Stator assembly, electric motor, electric drive system and vehicle

Abstract

The present disclosure relates to a stator assembly, the stator assembly comprising: a stator main body (10), the stator main body (10) having a first end and a second end in an electric motor axial direction; an oil guide ring (11), the oil guide ring (11) being arranged on the first end and the second end, and an edge of the oil guide ring (11) that is near the stator main body (10) having a stepped structure (111); and a sealing member (12), the sealing member (12) being approximately annular, and the sealing member (12) being mounted on the stepped structure (111) of the oil guide ring (11) and fitted to the stepped structure (111), for axially sealing the stator assembly, and the sealing member (12) comprising an inner frame (121) made of a first material and a covering layer (122) made of a second material, the covering layer (122) covering the inner frame (121) The present disclosure further relates to an electric motor, an electric drive system and a vehicle that comprise such a stator assembly.

Description

[0001] STATOR ASSEMBLY, ELECTRIC MOTOR, ELECTRIC DRIVE SYSTEM AND VEHICLE

[0002] TECHNICAL FIELD

[0003] The present disclosure relates to a stator assembly. In particular, the stator assembly according to the present disclosure may absorb more axial tolerance and has a better axial sealing effect. The present disclosure further relates to an electric motor, an electric drive system and a vehicle that comprise such a stator assembly.

[0004] BACKGROUND

[0005] Generally, an electric motor comprises a stator, the stator comprising a stator main body and oil guide rings; the stator main body has a first end face and a second end face in an axial direction, and the oil guide rings are arranged on the first end face and the second end face, and the oil guide rings surround end windings at both ends of the stator main body. The oil guide ring is an annular structure, and is provided with flow-guiding holes for example. When the electric motor is running, a cooling medium (such as oil) is constantly sprayed out of the flow-guiding holes and applied to the end windings at the first end face and the second end face of the stator to cool the end windings.

[0006] A means for sealing the oil guide ring comprises axial sealing and radial sealing, and generally an O-ring is used for sealing. Regarding a radial sealing means, in the process of mounting an electric motor housing, there may be a risk of cutting the sealing ring, thereby damaging the sealing ring. Regarding an axial sealing means, a manufacturing error of stator encapsulation length results in more axial tolerance, and an O-ring is poor at absorbing axial tolerance. In addition, some electric motors have ear-shaped outer extension portions that extend radially, and these outer extension portions allow fastening members to pass through; O- rings do not fit the shape of this type of electric motor, and are unable to provide good sealing.

[0007] Thus, there is an urgent need to provide a novel stator assembly, which is able to absorb more axial tolerance and has a better axial sealing effect. SUMMARY OF THE INVENTION

[0008] Thus, the present disclosure is intended to solve the abovementioned problem, having the objective of providing a novel stator assembly, an electric motor, an electric drive system and a vehicle.

[0009] The objective is achieved by means of providing a stator assembly according to an embodiment of the present disclosure, the stator assembly comprising: a stator main body, the stator main body having a first end and a second end in an axial direction; an oil guide ring, the oil guide ring being arranged on the first end and the second end, and an edge of the oil guide ring that is near the stator main body having a stepped structure; and a sealing member, the sealing member being approximately annular, and the sealing member being mounted on the stepped structure of the oil guide ring and fitted to the stepped structure, for axially sealing the stator assembly, and the sealing member comprising an inner frame made of a first material and a covering layer made of a second material, the covering layer covering the inner frame.

[0010] One of the objectives of the present disclosure lies in providing a stator assembly, which is able to absorb more axial tolerance and has a better axial sealing effect.

[0011] The stator assembly according to the present disclosure may also have one or more of the following features, alone or in combination.

[0012] According to an embodiment of the present disclosure, the first material comprises plastic or steel, and the second material comprises rubber.

[0013] According to an embodiment of the present disclosure, the oil guide ring comprises multiple outer extension portions that extend radially, and the sealing member is correspondingly provided with multiple ear-shaped structures for fitting to the outer extension portions.

