FR3090035A1 - DEVICE FOR DECOOLING AND SEALING A LUBRICATION ENCLOSURE OF A TURBOMACHINE - Google Patents

Abstract

Device for deoiling and sealing an enclosure (E1) for lubricating an aircraft turbomachine, characterized in that it comprises at least one annular lubrication enclosure (E1) delimited at least in part by at least one shaft ( 3) and at least one stator extending around the shaft, at least one lubricated bearing (10, 13, 14) being located in said enclosure, and at least one annular sealing means (17a, 39a, 39b) being provided between the stator and the shaft ,. Figure for the abstract: Figure 5

Description

Description

Title of the invention: DEVICE FOR DECOOLING AND SEALING A LUBRICATION ENCLOSURE OF A TURBOMACHINE

Technical field of the invention

The present invention relates in particular to a device for deoiling and sealing a lubrication enclosure for an aircraft turbomachine. Technical background

[0002] An aircraft turbomachine comprises structural casings and a set of stators and rotors. The turbomachine can comprise one or more bodies, such as a low pressure body or LP, and a high pressure body or HP for example.

The rotors of the turbomachine are supported by rolling bearings which are themselves hooked to the structural housings by means of bearing supports. These bearings are lubricated with oil to optimize their operation and dissipate the thermal energy produced.

To contain the oil, the bearings are enclosed in a closed enclosure called the lubrication enclosure. The enclosure is delimited by fixed walls (stator (s), structural housings, bearing supports) and mobile (s) rotor (s)). At the interface of walls movable with respect to each other, seals (for example at a labyrinth) are placed to contain the oil, and an air circuit pressurizes these seals to prevent oil leaks outside the enclosure.

The enclosure is thus pressurized (air enters continuously, repelling the oil which could have left the seals by capillary action or gravity) and the bearings operate in a medium of oil and mixed air forming a fog inside the enclosure. The bearings are supplied by an oil supply circuit and the oil recovery is ensured by a specific recovery circuit.

To avoid overpressure of the enclosure, and allow a constant flow of incoming air, the interior of the enclosure is connected to a medium of pressure lower than the pressure of the air entering the seals, it is degassing which consists in evacuating air from the enclosure. However, this oil-laden air is separated from its oil before its evacuation by deaerators or oil separators, the oil being intended to be recycled.

These air / oil separation members can be placed at different places in the oil circuit, and for example:

• at the borders of an enclosure; the energy necessary for oil removal is then supplied directly by the rotation of the bodies; the oil is returned to the enclosure and the air is discharged through a tube passing through the turbomachine to the outside;

• on the oil circuit; the energy required for oil removal is supplied by the auxiliary drive shaft and the oil returns to the oil tank in general.

[0008] In the case of deoiling on the oil circuit, the air exhaust tube passes through a structural casing to external equipment. In the case of oil removal at the borders of an enclosure, it passes through the entire engine, generally via the LP rotor, and discharges the treated air outside the engine. It is then called central degassing tube or centervent tube in English. These two solutions have advantages and disadvantages. The first solution is commonly used because it offers the advantage of being the simplest in installation and allows a gain in mass because the oil separator is integrated into the enclosure and no oiled air hose must be installed.

The pressurization air for the seals is taken from a vein of a compressor of the turbomachine. This air "consumed" to ensure the oil seal of the enclosure, is a pure loss from a motor thermodynamic point of view. It constrains both the sizing of the turbomachine and its overall performance. In addition, the means of conveying this air from the compressor to the enclosure have a significant mass and can be difficult to integrate into the turbomachine.

There is therefore a need to have an "active" seal which would dispense with pressurization and thus be able to reduce the air samples in the compressor to optimize the performance of the turbomachine.

Summary of the invention

The present invention provides a simple, effective and economical solution to the aforementioned problem of the prior art.

