FR2629885A1 - Clutch release bearing assembly particularly for a motor vehicle - Google Patents

Abstract

The present invention relates to a clutch release bearing assembly including a clip 41 and a retaining groove 43 which is provided with an oblique flank 45 and with a bottom 44. According to the invention, the oblique flank 45 of the groove 43 is connected at its bottom 44 by a discontinuity 47 so that the extension 48 of the oblique flank 45 penetrates inside the bottom 44. Application: motor vehicles.

Description

 The present invention relates to a clutch release bearing assembly, in particular for a motor vehicle, of the type comprising for coupling a clutch release bearing to the clutch disengaging device, a docking part provided with a support flange. , for action on the declutching device, and means for securing in traction, which, established between the docking part and the declutching stop, are capable of ensuring an axial connection between said parts in the axial direction going from the declutching device to said declutching stop, said means for securing in traction comprising, on the one hand, an annular rod elastically deformable radially, which is, at least partially, engaged radially in a retaining groove formed for it on any one of said part d docking and declutching stop, and, on the other hand, a drive surface formed on the other thereof, and with which said connecting rod cooperates axially bearing in the axial direction considered.

 The retaining groove can be of the type disclosed in application FR-A-25 44 039 and include an oblique flank or ramp.

 The clutch release bearing has a driving element and an operating element. It is between the attack element and the docking piece that the rod is established, while the operating element is intended to be subjected to the action of a displacement control means such as a clutch release fork; said maneuvering element having an axial passage for its engagement and sliding on a fixed guide coaxial with tolerances close to the axis of the clutch.

 I1 happens that the mounting offset between the axis of the guide and the axis of the declutching device is an offset in orientation, these axes making for example a slight angle between them.

 I1 also happens that during a declutching the declutching device does not exactly form the envelope of a cone, some of the fingers or levers which it comprises being able to be offset with respect to the others, in particular because of manufacturing tolerances.

 For one and / or the other of these two reasons, during a declutching, there is a nutation or "swiveling" movement of the docking part relative to the declutching stop. I1 results in constraints for the clutch release bearing as well as a risk of separation of the stop relative to the docking part.

To overcome these drawbacks, provisions of the type disclosed in the application can be adopted.
FR-A- 22 12 003 with at least one radially elastically deformable belt, said belt being associated with the axial passage of the guide and having at rest an engagement diameter less than the diameter of said axial passage.

 It is therefore away from the means of securing in traction that the belt would be established.

 Contrary to the teaching of this document, the plaintiff wondered if it was not possible to act at the level of the means of securing in traction.

 Since the axial length of the attack element is not negligible, the applicant then posed the problem of overcoming the drawbacks of the prior art by acting at the level of the means of securing in traction, without increasing the axial length of the stopper and while providing other advantages.

 According to the invention, an abutment assembly of the above-mentioned type, in which the side of the retaining groove which is axially on the side opposite to the drive surface relative to the retaining ring, is generally oblique on the axis of the assembly, moving away from the other of the sides of said retaining groove away from said axis, is characterized in that the oblique flank is connected to the bottom of the retaining groove by a discontinuity, so that the extension of the oblique flank penetrates inside the bottom.

 Transversally the oblique flank therefore forms with the bottom a line broken by a break and the length of the retaining groove is reduced.

 Thanks to the invention, the slope of the oblique flank can be relatively small without increasing the axial size of the stop.

 It will be appreciated that a slight slope increases the freedom of movement of the docking part relative to the stop.

 Thus, the contact of the rod with the oblique flank is comparable to a contact of a torus on a sphere so that the docking part can swivel relative to the stop. The stresses undergone by the stop are reduced, which is advantageous in the case where the driving element of the stop is a ball bearing, the life of the latter is thus increased.

 Of course, the abutment mounting is dimensioned so that the average position of the rod corresponds to the middle of the oblique flank, the length of the latter taking account of the extreme positions occupied by the docking part during disengagement.

 In the case where elastic retaining means are provided, which permanently urge the support flange of the docking part in the direction of the declutching device by bearing on a shoulder carried by the declutching stop, advantageously the elastic means of holding are carried by the docking piece and the shoulder is formed on a support piece separate from the docking piece and carried by the clutch release bearing being axially wedged at least in one direction thereon.

 As will be understood by referring to Figures 3 or 6 of application FR-A 2 544 039, and for the same slope of the trpnconic flank, the groove according to the invention leads to a reduction in the length of the inner ring of the stop so that the use of the elastic retaining washer of Figures 3 or 6 of the aforementioned request is made difficult or even impossible given the overtravel that it is necessary to perform the assembly.

 With the above arrangement, mounting is made possible.

 In addition, the support piece can be used to retain the rod before mounting so that the length of the docking piece can be reduced.

