Turbomachine including a variable damping shaft bearing damper

Abstract

Turbomachine comprising a variable damping shaft bearing damper, having a rotating shaft (16), a bearing (18) supporting the rotating shaft (16), a bearing support (20) supporting the bearing (18), and an intermediate ring (24) disposed between the bearing (18) and the bearing support (20), the intermediate ring (24) being configured to slide axially relative to the bearing (18), a first sealing segment (36) axially coupled with the bearing (18) and a second sealing segment (38) axially coupled with the intermediate ring (24), the first sealing segment (36), the second sealing segment (38), the bearing (18) and the intermediate ring (24) defining a chamber (40) of variable axial length (L) and forming, when filled with oil, a variable damping film,in which a return device (60) exerts an elastic return force (E) configured to return the intermediate ring (24) to a predetermined axial rest position relative to the bearing (18). Fig. 2,

Description

Title of the invention: Turbomachine comprising a variable damping shaft bearing damper Technical field

[0001] The present disclosure relates to a turbomachine comprising a variable damping shaft bearing damper.

[0002] The term "turbomachine" refers to all gas turbine devices producing motive power, among which we distinguish in particular turbojets providing the thrust necessary for propulsion by reaction to the high-speed ejection of hot gases, and turboshafts in which the motive power is provided by the rotation of a drive shaft. For example, turboshafts are used as engines for helicopters, ships, trains, or even as industrial engines. Turboprops (turboshafts driving a propeller) are also turboshafts used as aircraft engines. Prior art

[0003] Various turbomachine shaft bearing dampers are known, for example from EP 2 753 844 or FR 2 629 537. However, these dampers are more or less effective depending on the operating range of the turbomachine.

[0004] FR 3 096 072 is also known, which proposes modifying the damping of a bearing damper by modifying the length of a damping oil film using an actuator which axially moves an intermediate ring.

[0005] However, although this configuration effectively allows the damping to be adapted to the operating range of the turbomachine, it requires active control which makes it quite complex to implement.

[0006] There is therefore a real need for a variable damping shaft bearing damper which is free, at least in part, from the drawbacks inherent in the aforementioned known configuration. Statement of the invention

[0007] The present disclosure relates to a turbomachine extending in an axial direction and in a radial direction, comprising at least one rotary shaft, at least one bearing, supporting the rotary shaft, a bearing support, supporting the bearing, a spring element, mechanically connecting the bearing support and the bearing, an intermediate ring, arranged radially between the bearing and the bearing support, the intermediate ring being configured to slide axially relative to the bearing, a first sealing segment, arranged radially between the bearing and the intermediate ring and axially coupled with the bearing, a second sealing segment, arranged radially between the bearing and the intermediate ring and axially coupled with the intermediate ring, wherein the first sealing segment, the second sealing segment, the bearing and the intermediate ring define a chamber configured to receive oil, the axial length of the chamber being variable depending on the axial position of the intermediate ring relative to the bearing, thus forming, when filled with oil, a variable damping film, wherein a return device exerts an elastic return force configured to return the intermediate ring to a predetermined axial rest position relative to the bearing.

[0008] Generally speaking, the axial direction corresponds to the direction of the axis of the turbomachine shaft, and a radial direction is a direction perpendicular to the axial direction. The azimuthal direction corresponds to the direction describing a ring around the axial direction. The three directions axial, radial and azimuthal correspond respectively to the directions defined by the coast, the radius and the angle in a cylindrical coordinate system. Finally, unless otherwise specified, the adjectives inner and outer (or internal and external) are used in reference to a radial direction so that the inner part (i.e. radially inner) of an element is closer to the axis of the shaft than the outer part (i.e. radially outer) of the same element.

[0009] It is understood that the intermediate ring is configured to slide in the axial direction whereby the axial length of the chamber varies. Indeed, the first sealing segment is axially coupled to the bearing while the second sealing segment is axially coupled with the intermediate ring. Thus, by axially moving the intermediate ring relative to the bearing, the first sealing segment is axially moved relative to the second sealing segment. Thus, the chamber being delimited radially by the bearing on the one hand and by the intermediate ring on the other hand, and axially by the first sealing segment on the one hand and by the second sealing segment on the other hand, by axially moving the intermediate ring relative to the bearing, the axial length separating the first sealing segment and the second sealing segment is modified, and therefore the axial length of the chamber.

