System for supplying lubricant to a bearing of a motor vehicle gearbox

Abstract

The present invention relates to a system (1) for supplying lubricant to a bearing of a motor vehicle gearbox, comprising a wall (6) configured to partially define a casing (2) of the gearbox, a lubricant distributor and a groove (8) formed in a thickness of the wall (6) and configured to collect lubricant and guide it towards the bearing, the wall (6) lying in a plane defined by a longitudinal direction (L) and a vertical direction (V) perpendicular to the longitudinal direction (L), the groove (8) extending mainly along the longitudinal direction (L), characterised in that the supply system (1) comprises a lubricant guiding device (16) which is positioned at least partially opposite the groove (8) and which is configured to partially close the groove (8).

Description

Description Title of the invention: Lubricant supply system for a bearing of a gearbox of a motor vehicle

[0001] The present invention relates to the field of gearboxes and more particularly to a lubricant supply system within such gearboxes.

[0002] The shafts and gears of a vehicle gearbox, arranged within a suitable casing, must be regularly lubricated in order to keep them in working order. In particular in the case of gearboxes of hybrid vehicles, which have a casing with a volume greater than that known in vehicles with equivalent thermal engines, a specific supply of lubricant may be provided in the gearbox to ensure a supply of lubricant to a particular shaft of said gearbox.

[0003] The gearbox may thus include one or more lubricant supply systems. These systems include in particular a lubricant source and a groove configured to bring the lubricant from the lubricant source to the bearing of the shaft to be lubricated. The lubricant can then spread along the shaft carried by the bearing and then the toothed wheels carried by the shaft.

[0004] Furthermore, the centrifugal force generated by the rotation of the differential crown wheel within the gearbox can generate the projection of drops of lubricant within the gearbox housing. Drops of lubricant are thus projected onto the walls of the housing and the drops projected onto a wall above the groove of a previously mentioned supply system can flow along said wall due to gravity until they reach the groove and thus participate in the supply of lubricant to the bearing arranged at the end of this groove. This additional contribution can represent a significant part of the quantity of lubricant used to lubricate the bearing associated with this groove, and for example of the order of 30%, which makes it possible to limit the consumption of the lubricant source.

[0005] The supply of lubricant to a bearing via a groove as previously mentioned is effective but it implies that the groove is open on the wall of the casing in the thickness of which it is arranged, to be able to recover by gravity the drops projected onto the wall above the groove by the movement of the differential crown in particular.

[0006] However, this opening of the throat can be a disadvantage if the vehicle has a significant angle of inclination, for example when being parked partially on a sidewalk for a long time. This angle of inclination modifies the direction gravity flow of lubricant within the groove so that the lubricant can flow out of the groove without supplying the bearing, potentially creating lubricant supply deficiencies which impair the proper operation of the gearbox.

[0007] The present invention makes it possible to overcome this problem by proposing a system for supplying lubricant to a bearing of a gearbox of a motor vehicle, comprising a wall configured to partially define a casing of said gearbox, a lubricant distributor and a groove formed in a thickness of the wall and configured to collect lubricant and guide it towards the bearing, the wall being inscribed in a plane defined by a longitudinal direction and a vertical direction perpendicular to the longitudinal direction, the groove extending mainly in the longitudinal direction, characterized in that the supply system comprises a lubricant guide device which is positioned at least partly opposite the groove and which is configured to partially close the groove.

[0008] The wall of the feed system, within which the groove is formed, corresponds to a part of a wall of the gearbox housing, the housing being configured to house a plurality of shafts, toothed wheels and bearings forming the gearbox.

[0009] The groove is formed within this wall of the supply system and is configured to guide lubricant to a bearing of the gearbox. The groove is oriented and inclined so that the lubricant therein flows in the longitudinal direction towards said bearing. The groove is oriented so that the longitudinal direction which defines it is secant with respect to the road, so that the gravitational force can act on the lubricant in the groove and drive it towards the bearing, at least when the vehicle is moving or stopped on a substantially horizontal roadway.

