SUPPORT DEVICE FOR A STATOR IN A HOUSING

Abstract

A SUPPORT DEVICE FOR A STATOR IN A HOUSING This subject relates to a rotating electrical machine (100) comprising a rotor, a stator (104), a housing (110), and a support device (112). The rotor can rotate about an axis of rotation (116). The stator (104) is arranged coaxially with the rotor. The stator (104) comprises a stator core (106) and a winding (108a; 108b). The housing (110) comprises a chamber defined by a closed end (120) at one end and an open end (118) at the other. The chamber receives at least most of the rotor and stator (104). The inner surface of the housing and the outer surface of the stator core form an annular space (114) extending axially between the two. The support device (112) is at least partially disposed between the stator core (106) and the housing (110). The support device (112) covers at least partially the annular space (114).The support device (112) is adapted to at least limit the radial displacement of the stator core (106) relative to the rotational axis (116). Figure for the abbreviation: Fig. 1 [Fig. 1].

Description

Title of the invention: SUPPORT DEVICE FOR A STATOR IN A HOUSING FIELD OF INVENTION

[0001] The present subject relates to a support device for a stator in a housing of a rotating electrical machine.

[0002] CONTEXT

[0003] Rotating electric machines are widely used in automotive applications, particularly as traction motors. Rotating electric machines generally comprise a stator and a rotor arranged coaxially, with the rotor configured to rotate about an axis of rotation. The stator and rotor are positioned facing each other along the axis of rotation within a housing. The rotor is mounted on a rotor shaft that extends from the housing to mechanically interact with a pulley or gear to facilitate torque transfer. In a known configuration, the stator is supported by a bracket located within the housing. In this case, the rotor is positioned inside a cavity in the stator. Furthermore, a gap is maintained between the outer periphery of the stator and the inner periphery of the bracket.Such a space is particularly necessary in liquid-cooled rotating electrical machines, where a cooling fluid circulates through this space. This space acts as a channel allowing the distribution of a cooling fluid, such as oil, to cool the stator.

[0004] In a conventional rotating electrical machine with the configuration described above, it is important to maintain a uniform gap along the entire length of the stator. In other words, the gap width, or the distance between the outer periphery of the stator and the inner periphery of the support, should preferably remain uniform throughout the lifetime of the rotating electrical machine. The stator is supported at one end and cantilevered at the other. A cantilever effect is induced at the unsupported end of the stator, causing deformation due to the stator's weight. Such a deflection can also occur when exposed to vibrations. This negatively affects the gap maintained between the stator and the support. This deflection occurs particularly in the radial direction with respect to the rotor's axis of rotation, thereby compromising the structural integrity of the channels.Specifically, the circulation of the cooling fluid through the channels is obstructed. As a result, the stator windings are not cooled as intended. In particular, adequate circulation of the cooling fluid is not achieved, which reduces the machine's performance. Rotating electric motors. Generally speaking, due to the stator cantilever effect and the deflection caused by the stator's weight, the structural and operational integrity of the rotating electric motor are compromised. Furthermore, stator deflection can lead to inefficient magnetic field interference between the stator and the rotor. A rotating electric motor with this configuration therefore tends to operate poorly and inefficiently.

[0005] Therefore, the technical problem to be solved by the present object is to ensure that the space between the housing and the stator is uniform and maintained independently of factors such as exposure to vibrations and the weight of the stator. Summary of the invention

[0006] The present object aims to solve the aforementioned technical problem in conventional rotating electrical machines. This object finds particularly advantageous application in rotating electrical machines such as alternators, alternator starters, reversible machines, or electric motors. A reversible machine is a rotating electrical machine that can operate reversibly, on the one hand as an electric generator in the function of an alternator, and on the other hand as an electric motor, for example, to start the internal combustion engine of a motor vehicle. The rotating electrical machine described here can also be used as a traction motor for hybrid or electric vehicles.

