LUBRICATION DEVICE for SPEED REDUCER or GEARBOX

Abstract

The invention relates to a lubrication device (40) for a speed reducer comprising: - a collector (50) for receiving and distributing lubricant comprising at least one bottom (51a) and an outer periphery (58); - a first toothed wheel (11) rotatable about a first axis of rotation (X); in which the collector (50) comprises a central opening (53) within which the first toothed wheel (11) is partially inserted so as to be able to project lubricant from the teeth towards the container of the collector. (Fig. 1)

Description

Title of the invention: LUBRICATION DEVICE for SPEED REDUCER or GEARBOX Technical field of the invention

[0001] The invention relates, in general, to the technical field of speed reducers, in particular their lubrication means. State of the prior art

[0002] To lubricate a speed reduction device, in particular bearings, gears, etc., the reducers may be equipped with a pump that circulates a lubricant such as oil in a lubrication circuit configured to reach different specific areas to be lubricated. These reducer lubrication devices are called "active". Such a device is for example described in document FR2982003, in which a pump supplies oil to a gearbox via a chute acting as a reservoir within the gearbox housing. The chute supplies oil to the rotating shafts of the gearbox via a plurality of orifices.This device has the disadvantage of consuming energy to operate the pump and taking up space on a vertical axis given that the only reservoir in the chute is located above the shafts, in particular between a secondary shaft and the upper wall of the casing.

[0003] There are also so-called "passive" lubrication devices, i.e. without a pump, in which ramps are formed within the casing to encourage the lubricant to rise from the bottom of the reducer to the top and thus disperse the lubricant in different areas of the reducer.

[0004] These passive lubrication solutions are not, however, entirely satisfactory and the rise of lubricant from the bottom to the top of the reducer is sometimes not sufficient, in particular when elements of the reduction device, for example a transmission shaft carrying toothed wheels, obstruct the rise of the lubricant to the top of the reducer. Statement of the invention

[0005] The invention aims to remedy this problem by proposing a lubrication device for a speed reducer comprising:

[0006] - a lubricant receiving and distribution manifold comprising at least one bottom and an outer rim;

[0007] - a first toothed wheel movable in rotation around a first axis of rotation X;

[0008] in which the collector has a central opening within which the first toothed wheel is partially inserted so as to be able to project lu- grinding from the teeth to the collector.

[0009] This lubrication device has the advantage of recovering and distributing a significant quantity of lubricant present within the speed reducer, while retaining the principle of passive lubrication. The collector acts as a container and occupies a central position within the speed reducer, which allows it to receive all the projections of lubricant coming from the first toothed wheel but also from other toothed wheels also present within the speed reducer. The lubricant can fall directly or indirectly back into the collector.

[0010] Preferably, the outer periphery of the first toothed wheel may extend radially beyond the bottom of the collector.

[0011] Advantageously, the outer periphery of the first toothed wheel can extend radially beyond the inner periphery of the central opening. Thus, the first toothed wheel is inserted into the central opening and passes right through the collector. This facilitates the recovery of the lubricant.

[0012] Preferably, the inner periphery of the central opening may comprise a portion of cylindrical surface concentric with the first axis of rotation. Thus, the lubricant is guided and directed from the teeth of the first toothed wheel to the central opening.

[0013] The lubrication device according to the invention may have one or other of the characteristics described below combined with each other or taken independently of each other:

[0014] - The inner perimeter of the central opening delimits the inner walls of the collector.

[0015] - the collector comprises a notch for the passage of a second toothed wheel mobile in rotation around the first axis of rotation.

[0016] - a first shaft coaxially carries a plurality of toothed wheels, the first gear wheel, the collector covering the outer periphery of at least one of the gear wheels.

