OIL SUPPLY DEVICE FOR A MECHANICAL REDUCTION GEAR ON AN AIRCRAFT TURBOMACHINE
The dual-groove oil supply device addresses integration and maintenance issues in aircraft turbomachine gearboxes by ensuring continuous lubrication, enhancing reliability and reducing wear through dual-groove and channel design for normal and degraded operations.
Patent Information
- Application Number
- FR2024001798
- Authority / Receiving Office
- FR · FR
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2024-02-23
- Publication Date
- 2026-01-30
- Estimated Expiration
- 2044-02-23
AI Technical Summary
Existing lubrication systems for aircraft turbomachine gearboxes, particularly epicyclic and differential reducers, are bulky, prone to wear, and difficult to integrate with flexible turbomachine structures, leading to maintenance challenges and potential damage to satellite bearings during oil supply interruptions.
An oil supply device with dual annular grooves and channels, where a first groove provides normal operation oil flow and a second groove with reduced flow rate ensures continuous lubrication during interruptions, using flow restrictors or smaller channels to maintain oil supply to satellite bearings.
The solution provides reliable, compact, and efficient lubrication compatible with flexible turbomachine structures, reducing wear and maintaining lubrication during oil supply disruptions, thus enhancing gearbox reliability and maintenance efficiency.
Smart Images
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Abstract
Description
Title of the invention: OIL SUPPLY DEVICE FOR A MECHANICAL REDUCER OF AN AIRCRAFT TURBO-MACHINE Technical field of the invention
[0001] The present invention relates to an oil supply device for a mechanical reducer of an aircraft turbomachine, as well as a mechanical reducer comprising such a device. Technical background
[0002] The role of a mechanical reducer is to modify the speed ratio and torque between the input shaft and the output shaft of a mechanism.
[0003] New generations of turbofan engines, particularly those with a high bypass ratio, include a mechanical gearbox to drive the shaft of a fan. Typically, the purpose of the gearbox is to transform the high rotational speed of the power turbine shaft into a slower rotational speed for the fan-driving shaft.
[0004] Such a reduction gear comprises a central pinion, called the sun gear, a ring gear, and pinions called planet gears, which mesh between the sun gear and the ring gear. The planet gears are held by a frame called a planet carrier. The sun gear, ring gear, and planet carrier are planetary gears because their axes of revolution coincide with the longitudinal axis of the turbomachine. The planet gears each have a different axis of revolution and are equally spaced on the same operating diameter around the axis of the planet gears. These axes are parallel to the longitudinal axis of the turbomachine.
[0005] Several gearbox architectures exist. In the state of the art of turbofan engines, gearboxes are of the planetary or epicyclic type. In other similar applications, there are so-called differential or compound architectures.
[0006] - On a planetary gearbox, the planet carrier is fixed and the ring gear constitutes the output shaft of the device which rotates in the opposite direction to the solar.
[0007] - On an epicyclic reducer, the ring gear is fixed and the planet carrier constitutes the output shaft of the device which rotates in the same direction as the solar panel.
[0008] - On a differential reducer, no element is fixed for rotation. The ring rotates in the opposite direction to the solar panel and the satellite carrier.
[0009] Reducers can be composed of one or more meshing stages. This meshing is achieved in various ways such as by contact, by friction or by magnetic fields.
[0010] There are several types of contact meshing, such as with straight teeth or chevron.
[0011] Epicyclic gear reducers, in particular, have the advantage of offering significant speed reduction ratios in compact sizes. However, like differential reducers, they have the disadvantage of having planetary gears that rotate around the axis of rotation of the reducer's drive shaft, which is coaxial with the planetary gear. They therefore require devices for transferring oil from a reservoir and pump located in a fixed frame of reference to lubrication means that follow the rotational movement of the planetary gear axes around the drive shaft. To solve this problem, commonly used devices include rotary joint systems.
[0012] These systems have the disadvantages of being quite bulky and experiencing wear that is not very compatible with the service life required for aircraft engines, which impacts engine maintenance. Finally, these gearboxes are difficult to integrate with a flexible turbomachine structure, recommended, for example, to compensate for the loss or breakage of a fan blade, or with a modular design to facilitate engine assembly.