[0010] The inventors have found that in operation, by varying the axial length of the chamber, the volume of oil working in the chamber is varied, and therefore the damping thus produced (viscosity). The damping can therefore be adapted according to the speed of the turbomachine, and therefore this system can be made effective over the entire the speed range of the turbomachine. In other words, the state-of-the-art damping devices can only effectively damp one natural mode of shaft vibration, whereas by varying the viscosity, several distinct natural modes of rotor vibration can be damped.

[0011] Furthermore, in the proposed configuration, the position of the intermediate ring, and therefore the viscosity of the damper, automatically results from the pressure of the oil in the chamber. Indeed, at low pressure, when the turbomachine is running at low speed, the return device returns the intermediate ring to its rest position; then, when the turbomachine is running at high speed and the oil pressure then increases, the resultant of the pressure forces exerted by the damping oil on the intermediate ring tends to oppose and then exceed the elastic return force of the return device, then leading to axially moving the intermediate ring away from the axial rest position.

[0012] It is then possible to adjust the geometric parameters of the bearing, the intermediate ring and the spring so as to adjust the volume of the chamber, and therefore its damping, according to the operating range of the turbomachine.

[0013] In particular, this configuration allows such adjustment passively and automatically, without having to resort to an actuator to move the intermediate ring.

[0014] In some embodiments, the intermediate ring is configured to be displaced axially relative to the bearing, against the elastic return force of the return device, under the effect of the pressure of the damping oil present in the chamber.

[0015] In some embodiments, the intermediate ring is devoid of any active actuator.

[0016] In certain embodiments, the return device is a leaf spring disposed between the intermediate ring on the one hand and the bearing or bearing support on the other hand.

[0017] In some embodiments, a first end of the leaf spring is embedded in the bearing or bearing support and a second end of the leaf spring bears against a shoulder of the intermediate ring.

[0018] In certain embodiments, the return device is a compression spring, for example a helical spring, placed in compression between the intermediate ring on the one hand and the bearing or the bearing support on the other hand.

[0019] In some embodiments, the compression spring is received in a notch of the intermediate ring between a shoulder of said notch and a projection of the bearing or bearing support engaging in said notch.

[0020] In some embodiments, the first segment is received in an annular groove formed in an outer surface of the bearing. Such a configuration allows to ensure reliable and efficient axial coupling of the first sealing segment. For example, the first sealing segment also cooperates with a uniform portion of the inner surface of the intermediate ring.

[0021] In certain embodiments, an external surface of the bearing comprises a recess, in which the second sealing segment is positioned, locally widening the chamber so as to form a first cavity whose volume is variable depending on the axial position of the intermediate ring relative to the bearing. Such a cavity having a greater thickness makes it possible, on the one hand, to increase the resultant of the pressure forces of the oil exerted on the second sealing segment and therefore on the intermediate ring, facilitating the maneuvering of the latter. On the other hand, it is thus possible to increase more quickly the volume of damping oil in the chamber depending on the movement of the intermediate ring, which makes it possible to adjust the viscosity of the damper over a wide range while preserving the compactness of the assembly.

[0022] In some embodiments, the intermediate ring has an internal projection extending radially inwardly so as to be positioned in the recess of the external surface of the bearing.

[0023] In some embodiments, the second sealing segment is mounted against a shoulder formed by the internal projection of the intermediate ring.

[0024] In some embodiments, the bearing support comprises a recess, in which the intermediate ring comprises an external projection extending radially outwardly so as to be positioned in the recess of the bearing support, in which the recess of the bearing support and the external projection of the intermediate ring form a second cavity, configured to receive damping oil, the volume of which is variable depending on the axial position of the intermediate ring relative to the bearing. This second cavity makes it possible to increase the resultant of the pressure forces of the oil exerted on the intermediate ring, facilitating the maneuvering of the latter. On the other hand, this second cavity is not necessarily part of the chamber and therefore does not necessarily contribute to the damping of the bearing.

[0025] In some embodiments, the end of the outer projection is flush against the inner surface of the bearing support, and a sealing segment may be disposed at the end of the outer projection.

[0026] In some embodiments, the bearing support comprises a first oil circuit connecting an oil inlet to the chamber. This first oil circuit makes it possible to supply the chamber with oil. The flow rate supplied and therefore the pressure of the oil present in the chamber may depend on the speed of the turbomachine, in particular be proportional to the rotation speed of one of its organs.

[0027] In some embodiments, the bearing support comprises a second oil circuit connecting the oil inlet to the second cavity. This second oil circuit makes it possible to supply the second cavity with oil. This second circuit can branch off from the first circuit. A valve or a flow reducer can be arranged on this second circuit.