[0017] According to another of its aspects, the invention relates to a speed reducer for a powertrain, comprising in an orthogonal reference frame XYZ:

[0018] - a lubrication device incorporating all or part of the characteristics of previously mentioned,

[0019] - a reduction device comprising a first shaft extending along the first axis of rotation and coaxially carrying the first toothed wheel,

[0020] - a hollow-shaped casing comprising a base and a peripheral wall extending from of material with the base, the peripheral wall partly surrounding the reduction device,

[0021] in which the lubricant receiving and distribution manifold is arranged in the casing between the peripheral wall and the first axis of rotation.

[0022] Thanks to this speed reducer architecture, it is possible to recover and distribute a significant quantity of lubricant present within the speed reducer, while retaining the principle of passive lubrication. In this case, the peripheral wall of the casing participates in the recovery of lubricant by being arranged close to the upper part of the collector, the lubricant falling by gravity into the collector container.

[0023] Advantageously, the collector may comprise a first reservoir and a second reservoir arranged on either side of the first toothed wheel and the central opening.

[0024] Preferably, the first reservoir and the second reservoir may be arranged on either side of a first geometric plane passing through the first axis of rotation and the second axis of the orthogonal reference frame perpendicular to the first axis of rotation, the first geometric plane passing through the peripheral wall of the casing in a direction substantially perpendicular thereto.

[0025] Advantageously, the first reservoir and the second reservoir may be connected by means of a first gutter conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity. Thus, it is possible to distribute the lubricant to different areas of the collector.

[0026] Preferably, the first reservoir and the second reservoir may be connected by means of a second gutter conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity, so that the first reservoir, the second reservoir, the first gutter and the second gutter form a common container capable of receiving the lubricant projected into the casing.

[0027] Advantageously, the first gutter and the second gutter may be axially spaced along the first axis of rotation and arranged on either side of the central opening to allow the lubricant projections from the teeth of the first toothed wheel to pass.

[0028] Preferably, at least the first reservoir may comprise a portion of cylindrical surface concentric with the first axis of rotation. Advantageously, the second reservoir may comprise a portion of cylindrical surface concentric with the first axis of rotation. According to an alternative, the first reservoir and the second reservoir may each comprise a portion of cylindrical surface concentric with the first axis of rotation. Thus, the lubricant is guided and directed from the teeth of the first toothed wheel to the collector.

[0029] In a complementary manner, a closing cover can be attached to the casing so as to form a closed enclosure around the reduction device, the collector being held in position partially by the casing and partially by the closing cover.

[0030] Advantageously, the reduction device may comprise a second shaft extending along a second axis of rotation and coaxially carrying a differential input wheel, the differential input wheel being partially immersed in lubricant, and a deflector disposed in the casing comprising a ramp capable of guiding the lubricant towards the first toothed wheel. The combination of the ramp and the collector comprising a central opening makes it possible to increase the quantity of lubricant recovered in the container.

[0031] Preferably, the ramp may comprise a cylindrical lubricant guide surface concentric with the differential input wheel and extending towards the first axis of rotation of the first toothed wheel. Thus, by approaching the first axis of rotation, it is possible to raise the ramp higher in the speed reducer despite the presence of a transmission shaft. This promotes the flow of lubricant towards the top of the speed reducer. With the deflectors known from the prior art in which the deflectors are formed in the mass of the casings, the location of the deflectors is limited and the flow of lubricant towards the top of the speed reducer is sometimes insufficient.

[0032] The speed reducer according to the invention may have one or other of the characteristics described below combined with each other or taken independently of each other:

[0033] - the first tank and the second tank are arranged on either side of a first geometric plane passing through the first axis of rotation and crossing the peripheral wall of the casing.

[0034] - the first tank and the second tank are arranged on either side of a first geometric plane passing through the first axis of rotation and the second axis of the orthogonal reference frame perpendicular to the first axis of rotation, the first geometric plane passing through the peripheral wall of the casing in a direction substantially perpendicular to it.

[0035] - the first tank comprises a first bottom and the second tank comprises a second bottom, the first bottom being axially offset along the second axis relative to the second bottom.

[0036] - the first toothed wheel rotates around the first axis of rotation in a direction preferred, the first reservoir facing the first gear wheel so as to receive the lubricant projected by the teeth. According to one example, the preferred direction of rotation of the first gear wheel is that which allows the motor vehicle to move forward.

