Module for an aircraft turbine engine

Abstract

The invention relates to a module (10) for an aircraft turbine engine, comprising: - a planetary reduction gear (14) comprising a rotatably movable sun gear (16), a rotatably movable ring gear (18), and planet gears (20) meshed with the sun gear (16) and the ring gear (18) and carried by a planet carrier (22), - an annular ring gear carrier (30) which comprises, at a downstream end, a first annular flange (30a) for attachment to the ring gear (18), and - an annular channel (50) which extends around the ring gear carrier (30) and which is located entirely upstream of the first flange (30a) of the ring gear carrier (30), and (50) comprising an annular cavity (52) into which first radial through-holes (48) open, for oil to pass therethrough, the through-holes being formed in the ring gear carrier (30) upstream of the first flange (30a).

Description

[0001] DESCRIPTION

[0002] TITLE: MODULE FOR AN AIRCRAFT TURBOMACHINE

[0003] Technical field of the invention

[0004] The present invention relates to a module for an aircraft turbomachine and to an aircraft turbomachine comprising such a module.

[0005] Technical background

[0006] The state of the art includes in particular documents FR-A1 -2 987 416, FR-A1 -3 041 054, FR-A1 -3 081 513, FR-A1 -3 094 01 1, FR-A1 -3 136 014, US-A1 -2023 / 417185 and US-B2-10,823,083.

[0007] The role of a mechanical reducer is to modify the speed and torque ratio between the input shaft and the output shaft of a mechanism.

[0008] Newer generations of turbofan engines, particularly those with a high bypass ratio, incorporate a mechanical gearbox to drive the fan shaft. Typically, the gearbox's purpose is to transform the high rotational speed of the power turbine shaft into a slower rotational speed for the fan shaft.

[0009] 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 the planet carrier. The sun gear, ring gear, and planet carrier are planetary gears because their axes of revolution coincide with the longitudinal X-axis of the turbomachine. The planet gears each have a different Y-axis of revolution, and they are evenly spaced around the same operating diameter of the planetary gears. These Y-axes are parallel to the longitudinal X-axis.

[0010] There are several gearbox architectures. In state-of-the-art turbomachinery, gearboxes are of the planetary or epicyclic type. In other similar applications, there are so-called differential or compound architectures. - In a planetary gearbox, the planet carrier is fixed, and the ring gear forms the output shaft of the device, rotating in the opposite direction to the sun.

[0011] - on an epicyclic reducer, the ring is fixed and the planet carrier constitutes the output shaft of the device which rotates in the same direction as the solar.

[0012] - On a differential gearbox, no element is fixed in rotation. The ring rotates in the opposite direction to the solar and satellite carrier.

[0013] Gearboxes can have one or more meshing stages. This meshing is achieved in various ways, such as by contact, friction, or magnetic fields. There are several types of contact meshing, such as with spur or herringbone teeth.

[0014] A gearbox requires lubrication, and supplying lubricating oil to its rotating components can be problematic. The oil is generally supplied to the gearbox via a lubricating oil distributor.

[0015] In the case of a planetary gearbox, the oil circulating in the gearbox to lubricate the rolling elements and the teeth is expelled peripherally by centrifugal force, through the ring which can rotate at up to about 3000 revolutions per minute.

[0016] It has already been proposed to install an oil collection and channeling gutter around the gear reducer ring, aligned with the ring's oil outlets. These oil outlets are formed in a ring mounting flange, and the gutter therefore extends around the ring flange.

[0017] One drawback of existing technologies concerns the bulkiness of the gutter and the realization of the oil passages in the reducer which is relatively complex and costly to make, particularly in the flange of the crown.

[0018] The invention aims to address at least some of these problems in a simple, efficient and economical way.

