, passing through slots separating the fingers 11 in pairs, and which are circumferentially cantilevered, parallel to the collar d support 14, retaining fingers forming a retaining shoulder 22 as described in the document
FR-A-2 544 036.

 As a variant, the lugs 21 can carry, at their free end, a Belleville washer, with pinching of the fingers 11 between said washer and the collar 14 as described in document FR-A-2 630 174.

 As a variant, it is possible to use a corrugated elastic washer extending vis-à-vis the flange 14 and coming to be hooked thereon by means of axial tabs passing through the diaphragm, which said washer has.

 The clutch release bearing 1 comprises, on the one hand, a driving element 23 constituted by a ball bearing of which, here, the inner ring 24 is sufficiently extended to penetrate inside the bush 15 and, on the other hand part, an operating element 25 carrying the bearing 23.

 The rotating inner ring 24 therefore constitutes a projecting nose of the driving element 23.

 The driving element 23 is adapted to act in traction on the internal face of the declutching device 11 via the docking piece 13 and has for this purpose a groove 2 for receiving, described below, from the 'member 16. The operating element 25 is here in the form of a sleeve internally carrying a sleeve 26 made of anti-friction material for sliding along a guide tube (not shown) secured to the gearbox.

 The sleeve 26 is shouldered and has at one of its ends a groove for receiving a circlip allowing its axial setting on the sleeve (Figure 1). The sleeve 25 is suitable for being maneuvered by a clutch release fork and has for this purpose, transversely at its rear end, two tabs 27 each coated with an anti-wear pin 28, for pressing the fingers of said fork. At its front end, the sleeve has an annular transverse flange 29.

 The stop 1 is here with self-centering maintained and a metal cover 30 axially couples the sleeve 25 to the non-rotating external ring 31 of the bearing 23.

 This cover 30, comprising a dropped edge 32 directed towards the axis of the assembly, is crimped onto the flange 29 and an elastic washer with axial action 33, here a wavy washer as a variant a Belleville washer, is supported on the flange 29 and on the relevant edge of the ring 31 to urge the other edge of the ring 31 in contact with the fallen edge 32.

 The cover 30, in a manner known per se, surrounds the outer ring 31 with radial clearance, to allow movement of the bearing 23 and self-centering of the stop 1.

 The rotating ring 24 of the attack element 23 has a groove 2 for receiving the coupling member 16. This groove 2, formed in the nose of the attack element 23, has a flank 3 of action.

 After snap-fitting of the stop on the docking assembly constituted by the docking piece 13 and the coupling member 16, the stop 1 by its driving element 23 is adapted to act in traction on the internal face of the declutching device 11 via the docking piece 13, the member 16 being wedged between the sidewall 3 and the shoulder 18 of the sleeve 15 forming a drive surface, here of frustoconical shape.

 Here the member 16 is permanently wedged between the sidewall 3 and the drive surface 18 by means of elastic holding means 4.

 The coupling of the stop 1 to the part 13, by joining in traction using the member 16, is thus carried out axially in both directions.

 According to the invention, a stop of the above-mentioned type is characterized in that the groove 2 of the nose 24 of the attack element 23 is extended on the side opposite its action flank 3, for mounting in advance by at least an elastic washer 5,6 with axial action constituting the elastic holding means 4.

 In FIGS. 1 to 4, the groove 2 is extended on the side opposite to its action side 3, for mounting in advance of at least two elastic axial action washers mounted in series, said washers constituting the elastic holding means 4 .

 These washers 5,6 act between the edge of the free end of the bush 15 and the other flank 7,9 of the groove 2, the washer 5 pressing on the free end of the bush 15.

 Thus during the snap-fit mounting of the stop 1, by relative approximation of the primary and secondary blocks described above, the nose 24 penetrates inside the socket 15, while opening the coupling rod 16. To do this, the front end of the ring 24 has a penetrating shape 8, here frustoconical, which is connected to a guide surface, suitable for cooperating with the reduced diameter portion of the internal bore of the sleeve 15. This cylindrical guide surface is connected to the groove 2, the flank 3 of which is semi-circular to match the shape of the rod 16. Of course, the structures can be reversed, the flank 3 being of frustoconical shape and the drive surface 18 of semicircular shape for marrying the shape of the rod. It all depends on the configuration of the docking room.

