EP4305738A1

EP4305738A1 - Rotary electric machine for transmission system

Info

Publication number: EP4305738A1
Application number: EP21714300.7A
Authority: EP
Inventors: Jian Wang; Guodong Yu; Jacques Verot
Original assignee: Shanghai Valeo Automotive Electrical Systems Co Ltd; Valeo Equipements Electriques Moteur SAS
Current assignee: Shanghai Valeo Automotive Electrical Systems Co Ltd; Valeo Equipements Electriques Moteur SAS
Priority date: 2021-03-12
Filing date: 2021-03-12
Publication date: 2024-01-17
Also published as: WO2022188139A1; CN116964912A

Abstract

The invention relates to a rotary electric machine (1) able to be fixed to a transmission system, notably to a gearbox, the rotary electric machine (1) having an axis of rotation (A) and comprising: -a stator (2), -a shaft (4) comprising a first end (37), the first end (37) being free and comprising a driving element (13) able to drive a rotary element of the transmission system, -a rotor (3), the rotor being fixed to the shaft (4), -a casing (41) in which the stator (3) is fixed and comprising a first bracket (6) and a second bracket (5), -a first bearing (12), notably a first rolling bearing, mounted in the first bracket (6) and guiding the rotation of the shaft (4), -a second bearing (11), notably a second rolling bearing, mounted in the second bracket (5) and guiding the rotation of the shaft (4), -a first seal (14), distinct from the first bearing (12), the first seal (14) contributing to sealing between the first bracket (6) and the shaft (4), wherein the shaft (4) comprises a sealing land (42) axially between the first bearing (12) and the rotor (3), the first seal (14) being in contact with the sealing land (42).

Description

Rotary electric machine for transmission system

Technical field

The invention relates to a rotary electrical machine for a transmission system.

