Motor and power assembly

Abstract

The invention relates to a motor and a power assembly, and relates to the technical field of motors. The motor comprises a shell and a stator iron core, the motor further comprises two pressing pieces which are oppositely arranged at the two ends of the stator iron core, the two pressing pieces press the stator iron core in the axial direction of the stator iron core, the two pressing pieces are fixedly arranged in the shell, and the outer circumferential wall of the stator iron core is in clearance fit with the inner circumferential wall of the shell. No interaction force exists between the outer circumferential wall of the stator core and the inner circumferential wall of the shell, the sheet structures stacked in the stator core are not prone to deformation or displacement, an oil leakage gap is not prone to being generated between every two adjacent sheet structures, cooling oil is not prone to leaking from the oil leakage gaps to an air gap between a stator and a rotor, and therefore the cooling effect is improved. Therefore, it is ensured that the cooling oil can effectively cool the end portion of the stator winding, so that the possibility of a thermal fault problem of the motor is low.

Description

Technical Field

[0001] This application relates to the technical field of electric motors, and particularly to an electric motor and a powertrain. Background Art

[0002] An electric motor includes a housing and a stator core. The housing surrounds the stator core, and the mating relationship between the housing and the stator core is an interference fit. Through the interference fit, the housing provides a clamping force to the stator to keep the stator core fixed relative to the housing. However, the interference fit relationship between the housing and the stator core is likely to reduce the working reliability of the electric motor. Summary of the Invention

[0003] In view of this, this application provides an electric motor and a powertrain to improve the working reliability of the electric motor.

[0004] In a first aspect, this application provides an electric motor. The electric motor includes a housing and a stator core. The electric motor further includes two pressing members disposed opposite to each other at both ends of the stator core. The two pressing members axially press the stator core along the axial direction of the stator core. The two pressing members are fixedly arranged in the housing, and the outer peripheral wall of the stator core and the inner peripheral wall of the housing are in clearance fit.

[0005] Since both the first pressing member and the second pressing member are fixedly arranged in the housing, that is, both the first pressing member and the second pressing member are fixed relative to the housing. The stator core is axially clamped by the first pressing member and the second pressing member, and the stator core is fixed relative to the first pressing member and the second pressing member, so that the stator core is also fixed relative to the housing. The housing and the stator core are not relatively fixed by an interference fit method, and the mating relationship between the housing and the stator core is a clearance fit.

[0006] In this setting, the inner peripheral wall of the housing and the outer peripheral wall of the stator of the stator core may not exert radial forces on each other. Therefore, the laminated sheet structures in the stator core are not easily deformed or displaced, and it is not easy to generate an oil leakage gap between two adjacent sheet structures, that is, it is not easy for the cooling oil to leak from the oil leakage gap to the air gap between the stator core and the rotor. The cooling oil can flow well along the preset path to both ends of the stator winding of the electric motor, and both ends of the stator winding can be efficiently cooled by the cooling oil meeting the preset flow range, and the possibility of the electric motor having a thermal fault problem is relatively low. At the same time, the sheet structure that is not easily deformed or displaced is not easy to cut the insulating layer of the cable of the nearby stator winding. Therefore, the risk of insulation failure of the electric motor is relatively low.

[0007] As can be seen from the above description, the motor of the present application has high working reliability. In addition, in the present application, since the fitting relationship between the housing and the stator core is a clearance fit, the stator core is not likely to directly transmit the radial vibration effect (the radial vibration generated when the stator core and the stator winding generate electromagnetic excitation) to the housing. Consequently, the radial vibration amplitude of the housing is relatively small, and the housing is not likely to transmit the vibration effect to the fixed structure outside the motor and radiate noise outward through the housing. Therefore, the NVH performance of the motor of the present application is good.

[0008] Optionally, the material of the pressing member is the same as that of the housing.

[0009] Optionally, the material of the pressing member is aluminum alloy.

[0010] Optionally, the pressing member has an annular structure.

[0011] Optionally, the outer peripheral wall of the pressing member is provided with an oil guiding portion and a connecting portion extending along its circumferential direction. The oil guiding portion and the connecting portion are sequentially distributed along the axial direction of the pressing member. Oil spraying holes for spraying cooling oil to the end of the stator winding are evenly spaced along the circumferential direction of the pressing member on the oil guiding portion. The end face of the pressing member close to the oil guiding portion is in close contact with the end face of the stator core to form a seal. The oil guiding portion is communicated with the cooling oil passage on the stator core, and a seal is formed between the connecting portion and the inner peripheral wall of the housing.

[0012] Optionally, the housing is an integrally formed cylindrical structure. At least one end of the housing is provided with an open installation port. A circular first positioning step is formed on the inner peripheral wall of the housing away from the installation port. The end face of the connecting portion of one pressing member is in close contact with the table top of the first positioning step to form a seal, and the circumferential surface of the connecting portion has a clearance fit with the inner peripheral wall of the housing. The other pressing member is arranged close to the installation port.