The invention provides a deoiling and sealing device for an lubrication enclosure for an aircraft turbomachine, characterized in that it comprises at least one annular lubrication enclosure delimited at least in part by at least one shaft and at least one stator extending around the shaft, at least one lubricated bearing being located in said enclosure, at least one annular sealing means being provided between the stator and the shaft,

Characterized in that, at the level of said at least one sealing means,

Said stator comprises an outer annular end portion comprising an annular row of radial through openings configured to force the centrifugal passage of air and oil through them,

Said shaft comprises an internal annular end part engaged in said external annular end part and comprising an annular row of through radial orifices configured to form an oil separator and force the centripetal passage of air through them, and

Said shaft comprises radially external sealing ring wipers located radially between said internal and external annular end portions, on either side of said openings and said orifices, and capable of allowing the axial passage of air in the axial space extending between said wipers and into which open said openings and said orifices.

The device according to the invention allows both to achieve the seal and the oil removal of the enclosure. Unlike the prior art, pressurizing air no longer passes through the rotor / stator seal towards the enclosure, but the degassing passes through it towards the outside of the enclosure. The device uses the speed of the shaft which delimits the enclosure, so that the drops of oil and the oil-laden air which comes from the enclosure penetrate into the aforementioned space, are centrifuged and reinjected into the enclosure through the openings, and that the deoiled air flows in a centripetal way through the orifices. These orifices have a function similar to oil separators, which are however used in the prior art in an enclosure remote from these sealing means. On the contrary, they are here integrated into the sealing means. The openings have an axial space decompression function to limit the degassing of the enclosure and reinject most of the oil-laden air from the enclosure to the enclosure.

The device according to the invention may include one or more of the following characteristics, taken in isolation from one another or in combination with each other:

- said openings define between them blades capable of forcing air circulation from said space towards said enclosure,

- said openings open onto an inner cylindrical surface of larger diameter of said outer annular end portion,

- said orifices are formed in an annular boss projecting from an external cylindrical surface of said internal annular end portion,

- an annular row of axial lunules extends between the wipers,

- said radially outer end portion comprises at least one radially inner annular collar which extends in said space, between said openings and one of said wipers,

- said radially internal and external parts are located at the level of said at least one sealing means, said flange being located upstream of said openings and downstream of one of said wipers,

- said flange extends upstream of said lunules and has an internal diameter less than or greater than the external diameter of said lunules,

- said flange is located between said openings and at least one radial drainage orifice formed in said radially external end,

- said internal annular end part defines a radially internal housing which is closed axially in a leaktight manner by a partition at a free end of this part,

- The device comprises rolling bearings located in said enclosure and comprising an upstream bearing mounted at an axial end upstream of the enclosure, between the stator and the shaft, and a second downstream bearing mounted at an axial downstream end of the enclosure, between the stator and the shaft, first annular sealing means being provided upstream of said first bearing, between the stator and the shaft, and second annular sealing means being provided downstream of said second bearing, between the stator and the shaft, characterized in that, at the level of said first and / or second sealing means.

The invention further relates to an aircraft turbomachine, comprising at least one device as described above.

The invention also relates to a process for deoiling an lubrication enclosure for an aircraft turbomachine, by means of a device as described above, in which:

- the lubrication enclosure of said at least one bearing is at a pressure PI,

- said space is at a pressure P2,

- said partition separates said housing in a sealed manner at a pressure P3 from a cavity at a pressure P4,

In which PI is greater than P2 which is greater than P3, and

In which P4 is greater than P2,

So that:

- a mixture of air and oil passes through said openings, from said space to said enclosure,

- air and / or oil passes axially through said sealing wipers, from said cavity and / or said enclosure, up to said space, and

- A mixture of air and oil passes through said orifices, from said space to said housing, for its deoiling.

PI and P4 can be identical.