[0007] The present subject relates to a rotating electrical machine comprising: a rotor rotating about an axis of rotation; a stator, arranged coaxially with the rotor, comprising a stator core and a winding; a housing comprising a chamber defined by a closed end at one end and an open end at the other, the chamber receiving at least largely the rotor and the stator, in which an inner surface of the housing and an outer surface of the stator core form an annular space extending axially between the two; a support device at least partially disposed between the stator core and the housing, said support device covering at least partially the annular space and adapted to at least limit the radial displacement of the stator core with respect to the axis of rotation. Consequently, the radial displacement or deflection of the stator is limited. The integrity of the annular space is maintained.In other words, the annular space defines a radial width between the outer surface of the stator core and the inner diameter of the housing, and this radial width is kept uniform over the entire length of the stator.

[0008] According to one aspect of the present subject, the support device comprises a lower surface facing the closed end of the housing and resting on a first recess formed on the inner surface of the housing, the first recess being A radially outward undercut from the axis of rotation limits the axial movement of the support device, particularly towards the closed end. The support device is thus assembled. It can be assembled with a tight fit between the inner surface of the housing and the outer surface of the stator core. The support device can also be secured using fasteners.

[0009] According to an example in this subject, the support device comprises at least one channel that is at least partially formed and extends in an axial direction parallel to the axis of rotation. This at least one channel is aligned with the annular space so as to ensure adequate and uninterrupted flow of the cooling fluid within the annular space. The support device thus has the additional function of maintaining the flow of the cooling fluid while eliminating radial displacement of the stator.

[0010] According to an example in this subject, the support device defines at least one flange that extends axially from the lower surface of the support device. This at least one flange mechanically reinforces the structural integrity of the support device. The aforementioned advantage is particularly applicable when the width of the support device is small, the width being defined as the distance between the upper and lower surfaces of the support device.

[0011] According to one aspect of the present subject, each of the at least one flange is disposed in a second recess formed on the inner surface of the housing, the second recess being an undercut formed radially outwards from the axis of rotation. Consequently, the at least one flange can facilitate indexing during the assembly of the support device to the housing of the rotating electrical machine.

[0012] According to one aspect of the present object, the first recess is formed further along in the radial direction, from the axis of rotation, than the second recess. Consequently, once assembled, the lower surface rests on the first recess while at least one flange is located inside the second recess.

[0013] According to an example in this subject, at least one channel is at least partially formed on an inner face of the support device. An outer side of the support device is in contact with the inner surface of the housing, and the inner side is in contact with the outer surface of the stator core in order to prevent radial movement of the stator.

[0014] According to another example of the present subject, at least one flange is formed near the inner face and each of at least one channel is formed along one of the at least one flange, in which at least one channel extends in the axial direction. This orientation of at least one channel aligns it with the annular space, thus facilitating the flow of the cooling fluid through the support device.

[0015] According to another example, the stator core comprises corresponding partial channels that correspond to the at least one channel formed on the support device, said at least one channel and the corresponding partial channels forming a conduit configured for the circulation of the cooling fluid. In other words, the cooling fluid circulation conduit is partially formed on the support device and partially formed on the stator core. Thus, when the support device is assembled to the rotating electrical machine, the at least one channel and the corresponding partial channels are aligned together to form the conduit through which the cooling fluid can flow.

[0016] According to yet another example, at least one channel forms a conduit in the support device, and the conduit is oriented in the axial direction. In other words, the conduit is fully formed within the support device to allow the cooling fluid to flow.

[0017] In an example of the present subject, the support device is formed of an electrically insulating material. Brief description of the drawings

[0018] The features, aspects, and advantages of the present invention will be better understood in the light of the following description and the accompanying figures. The description refers to the accompanying drawings, in which:

[0019] [Fig. 1] illustrates a cross-sectional view of a rotating electrical machine, configured in accordance with the present subject; and

[0020] [Fig.2] illustrates a zoomed perspective view of the rotating electrical machine represented in [Fig. 1], configured according to the present subject;

[0021] [Fig.3] illustrates an exploded view of the rotating electrical machine, configured in accordance with the present subject;

[0022] [Fig.4A] illustrates a support device for the rotating electrical machine, in accordance with the present subject;

[0023] [Fig.4B] illustrates another perspective view of the support device, in accordance with the present subject; and

[0024] [Fig. 5] illustrates a zoomed perspective of the support device arranged between a stator and a housing of the rotating electrical machine, configured in accordance with this subject.