[0013] In order to remedy these drawbacks, the applicant has already proposed, in applications WO-A1-2010 / 092263, FR-A1-2 987 416, WO-A1-2019 / 16463 and WO-A1-2019 / 16491, lubrication devices without rotating seals. These devices comprise oil jets that are connected to an oil circuit of the fixed reference frame and are designed to project oil into an annular groove of an oil supply device (called a "wheel" or "distributor") of the rotating reference frame. The oil supply device is rotationally fixed to the planet carrier and confines the oil projected by the jets, then directs it by centrifugal force to the lubrication means for the planet bearings, in particular.
[0014] These devices thus greatly improve the reliability of the gearbox lubrication system as well as its maintenance.
[0015] Furthermore, the technical solution described in application FR-A1-3 047 279 attempts to adjust the oil flow to different gears according to their lubrication requirements. To this end, the supply device comprises two annular grooves and axially offset nozzles that supply these grooves. These grooves supply different circuits and communicate with each other by overflow.
[0016] The technical solution described in application FR-A1-3 041 054 also attempts to adjust the oil flow to different lubrication points, such as gears, according to their lubrication requirements. To achieve this, the oil supply system is segmented into a circumferential series of basins arranged around the axis of rotation, and nozzles supply these sections. The oil recovered by each basin is then directed to a circuit dedicated to a particular lubrication station.
[0017] Among the gearbox components lubricated by the oil supply system are the planetary gear bearings. These bearings support the load exerted on the planetary gears. When the bearings are of the plain or hydrodynamic type, they must be supplied with a certain quantity of oil because without oil the bearings will not function correctly.
[0018] When the oil supply is interrupted, the pump does not draw oil from the oil reservoir, and the device is therefore no longer supplied with oil. The satellite bearings are then deprived of oil, which risks damaging them and causing premature wear of the gearbox. It is therefore necessary to continue supplying oil to the satellite bearings during periods when the device's oil supply is interrupted. It would indeed be beneficial for the satellite bearings to remain supplied with oil, even with a small amount, to maintain an oil film between the satellites and their bearings and prevent the satellites from rubbing against their bearings. This would prevent overheating, wear, or seizing due to friction, which would be dangerous for the gearbox's operation.
[0019] The invention makes it possible to meet this need in a simple, efficient and economical way. Summary of the invention
[0020] The invention relates to an oil supply device for a mechanical gearbox of an aircraft turbomachine, this device comprising a wheel which has a generally annular shape around an axis and which includes:
[0021] - a first annular groove opening radially inwards to the oil supply to the device by spraying oil into the throat,
[0022] - of the first internal channels extending at least partly radially with respect to to the axis and comprising radially internal ends connected to the first groove and radially external ends connected to oil supply ports of the reducer, these ports opening in an axial direction,
[0023] characterized in that it further comprises:
[0024] - a second annular groove opening radially inwards to the oil supply to the device by spraying oil into the groove, the first and second grooves being adjacent,
[0025] the second groove being connected to said ports or to said first channels or to said first groove by second channels which have a minimum oil passage cross-section less than a minimum oil passage cross-section of the first channels.
[0026] It is therefore understood that the two grooves of the wheel have the function of supplying in The first groove of the impeller is connected to the ports by primary channels designed to supply oil to the ports during normal operation and at a normal flow rate. This flow rate depends, in particular, on the minimum oil passage cross-section of these primary channels and the rotational speed of the device around its axis. The second groove of the impeller is connected to secondary channels designed to supply oil to the ports during degraded operation, for example, in the event of an oil supply interruption to the device. These secondary channels have a minimum oil passage cross-section that is smaller than that of the primary channels, so as to deliver oil at a lower flow rate, but which will continue to supply the ports with oil as long as there is oil remaining in the second groove.In normal operation, oil can also flow from the second groove to the second channels, but the flow rate provided by these second channels is not significant compared to that delivered by the first groove and the first channels. During an oil supply interruption, only the second groove and the second channels will deliver oil, albeit at a lower flow rate. According to the invention, the second channels can be connected to the first groove, the first channels, or directly to the ports.
[0027] second annular groove thus constitutes an additional oil reserve which empties less quickly than the first annular groove which constitutes a main oil reserve.
[0028] The proposed solution is compatible with single-stage or multi-stage gearboxes. It is also compatible with epicyclic or differential gearboxes. It is also compatible with spur, helical, or herringbone gears. Furthermore, it is compatible with all types of planet carriers, whether monobloc or cage-type.