[0019] Summary of the invention

[0020] The invention relates to a module for an aircraft turbomachine, this module comprising: an annular stator housing extending around an axis, a planetary gearbox mounted at least partially inside the housing, the gearbox having a rotating sun gear about the axis, a rotating ring gear about the axis and the sun gear, and planet gears meshed with the sun gear and the ring gear and carried by a planet carrier fixed to the housing, an annular ring carrier extending around the axis and guided in rotation by bearings inside the housing, the ring carrier comprising at a downstream end a first annular flange for fixing to the ring gear, and an annular trough extending around the axis and the ring carrier and fixed to the housing, characterized in that the trough is located entirely upstream of the first flange of the ring carrier,and in that the gutter comprises an annular cavity which opens radially inwards and which is located radially opposite the first radial oil passages formed in the crown carrier upstream of said first flange.

[0021] In a planetary gearbox, the ring gear rotates freely, and the lubricating oil in contact with it is centrifuged. This oil passes through the first orifices and is projected directly into the trough cavity, thus minimizing the risk of loss and splashing. The trough is located entirely on one side, in this case the upstream side, of the ring gear flange, which reduces its overall size, particularly its radial dimensions.

[0022] The reducer according to the invention may comprise one or more of the following features, taken individually or in combination: the gutter comprises a first part which has a U-shaped axial cross-section to define said annular cavity, and a second part for connecting the first part to the housing; the first part has a maximum external diameter which is less than or equal to the maximum external diameter of said first flange; the second part comprises a second annular flange for fixing to the housing and an annular wall for connecting the second flange to the first part, this annular wall having a maximum external diameter which is less than or equal to the maximum external diameter of said second flange; the first and second parts are formed in one piece; the first orifices are formed in a cylindrical part of the crown carrier.This cylindrical part extending, for example, between a frustoconical portion and said first flange of the crown carrier, the first orifices open in the middle of said cavity, the planet carrier is fixed to the housing by means of an annular flange which extends around the shaft and the reducer, preferably predominantly or mainly, downstream of said first flange, the flange includes at a downstream end an annular flange for fixing to the planet carrier and at an upstream end another annular flange for fixing to the housing, this other flange being located, for example, upstream of said first flange, the crown includes second radial through-holes for oil passage, the second holes are located upstream of said first flange, and preferably downstream of the first holes, the module further includes an annular deflector which extends around the shaft and at least a portion of the reducer,The deflector having at one upstream end an annular flange for attachment to said first flange, the crown includes a radially external annular flange interposed axially between said first flange and the deflector flange, the crown flange having axial through-holes for oil passage from the inside of the deflector to the inside of the crown carrier, the gutter extending over 340° around the axis and including at least one radially external oil outlet opening located between 5 and 7 o'clock, and preferably at 6 o'clock, by analogy with the face of a clock centered on the axis; this method of positioning elements (by analogy with the face of a clock) is well known in the aeronautical field and in particular in a turbomachine. For example, 6 and 12 are vertically aligned, with 12 above 6. The invention also relates to an aircraft turbomachine,comprising a module as described above.

[0023] Brief description of the figures

[0024] The present invention will be better understood and other details, features, and advantages of the present invention will become more apparent upon reading the following description, with reference to the accompanying drawings in which:

[0025] [Fig.1] Figure 1 shows a schematic half-view in axial cross-section of a module according to the invention for an aircraft turbomachine,

[0026] [Fig. 2] Figure 2 is a larger-scale view of part of Figure 1.

[0027] [Fig. 3] Figure 3 is a larger-scale view of part of Figure 1 and shows the flow of oil through the reducer to the gutter,

[0028] [Fig. 4] Figure 4 is a view similar to that of Figure 3 and illustrates an alternative embodiment of the module, as well as the circulation of the oil in the reducer and a deflector up to the gutter,

[0029] [Fig. 5] Figure 5 is a view similar to that of Figure 3 and illustrates another embodiment of the module, as well as the circulation of the oil in the reducer and a deflector up to the gutter, and

[0030] [Fig.6] Figure 6 shows in a very schematic way several examples of making the gutter (in solid line) around the crown (in dashed line).