[0025] The figures are not necessarily to scale and the size of certain parts may be exaggerated to illustrate the example shown more clearly. In addition, the drawings provide examples and / or examples that conform to the description, but the description is not limited to the examples and / or examples provided in the drawings. DETAILED DESCRIPTION

[0026] In the following description, reference is made to the accompanying drawings, which form an integral part of the invention and illustrate specific embodiments in which the invention can be implemented. These embodiments are described in sufficient detail to enable a person skilled in the art to practice the invention, and it is understood that the embodiments can be combined, or that other embodiments can be used, and that structural and logical modifications can be made without departing from the scope of the present invention. The detailed description that follows should therefore not be taken in a limiting sense, and the scope of the present invention is defined by the appended claims and their equivalents.

[0027] Figure 1 illustrates a cross-sectional view of a rotating electrical machine 100, configured according to the present subject. The present subject relates to a rotating electrical machine 100 comprising a rotor (not shown), a stator 104, a housing 110, and a support device 112. The rotor can rotate about a rotational axis 116. The stator 104 is arranged coaxially with the rotor. The stator 104 comprises a core 106 and windings 108a, 108b. The housing 110 comprises a chamber 122 defined by a closed end 120 at one end and an open end 118 at the other end. The chamber 122 receives at least a large part of the rotor and the stator 104. The inner diameter of the housing and the outer surface of the stator form an annular space 114 extending axially between the two. The support device 112 is at least partly disposed between the stator core 106 and the housing 110.In addition, the support device 112 covers at least part of the annular space 114 and is adapted to at least limit the radial displacement of the stator core 106. Radial displacement refers to a displacement of the stator core 106 relative to the axis of rotation 116.

[0028] For the purposes of this object:

[0029] The terms "axially" or "axial direction" refer to "a direction parallel to the axis of rotation 116 of the rotor",

[0030] "radial" or "radially" means "in a plane perpendicular to the axis of rotation 116 of the rotor and along a straight line intersecting this axis of rotation 116",

[0031] The term "annular space" in annular space 114 refers to "a space which at least partially bypasses the outer surface of the stator core or at least partially the inner surface of the housing".

[0032] The stator core 106 extends lengthwise along the axial direction. One end of the stator core 106, along the axial direction, is mounted (and therefore supported) on the housing 110 by fasteners, and the other end is supported by the support device 112. Thus, the stator core 104 is supported at both ends. The annular space 114 is therefore uniformly supported in the axial direction.

[0033] According to an example in this subject, the stator core 106 is a laminated stator core 106 comprising a plurality of stacked laminations (not shown), although it is possible that the stator core 106 may not be laminated. The stator core 106, in this example, comprises a ferromagnetic material such as steel, although the use of one or more electrically conductive materials is permitted without departing from the scope of this subject. Preferably, the stator core 106 comprises a plurality of arc-spaced teeth generally extending radially. More particularly, each tooth comprises a stirrup generally extending around the circumference, a generally radial arm extending from the stirrup, and a crown generally extending around the circumference of the arm.The winding 108a, 108b is an electrically conductive wire wound several times around each tooth to form a plurality of turns or loops. The electrically conductive wire is preferably made of copper or aluminum, although one or more electrically conductive materials or a combination thereof may be used within the scope of this subject. Furthermore, the wire may or may not be coated. The wiring is wound around the teeth in a particular manner depending on the configuration and desired performance characteristics of the rotary electrical machine 100. The windings 108, 108b may also be made of insulated copper bars (or aluminum, or a combination of both) in the form of what are called pins, U-pins, or hairpins.

[0034] In an example where the rotary electric machine 100 is used to propel a motor vehicle, the rotary electric machine 100 can operate in motor mode in which an electric current passes through the winding 108a, 108b, creating a magnetic field that causes the rotor to rotate. When the rotary electric machine 100 operates in generator mode, the rotation of the rotor creates a magnetic field in the stator 104, this magnetic field being converted into an electric current that flows through the winding 108a, 108b of the stator 104 to supply power to various equipment in the motor vehicle.