Brief description of the figures

The invention will be better understood and other details, characteristics and advantages of the invention will appear on reading the following description given by way of non-limiting example and with reference to the accompanying drawings in which:

[Fig. 1] FIG. 1 is a schematic view in axial section of an aircraft turbomachine,

[Fig.2] Figure 2 is a schematic view on a larger scale of a part of a turbomachine,

[Fig-3] Figure 3 is another partial schematic view of a turbomachine degassing tube,

[Fig-4] FIG. 4 is a diagrammatic view on a larger scale of a part of a turbomachine,

[Fig.5] Figure 5 is a schematic view on a larger scale of a part of a turbomachine, and illustrates an embodiment of the device according to the invention,

[Fig.6] Figure 6 is a schematic perspective view with partial cutaway of one embodiment of the device according to the invention,

[Fig-7] FIG. 7 is a schematic sectional view of the embodiment of the device of FIG. 6,

[Fig.8] FIG. 8 is a view similar to FIG. 7 and illustrating a particular position of the turbomachine in operation, with the embodiment of the device of FIG. 5,

[Fig.9] Figure 9 is a view similar to that of Figure 6 and illustrates an alternative embodiment of the device according to the invention, and

[Fig.10] Figure 10 is a view similar to that of Figure 7 and illustrates the variant of Figure 9.

Detailed description of the invention

The invention can be applied to any type of turbomachine, whether or not fitted with a reduction gear.

The turbomachine 1 shown in Figure 1 is of the reducer type, which comprises, conventionally, a blower S, a low pressure compressor la, a high pressure compressor 1b, a combustion chamber le, a high pressure turbine Id and a low pressure turbine on. The rotors of the high pressure compressor 1b and the high pressure turbine Id are connected by a high pressure shaft 5 or HP. The rotors of the low pressure compressor 1a and of the low pressure turbine are connected by a low pressure shaft 4 or BP. The turbomachine is thus of the double-body type, HP and BP. The blower is, for its part, carried by a blower shaft 3 which is connected by a reduction gear 7 to the LP shaft 4.

The HP and BP shafts extend along an axis A which is the axis of rotation of the turbomachine 1. In the following description, the concepts of longitudinal or radial, and interior or exterior, are relative to this axis.

The turbomachine 1 comprises structural casings. The HP body is held by two structural casings: the inter-compressor casing and the inter-turbine casing, and the BP body is held by at least two structural casings: the intermediate casing 2 and the inter-turbine casing and / or the casing exhaust 6.

The intermediate casing 2 supports bearings of the BP turbine shaft 4 which are housed in a front or upstream enclosure denoted El. The exhaust casing 6 supports bearings of the BP turbine shaft 4 which are housed in a rear or downstream enclosure marked E2.

The enclosures are generally in part delimited by bearing supports.

The reducer 7 is here of the planetary gear type. Figure 2 very schematically shows the size of the reducer. The reduction gear 7 comprises an input shaft 8 extending upstream of the LP shaft 4 and which is guided by a downstream bearing 10 carrying this LP shaft. The torque at the output of this reduction gear 7 is transmitted to the fan shaft 3, by a conventional connection, known to those skilled in the art, such as for example a fixing of this fan shaft to the planet carrier s forming a shaft outlet 9 of the reducer, in the case of a planetary gear reducer. In the case of a planetary gearbox, the fan shaft would be driven by the crown. The reducer is placed inside the front lubrication enclosure El.

The enclosure El comprises fixed walls and movable walls. The fixed walls of the enclosure El comprise an internal wall of the stream of the primary flow, an upstream bearing support 11 and a downstream bearing support 12. The supports 11 and 12 extend towards the interior of the turbomachine and respectively carry the bearings 13, 14 and the bearing 10. They provide the structure between the casings and the fixed outer rings of the bearings. The movable walls of the enclosure El include the input shafts 8 and outlet 9. The bearings 10, 13, 14 are housed in the enclosure El. Seals 17a, 17b in the diagrams are provided between the fixed walls and mobile and are for example labyrinth seals, brush seals, segmented radial seals, etc.