Background

French patent application FR3086124 A1 discloses a rotary electric machine able to be fixed to a transmission system, notably to a gearbox, the rotary electric machine having an axis of rotation and comprising:
- a stator,
- a shaft comprising a first end, the first end being free and comprising a driving element able to drive a rotary element of the transmission system,
- a rotor, the rotor being fixed to the shaft,
- a casing in which the stator is fixed and comprising a first bracket and a second bracket,
- a first bearing, notably a first rolling bearing, mounted in the first bracket and guiding the rotation of the shaft,
- a second bearing, notably a second rolling bearing, mounted in the second bracket and guiding the rotation of the shaft,
- a first seal, distinct from the first bearing, the first seal contributing to sealing between the first bracket and the shaft,
wherein the shaft comprises a sealing land axially between the first bearing and the shaft driving element, the first seal being in contact with the sealing land.
In such an electric machine, the seal protects the inside of the electric machine from the ingress of liquid such as a transmission system lubricating liquid. The presence of such a seal leads to an increase in the distance between the first bearing and the driving element and therefore leads to a significant length of overhang for the driving element. This length of overhang causes significant bending of the shaft under the effect of radial forces on the driving element. These radial forces are generated for example by the transmission of a torque by gear meshing in instances in which the driving element is a gear, or by the tension in a belt in another instance in which the driving element is a belt drive pulley. The significant bending of the shaft may lead to problems with the operation of the transmission system, notably to the generation of noise and/or to excessive wear. The significant bending of the shaft may also lead to problems with the operation of the rotary electric machine by causing the air gap between the rotor and the stator to vary.
In order to limit this bending it is possible to increase the diameter of the shaft. However, such an increase exhibits a number of disadvantages, such as increasing the cost of the shaft, increasing the size of the rotary electric machine or reducing the amount of space available for the rotor, particularly the amount of space for the rotor magnets, and therefore reducing the performance of the rotary electric machine in the case of a permanent-magnet rotor.
Summary of the invention
The present invention seeks to overcome all or some of these disadvantages.
The invention relates to a rotary electric machine able to be fixed to a transmission system, notably to a gearbox, the rotary electric machine having an axis of rotation and comprising:
- a stator,
- a shaft comprising a first end, the first end being free and comprising a driving element able to drive a rotary element of the transmission system,
- a rotor, the rotor being fixed to the shaft,
- a casing in which the stator is fixed and comprising a first bracket and a second bracket,
- a first bearing, notably a first rolling bearing, mounted in the first bracket and guiding the rotation of the shaft,
- a second bearing, notably a second rolling bearing, mounted in the second bracket and guiding the rotation of the shaft,
- a first seal, distinct from the first bearing, the first seal contributing to sealing between the first bracket and the shaft,
wherein the shaft comprises a sealing land axially between the first bearing and the rotor, the first seal being in contact with the sealing land.
Such positioning of the sealing land makes it possible to reduce the distance between the first bearing and the driving element. Specifically, because the first seal is not between the first bearing and the driving element, there is no need to provide a space for the first seal between the driving element and the first bearing. It is thus possible to bring the driving element closer to the first bearing and thus reduce the length of overhang of the driving element. This therefore makes it possible to reduce the bending of the shaft under the effect of radial forces on the driving element. The operation of the machine is thus improved by reducing the noise and/or the wearing of the machine, and particularly of the driving element. The variations in the air gap between the rotor and the stator are also reduced. It is also possible to use a shaft of smaller diameter, making it possible to reduce the size of the rotary electric machine or increase the amount of space available for the rotor, particularly the amount of space for the rotor magnets, and therefore improve the performance of the rotary electric machine in the case of a permanent-magnet rotor.
According to one additional feature of the invention, the rotary electric machine comprises a first passage able to guide a lubricant of the transmission system into a lubricating space formed between the first bearing and the first seal.
Such a passage guides the transmission system lubricant towards a space between the bearing and the first seal. The presence of the lubricant limits the friction between the first seal and the sealing land. The wearing of the first seal and of the sealing land can be reduced.
According to an additional feature of the invention, the first passage comprises a first hole formed in the first bracket.
The use of a first hole formed in the first bracket for the first passage means that the oil can be guided towards the lubricating space while at the same time limiting modifications at the interface between the first bearing and the first bracket. The use of such a hole also makes it possible to have a first-passage inlet and a first-passage outlet which are at different radial positions with respect to the axis of rotation of the rotary electric machine.
According to an additional feature of the invention, the first bracket comprises a first bearing land in which the first bearing is mounted.
According to an additional feature of the invention, the first passage comprises a first groove formed in the first bearing land.
The use of such a groove limits the radial size, with respect to the axis of rotation, of the first passage. Specifically, because part of a wall that forms the first passage is formed by an exterior surface of the first bearing, there is therefore no material belonging to the first bracket between the first bearing and the first passage.
According to one additional feature of the invention, the rotary electric machine comprises a second passage able to allow the transmission-system lubricant to exit the lubricating space.
The use of such a second passage improves the flow of lubricant in the lubricating space. Because the lubricant is able to exit the lubricating space towards the transmission system, the risk of a build-up of impurities in the lubricating space is reduced. This reduction in the build-up of impurities limits the wearing of the first seal and of the sealing land and therefore improves the reliability of the rotary electric machine. The lubricant may for example be filtered if necessary using a filtration system belonging to the transmission system.