[0037] - the deflector is manufactured in a separate part from the casing and in which the ramp includes a flow sector located at the end of the ramp and which is housed in the hollowed out side of the first cogwheel.

[0038] - the flow sector is arranged at least partly in a space in the form of right circular cylinder centered on the first axis of rotation and having a diameter equal to the outside diameter of the first bearing.

[0039] - the deflector is fixed relative to the casing.

[0040] - the deflector comprises a mounting portion comprising a plurality of elements fixing cooperating with complementary fixing elements arranged in the reducer housing.

[0041] - the first shaft coaxially carries a plurality of toothed wheels, and the sector flow is also arranged closer to the first axis of rotation than the radially outer periphery of the larger diameter gear wheel carried by the first shaft.

[0042] - the first gear wheel is arranged above the lubricant level, for example oil, especially above the nominal level NN.

[0043] The invention also relates to a powertrain comprising an electric machine and a speed reducer as described above. Where appropriate, the electric machine comprises a rotor shaft which may be coaxial and integral in rotation with the input shaft of the speed reducer.

[0044] Other characteristics and advantages of the invention are highlighted by the following description of non-limiting examples of embodiments of the different aspects of the invention. brief description of the figures

[0045] Other characteristics and advantages of the invention will emerge on reading the description which follows, with reference to the appended figures, which illustrate: [Fig.l]: a partial front view of a speed reducer according to a first embodiment, shown without the closing cover.

[0046] [Fig.2]: a top view of the speed reducer of [Fig.l].

[0047] [Fig.3]: a front view of a speed reducer, according to a second mode of rea lization, shown without the closing cover.

[0048] [Fig.4]: a detailed view showing the assembly of the deflector of the second mode of realization in the casing (without the differential input wheel).

[0049] [Fig.5]: a top view of the speed reducer according to the second mode of rea lization of [Fig.3].

[0050] [Fig.6]: an isometric view of the speed reducer collector according to the second embodiment of [Fig.3].

[0051] [Fig.7]: a partial front view of a speed reducer according to a third mode of realization. DETAILED description of an embodiment

[0052] Figures 1 and 2 show a speed reducer 1 for a motor vehicle according to a first embodiment of the invention. This speed reducer is generally integrated within a main powertrain of a vehicle, in particular an electric motor vehicle, or a secondary powertrain. For example, it may be a secondary electric powertrain of a hybrid vehicle, in particular intended for the rear axle of the vehicle.

[0053] The speed reducer 1 comprises, in particular in an orthogonal reference frame XYZ, a first shaft 110 extending along a first axis of rotation X and coaxially carrying a first toothed wheel 11 and a hollow-shaped casing 60 comprising a base 61 and a peripheral wall 62 made from the same material as the base. The peripheral wall 62 partly surrounds the first toothed wheel 11. In this example, the speed reducer comprises a single speed ratio.

[0054] In the orthogonal reference frame XYZ, the planes XY, YZ and XZ are perpendicular to each other.

[0055] In the following description, the first axis of rotation is called axis of rotation X, the second axis of rotation is called axis of rotation X2, and the third axis of rotation is called axis of rotation X3.

[0056] In the description and the claims, the terms "external" and "internal" as well as the "axial" and "radial" orientations will be used to designate, according to the definitions given in the description, elements of the transmission system. By convention, the "axial" orientation relates to the reference axes X, Y or Z or to directions parallel to these axes, and the "radial" orientation is directed orthogonally to the reference axes X, Y and Z. A "radially internal" element is located closer to the reference axis than a "radially external" element.

[0057] The first shaft mentioned previously as well as in the set of claims corresponds to the intermediate shaft 110 of the reduction device 10 which will be described below in the embodiments.

[0058] The terms "upper", "lower", "top", "bottom", and "bottom" should be considered when viewing the speed reducer in a position / tilt similar to its position when mounted on a horizontally parked vehicle.