[0013] Optionally, the circumferential surface of the connecting portion of the pressing member arranged close to the installation port has an interference fit with the inner peripheral wall of the housing to form a seal.

[0014] Optionally, a second positioning step is formed on the inner peripheral wall of the housing close to the installation port. The end face of the connecting portion of the pressing member arranged close to the installation port abuts against the table top of the second positioning step, and the circumferential surface of the connecting portion of the pressing member arranged close to the installation port has a transition fit with the inner peripheral wall of the housing to form a seal.

[0015] Optionally, the second positioning step includes a plurality of bosses evenly spaced along the circumferential direction of the housing, and the bosses are arranged in an adapted manner with the cooling oil passages on the stator core.

[0016] In a second aspect, the present application provides a powertrain for a vehicle. The powertrain of the present application may include the motor described above. The powertrain provided by the present application also includes the technical effects of the motor described above, which will not be elaborated herein.

[0017] It should be understood that the above general description and the following detailed description are merely exemplary and do not limit this application. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of this application, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of this application. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 It is a schematic cross-sectional assembly structure diagram of a motor in the related art, where Figure 1 a housing, a first oil guide ring, a second oil guide ring, a stator core, and a stator winding are shown; Figure 2 It is an exploded structure diagram of a motor in the related art, where Figure 2 a housing, a first oil guide ring, a second oil guide ring, a stator core, a stator winding, and a sealing ring are shown; Figure 3 It is Figure 1 a partial enlarged structure diagram of part A in Figure 4 It is Figure 1 a partial enlarged structure diagram of part B in Figure 5 It is a schematic cross-sectional structure diagram of a stator core in the related art; Figure 6 It is a schematic structure diagram of the motor in the embodiment of this application from a cross-sectional perspective; Figure 7 It is Figure 6 an exploded structure diagram of the motor in Figure 8 It is a schematic cross-sectional structure diagram of the stator core from a cross-sectional perspective; Figure 9 It is Figure 6 a partial enlarged diagram of part C in Figure 10 It is Figure 6 a partial enlarged diagram of part D in Figure 11 It is Figure 7 a schematic structure diagram of the housing in Figure 12 It is a partial cross-sectional structure diagram of the housing, a second pressing member, a stator core, and a stator winding in another embodiment; Figure 13 It is Figure 7 a schematic structure diagram of the stator core in Figure 14 Schematic diagram of the cooperation between the boss of the housing and the cooling oil passage of the stator core in a sectional view; Figure 15 Schematic diagram of the structure of the boss in a sectional view.

[0020] Reference numerals: 101 - Housing; 101a - First sub - housing; 101b - Second sub - housing; 102 - First oil guiding ring; 103 - Stator core; 103a - Laminated structure; 103b - Oil groove; 103c - Air gap; 104 - Second oil guiding ring; 105 - Stator winding; 106 - Sealing ring; 1 - Housing; 11 - Inner peripheral wall; 12 - Mounting opening; 13 - First positioning step; 131 - First table surface; 14 - Second positioning step; 14a - Boss; 141 - Second table surface; 142 - Chamfered surface; 2 - First pressing part; 2a - First outer peripheral wall; 21 - First oil guiding part; 22 - First connecting part; 221 - First circumferential surface; 222 - First positioned end face; 23 - First oil injection hole; 24 - First pressing end face; 3 - Stator core; 3a - Stator outer peripheral wall; 31 - Laminated structure; 32 - Air gap; 33 - Cooling oil passage; 4 - Second pressing part; 4a - Second outer peripheral wall; 41 - Second oil guiding part; 42 - Second connecting part; 421 - Second circumferential surface; 422 - Second positioned end face; 43 - Second oil injection hole; 44 - Second pressing end face; 5 - Stator winding. Specific implementation manner

[0021] In order to better understand the technical solution of the present application, the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0022] It should be clear that the described embodiments are only a part of the embodiments of the present application, rather than all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present application.

[0023] The terms used in the embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to limit the present application. The singular forms of "a", "the" and "said" used in the embodiments of the present application and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise.

[0024] It should be understood that the term " / and / " used herein is only a description of the association relationship of associated objects, indicating that there can be three relationships. For example, a and / or b can represent: a exists alone, a and b exist simultaneously, and b exists alone. In addition, the character " / " herein generally represents an "or" relationship between the front and rear associated objects.

[0025] Please refer to Figure 1 As shown, the motor in the related art includes a housing 101, a first oil guiding ring 102, a stator core 103, a second oil guiding ring 104, and a stator winding 105. Please refer to Figure 2 As shown, the overall structures of the housing 101, the first oil guiding ring 102, the stator core 103, the second oil guiding ring 104, and the stator winding 105 are all annular structures or approximately annular structures.