[0035] According to one aspect of the present subject, the stator core 106 is disposed in the chamber 122 through the open end 118 of the housing 110. The stator core 106 is rigidly mounted inside the housing 110. The rotor is disposed in a central cavity of the stator core 106. The rotor is capable of rotating relative to the stator 104, and more specifically of rotating about the axis of rotation 116. The rotor is supported by a shaft (not shown) and can rotate about the axis of rotation 116 in motor mode and / or in generator mode of the rotating electric machine 100. Furthermore, the support device 112 is arranged axially towards the open end 118 of the housing 110, in a direction along the axis of rotation 116, such that it is at least partially arranged axially between the stator core 104 and the housing 110. The support device 112 is arranged so as to cover at least partially the annular space 114. In other words, the support device 112 extends at least partially axially into the annular space 114. Consequently, during the operation of the rotating electric machine 100, the stator 104 does not move radially.Furthermore, the rotation axis 116 does not deviate from its intended initial position, which ensures that the stator 104 does not move radially and does not negatively affect the rotation of the rotor. Structural and operational integrity is therefore maintained.

[0036] Figure 2 illustrates an enlarged view of the rotating electric machine 100 also shown in Figure 1. According to the present subject, the support device 112 is arranged so that it is at least partially located between the stator core 106 and the housing 110. More specifically, the support device 112 is arranged so that at least a portion extends axially into the annular space 114. The annular space 114 extends substantially along the length of the stator core 106. Thanks to the support device 112, the annular space 114 is maintained uniformly along the length of the stator core 106.

[0037] According to one aspect of the present subject, the support device 112 comprises a lower surface. The lower surface faces the closed end 120 of the housing 110. When the support device 112 is disposed between the stator core 106 and the housing 110, the lower surface rests on a first indentation 204 formed on the inner surface of the housing. The first indentation 204 is an undercut formed on the inner surface of the housing. The aforementioned undercut is formed radially outward from the axis of rotation 116. In the example illustrated in the figures, the first indentation 204 is formed continuously on the inner surface of the housing.

[0038] According to an example in this subject, the support device 112 comprises at least one channel 202, each being at least partially formed. The at least one channel 202 extends axially, more precisely towards the closed end 120 of the housing 110. The at least one channel 202 is formed as a conduit for the uninterrupted flow of the cooling fluid into the annular space 114. Consequently, the cooling fluid can enter or exit the annular space 114. The aforementioned configuration is particularly advantageous for rotating electrical machines. 100 liquid-cooled. In such rotating electrical machines 100, the annular space 114 allows the flow of the cooling fluid and directs said cooling fluid towards the windings 108a, 108b of the stator 104. In a non-limiting example, the cooling fluid is allowed to enter radially into the housing 110 through an orifice (not shown) formed on the housing 110 and to flow into the annular space 114. The cooling fluid, for example, cooling oil, water, etc., is then dispersed to cool the windings 108a, 108b of the stator 104. The annular space 114 has a radial width between the outer surface of the stator core and the inner diameter of the housing. The aforementioned radial width of the annular space 114 is uniform over the entire length of the stator 104 thanks to the support device 112.A constant flow of the cooling fluid is thus maintained during the operation of the rotating electrical machine 100. Thus, the support device 112 has a dual function - firstly, to maintain the radial width of the annular space 114 over the length of the stator core 106; and secondly, to maintain an uninterrupted flow of cooling fluid in the annular space 114 during the operation of the rotating electrical machine 100.

[0039] Figure 3 illustrates an exploded view of the rotary electric machine 100, as shown in an example from this topic. Figure 4A illustrates support device 112 as shown in an example from this topic. Figure 4B illustrates another perspective view of support device 112 shown in Figure 4A. For brevity, the following description refers to Figures 3, 4A, and 4B together.