[0059] [Fig. 1] is a simplified front view of a speed reducer 1 according to a first embodiment of the invention shown without its closing cover so as to view the interior of the speed reducer. [Fig. 2] partially shows the same speed reducer 1 in top view.

[0060] In [Fig.l], the reducer is shown in a position corresponding to its position when mounted in a vehicle parked on a horizontal plane. It has a relatively low part and a relatively high part.

[0061] The reduction device 10 generally comprises: - an input shaft 100 intended to be driven by a motor, in particular an electric machine, around a third axis of rotation X3, - a second shaft 120 extending along a second axis of rotation X2 and coaxially carrying a differential input wheel 30, as well as a differential bridge capable of rotating two half-shafts along a second axis of rotation X2, - an intermediate shaft 110 movable in rotation around the first axis of rotation X, and capable of transmitting a torque between the input shaft 100 and the differential input wheel 30.

[0062] The reduction device 10 is generally housed in a closed enclosure formed by the casing 60 and a closing cover 70 attached to the casing.

[0063] In order to improve the lubrication within the speed reducer 1, the latter notably comprises a lubrication device 40 comprising:

[0064] - a collector 50 for receiving and distributing lubricant comprising at least a 5la background and an outer perimeter 58;

[0065] - the first toothed wheel 11 movable in rotation around the first axis of rotation X;

[0066] in which the collector 50 has a central opening 53 within which the first toothed wheel 11 is partially inserted so as to be able to project lubricant from the teeth towards the collector. The inner periphery 53a of the central opening 53 delimits the inner walls of the collector.

[0067] According to this first embodiment, the shapes of the collector 50 follow as closely as possible the profile of the first toothed wheel 11. Thus, the inner periphery 53 of the central opening 53 comprises a portion of cylindrical surface 54a concentric with the first axis of rotation X. Also, as illustrated in [Fig.2], the inner periphery 53a has a rectangular shape in top view which surrounds the profile of the first toothed wheel.

[0068] The collector 50 for receiving and distributing lubricant is arranged in the casing 60 between the peripheral wall 62 and the first axis of rotation X. This collector 50 has the particularity of comprising a first reservoir 51 and a second reservoir 52 arranged on either side of the first toothed wheel. In particular, the first reservoir 51 and the second reservoir 52 are arranged on either side of a first geometric plane XY passing through the first axis of rotation X and the second axis Y of the orthogonal reference frame perpendicular to the first axis of rotation X, the first geometric plane XY passing through the peripheral wall 62 of the casing in a direction substantially perpendicular thereto. The collector 50 is held in position partially by the casing 60 and partially by the closing cover 70.

[0069] In order to make the speed reducer more compact, the peripheral wall 62 of the casing 60 comprises a cylindrical surface 63 coaxial with the axis of rotation X which partially surrounds the external periphery of the first toothed wheel. The second axis Y then defines a normal to the cylindrical surface 63.

[0070] [Fig. 1] illustrates the lubrication of this reduction device which is partially achieved by the projection of lubricant (represented by the black arrows), for example oil 80, conveyed by the first toothed wheel. The oil coming from the bottom of the reducer is raised upwards by means of the rotation of the first toothed wheel, then is projected towards the peripheral wall 62 and in the direction of the first reservoir 51. Given that the external periphery 11a of the first toothed wheel 11 extends radially beyond the external periphery 58 of the first reservoir and the second reservoir, the lubricant can easily fall back into the collector.

[0071] The first toothed wheel 11 rotates around the first axis of rotation X in a preferred direction. In this example, the preferred direction of rotation of the first toothed wheel is that which allows the motor vehicle to move forward. The first reservoir 51 facing the first toothed wheel 11 receives the lubricant projected by the teeth. Another portion of the lubricant also falls back into the second reservoir 52.

[0072] The first reservoir 51 comprises a first bottom 51a and the second reservoir 52 comprises a second bottom 52a, the first bottom being axially offset relative to the second bottom along the second axis Y of the orthogonal reference frame.