The appended description illustrates the invention with reference to the appended drawings in which
- Figure 1 is an axial sectional view of a stop assembly according to the invention, after assembly of the assembly.

 - Figure 2 is a half-view similar to Figure 1 before assembly of the assembly.

 - Figure 3 is a view similar to Figure 3 during the overtravel to perform for the assembly of the assembly.

 As illustrated in these figures, it involves coupling a clutch release bearing 10 to the clutch release device 11 of a clutch.

 Here the declutching device 11 is formed by the end of the fingers 12 of a diaphragm.

 For coupling the stop 10 to this declutching device, there is attached to it a docking part 13. This part 13, of annular shape, has a support flange 14 radially and, in one piece with this collar 14, a sleeve 15 of axial orientation penetrating into the central opening of the diaphragm by crossing the latter.

 The flange 14, which extends from the side of the device 11 opposite the stop 10, is here curved for bearing on the fingers 12 planes. Of course, the reverse is possible, the flange 14 being flat and the fingers 12 bulging.

 The sleeve 15 has, on the side of the stop 10, a frustoconical engagement surface 20 which, oblique to the axis of the assembly, moves closer to said axis away from the stop 10.

 It also has a shoulder 21 forming a drive surface.

 The stop 10 is similar to that of application FR-A2 544 039.

 As a reminder, it will be recalled that it is provided with a driving element 23 constituted by a ball bearing of which, here, the inner ring 25 is sufficiently extended to penetrate inside the sleeve 15, and an operating element 26 which we see in 27 the flange.

This operating element 26 comprises a sleeve by which it is able to slide on a declutching trumpet 31 forming a guide. As a variant, the operating element can slide on balusters carried by the gearbox casing.

 Anyway, this element 23 is adapted to be actuated by a control member such as a clutch release fork.

 Here the stop 10 is self-centering maintained and a sleeve 29 couples the element 26 to the outer ring 30 of the bearing 23. This sleeve 29 is here crimped onto the flange 27.

 An elastic element 34, a wavy washer, only shown in FIG. 1, bears on the flange 27 and urges the ring 30 in the direction of the fallen edge of the sleeve 29, by surrounding the ring 30 for self-centering of the stop.

 A radially elastically deformable coupling member 41 is established between the docking piece 13 and the stopper 10. This is a joining ring with a circular transverse contour opened by a slot. This rod, as described in application FR-A 2 544 039, is engaged in an annular retaining groove 43. The bottom 44 of this groove has, in section, a shape complementary to that of the rod. One of the sides 45 of the groove 43 is oblique and widens the groove 43, while the other is vertical. Note that the shoulder 21 follows the shape of the rod 41 and constitutes a drive surface.

 The retaining ring 41, the retaining groove 43 and the drive surface 21 form means for securing in traction established between the docking piece 13 and the stop 10. They provide an axial connection between the docking piece 13 and the stop 10 in the axial direction going from the declutching device 11 to the stop 10.

 More specifically, the sidewall 45 which is axially on the side opposite to the drive surface 21 relative to the fastening ring 41 is generally oblique on the axis of the assembly, away from the other 46 from the sides of said retaining groove away from said axis.

 According to the invention, the oblique flank 45 is connected to the bottom 44 by a discontinuity 47 so that the extension 48 of the oblique flank penetrates into the bottom.

 The flank 45 or ramp therefore does not connect tangentially to the bottom 44 and the oblique flank 45 forms, in section, with the bottom 44 a line broken by a break.

 The discontinuity 47 forms a radially projecting lip. This lip interrupts the transversely semi-circular contour of the bottom 44.

 Thus the flank 45 approaches the other flank 46, which is generally transverse to the groove 43.

 The flank 45 can therefore have a slight slope of the order of 30, without increasing the length of the groove 43, so that the contact between the rod 41 and the oblique flank 45 is comparable to the contact of a sphere with a torus. When disengaging, the friction plate being released, the docking piece 13 can pivot relative to the stop 10. Thus the defects due to the diaphragm fingers (in particular to the fact that the ends of the fingers 12 are not all in the same plane), as well as the misalignment of the axis of the declutching device 11 (centered on the motor shaft) and the axis of the guide 31 (centered on the gearbox) will generate minimal stresses on the bearing 23.

 Elastic holding means 50, carried by the docking piece 13, bear on a shoulder 65 formed on a support piece 60 distinct from the docking piece 13 and carried by the clutch release bearing 10 while being axially wedged at least in one direction on it.

 More specifically, the docking piece 13 has at its outer periphery a plurality of axial tabs 51.

These pass through the declutching device 11 thanks to the slots existing between the fingers 12 of the diaphragm.