[0026] Among them, please refer to Figure 1 - Figure 2 As shown, the housing 101 includes a detachable first sub - housing 101a and a second sub - housing 101b, and the first sub - housing 101a and the second sub - housing 101b are arranged along a set direction (a direction parallel to the axis O of the housing 101).

[0027] It should be noted that the axis O of the housing 101 can also be the axis of the first oil guiding ring 102, the axis of the stator core 103, the axis of the second oil guiding ring 104, or the axis of the rotor of the motor (not shown in the figure).

[0028] Please refer to Figure 1As shown, the housing 101 surrounds the first oil guiding ring 102, the stator core 103, the second oil guiding ring 104, and the stator winding 105. The first oil guiding ring 102, the stator core 103, and the second oil guiding ring 104 are arranged along a set direction (the direction parallel to the axis O). In other words, the stator core 103 is located between the first oil guiding ring 102 and the second oil guiding ring 104. The main structure of the stator winding 105 is arranged on the stator core 103. One end of the stator winding 105 is surrounded by the first oil guiding ring 102, and the other end of the stator winding 105 is surrounded by the second oil guiding ring 104.

[0029] It should be noted that since the stator winding 105 includes a plurality of conductive cables, the overall structure of the stator winding 105 is approximately an annular structure. To facilitate clearly showing the overall structure and relative position of the stator winding 105 in the drawings, the overall structure of the stator winding 105 is schematically shown in a simplified manner in the drawings of this article.

[0030] In the related art, the housing 101 is provided with an oil inlet (not marked in the figure). The housing 101, the first oil guiding ring 102, the stator core 103, and the second oil guiding ring 104 enclose an oil guiding channel (not marked in the figure). The first oil guiding ring 102 and the second oil guiding ring 104 are provided with a plurality of oil injection holes (not marked in the figure). The cooling oil outside the motor can flow along Figure 1 the path indicated by the solid black triangular arrow line in the figure, successively passing through the oil inlet, the oil guiding channel, and the oil injection holes. The cooling oil passing through the oil injection holes can flow to the end of the stator winding 105, and the cooling oil can play a good role in cooling the stator core 103 and the stator winding 105 in the working state.

[0031] Please refer to Figure 3 - Figure 4 As shown, in the related art, the motor further includes a plurality of sealing rings 106. The first oil guiding ring 102 can be hermetically connected to the housing 101 through the sealing ring 106. The first oil guiding ring 102 can also be hermetically connected to the stator core 103 through the sealing ring 106. The second oil guiding ring 104 can be hermetically connected to the housing 101 through the sealing ring 106. The second oil guiding ring 104 can also be hermetically connected to the stator core 103 through the sealing ring 106. The above sealing settings can enable the cooling oil to flow along Figure 3 and Figure 4 the path indicated by the solid black triangular arrow line in the figure, successively passing through the oil guiding channel and the oil injection holes, so that the cooling oil can reliably spray from the oil injection holes to the end of the stator winding 105 to cool and lower the temperature of the end of the stator winding 105.

[0032] In the related art, please refer to Figure 5As shown, the stator core 103 includes a plurality of sheet structures 103a, which may also be referred to as metal sheets (such as silicon steel sheets), and the plurality of sheet structures 103a are stacked along the axis O. The outer curved surface wall of the stator core 103 is provided with a plurality of oil grooves 103b, and the extending direction of the oil grooves 103b is parallel to the axis O. The plurality of oil grooves 103b are arranged at intervals along the circumferential direction of the outer curved surface wall of the stator core 103. The cooling oil after passing through the oil inlet of the housing can flow through the oil grooves 103b and along Figure 5 the solid black triangular arrow line in the figure towards the oil injection holes (not shown in the figure).

[0033] In the related art, the mating relationship between the housing 101 and the stator core 103 is an interference fit. The mating surfaces of the housing 101 and the stator core 103 apply radial forces and static frictional forces to each other, so this interference fit can fix the stator core 103 relative to the housing 101 without movement.

[0034] However, the interference fit relationship between the housing 101 and the stator core 103 has the following technical disadvantages: Please refer to Figure 5 As shown, the housing applies a radial force F to the stator core 103, and this radial force F easily causes the sheet structure 103a to deform or displace. If at least one of two adjacent sheet structures 103a deforms or displaces, an oil leakage gap will be generated between the two adjacent sheet structures 103a, and the cooling oil located in the oil groove 103b easily flows from the oil leakage gap to the air gap 103c between the stator core 103 and the rotor (not shown in the figure). The flow rate of the cooling oil flowing towards the oil injection holes will be less than the preset flow rate, and the cooling efficiency of the two end portions of the stator winding arranged at intervals along the axis O is relatively low, and the stator winding is prone to thermal fault problems. The deformed or displaced sheet structure 103a is also prone to cutting the insulation layer of the cable of the nearby stator winding 105, that is, the motor is prone to the risk of insulation failure. Therefore, in the related art, the working reliability of the motor is relatively low.