[0073] As illustrated in [Fig.2], the first reservoir 51 and the second reservoir 52 are connected by means of a first gutter 56 and a second gutter 57 conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity. Thus, it is possible to distribute the lubricant to different areas of the collector. In this example, the collector has an O shape. The two reservoirs 51, 52 extend parallel to the axis of rotation X. The collector 50 comprises a plurality of holes or conduits 59 allowing streams of lubricating oil to flow onto different areas of the speed reducer.

[0074] The casing 60 comprises on the internal face of the peripheral wall 62 two drip edges 69 located directly above the collector 50, the drip edge 69 taking the form of a protrusion of material. The drip edges 69 make it possible to recover more lubricant within the collector.

[0075] We will now describe with reference to Figures 3 to 6, a speed reducer 1 according to a second embodiment of the invention similar to the first embodiment in particular by the fact that the first reservoir 51 and the second reservoir 52 are connected by means of a second gutter 57 conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity. Thus, the first reservoir 51, the second reservoir 52, the first gutter 56 and the second gutter 57 form a common container capable of receiving the lubricant projected into the casing 60.

[0076] The speed reducer 1 according to this second embodiment has two speed ratios. It comprises in particular: - an input shaft 100 intended to be driven by a motor, in particular an electric machine, around a third axis of rotation X3, - a second shaft 120 extending along a second axis of rotation X2 and coaxially carrying a differential input wheel 30, as well as a differential bridge capable of rotating two half-shafts along a second axis of rotation X2, - an intermediate shaft 110 movable in rotation around the first axis of rotation X, and capable of transmitting a torque between the input shaft 100 and the differential input wheel 30.

[0077] The input shaft 100 is capable of being driven coaxially by an electric machine rotor shaft, in particular by means of splines.

[0078] The differential input wheel 30 drives the differential axle in a known manner to rotate about the axis of rotation Y. The differential input wheel 30 is the drive wheel of the differential drive device.

[0079] The axes of rotation X, X2 and X3 are parallel.

[0080] The speed reducer 1 comprises a first double reduction stage E1 between the input shaft 100 and the intermediate shaft 110 and a second reduction stage E2 between the intermediate shaft 110 and the differential input wheel 30.

[0081] The first double reduction stage El comprises: - on the one hand, for the first ratio, a first pinion 101 integral in rotation with the input shaft 100 relative to the axis of rotation Z as well as a second toothed wheel 12 meshing with the first pinion 101 and capable of driving the intermediate shaft 110 in rotation around the axis of rotation X; and - on the other hand, for the second gear, a second pinion 102 integral in rotation with the input shaft 100 relative to the axis of rotation Z as well as the first toothed wheel 11 meshing with the second pinion 102 and capable of driving the intermediate shaft 110 in rotation around the axis of rotation X.

[0082] The gear ratio change occurs at the first double reduction stage El by means of a gear selection device (not shown).

[0083] Thus, the first shaft 110 corresponding to the intermediate shaft coaxially carries a plurality of toothed wheels, the first toothed wheel 11, the second toothed wheel 12 and an output pinion 13 kinematically linked with the differential input wheel 30.

[0084] The reduction device 10, in particular the bearings supporting the shafts 100, 110, the meshing between the pinions 101, 102 and the toothed wheels 11, 12, the meshing between the output pinion 13 and the differential input wheel 30 as well as the dog clutch sleeve need to be lubricated, in particular with oil. The lubrication of the reducer is passive here. In other words, it does not include a pump dedicated to circulating a lubricant within the reducer. The lubrication is therefore based here on the presence of an oil bath at the bottom of the reducer and on a conveyance of this oil towards the various elements of the reducer to be lubricated (bearings, meshes, dog clutch teeth) thanks, in particular, to the projections of oil caused by the rotation of the differential input wheel 30, the pinions 101, 102, 13 and the toothed wheels 11, 12, and thanks to gravity.