 Before assembling the stop 10 to the docking piece 13 (FIG. 2), the elastic means 50 bear on a shoulder 53 carried by the end of the lugs 51. Here these are notches and the elastic means 50 consist in two Belleville 54.55 washers mounted back to back and therefore in series. Each of these has a continuous internal part 56 and an external part fragmented into legs 57. The width of the legs 57 is greater than that of the fingers 12 and it is these which are intended to cooperate with the notches 53.

 I1 is possible to engage these washers 54,55 axially, in the direction of the device 11, and to deform the lugs 57 to cross the notches 53. It will be noted that the lugs 51 are used for centering the washers 54,55.

 The washers 54, 55 therefore ensure before assembly, by cooperation with the notches 53, a coupling without play of the docking part 13 to the diaphragm 11, said part 13 being centered by its legs 51 on the diaphragm.

 The support piece 60, of annular shape, is slidably mounted on the inner ring 25. It is relatively thick and its main part 61 is made of reinforced plastic, for example by glass fibers, for good sliding of the piece 60 and a reduction in the weight thereof. This part 61 is secured, by riveting, overmolding or the like, to a rounded metal piece 62 for support of the washer 55 furthest from the fingers 12 and therefore formation of the shoulder 65. This support piece 60 has a recess 63 of complementary shape at the end of the sleeve 15 for penetration thereof as described below.

 It will be noted that the part 60 generally forms a ring, which extends radially below the axial lugs 51, and that after assembly it enters the overall volume delimited by the lugs 51.

 This arrangement in combination with the groove according to the invention promotes a reduction in the axial size of the stop assembly. The external periphery of the part 60 here extends radially at the level of the ring 30, below the external periphery of the latter. It therefore constitutes a protective screen.

 As can be seen in the figures, the shoulder 65 forms an axial projection with respect to the part 61 and extends to the external periphery of the part 60, radially beyond the sleeve 15, generally vis-à-vis the convex support zone of the collar 14 on the fingers 12.

 The dorsal face of this piece 60 is hollowed out at 64 for cooperation with a shoulder 70 carried by the ring 25. This shoulder axially wedges the support piece in the direction going from the fingers 12 to the stop 10 and, consists of a circlip 70 engaged in a groove 71 that has the ring 25 in the vicinity of the deflector 72 of the bearing. This circlip 70 offers the part 60 a good range and is relatively thin. I1 is protected by the recess 64.

 The internal bore of the part 60 has a variation in diameter so that a shoulder 73 is formed, the portion of smallest internal diameter being the furthest from the deflector 72.

The assembly is carried out as follows
In FIG. 2, the washers 54, 55, bearing one on the other at their internal periphery, bear at their external periphery respectively on the fingers 12 and the notches 53. The part 60 is it abutted by its shoulder 73 against the end portion of the vertical wall of the groove 43.

 I1 is then possible to open the rod 41 by mounting it on the frustoconical engagement surface 40 of the end of the ring 25, then to push it until contact with the part 60 which then masks the bottom 44 of the groove 43. It will be noted that a visual check is possible before assembly and that the rod 41 is kept precentred between the front end of the part 60 and the ramp 45 of the groove 43. A displacement of the part 60, after introduction of the rush, is therefore impossible.

 During assembly, the bearing surface 20 is allowed to cooperate with the engagement bearing surface 40 of the ring 25. The approximation of the docking part relative to the stop 10 being continued, this corresponding to an approximation of the bearing motor the clutch and therefore the part 13, relative to the gearbox carrying the stopper 10, the bearing surface 20 is allowed to bitter on the rod 41 by closing it, while the washer 55 comes into contact with the part 62 and its shoulder 65. Continuing the movement, the docking piece 13 pushes the piece 60 through the rod 41, the shoulder i3 crossing the stop formed by the end, chamfered, of the vertical part 46 of the groove 43 Note that there is a blooming of the part 60 facilitated by the recess 63 and that the load of the washers 54.55 is sufficient to repel the part 60.

 In the following configurations, the docking piece 13 pushes the rod 41 into the bottom 44 of the groove 43 and moves, thanks to the washers 54, 55, the piece 60 in the direction of the circlips 70.

 In FIG. 3, the part 60 being in abutment on the circlip 70, the washers 54, 55 are flattened by performing an overtravel. During this phase, the free end of the sleeve 15 is allowed to enter the recess 63, while the rod 41 passes behind the drive surface 21.

 By ceasing the action and making a return back, we arrive at the assembly position of FIG. 1. In this position, the rod is in abutment against the ramp 45 while being kept in abutment against the drive range 21 by the washers 54, 55, while a clearance exists between the notches 53 and the washer 55, the circlip 70 being positioned axially accordingly. It should be noted that the break 47 according to the invention does not constitute a hindrance for the assembly thanks to the radial elasticity of the rod 41.