[0029] The device according to the invention may comprise one or more of the following features, taken individually or in combination with each other: - the minimum oil passage cross-section of the second channels is defined by the second channels themselves; - the minimum oil passage cross-section of the second channels is defined by flow restrictors mounted in the second channels; - the minimum oil passage cross-section of the first channels is defined by the first channels themselves; - the ratio between the minimum oil passage area of the first channels and the minimum oil passage area of the second channels is between 2 and 10, and preferably between 3 and 5; - the first channels have an L-shape, their radially external ends being bent at right angles; - the second channels extend at least partially radially with respect to the axis and have radially internal ends connected to the second groove and radially external ends connected to the ports or the first channels; - the second channels have an L-shape, their radially external ends being bent at right angles; - the second channels extend axially between the first and second grooves.
[0030] The present invention also relates to a mechanical gearbox for an aircraft turbomachine, this gearbox comprising:
[0031] - a solar panel centered on an axis,
[0032] - a fixed crown extending around the axis and the solar element,
[0033] - satellites mounted between the solar system and the corona and meshed with the solar system and the crown,
[0034] - a satellite carrier that supports the satellites and is mobile in rotation around the axis, and
[0035] - a device such as described above which is centered on the axis and which is fixed to the carrier- satellites, the hub ports opening into internal lubrication cavities for the satellite bearings.
[0036] The satellites are preferably guided in rotation by bearings, of the plain or hydrodynamic type. The internal cavities of the bearings are supplied with oil by the device in order to form oil films between the bearings and the satellites.
[0037] The present invention also relates to an assembly comprising a reducer as described above and at least one oil jet capable of projecting oil into the first and second grooves of the wheel.
[0038] A single nozzle may be capable of projecting oil into the first and second grooves. Alternatively, two separate nozzles may be capable of projecting oil into the first and second grooves respectively. Brief description of the figures
[0039] Other features and advantages of the invention will become apparent upon reading the detailed description that follows, for an understanding of which reference should be made to the accompanying drawings in which:
[0040] [Fig.1] [Fig.1] is a schematic half-view in axial cross-section of an aircraft turbomachine,
[0041] [Fig.2] [Fig.2] is a half axial cross-sectional view of an epicycloidal reducer,
[0042] [Fig.3] [Fig.3] is a schematic half-view in axial section of a device oil supply according to an embodiment of the invention,
[0043] [Fig.4] [Fig.4] is a schematic half axial cross-sectional view of a variant of implementation of the oil supply device according to the invention,
[0044] [Fig.5] [Fig.5] is a schematic half-view in axial section of an alternative embodiment of the oil supply device according to the invention,
[0045] [Fig.6] [Fig.6] is a schematic half-view in axial section of an alternative embodiment of the oil supply device according to the invention,
[0046] [Fig.7] [Fig.7] is a schematic half-view in axial section of an alternative embodiment of the oil supply device according to the invention,
[0047] [Fig.8] [Fig.8] is a schematic half-view in axial section of an alternative embodiment of the oil supply device according to the invention,
[0048] [Fig.9] [Fig.9] is a schematic half-view in axial section of an alternative embodiment of the oil supply device according to the invention,
[0049] [Fig. 10] [Fig. 10] is a schematic half axial cross-sectional view of an alternative embodiment of the oil supply device according to the invention. Detailed description of the invention
[0050] Fig. 1 shows a turbomachine 1 which includes, in a conventional manner, a blower propeller S, a low-pressure compressor 1a, a high-pressure compressor 1b, an annular combustion chamber 1e, a high-pressure turbine Id, a low-pressure turbine 1e and an exhaust nozzle Ih.
[0051] The high-pressure compressor 1b and the high-pressure turbine Id are connected by a high-pressure shaft 2 and together form a high-pressure (HP) unit. The low-pressure compressor la and the low-pressure turbine le are connected by a low-pressure shaft 3 and together form a low-pressure (LP) unit.
[0052] The blower propeller S is driven by a blower shaft 4 which is coupled to the BP shaft 3 by means of an epicyclic gear reducer 10 represented here schematically.
[0053] The reducer 10 is positioned in the front part of the turbomachine 1. A fixed structure schematically comprising, here, an upstream part 5a and a downstream part 5b is arranged to form an enclosure El surrounding the reducer 10.
[0054] This enclosure El is here closed upstream by seals at the level of a bearing allowing the passage of the blower shaft 4, and downstream by seals at the level of the passage of the BP shaft 3.
