Oil distribution wheel for a speed reducer

Abstract

An oil distribution impeller (10) for a speed reducer, comprising: - a strainer (24) disposed transversely in the distribution conduit (16), adapted to filter an oil flow (F) flowing in the distribution conduit, and - a discharge conduit (26) downstream of the strainer. The impeller includes a control device (30) for a discharge flow (F') through the discharge conduit, comprising: - a shut-off member (32) movably mounted between a forward position and a closed position, the shut-off member being arranged to be forced towards its closed position by a centrifugal force during rotation of the impeller, - a return member (34) arranged to force the shut-off member (32) towards its forward position. Figure to be published with the abbreviation: 2

Description

Title of the invention: Oil distribution wheel for a speed reducer. Technical field of the invention

[0001] The invention relates to an oil distribution wheel for a speed reducer, in particular with an epicyclic or differential gear, for example installed in a double-flow turbomachine, in particular a turbomachine of an aircraft. Prior art

[0002] The role of a mechanical reducer is to modify the speed and torque ratio between the input shaft and the output shaft of a mechanical system.

[0003] New generations of turbofan engines, particularly those with a very 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 X of the turbomachine. The planet gears each have a different axis of revolution, equally spaced on the same operating diameter around the axis of the planetary gears. These axes are parallel to the longitudinal axis X.

[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 field.

[0010] There are several types of contact meshing such as with straight, helical or chevron teeth.

[0011] The present application relates to the problem of lubrication of these complex rotating elements, in the specific case of an epicyclic type reducer with one or more stages, i.e. with rotating planet carrier and fixed ring, or differential, in which none of these elements is fixed in rotation.

[0012] For this purpose, it is known to employ oil supply and oil distribution devices within the reducer designated by the term centrifugal impellers. Examples of such centrifugal impellers are described, among others, in documents FR 2987416 Al, FR 3041054 Al and EP 3822515 Al.

[0013] Such an impeller allows the oil distributed by one or more oil jets mounted on the engine frame, i.e., the fixed reference frame, to be recovered in a rotating oil recovery cavity, or distributor, comprising an annular opening opposite said jets. The rotation of the impeller drives the oil from the distributor into one or more oil distribution circuits attached to the rotating reference frame, which distribute the oil to the various mechanical components to be lubricated (typically the gears and bearings of the planetary gears). The distribution circuits are oriented at least partially radially away from the axis of rotation, so that the rapid rotation creates centrifugal pressure in the oil column within the distribution circuits, ensuring the flow of oil.

[0014] The advantages conferred by such systems include the possibility of transferring oil from the fixed reference frame (engine frame) to the rotating reference frame (satellite carrier), the absence of wear parts (no seals, no friction...) and performance independent of misalignments between the different components in the engine (frame, turbine, reducer...), which greatly improves the durability and reliability of these systems.

[0015] However, the use of an oil jet and an open oil receiving cavity creates a discontinuity in the oil flow insulation, allowing it to be contaminated by solid particles, for example, from the wear of a part in the engine environment. Such solid particles can then enter the impeller at the cavity and follow the distribution circuit to the lubricated components, which can lead to accelerated wear of these components.

[0016] A known solution to this problem is shown in [Fig. 1]. A wheel 10 is shown partially in cross-section along a radial plane. The wheel 10 includes an oil recovery cavity 12, having an opening 14 oriented radially towards the axis of rotation and facing at least one oil jet 15 designed to generate an oil jet J. An oil distribution conduit 16 extends from the cavity 12 and comprises a first substantially radial portion 18 and a second substantially axial portion 20, which opens through an oil distribution opening 22 onto the components to be lubricated.

[0017] An oil flow F is formed from the cavity 14 into the distribution conduit 16, under the effect of the pressure generated by the centrifugal force resulting from the rotation of the impeller around the central axis A on the column of oil present in the first portion 18.

[0018] A strainer 24 is disposed in the distribution conduit 16 of the impeller 10, in the second substantially axial portion 20. The strainer 24 is arranged to filter the oil flow F and block the passage of fine particles through the distribution conduit 16.

[0019] In order to evacuate the particles which could clog the strainer 24, a radial drilling is made in the walls of the distribution circuit 16, upstream of the strainer 24, for example in the extension of the first portion 18, in order to make an evacuation conduit 26 of the filtered particles out of the distribution circuit.