[0014] According to an embodiment of the present disclosure, the outer extension portion of the oil guide ring is provided with a through hole for a fastener to pass through, and the fastener extends axially from the oil guide ring located at the first end to the oil guide ring located at the second end. According to an embodiment of the present disclosure, the stator assembly further comprises an end winding, the end winding being arranged at the first end and the second end of the stator main body, and the oil guide ring surrounding the end winding, and the oil guide ring is provided with at least one cooling channel, the cooling channel comprising a cooling inlet and a cooling outlet, the cooling inlet being located on a surface of the stepped structure that is perpendicular to the axial direction, and the cooling outlet being located on a surface of the oil guide ring that faces the end winding.

[0015] According to an embodiment of the present disclosure, the surface of the oil guide ring that faces the end winding comprises an inclined face that is inclined relative to the axial direction, and the cooling outlet is located on the inclined face.

[0016] The present disclosure further relates to an electric motor, which comprises the stator assembly described above and a housing, the housing comprising a housing wall that defines an accommodating space, the stator assembly being accommodated in the accommodating space.

[0017] According to an embodiment of the present disclosure, the housing wall and the stepped structure of the oil guide ring form a first space, and the sealing member is arranged in the first space.

[0018] According to an embodiment of the present disclosure, the size of the sealing member in the axial direction is larger than the size of the first space in the axial direction.

[0019] According to an embodiment of the present disclosure, the housing wall and a surface of the stator main body form a cavity, the cooling inlet being in fluid communication with the cavity, a cooling liquid flowing through the cooling inlet and into the oil guide ring from the cavity, and being sprayed onto the end winding from the cooling outlet.

[0020] The present disclosure further relates to an electric drive system, which comprises the electric motor described above.

[0021] The present disclosure further relates to a vehicle, which comprises the electric drive system described above. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] The foregoing and other features and advantages of the present disclosure will become more apparent from the following detailed description of exemplary embodiments with reference to the accompanying drawings, and the description and the accompanying drawings are for illustrative purposes only and are not intended to limit the scope of the present disclosure in any way. The drawings below are not drawn to scale according to actual dimensions but rather focus on showing the main purpose of the present disclosure.

[0023] Fig. 1 shows a sectional schematic drawing of a portion of an electric motor provided by at least one embodiment of the present disclosure;

[0024] Fig. 2 shows a detailed view of the area labelled B in Fig. 1 ;

[0025] Fig. 3 shows a structural schematic drawing of an oil guide ring provided by at least one embodiment of the present disclosure;

[0026] Fig. 4 shows a structural schematic drawing of a sealing ring provided by at least one embodiment of the present disclosure;

[0027] Fig. 5 shows a sectional schematic drawing of a sealing ring provided by at least one embodiment of the present disclosure.

[0028] DETAILED DESCRIPTION

[0029] To clarify the objective, technical solutions and advantages of embodiments of the present disclosure, the technical solutions of the embodiments of the present disclosure are described clearly and completely below in conjunction with the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are some rather than all of the embodiments of the present disclosure.

[0030] Unless defined otherwise, the technical or scientific terms used herein shall have the common meanings as understood by those of ordinary skill in the field to which the present disclosure belongs. Words such as "one", "a" or "the" used in the description and the claims of the patent application disclosed herein do not indicate a quantity limit, but mean that there is at least one. Words such as "comprise" or "include" mean that the element or object appearing before the word encompasses the elements or objects and their equivalents listed after the word, without excluding other elements or objects. Words such as "first" and "second" used in the description and claims of the patent application disclosed herein do not denote any order, quantity or importance, and are merely used to distinguish different component parts. The terms “upper”, “lower”, “left”, “right” and the like are only used to indicate a relative positional relationship, and when the absolute position of a described object changes, the relative positional relationship may also change accordingly.

[0031] Embodiments according to the present disclosure are described in detail with reference to the drawings. It must be noted here that in the drawings, identical reference numerals are assigned to component parts having substantially the same or similar structures and functions, and repeated descriptions of such component parts are omitted.