[0010] The lubricant distributor is configured to supply lubricant into the groove. Lubricant from the lubricant distributor flows within the groove from one longitudinal end to the opposite longitudinal end, until it reaches the bearing.

[0011] The wall of the feed system can receive projections of lubricant generated by the rotation of a differential crown of the gearbox and the drops of lubricant which impinge on the wall above the groove can then flow to the groove, mainly in the vertical direction, and penetrate into the groove, for example by capillarity, to participate in forming the flow of lubricant directed towards the bearing. For this purpose, the groove is open on an internal face of the wall of the feed system, that is to say a face facing the inside of the casing.

[0012] The lubricant supply for the bearing can, for example, be formed up to 30% by drops of lubricant collected along the wall and up to 70% by the lubricant directly from the lubricant dispenser.

[0013] In order to maintain this distribution, which makes it possible to reuse lubricant already present in the casing and thus limit the supply of new lubricant from the distributor, the supply system is equipped with a guide device which completes the shape of the groove. It is notable according to the invention that the groove has a conventional shape, open on the internal face of a wall of the casing, and that the supply, guidance and retention of the lubricant within this conventional groove is made possible by the presence of a guide device provided for this purpose. The guide device is a part separate from the wall of the casing which completes the shape of the groove to partially close it. The partial closure has the effect of retaining the lubricant within it, and the resulting partial opening has the effect of allowing drops of lubricant to enter the groove.

[0014] In other words, thanks to the guide device, the supply system according to the invention ensures distribution of the lubricant towards the bearing, whatever the origin of the lubricant, without the risk of seeing this lubricant flow out of the groove when the vehicle has a particular inclination, said guide device having the function of keeping the lubricant within the groove due to the closure of the groove that it generates.

[0015] It is understood that the guide device is advantageous in that it only achieves a partial closure of the groove, which also allows drops flowing along the wall in which the groove is formed to penetrate into this groove to increase the flow of lubricant towards the bearing.

[0016] According to an optional feature of the invention, the guide device comprises a main body extending at least partially along the groove parallel to the wall and a ramp extending at least transversely towards the groove from the main body.

[0017] The main body of the guide device extends opposite the wall and at least partially opposite the groove, and in particular provides the mechanical link between the guide device and the wall. The main body also carries the ramp. The guide device is particular in that the ramp allows contact with the inside of the groove or with an edge delimiting the groove, so as to retain the lubricant likely to escape from the groove and in that the main body, which supports this ramp, is opposite the wall of the supply system without completely closing the groove.

[0018] The main body extends mainly in the longitudinal direction so that the ramp it supports can have an orientation identical to the main dimension of the groove, the objective being to retain and guide the lubricant preferentially along the entire length of the groove so that it can circulate to the bearing.

[0019] The ramp has a longitudinal dimension equal to or substantially less than the longitudinal dimension of the main body, in order to participate in guiding the lubricant advantageously along the entire length of the groove.

[0020] The ramp also has a transverse dimension in order to extend towards the groove. It is therefore the ramp that allows the lubricant to be retained, which risks flowing out of the groove. The ramp is mechanically held by the main body within the groove and thus allows the lubricant to be guided along the groove to the bearing.

[0021] According to an optional characteristic of the invention, the main body and the ramp form a single-piece assembly, which can for example be obtained by molding.

[0022] According to an optional feature of the invention, the ramp is attached to the main body. The ramp can, for example, be fixed to the main body by gluing.

[0023] According to an optional feature of the invention, the main body comprises fixing means ensuring a mechanical connection with the wall. The main body can for example be fixed to the wall by screwing or riveting. Advantageously, the main body is fixed to the wall at a portion at which no lubricant likely to penetrate into the groove flows so as not to slow down or stop said flow. Considering the gearbox mounted on the vehicle, the main body is fixed to the wall under the groove, that is to say between the groove and the ground on which the vehicle rests, so that the drops of lubricant projected above the wall by the differential crown and likely to flow by gravity towards the groove are not brought into contact with the fixing means of the main body.