[0020] An evacuation flow F' flows through said evacuation conduit 26 outside the frame and away from the parts to be lubricated.

[0021] This type of device satisfactorily fulfills the desired filtration function and prevents the strainer from clogging with filtered particles. However, it can still be improved.

[0022] Indeed, the presence of the drain pipe results in a continuous oil leakage rate when the rotating assembly is in motion due to the operation of the gearbox. On the one hand, this lost oil flow is carried along by the rotating parts of the engine and generates power losses through turbulence. On the other hand, this oil loss must be taken into account when sizing the lubrication system, particularly for the on-board oil reservoirs and the corresponding distribution system, which leads to an unnecessary additional cost and an unintended increase in the on-board weight. Presentation of the invention

[0023] The invention aims to remedy these drawbacks. To this end, the invention relates to an oil distribution wheel for a speed reducer, the wheel comprising:

[0024] - a substantially annular frame having a central axis, the frame being intended to be attached to a planetary mount of the speed reducer,

[0025] - an oil receiving cavity opening in the frame through an oriented opening radially towards the central axis,

[0026] - at least one oil distribution conduit extending from the cavity and opening through a distribution port arranged to open opposite the components of the speed reducer requiring lubrication,

[0027] - a strainer arranged across the distribution conduit, suitable for filtering a flow oil flowing into the distribution channel, and

[0028] - a drain pipe opening into the distribution pipe downstream of the strainer and outlet via a drain opening arranged to open away from the parts to be lubricated,

[0029] characterized in that the wheel further comprises a device for controlling an evacuation flow through the evacuation conduit, said control device comprising:

[0030] - a movable, mounted shuttering element between a passing position in which The sealing device allows the passage of the evacuation flow through the evacuation conduit and a blocking position in which the sealing device prevents the passage of the evacuation flow through the evacuation conduit, the sealing device being arranged to be forced into its blocking position by a centrifugal force during the rotation of the impeller around the central axis,

[0031] - a return member arranged to urge the obturating member towards its position passerby.

[0032] Such a wheel makes it possible to block the oil leakage flow during high-speed rotation of the speed reducer, i.e. when said leakage flow would be the highest, while allowing the oil and particles to be evacuated at low speed and when stopped.

[0033] Said speed reducer is for example an epicyclic or differential gear reducer.

[0034] The intensity of the stress exerted by the return member can be selected so as to reach the locking position of the locking member only above a predetermined rotation speed of the wheel.

[0035] The diameters and / or effective flow sections of the second portion of the distribution conduit and the discharge conduit can be determined so as to have oil flow preferentially in the discharge conduit when the latter is not closed by the sealing device.

[0036] Each distribution conduit may include a first portion extending substantially radially from the cavity and a second portion extending substantially axially and opening through the distribution opening, the strainer being fixed at the level of the inlet of the second portion and extending axially partially across the first portion.

[0037] Such a feature allows a part of the strainer to be placed across the oil flow in the first portion of the conduit, which facilitates the cleaning of filtered particles.

[0038] The evacuation conduit can extend substantially axially from the distribution conduit and preferably to the evacuation opening.

[0039] Such a feature makes it possible to use a radially moving switching element, using the mass of the element to actuate it under the effect of centrifugal force.

[0040] The return member may be a spring, one end of which is fixed to the frame and the other end of which is fixed to the sealing member.

[0041] Such a feature makes it possible to exert a substantially linear restoring force on the closing member, which facilitates the adjustment of the force applied to reach the locking position only above a predetermined rotational speed.

[0042] The sealing member can be a movable plug mounted to slide in a substantially radial switching conduit, intersecting the discharge conduit, the return member being disposed in the switching conduit, fixed by a first end to a radially internal end of the switching conduit and by a second end to the movable plug.

[0043] The sealing member can be a movable plug mounted to slide in a substantially radial switching conduit, intersecting the evacuation conduit, the return member being disposed compressed in the switching conduit, supported by a first end against a radially external end of the switching conduit and by a second end against the movable plug.

[0044] These characteristics allow for a reliable and robust structure of the sealing and return mechanisms, which offer good durability and simple manufacturing.