According to an additional feature of the invention, the second passage comprises a second hole formed in the first bracket.
The use of a second hole formed in the first bracket for the second passage means that the oil can be guided away from the lubricating space while at the same time limiting modifications at the interface between the first bearing and the first bracket. The use of such a hole also makes it possible to have a second-passage inlet and a second-passage outlet which are at different radial positions with respect to the axis of rotation of the rotary electric machine.
According to an additional feature of the invention, the second passage comprises a second groove formed in the first bearing land.
The use of such a second groove limits the radial size, with respect to the axis of rotation, of the second passage. Specifically, because part of a wall that forms the second passage is formed by an exterior surface of the first bearing, there is therefore no material belonging to the first bracket between the first bearing and the second passage.
According to an additional feature of the invention, the first passage comprises a first outlet opening into the lubricating space and the second passage comprises a first inlet opening into the lubricating space, the first inlet being located vertically below the first outlet so as to be able to contribute towards the transmission-system lubricant exiting the lubricating space under the effect of gravity.
Such a relative position of the first outlet of the first passage in relation to the first inlet of the second passage improves the flow of lubricant in the lubricating space.
According to an additional feature of the invention, the first seal is borne by the first bracket.
A first seal borne by the first bracket reduces the cost of the rotary electric machine. This is because the absence of an intermediate component between the seal and the first bracket reduces the number of components of the rotary electric machine.
According to an additional feature of the invention, the rotary electric machine comprises a retaining ring, the retaining ring comprising a second land, the first seal being fixed, notably by force-fitting, to the second land.
According to an additional feature of the invention, the retaining ring comprises a cylindrical part and a discoid part, the second land being situated radially on the inside of the cylindrical part, the discoid part being fixed to the first bracket notably using a screw.
The use of a discoid part in addition to a cylindrical part bearing the first seal means that the retaining ring can be secured in a smaller amount of space.
According to an additional feature of the invention, a second seal, notably an O-ring seal, is interposed between the retaining ring and the first bracket.
The use of such a second seal contributes to sealing between the lubricating space and the inside of the rotary electric machine. The losses of transmission system lubricant into the rotary electric machine, and therefore out of the transmission system, are thus limited.
According to an additional feature of the invention, the retaining ring bears axially against the first bearing.
This feature contributes to axial attachment of the first bearing in the first bracket.
According to an additional feature of the invention, the first bearing is a first rolling bearing comprising an outer ring, the retaining ring bearing against the outer ring.
According to an additional feature of the invention, the first passage and/or the second passage respectively comprise a first opening, notably a first slot, and a second opening, notably a second slot, which are formed in the retaining ring.
The first opening and the second opening which are formed in the retaining ring allow the lubricant to flow through the retaining ring.
According to an additional feature of the invention, the first seal is a lip seal.
The invention also relates to a rotary electric machine able to be fixed to a transmission system, notably to a gearbox, the rotary electric machine having an axis of rotation and comprising:
- a stator,
- a shaft comprising a first end, the first end being free and comprising a driving element able to drive a rotary element of the transmission system,
- a rotor, the rotor being fixed to the shaft,
- a casing in which the stator is fixed and comprising a first bracket and a second bracket,
- a first bearing, notably a first rolling bearing, mounted in the first bracket and guiding the rotation of the shaft,
- a second bearing, notably a second rolling bearing, mounted in the second bracket and guiding the rotation of the shaft,
- a first seal, distinct from the first bearing, the first seal contributing to sealing between the first bracket and the shaft,
wherein the first bearing is situated axially between a sealing land and the driving element, the first seal being in contact with the sealing land.
Such positioning of the first bearing makes it possible to reduce the distance between the first bearing and the driving element. Specifically, because the first seal is not between the first bearing and the driving element, there is no need to provide a space for the first seal between the driving element and the first bearing. It is thus possible to bring the driving element closer to the first bearing and thus reduce the length of overhang of the driving element. This therefore makes it possible to reduce the bending of the shaft under the effect of radial forces on the driving element. The operation of the machine is thus improved by reducing the noise and/or the wearing of the machine, and particularly of the driving element. The variations in the air gap between the rotor and the stator are also reduced. It is also possible to use a shaft of smaller diameter, making it possible to reduce the size of the rotary electric machine or increase the amount of space available for the rotor, particularly the amount of space for the rotor magnets, and therefore improve the performance of the rotary electric machine in the case of a permanent-magnet rotor.
Throughout the foregoing, the rotor may comprise any number of pairs of poles, for example six or eight pairs of poles.
Throughout the foregoing, the rotary electric machine may have a stator having a polyphase electric winding, for example formed of wires or of conducting bars connected to one another.
The rotary electric machine may comprise a power electronics component able to be connected to the on-board network of a vehicle. This power electronics component for example comprises an inverter/rectifier allowing a vehicle on-board network to be charged, or which can be electrically powered by this network, according to whether the rotary electric machine is operating as a motor or as a generator.