[0024] According to an optional feature of the invention, the ramp has a curved shape with a center of curvature of this curved shape which is arranged on the side of the wall of the supply system. In other words, the ramp has a concave shape seen from the wall of the supply system. The ramp thus curved forms a gutter making it possible to retain and guide the lubricant along the longitudinal dimension. The curved shape makes it possible in particular, by playing on the flexibility of the ramp, to adjust the vertical position of the line or surface of contact between the ramp and the surface or edge delimiting the groove and against which the ramp is in contact to partially close this groove. This ensures the sealing of the contact of the guide device along the groove.

[0025] According to an optional feature of the invention, the ramp comprises a free edge extending into the groove, the free edge bearing on a defined surface of the groove. The free edge corresponds to a portion of the ramp opposite a junction zone of the ramp on the main body. The ramp extends until it enters the groove with at least the free edge which is in contact with a surface defining the groove. to prevent lubricant from leaking between the groove and the ramp.

[0026] The free edge rests on the defined surface, preferably over the entire longitudinal dimension of the ramp. By defined surface of the groove, which can also be called lower surface, is meant the surface which is intended to be closest to the ground on which the vehicle equipped with the gearbox rests. More specifically, this defined surface, or lower surface, is the surface of the groove on which the lubricant mainly flows when it is guided to the bearing by the groove, due to the gravitational attraction exerted on the lubricant.

[0027] According to an optional feature of the invention, the ramp comprises a base connected to the main body, the free edge and the base being offset from each other in the vertical direction V, the base approaching a surface of the groove which is opposite the defined surface of the groove in contact with which the free edge is located.

[0028] In other words, the ramp comprises a base linked to the main body and a docking portion of which one end edge forms the free edge, the free edge being offset in the vertical direction relative to the base, said base being closer to an upper edge of the groove than to an opposite lower edge of said groove, while the free edge is in contact with this lower edge of the groove or a surface delimiting the groove and carrying this lower edge.

[0029] The base corresponds to the portion of the ramp mechanically linked to the main body. The vertical offset referred to here implies that the base is a higher area of ​​the ramp, if we consider the vertical direction, that is to say further from the road on which the vehicle equipped with the gearbox rests, than the free edge. In other words, the ramp is configured so that the gravitational force tends to direct the drops of lubricant in a direction going from the base towards the free edge and not the other way around.

[0030] According to an optional feature of the invention, the main body of the guide device has an offset in a transverse direction relative to the wall, the transverse direction being perpendicular to the longitudinal direction and to the vertical direction. The transverse direction corresponds to the direction perpendicular to the wall. The main body is therefore not arranged in contact with the wall except for the fixing zone of the main body, but at a distance corresponding to said offset in the transverse direction. In order to compensate for this transverse offset, the wall may comprise protrusions projecting from the wall in this same transverse direction so that the fixing means of the main body can interact with these protrusions. It is thus possible to fix the guide device to the wall while generating the offset in the transverse direction of the main body.

[0031] The transverse offset allows a passage to be formed between the main body and the edge of the wall delimiting the groove opposite the surface of the groove against which the ramp is supported. This passage allows the flow of the lubricant projected onto the wall to the groove. As mentioned, the guide device only partially closes the groove to preserve the collection of the lubricant projected onto the wall and flowing in the vertical direction to the groove.

[0032] According to an optional feature of the invention, the ramp comprises a longitudinal end provided with a guide member, the guide member being configured to guide the lubricant towards a bottom surface of the groove. The guide member makes it possible to ensure that the lubricant remains in the groove, in particular in the event of a particular inclination of the vehicle. The longitudinal end concerned corresponds to the end of the ramp closest to the bearing, that is to say the longitudinal end towards which the lubricant tends to flow. The guide member makes it possible to prevent part of the lubricant flowing along the ramp and arriving at the longitudinal end close to the bearing from falling from the ramp outside the groove.