[0040] The support device 112, as explained in the preceding description, is disposed at least partially between the stator core 106 and the housing 110. The support device 112 contours around the outer surface 304 of the stator core 104 and is disposed at least partially within the annular space 114 formed between the inner surface 300 of the housing and the outer surface 304 of the stator core. In the example of [Fig. 3], the stator core 106 has a substantially star-shaped profile. Consequently, in this example, the inner surface of the housing 300 is formed with a complementary star-shaped profile to accommodate the stator core 106. Furthermore, when the stator 104 is placed in a chamber 122 of the housing 110, the annular space 114 is formed with a star-shaped profile.Therefore, in the illustrated example, the support device 112 is also formed in a substantially star-shaped profile so as to bypass the stator core 106 and to be disposed at least partly in the annular space 114. The above example is a non-limiting configuration of the rotating electric machine 100. The stator core 106, in particular the outer surface of the stator core 304, and consequently the inner surface of the housing 300, may alternatively have a profile at least substantially circular. Moreover, in the previous example, the annular space 114 is formed with at least one substantially circular profile. Consequently, the support device 112 has a substantially circular profile.

[0041] Figure 4A shows an upper surface 400, an inner side 404, and an outer side 406 of the support device 112, while Figure 4B illustrates a lower surface 402. The lower surface 402 rests on a first recess 204 formed on the inner surface of the housing 300 (illustrated in Figure 2). The support device 112 is oriented so that the lower surface 402 faces the closed end 120 of the housing 110. When the support device 112 is placed in the annular space 114, the inner side 404 is in contact with the outer surface 304 of the stator core, and the outer side 406 is in contact with the inner surface 300 of the housing. The outer side 404 is specifically configured to rest on the first recess 204.In one example, the support device 112 is arranged in the annular space 114 in a tight fit between the outer surface of the stator core 304 and the inner surface of the housing 300. In yet another example (not shown), the support device 112 is fixed to the housing 110, in particular to the first recess 204, by means of fasteners, such as screws, rivets, etc., inserted into holes formed axially on the support device 112. Thus, the support device 112 does not loosen during its use in the rotating electrical machine 100.

[0042] According to the examples shown, in particular in [Fig.4A] and 4B, there are four channels 202, each adapted to allow the circulation of the cooling fluid in the annular space 114. The four channels 202 are aligned axially towards the closed end 120. Each of the four channels 202 is partially formed and adapted to allow the circulation of the cooling fluid.

[0043]

[0044] Accordingly, the stator core 106 includes corresponding partial channels 500, with reference to [Fig. 5] illustrating a zoomed view of the support device 112 disposed between the stator core 106 and the housing 110, which, during assembly, aligns with the channels 202 of the support device 112 to form a conduit through which the cooling fluid is permitted to flow. In other words, the conduit is partially formed on the support device 112 and partially formed on the stator core 106. For the purposes of this disclosure, "assembly" means "disposing the support device 112 in the annular space 114 and the lower surface 402 in contact with the first recess 204." Alternatively, at least one channel 202 is formed as a conduit through the support device 112, thus allowing the cooling fluid to flow through said device 112. Such a conduit in the other example mentioned above is oriented in an axial direction to align with the annular space 114.

[0045] According to an example in this subject, the support device 112 defines at least one flange 200 (also illustrated in [Fig. 2]) formed from the lower surface 402. The at least one flange 200 extends axially towards the closed end 120 of the housing 110. The at least one flange 200 is formed at least partially around the circumference of the lower surface 402. The at least one flange 200 is formed near the inner side 404 of the support device 112. Each of the at least one channel 202 is formed along one of the at least one flange 200, each channel 202 thus extending axially. Furthermore, such an orientation also ensures that the conduit formed by at least one channel 202 is aligned with the annular space 114 so as to facilitate the flow of the cooling fluid.Furthermore, during the assembly of the support device 112, at least one flange 200 is positioned in a second recess 206 (illustrated in [Figs. 2] and 3) formed on the inner surface of the housing 300. The second recess 206 is an undercut formed on the surface of the housing 300. The undercut is formed radially outwards from the axis of rotation 116. The first recess 204 is formed further along the radial direction of the axis of rotation 116 than the second recess 206. In other words, the first recess 204 has an undercut with a greater depth than the second recess 206. The first recess 204 in the examples shown in [Figs. 2] and 3 is formed continuously in a loop on the inner surface of the housing 300. .