[0035] Based on the technology of the motor in the related art, on the first aspect, the present application provides some embodiments of an improved motor. Please refer to Figure 6 - Figure 7 As shown, the motor includes a housing 1, a stator core 3, and two pressing members. One pressing member is the first pressing member 2, and the other pressing member is the second pressing member 4. Please refer to Figure 6 As shown, the first pressing member 2 and the second pressing member 4 are located at both ends of the stator core 3. The first pressing member 2 and the second pressing member 4 are fixedly arranged in the housing 1. The first pressing member 2 and the second pressing member 4 press the stator core 3 along the axial direction O1 of the stator core 3, and there is a clearance fit between the outer peripheral wall of the stator core 3 and the inner peripheral wall of the housing 1.

[0036] It should be noted that the axial direction O1 of the stator core 3 can also be the axial direction of the inner peripheral wall 11 of the housing 1 or the axial direction of the rotor of the motor (not shown in the figure).

[0037] In some embodiments, please refer to Figure 6 As shown, since both the first pressing member 2 and the second pressing member 4 are fixedly arranged on the housing 1, that is, both the first pressing member 2 and the second pressing member 4 are stationary relative to the housing 1. The stator core 3 is clamped by the first pressing member 2 and the second pressing member 4 in the axial direction O1, and the stator core 3 is stationary relative to the first pressing member 2 and the second pressing member 4, so that the stator core 3 is also stationary relative to the housing 1. Specifically, please refer to Figure 8 As shown, a force F1 is applied to the stator core 3 by the first pressing member (not shown in the figure), and a force F2 is applied to the stator core 3 by the second pressing member (not shown in the figure). The direction of the force F1 and the direction of the force F2 are both parallel to the axial direction O1, and the direction of the force F1 and the direction of the force F2 are opposite to each other, and the movement of the stator core 3 along the axial direction O1 is restricted. Correspondingly, when there is a tendency of relative movement between the stator core 3 and the first pressing member, a static friction force f1 (a force perpendicular to the axial direction O1) will be generated between the first pressing member and the stator core 3, and / or when there is a tendency of relative movement between the stator core 3 and the second pressing member, a static friction force f2 (a force perpendicular to the axial direction O1) will also be generated between the second pressing member and the stator core 3. The static friction force f1 and the static friction force f2 can limit the rotation of the stator core 3 around the axial direction O1 and the movement along the radial direction (the direction perpendicular to the axial direction O1).

[0038] According to the above, in some embodiments of the present application, the housing 1 and the stator core 3 are not fixed relative to each other by an interference fit, and the fitting relationship between the housing 1 and the stator core 3 is a clearance fit. In this setting, the inner peripheral wall 11 of the housing 1 and the stator outer peripheral wall 3a of the stator core 3 may not exert radial forces (forces perpendicular to the axial direction O1) on each other. Therefore, as Figure 8 shown, the sheet structures 31 stacked along the axial direction O1 in the stator core 3 are not easily deformed or displaced, and it is not easy to generate an oil leakage gap between two adjacent sheet structures 31, that is, it is not easy for the cooling oil to leak from the oil leakage gap to the air gap 32 between the stator core 3 and the rotor (not shown in the figure). The cooling oil can flow well along the preset path to the two ends of the stator winding 5 of the motor shown in Figure 6 at intervals along the axial direction O1. The two ends of the stator winding arranged at intervals along the axial direction O1 can be efficiently cooled by the cooling oil meeting the preset flow rate range, and the possibility of the motor having a thermal fault problem is relatively low. The sheet structure 31 that is not easily deformed or displaced is also not easy to cut the insulating layer of the cable of the nearby stator winding 5. Therefore, the risk of the motor having an insulation failure is relatively low.

[0039] As can be seen from the above description, the operating reliability of the motors in some embodiments of the present application is relatively high.

[0040] In addition, in some embodiments of the present application, since the mating relationship between the housing 1 and the stator core 3 is a clearance fit, the stator core 3 is not likely to directly transmit the radial vibration effect (the radial vibration generated when the stator core and the stator winding generate electromagnetic excitation) to the housing 1. Consequently, the radial vibration amplitude of the housing 1 is relatively small, and the housing 1 is not likely to transmit the vibration effect to the fixed structure outside the motor and radiate noise outward through the housing 1. Therefore, the motors provided in some embodiments of the present application have good NVH performance. It should be noted that NVH performance refers to Noise, Vibration, and Harshness.