The bearings 10, 13 and 14 and the reducer 7 are lubricated for their proper functioning. The oil is supplied by suitable means 16 such as nozzles, oil supply pipes, etc. The enclosure El is configured so that the air-oil mixture, which forms an oil mist inside the enclosure, is contained in the latter. Between the rotor and stator walls of the enclosure, for example here at the upstream and downstream ends of the enclosure, seals (such as labyrinths) are placed to contain the oil, and an air circuit pressurizes these seals to prevent oil leakage. The El enclosure is then pressurized (air continuously enters through the seals, repelling oil that could have come out of the seals by capillary action) and the bearings operate in a medium of oil and mixed air. The bearings are supplied by an oil supply tube or a nozzle and recovery is ensured by a specific recovery tube. To avoid overpressure of the enclosure El, and to allow a constant flow of incoming air, the interior of the enclosure is vented at a pressure lower than the pressure of the incoming air through the seals. This oil-laden air, which is discharged through a pressure well, must first be treated to recover almost all of the oil it carries. For this, the oiled air will be brought to an oil separator which will separate the air from the oil it carries and will reject the oiled air outside the engine. This is the principle of removing oil from an enclosure.

The venting of the enclosure is carried out by a degassing tube 20 (FIG. 3) which passes axially through the BP turbine shaft 4, from the upstream enclosure El to the ejection cone 6a of the turbomachine.

The oil removal device generally comprises an annular row of oil removal tubes 21 which radially pass through the fan shaft 3 and allow the passage of oiled air radially from the outside to the inside, from the enclosure El up to a housing L arranged upstream of the degassing tube 20 (arrow 18). These tubes generate a free vortex by printing the speed of rotation of the blower shaft with oiled air which increases as it approaches the motor axis and the oil is centrifuged on the internal walls of the shaft. blower shaft 3 to return to the enclosure El (arrows 19).

Figure 3 illustrates a degassing tube 20 which can be used in the context of the invention.

The degassing tube 20 is produced in several sections in the example shown and comprises an upstream section 20a, an intermediate section 20b and a downstream section 20c. The sections are coaxial and extend one behind the other, their opposite axial ends being nested one inside the other.

The upstream section 20a is configured to be secured to the BP turbine shaft and comprises independent sealing means intended to cooperate with the input shaft 8 of the reduction gear 7. These sealing means are not visible and are for example formed by an annular seal. These sealing means, visible in FIG. 2, are crossed by air (arrow 33) which is added to the air (arrows 17) passing through the seals in order to pressurize the enclosure and avoid leaks of oil.

A disc, visible in Figure 2 in the form of a radial partition 15 closes the upstream end of the shaft 3. This radial partition 15 separates the cavity R located upstream and which is in operation at a pressure denoted P4, of the housing L located downstream and which is in operation at a pressure denoted P3. The cavity R is substantially cylindrical and delimited externally by the fan disk 3b and / or the inlet cone 3c, and the housing L is cylindrical and delimited externally by the shaft 3.

FIGS. 4 and 5 schematically represent the general concept of the invention which consists in setting up a specific device at at least one of the ends of the enclosure El, this device fulfilling a double sealing function and deoiling. Figures 4 and 5 illustrate an example of integration of this device at the upstream axial end of the enclosure El but such a device could also be mounted at the axial downstream end of the enclosure.

The shaft 3 comprises an internal annular end portion 3a which comprises an annular row of radial through holes 35 configured to impart a tangential speed to the air and to allow the centripetal passage of deoiled air (arrow Fl ). This deoiled air continues its way from upstream to downstream in the various sections of the tube 20 to be ejected into the atmosphere at the downstream end of the turbomachine.

An annular cover 40 extends upstream of the bearing support 11 and is fixed to this bearing support 11. This cover 40 has a generally frustoconical shape which is flared axially downstream. Its upstream axial end 40a of smaller diameter extends around the shaft 3, just upstream of the bearing 14, and its downstream end of larger diameter extends around the bearing 13 and is fixed to the intermediate casing 2. This cover 40 is part of a stator of the turbomachine and delimits part of the enclosure EL

The cover 40 comprises at its end 40a an external annular end part 40aa which surrounds the part 3a and which has an annular row of radial through openings 37 configured to cause the centrifugal passage of oil and oiled air (arrow F2). As seen in the example shown, the openings 37 and the orifices 35 are located in the enclosure El and substantially in the same transverse plane P.