[0031] Detailed description of the invention

[0032] Figure 1 represents a module 10 according to the invention for an aircraft turbomachine.

[0033] A turbomachine typically comprises a gas generator consisting, from upstream to downstream with respect to the gas flow, of at least one compressor, an annular combustion chamber, and at least one turbine. The turbomachine may also comprise two sections, one low-pressure and one high-pressure, and thus include, from upstream to downstream, a low-pressure compressor, a high-pressure compressor, the combustion chamber, a high-pressure turbine, and a low-pressure turbine. The rotor of the low-pressure turbine is connected by the low-pressure shaft to the rotor of the low-pressure compressor.

[0034] The high-pressure turbine rotor is connected to the high-pressure compressor rotor by a high-pressure shaft. The high-pressure shaft is generally tubular and is traversed axially by the low-pressure shaft, which is also tubular.

[0035] The two shafts, low pressure and high pressure, are coaxial and therefore have the same axis of rotation, marked X in Figure 1. Figure 1 shows a portion of the low pressure shaft 12.

[0036] The low-pressure shaft 12 generally drives a propulsion propeller which may be located upstream of the gas generator. This propeller is called a blower and is surrounded by a nacelle that extends around the gas generator.

[0037] The propeller is connected to the shaft 12 via a reduction gear 14. The reduction gear 14 is part of the module 10 and it is understood that the reduction gear and the module are located rather upstream of the gas generator, and are for example surrounded by the low pressure compressor or by an inter-compressor housing 15 located between the low pressure and high pressure compressors.

[0038] The reducer 14 is of the planetary type and includes a solar 16 movable in rotation around the X axis, a ring 18 movable in rotation around the X axis and the solar 16, and satellites 20 meshed with the solar 16 and the ring 18 and carried by a satellite carrier 22.

[0039] The solar 16 has an annular shape and includes on its inner periphery splines 16a for coupling with complementary splines of the low pressure shaft 12.

[0040] In the example shown, the reducer 14 is of the two-stage type. Each of the satellites 20 comprises a first set of teeth 20a meshed with the teeth of the sun gear 16, and a second set of teeth 20b meshed with the teeth 18a of the ring gear 18.

[0041] The first set of teeth 20a comprises two annular rows of teeth located on either side of a median plane H perpendicular to the X-axis. The second set of teeth 20b comprises two annular rows of teeth also located on either side of the median plane H, as well as on either side of the first set of teeth 20a. The first set of teeth 20a is thus situated between the two rows of teeth of the second set of teeth 20b.

[0042] The dentition 18a of the crown 18 comprises two annular rows of teeth which are also located on either side of the median plane H, but also on either side of the first dentition 20a. The first dentition 20a is thus situated between the two rows of teeth of the dentition 18a. The rows of teeth of the dentition 18a mesh with the rows of teeth of the second dentition 20b.

[0043] In the example shown, each of the satellites 20 is tubular and is guided in rotation on a bearing 24, here a rolling bearing, which is carried by the satellite carrier 22. As seen in Figure 1, the reducer 14 is lubricated and includes a lubrication system which allows in particular the lubrication of the bearing 24 and the gears of the reducer 14. Alternatively, the bearing 24 could be plain.

[0044] In addition to the reducer 14, the module 10 according to the invention includes an annular stator housing 28 which extends around the X axis, and at least partly around the reducer 14.

[0045] The housing 28 may be located upstream of the aforementioned inter-compressor housing 15. The housing 28 may include at its downstream end an annular flange 28a for attachment to an annular flange 15a of the inter-compressor housing 15.

[0046] The planet carrier 22 is fixed to the housing 28 by means of an annular flange 60 which extends around the X-axis and the reducer 14 mostly or primarily downstream of the flange 30a. Mostly means that more than half of the length of the flange along the X-axis is located downstream of the flange 30a.