[0028] In certain embodiments, the turbomachine comprises a first axial stop configured to axially block the intermediate ring relative to the bearing in said predetermined axial rest position of the intermediate ring.

[0029] In certain embodiments, the first axial stop is arranged on an external surface of the bearing. Such a location makes it possible to limit the overall size.

[0030] In some embodiments, the first axial stop has a conical profile, and wherein the intermediate ring comprises a stop surface configured to bear on the first axial stop, said stop surface having a conical profile coinciding with the conical profile of the first axial stop. Thanks to this configuration, when the turbomachine is rotating at low speed, and therefore the intermediate ring is in its axial rest position, or in a position close to this axial rest position, the conical profile of the stop surface of the intermediate ring cooperates with the conical profile of the first axial stop, which tends to reduce or even completely block the radial position of the intermediate ring.Thus, at low speed, when the damping oil pressure is insufficient to prevent contact, the cooperation of these conical profiles makes it possible to block the radial excursions of the intermediate ring and therefore the wear of the system by friction; moreover this makes it possible to block the ring to cancel the damping effect of the oil film as well as the flexibility induced by the spring element, which may be desirable at low speed to take advantage of a more favorable modal situation of the rotor.

[0031] In certain embodiments, the turbomachine comprises a second axial stop configured to axially block the intermediate ring relative to the bearing in a predetermined axial stop position of the intermediate ring relative to the bearing, in the direction opposite to the return force of the return device.

[0032] In some embodiments, the second axial stop extends from the outer surface of the bearing so as to receive support from the inner projection of the intermediate ring when it is in its predetermined axial stop position.

[0033] In some embodiments, the bearing support and the intermediate ring cooperate via an axially extending sliding connection. Such a sliding connection makes it possible to vary the axial distance between the sealing segments and therefore the active length of the oil film.

[0034] In some embodiments, the spring element is a variable stiffness spring element. The combination of a variable stiffness spring element and the variable damper makes it possible to dampen an even greater range of natural modes of the shaft / a wider range of speeds of the turbomachine. An example of a variable stiffness spring element is described in document FR 17 62885.

[0035] The above-mentioned features and advantages, as well as others, will become apparent upon reading the following detailed description of exemplary embodiments of the proposed turbomachine. This detailed description refers to the attached drawings. Brief description of the drawings

[0036] The object of the present disclosure and its advantages will be better understood upon reading the detailed description given below of different embodiments given as non-limiting examples.

[0037] In these drawings, from one figure to another, identical elements (or parts of elements) are identified by the same reference signs. In addition, elements (or parts of elements) belonging to different embodiments but having a similar function are identified in the figures by numerical references incremented by 100, 200, etc.

[0038] [Fig.l] [Fig.l] is a schematic sectional view of a turbomachine.

[0039] [Fig.2] [Fig.2] represents a first example of a bearing, in a first state.

[0040] [Fig.3] [Fig.3] represents the first example of a bearing, in a second state.

[0041] [Fig.4] [Fig.4] represents a second example of a bearing.

[0042] [Fig.5] [Fig.5] represents a third example of a bearing.

[0043] [Fig.6] [Fig.6] represents a fourth example of a bearing. Description of the embodiments

[0044] [Fig. 1] schematically illustrates a turbomachine 10, in this example a gas turbine engine, and more specifically a double-flow turbojet ("turbofan" in English). The turbomachine 10 extends in an axial direction X, a radial direction R and a circumferential or azimuthal direction C. The turbomachine 10 comprises a fan 11, a compressor 12, a combustion chamber 13, a first turbine 14, and a second turbine 15, arranged successively in the direction of flow M of the air and combustion gases therethrough. However, the teaching of the present disclosure is also applicable to other types of gas turbine engines, such as single-flow turbojets ("turbofan" in English), turboprops, or turboshafts, as well as to other types of turbomachines and rotating machines.

[0045] In the turbomachine 10, the fan 11 is coupled in rotation to the second turbine 15, and the compressor 12 to the first turbine 14 by, respectively, first and second coaxial rotary shafts 16, 17. These coaxial rotary shafts 16, 17 are supported in a casing 19 of the turbomachine 10 by corresponding bearings 18.

[0046] A first example of the structure of the turbomachine around the bearings 18 is described with reference to FIGS. 2 and 3. This description refers to the structure around only one of the bearings 18, but is applicable to all the bearings 18.