[0033] According to an optional feature of the invention, the guide member is inclined relative to a transverse direction perpendicular to the longitudinal direction and to the vertical direction. The inclination of the guide member promotes the flow of the lubricant to the bottom of the groove while preventing this lubricant from being blocked by a guide member parallel to the transverse direction and therefore perpendicular to the direction of flow of the lubricant. The inclination of the guide member is such that, from the base of the ramp to the free edge of the ramp, the ramp is widened in the direction of flow of the lubricant.

[0034] The longitudinal end is also inclined relative to the transverse direction. In other words, the free edge of the ramp has a longitudinal dimension greater than a longitudinal dimension of the base of the ramp.

[0035] According to an optional feature of the invention, the ramp is made of flexible material. The flexible material allows the ramp to be flexible, in particular when the guide device is fixed to the wall, the ramp then being able to be constrained to ensure that once the guide device is fixed, it remains in contact with a surface defining the groove or an edge of this groove to ensure that the drops leaving the groove are collected by the ramp. The flexibility of the ramp thus allows adaptation of the guide device, which is advantageously an added part which does not involve modifications to the structure of the groove, to the manufacturing clearances of the casing and the wall in which the groove is inscribed.

[0036] The invention also covers a gearbox for a motor vehicle comprising a casing, at least one drive shaft bearing, a differential crown wheel and a system for supplying lubricant to the bearing, the supply system being as described previously.

[0037] The casing contains the various shafts and gears of the gearbox, and it is therefore at the level of an internal face of one of the walls of the casing that the groove is formed. The drive shaft bearing is the bearing to be supplied with lubricant. The supply system is therefore arranged so that the groove extends to an access to said drive shaft bearing.

[0038] As mentioned above, the differential crown, which is also connected to an axle of the vehicle, can project drops of lubricant into the housing due to the centrifugal force generated by the rotation of said differential crown. Drops of lubricant thus projected can be deposited on the wall of the supply system, above the groove, i.e. on a portion of the wall which extends vertically from the upper edge of the groove. The drops of lubricant can flow along this wall by gravity towards the groove.The shape of the guide device associated with the groove, which allows the groove to be closed only partially and to leave access to the groove, in particular on the side of the upper edge of the groove, allows these drops of lubricant to penetrate into the groove, either by capillarity or by detaching from the wall at the point where the groove is formed and falling into the guide device which brings the lubricant back into the groove. The guide device ensures that the lubricant coming from the distributor is fully guided towards the bearing to be lubricated, whatever the inclination of the vehicle equipped with the gearbox, and that additional lubricant can enter the groove to form a supplementary supply.

[0039] Other characteristics and advantages of the invention will become apparent from the following description on the one hand, and from several examples of embodiment given for informational and non-limiting purposes with reference to the attached schematic drawings on the other hand, in which:

[0040] [Fig-1] is a general view of a power supply system according to the invention,

[0041] [Fig.2] is a first three-quarter view of a feed system guidance device,

[0042] [Fig.3] is a second three-quarter view of the guidance device, showing a face of the guidance device opposite that seen in [Fig.2],

[0043] [Fig.4] is a first sectional view of the feed system, the section being made according to view II illustrated in [Fig.l],

[0044] [Fig.5] is a second sectional view of the feed system, the section being made according to view II-II illustrated in [Fig.5].

[0045] The LVT trihedron will represent the orientation of the figures. The longitudinal direction L and the vertical direction V correspond to two axes defining a main elongation plane of a wall of the casing, and the transverse direction T corresponds to an axis perpendicular to the longitudinal direction L.

[0046] [Fig. 1] is a general view of a lubricant supply system 1 according to the invention. The supply system 1 is integrated within a gearbox of a vehicle, for example a hybrid vehicle. The gearbox, not shown here as a whole, comprises a gearbox housing 2 within which are arranged several drive shafts mounted for rotation on bearings 4 and several toothed wheels respectively arranged on these shafts, all of these elements requiring regular lubrication using a lubricant such as oil.