Parts 3a and 40aa define between them an annular space E3 into which the radially internal ends of the openings 37 open and the radially external ends of the orifices 35. The space E3 is intended to be in operation at a pressure P2. This space E3 is delimited axially, upstream, by a first annular wiper 39a which is integral with part 3a and cooperates in sealing by labyrinth effect with part 40aa, and downstream, a second annular wiper 39b which is integral with part 3a and cooperates in sealing by labyrinth effect with part 40aa. The tops of the wipers 39a, 39b can cooperate with abradable annular coatings 44 provided on the part 40aa, as is better visible in FIG. 7. In these figures, the reference 31 designates oil droplets. The arrow F3 designates the flow of oiled air through the wiper 39b, between the enclosure El and the space E3, and the arrow F4 designates the air flow through the wiper 39a, from the cavity R to 'to space E3.

The openings 37 advantageously define between them blades 39 causing the centrifugal flow of the oiled air and the oil (Figures 6 and 9). The blades 39 each have a lower surface and an upper surface which are connected by a radially internal leading edge and by a radially external trailing edge.

These openings 37 provide a scoop function to the part 40aa which makes it possible to create a depression in the space E3. The device functions as a pump which aims to compensate for the loss of pressure of the air which passes through the wipers 39a,

39b, to allow at least partial reintroduction of the leakage rate into the enclosure El.

In addition to the centrifugal effect of the fluid, the scoop operates thanks to the tangential speed differential between the blades 39 and the air in space E3. The air in this space E3 is in contact with the shaft 3. If the tangential speed of the shaft 3 is insufficient, lunules 41 for rotating the air in the space E3 can be provided on the surface external annular IF of the part 3a of the shaft 3. These lunulas 41 extend axially over the entire length of the space E3, or over part of this space, between the wipers 39a, 39b. They can be formed by ribs or grooves extending between the wipers 39a, 39b. In the example shown, they extend more exactly between the wipers and an annular boss 43 projecting from the external surface SI of the part 3a, in which the orifices 35 are formed.

The lunulas 41 make it possible to bring the tangential speed of the oiled air into the space E3 close to the peripheral speed of the shaft 3. This arrangement makes it possible to operate the pump more efficiently (reduction in size) or increased pressure differential).

The blades 39 are therefore configured to allow the recompression of the fluid. These blades 39 have a setting adapted to the incident air direction. This setting is adapted to the direction of rotation of the shaft 3. A skilled person will be able to determine the characteristics of these blades according to the desired properties and performance.

In operation, the pressure PI in the enclosure El is greater than the pressure P2 in the space E3 which is greater than the pressure P3 in the housing L. The pressure P4 in the cavity R is greater than the pressure P2 . The space E3 is thus depressurized and the air which is contained in the cavity R and in the enclosure El, which are at a higher pressure, penetrates by the sealing wipers 39a, 39b as illustrated by the arrows F3 and F4. The oiled air contained in the enclosure El thus leaks through the downstream wiper 39b by pressure effect towards the axial space E3. In addition, the sealing of this wiper 39b is not perfect, which can result in a high air flow to be treated. The scoop 37 installed on the shaft 3 allows most of this air to be reinjected into the enclosure El via the increase in its pressure (arrow F2). The reinjected air is thus represented as safe.