[0047] The bearing 18 shown in Figures 2 and 3 supports the shaft 16. The bearing 18 is supported by a bearing support 20. An annular spring element 22 mechanically connects the bearing 18 and the bearing support 20. An intermediate ring 24 is arranged radially between the bearing 18 and the bearing support 20.

[0048] The bearing 18 is in this example a ball bearing, and comprises an inner ring 18A which supports the shaft 16, an outer ring 18B and balls 18C provided between the inner ring 18A and the outer ring 18B. The outer ring 18B is mounted on a bearing ring 18D which is mechanically connected to the bearing support 20 via the spring element 22. In this example, the bearing ring 18D and the spring element 22 form a single piece, fixed on the bearing support 20.

[0049] In this example, the spring element 22 is a spring element with fixed stiffness. More specifically, in this example, the spring element 22 comprises a flexible cage having a first elastically flexible member 22A extending in the axial direction X. This first member 22A has a first axial end 22A1 connected to the bearing 18, and more specifically to the bearing ring 18D, and a second axial end 22A2. The flexible cage also has a second elastically flexible member 22B extending in the axial direction X. This second member 22B has a first end 22B1 connected to the bearing support 20 and a second end 22B2 connected to the second end 22A2 of the first member 22A. Thus, a radial force F can be transmitted between the bearing 18 and the bearing support 20 by bending of the first and second elastically flexible members 22A, 22B.

[0050] The bearing ring 18D comprises a main portion 18D1, against which the outer ring 18B of the bearing 18 is mounted, and a lateral portion 18D2. This lateral portion 18D2 has a thickness less than that of the main portion 18D1 such that the external surface 19E of the bearing ring 18D has a recess 19A forming a shoulder 19B at the interface between the main portion 18D1 and the lateral portion 18D2.

[0051] The intermediate ring 24 is arranged radially between the bearing support 20 and the bearing 18, more particularly the bearing ring 18D of the bearing 18, and is configured to slide axially relative to the bearing 18. The outer surface 25E of the intermediate ring 24 cooperates with the inner surface 211 of the bearing support 20 while the inner surface 251 of the intermediate ring 24 cooperates with the outer surface 19E of the bearing ring 18D. More precisely, the intermediate ring 24 cooperates with the bearing support 20 via a sliding connection extending axially, for example using a system of axial grooves / ribs engaged with each other.

[0052] The intermediate ring 24 comprises, at a first axial end 24F, a collar 51 extending radially outward so as to form a shoulder 51A. The intermediate ring 24 comprises, at a second axial end 24G opposite the first axial end 24F, a collar 52, forming an internal projection, extending radially inward so as to form a shoulder 52A. The internal end of the collar 52 is positioned in the recess 19A of the bearing ring 18D and therefore protrudes partly opposite the shoulder 19B of the bearing ring 18D.

[0053] The intermediate ring 24 cooperates with the bearing ring 18D by means of a first sealing segment 36 and a second sealing segment 38. The first sealing segment 36 is received in an annular groove 18D3 formed in the external surface 19E of the bearing 18, whereby it is axially coupled with the bearing 18. The second sealing segment 38 is mounted against the shoulder 52A formed by the collar 52, whereby it is axially coupled with the intermediate ring 24. Thus, the first sealing segment 36, the second sealing segment 38, the intermediate ring 24, and more particularly in this example the internal surface 251 of the intermediate ring 24, and the bearing 18, and more particularly in this example the external surface 19E of the bearing ring 18D of the bearing 18, form a chamber 40.The intermediate ring 24 being axially movable relative to the bearing 18, the first sealing segment 36 being axially coupled to the bearing 18 while the second sealing segment 38 is coupled to the intermediate ring 24, the axial length L of the chamber 40 varies as a function of the relative axial position of the intermediate ring 24 relative to the bearing 18.

[0054] The chamber 40 has an oil supply orifice 24C formed in the intermediate ring 24. It is noted that an oil accumulation chamber 42 is formed between the intermediate ring 24 and the bearing support 20. This chamber 42 makes it possible to form an accumulation of oil to supply the chamber 40 via the orifice 24C (which in this example fluidly connects the chamber 40 and the chamber 42). The chamber 42 is supplied with oil by means known elsewhere via a supply channel 20A. Thus, in operation, the oil follows the flow represented by the broken lines in [Fig.2].

[0055] The bearing ring 20D has an axial stop 18E configured to cooperate axially with the first axial end 24F of the intermediate ring 24.