[0085] When the vehicle is stationary, a lower portion of the differential input wheel 30 is immersed in the oil bath. When the vehicle is moving, the differential input wheel 30 rotates about the second axis of rotation X2, which makes it possible to disperse the oil, in particular to make it rise as indicated by the arrow F. The oil level at the bottom of the reducer is indicated by the mark NN.

[0086] To improve the passive lubrication of the reducer, a deflector 20 is arranged, in the lower part of the reducer, to promote the rise of the lubricant and a collector 50 is arranged in the upper part so as, on the one hand, to receive the lubricant which has been previously raised and, on the other hand, to redirect the lubricant to different points of the speed reducer, in particular by gravity. The deflector 20 makes it possible in particular to guide the projection of oil onto the first toothed wheel 11.

[0087] In this embodiment, the cooperation of the deflector 20 and the first toothed wheel 11 of the second gear is shown in [Fig.4].

[0088] The first toothed wheel 11 of the second gear comprises an annular groove 11b arranged around the axis of rotation X and axially open on one of the sides of the first toothed wheel 11.

[0089] The deflector 20 comprises a ramp 25 capable of guiding the lubricant. A portion of the ramp 25 is arranged inside the annular groove 11b of the first driven wheel 11. The ramp 25 is configured to direct the lubricant into the annular groove so that the lubricant is centrifuged by the toothed wheel and thus redirected towards the top of the speed reducer.

[0090] The ramp 25 comprises in particular a cylindrical lubricant guide surface which is concentric with the differential input wheel 30 and a flow sector 28 located at the end of the ramp 25 and which is housed in the hollowed-out flank 11b of the first toothed wheel 11.

[0091] The lower edge of the ramp 25 is preferably arranged below the oil level, in particular below the nominal level NN. The nominal level corresponds to the indicative oil level marked on the reducer, when the vehicle is stationary. Otherwise, the nominal level may correspond to the horizontal plane passing through the lower edge of the opening intended for filling / draining the reducer. The first toothed wheel 11 of the second gear is arranged completely above the nominal oil level.

[0092] The output pinion 13 of the intermediate shaft 110 is arranged beyond an upper end of the ramp 25 of the deflector 20.

[0093] The deflector 20 also comprises a mounting portion 26 extending substantially in a plane perpendicular to the axis of rotation X. The mounting portion 26 also comprises a plurality of fixing studs 29 cooperating with housings 63 arranged in the casing 60 of the reducer. The fixing studs 29 project from the mounting portion 26.

[0094] The reduction device 10 is generally housed in a closed enclosure formed by the casing 60 and a closing cover 70.

[0095] The casing 60 and a closing cover 70 are assembled to each other and enclose the reduction device 10. The casing 60 can also form all or part of the casing of the electrical machine.

[0096] In this second embodiment, the speed reducer 1 also comprises a collector 50 for receiving and distributing lubricant arranged in the casing 60 between the peripheral wall 62 and the first axis of rotation X. This collector 50 has the particularity of comprising a first reservoir 51 and a second reservoir 52 arranged on either side of the first toothed wheel.

[0097] As illustrated in Figures 4 and 5, the first reservoir 51 and the second reservoir 52 are connected by means of a first gutter 56 and a second gutter 57 conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity. Thus, it is possible to distribute the lubricant to different areas of the collector. In this collector 50, the first gutter 56 and the second gutter 57 are axially spaced along the first axis of rotation X and arranged on either side of a central opening 53 to allow the lubricant projections from the teeth of the first toothed wheel to pass through. In this example, the collector has an O shape. The two reservoirs 51, 52 extend parallel to the axis of rotation X. The collector 50 has a plurality of holes or conduits 59 allowing streams of lubricating oil to flow onto different areas of the speed reducer.

[0098] The collector 50 is held in position partially by the casing 60 and partially by the closing cover 70. The casing 60 thus comprises two mounting housings 63 cooperating with two fixing studs 59 of the collector and the closing cover 70 comprises two other mounting housings 63 cooperating with two other fixing studs 59 of the collector.