[0047] In order to ensure a supply of lubricant, the supply system 1 according to the invention ensures the circulation of lubricant to one or more of the bearings 4 of the gearbox. The supply system 1 comprises for this purpose a wall 6 which forms a part of the gearbox casing 2, and a groove 8 formed in a thickness of said wall 6 and configured to ensure the circulation of the lubricant to the bearing 4, the groove not being visible in [Fig.l] because hidden by the guide device 16 which will be described below.

[0048] The supply system 1 also comprises a lubricant distributor 10, shown schematically in [Fig. 1] and capable of allowing circulation of lubricant in the groove 8 if the quantity of lubricant flowing within the groove is not sufficient. The groove 8 thus ensures a fluid connection between the lubricant distributor 10 and the bearing 4 to be lubricated.

[0049] The wall 6 extends mainly along a plane defined by a longitudinal direction L and a vertical direction V. The groove 8 is formed in the thickness of the wall 6, that is to say in a transverse direction perpendicular to the longitudinal and vertical directions. It also has a main elongation direction which is here parallel to the longitudinal direction L. In other words, the lubricant flowing in the groove 8 circulates mainly in the longitudinal direction L.

[0050] It should be noted that the longitudinal direction L is here inclined relative to the road on which the vehicle is traveling or stopped, so that the groove 8 is always oriented to form a path for the lubricant from the lubricant distributor 10 to the bearing 4. Such an inclination ensures the circulation of the lubricant within the groove 8 and up to the bearing 4 thanks to the force of gravity.

[0051] The gearbox also includes a differential crown, not visible here and connected to a vehicle axle to distribute the rotation speeds appropriately, the rotation of which, due to its large size and rotation speed, generates a projection of lubricant within the casing. The projection is random but allows the entire volume of the casing to be covered, and therefore all the drive shafts and toothed wheels.

[0052] A portion of this lubricant is projected against the wall 6 of the supply system 1. The wall 6 extending in particular in the vertical direction V, the portion of the lubricant which is projected against the wall 6 above the groove 8 therefore flows in this same vertical direction V thanks to the force of gravity, until it meets the groove 8. In this, this part of the lubricant can join the lubricant coming from the lubricant distributor 10 and the whole thing flows along the groove 8 in the longitudinal direction L.

[0053] In order to be able to collect the lubricant projected onto the wall 6 by the differential crown, the groove 8 opens onto the internal face of the wall facing the inside of the casing. It is thus possible to define an upper edge 12 and a lower edge 14 of the groove 8, these edges being respectively the edges at the junction between the groove 8 and the internal face of the wall 6. And the groove 8 forms an opening between the upper edge 12 and the lower edge 14, it being understood that the upper edge 12 is above the lower edge 14 considering the direction of gravity in the vertical direction. The opening of the groove 8 is necessary to recover, at the level of the upper edge 12 of the groove, the part of the lubricant extending over the part of the wall 6 arranged above the groove 8.As mentioned, the opening of the groove 8 is, however, to be considered a disadvantage when the vehicle is inclined in the transverse direction T, for example when partially parked on a sidewalk. The change in orientation of the gravitational force relative to the groove can cause the lubricant to flow out of the groove beyond the lower edge.

[0054] To prevent this flow of lubricant out of the groove, the supply system 1 according to the invention comprises a guide device 16 which partially closes the groove 8, thus preventing the lubricant from flowing out of it.

[0055] The guide device 16 comprises a main body 18 which in particular provides a mechanical connection with the wall 6, and a ramp 20 which extends at least transversely, that is to say in the transverse direction T, in the direction of the groove 8 and from the main body 18. The ramp 20 thus makes it possible, even if the vehicle is inclined in the transverse direction T, to retain the lubricant and / or to keep it within the groove 8 and to guide it to the bearing 4.

[0056] The main body 18 and the ramp 20 both extend in particular in the longitudinal direction L, preferably at least partially opposite the groove 8, so that the ramp 20 can extend in the direction of the groove 8 to penetrate it and so that the guide device 16 can partially close the groove 8.

[0057] The main body 18 further comprises fixing means 22 ensuring the mechanical connection with the wall. The fixing means may comprise a screw which is screwed into the thickness of the wall 6.