[0046] According to an example in this subject, each of the at least one flange 200 is provided with a channel 202. These channels 202 can be partially formed so as to form a conduit with the corresponding partial channels 500 of the stator core 106. Alternatively, these channels 202 form a conduit through the support device 112 through which the cooling fluid can flow.

[0047] In the example where the support device 112 is substantially circular in shape, these flanges 200, by virtue of their axial extension, facilitate indexing during assembly. Furthermore, in this document, the term "indexing" refers to "the error-free alignment of the support device 112 when placed in the annular space 114," a concept also known as "poka-yoke." During the assembly of the support device 112 to the rotating electric machine 100, the flanges 200 are arranged in the second recess 206, and an uninterrupted means of cooling fluid circulation is provided through the channels 202.

[0048] Without limitation, the support device 112, in accordance with this subject, may be formed of an electrically insulating material.

[0049] The present object relates to the application of the rotary electric machine to the automobile, but it is understood that the application can extend to various other industries and can be used in fans, blowers, machine tools, turbines, pumps, compressors, rolling mills, movers, paper mills, etc.

[0050] Various modifications to the disclosed embodiments, as well as to other embodiments of the object, will become apparent to those with relevant knowledge by referring to the description of the object. It is therefore envisaged that such modifications will be made without departing from the scope of this subject.

Claims

Demands

1. Rotating electric machine (100) comprising a rotor rotating about an axis of rotation (116); a stator (104), in coaxial arrangement with the rotor, comprising a stator core (106) and windings (108a; 108b); a housing (110) comprising a chamber (122) defined by a closed end (120) at one end and an open end (118) at the other end, the chamber (122) receiving at least in large part the rotor and the stator (104), in which an inner surface of the housing (300) and an outer surface of the stator core (304) form an annular space (114) extending axially between the two;a support device (112) disposed at least in part between the stator core (106) and the housing (110), said support device (112) covering at least in part the annular space (114) and adapted to at least limit the radial displacement of the stator core (106) with respect to the axis of rotation (116), in which the stator core (106) extends lengthwise along an axial direction, and in which one end of the stator core (106), along the axial direction, is mounted on the housing (110) by fasteners, and the other end is supported by the support device (112).

2. Rotating electric machine (100) according to claim 1, wherein the support device (112) comprises a lower surface (402) facing the closed end (120) of the housing (110) and resting on a first recess (204) formed on the inner surface of the housing (300), wherein the first recess (204) is an undercut formed radially outwards from the axis of rotation (116).

3. Rotating electric machine (100) according to claim 2, wherein the support device (112) comprises at least one channel (202) which is at least partially formed and which extends in an axial direction parallel to the axis of rotation (116).

4. Rotating electric machine (100) according to claim 3, wherein the support device (112) defines at least one flange (200) which extends axially from the lower surface (402) of the support device (112).

5. Rotating electric machine (100) according to claim 4, in which each of the at least one flange (200) is disposed in a second recess (206) formed on the inner surface of the housing (300), the second recess (206) being an undercut formed radially outwards from the axis of rotation (116).

6. Rotating electric machine (100) according to claim 5, in which the first recess (204) is formed further in the radial direction, from the axis of rotation (116), than the second recess (206).

7. Rotating electrical machine (100) according to claim 3, wherein at least one channel (202) is at least partially formed on an internal face (404) of the support device (112).

8. Rotating electric machine (100) according to any one of claims 3 to 6, wherein at least one flange (200) is formed near the inner side (404) and each of the at least one channel (202) is formed along one of the at least one flange (200), wherein the at least one channel (202) extends in the axial direction.

9. Rotating electric machine (100) according to claim 8, wherein the stator core (106) comprises corresponding partial channels (500) which correspond to the at least one channel (202) formed on the support device (112), said at least one channel (202) and the corresponding partial channels (500) forming a conduit configured for the flow of the cooling fluid.

10. Rotating electrical machine (100) according to any one of claims 2 to 8, wherein at least one channel (202) forms a conduit in the support device (112) and the conduit is oriented in the axial direction.

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