[0045] The sealing member may include a butterfly mounted in the evacuation conduit, movable in rotation about a substantially circumferential axis between the blocking position in which the butterfly extends entirely across the evacuation conduit and the passing position in which a circulation space is left free between the butterfly and the walls of the evacuation conduit, the return member being arranged to force the butterfly towards its passing position, the sealing member also including a weight fixed to the butterfly away from the axis of rotation, so that the centrifugal force during the rotation of the wheel about the central axis forces the butterfly towards its blocking position.

[0046] Such a feature allows the use of a rotating part for the sealing element, which reduces the risks of blockage compared to a sliding plug.

[0047] The shut-off device may comprise a flap fixed to the frame external to the discharge duct, mounted to rotate about a circumferential axis between the blocking position in which the flap is pressed against and closes the discharge opening and the passing position in which the flap is away from the discharge opening, the return mechanism being arranged to move the flap towards its passing position, the shut-off device also comprising a weight fixed to the flap at the passing position of the axis of rotation, so that the centrifugal force during the rotation of the wheel around the central axis forces the valve towards its locking position.

[0048] Such a feature allows the sealing element and the return element to be located outside the oil circulation network.

[0049] The sealing member may include a radially movable plug, the discharge conduit opening into the distribution conduit by a substantially radial inlet arranged to form a seat for said plug, the plug bearing against said seat and sealing the inlet of the discharge conduit in the blocking position and being away from the seat and allowing the passage of oil through the inlet of the discharge conduit in the passing position, the return member being an elastic spring mounted compressed between the seat and the plug.

[0050] Such a feature allows for a compact and robust structure of the closing and return mechanisms.

[0051] The invention also relates to an assembly for an aircraft turbomachine, comprising:

[0052] - a speed reducer,

[0053] - at least one oil jet intended to be mounted on a fixed structure of the turbomachine, adapted to project at least one jet of oil,

[0054] - an oil distribution wheel as above, the frame of said wheel being fixed to a planet carrier of the speed reducer, the wheel and the planet carrier being mobile in rotation around the central axis, the cavity of the wheel being arranged opposite at least one nozzle in order to collect at least one jet of oil, the distribution opening opening opposite elements to be lubricated of the reducer and the discharge opening opening away from the elements to be lubricated.

[0055] Said speed reducer is for example an epicyclic or differential gear reducer. Brief description of the figures

[0056] [Fig-1] is a partial cross-sectional view in a radial plane of a prior art oil distribution wheel,

[0057] [Fig.2] [Fig.3] are partial cross-sectional views in a radial plane of a spinning wheel oil distribution according to a first embodiment of the invention, respectively in a passing position and in a blocking position of a sealing element,

[0058] [Fig.4] is a partial cross-sectional view in a radial plane of a timing wheel of oil according to a second embodiment of the invention, in a through position of a sealing element,

[0059] [Fig.5] [Fig.6] are partial cross-sectional views in a radial plane of a spinning wheel oil distribution according to a third embodiment of the invention, respectively in a passing position and in a blocking position of a sealing element, and

[0060] [Fig.7] [Fig.8] are cross-sectional diagrams in a radial plane of a spinning wheel oil distribution according to a fourth embodiment of the invention, respectively in a passing position and in a blocking position of a sealing element. Detailed description of the invention

[0061] An oil distribution wheel 10 for an epicyclic or differential gear reducer according to a first embodiment of the invention is shown in Figures 2 and 3. The wheel 10 is fixedly mounted on a planet carrier of the gear reducer, so that the rotational movement of the planet carrier causes the wheel 10 to rotate.

[0062] The spinning wheel 10 is shown partially in section along a radial plane.

[0063] The spinning wheel 10 comprises a frame 11 that is substantially annular around a central axis A, which is the axis of rotation of the wheel 10 during its movement accompanying the planet carrier of the reducer, said central axis A being coincident with the axis of rotation of the planet carrier.

[0064] The terms "axial", "radial" and "circumferential", as well as the terms "internal" and "external", are understood in relation to the central axis A.

[0065] The term "substantially" is used relative to a direction to indicate a small angular deviation from said direction, for example less than or equal to 10° and in particular less than or equal to 5°.