[0055] With reference to [Fig. 2], the reducer 10 comprises a ring gear 14 which is fixed by means of a ring carrier (not shown) to the fixed structure 5a, 5b with flexible means arranged to allow it to follow any movements of the blower shaft 4, for example in certain degraded operating conditions. In a planetary configuration, the ring carrier consists of a more or less flexible part that drives the ring gear and a part held by bearings or bearings and on which the blower is mounted. These fastening methods are known to those skilled in the art and are not detailed here. A brief description can be found, for example, in FR-A1-2 987 416.
[0056] The reducer 10 engages on one side with the BP 3 shaft via splines 7 which drive a planetary or solar gear pinion 11, and on the other side with the blower shaft 4 which is attached to a planet carrier 13. Conventionally, the solar 11, whose axis of rotation X coincides with that of the turbomachine 1, drives a series of planetary gears or planets 12, which are regularly distributed around the circumference of the reducer 10. The number of planets 12 is generally defined between three and seven.
[0057] The satellites 12 also rotate around the X axis of the turbomachine 1 except in the case of a planetary architecture where they rotate only around their axes of revolution, by meshing with internal teeth of the ring 14, which is fixed to a stator of the turbomachine 1 by means of flanges 20 in the case of an epicyclic architecture or fixed to a rotor of the turbomachine in the case of the planetary architecture.
[0058] Each of the satellites 12 rotates freely around a satellite axis / bearing 16 connected to the satellite carrier 13, using a bearing which can be smooth, as shown in [Fig.2], or a rolling element bearing (ball or roller bearings).
[0059] The rotation of the satellites 12 around their satellite axes 16, due to the cooperation of their pinions with the teeth of the ring 14, causes the rotation of the satellite carrier 13 around the X axis, and consequently that of the blower shaft 4 which is linked to it, at a rotational speed which is lower than that of the BP shaft 3.
[0060] Figure 2 shows the oil supply to the reducer 10 and its path within it. Arrows on Figure 2 show the path followed by the oil from, in this example, a buffer tank connected to the fixed structure of the turbomachine 1, to the gears and bearings to be lubricated.
[0061] The lubrication device includes in particular a first part linked to the fixed structure and delivering the oil to the rotating parts of the reducer 10, and a supply device 22 rotating with the planet carrier s 13 and receiving this oil in the case of a reducer qualified as "epicycloidal" (epicycloidal architecture commonly referred to as "planetary" in English-language literature).
[0062] The device 22 comprises a wheel 24 which has a generally annular shape around the axis X and which includes:
[0063] - a first annular groove 26 opening radially inwards to the oil supply to the device 22 by spraying oil into the groove 26,
[0064] - of the first internal channels 28 extending at least partly radially by relative to the X-axis and comprising radially internal ends 28a connected to the first groove 26 and radially external ends 28b connected to oil supply ports 30 of the reducer 10, these ports 30 opening in the axial direction, and
[0065] - a second annular groove 32 opening radially inwards to the oil supply of the device 22 by spraying oil into the groove 32, the first and second grooves 26, 32 being adjacent.
[0066] The oil is projected into the grooves 26, 32 by one or more nozzles 34. The same nozzle may be capable of projecting oil into the first and second grooves 26, 32, as in the example shown. Alternatively, two separate nozzles could be capable of projecting oil into the first and second grooves 26, 32 respectively.
[0067] The first groove 26 supplies oil to the first channels 28 by centrifugation, the oil circulating in these channels 28 to the ports 30 for the purpose of lubricating the bearings of the satellites 12 in the example shown.
[0068] The first groove 26 could also be connected to other oil supply channels 36 for jets 38, for example, these jets 38 being located in the reducer 10 and intended to project oil onto gears.
[0069] According to the invention, the second groove 32 is connected to the ports 30, or to the first channels 28 or to the first groove 26 by second channels 40 which have a minimum oil passage section less than a minimum oil passage section of the first channels 28.
[0070] Figures 3 to 10 illustrate several embodiments of the power supply device 22.
[0071] It is important to note that these figures show half of an axial section of this device 22, the device 22 and its wheel 24 having a general annular shape around the axis X.
[0072] It is also important to note that the device 22 can take the general form:
[0073] - of a disk centered on this X axis, and having on its inner periphery the grooves 26, 32, the channels 28, 40 extending inside the annular wall of the disc, or
[0074] - of a ring centered on the X-axis and around which arms extend radially distributed around the X axis, the grooves 26, 32 being made in the ring and the channels 28, 40 being formed inside the arms.