[0041] Furthermore, please refer to Figure 8 As shown, each piece structure 31 in the stator core 3 can also withstand reliable acting forces F1 and F2. When there is a tendency of relative movement between two adjacent piece structures 31, the two adjacent piece structures 31 can exert reliable static friction forces on each other. The movement of each piece structure 31 in the stator core 3 along the axial direction O1, rotation around the axial direction O1, and movement in the direction perpendicular to the axial direction O1 are all restricted. In the related art, welding fixation is required between two adjacent piece structures in the stator core. In contrast to the related art, in some embodiments of the present application, welding connection may not be required between all adjacent two piece structures 31 of the stator core 3, so that the piece structure 31 will not generate thermal stress due to the heat generated during the welding process. Therefore, the piece structure 31 is not likely to deform, and it is not easy to generate oil leakage gaps in the stator core 3. Moreover, the structural strength of the piece structure 31 is relatively high, and correspondingly, the structural strength of the stator core 3 is also relatively high. The stator core 3 assembled from multiple piece structures 31 also does not require post-welding treatment (process treatment of the welded parts). As can be seen from the above, in some embodiments of the present application, the manufacturing difficulty of the stator core 3 is relatively low and the required manufacturing time is relatively short. Correspondingly, the manufacturing difficulty of the motor is relatively low and the required manufacturing time is relatively short.

[0042] In some embodiments, before the stator core is installed in the housing, all adjacent two piece structures in the stator core can be pre-fixed by means of snap connection (such as the cooperation of concave-convex structures) or bonding.

[0043] In some embodiments, the clearance fit between the outer peripheral wall 3a (equivalent to the shaft wall) of the stator core 3 and the inner peripheral wall 11 (equivalent to the hole wall) of the housing 1 refers to a fit with a clearance (including a minimum clearance equal to zero). At this time, the tolerance zone of the hole is above the tolerance zone of the shaft, that is, the actual size of the hole is always greater than or equal to the actual size of the shaft. The tolerance zone of the clearance fit can include H7 / f7 or F7 / h6, etc., and the specific tolerance grade is selected according to the assembly situation.

[0044] In some embodiments, the stator core 3 is generally composed of a plurality of sheet structures (such as silicon steel sheets). Although there is a large difference between the expansion coefficient of the housing 1 (2.1E-5 / °C) and the expansion coefficient of the stator core 3 (1.2E-5 / °C), the fit relationship between the housing 1 and the stator core 3 is a clearance fit. During the operation of the motor, even if the temperature of the motor rises, the influence degree of the radial change amplitude of the volume of the housing 1 and the radial change amplitude of the volume of the stator core 3 on the positioning accuracy of the stator core 3 is relatively low, the stator core 3 is not likely to generate a large amplitude of vibration, and the NVH performance of the motor is good.

[0045] In some embodiments of the motor in the present application, the alias of the motor can be a three-phase asynchronous motor, a cage asynchronous motor, a permanent magnet synchronous motor, or an oil-cooled motor.

[0046] In some embodiments, the material of the pressing member can be the same as the material of the housing. In this setting, the thermal expansion coefficient of the pressing member can be the same as the thermal expansion coefficient of the housing. When the temperature of the motor changes, the volume change amplitude of the pressing member and the volume change amplitude of the housing can be the same or close. The fixed connection between the pressing member and the housing is not easily affected, the fixed force between the pressing member and the housing remains unchanged or the change amplitude of the fixed force is relatively small, the pressing member and the housing can still be reliably fixed relative to each other, the stator core can still be reliably pressed by the pressing members at both ends, and the stator core can still be reliably stationary relative to the housing.

[0047] Among them, the material of the housing can include aluminum alloy, and the material of the pressing member can also include aluminum alloy.

[0048] In other embodiments, the material of the housing can also include magnesium alloy. Correspondingly, the material of the pressing member can also be magnesium alloy. Or, the material of the housing can also include cast iron. Correspondingly, the material of the pressing member can also be cast iron.

[0049] In some embodiments, the pressing member may be in a ring structure. For example, the first pressing member 2 may be in a ring structure, and the second pressing member 4 may be in a ring structure. The first pressing end face 24 of the first pressing member 2 is also in a ring shape. When pressing the stator core 3, the acting force exerted by the first pressing end face 24 on the stator core 3 is evenly distributed in the circumferential direction on the stator core 3. Similarly, the second pressing end face 44 of the second pressing member 4 is also in a ring shape. When pressing the stator core 3, the acting force exerted by the second pressing end face 44 on the stator core 3 is evenly distributed in the circumferential direction around the axial direction O1 on the stator core 3. Therefore, the two ends of the stator core 3 are evenly stressed, and the stator core 3 can be more reliably fixed by the first pressing member 2 and the second pressing member 4, so that the stator core 3 can be reliably fixed relative to the housing 1 without movement.

[0050] In some embodiments, the outer peripheral wall of the pressing member is provided with an oil guiding portion and a connecting portion extending along its circumferential direction. The oil guiding portion and the connecting portion are sequentially distributed along the axial direction of the pressing member. The oil guiding portion is evenly spaced along the circumferential direction of the pressing member and is provided with oil spraying holes for spraying cooling oil to the end of the stator winding. The end face of the pressing member close to the oil guiding portion is in close contact with the end face of the stator core to form a seal. The oil guiding portion is communicated with the cooling oil channel on the stator core, and a seal is formed between the connecting portion and the inner peripheral wall of the housing.