[0066] As described previously, the wheel 10 includes an oil recovery cavity 12, having an opening 14 oriented radially towards the axis of rotation and facing at least one oil jet 15 suitable for generating an oil jet J. A plurality of oil distribution channels 16 extend from the cavity 12, each distribution channel 16 comprising a first substantially radial portion 18 and a second substantially axial portion 20, which opens through an oil distribution opening 22 opposite the parts to be lubricated.

[0067] An oil flow F is formed from the cavity 14 into the distribution conduit 16, under the effect of the pressure generated by the centrifugal force resulting from the rotation of the impeller around the central axis A on the column of oil present in the first portion 18.

[0068] A strainer 24 is disposed in the distribution conduit 16 of the impeller 10, in the second substantially axial portion 20. The strainer 24 is arranged to filter the flow oil F and block the passage of fine particles through the distribution conduit 16.

[0069] According to the first embodiment of the invention, the wheel 10 includes an evacuation conduit 26 which opens into the distribution conduit 16 downstream of the strainer 24 and extends substantially axially to an evacuation opening 28 arranged away from the elements to be lubricated.

[0070] For example, the drain duct 26 extends in a direction opposite to the direction of the second portion 20 of the distribution duct, so that the drain opening 28 opens on the side of the frame 11 opposite to the distribution opening 22.

[0071] Advantageously, the strainer 24 is fixed at the inlet of the second portion 20 and extending axially partially across the first portion 18, so that the passage of the oil flow F' through the first portion 18 to the discharge conduit 26 partially passes through the strainer 24 to detach said filtered particles.

[0072] According to the invention, the wheel 10 includes a control device 30 provided to control the flow of an evacuation flow F' of oil through the evacuation conduit 26 to the evacuation opening 28.

[0073] Said control device 30 includes a sealing member 32 of the evacuation conduit 26 and a return member 34.

[0074] Generally, the sealing member 32 is mounted movably between a passing position in which the sealing member 32 allows the passage of the evacuation flow F' through the evacuation conduit 26 and a blocking position in which the sealing member 32 prevents the passage of the evacuation flow F' through the evacuation conduit 26.

[0075] The sealing member 32 is arranged to be forced towards its locking position under the effect of the centrifugal force exerted by the rotation of the wheel 10 around the central axis A.

[0076] Conversely, the return member 34 is arranged to urge the obturator member 32 towards its passing position.

[0077] The competition between the stresses exerted by the return member 34 and the centrifugal force allows the locking member 32 to adopt its passing position below a certain predetermined critical rotation speed of the wheel 10 and to adopt its locking position beyond this predetermined critical rotation speed of the wheel 10. The determination of this critical transition rotation speed depends on the exact respective natures of the locking member 32 and the return member 34.

[0078] The diameters and / or effective flow sections of the second portion 20 of the distribution conduit 16 and of the discharge conduit 26 are advantageously determined so as to have oil flow preferentially into the drain conduit 26 when it is not blocked by the sealing device 32. Care is taken in particular to ensure that the pressure drop of the drain flow F' is less than the pressure drop of the distribution flow F. Thus, at low rotational speed of the impeller 10, the oil preferentially uses the drain conduit and removes the particles filtered in the strainer 24. At high rotational speeds, the drain conduit 36 ​​is blocked and the oil uses the second portion 20 of the distribution conduit 16, is filtered by the strainer 24, and lubricates the parts to be lubricated, such as the gears of the gearbox satellites, when this is most necessary.

[0079] In the first embodiment shown in Figures 2 and 3, the sealing member 32 is a movable plug mounted to slide in a substantially radial switching conduit 36, intersecting the discharge conduit 26.

[0080] The plug has a substantially cylindrical shape, with a diameter substantially equal to the diameter of the switching conduit 36 ​​and a height greater than a diameter of the evacuation conduit 26 at the level of the intersection with the switching conduit 36, so that the plug can block the passage of the evacuation flow F' through the intersection between the evacuation conduit 26 and the switching conduit 36.

[0081] This position of the plug across the intersection of the switching conduit 36 ​​and the evacuation conduit 26, shown in [Fig.3], constitutes the blocking position of the sealing member 32.

[0082] The switching conduit 36 ​​extends for example substantially perpendicularly to the evacuation conduit 26, and includes a portion of housing which extends radially inwards beyond the intersection, over a length sufficient to receive at least partially the plug, so as to leave at least part of the intersection between the evacuation conduit 26 and the switching conduit 36 ​​free and allow the passage of evacuation flow F'.