[0032] It must be explained that the direction “axial direction” is understood to refer to a direction along or parallel to the axis of rotation of the electric motor in the present disclosure. The direction “radial direction” is understood to refer to a direction perpendicular to the axis of rotation of the electric motor.

[0033] Fig. 1 shows a sectional schematic drawing of a portion of an electric motor provided by at least one embodiment of the present disclosure.

[0034] As shown in Fig. 1, the electric motor comprises a stator assembly and a housing, the housing comprising a housing wall 14 that defines an accommodating space, the stator assembly being accommodated in the accommodating space. The stator assembly comprises a stator main body 10, an oil guide ring 11, a sealing member 12 and an end winding 13. The stator main body 10 is formed by stacking multiple laminations, and has a first end and a second end in an axial direction, and the end winding 13 is arranged on the first end and the second end of the stator main body 10. The oil guide ring 11 is arranged on the first end and the second end of the stator main body 10, and the oil guide ring 11 surrounds the end winding 13.

[0035] Reference can be made to Figs. 3 and 4 for the specific structures of the oil guide ring 11 and the sealing member 12.

[0036] Fig. 2 shows a detailed view of the area labelled B in Fig. 1.

[0037] As shown in Fig. 2, an edge of the oil guide ring 11 that is near the stator main body 10 is provided with a stepped structure 111, and the sealing member 12 is mounted on the stepped structure 111 of the oil guide ring 11 and fitted to the stepped structure 111, for axially sealing the stator assembly.

[0038] As shown in Fig. 2, the housing wall 14 and the stepped structure 111 of the oil guide ring 11 form a first space 15, and the sealing member 12 is arranged in the first space 15.

[0039] As shown in Fig. 2, the oil guide ring 11 is provided with at least one cooling channel 113, the cooling channel 113 comprising a cooling inlet 1131 and a cooling outlet 1132, the cooling inlet 1131 being located on a surface of the stepped structure 111 that extends radially, and the cooling outlet 1132 being located on a surface of the oil guide ring 11 that faces the end winding 13.

[0040] Cooling liquid may first enter a cavity that is formed by the housing wall 14 and a surface of the stator main body 10, the cooling inlet 1131 of the cooling channel 113 being in fluid communication with the cavity, and the cooling liquid may then flow through the cooling inlet 1131 and into the cooling channel 113 of the oil guide ring 11 from the cavity, and is sprayed onto the end winding 13 from the cooling outlet 1132 of the cooling channel 113.

[0041] For example, in some embodiments of the present disclosure, the surface of the oil guide ring 11 that faces the end winding 13 comprises an inclined face that is inclined relative to the axial direction, and the cooling outlet 1132 is located on this inclined face. In order to better cool the end winding, cooling liquid is preferably sprayed near the centre of the end winding. In this embodiment, since the size of the oil guide ring is narrower in the axial direction, the cooling liquid is not easily sprayed to an appropriate position on the end winding; therefore, a portion of the surface of the oil guide ring that faces the end winding is configured as an inclined face, and cooling liquid can therefore be sprayed at an incline to an appropriate position on the end winding, and the cooling effect is better. As shown in Fig. 2, the cooling channel 113 comprises a first channel portion that extends in the axial direction and a second channel portion that is inclined relative to the axial direction. Preferably, the second channel portion is perpendicular to the inclined face of the oil guide ring. It must be explained that the present disclosure imposes no restrictions on the structure of the cooling channel 113; all that is necessary is for a better cooling effect to be achievable.

[0042] It can be seen from Fig. 2 that when cooling liquid flows from the surface of the stator main body 10 into the oil guide ring 11, the sealing member 12 that is located on the stepped structure 111 may prevent the cooling liquid from flowing out of a gap between the housing and the oil guide ring, thus reducing wastage of the cooling liquid, such that as much cooling liquid as possible is used for cooling the end winding.

[0043] Fig. 3 shows a structural schematic drawing of an oil guide ring 11 provided by at least one embodiment of the present disclosure.