 The other flank 7, 9 of the groove has a transverse end or external portion 9 and an internal end or portion 7 inclined towards the flank 3 connecting to the external end by a bend. This arrangement makes it possible to follow the shape of inclined legs 10, which each washer 5, 6 has at its internal periphery, as described below.

 It will be appreciated that advantage is taken of the configuration of the inner ring of the bearing 23, which has a change in diameter. Indeed, the external portion 9 is formed here thanks to this change in diameter and extends radially beyond the sidewall 3.

 Thus during the approximation of the stop relative to the docking part, for example in a manner known per se using the fork pressing on the flange 29 with disconnection of the linkage connecting the fork to the pedal declutching, the front end 8 of the nose 24 penetrates with certainty into the engagement surface 17 of the socket 15, then the movement continuing, the edge of the free end of the socket 15 comes into contact with the washer 5 , while the front end 8 comes into contact with the rod 16.

 During the continuation of the movement (FIG. 3), the compressors 5,6 as well as the elastic washer 33 are compressed using the free end of the sleeve 15, while causing an opening of the rod 16. The movement ends when the two washers 5,6 are fully compressed (Figure 3). Subsequently, a backtracking and a jamming of the rod, between the sidewall 3 and the bearing surface 18, is carried out automatically by the washers 5,6.

 It will be appreciated that it is thus possible to perform an overtravel in order to carry out with certainty the clipping carried out with a large stroke. More advantageously, the external diameter of the washers 5,6 is greater than the external diameter of the free end of the sleeve 15, so that in all certainty these washers 5,6, here of the same load, are compressed by the sleeve 15.

 According to one characteristic, each elastic washer 5,6 has at its internal periphery holding means 10. It may for example be pads attached to the internal periphery of the washers 5,6, but here advantageously these holding means consist of inclined legs 10 in the direction of the action flank 3.

These tabs are tightened, preferably slightly tightened, against the bottom of the groove 2 and are in one piece with the washers 5, 6 being from the internal periphery thereof with the formation of a rounded in the rooting area of the legs 10 to the washers 5,6.

 The tabs 10 allow a refocusing of the washers in operation, the washers 5,6 being self-centering. As a variant, the legs can be square-shaped.

 Thus before mounting the stop (Figure 2), the washers 5,6 are held and centered with certainty in the groove 2. The tabs 10 of the washer 5 bear against the flank 3, while the tabs 10 of the washer 6 conform to the shape of the inclined portion 7 and of the transverse shoulder 9. This arrangement makes the washers 5,6 stable and allows the mounting thereof by axial threading on the nose 24, the tabs 10 retracting naturally by contact with the front end 8 to then be placed in the groove 2. In addition, during assembly the washer 5 slides without problem.

 It will be appreciated that the inclination of the legs 10 is generally equal to the inclination of the engagement surface 17, so that mutual centering of the washer 5 with the sleeve 15 is achieved during assembly and that the tilting of the 5.6 washers is avoided in combination with the side 7.9, both during assembly and operation.

 In the embodiment of Figures 1 to 4, the elastic washers consist of wavy washers directed in opposite directions (Figure 4). The legs 10 come from the tops and hollows of the undulations of the washers 5, 6 flattened for this purpose.

 More specifically, the washers 5,6 are mounted head to tail while being in contact with one another. These washers are identical, one of them being angularly offset with respect to the other, so that the vertices of one of the washers come into contact with the hollows of the other washer.

 As can be seen in FIG. 4, the vertices and the hollow of the washers are flattened, to form flat zones, so that a good contact zone is obtained between said washers, by shifting the vertices 70 from one of the washers to bring them into contact with the recesses 80 of the other washer.

 As a variant, identical washers may only have tabs at their hollows or tops.

 To avoid any relative movement between the two washers 5 and 6, which would destroy the series mounting of the washers, we can stick them at their node (or contact area) or alternatively (Figure 5) weld them (reference 140) at the level of their flattened nodes.

Thus the washers 5,6 are angularly indexed with respect to each other, while being linked in rotation.