[0051] Please refer to Figure 9 As shown in the figure, taking the second pressing member 4 as an example, the second outer peripheral wall 4a of the second pressing member 4 is provided with a second oil guiding portion 41 and a second connecting portion 42 extending along its circumferential direction. The second oil guiding portion 41 and the second connecting portion 42 are sequentially distributed along the axial direction O1 of the second pressing member 4. The second oil guiding portion 41 is evenly spaced along the circumferential direction of the second pressing member 4 and is provided with second oil spraying holes 43 for spraying cooling oil to the end of the stator winding 5. The second oil guiding portion 41 is communicated with the cooling oil channel 33 on the stator core 3, that is, the cooling oil channel 33 is communicated with the second oil spraying holes 43 through the second oil guiding portion 41. Since the material of the second pressing member 4 is the same as that of the housing 1, the rigidity of the second pressing member 4 is relatively large, and the second pressing member 4 is not easily deformed. The end face (the second pressing end face 44) of the second pressing member 4 close to the second oil guiding portion 41 is in close contact with the end face of the stator core 3 to form a reliable seal, and a reliable seal is formed between the second circumferential surface 421 of the second connecting portion 42 and the inner peripheral wall 11 of the housing 1. In this setting, the cooling oil is not easily leaked from between the second pressing end face 44 of the second pressing member 4 and the end face of the stator core 3, and the cooling oil is not easily leaked from between the second circumferential surface 421 of the second connecting portion 42 and the inner peripheral wall 11 of the housing 1. The cooling oil can reliably flow from the cooling oil channel 33 through the second oil guiding portion 41 to the second oil spraying holes 43, so that the cooling oil can reliably spray from the second oil spraying holes 43 to the end of the stator winding 5.

[0052] Compared with the related art where sealing failure is likely to occur due to sealing with a sealing ring, the sealing between the second pressing member 4 with relatively high rigidity and the housing 1 does not rely on a sealing ring, and the sealing reliability between the second pressing member 4 with relatively high rigidity and the housing 1 is relatively high. The sealing between the second pressing member 4 with relatively high rigidity and the stator core 3 also does not rely on a sealing ring, and the sealing reliability between the second pressing member 4 with relatively high rigidity and the stator core 3 is relatively high. Since there is no sealing ring, it is easier to install the second pressing member 4 into the housing 1.

[0053] Please refer to Figure 10 As shown, taking the first pressing member 2 as an example, the first outer peripheral wall 2a of the first pressing member 2 has a first oil guiding portion 21 and a first connecting portion 22 extending along its circumferential direction. The first oil guiding portion 21 and the first connecting portion 22 are sequentially distributed along the axial direction O1 of the first pressing member 2. First spray holes 23 for spraying cooling oil towards the end of the stator winding 5 are evenly spaced along the circumferential direction of the first pressing member 2 on the first oil guiding portion 21. The first oil guiding portion 21 is communicated with the cooling oil channel 33 on the stator core 3, that is, the cooling oil channel 33 is communicated with the first spray holes 23 through the first oil guiding portion 21. Cooling oil can be sprayed from the cooling oil channel 33 towards the end of the stator winding through the first oil guiding portion 21 and the first spray holes 23 in sequence.

[0054] In some embodiments, please refer to Figure 11 As shown, the housing 1 is an integrally formed cylindrical structure. At least one end of the housing 1 is open to form an installation opening 12. An annular first positioning step 13 as shown in Figure 10 is formed on the inner peripheral wall 11 of the housing 1 away from the installation opening 12. Since the material of the first pressing member 2 is the same as that of the housing 1, the first pressing member 2 has relatively high rigidity and is not easily deformed. The first positioned end face 222 of the first connecting portion 22 of the first pressing member 2 is in close contact with the first table surface 131 of the first positioning step 13 to form a seal. The end face (the first pressing end face 24) of the first pressing member 2 close to the first oil guiding portion 21 is in close contact with the end face of the stator core 3 to form a reliable seal. In this setting, cooling oil is not easily leaked from between the first pressing end face 24 of the first pressing member 2 and the end face of the stator core 3, and cooling oil is not easily leaked from between the first positioned end face 222 of the first connecting portion 22 and the first table surface 131 of the first positioning step 13. Cooling oil can reliably flow from the cooling oil channel 33 through the first oil guiding portion 21 to the first spray holes 23, so that cooling oil can reliably be sprayed from the first spray holes 23 towards the end of the stator winding 5.

[0055] Compared with the related art where sealing failure is likely to occur due to sealing with a sealing ring, the sealing between the relatively rigid first pressing member 2 and the housing 1 does not rely on a sealing ring, and the sealing reliability between the relatively rigid first pressing member 2 and the housing 1 is relatively high. The sealing between the relatively rigid first pressing member 2 and the stator core 3 also does not rely on a sealing ring, and the sealing reliability between the relatively rigid first pressing member 2 and the stator core 3 is relatively high. Since there is no sealing ring, it is easier to install the first pressing member 2 into the housing 1.