[0058] Preferably, the fixing means 22 are arranged under the groove 8, that is to say on the side of the lower edge 14 of the groove 8, so that the projection of the lubricant against the wall 6 as well as the flow of the lubricant projected along the wall to the groove 8 is not stopped or slowed down by the main body 18 of the guide device 16.

[0059] Figures 2 and 3 allow the structural and functional characteristics of the guide device to be detailed, [Fig.2] illustrating a first three-quarter view making visible a first face 24 of the guide device visible in [Fig.1], while [Fig.3] illustrates a second three-quarter view making visible a second face 26 of the guide device intended to be opposite the groove of the feed system.

[0060] [Fig. 2] makes more particularly visible the shape of the main body 18 of the guide device 16. The main body 18 has an arch shape with a longitudinal upright 28 which is intended to be substantially parallel to the longitudinal direction of the groove 8 when the guide device 16 is fixed. The main body 18 further comprises lateral tabs 30 between which said longitudinal upright 28 extends. The lateral tabs 30 extend vertically between a first fixing end 32 and a second connecting end 34 connected to the longitudinal upright 28.

[0061] The fixing means 22 may for example comprise orifices formed in the lateral tabs 30, at the first fixing end. The orifices may be crossed for example by a screw, and said screw is then screwed into the thickness of the wall to hold the guide device opposite the wall. Advantageously, the main body 18 comprises a fixing means 22 at each longitudinal end in order to reinforce the stability of the mechanical connection with the wall.

[0062] The orifices are defined by a peripheral edge which may have a circular shape or an oblong shape, in particular configured to allow an adjustment of the vertical position of the guide device relative to the wall, and more particularly an adjustment of the vertical position of the free end of the ramp relative to the groove. For example, the orifices have a diameter larger than that of the screw and larger than that of the tapped bore associated with the wall 6. The guide device 16 is prepositioned with each of the screws engaged in the tapped bore, and the screws are finally tightened when the vertical position of the guide device 16 is adapted so that the ramp 20 is slightly constrained against an edge or a surface delimiting the groove 8.

[0063] [Fig. 3] allows for a better description of the ramp 20 of the guide device 16. This ramp 20 forms an extension of the longitudinal upright 28, and here also of one of the lateral legs 30, namely the lateral leg which is intended to be closest to bearing 4 to be lubricated.

[0064] The ramp 20 comprises in particular a base 36, which corresponds to a portion of the ramp mechanically linked to the main body 18, and a docking portion 38, which is intended to interact with the groove 8, whether at the edge of the groove with the lower edge 14 thereof or inside the groove 8 with a surface of the groove carrying this lower edge. The docking portion 38 comprises a free edge 40, which corresponds to a portion of the ramp opposite the base 36.

[0065] The ramp 20 has a curved shape which allows the base 36 to extend outside the groove, at a distance from the wall 6 of the feed system 1, and the free edge 40 of the docking portion 38 to be in the groove 8 or in contact with an edge thereof to participate in partially closing the groove. The ramp 20 thus has a curved portion 42, interposed between the base 36 and the docking portion 38, which participates in giving this curved shape to the ramp. The direction of the curvature of the ramp 20, with a center of curvature which is on the side of the wall, generates a gutter shape open towards the groove 8.

[0066] The curved portion 42 may be original, so that the ramp 20 has a curved shape at rest, or else be formed by elastic deformation of the ramp 20, so that the curved shape of the ramp is generated by forcing the docking portion 38 of the ramp 20 against a surface delimiting the groove 8, this position then being fixed by the implementation of the fixing means 22.

[0067] The free edge 40 is offset in the vertical direction V relative to the base 36, the latter being closer to the upper edge 12 of the groove 8 than to the lower edge 14 while the free edge 40 is in contact with this lower edge 14 or with a surface delimiting the groove and carrying this lower edge. In other words, considering the vertical direction, the base 36 is arranged at a higher height than the free edge 40, so that if lubricant, in particular drops projected by the rotation of the differential crown, flows onto the ramp, this lubricant flows towards the free edge 40 in order to join the groove 8.

