FR2745234A1 - Power transmission drive coupling for automobile - Google Patents

Abstract

The drive coupling is used between a flange (14) of a drive wheel and an output device (12) of the power transmission and employs complementary coupling devices (19) with a crown at the end if the wheel flange facing the output device. having profiles (44) engaging complementary profiles (54) secured to the output device. The power transmission interface of the complementary profiles is distributed around the outside of the end of the wheel flange carrying the crown, with the force transmitted tangentially relative to the movement of the wheel flange.

Description

 The present invention relates to a rotational coupling of a drive wheel flange to an output member of a joint joint of a transmission, in which the wheel flange is mounted for free rotation through a support. wheel via a bearing, the wheel flange and the outlet member of the articulation joint comprising complementary coupling means.

 In a conventional arrangement, the outlet member of the articulation joint is formed by a bowl of a constant velocity joint extended by a fluted wheel flange made in one piece.

 To ensure coupling, the rocket is forced into a pinhole bore of the flange. The flange is secured to the rocket by a nut screwed onto a threaded end portion of the rocket.

 Such an arrangement has several drawbacks.

 The rocket, which runs right through the wheel flange, has a long length which makes it difficult to dismantle the transmission. It is thus often necessary to dismantle almost all of the propulsion half-train of the vehicle in order to replace one of the components.

 Furthermore, the presence of the rocket increases the revolving assembly supported by the bearing. In addition, the forced insertion of the rocket into the spindle bore of the wheel flange leads to an uncontrollable inflation thereof, so that the prior adjustment of the bearing, envisaged without this inflation, is altered, this which affects the reliability of the whole.

 In another known arrangement, which avoids these difficulties, the rocket is eliminated and the complementary coupling means comprise front splines placed at the end of the flange facing the bowl of the constant velocity joint, these splines cooperating with complementary front splines carried by the bowl. The fastening of the flange is ensured by a screw which freely crosses the bore of the flange.

 In this case, the front splines being formed on a circle of small radius, the contact sides of the splines must be inclined in order to avoid destruction of the splines under the effect of the torque. Thus, during the drive, the flange is stressed axially undesirably, tending to move the flange away from the constant velocity joint.

 The object of the invention is to propose a coupling in rotation which does not have, or at least reduces the drawbacks mentioned above and which, in particular, is quickly removable, while ensuring reliable and efficient transmission of the torque.

 To this end, the subject of the invention is a coupling in rotation of a drive wheel flange to an output member of an articulation joint of a transmission, in which the wheel flange is mounted to rotate freely at through a wheel support by means of a bearing, the wheel flange and the outlet member of the articulation joint comprising complementary coupling means, characterized in that said complementary coupling means comprise a crown attached to the end of the flange facing the output member, this crown comprising drive profiles adapted to cooperate with complementary profiles linked to said output member, the force transmission interface of said profiles drive being distributed essentially outside the extension of the end of the wheel flange carrying said crown.

According to particular embodiments, the coupling can include one or more of the following characteristics
- the transmission interface is located substantially opposite the mobile elements of the bearing
the force transmission interface between the drive profiles of the crown and the complementary drive profiles linked to the output member is essentially radial, so that the forces are transmitted essentially tangentially with respect to the movement of the wheel flange
- The drive profiles of the crown have a peripheral toothing and the joint output member has a complementary peripheral toothing, the sides of the teeth of one and the other of the teeth extending substantially radially to ensure dog clutching.
- the toothing carried by said crown is a lateral toothing and the toothing carried by the joint outlet member is a frontal toothing
- The coupling means comprise an axial retaining member which cooperates with said ring and with said outlet member of the articulation joint;
- Said axial retaining member comprises a rod housed in a space delimited by the toothed crown and a complementary crown, in particular provided with teeth, which is coaxially integral with it, a groove for receiving the rod being formed on the inner face of the worn toothing by the outlet member of the articulation joint
- the two crowns are toothed and the teeth of at least one crown are inclined towards the teeth of the other crown to ensure centering and retention of the rod
- Said axial retaining member comprises a rod received in a groove formed in the outer cylindrical surfaces of the complementary teeth
- Said axial retaining member comprises a rod received on the one hand in a first groove delimited by the internal surface of the toothed ring, and on the other hand in a complementary concentric groove arranged opposite said first groove and delimited on a cup centering welded axially at the end of said outlet member
- The crown has at its outer periphery longitudinal grooves, and the outlet member includes similar grooves, said coupling means further comprising an internally grooved sleeve in which are fitted the grooved portions of said crown and said outlet member
- An axial retaining ring is received on the one hand in a groove formed in said crown and on the other hand in a concentric groove arranged opposite and formed in said member for leaving the articulation joint
- the flange has annular raceways on the outside for the movable elements of said bearing and said ring is welded along the front end of said flange
- The flange is axially hollowed out and has annular raceways on the outside for the movable elements of said bearing and the crown has at its inner periphery a re-entrant collar according to which it is welded to the flange in the central hollowed out part thereof.
- The bearing has an inner ring secured to said flange and said crown is welded to the front face of the inner ring of the bearing
- the inner ring of the bearing has two rings joined axially and the ring on which the crown is welded is directly welded to the flange
- the ring attached to the ring on which the crown is welded came integrally with the flange and
- The inner ring of the bearing has two rings joined axially and the ring on which the crown is welded is welded to the complementary ring according to their contact surfaces, said complementary ring being welded to the flange.