This indexing can also be carried out using additional tabs 100, 101 (FIGS. 6 and 7A, 7B), which each washer 50, 60 has.

 Thus each washer has circumferentially alternating legs 101 and 100. The legs 101 are longer than the legs 100, each leg 101 of a washer being suitable for nesting between two legs 100 of the other washer (FIG. 7A and 7B).

 Thus the washers 50,60 can be identical, being offset circumferentially with respect to each other, the flat vertices 170 of one of the washers coming after rotation into contact with the hollow planes 180 of the other washer. To do this, each washer has at its flat tops two legs 101 and at its hollows a tab 100 adapted to be inserted between the legs 101, as visible in FIGS. 7A and 7B. The mounting of the indexed washers by rotation is done by simple approximation of one washer relative to the other, the legs 100 being advantageously chamfered and engaging between two legs 101.

 Thus any relative rotation between the washers 50 and 60 is avoided.

 It will be noted that the tabs 100, 101 also form retaining tabs outside the contact zones of the washers.

 Of course, the elastic washers can consist of washers of the Belleville 51.52 type (FIG. 8) with lugs 200 at their internal periphery inclined in the direction of the sidewall 3 as before.

Said elastic washers being mounted back-to-back in the opposite direction (or head to tail) and bearing on the free end of the sleeve 15 and on the side 7,9.

 The washers 51, 52 are inclined in the opposite direction while being in contact with one another at their outer periphery.

 Here the load exerted by the washers 5,6, 51,52 is less than the opening force of the rod, so that said washers are compressed first with the formation of a stop for opening thereafter of the rod 16 The load of these washers is here less than the load exerted by the self-centering spring 33 which is compressed during assembly, the fingers 22 coming into contact with the diaphragm 11 (FIG. 3) with the appearance of a play between the diaphragm 10 and the flange 14 during assembly, which constitutes a natural stop.

 Of course, the reverse arrangement is possible, the load exerted by the elastic washers being able to be greater than the opening force of the rod by contact with the end 8. All of this depending on the applications and said force. Likewise, the load on the washer 33 may be less than the load on the washers 5,6.

 Of course, the present invention is not limited to the embodiments described. In particular, the structures can be reversed as described in application FR 91 11444 filed on September 19, 1991 and not published to date.

 In this case, the outer ring is rotating and a housing is attached by crimping on said outer ring, said housing being shaped to have a nose with the groove according to the invention. In this case the internal ring is non-rotating with a self-centering link between it and the sleeve.

 The stop can be of the hydraulic type as described in application FR 91 13477 filed on October 31, 1991 and not published to date.

 In this case the sleeve forms the control piston slidingly mounted on an axially fixed cylinder and replacing the declutching trumpet. In this case, if the preload spring, usually integrated in the control, no longer has its effects on the piston (stress in the direction of traction), unclipping of the stop is not to be feared.

 It is possible to mount more than two washers in the groove 2, and the loads of the washers 5,6-50,60 can be different. The washers can be separate from each other. Thus with reference to FIG. 4, one of the washers would have legs inclined at its apices and the other of the legs inclined in its hollows, the contact areas being devoid of legs.

 A screen washer 240 can be mounted between the two wavy elastic washers 5,6 (FIG. 9), so that said washers 5,6 are indexed with respect to one another in order to guarantee their assembly in series.

In this case, the washer 240 can also comprise, in one piece, at its internal periphery, retaining and refocusing tabs 300 inclined in the direction of the sidewall 3.

 Finally (FIG. 10) it is only possible to mount a plain elastic washer 500 in the groove 2 and in this case the other side 90 of the groove may have only a transverse bearing 90 connected by a rounding to the bottom of the groove 2 This washer 500 may have tabs at its outer periphery 10. In this case, one of the washers 5,6 in FIG. 1 or one of the washers 50,60 in FIG. 6 can be mounted in said groove 2. which is shortened, said washer intervening between the free end of the sleeve and the other side 90 of the groove.