[0056] An elastic return device 60 is installed so as to axially push the intermediate ring 24 in a direction bringing the sealing segments 36, 38 closer to each other and therefore reducing the length L of the chamber 40, i.e. to the left in [Fig. 2]. In the present example, the elastic return device is a leaf spring 60, a first end of which is embedded in the second member 22B of the spring element 22, at its end 22B1 fixed to the bearing support 20, and the second end of which bears against the shoulder 51A formed by the collar 51 of the intermediate ring 24.

[0057] In the absence of significant pressure in the chamber 40, as shown in [Fig. 2], the spring 60 exerts a return force E which returns the intermediate ring 40 towards an axial rest position in which the end 24F of the intermediate ring 24 is in abutment against the axial stop 18E of the bearing 18 and / or in which the second sealing segment 38 is in abutment against the shoulder 19B of the bearing 18.

[0058] Conversely, when the pressure increases in the chamber 40, in particular when the speed of the turbomachine 1 increases, the resultant of the pressure forces P in the chamber 40 tends to push the intermediate ring 24 opposite the return force of the spring 60. In particular, thanks to the withdrawal 19A of the bearing ring 18D, an oil cavity 46 is enlarged in the chamber 40 between the shoulder 19B and the second sealing segment 38: the pressure of the oil present in this oil cavity 46 then tends to push the second sealing segment 38 and therefore the intermediate ring 24. Therefore, as shown in [Fig. 3], when the resultant of the pressure forces P exceeds the elastic return force E of the spring 60, the intermediate ring 24 moves axially away from its axial rest position, which increases the axial length L of the chamber 40. 40.

[0059] Thus, when the pressure of the damping oil increases in the chamber 40, the intermediate ring 24 automatically moves so as to increase the volume of oil in the chamber 40, which modifies the damping parameters of the bearing 18.

[0060] [Fig. 4] represents a second example of structure around the bearing 118. This second example is entirely similar to the first example except that, in this second example, the internal surface 1211 of the bearing support 120 has a recess 129 while the intermediate ring 124 comprises, at its end 124G, an external collar 153, forming an external projection, extending radially outwards in the space of the recess 129 until it is flush with the internal surface 1211 of the bearing support 120. A second oil cavity 147 is then enlarged in the recess 129 of the bearing support 120, between the shoulder 129A formed by this recess 129 and the outer collar 153 of the intermediate ring 124. This second oil cavity 147 is supplied with oil using a supply channel 120B connected to the supply channel 120A of the chamber 140. A sealing segment 153A is provided at the radial end of the collar 153 in order to ensure the sealing of this second oil cavity 147.

[0061] Thus, in this second example, the resultant of the pressure forces P2 in this second cavity 147 is added to the resultant of the pressure forces PI in the chamber 140 in order to facilitate the axial displacement of the intermediate ring 124 against the elastic return force E of the return device 160.

[0062] Furthermore, in this second example, the bearing ring 120D has a second axial stop 118F configured to cooperate axially with the second axial end 124G of the intermediate ring 124. This second axial stop 118F thus makes it possible to limit the travel of the intermediate ring 124 in the direction opposite to the elastic return force E of the spring 160.

[0063] [Fig. 5] shows a third example of structure around the bearing 218. This third example is completely similar to the second example except that, in this third example, the leaf spring is replaced by a compression spring 260, of the helical spring type. In this example, the spring 260 is installed in a notch 254 of the intermediate ring 224, between a shoulder 254A of this notch 254 and a finger 228 of the bearing support 220 penetrating into this notch 254.

[0064] [Fig. 6] shows a fourth example of structure around the bearing 318. This fourth example is entirely similar to the second example except that, in this fourth example, the axial stop 318E has a conical profile. Similarly, the axial end 324F of the intermediate ring 324 has a conical profile complementary to that of the axial stop 318E. Thus, at low speed, when the intermediate ring 324 is returned against the axial stop 318E by the elastic return device 360, the conical profile of the axial stop 318E limits or completely blocks the freedom of movement of the intermediate ring 324 in the radial direction.

[0065] Furthermore, in this fourth example, the spring 360 is still a leaf spring but it is mounted differently. In this example, the first end of the leaf spring 360 is embedded on the external surface 325E of the intermediate ring 324, close to its axial end 324F, while its second end bears against the lateral surface 327 of the bearing support 320.