[0047] The flange 60 includes at a downstream end an annular flange 60a for fixing to the planet carrier 22 and at an upstream end another annular flange 60b for fixing to the housing 28. The flange 60b can be interposed between the flanges 28a, 15a of the housings 28, 12. The flange 60b can be located upstream of the flange 30a.

[0048] The module 10 further includes an annular crown carrier 30 which extends around the X axis and which is guided in rotation by bearings 32 inside the housing 28.

[0049] The crown carrier 30 includes at one downstream end an annular flange 30a for fixing to the crown 18. In the example shown, the crown 18 includes a radially external annular flange 34. The flange 30a can be applied against an upstream face of the flange 34 and fixed to this flange 34 by fastening elements 36 of the screw-nut type, for example.

[0050] The crown 18 can be formed from a single piece or by the assembly of two annular pieces. In the latter case, the flange 34 can be formed by two annular half-flanges belonging respectively to two half-crowns, a first annular flange being part of a first half-crown which includes one of the rows of teeth of the toothing 18a, and a second annular flange being part of a second half-crown which includes the other of the rows of teeth of the toothing 18a.

[0051] The crown carrier 30 can extend fully upstream of the flange 34 as in the example shown.

[0052] The crown carrier 30 can comprise three successive axial sections, an upstream section 38, an intermediate section 40 and a downstream section 42. The bearings 32, here with roller bearings, are mounted between the section 38 and the housing 28. The bearings 32 are here located upstream of the reducer 14 on a diameter smaller than the external diameter of the reducer 14.

[0053] Section 40 extends between sections 38 and 42. Section 40 is frustoconical and flares downstream. That is to say, its axial end with the smaller diameter is located upstream and connected to section 38, and its axial end with the larger diameter is located downstream and connected to section 42.

[0054] Section 42 extends between section 40 and flange 30a. Section 42 is preferably cylindrical.

[0055] The crown carrier 30, and in particular its section 42, extends around at least part of the crown 18 and defines with it a first annular space E1 more clearly visible in figure 2.

[0056] The ring 18 includes radial through-holes 44 which open radially outwards into this space E1. These holes 44 are located upstream of the flanges 30a, 34. In the example shown, the holes 44 are formed in a wall 46, preferably cylindrical, of the ring 18. This wall 46 surrounds the first toothing 20a of the planet gears 20.

[0057] The orifices 44 can be distributed, preferably regularly, around the X axis and form an annular row of orifices 44.

[0058] The crown carrier 30 includes radial through ports 48 which open radially inwards into space E1. These ports 48 are located upstream of flanges 30a, 34, and further upstream of ports 44.

[0059] In the example shown, the orifices 48 are formed in the section 42 which surrounds the wall 46.

[0060] The orifices 48 can be distributed, preferably regularly, around the X axis and form an annular row of orifices 48.

[0061] The module 10 according to the invention further comprises an annular gutter 50 which extends around the axis X and the crown carrier 30 and which is fixed to the housing 28.

[0062] The gutter 50 is located entirely upstream of the flange 30a of the crown carrier 30. The gutter 50 has an annular cavity 52 which opens radially inwards and which is located radially opposite orifices 48 of the crown carrier 30. In the example shown, the gutter 50 comprises a first part 50a which has an axial U-shaped form to define the annular cavity 52, and a second part 50b for connecting the first part 50a to the housing 28.

[0063] The first part 50a preferably has a maximum external diameter Dmaxl which is less than or equal to the maximum external diameter Dmax2 of the flange 30a.

[0064] The second part 50b may include an annular flange 54 for fixing to the housing 28 and an annular wall 56 for connecting the flange 54 to the first part 50a.

[0065] The annular wall 56 preferably has a maximum external diameter Dmax3 which is less than or equal to the maximum external diameter Dmax2 of the flange 30a.

[0066] The first and second parts 50a, 50b of the gutter 50 are preferably formed from a single piece.