[0068] As can be seen in [Fig. 3], but also in [Fig. 4] which illustrates an embodiment in which the ramp of the guide device is within the groove, the ramp 20 further comprises a longitudinal end 44 provided with a guide member 46 extending along said longitudinal end. Such a longitudinal end 44 corresponds to that closest to the bearing 4 once the guide device 16 is fixed to the wall 6. F' guide member 46 makes it possible to retain the lubricant which can flow in the longitudinal direction F out of the groove and out of the bearing. F' guide member 46 corresponds to a rim ensuring the retention of the lubricant.

[0069] F' guide member 46 and the longitudinal end 44 are further inclined by relative to the transverse direction T, towards the bearing 4 to be lubricated. Such an inclination improves the guidance of the lubricant, as will be described in detail later.

[0070] The main body 18 and the ramp 20 may be a single-piece assembly, for example by being manufactured by molding. It is also possible for the main body and the ramp to be two separate entities and for the ramp to be subsequently attached to the main body, for example by gluing.

[0071] [Fig. 4] is a sectional view of the feed system 1 according to the invention when the guide device 16 is fixed to the wall 6 and partially closes the groove 8.

[0072] As previously described, the groove 8 is formed in the thickness of the wall 6. As a result, the groove 8 is in particular delimited by a lower surface 48, which opens onto the wall 6 by forming said lower edge 14, by an upper surface 50, visible in [Fig. 5] and which opens onto the wall 6 by forming said upper edge 12, and by a bottom surface 52. The bottom surface 52 is parallel to the wall 6, and is therefore defined by the longitudinal direction L and by the vertical direction. The lower and upper surfaces 48, 50 are parallel to each other, being perpendicular to the wall, and they are here defined by the longitudinal direction L and by the transverse direction T.

[0073] The lower surface 48, due to the force of gravity, is the surface along which the lubricant flows mainly in the longitudinal direction L. It is also from this lower surface 48 that the lubricant can flow out of the groove 8 in the absence of the guide device 16.

[0074] In order to prevent any leakage of lubricant, the free edge 40 of the ramp 20 is in contact with the lower surface of the groove. Advantageously, the contact surface between the ramp 20 and the lower surface 48 is as large as possible along the longitudinal direction so that the ramp can ensure that the lubricant remains in the groove over the largest possible longitudinal dimension.

[0075] As mentioned previously, the ramp 20 has a curved shape when the free edge 40, and where appropriate the docking surface 38, is in abutment on the lower surface 48 of the groove 8, with the base 36 which extends vertically at a distance from this lower surface 48 of the groove 8. As a result, at least a part of the ramp, and in particular the curved portion 42, is inclined relative to the lower surface 48 and makes it possible to guide the lubricant caused to flow along the ramp towards the bottom surface of the groove.

[0076] [Fig. 4] shows that the guide member 46 arranged at a longitudinal end 44 of the ramp 20 is inclined longitudinally so as to guide the lubricant towards a deflector 54 associated with the bearing 4. The deflector 54 makes it possible to guide the lu- grinding within the bearing, in order to distribute the lubricant more efficiently along the drive shaft intended to be carried by this bearing. The inclination of the guide member 46 prevents the lubricant from blocking at the ramp.

[0077] [Fig. 5] is a second sectional view of the feed system along the vertical direction V and the transverse direction T. [Fig. 5] illustrates the fact that the guide device 16 only partially closes the groove 8. Indeed, the ramp 20 is inserted into the groove 8 while being in contact with a surface, here the lower surface 48, of this groove, and the main body 18 of the guide device 16 has an offset along the transverse direction T relative to the wall 6. Such an offset makes it possible to free a transverse space 56 between the main body 18 and the upper edge 12 of the groove, that is to say the junction edge of the wall 6 with the upper surface 50 of the groove 8 which extends opposite the free edge 40 of the ramp 20, which allows the drops of lubricant flowing along the wall towards the upper edge of the groove to penetrate into the groove.The drops of lubricant enter the groove either by capillarity by following the wall 6 then the upper surface 50 of the groove 8 to then flow into the groove towards the bearing, or they detach from the wall at the level of the upper edge 12 of the groove 8 and are advantageously recovered by the ramp 20. The guiding device 16 thus has the function of guiding the lubricant and recovering any drops which could be lost.