The invention will be better understood on reading the description which follows, given solely by way of example and made with reference to the drawings in which
- Figure 1 is a half view in longitudinal section of one end of a transmission associated with a drive wheel of a motor vehicle showing a coupling according to the invention;
- Figures 2 and 3 are alternative embodiments of the arrangement of Figure 1, in which the raceways of the ball bearing are delimited by attached rings
- Figures 4, 5 and 6 are views in longitudinal section of details of alternative embodiments of the embodiment of Figure 1;
- Figure 7 is a partial longitudinal sectional view of the end of a transmission associated with a drive wheel of a motor vehicle and comprising a coupling according to the invention, the transmission being shown coupled and uncoupled; and
- Figure 8 is a half-view in longitudinal section of the end of a transmission associated with a drive wheel of a motor vehicle and comprising a coupling according to the invention according to yet another embodiment.

 The arrangement shown in FIG. 1 essentially comprises a constant velocity joint 10 provided with a bowl 12, a wheel flange 14, a wheel support 16, a ball bearing 18 and complementary coupling means 19 of the flange 14 in bowl 12. This arrangement is generally of revolution of axis XX.

 The flange 14 has the general shape of a sleeve of revolution around the axis X-X. At its rear end, that is to say the end opposite to the constant velocity joint 10, it comprises externally an annular flange 20 provided with tapped holes 22 for receiving the wheel fixing bolts (not shown). Or the inner ring (s) of the bearing 18 coming integrally with the flange, the latter also has, on an external cylindrical surface 24, a peripheral groove 26 of oblong section with rounded edges forming rolling and abutment paths for balls 28 of the bearing, distributed in two rows.

 The bearing 18 includes an outer ring 30, as well as a not shown ball spacer. The bearing 18 and the flange 14 are received in a through bore 32 of the wheel support 16. The outer ring 30 is held axially on either side by circlips 34, 36 received in annular grooves opening onto the surface of the bore 32. Thus, the flange 14 is mounted to rotate freely relative to the wheel support 16.

 Furthermore, linings 37A, 37B are provided on either side of the bearing 18 to protect the latter.

 The constant velocity joint 10 is partially shown. It comprises for example a core 38 received at the end of a driving shaft. The grooves of this core cooperate by means of balls with grooves in the bowl 12.

 The complementary coupling means 19 comprise a first toothed ring 40 welded to the front end of the flange 14 in a frontal weld 41. This first ring 40 is formed by an annular sheet blank whose inner periphery is bent to follow the inner profile of the flange thus forming a collar 42. On its outer periphery, the ring 40 has a lateral toothing 44 with radiating teeth facing outwards. This toothing has a diameter greater than that of the front end of the flange. The flanks of the teeth of the teeth 44 extend substantially radially, that is to say in planes containing the axis X-X.

 A second toothed crown 46 is welded coaxially to the first crown 40. It has an external peripheral toothing 48 with teeth similar to those of the toothing 44. Its internal periphery 50 along which it is welded to the crown 40 is offset axially, from so that the concentric toothed rings 40 and 46 delimit between them an annular space 52.

 The complementary coupling means 19 also comprise a front toothing 54 formed integrally with the bowl 12. This toothing 54 is adapted to cooperate with the toothing 44 and 48 by ensuring dog clutching. Thus, the sides of the teeth of the toothing 54 extend substantially radially, that is to say in planes containing the axis X-X. In addition, the inner end of the teeth of the toothing 54 is bevelled, to facilitate its mounting.

 On its inner cylindrical wall, the toothing 54 has a peripheral groove 56. When the flange 14 and the bowl 12 are coupled, a rod 58 is received between the two toothed rings 40, 46 in the space 52, and is partially housed in the groove 56. This rod has a thickness substantially equal to the width of the space 52 and provides an axial retention between the flange 14 and the bowl 12.