Brief description of the drawings

The invention may be better understood on reading the following description of nonlimiting exemplary embodiments thereof and on studying the appended drawing, in which:
- Figure 1 depicts a schematic part view in section of a rotary electric machine,
- Figure 2 depicts a schematic part view in section of a rotary electric machine according to a first embodiment of the invention,
- Figure 3 depicts another schematic part view in section of the rotary electric machine of Figure 2,
- Figure 4 depicts a schematic part view of the rotary electric machine of Figure 2,
- Figure 5 depicts another schematic part view of the rotary electric machine of Figure 2.
Detailed description of the embodiments
In all figures, elements that are identical or perform the same function bear the same reference numerals. The following embodiments are examples. Although the description refers to one or more embodiments, this does not necessarily mean that each reference relates to the same embodiment, or that the features only apply to just one embodiment. Individual features of different embodiments can also be combined or interchanged in order to create other embodiments.
Figure 1 depicts a schematic part view in section of a rotary electric machine 1 having an axis of rotation A. The rotary electric machine 1 comprises a stator 2 and a rotor 3 inside a casing 41. The rotor 3 is able to interact with the stator 2. The casing 41 comprises for example a first bracket 6, a second bracket 5 and a tubular spacer 7. The tubular spacer 7 is for example clamped between the first bracket 6 and the second bracket 5, for example using through-bolts, not depicted, between the first bracket 6 and the second bracket 5. The stator 2 is fixed inside the casing 41, for example tightly fitted into the tubular spacer 7.
Within the meaning of the invention, unless specified otherwise, the terms radial and radially are to be understood with respect to the axis of rotation A. Within the meaning of the invention, unless specified otherwise, the terms longitudinal and longitudinally mean in the direction of the axis of rotation A. In a non-depicted embodiment of the invention, the tubular spacer comprises a cooling chamber in which a liquid coolant circulates.
In a non-depicted embodiment of the invention, there is no tubular spacer and the stator is clamped between the first bracket and the second bracket.
The stator comprises a stator body 9 and a winding 8. The stator body 9 comprises for example a first stack of magnetic laminations. For example, the winding 8 comprises electrical conductors of which an active part passes through slots formed in the stator body 9 and a connecting part or winding overhang is formed outside of the slots. The winding 8 is for example a winding of the hairpin-winding type.
The rotor 3 is fixed on a shaft 4 with axis of rotation A. The shaft 4 is guided in rotation by a first bearing 12 mounted in the first bracket 6 and a second bearing 11 mounted in the second bracket 5. The shaft 4 comprises a first end 37. The first end 37 is free and comprises a driving element 13. The shaft 4 may comprise several elements as in the embodiment depicted in the figures. The shaft for example comprises an elongate element 52 oriented along the axis of rotation A, and a pinion 53 used as a driving element 13.
The first end is free in so far as it is not guided by an additional bearing with respect to the casing 41 of the rotary electric machine 1 or with respect to a casing of the transmission system fixed to the casing 41 of the rotary electric machine 1.
As depicted in Figure 2, the driving element 13 is, for example, fixed to the elongate element 52 using a screw (not depicted) screwed into a threaded hole 28. In the embodiment depicted in the figures, the first bearing 12 is a rolling bearing of which the inner ring bears against a first shoulder 31 of the elongate element 52 of the shaft 4. This bearing pressure is afforded for example by the tightening of the screw, the driving element 13 bearing against the inner ring of the rolling bearing for example via a ring 30 as the screw is tightened.
As depicted in Figure 5, a rotational connection between the elongate element 52 and the driving element 13 is afforded for example by a system of splines 29.
In another, non-depicted, embodiment of the invention, a rotational connection between the elongate element 52 and the driving element 13 is afforded for example using a key.
In another, non-depicted, embodiment of the invention, the driving element is a pulley able to drive a belt.
In another, non-depicted, embodiment of the invention, the driving element is a sprocket wheel able to drive a chain.
In another, non-depicted, embodiment of the invention, the shaft comprises an elongate element oriented along the axis of rotation A, and in which the driving element 13 is formed as an integral part. For example, meshing teeth are machined at the first end 37 of the shaft 4.
The first bearing 12 is, for example, a first rolling bearing, particularly a ball bearing. The second bearing 11 is, for example, a second rolling bearing, particularly a ball bearing.
In another, non-depicted, embodiment of the invention, the first bearing is a plain bearing.
In another, non-depicted, embodiment of the invention, the second bearing is a plain bearing.
The rotary electric machine 1 further comprises a first seal 14. The first seal 14 contributes to sealing between the first bracket 6 and the shaft 4. The shaft 4 comprises a sealing land 42. The first seal 14 is in contact with the sealing land 42. For example, the seal may slide over the sealing land 42 as the shaft 4 rotates. The sealing land 42 is axially between the first bearing 12 and the rotor 3.
The first seal 14 is, for example, a lip seal.
For example, the shaft 4 comprises a rotor land 38 to which the rotor is attached and a third bearing land 39 in contact with the first bearing 12. The sealing land 42 is axially between the third bearing land 39 and the rotor land 38.
For example, the shaft 4 comprises a fourth bearing land 40 in contact with the second bearing 11.