[0066] Although the present invention has been described with reference to specific embodiments, it is obvious that modifications and changes may be made to these examples without departing from the general scope of the invention as defined by the claims. In particular, individual features of the different embodiments illustrated / mentioned may be combined in additional embodiments. Therefore, the description and drawings should be considered in an illustrative rather than restrictive sense.

[0067] It is also obvious that all the characteristics described with reference to a method are transposable, alone or in combination, to a device, and conversely, all the characteristics described with reference to a device are transposable, alone or in combination, to a method.

Claims

Claims

1. Turbomachine (10) extending in an axial direction (X) and in a radial direction (R), comprising at least one rotary shaft (16, 17), at least one bearing (18), supporting the rotary shaft (16, 17), a bearing support (20), supporting the bearing (18), a spring element (22), mechanically connecting the bearing support (20) and the bearing (18), an intermediate ring (24), arranged radially between the bearing (18) and the bearing support (20), the intermediate ring (24) being configured to slide axially relative to the bearing (18), a first sealing segment (36), arranged radially between the bearing (18) and the intermediate ring (24) and axially coupled with the bearing (18), a second sealing segment (38), arranged radially between the bearing (18) and the intermediate ring (24) and axially coupled with the intermediate ring (24), wherein the first sealing segment (36), the second sealing segment (38),the bearing (18) and the intermediate ring (24) define a chamber (40) configured to receive oil, the axial length (L) of the chamber (40) being variable depending on the axial position of the intermediate ring (40) relative to the bearing (18), thus forming, when filled with oil, a variable damping film, in which a return device (60) exerts an elastic return force (E) configured to return the intermediate ring (24) to a predetermined axial rest position relative to the bearing (18).,

2. Turbomachine (10) according to claim 1, in which the intermediate ring (24) is configured to be displaced axially relative to the bearing (18), against the elastic return force (E) of the return device (60), under the effect of the pressure of the damping oil present in the chamber (40).

3. Turbomachine (10) according to claim 1 or 2, in which the return device is a leaf spring (60) arranged between the intermediate ring (24) on the one hand and the bearing (18) or the bearing support (20) on the other hand.

4. A turbomachine (210) according to claim 1 or 2, wherein the return device is a compression spring (260), for example a helical spring, placed in compression between the intermediate ring (224) on the one hand and the bearing (218) or the bearing support (220) on the other hand.

5. Turbomachine (10) according to any one of claims 1 to 4, in which an external surface (19E) of the bearing (18) comprises a recess (19A), in which the second sealing segment (38) is positioned, locally widening the chamber (40) so as to form a first cavity (46) whose volume is variable depending on the axial position of the intermediate ring (24) relative to the bearing (18).

6. Turbomachine (10) according to claim 5, in which the intermediate ring (24) comprises an internal projection (52) extending radially inwards so as to be positioned in the recess (19A) of the external surface (19E) of the bearing (18), and in which the second sealing segment (38) is mounted against a shoulder (52A) formed by the internal projection (52) of the intermediate ring (24).

7. A turbomachine (110) according to any one of claims 1 to 6, wherein the bearing support (120) comprises a recess (129), wherein the intermediate ring (124) comprises an external projection (153) extending radially outwards so as to be positioned in the recess (129) of the bearing support (120), wherein the recess (129) of the bearing support (120) and the external projection (153) of the intermediate ring (124) form a second cavity (147), configured to receive damping oil, the volume of which is variable depending on the axial position of the intermediate ring (124) relative to the bearing (118).

8. A turbomachine (110) according to claim 7, wherein the bearing support (120) comprises a first oil circuit (120A) connecting an oil inlet to the chamber (140), and wherein the bearing support (120) comprises a second oil circuit (120B) connecting the oil inlet to the second cavity (147).

9. Turbomachine (310) according to any one of claims 1 to 8, comprising a first axial stop (318E) configured to axially block the intermediate ring (324) relative to the bearing (318) in said predetermined axial rest position of the intermediate ring (324) relative to the bearing (318), wherein the first axial stop (318E) is disposed on an outer surface (319E) of the bearing (318), wherein the first axial stop (318E) has a conical profile, and wherein the intermediate ring (324) comprises a stop surface configured to bear on the first axial stop (318E), said stop surface having a conical profile coinciding with the conical profile of the first axial stop (318E).

10. Turbomachine (110) according to any one of claims 1 to 9, comprising a second axial stop configured to axially block the intermediate ring (124) relative to the bearing (118) in a predetermined axial stop position of the intermediate ring (124) relative to the bearing (118), in the direction opposite to the return force (E) of the return device (160).

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