[0075] In Figures 3 to 10, the elements already described above are designated by the same reference numerals. Furthermore, the minimum oil passage cross-section of the first channels 28 is denoted SI, and the minimum oil passage cross-section of the second channels 40 is denoted S2.
[0076] The SI / S2 ratio is between 2 and 10, and preferably between 3 and 5.
[0077] In all of these figures, the first groove 26 and the ports 30 are located on the same axial side of the device 22 although this aspect is not limiting.
[0078] As in the examples shown, the first channels 28 have an L-shape, their radially external ends 28b being bent at right angles.
[0079] Fig. 3 represents a first embodiment in which the minimum oil passage section S2 of the second channels 40 is defined by flow restrictors 42 mounted in the second channels 40.
[0080] The second channels 40 extend radially with respect to the X axis and have radially internal ends 40a connected to the second groove 32 and radially external ends 40b connected to the ports 30.
[0081] The second channels 40 have an L-shaped form in the example shown, their radially external ends 40b being bent at right angles.
[0082] A flow restrictor 42 is mounted in each of the channels 40, in particular in its radially internal end 40a.
[0083] Figure 4 represents an alternative embodiment in which the minimum section of Oil passage S2 of the second channels 40 is defined by flow restrictors 42 mounted in the second channels 40.
[0084] The second channels 40 extend radially with respect to the X axis and have radially internal ends 40a connected to the second groove 32 and radially external ends 40b connected to the ports 30.
[0085] The second channels 40 have an L-shaped form in the example shown, their radially external ends 40b being bent at right angles.
[0086] A flow restrictor 42 is mounted in each of the channels 40, in particular in its radially external end 40b.
[0087] Figure 5 represents an alternative embodiment in which the minimum oil passage section S2 of the second channels 40 is defined by the second channels 40 themselves.
[0088] The second channels 40 extend radially with respect to the X axis and have radially internal ends 40a connected to the second groove 32 and radially external ends 40b connected to the ports 30.
[0089] The second channels 40 have an L-shaped form in the example shown, their radially external ends 40b being bent at right angles.
[0090] The portion 40c of each conduit 40, which extends radially outwards from the end 40a, defines the cross-section S2, which is constant over all or part of the length of this portion 40c. The portion 40d of each conduit 40, which forms part of the radially external end 40b of the conduit and extends axially to the port 30, has a cross-section S3 that is larger than the cross-section S2. This cross-section S3 is constant over all or part of the length of this portion 40d and may be close to or equal to the cross-section SL
[0091] Figure 6 represents an alternative embodiment in which the minimum oil passage cross-section S2 of the second channels 40 is defined by the second channels 40 themselves. same.
[0092] The second channels 40 extend radially with respect to the X axis and have radially internal ends 40a connected to the second groove 32 and radially external ends 40b connected to the ports 30.
[0093] The second channels 40 have an L-shaped form in the example shown, their radially external ends 40b being bent at right angles.
[0094] The portion 40d of each conduit 40, which forms part of the radially external end 40b of the conduit and extends axially to the port 30, defines the cross-section S2, which is constant over all or part of the length of this portion 40d. The portion 40c of each conduit 40, which extends radially outward from the end 40a, has a cross-section S3 that is larger than the cross-section S2. This cross-section S3 is constant over all or part of the length of this portion 40d. This cross-section S3 may be close to or equal to the cross-section SL
[0095] Figure 7 represents an alternative embodiment in which the minimum oil passage section S2 of the second channels 40 is defined by flow restrictors 42 mounted in the second channels 40.
[0096] The second channels 40 extend radially with respect to the X axis and have radially internal ends 40a connected to the second groove 32 and radially external ends 40b connected to the first channels 28 and in particular to their radially external ends 28b.
[0097] The second channels 40 have an L-shaped form in the example shown, their radially external ends 40b being bent at right angles.
[0098] A flow restrictor 42 is mounted in each of the channels 40, in particular in its radially internal end 40a.
[0099] Fig. 8 represents an alternative embodiment in which the minimum oil passage section S2 of the second channels 40 is defined by the second channels 40 themselves.
[0100] The second channels 40 extend radially with respect to the X axis and have radially internal ends 40a connected to the second groove 32 and radially external ends 40b connected to the first channels 28 and in particular to their radially external ends 28b.