[0056] In some embodiments, please refer to Figure 11 As shown, since the housing 1 is an integrally formed cylindrical structure, the first pressing member 2 and the second pressing member 4 are both fixed to the integrally formed housing 1. The rigidity of the component structure among the housing 1, the first pressing member 2, the stator core 3, and the second pressing member 4 is relatively large, and the housing 1, the first pressing member 2, the stator core 3, and the second pressing member 4 are not likely to loosen relative to each other casually.

[0057] Please refer to Figure 10 As shown, the first circumferential surface 221 of the first connecting portion 22 of the first pressing member 2 is in clearance fit with the inner peripheral wall 11 of the housing 1. In this setting, it is convenient to install the first pressing member 2 into the housing 1 from outside the housing 1 through the installation opening 12, and the assembly difficulty of the first pressing member 2 and the housing 1 is relatively low.

[0058] Since the outer peripheral wall 3a of the stator of the stator core 3 is also in clearance fit with the inner peripheral wall 11 of the housing 1, after assembling the first pressing member 2 and the housing 1, the stator core 3 can be installed into the housing 1 from outside the housing 1 through the installation opening 12, and the assembly difficulty of the stator core 3 and the housing 1 is relatively low.

[0059] After assembling the stator core 3 and the housing 1, the second pressing member 4 can be installed into the housing 1 from outside the housing 1 through the installation opening 12, and the second pressing member 4 is made to be close to the installation opening 12.

[0060] According to the above content, the assembly difficulty of the housing 1, the first pressing member 2, the stator core 3, and the second pressing member 4 is relatively low.

[0061] In some embodiments, please refer to Figure 9 As shown, a second positioning step 14 is formed on the inner peripheral wall 11 of the housing 1 near the installation opening 12. The end face (the second positioned end face 422) of the second connecting portion 42 of the second pressing member 4 disposed near the installation opening 12 abuts against the second table surface 141 of the second positioning step 14, and the second table surface 141 can limit the movement of the second pressing member 4 in the direction away from the stator core 3, so that the second pressing member 4 reliably presses the stator core 3.

[0062] In some embodiments, please refer to Figure 9As shown, the second circumferential surface 421 of the second connecting portion 42 of the second pressing member 4 disposed near the mounting port 12 and the inner peripheral wall 11 of the housing 1 are in transitional fit to form a seal.

[0063] In some embodiments, please refer to Figure 12 As shown, the second circumferential surface 421 of the second connecting portion 42 of the second pressing member 4 disposed near the mounting port 12 and the inner peripheral wall 11 of the housing 1 may form a seal by interference fit. Correspondingly, a second positioning step may not be formed on the inner peripheral wall 11 of the housing 1 near the mounting port 12.

[0064] In some embodiments, if the weight of the stator core is relatively large and the inertial force of the stator is relatively large during vibration and shock, then as Figure 9 shown, the second pressing member 4 and the housing 1 not only fix the second pressing member 4 relative to the housing 1 by transitional fit, but the second pressing member 4 also needs to be axially positioned by the second positioning step 14 of the housing 1 on the axis O1.

[0065] In some embodiments, if the weight of the stator core is relatively small and the inertial force of the stator core is relatively small during vibration and shock, then as Figure 12 shown, the second pressing member 4 and the housing 1 may fix the second pressing member 4 relative to the housing 1 by interference fit.

[0066] In some embodiments, please refer to Figure 11 As shown, the second positioning step 14 may include a plurality of bosses 14a evenly spaced along the circumferential direction of the housing 1. Please refer to Figure 13 As shown, a plurality of cooling oil channels 33 are provided on the stator outer peripheral wall 3a of the stator core 3. The plurality of cooling oil channels 33 extend along the axis O1, and the plurality of cooling oil channels 33 are spaced at intervals along the circumferential direction of the stator outer peripheral wall 3a of the stator core 3. Please refer to Figure 14 As shown, the bosses 14a are arranged in adaptation with the cooling oil channels 33. In this setting, when the stator core 3 is inserted into the housing 1 from outside the housing 1 through the mounting port 12, the cooling oil channels 33 can avoid the bosses 14a, and no structural interference will occur between the stator core 3 and the housing 1.