 In order to proceed with the mounting of such a coupling, the packing 37A, the circlip 36, the two rows of balls 28 as well as the outer ring 30 are first placed on the flange 14. The rings 40 and then are welded coaxially. 46 at the front end of the flange 14, the rod 58 being previously disposed between the two rings in the space 52. The assembly thus formed is disposed inside the wheel support 16 then the circlips 34 and 36 are put in place, retaining in translation the flange 14 relative to the wheel support 16. The bowl 12 of the constant velocity joint is then brought axially against the flange. When the bowl 12 is sufficiently engaged, the complementary teeth of the coupling means 19 engage and the rod 58, after being retracted at the bottom of the space 52 under the action of the beveled end of the teeth 48 , snaps into the groove 56 thus ensuring axial retention of the flange 14 and the bowl 12.

 It is understood that with such an arrangement, the transmission of the torque between the bowl 12 and the flange 14 is effected by clutching essentially tangentially with respect to the rotational movement of the flange. This transmission is effected along the radial sides of the complementary teeth.

 Under these conditions, no axial force arises between the flange 14 and the bowl 12 so that the rod 58 is sufficient for the axial retention.

 Furthermore, the torque transmission interface being distributed essentially outside the extension of the end of the flange, and in particular facing the balls 28 of the bearing, the torque can be transmitted satisfactorily, without risk for the teeth of the toothed crowns, these teeth being distributed over a circle of larger diameter than the end diameter of the flange 14. Thus, the radial sides of the teeth do not undergo any degradation, the force applied to each tooth for a given torque being more low than the force which would have been applied if the torque was transmitted on a gear ring of smaller diameter placed in the extension of the end of the flange.

 In addition, the teeth being distributed over a circle of larger diameter than if they were placed at the end of the flange, the angular clearances between the teeth in engagement are lower for the same manufacturing tolerance as for teeth produced at the end of flange on a circle of smaller diameter.

 In Figure 2 is shown an alternative embodiment of the device of Figure 1. In this embodiment, the inner ring of the ball bearing 18 consists of two rings joined axially, denoted 60 and 62. Each ring carries a path bearing for one of the rows of balls 28. The flange 14 has on its outer surface 24 a peripheral clearance 64 for receiving the rings 60 and 62.

 In this embodiment, the rear ring 62 is fitted on the flange 14 in the clearance 64 and is pressed against a front 66. This ring 62 is welded along its cylindrical surface in contact with the flange 14, for example by laser welding. The resulting weld is noted 68 in this figure.

 The front ring 60 is partially fitted onto the flange 14 and is welded to the rear ring 62 by laser welding, for example along their contacting surfaces, giving rise to a weld 70.

 The first ring gear 40 is welded to the front surface of the front ring 60, for example by laser welding, following a weld 72. In this embodiment, the collar 42 follows the shape of the protruding end of the ring 60 .

 During the drive, the torque from the bowl 12 is communicated from the toothing 54 to the toothed rings 40, 46. The latter transmit the torque to the front ring 60 which itself urges the ring 62 by means of the weld. 70, the ring 62 finally transmitting the torque to the flange 14 by the weld 64.

 FIG. 3 represents another variant of the embodiment of FIG. 2.

 In this figure, the rear ring 62 is not welded to the flange 14. Only the front ring 60 is welded along its cylindrical wall in contact with the flange according to a weld 74 produced for example by laser welding. As before, the ring gear 40 is welded to the front surface of the front ring 60.

 As a variant, the ring 62 can come from the material with the flange 14. The added ring 60 is then welded to the flange along its front surface with the ring 62 from the material or along its cylindrical wall in contact with the flange.

 The arrangement of FIG. 4 differs from that of FIG. 1 only in that the ring gear 40 is not welded to the front end of the flange 14.

In this case, the ring gear 40 is welded to the flange along the collar 42, for example by laser welding, thus giving rise to a weld 76. To do this, the collar 42, engaged in the axial passage of the flange 14, has a length greater than that of the previous embodiments.

In the alternative embodiment shown in FIG. 5, the toothed rings 40 and 46 have come in one piece and are formed by external radial lugs 80, 82, cut from the same blank of annular sheet metal. These legs are pushed back and folded in planes extending substantially parallel. They delimit between them the space 52 for receiving the rod 58. Furthermore, the toothing 44 is inclined towards the toothing 56 in order to close at its outer end the space 52, thus trapping the rod 58. The inclination of the toothing 44 is such that the rod 58 comes to bear against the latter, thus ensuring its centering with respect to the axis
XX.