[0067] Advantageously, the orifices 48 of the ring carrier 30 open into the middle of the cavity 52, as can be seen in Figure 2. Figure 3 shows the oil circulation in the gearbox 14 and the module 10. The oil in contact with the rotating parts of the gearbox 14 is centrifuged and expelled. Oil can be routed directly through the ring carrier 30 to space E1. Oil can also be routed inside the ring gear 18 and circulate through the orifices 44 into space E1.

[0068] The oil contained in space E1 then passes through the orifices 48 to enter and be collected in the gutter 50.

[0069] The gutter 50 is part of the stator of the module 10 and preferably surrounds the ring carrier 30 with a small radial clearance to prevent oil leakage between the gutter 50 and the ring carrier 30. The oil arrives in the gutter 50 with a certain tangential velocity and continues to rotate and flow in a circumferential direction around the X axis in contact with the gutter 50, to be conveyed to a lower part of the gutter 50, as will be described in more detail below with reference to Figure 6.

[0070] Figure 4 illustrates an alternative embodiment of module 10 which differs from the previous embodiment essentially in that it also includes an annular deflector 70.

[0071] The deflector 70 extends around the X axis and at least part of the reducer 14. The deflector 70 has at an upstream end an annular flange 70a for fixing to the flange 30a.

[0072] In the example shown, flange 70a is applied axially against a downstream face of flange 34 and fixed to this flange 34 by the aforementioned fastening elements 36. Flange 34 is thus axially interposed between flanges 30a and 70a.

[0073] The flange 34 of the crown 18 has axial through ports 72 for the passage of oil from the inside of the deflector 70 to the inside of the crown carrier 30.

[0074] The deflector 70 extends around at least part of the ring 18 and defines with it a second annular space E2, which is in fluidic communication via the orifices 72 with space E1. Figure 4 also shows the oil circulation in the reducer 14 and the module 10. In addition to the oil circulating as mentioned above with reference to Figure 3, oil will flow axially from space E2 to space E1. This oil is that collected by the deflector by oil spray from rotating parts of the reducer 14.

[0075] Figure 5 illustrates another embodiment of module 10, which differs from the embodiment in Figure 4 primarily in that the reduction gear 14 is a single-stage type rather than a double-stage type. This means that each of the satellite gears 20 comprises a single tooth 20a, and that the ring gear 18 also comprises a single tooth 18a. Therefore, the same tooth on each satellite gear 20 meshes with both the solar gear 16 and the tooth 18a of the ring gear 18.

[0076] Flange 54 of gutter 50 is here axially intercalated between flange 28a on the one hand, located upstream, and flanges 60b, 15a on the other hand located downstream.

[0077] The deflector 70 extends around at least part of the ring 18 and defines with it a second annular space E2 which is in fluidic communication through the orifices 72 with the space E1.

[0078] Figure 6 shows several possible configurations for gutter 50.

[0079] The inner circle in dashed line represents the crown 18, whether it is single or double tiered.

[0080] The outer circle in continuous or almost continuous line represents the gutter 50. The gutter 50 preferably extends over more than 340° around the X axis and includes at least one radially external oil outlet opening 80.

[0081] This opening 80 is preferably located between 5 and 7 o'clock, and preferably at 6 o'clock, by analogy with the face of a clock centered on the X-axis. This opening 80 can be chosen from a hole, a grid, a slot, etc. The edges of the opening 80 can be shaped to facilitate the flow and recovery of the oil.

[0082] Module 10 according to the invention offers several advantages, including: - it allows oil to be evacuated from a gearbox without passing through the ring gear flange,

[0083] - It allows for a reduced radial footprint compared to so-called "classic" oil evacuation solutions via the crown flange because the channel is positioned upstream of the flange and may not protrude beyond its external diameter; - The module allows for a "modular" mounting of the reducer, thus facilitating its assembly and disassembly.

[0084] - etc.