[0101] The second channels 40 have an L-shaped form in the example shown, their radially external ends 40b being bent at right angles.
[0102] The portion 40c of each conduit 40, which extends radially outwards from the end 40a, defines the section S2, which is constant over all or part of the length of this portion 40c. The portion 40d of each conduit 40, which forms part of the radially external end 40b of the conduit and extends axially to the channel 28, has a section S3 that is larger than the section S2. This section S3 is constant over all or part of the length of this part 40d. This section S3 may be close to or equal to the section SI.
[0103] Fig. 9 represents an alternative embodiment in which the minimum oil passage section S2 of the second channels 40 is defined by the second channels 40 themselves.
[0104] The second channels 40 extend axially, therefore along the X axis, between the two grooves 26, 32.
[0105] The section S2 of each channel 40 is preferably constant over its entire length.
[0106] Fig. 10 represents an alternative embodiment in which the minimum oil passage section S2 of the second channels 40 is defined by flow restrictors 42 mounted in the second channels 40.
[0107] The second channels 40 extend axially, therefore along the X axis, between the two grooves 26, 32.
Claims
Demands
1. An oil supply device (22) for a mechanical gearbox (10) of an aircraft turbomachine (1), said device (22) comprising a wheel (24) having a generally annular shape about an axis (X) and comprising: - a first annular groove (26) opening radially inward for supplying oil to the device (22) by spraying oil into the groove (26), - first internal channels (28) extending at least partially radially with respect to the axis (X) and comprising radially internal ends (28a) connected to the first groove (26) and radially external ends (28b) connected to oil supply ports (30) of the gearbox (10), these ports (30) opening in an axial direction, characterized in that it further comprises: - a second annular groove (32) opening radially inward for supplying oil from the device (22) by spraying oil into the throat (32),the first and second grooves (26, 32) being adjacent, the second groove (32) being connected to said ports (30) or to said first channels (28) or to said first groove (26) by second channels (40) which have a minimum oil passage cross-section (S2) less than a minimum oil passage cross-section (SI) of the first channels (28).
2. Device (22) according to claim 1, characterized in that the minimum oil passage cross-section (S2) of the second channels (40) is defined by the second channels (40) themselves.
3. Device (22) according to claim 1, characterized in that the minimum oil passage cross-section (S2) of the second channels (40) is defined by flow restrictors (42) mounted in the second channels (40).
4. Device (22) according to any one of the preceding claims, characterized in that the minimum oil passage cross-section (SI) of the first channels (28) is defined by the first channels (28) themselves.
5. Device (22) according to any one of the preceding claims, characterized in that the ratio between the minimum oil passage area (SI) of the first channels (28) and the minimum oil passage area (S2) of the second channels (40) is between 2 and 10, and preferably between 3 and 5.
6. Device (22) according to any one of the preceding claims, characterized in that the first channels (28) have an L-shaped form, their radially external ends (28b) being bent at right angles.
7. Device (22) according to any one of claims 1 to 6, characterized in that the second channels (40) extend at least partly radially with respect to the axis (X) and have radially internal ends (40a) connected to the second groove (32) and radially external ends (40b) connected to the ports (30) or to the first channels (28).
8. Device (22) according to the preceding claim, characterized in that the second channels (40) have an L-shape, their radially external ends (40b) being bent at right angles.
9. Device (22) according to any one of claims 1 to 6, characterized in that the second channels (40) extend axially between the first and second grooves (26, 32).
10. Mechanical reducer (10) for an aircraft turbomachine (1), this reducer comprising: - a sun (11) centered on an axis (X), - a fixed ring gear (14) extending around the axis (X) and the sun gear (H), - satellites (12) mounted between the sun gear (11) and the ring gear (14) and meshed with the sun gear (11) and the ring gear (14), - a satellite carrier (13) which supports the satellites (12) and which is movable in rotation about the axis (X), and - a device (22) according to any one of the preceding claims which is centered on the axis (X) and which is fixed to the satellite carrier (13), the ports (30) of the impeller (24) opening into internal bearing lubrication cavities of the satellites (12).
11. Assembly comprising a reducer (10) according to claim 10 and at least one oil jet (34) capable of projecting oil into the first and second grooves (26, 32) of the wheel (24).
12. Assembly according to claim 11, wherein a single nozzle (34) is capable of projecting oil into the first and second grooves (26, 32), or two separate nozzles (34) are capable of projecting oil respectively into the first and second grooves (26, 32).