The oiled air contained in space E3 is set in motion and the oil tends to separate from the air by centrifugation. Centrifuging the oiled air by rotating it directs most of the oil to the scoop. The oil then accumulates on the radially internal annular surface S2 of the part 3a which advantageously has a shape adapted to facilitate the flow of this oil to the openings 37. In the example shown, the surface S2 is biconic and the junction plane of the large bases of the two cones delimits the largest internal diameter of the part 40aa. This larger diameter is here located in the plane P in which the openings 37 are located. The oil 31 can then flow from the surface S2 into the openings 37 due to centrifugal forces. The air always loaded with oil, heavier than the deoiled air, also passes through the openings 37 and is then repressurized when it enters the EL enclosure. The deoiled air tends to reach the housing L which is at a pressure P3 lower than that P2 in the axial space E3. This pressure condition can be facilitated by using a jet pump in the housing L. The jet pump is preferably located downstream of the degassing tube at the exhaust casing. The air is sucked in the orifices 35 which can each receive a deoiling tube as illustrated in FIGS. 5 to 10. The deoiled air is then evacuated by the degassing tube 20 described in the foregoing. The unoiled air from the cavity R enters the space E3 through the upstream wiper 39a and discharges the oil in order to avoid any leakage outside the enclosure El (arrow F4). This pressurization air does not necessarily need to be of a pressure higher than that of the enclosure El (we can have P4 = PI = Pamb (ambient pressure)> P2) so that the impact of the leak on the performance is poor, even in case of severe misalignment. The leak mentioned here is the pressurization leak from the El enclosure overall. Each seal of the enclosure is pressurized by maintaining an incoming pressurizing air stream. If the venting of the enclosure is too high, it may be necessary to provide a high flow of pressurization air in front of each seal, which can adversely affect the performance of the turbomachine, since this air is generally taken from a compressor of the turbomachine. This sealing or deoiling works even in the event of a small pressure difference between El, R, E3 and L because a pressure difference is maintained thanks to the openings 37 and recirculation takes place if too much air arrives from the enclosure, c that is to say if the sealing of the wipers 39b between El and E3 allows too much air to pass.

In a variant not shown, the number of wipers 39a, 39b could be increased to adjust the leakage rates to an optimum. Other types of sealing (slave seals, fluid sealing) can be considered if better performance is required.

FIG. 8 illustrates an alternative embodiment of the device which differs from the previous embodiment in that the part 40aa comprises a radially internal annular flange 50 which extends in the radial direction upstream from the openings 37 and downstream from the upstream wiper 39a, and for example upstream of the lunules 4L

The flange 50 has in section a profile similar to that of a wiper 39a, 39b and therefore has a profile substantially pointed. It thus has an enlarged base connected to the part 40aa and a pointed apex oriented towards the part 3a of the shaft 3. An axial subspace E4 extends between the upstream wiper 39a and the flange 50. The flange 50 a advantageously an anti-overflow function, as will be explained in the following.

The flange 50 has an internal diameter which is here less than the external diameter of the lunula 41.

The part 40aa preferably comprises at least one radial orifice 52 for oil drainage and therefore for the passage of oil from the inside radially towards the outside. This orifice 52 opens here in the subspace E4. This oil is discharged from the enclosure by flowing through at least one pipe 54 extending from the orifice 52, along the cover 40, and up to the intermediate casing 2.

The drainage port 52 as well as the pipe 54 are preferably located at 6 o'clock, by analogy with the dial of a clock, that is to say in the lower part of the turbomachine. It is thus understood that the oil which reaches the subspace E4 can be recovered by gravity in the orifice 52 and the pipe 54.

Under certain flight attitudes or load factors, the oil recovery can be disturbed. The oil level can then rise in the enclosure El, until it reaches the seals and threatens the confinement of the oil in the enclosure. Once the wiper 39b is reached by the oil level, the confinement is no longer ensured and the oil can penetrate into the subspace E4 which allows the evacuation of the oil.

In these particular flight attitudes, the turbomachine can be inclined relative to the horizontal, the oil H can penetrate into the subspace E4, either by having submerged the first seal or by passing through the openings 37, as shown in FIG. 8. In these two cases, the oil level in the space E3 increases up to the lunula 41 without reaching the wiper 39a thanks to the anti-overflow collar 50 which forms a baffle. Once the lunules 41 are reached, the oil H is centrifuged and then reinjected into the enclosure El via the openings 37. Thus, the oil is actively pushed back towards the enclosure El so that no massive leak is to be expected . In the event that oil flows past the flange 50, into the subspace E4, this oil will flow into the pipe 52.