Claims

DEMANDS 1. Module (10) for an aircraft turbomachine, this module (10) comprising: an annular stator housing (28) extending about an axis (X), a planetary gearbox (14) mounted at least partially inside the housing (28), the gearbox (14) having a sun gear (16) rotatable about the axis (X), a ring gear (18) rotatable about the axis (X) and the sun gear (16), and planet gears (20) meshed with the sun gear (16) and the ring gear (18) and carried by a planet carrier (22) fixed to the housing (28), an annular ring carrier (30) extending about the axis (X) and guided in rotation by bearings (32) inside the housing (28), the ring carrier (30) having at a downstream end a first annular flange (30a) for attachment to the crown (18), and an annular gutter (50) which extends around the axis (X) and the crown carrier (30) and which is fixed to the casing (30),characterized in that the gutter (50) is located entirely upstream of the first flange (30a) of the crown carrier (30), and in that the gutter (50) has an annular cavity (52) which opens radially inwards and is located radially opposite first radial oil passages (48) formed in the crown carrier (30) upstream of said first flange (30a).

2. Module (10) according to claim 1, in which the gutter (50) comprises a first part (50a) which has in axial section a U-shaped form to define said annular cavity (52), and a second part (50b) for connecting the first part (50a) to the housing (28).

3. Module (10) according to claim 2, wherein the first part (50a) has a maximum external diameter (Dmaxl) which is less than or equal to the maximum external diameter (Dmax2) of said first flange (30a).

4. Module (10) according to claim 2 or 3, wherein the second part (50b) comprises a second annular flange (54) for fixing to the housing (28) and an annular wall (56) for connecting the second flange (54) to the first part (50a), this annular wall (56) having a maximum external diameter (Dmax3) which is less than or equal to the maximum external diameter (Dmax2) of said second flange (54).

5. Module (10) according to any one of claims 2 to 4, wherein the first and second parts (50a, 50b) are formed from a single piece.

6. Module (10) according to any one of the preceding claims, wherein the first orifices (48) are formed in a cylindrical part of the crown carrier (30), this cylindrical part extending for example between a frustoconical part and said first flange (30a) of the crown carrier (30).

7. Module (10) according to any one of the preceding claims, wherein the first orifices (48) open into the middle of said cavity (52).

8. Module (10) according to any one of the preceding claims, wherein the satellite carrier (22) is fixed to the housing (28) by means of an annular flange (60) which extends around the axis (X) and the reducer (14) downstream of said first flange (30a).

9. Module (10) according to claim 8, wherein the flange (60) comprises at a downstream end an annular flange (60a) for fixing to the planet carrier (22) and at an upstream end another annular flange (60b) for fixing to the housing (28), this other flange (60b) being located for example upstream of said first flange (30a).

10. Module (10) according to any one of the preceding claims, wherein the ring (18) comprises second radial through oil passage orifices (44).

11. Module (10) according to claim 10, wherein the second orifices (44) are located upstream of said first flange (30a), and preferably downstream of the first orifices (48).

12. Module (10) according to any one of the preceding claims, wherein it further comprises an annular deflector (70) extending around the axis (X) and at least a portion of the reducer (14), the deflector (70) having at an upstream end an annular flange (70a) for attachment to said first flange (30a).

13. Module (10) according to claim 12, wherein the crown (18) comprises a radially external annular flange (34) axially interposed between said first flange (30a) and the flange (70a) of the deflector (70), the flange (34) of the crown (18) having axial through ports (72) for the passage of oil from the inside of the deflector (70) to the inside of the crown carrier (30).

14. Module (10) according to any one of the preceding claims, wherein the gutter (50) extends over 340° around the axis (X) and includes at least one radially external oil outlet opening (80) which is located between 5 o'clock and 7 o'clock, and preferably at 6 o'clock, by analogy with the dial of a clock centered on the axis.

15. Aircraft turbomachine, comprising a module (10) according to any one of the preceding claims.

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