 A reaction action loop is thus formed, the washers 54, 55 supported by their legs 57 on the fingers 12 and the part 62 tending to move the stop 10 away from the docking part 13 for tightening the rod 41 between the groove ramp 43 and drive range 21.

 During operation to disengage, the stop is moved by traction in the opposite direction relative to the disengaging device 11 by driving the docking piece 11 via the ramp 45, the rod 41 and the drive range 21. The average arrangement of the rod 41 after assembly corresponds to that of FIG. 1, the contact with the oblique flank 45 being made in the middle of the latter.

 As is evident from the description and the drawings, the series arrangement of the washers, in addition to good precision of the load exerted, makes it possible to obtain large displacements without excessive effort and therefore a great overtravel for coupling the docking piece 13 to the stop 10, while the recess 63 and the groove 43 promote a reduction in the axial length of the stop. It will be appreciated that the circlip 70 is protected by the part 60 thanks to the recess in the housing 64, the said part 60 forming a protective screen for the deflector 72. Similarly, it will be understood that the inclination of the washer 54 in the direction of the stop 10 clears space for good tilting of the fingers 12. It will be noted that the washers 54, 55 extend radially beyond the sleeve 15 and that the recess 63, matching the shape of the bearing surface 20, delimits with the internal bore of the part 60 an elastically deformable lip.

 Of course, the present invention is not limited to the embodiments described. In particular, the part 60 can follow the shape of the rod 40 to trap it and be metallic or cast iron.

 The docking part can carry the rod as described in Figure 6 of document FR-A-2,544,039.

 In this case the groove 43 is formed in the docking piece 13 and the drive surface 21 is formed in the ring 25. The length of the docking piece, in particular of its socket, is reduced in this case.

 The length of the stopper therefore does not have to be increased.

 The sleeve 15 can be tilted while extending generally axially.

 The elastic retaining member may consist of a corrugated washer provided with axial tabs passing through the diaphragm and engaging by hooking with the rear face of the flange 14. In this case, notches can be provided at the external periphery of the flange 14, these notches having a circumferential width equal to that of the legs. Before assembly, the hooks would be in contact with the docking piece, while after assembly a clearance would exist between said hooks and the docking piece. In this case, the elastic holding means advantageously extend radially beyond the bush 15.

 A single Belleville 54.55 washer can be dimensioned accordingly. The part 60, interposed axially between the fingers 12 and the deflector 72, can carry blades and form a fan.

 The circlip 70, axially integral with the rotating ring 25 thanks to the groove 71, can be replaced by a shoulder formed directly on the ring 25.

 In certain cases, the support piece 60 can carry tongues penetrating into the groove 71 for axial immobilization of said piece.

 The docking piece 13, instead of being made of sheet metal as shown in the embodiment, can be made of cast iron.

 The part 62 is not necessarily curved, it can be flat and the washer 55 can be curved.

 Finally, the groove 43 can be made in the outer ring 30, the ring 25 being in this case non-rotating.

Claims (3)

 1) Assembly of a clutch release bearing, in particular for a motor vehicle, of the type comprising for coupling a clutch release bearing (10) to the clutch disengaging device (11), a docking part (13) provided with '' a support flange (14), for action on the declutching device, and means for securing in traction, which established between the docking part (13) and the declutching stop (10), are capable of ensuring a axial connection between said parts in the axial direction going from the declutching device to said declutching stop, said traction securing means comprising, on the one hand, an elastically radially deformable annular ring (41), which is, at least partially engaged in a retaining groove (43) formed for it on any one of said docking parts (13) and disengaging stopper (10) and, on the other hand, a drive surface (21) formed on the other of these and with which said connecting rod cooperates axially in s the axial direction considered, in which the side (45) of the retaining groove, which is axially on the side opposite the drive surface (21) relative to the retaining ring (41) is generally oblique on the axis away from the other (46) of the flanks of said retaining groove (43) away from said axis, characterized in that the oblique flank (45) is connected to the bottom (44) of the retaining groove by a discontinuity (47), so that the extension (48) of the oblique flank (45) penetrates inside the bottom (44).  2) abutment assembly according to claim 1, characterized in that the discontinuity (47) forms a radially projecting lip.  3) abutment assembly according to claim 1 or 2, in which are provided elastic holding means (54, 55), which permanently urge the support flange (14) in the direction of the declutching device at (11) in bearing on a shoulder (65) carried by the clutch release bearing (10), characterized in that the elastic retaining means (54, 55) are carried by the docking piece (13) and in that the shoulder (65) is formed on a support piece (60) separate from the docking piece (13) and carried by the clutch release bearing (10) being wedged axially at least in one direction thereon.