[0083] The position of the plug received at least partially in the portion of housing 38, shown in [Fig.2], corresponds to the passing position of the locking member 34.

[0084] The return member 34 is a spring, one end of which is fixed to the frame 11 and the other end is fixed to the sealing member 32.

[0085] More specifically, the return member 34 is disposed in the switching conduit 36, fixed by a first end to a radially internal end of the switching conduit 36 ​​and by a second end to the movable plug.

[0086] Thus, the return member 34 exerts an elastic return force on the movable plug that depends linearly on the deformation exerted on the return member 34 by the movement of the plug in the switching conduit 36. The return member 34 presents a rest length sufficiently small so that in the absence of any other force exerted on the movable stopper, it is in a passing position.

[0087] In the passing position shown in [Fig.2], the rotation of the wheel is sufficiently small, or even zero, so that the centrifugal force exerted by the rotation is sufficiently less than said elastic restoring force so that the plug is globally stressed by the resultant of these forces in the direction of the portion of housing 38.

[0088] In the blocking position, shown in [Fig.3], the centrifugal force is sufficient to extend the return member 34 until the plug is across the intersection, in equilibrium of the two forces, or even in contact with the radially external end of the switching conduit 38. For this, the radially external end of the switching conduit 38 is provided sufficiently close to the intersection so that the length of the plug allows the intersection to be blocked when it is in contact with this radially external end.

[0089] This ensures that the plug is in a locking position for high rotational speeds, without it exceeding the intersection in the event of very high stress at very high speed.

[0090] According to a variant (not shown) of this embodiment, the housing portion 38 is radially external to the intersection between the evacuation conduit 26 and the switching conduit 36, the return member 34 being disposed in said housing portion, compressed between the plug and the radially external end of the housing portion 38.

[0091] In this case, the return member has a rest length sufficiently large so that in the absence of other forces applied to the plug, the return member pushes the plug against the radially internal end of the switching conduit, the plug then leaving the intersection free for the passage of the evacuation flow F'.

[0092] When the rotational speed of the wheel is sufficient, the centrifugal force applied to the movable plug compresses the spring and stresses the plug across the intersection, blocking the evacuation flow F'.

[0093] According to a second embodiment shown in [Fig. 4], the sealing member 32 comprises a butterfly 40 mounted in the discharge conduit 26, which is free to rotate about a substantially circumferential axis X. The operation of the impeller 10 according to this second embodiment is identical to that according to the first embodiment, except for the following.

[0094] The butterfly 40 is a plate, for example metallic, substantially flat having a contour identical to the transverse contour of the exhaust duct at the axis of rotation X, so that the butterfly 40 blocks the exhaust duct 26 and prevents the passage of the evacuation flow F' when it extends perpendicularly to the local direction of the evacuation conduit 26. This position of the butterfly 40 constitutes the blocking position of the obturator 32.

[0095] The passing position of the obturator 32, shown in [Fig.4], corresponds to the position of the butterfly 40 in which a circulation space is left free between the butterfly 40 and the walls of the evacuation conduit 26, the butterfly 40 extending in a plane forming a non-right angle with the local direction of the evacuation conduit 26.

[0096] The sealing member 32 also includes a weight 42 fixed to the butterfly 40 away from the axis of rotation X, so that the centrifugal force during the rotation of the wheel 10 around the central axis A forces the butterfly 40 towards its locking position, in which the weight 42 is located as far outwards as possible in the radial direction.

[0097] The return member 34 is arranged to move the butterfly 40 towards its passing position, that is to say to move it away from the blocking position.

[0098] The return member can for example be a spiral spring fixed at one end to the butterfly 40, away from the axis of rotation X, and at a second end to a radially internal wall of the evacuation conduit 26. Said spring is under tension and thus forces the butterfly 40 towards said wall, causing the butterfly 40 to rotate away from the blocking position.

[0099] Alternatively, the return member is for example a spring exerting a rotational torque on the butterfly 40, mounted at the rotation axis X of the butterfly 40 and arranged to stress it away from the blocking position.