[0099] The peripheral wall 62 of the casing 60 participates in the recovery of lubricant by being arranged close to the upper part of the collector, the lubricant falling back by gravity into the collector. The collector occupies a central position within the speed reducer which allows it to receive all the projections of lubricant coming from the first toothed wheel but also from other toothed wheels also present within the speed reducer.

[0100] Advantageously, the collector 50 comprises a notch 55 for the passage of the second toothed wheel 12 movable in rotation about the first axis of rotation X. The notch ensures a partial passage of the second toothed wheel 12 between the two reservoirs 51, 52. It is then possible to recover lubricant projected by this second toothed wheel 12 as well. In this example, the first shaft 110 coaxially carries a plurality of toothed wheels, including the first toothed wheel 1 and the second toothed wheel 12, the collector 50 covering the external periphery of at least one of the toothed wheels. In the present case, the collector 50 covers the external periphery 11a of the first toothed wheel 12 via a cylindrical surface portion 54a. As illustrated in [Fig.6], the cylindrical surface portion 54a forms the bottom of the gutter 57.

[0101] This cylindrical surface portion 54a comprises a concave shape 81 located on top of the oil retention collector 50. A hole 82 is formed in the center of this concave area 81 in order to allow a stream of lubricating oil to flow onto a specific area of ​​the speed reducer.

[0102] We will now describe with reference to [Fig.7], a speed reducer 1 according to a third embodiment of the invention which is distinguished from the first embodiment by the fact that the collector 50 comprises a central opening 53 within which the first toothed wheel 11 is partially inserted so as to be able to project lubricant from the teeth towards the container of the collector and by the fact that the external periphery 11a of the first toothed wheel extends radially beyond the internal periphery 53a of the central opening.

[0103] In this third embodiment, the first reservoir 51 and the second reservoir 52 are connected by means of a first gutter 56 and a second gutter 57 conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity. Thus, it is possible to distribute the lubricant to different zones of the collector. In this collector 50, the first gutter 56 and the second gutter 57 are axially spaced along the first axis of rotation X and arranged on either side of a central opening 53 to allow the projections of lubricant from the teeth of the first toothed wheel 11 to pass. The collector 50 comprises a plurality of chutes 75 allowing streams of lubricating oil to flow onto different zones of the speed reducer.

[0104] The chute 75 comprises a bottom and two edges which guide the lubricant as close as possible to the area of ​​the reducer to be lubricated. The outlet of the chute 75 is located below the bottom of the collector reservoir.

[0105] Advantageously, the casing 60 comprises on the internal face of the peripheral wall 62 a drip edge 69 located directly above the collector 50, the drip edge 69 taking the form of a protrusion of material. In this example, the profile of the drip edge 69 is linear and oriented in the direction of demolding of the casing 60 obtained by casting. The drip edge 69 makes it possible to recover more lubricant within the collector 50. The lubricant which runs along the peripheral wall preferentially returns to the collector by following the shape of the drip edge rather than returning directly to the bottom of the speed reducer. The lubricant falls back into the collector by flowing drop by drop from the drip edge 69.

[0106] In the various embodiments described here, the deflector 20 allows oil to be brought up into a central zone of the reducer which is nevertheless cluttered by the intermediate shaft 110, the toothed wheels 11, 12 and the output pinion 13.

[0107] Naturally, the invention is described in the above by way of example. It is understood that those skilled in the art are able to carry out different variant embodiments of the invention without departing from the scope of the invention. For example, the invention which has been described here in the context of a single-ratio speed reducer can also be applied to a speed reducer with two speed ratios or even more than two ratios. The invention can also be applied to gearboxes.

[0108] It is emphasized that all features, as they emerge for a person skilled in the art from the present description, the drawings and the attached claims, even if they have been specifically described only in relation to other determined features, both individually and in any combinations, may be combined with other features or groups of features disclosed herein, provided that this has not been expressly excluded or that technical circumstances make such combinations impossible or devoid of sense.