[0044] As shown in Fig. 3, the oil guide ring 11 comprises multiple outer extension portions 112 that extend radially, the outer extension portion 112 of the oil guide ring 11 is provided with a through hole 1121 for a fastener to pass through, and the fastener extends axially from the oil guide ring located at the first end to the oil guide ring located at the second end. For example, the stator main body 10 also comprises multiple outer extension portions that extend radially, and the oil guide ring located at the first end, the oil guide ring located at the second end and the stator main body may be assembled together with fasteners.

[0045] As shown in Fig. 3, an edge of the oil guide ring 11 is provided with a stepped structure 111; this stepped structure 111 extends along the shape of an outer edge of the oil guide ring 11 at a radial inner side of the outer edge of the oil guide ring 11, and stops at an outer extension portion 112 of the oil guide ring 11. An outer surface of the stepped structure 111 that extends in the axial direction fits to the sealing member 12, an inner surface of the stepped structure 111 that extends in the axial direction is fitted around the stator main body 10, and multiple cooling inlets 1131 are provided on a surface of the stepped structure 111 that extends in a radial direction.

[0046] Fig. 4 shows a structural schematic drawing of a sealing member 12 provided by at least one embodiment of the present disclosure.

[0047] As shown in Fig. 4, the sealing member 12 is approximately annular, and, in order to fit to the outer extension portions 112 of the oil guide ring 11, the sealing member 12 is correspondingly provided with multiple ear-shaped structures 123.

[0048] By means of correspondingly providing multiple ear-shaped structures 123 on the sealing member 12, the sealing member provided by embodiments of the present disclosure is able to better fit to the shape of the oil guide ring 11, and can achieve a better sealing effect compared to an O-ring.

[0049] Fig. 5 shows a sectional schematic drawing of a sealing member 12 provided by at least one embodiment of the present disclosure.

[0050] As shown in Fig. 5, the sealing member 12 comprises an inner frame 121 made of a first material and a covering layer 122 made of a second material, the covering layer 122 covering the inner frame 121.

[0051] For example, in some embodiments of the present disclosure, the inner frame

[0052] 121 is made of plastic or steel, and the covering layer 122 is made of rubber. It must be explained that another material, such as aluminium, may further be used for the inner frame 121, and another material, such as resin, may further be used for the covering layer 122; the present disclosure imposes no restrictions on the materials of the inner frame 121 and the covering layer 122.

[0053] The inner frame 121 of the sealing member 12 may be moulded into various shapes, so as to be able to fit to the structure of the oil guide ring 11, achieving a better sealing effect. Moreover, due to the use of the inner frame 121, the cross section of the sealing member 12 is larger than the cross section of a normal O-ring seal, and therefore, compared with an O-ring seal, the sealing member provided by embodiments of the present disclosure has a larger size in the axial direction, which may absorb more axial tolerance, achieving a better sealing effect.

[0054] A more flexible type of material, such as rubber, is used for the covering layer

[0055] 122 of the sealing member 12, and the size of the sealing member 12 in the axial direction is larger than the size of the first space 15 in the axial direction. Therefore, after assembly of an electric motor is completed, the sealing member 12 is compressed in the axial direction, and the sealing member 12 is compressed by the oil guide ring 11 and the electric motor housing in the first space 15, thereby achieving axial sealing.

[0056] According to another aspect of the present disclosure, an electric drive system is proposed, comprising the electric motor as described above. It should be understood that the electric drive system of the present disclosure also has the advantages described above in relation to the stator assembly.

[0057] According to another aspect of the present disclosure, a vehicle is provided, comprising the electric drive system as described above. The vehicle may be an electrified vehicle, such as a battery electric vehicle (BEV), a hybrid electric vehicle (HEV), a plug-in hybrid electric vehicle (PHEV), a range extended EV or a fuel cell electric vehicle (FCEV). The vehicle may also be a hydrogen-powered vehicle. It should be understood that the vehicle of the present disclosure also has the advantages described above in relation to the stator assembly.