[0100] According to a third embodiment shown in figures 5 and 6, the sealing member 32 comprises a valve 44 fixed to the frame 11 externally to the evacuation conduit 26.

[0101] The operation of the spinning wheel 10 according to this third embodiment is identical to that according to the first embodiment, with the exception of the following.

[0102] In this embodiment, the evacuation conduit 26 extends substantially radially, at least with regard to the part opening through the evacuation opening 28, which is oriented radially.

[0103] The valve 44 is mounted on the frame 11, which is movable in rotation around a substantially circumferential axis X between the blocking position, shown in [Fig.6], in which the valve 44 is against and closes the evacuation opening 28, and the passing position, shown in [Fig.5] in which the valve 44 is away from the evacuation opening 28.

[0104] The sealing member 32 also includes a weight 46 fixed to the valve 44 away from the axis of rotation X, so that the centrifugal force during the rotation of the wheel 10 around the central axis A forces the valve 44 towards its locking position. The ballast 46 is, for example, located at an edge of the valve 44 on the side opposite the discharge opening 28 relative to the axis of rotation X of the valve 44, so that the centrifugal force exerts a radial force on the ballast outwards, which drives the part of the valve 44 closing the discharge opening 28 radially inwards, against the discharge opening.

[0105] The return element 34, for example a spring, is arranged to force the valve 44 towards its open position. For example, one end of the spring is fixed to the valve 44 in the vicinity of the ballast 48, and the other end of the spring is fixed to the frame 11 at a point 48 located radially inward with respect to the valve 44. The spring is under tension and exerts a return force on the end of the valve 44, which carries the ballast radially inward and, by rotation, the part of the valve closing the discharge opening 28 radially outward, away from the discharge opening 28.

[0106] According to a fourth embodiment shown in figures 7 and 8, the sealing member 32 comprises a plug 50 mounted movably radially in the evacuation conduit 26.

[0107] The operation of the spinning wheel 10 according to this fourth embodiment is identical to that according to the first embodiment, with the exception of the following.

[0108] In this embodiment, the evacuation conduit 26 extends substantially radially, at least with regard to the part opening into the distribution conduit.

[0109] The opening of the discharge conduit 26 in the distribution conduit 16 is arranged to form a seat 52 for the plug 50, which acts as a valve closing the inlet of the discharge conduit 26 when it is forced against the seat 52 by the centrifugal force associated with the rotation of the wheel 10.

[0110] The plug 50 and the seat 52 have, for example, identical conical or frustoconical profiles in order to have respective contact surfaces blocking the flow of oil.

[0111] The return member 34 is a helical spring mounted radially between the plug 50 and the seat 52, so as to be compressed by the movement of the plug 50 towards the seat 52 under the effect of the centrifugal force during the rotation of the wheel 10 around the central axis A and thus to stress the plug 50 away from the seat 52.

[0112] The passing position is shown in [Fig. 7], and corresponds to the case where the rotation is slow or zero. The centrifugal force is then insufficient to force the plug 50 against the seat 52 and the passage of the discharge flow F' into the discharge conduit 26 is permitted.

[0113] The locking position is shown in [Fig. 8] and corresponds to the case where the rotation is faster than the critical rotational speed. The centrifugal force is then sufficient to force the plug 50 into a tight contact with the seat 52 and the passage The discharge flow F' in the discharge conduit 26 is then blocked. The oil is then redirected into the second portion 20 of the distribution conduit 16, through the strainer 24.

Claims

Demands

1. Oil distribution impeller (10) for a speed reducer, the impeller (10) comprising: - a substantially annular frame (11) having a central axis (A), the frame (11) being intended to be fixed to a planet carrier of the speed reducer, - an oil receiving cavity (12) opening in the frame (11) by means of an opening (14) oriented radially in the direction of the central axis (A), - at least one oil distribution conduit (16) extending from the cavity (14) and opening through a distribution opening (22) arranged to open opposite elements to be lubricated of the speed reducer, - a strainer (24) disposed across the distribution conduit (16), adapted to filter an oil flow (F) flowing in the distribution conduit (16),and - a discharge conduit (26) opening in the distribution conduit (16) downstream of the strainer (24) and discharging through a discharge opening (28) arranged to open away from the elements to be lubricated, characterized in that the impeller (10) further comprises a control device (30) for a discharge flow (F') through the discharge conduit, said control device comprising: - a shut-off member (32) movably mounted between a passing position in which the shut-off member (32) allows the discharge flow (F') to pass through the discharge conduit and a blocking position in which the shut-off member prevents the discharge flow (F') from passing through the discharge conduit, the shut-off member being arranged to be forced towards its blocking position by a centrifugal force during the rotation of the impeller about the axis central (A),- a return element (34) arranged to move the obturating element (32) towards its through position.