 In FIG. 6, the coupling means 19 comprise a toothed ring 90 formed by a flat sheet welded to the front end of the flange 14. In this embodiment, the toothed ring 90 has a counterbore 92 at its inner periphery , delimiting with the end face of the flange 14 a groove 94.

 Furthermore, a centering cup 96 is welded in an annular weld 98 at the end of the bowl 12. It has a groove 100 formed by a fold of the sheet metal constituting it. This groove 100 extends opposite the groove 94. A rod 102 is received at the interface between the concentric grooves 94 and 100 in order to ensure axial retention of the bowl 12 relative to the flange 14.

 The centering cup 96 has behind the groove 100 a frustoconical portion 104 whose diameter of the part bordering the groove 100 is substantially equal to the inside diameter of the flange 14. Thus, when the bowl 12 is brought closer to the flange 14, this frustoconical portion 104 ensures centering of the bowl 12 relative to the flange. Furthermore, this section 104 pushes the rod 102 inside the groove 94 during assembly of the coupling.

 In this embodiment, the small diameter of the rod 102 provides it with high resistance to forces along the axis XX, so that the axial retention of the flange 14 and the bowl 12 is more resistant than in the embodiments. embodiment described above in which the rod has a large diameter.

 In the embodiment shown in FIG. 7, the outer ring of the bearing 18 has come integrally with the wheel support 16.

 Furthermore, the complementary coupling means, shown in the upper part of the axis in the coupled position and in the lower part in the uncoupled position, comprise a thick toothed ring 110 welded to the front end of the flange 14 according to a weld frontal 112. As before, the crown 110 has an outer peripheral toothing 114, of outer diameter greater than the diameter of the front end of the flange 14. The toothing 114 has a width (measured along the axis XX) greater than the width of the crown 110 measured at its inner periphery.

 In this embodiment, the bowl 12 has a front toothing 115 adapted to cooperate with the toothing 114. An outer peripheral groove 116 is formed both on the toothing 114 and on the toothing 115. This groove opens onto the surface cylindrical outer of these teeth. A rod 118 is received inside the groove 116 in order to ensure axial retention of the flange 14 and the bowl 12.

 A ring 120 is further fitted on the complementary teeth 114, 115 and covers the groove 116 to protect and maintain the rod 118 received therein. The ring 120 is put in place by forced displacement in the direction of the axis X-X.

 The advantages stated with regard to the embodiment of FIG. 1 are found in the alternative embodiments of FIGS. 2 to 7.

 In the variant embodiment shown in FIG. 8, the flange 14 is secured at its front end to a rotational drive ring 122.

The latter has a substantially S-shaped shape in radial section. A first inner wing defines a collar 124, introduced into the central passage of the flange 14. The crown 122 is welded along this collar 124 on the inner cylindrical surface of the flange 14 following a weld 126. The second wing of the crown in S 122 defines a collar 128, the diameter of which is greater than the end diameter of the flange 14. The collars 124 and 128 are linked by an annular core 129 extending radially with which they came from matter at each end. The collar 128 carries on its outer cylindrical surface longitudinal grooves 130. Furthermore, a groove 132 is formed on the inner surface of the collar 128.

 The bowl 12 has on its outer cylindrical wall longitudinal grooves 134 similar to the grooves 130 of the crown 122. An internally grooved sleeve 136 surrounds the grooved sections 130 and 134, thus ensuring a rotational connection of the bowl 12 and the flange 14 by cooperation of the grooves of the sleeve 136 with the grooved sections 130 and 134.

 Furthermore, a groove 138 is formed in the bowl 12 facing the groove 132. A rod 140 is disposed between these two concentric grooves so as to ensure axial retention of the bowl 12 and the flange 14.

 When mounting the coupling, the rod 140 retracts to the bottom of the groove 138 under the action of the front edge of the collar 128.

 In this embodiment, it is understood that the sleeve 136 allows a coupling in rotation of the bowl 12 to the flange 14 with a transmission of the forces essentially tangential with respect to the direction of rotation of the flange 14.

 Whatever the embodiment, the coupling allows quick and easy assembly and disassembly.

Indeed, for disassembly of the transmission, it is not necessary to extract the wheel flange 14 from the wheel support 16, thanks to the short axial length of the coupling means.

 Likewise, the coupling can be mounted while the flange 14 is already in place in the wheel support 16.