The rotary electric machine 1 is for example fixed to the transmission system 50. The transmission system 50, for example a mechanical reducer, a variable-speed drive or a gearbox comprises a housing. One wall 51 of the first bracket 6 forms, for example, part of an internal envelope of the housing of the transmission system 50. The wall 51 may therefore for example be in contact with a lubricant of the transmission system 50. For example, lubricant of the transmission system 50 may be thrown against the wall 51 as internal components of the transmission system, notably gears, rotate.
The rotary electric machine 1 may comprise a first passage 18 able to guide a lubricant of the transmission system into a lubricating space 43 formed between the first bearing 12 and the first seal 14.
The first passage 18 may comprise a first hole 44 formed in the first bracket 6.
The first bracket 6 may comprise a first bearing land 45 in which the first bearing 12, for example the first rolling bearing, is mounted.
In another, non-depicted, embodiment of the invention, the first passage 18 comprises a first groove formed in the first bearing land 45.
In another, non-depicted, embodiment of the invention, the first passage 18 comprises a first hole formed in the first bracket 6, and a first groove formed in the first bearing land 45, the first hole opening into the first groove. In this embodiment of the invention, the first groove is, for example, closed at that one of its axial ends that is situated axially closest to the first end 37 of the shaft 4.
The rotary electric machine 1 may comprise a second passage 19 able to allow the transmission-system lubricant to exit the lubricating space 43.
The second passage 19 may comprise a second hole 46 formed in the first bracket 6.
In another, non-depicted, embodiment of the invention, the second passage 19 comprises a second groove formed in the first bearing land 45.
In another, non-depicted, embodiment of the invention, the second passage comprises a second hole formed in the first bracket 6, and a second groove formed in the first bearing land 45, the second hole opening into the second groove. In this embodiment of the invention, the second groove is, for example, closed at that one of its axial ends that is situated axially closest to the first end 37 of the shaft 4.
The first passage 18 may comprise a first outlet 20 opening into the lubricating space 43 and the second passage 19 comprises a first inlet 21 opening into the lubricating space 43. The first inlet 21 is, for example, located vertically below the first outlet 20 so as to be able to contribute towards the transmission-system lubricant exiting the lubricating space 43 under the effect of gravity.
The first passage 18 may further comprise a second inlet 25 via which the lubricant enters the first passage 18. The second inlet 25 is formed for example in the wall 51 of the first bracket 6. The second inlet 25 is, for example, located vertically above the first outlet so as to encourage the lubricant to flow from the second inlet 25 towards the first outlet 20.
As depicted in Figure 5, the wall 51 may comprise a rib 35. The second inlet 25 is, for example, situated in the vicinity of the rib 35 so that the rib 35 guides the lubricant, notably lubricant trickling along the wall 51, towards the second inlet 25. The distance between the rib 35 and the second inlet 25 is, for example, shorter than the longest dimension of the second inlet 25 measured in a plane perpendicular to the axis of rotation A.
The second passage 19 may further comprise a second outlet 26 via which the lubricant exits the second passage 19. The second outlet 26 is formed for example in the wall 51 of the first bracket 6. The second outlet is, for example, located vertically below the first inlet so as to encourage the lubricant to flow from the first inlet towards the second outlet.
The rotary electric machine 1 may comprise a plurality of first passages 18 and/or of second passages 19.
The rotary electric machine 1 may comprise a plurality of ribs 35.
The rotary electric machine 1 according to the embodiment depicted in the figures comprises two first passages 18, the second inlet 25 of each of them being situated in the vicinity of a rib 35.
As depicted in Figure 3, the rotary electric machine 1 comprises, for example, a retaining ring 16. The retaining ring 16 may comprise a second land 47. The first seal 14 is, for example, fixed, notably by force-fitting, to the second land 47.
The retaining ring 16 comprises, for example, a cylindrical part 48 and a discoid part 49. The second land 47 is, for example, situated radially on the inside of the cylindrical part 48.
As depicted in Figure 3 and Figure 4, the discoid part 49 is, for example, attached to the first bracket 6 notably using a screw 32. The screw 32 is, for example, screwed into the threaded hole 33 formed in the first bracket 6. In the example depicted in the figures, the discoid part 49 is attached to the first bracket by three screws 32.
The rotary electric machine 1 may further comprise a second seal 27 interposed between the retaining ring 16 and the first bracket 6. The second seal 27 is, for example, an O-ring seal. In the embodiment of the invention depicted in the figures, the second seal 27 is situated in a space delimited at least in part by a face of the discoid part 49 that faces the first bracket 6, a face of the cylindrical part 48 that faces the first bracket 6, and a chamfer formed in the first bracket 6.
In another, non-depicted, embodiment of the invention, the second seal 27 is an O-ring seal housed in a groove formed on a face of the first bracket that faces the cylindrical part 48.
The retaining ring 16, notably the cylindrical part 48, may bear axially against the first bearing 12.
In the embodiment depicted in the figures, the first bearing 12 is a first rolling bearing comprising an outer ring. The retaining ring 16, notably the cylindrical part 48, bears for example against the outer ring so as to axially block the outer ring between a second shoulder 54 formed on the first bracket 6 and the retaining ring 16.
The first passage 18 may comprise a first opening 22, notably a first slot, formed in the retaining ring 16.
The second passage 19 may comprise a second opening 23, notably a second slot, formed in the retaining ring 16.
In another, non-depicted, embodiment of the invention, the first seal 14 is borne by the first bracket 6.