2. A wheel (10) according to claim 1, wherein each distribution conduit (16) comprises a first portion (18) extending substantially radially from the cavity (14) and a second portion (20) extending substantially axially and opening through the distribution opening (22), the strainer (24) being fixed at the level of the inlet of the second portion (20) and extending axially partially across the first portion (18).

3. Wheel (10) according to claim 1 or 2, in which the discharge conduit (26) extends substantially axially from the distribution conduit (16) and preferably to the discharge opening (28).

4. Wheel (10) according to any one of claims 1 to 3, wherein the return member (34) is a spring having one end fixed to the frame (11) and a second end fixed to the sealing member (32).

5. A wheel (10) according to any one of claims 1 to 4, wherein the sealing member (32) is a movable plug mounted to slide in a substantially radial switching conduit (36), intersecting the discharge conduit (26), the return member (34) being disposed in the switching conduit (36), fixed by a first end to a radially internal end of the switching conduit (36) and by a second end to the movable plug.

6. A wheel (10) according to any one of claims 1 to 4, wherein the sealing member (32) is a movable plug mounted to slide in a substantially radial switching conduit (36), intersecting the discharge conduit (26), the return member (34) being disposed compressed in the switching conduit (26), bearing by a first end against a radially external end of the switching conduit (36) and by a second end against the movable plug.

7. A screw (10) according to any one of claims 1 to 4, wherein the sealing member (32) comprises a butterfly (40) mounted in the discharge conduit (26), rotatable about a substantially circumferential axis (X) between the blocking position in which the butterfly (40) extends fully across the discharge conduit (26) and the passing position in which a clearance space is left between the butterfly (40) and the walls of the discharge conduit (26), the return member (34) being arranged to force the butterfly (40) towards its passing position, the sealing member (32) also comprising a weight (42) fixed to the butterfly (34) away from the axis of rotation (X), such that the force centrifugal force during the rotation of the wheel (10) around the central axis (A) forces the butterfly (40) towards its locking position.

8. Impeller (10) according to claim 1 or 2, wherein the sealing member (32) comprises a flapper (44) fixed to the frame (11) externally to the discharge conduit (26), mounted to rotate about a circumferential axis (X) between the blocking position in which the flapper (44) is pressed against and closes the discharge opening (28) and the passing position in which the flapper (44) is away from the discharge opening (28), the return member (34) being arranged to force the flapper (44) towards its passing position, the sealing member (32) also comprising a weight (46) fixed to the flapper (44) away from the axis of rotation (X), such that the centrifugal force during the rotation of the impeller (10) about the central axis (A) pushes the valve (44) towards its blocking position.

9. Impeller (10) according to claim 1 or 2, wherein the sealing member (32) comprises a radially movable plug (50), the discharge conduit (26) opening into the distribution conduit (16) by a substantially radial inlet arranged to form a seat (52) for said plug (50), the plug (50) bearing against said seat (52) and sealing the inlet of the discharge conduit (26) in the blocking position and being away from the seat (52) and allowing the passage of oil through the inlet of the discharge conduit (26) in the passing position, the return member (34) being an elastic spring mounted compressed between the seat (52) and the plug (50).

10. Assembly for an aircraft turbomachine, comprising: - a speed reducer, - at least one oil nozzle (15) for mounting on a fixed structure of the turbomachine, adapted to project at least one oil jet (J), - an oil distribution wheel (10) according to any one of claims 1 to 9, the frame (11) of said wheel being fixed to a planet carrier of the speed reducer, the wheel (10) and the planet carrier being rotatable about the central axis (A), the cavity (12) of the wheel (11) being disposed opposite at least one nozzle (15) in order to collect at least one oil jet (J), the distribution opening (22) opening opposite elements to be lubricated of the reducer and the discharge opening (28) opening away from the elements to be lubricated.

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