Claims (18)

 1.- Rotational coupling of a drive wheel flange (14) to an output member (12) of a joint joint of a transmission, in which the wheel flange (14) is mounted to rotate freely through a wheel support (16) by means of a bearing (18), the wheel flange (14) and the outlet member (12) of the articulation joint comprising coupling means complementary (19), characterized in that said complementary coupling means (19) comprise a crown attached to the end of the flange facing the outlet member (12), this crown (40, 46; 90; 110; 122) comprising drive profiles (44, 48; 114; 130) adapted to cooperate with complementary profiles (54; 115; 134, 136) linked to said output member, the force transmission interface of said drive profiles (44, 48; 114; 130) being distributed essentially outside the extension of the end of the wheel flange (14) in. re said crown (40, 46; 90; 110; 122).  2. A coupling according to claim 1, characterized in that the transmission interface is located substantially opposite the movable elements of the bearing (18).  3.- Coupling according to claim 1 or 2, characterized in that the force transmission interface between the drive profiles (44, 48; 114; 130) of the crown and the complementary drive profiles (54 ; 115; 134, 136) linked to the output member (12) is essentially radial, so that the forces are transmitted essentially tangentially with respect to the movement of the wheel flange (14).  4- coupling according to claim 3, characterized in that the drive profiles of the crown have a peripheral toothing (44, 48) and the outlet member (12) of the joint has a complementary peripheral toothing, the sides of the teeth of one and the other of the teeth extending substantially radially to ensure interconnection.  5. A coupling according to claim 4, characterized in that the toothing (44, 48) carried by said crown (40, 46) is a lateral toothing and the toothing (54) carried by the outlet member (12) of the joint is a front toothing.  6.- Coupling according to claim 5, characterized in that the coupling means (19) comprise an axial retaining member (58, 102, 118, 140) which cooperates with said crown (40, 46) and with said member outlet (12) of the articulation joint.  7. A coupling according to claim 6, characterized in that said axial retaining member comprises a rod (58) housed in a space (52) delimited by the toothed crown (40) and a complementary crown (46), in particular provided with teeth, which is coaxially integral with it, a groove (56) for receiving the rod being formed on the inner face of the toothing (54) carried by the outlet member (12) of the articulation joint.  8.- Coupling according to claim 7, characterized in that the two crowns (40, 46) are toothed and the toothing (44) of at least one crown (40) is inclined towards the toothing (48) of the other crown (46) to ensure centering and retention of the rod (58).  9. A coupling according to claim 6, characterized in that said axial retaining member comprises a rod (118) received in a groove (116) formed in the outer cylindrical surfaces of the complementary teeth (114, 115).  10. A coupling according to claim 6, characterized in that said axial retaining member comprises a rod (102) received on the one hand in a first groove (94) delimited by the inner surface of the ring gear (90), and on the other hand in a complementary concentric groove (100) disposed opposite said first groove (94) and delimited on a centering cup (96) welded axially at the end of said outlet member (12).  11.- Coupling according to claim 3, characterized in that the crown (122) has at its outer periphery longitudinal grooves (130), and the outlet member (12) comprises grooves (134) similar, said means d coupling further comprising an internally grooved sleeve (136) in which the grooved portions (130, 134) of said ring (122) and of said outlet member (12) are fitted.  12. A coupling according to claim 11, characterized in that a rod (140) of axial retention is received on the one hand in a groove (132) formed in said crown (122) and on the other hand in a concentric groove (138) disposed opposite and formed in said outlet member (12) of the articulation joint.  13.- Coupling according to any one of the preceding claims, characterized in that the flange (14) has outwardly annular raceways (26) for the movable elements (28) of said bearing (18) and said crown (40) is welded along the front end of said flange (14).  14.- Coupling according to any one of the preceding claims, characterized in that the flange (14) is axially hollowed out and has externally annular raceways (26) for the mobile elements (28) of said bearing (18), and in that the crown (40) has at its inner periphery a re-entrant collar (42) along which it is welded to the flange (14) in the hollowed-out central part thereof.  15.- Coupling according to any one of claims 1 to 12, characterized in that the bearing (18) comprises an inner ring (60, 62) secured to said flange (14) and said crown (40) is welded to the front face of the inner ring (60) of the bearing.  16.- Coupling according to claim 15, characterized in that the inner ring of the bearing comprises two rings (60, 62) joined axially and the ring (60) on which is welded the crown (40) is directly welded to the flange ( 14).  17.- Coupling according to claim 16, characterized in that the ring (62) attached to the ring (60) on which is welded the crown (40) came integrally with the flange.  18.- Coupling according to claim 15, characterized in that the inner ring of the bearing comprises two rings (60, 62) joined axially and the ring (60) on which is welded the crown (40) is welded to the complementary ring ( 62) according to their contact surfaces, said complementary ring (62) being welded to the flange (14).