Claims

Claims

1. Lubrication device (40) for a speed reducer comprising: - a collector (50) for receiving and distributing lubricant comprising at least one bottom (51a, 52a) and an outer periphery (58); - a first toothed wheel (11) movable in rotation about a first axis of rotation (X); in which the collector (50) comprises a central opening (53) within which the first toothed wheel (11) is partially inserted so as to be able to project lubricant from the teeth towards the collector.

2. A lubricating device (40) according to claim 1, wherein the outer periphery (11a) of the first gear wheel extends radially beyond the bottom (51a, 52a) of the collector.

3. A lubricating device (40) according to claim 1 or 2, wherein the outer periphery (11a) of the first gear wheel extends radially beyond the inner periphery (53a) of the central opening.

4. Lubrication device (40) according to the preceding claim, in which the inner periphery (53a) of the central opening (53) comprises a portion of cylindrical surface (54a, 54b) concentric with the first axis of rotation (X).

5. Lubrication device (40) according to one of the preceding claims, in which the collector (50) comprises a notch (55) for the passage of a second toothed wheel (12) movable in rotation around the first axis of rotation (X).

6. Lubrication device (40) according to one of the preceding claims, in which a first shaft (110) coaxially carries a plurality of toothed wheels (11, 12) including the first toothed wheel (11), the collector (50) covering the external periphery of at least one of the toothed wheels.

7. Speed reducer (1) for a powertrain, comprising in an orthogonal reference frame (XYZ): - the lubrication device (40) according to one of the preceding claims, - a reduction device (10) comprising a first shaft (110) extending along the first axis of rotation (X) and coaxially carrying the first toothed wheel (11), - a hollow-shaped casing (60) comprising a base (61) and a peripheral wall (62) made of the same material as the base, the peripheral wall partly surrounding the reduction device (10), in which the collector (50) for receiving and distributing lubricant is arranged in the casing (60) between the peripheral wall (62) and the first axis of rotation (X).

8. Speed reducer (1) according to the preceding claim, in which the collector (50) comprises a first reservoir (51) and a second reservoir (52) arranged on either side of the first toothed wheel and the central opening (53).

9. Speed reducer (1) according to claim 8, wherein at least the first reservoir (51) comprises a cylindrical surface portion (54a) concentric with the first axis of rotation (X).

10. Speed reducer (1) according to claim 8 or 9, in which the first reservoir (51) and the second reservoir (52) are arranged on either side of a first geometric plane (XY) passing through the first axis of rotation (X) and the second axis of the orthogonal reference frame (Y) perpendicular to the first axis of rotation, the first geometric plane (XY) passing through the peripheral wall of the casing in a direction substantially perpendicular thereto.

11. Speed reducer (1) according to one of claims 8 to 10, in which the first reservoir (51) and the second reservoir (52) are connected by means of a first gutter (56) conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity.

12. Speed reducer (1) according to claim 11, wherein the first reservoir (51) and the second reservoir (52) are connected by means of a second gutter (57) conveying the lubricant from the first reservoir to the second reservoir under the effect of gravity, so that the first reservoir, the second reservoir, the first gutter and the second gutter form a common container capable of receiving the lubricant projected into the casing (60).

13. Speed reducer (1) according to claim 12, in which the first gutter and the second gutter (56, 57) are axially spaced along the first axis of rotation (X) and arranged on either side of the central opening (53) to allow the lubricant projections from the teeth of the first toothed wheel to pass.

14. Speed reducer (1) according to one of claims 7 to 13, wherein the reduction device (10) comprises a second shaft (120) extending along a second axis of rotation (X2) and coaxially carrying a differential input wheel (30), the differential input wheel (30) being partially immersed in lubricant, and a deflector (20) arranged in the casing (60) comprising a ramp (25) capable of guiding the lubricant towards the first toothed wheel.

15. Speed reducer (1) according to the preceding claim, in which the ramp (25) comprises a cylindrical guide surface (27) of the lubricant concentric with the differential input wheel (30) and which extends in the direction of the first axis of rotation (X) of the first toothed wheel (H).