Figures 9 and 10 show another embodiment of the device according to the invention, which differs from the previous embodiment essentially in that the upstream wiper 39a is located on a cylindrical surface S3 whose diameter is less than that of the cylindrical surface SI on which the lunules 41 are located as well as the other wiper 39b. The upstream wiper 39a is located opposite a cylindrical surface S4 whose diameter is less than that of the cylindrical surface S5 on which the flange 50 is located, the latter diameter being greater than the diameter of the aforementioned surface SI. The collar 50 has an internal diameter which is here greater than the external diameter of the surface SI or even of the lunula 41. Furthermore, the diameter of the surface S4 is greater than that of the surface SI. This variant makes it easier to mount part 3a in part 40aa, by simple axial translation.

Claims (1)

Claims [Claim 1] Device for deoiling and sealing an enclosure (El) for lubricating an aircraft turbomachine, characterized in that it comprises at least one annular lubrication enclosure (El) delimited at least in part by at least one shaft ( 3) and at least one stator extending around the shaft, at least one lubricated bearing (10, 13, 14) being located in said enclosure, at least one annular sealing means (17a, 39a, 39b) being provided between the stator and the shaft, characterized in that, at said at least one sealing means, said stator (40) has an external annular end portion (40aa) comprising an annular row of radial openings ( 37) through configured to force the centrifugal passage of air and oil through them, said shaft (3) has an inner annular end portion (3a) engaged in said outer annular end portion (40aa) and having an annular row of through radial orifices (35) configured to form a d oil separator and force the centripetal passage of air through them, and said shaft comprises annular sealing wipers (39a, 39b) radially external located radially between said internal and external annular end portions (3a, 40aa) and other of said openings (37) and said orifices (35), and capable of allowing the axial passage of air in the axial space (E3) extending between said wipers and into which open said openings and said orifices. [Claim 2] Device according to claim 1, in which said openings (37) define between them blades (39) capable of forcing air circulation from said space (E3) towards said enclosure (El). [Claim 3] Device according to claim 1 or 2, wherein said openings (37) open onto an inner cylindrical surface (S2) of larger diameter of said outer annular end portion (40aa). [Claim 4] Device according to one of the preceding claims, in which said orifices (35) are formed in an annular boss (43) projecting from an external cylindrical surface (SI) of said internal annular end part (3a). [Claim 5] Device according to one of the preceding claims, in which an annular row of axial lunules (41) extends between the wipers (39a, 39b). [Claim 6] Device according to one of the preceding claims, in which said radially external end part (40aa) comprises at least one radially internal annular collar (50) which extends in said space (E3), between said openings (37) and one of said wipers (39a, 39b). [Claim 7] Device according to the preceding claim, in which said radially internal and external parts (3a, 40aa) are located at the level of said at least one sealing means (17a), said flange (50) being located upstream of said openings (37) and downstream of one (39a) of said wipers. [Claim 8] Device according to claim 6 or 7, wherein said flange (50) extends upstream of said lunules (41) and has an internal diameter less than or greater than the external diameter of said lunules. [Claim 9] Device according to one of Claims 6 to 8, in which said flange (50) is located between said openings (37) and at least one radial drainage orifice (52) formed in said radially external end part (40aa). [Claim 10] Device according to one of the preceding claims, in which said internal annular end part (3a) defines a radially internal housing (L) which is axially sealed by a partition (15) at a free end of this part. [Claim 11] Aircraft turbomachine, in particular with a reduction gear, comprising at least one device according to one of the preceding claims. [Claim 12] Method for deoiling an lubrication enclosure for an aircraft turbomachine, by means of a device according to claim 10, in which: - the lubrication enclosure (El) of said at least one bearing is at a pressure PI, - said space (E3) is at a pressure P2, - said partition (23) sealingly separates said housing (L) at a pressure P3 from a cavity (R) at a pressure P4, in which PI is greater than P2 which is greater than P3, and in which P4 is greater than P2, so that: - a mixture of air and oil passes through said openings (37), from said space to said enclosure, - air and / or oil passes axially through said sealing wipers (39a, 39b), from said cavity and / or said enclosure, up to said space, and - A mixture of air and oil passes through said orifices (35), from said space to said housing, for its deoiling.