[0058] Certain features, structures or characteristics in one or more embodiments of the present disclosure may be combined appropriately.

[0059] The above is a description of the present disclosure and should not be considered as a limitation thereof. Although some exemplary embodiments of the present disclosure have been described, those skilled in the art will readily understand that many modifications could be made to the exemplary embodiments without departing from the original teaching and advantages of the present disclosure. Therefore, all such modifications are intended to be included in the scope of the present disclosure as defined by the claims. It should be understood that the above is an explanation of the present disclosure and the present disclosure should not be considered to be limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments and other embodiments are intended to be included within the scope of the present disclosure.

Claims

WHAT IS CLAIMED IS:

1. A stator assembly, characterized in that the stator assembly comprises: a stator main body (10), wherein the stator main body (10) has a first end and a second end in an axial direction; an oil guide ring (11), wherein the oil guide ring (11) is arranged on the first end and the second end, and an edge of the oil guide ring (11) that is near the stator main body (10) has a stepped structure (111); and a sealing member (12), wherein the sealing member (12) is approximately annular, and the sealing member (12) is mounted on the stepped structure (111) of the oil guide ring (11) and fitted to the stepped structure (111), for axially sealing the stator assembly, wherein the sealing member (12) comprises an inner frame (121) made of a first material and a covering layer (122) made of a second material, and the covering layer (122) covers the inner frame (121).

2. The stator assembly according to Claim 1, characterized in that the first material comprises plastic or steel, and the second material comprises rubber.

3. The stator assembly according to Claim 1, characterized in that the oil guide ring (11) comprises multiple outer extension portions (112) that extend radially, and the sealing member (12) is correspondingly provided with multiple ear-shaped structures (123) for fitting to the outer extension portions (112).

4. The stator assembly according to Claim 3, characterized in that the outer extension portion (112) of the oil guide ring (11) is provided with a through hole (1121) for a fastener to pass through, and the fastener extends axially from the oil guide ring located at the first end to the oil guide ring located at the second end.

5. The stator assembly according to Claim 1, characterized in that the stator assembly further comprises an end winding (13), and the end winding (13) is arranged on the first end and the second end of the stator main body (10), and the oil guide ring (11) surrounds the end winding (13), wherein the oil guide ring (11) is provided with at least one cooling channel (113), and the cooling channel (113) comprises a cooling inlet (1131) and a cooling ioutlet (1132), and the cooling inlet (1131) is located on a surface of the stepped structure (111) that extends radially, and the cooling outlet (1132) is located on a surface of the oil guide ring (11) that faces the end winding (13).

6. The stator assembly according to Claim 5, characterized in that the surface of the oil guide ring (11) that faces the end winding (13) comprises an inclined face that is inclined relative to the axial direction, and the cooling outlet (1132) is located on the inclined face.

7. An electric motor, characterized in that the electric motor comprises the stator assembly according to any one of Claims 1 - 6 and a housing, and the housing comprises a housing wall (14) that defines an accommodating space, and the stator assembly is accommodated in the accommodating space.

8. The electric motor according to Claim 7, characterized in that the housing wall (14) and the stepped structure (111) of the oil guide ring (11) form a first space (15), and the sealing member (12) is arranged in the first space (15).

9. The electric motor according to Claim 8, characterized in that the size of the sealing member (12) in the axial direction is larger than the size of the first space (15) in the axial direction.

10. The electric motor according to Claim 7, characterized in that the housing wall (14) and a surface of the stator main body (10) form a cavity, and the cooling inlet (1131) is in fluid communication with the cavity, and cooling liquid flows through the cooling inlet (1131) and into the oil guide ring (11) from the cavity, and is sprayed onto the end winding (13) from the cooling outlet (1132).

11. An electric drive system, characterized in that the electric drive system comprises the electric motor according to any one of Claims 7 to 10.

12. A vehicle, characterized in that the vehicle comprises the electric drive system according to Claim 11.

Images