Claims

Rotary electric machine (1) able to be fixed to a transmission system, notably to a gearbox, the rotary electric machine (1) having an axis of rotation (A) and comprising:

a. a stator (2) ,

b. a shaft (4) comprising a first end (37) , the first end (37) being free and comprising a driving element (13) able to drive a rotary element of the transmission system,

c. a rotor (3) , the rotor being fixed to the shaft (4) ,

d. a casing (41) in which the stator (3) is fixed and comprising a first bracket (6) and a second bracket (5) ,

e. a first bearing (12) , notably a first rolling bearing, mounted in the first bracket (6) and guiding the rotation of the shaft (4) ,

f. a second bearing (11) , notably a second rolling bearing, mounted in the second bracket (5) and guiding the rotation of the shaft (4) ,

g. a first seal (14) , distinct from the first bearing (12) , the first seal (14) contributing to sealing between the first bracket (6) and the shaft (4) ,

wherein the shaft (4) comprises a sealing land (42) axially between the first bearing (12) and the rotor (3) , the first seal (14) being in contact with the sealing land (42) .
Rotary electric machine (1) according to the preceding claim, comprising a first passage (18) able to guide a lubricant of the transmission system into a lubricating space (43) formed between the first bearing (12) and the first seal (14) .
Rotary electric machine (1) according to the preceding claim, wherein the first passage (18) comprises a first hole (44) formed in the first bracket (6) .
Rotary electric machine (1) according to either of Claims 1 and 2, wherein the first bracket (6) comprises a first bearing land (45) in which the first bearing (12) is mounted.
Rotary electric machine (1) according to the preceding claim, wherein the first passage (18) comprises a first groove formed in the first bearing land (45) .
Rotary electric machine (1) according to one of Claims 2 to 5, comprising a second passage (19) able to allow the transmission-system lubricant to exit the lubricating space (43) .
Rotary electric machine (1) according to the preceding claim, wherein the second passage (19) comprises a second hole (46) formed in the first bracket (6) .
Rotary electric machine (1) according to Claim 6 considered in combination with Claim 4, wherein the second passage (19) comprises a second groove formed in the first bearing land (45) .
Rotary electric machine (1) according to one of Claims 6 to 8, wherein the first passage (18) comprises a first outlet (20) opening into the lubricating space (43) and the second passage (19) comprises a first inlet (21) opening into the lubricating space (43) , the first inlet (21) being located vertically below the first outlet (20) so as to be able to contribute towards the transmission-system lubricant exiting the lubricating space (43) under the effect of gravity.
Rotary electric machine (1) according to one of Claims 1 to 9, comprising a retaining ring (16) , the retaining ring (16) comprising a second land (47) , the first seal (14) being fixed, notably by force-fitting, to the second land (47) .
Rotary electric machine (1) according to the preceding claim, wherein the retaining ring (16) comprises a cylindrical part (48) and a discoid part (49) , the second land (47) being situated radially on the inside of the cylindrical part (48) , the discoid part (49) being fixed to the first bracket (6) notably using a screw (32) .
Rotary electric machine (1) according to the preceding claim, wherein a second seal (27) , notably an O-ring seal, is interposed between the retaining ring (16) and the first bracket (6) .
Rotary electric machine (1) according to one of Claims 10 to 12, wherein the retaining ring (16) bears axially against the first bearing (12) .
Rotary electric machine (1) according to the preceding claim, wherein the first bearing (12) is a first rolling bearing comprising an outer ring, the retaining ring (16) bearing against the outer ring.
Rotary electric machine (1) according to one of Claims 10 to 14 considered in combination with Claim 6, wherein the first passage (18) and/or the second passage (19) respectively comprise a first opening (22) , notably a first slot, and a second opening (23) , notably a second slot, which are formed in the retaining ring (16) .