Claims (17)

 1) Clutch release assembly, in particular for a motor vehicle, of the type comprising a clutch release bearing (1) provided with a driving element (23) with a nose (24), adapted to act in traction on the internal face of a declutching device (10) of a clutch, such as a diaphragm, by means of a docking part (13) preassembled on said declutching device (10), an elastically coupling member (16) radially deformable, carried internally by the docking piece (13), for securing in traction the docking piece (13) to the attack element (23) and elastic retaining means (4) acting axially between the driving element (23) and the docking part (13) for permanently wedging the coupling member (16) between a drive surface (18), which has the internal bore of a socket (15) belonging to the docking part (13), and an action flank (3) of a groove (2) belonging to the nose (24) of the element nt of attack (23) penetrating inside the sleeve (15) of the docking part (13), characterized in that the groove (2) of the nose (24) of the attack element ( 23) is extended on the side opposite the action flank (3), for mounting in advance of at least one elastic washer (5,6-51,5250,60) with axial action, called elastic retaining washer, constituting said elastic holding means (4).  2) abutment assembly according to claim 1, characterized in that the external diameter of said elastic retaining washer is greater than the external diameter of the free end of the sleeve (15) of the docking part (13), said elastic retaining washer acting between the free end of said sleeve (15) and the other side (7, 9) of the groove (2).  3) abutment assembly according to claim 1 or 2, characterized in that the elastic retaining washer (5,6-50,60-51,52) has at its internal periphery holding means, for centering maintenance of said washer in the groove (2) extended from the nose of the attack element (24).  4) abutment mounting according to claim 3, characterized in that said holding means consist of inclined legs (10) in the direction of the action flank (3) of said groove (2).  5) abutment assembly according to claim 4, wherein the sleeve (15) has internally at its free end a frustoconical engagement surface (17), characterized in that the inclination of said inclined legs (10) is generally equal to the inclination of said engagement range (17).  6) abutment assembly according to any one of claims 1 to 5, characterized in that the groove (2) of the nose (24) of the attack element (23) is extended on the side opposite to the flank of action (3), for mounting in advance of at least two elastic washers (5,6-51,5250,60) with axial action, called elastic retaining washer, connected in series and constituting said elastic retaining means (4), said washers acting between the free end of the sleeve (15) and the other flank (7,9) of the groove (2).  7) abutment assembly according to claim 6, characterized in that said elastic retaining washers consist of wavy washers (5,6-50,60) mounted head to tail against each other.  8) abutment assembly according to claim 7, characterized in that said elastic retaining washers (5,6-50,60) are identical to each other, one being angularly offset from the other , so that the tops of one of the washers come into contact with the hollows of the other washer.  9) abutment assembly according to claim 7 and 4, characterized in that said inclined legs (10) come in one piece from the tops (70) and hollows (80) of said corrugated washers (5,6-50, 60).  10) abutment mounting according to any one of claims 7 to 9, characterized in that indexing means are provided for indexing said washers relative to each other and guaranteeing their mounting in series.  11) abutment assembly according to claim 10, characterized in that said indexing means form rotation locking means and consist of securing means, such as gluing or welding (140), said washers (5 , 6) at their contact zones.  12) abutment assembly according to claim 10, characterized in that said indexing means form rotation locking means and consist of inclined legs, which has each retaining washer (50,60) at its areas contact with the other washer, said tabs (100,101) coming to overlap one another, and in that said tabs have different lengths, a long tab (101) of one of the washers cooperating with at least one short tab (100) of the other washer.  13) abutment assembly according to claim 12, characterized in that said elastic retaining washers are identical to each other, each washer having at its vertices two long legs (101) and at its hollows a short leg (100) , so that during assembly, after rotation of a washer with respect to the other, a short tab is inserted between two long legs (101).  14) abutment assembly according to claim 10, characterized in that said indexing means consist of a screen washer (240) interposed between the two corrugated elastic washers (5,6).  15) abutment assembly according to claim 6, characterized in that said elastic retaining washers consist of Belleville washers (51,52) inclined in opposite directions.  16) abutment assembly according to any one of the preceding claims, characterized in that the other flank of the groove (2) of the driving element (24) has externally a transverse portion (9) and an internal portion (7) generally inclined conforming to the shape of the washers.  17) abutment assembly according to claim 11, characterized in that the transverse portion (9) is formed by means of a change in diameter, that has the rotating ring of the bearing (23).