[0078] [Fig.5] also illustrates at least one protrusion 58 at the level of the wall 6 projecting in the transverse direction T, the fixing means 22 of the main body 18 of the guide device 16 being able to interact with these protrusions 58. The protrusions make it possible to maintain the offset in the transverse direction T between the main body of the guide device and the wall.

[0079] The invention, as just described, achieves the aim it set itself, and makes it possible to propose a device for supplying lubricant to a bearing in a gearbox via a groove which is effective both in ensuring that lubricant cannot escape from the groove when the vehicle equipped with such a gearbox is inclined in an unusual manner relative to the road, and in ensuring that drops of lubricant dispersed in the gearbox housing can be collected in the groove. Variants not described here could be implemented without departing from the context of the invention, since, in accordance with the invention, they comprise a guide device associated with the groove which makes it possible to partially close this groove in order to both retain the lubricant already present within the groove and to collect an additional portion of lubricant.

Claims

Claims

1. A system (1) for supplying lubricant to a bearing of a gearbox of a motor vehicle, comprising a wall (6) configured to partially define a casing (2) of said gearbox, a lubricant distributor (10) and a groove (8) formed in a thickness of the wall (6) and configured to collect lubricant and guide it towards the bearing (4), the wall (6) lying in a plane defined by a longitudinal direction (L) and a vertical direction (V) perpendicular to the longitudinal direction (L), the groove (8) extending mainly in the longitudinal direction (L), characterized in that the supply system (1) comprises a lubricant guide device (16) which is positioned at least partly opposite the groove (8) and which is configured to partially close the groove (8).

2. A feed system (1) according to claim 1, wherein the guide device (16) comprises a main body (18) extending at least partially along the groove (8) parallel to the wall (6) and a ramp (20) extending at least transversely towards the groove (8) from the main body (18).

3. Feeding system (1) according to the preceding claim, in which the main body (18) comprises fixing means (22) ensuring a mechanical connection with the wall (6).

4. Feeding system (1) according to claim 2 or 3, wherein the ramp (20) has a curved shape with a center of curvature of this curved shape which is arranged on the side of the wall (6) of the feeding system.

5. A feed system (1) according to any one of claims 2 to 4, wherein the ramp (20) comprises a free edge (40) extending into the groove (8), the free edge (40) bearing on a defined surface (48) of the groove.

6. Feeding system (1) according to the preceding claim, wherein the ramp (20) comprises a base (36) connected to the main body (18), the free edge (40) and the base (36) being offset from each other in the vertical direction V, the base (36) approaching a surface (50) of the groove which is opposite the defined surface (48) of the groove in contact with which the free edge (40) is located.

7. A feed system (1) according to any one of claims 2 to 6, wherein the main body (18) of the guide device (16) has an offset in a transverse direction (T) relative to the wall (6), the transverse direction (T) being perpendicular to the longitudinal direction (L) and to the vertical direction (V).

8. A feed system (1) according to any one of claims 2 to 7, wherein the ramp (20) comprises a longitudinal end (44) provided with a guide member (46), the guide member (46) being configured to guide the lubricant towards a bottom surface (52) of the groove (8).

9. Feeding system (1) according to the preceding claim, wherein the guide member (46) is inclined relative to a transverse direction (T) perpendicular to the longitudinal direction (L) and to the vertical direction (V).

10. A feed system (1) according to any one of claims 2 to 9, wherein the ramp (20) is made of flexible material.

11. Gearbox for a motor vehicle, comprising a casing (2), at least one drive shaft bearing (4), a differential crown wheel and a system (1) for supplying lubricant to the bearing, the supply system being according to any one of the preceding claims.

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