[0067] In some embodiments, please refer to Figure 15As shown, the boss 14a has a set height dimension H (the dimension perpendicular to the axial direction O1), and the height dimension H is in the range of 0.01mm~0.19mm. The height dimension H can specifically be 0.01mm, 0.02mm, 0.03mm, 0.04mm, 0.05mm, 0.06mm, 0.07mm, 0.08mm, 0.09mm, 0.1mm, 0.11mm, 0.12mm, 0.13mm, 0.14mm, 0.15mm, 0.16mm, 0.17mm, 0.18mm or 0.19mm. When the second clamping piece is installed into the shell through the installation opening from the outside of the shell, the second clamping piece and the boss 14a will squeeze each other and elastically deform. When the second clamping piece moves to the side of the second table 141 of the boss 14a close to the stator core, the second clamping piece and the boss 14a will both be restored, so that the second circumferential surface 421 of the second connecting portion 42 of the second clamping piece 4 forms a transition fit with the inner circumferential wall 11 of the shell 1, and the second positioned end face 422 of the second connecting portion 42 of the second clamping piece 4 abuts against the second table 141 of the second positioning step 14.

[0068] In some embodiments, the second pressing member can be directly installed into the housing 1 at room temperature (eg, 10°C to 30°C). This assembly method is relatively easy and takes relatively short time. Of course, the second pressing member can also be installed into the housing 1 by cold assembly.

[0069] In some embodiments, the boss 14a includes a chamfered surface 142, which is located on the side of the boss 14a away from the second platform 141. The chamfered surface 142 can guide the second pressing member so that the second pressing member can be smoothly installed into the housing through the installation opening from outside the housing.

[0070] It should be noted that, in some embodiments of the present application, the electric motor may also include a rotor, an end cover, a bus bar, an external terminal, a rectifier, a bearing, a bearing pressure plate, a magnetic steel, a conductive spring and other structures.

[0071] In some embodiments of the present application, the electric motor may be applied to various devices that need to convert electrical energy into kinetic energy, such as vehicles, ships, aircraft, or towing devices.

[0072] In a second aspect, an embodiment of the present application provides a powertrain, which may include the motor described in the above embodiment. Accordingly, the powertrain may include the technical effects of the motor described in the above embodiment, which will not be repeated here.

[0073] The powertrain may further include at least one of a hybrid case, a reducer, a clutch, a differential and an engine.

[0074] In a third aspect, an embodiment of the present application provides a vehicle, which may include the electric motor described in the above embodiments. Alternatively, the vehicle may include the powertrain described in the above embodiments. Correspondingly, the vehicle may also include the technical effects of the electric motor described in the above embodiments, which will not be elaborated herein.

[0075] Divided by power type, the vehicle may be a hybrid vehicle or a pure electric vehicle.

[0076] Divided by structural type, the vehicle may be a sedan, a truck, an all-terrain vehicle, a tricycle, a two-wheeler, a tractor or an engineering vehicle, etc.

[0077] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. For those skilled in the art, the present application may have various modifications and changes. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included within the protection scope of the present application.

Claims

1. An electric motor, comprising a housing and a stator core, characterized in that: The electric motor further comprises: Two pressing members are arranged opposite to each other at two ends of the stator core; The two pressing members press the stator core axially, and the two pressing members are fixedly arranged in the housing; The outer peripheral wall of the stator core and the inner peripheral wall of the housing are clearance-matched.

2. The electric motor according to claim 1, characterized in that The material of the pressing member is the same as that of the shell.

3. The electric motor according to claim 2, characterized in that The material of the pressing piece is aluminum alloy.

4. The electric motor according to claim 1, characterized in that The pressing piece is in an annular structure.

5. The electric motor according to claim 4, characterized in that The outer peripheral wall of the clamping piece is provided with an oil guide portion and a connecting portion extending in the circumferential direction thereof, the oil guide portion and the connecting portion are sequentially distributed along the axial direction of the clamping piece, and the oil guide portion is provided with oil spray holes evenly spaced along the circumferential direction of the clamping piece for spraying cooling oil to the stator winding end; The end surface of the pressing member close to the oil guide portion is tightly fitted with the end surface of the stator core to form a seal, and the oil guide portion is connected to the cooling oil channel on the stator core; A seal is formed between the connecting portion and the inner peripheral wall of the housing.

6. The electric motor according to claim 5, characterized in that The shell is an integrally formed cylindrical structure, at least one end of the shell is open to form a mounting opening, and an annular first positioning step is formed on the inner peripheral wall of the shell away from the mounting opening; The end surface of the connecting portion of one of the pressing members is tightly fitted with the table surface of the first positioning step to form a seal, and the circumferential surface of the connecting portion is gap-fitted with the inner circumferential wall of the shell; Another pressing member is arranged close to the installation opening.

7. The electric motor according to claim 6, characterized in that The circumferential surface of the connecting portion of the pressing piece arranged near the installation opening is interference-fitted with the inner circumferential wall of the shell to form a seal.

8. The electric motor according to claim 6, characterized in that A second positioning step is formed on the inner peripheral wall of the housing near the mounting opening; The end surface of the connecting portion of the pressing member disposed near the installation opening abuts against the table surface of the second positioning step; The circumferential surface of the connecting portion of the pressing piece arranged near the installation opening is transitionally matched with the inner circumferential wall of the shell to form a seal.

9. The electric motor according to claim 8, characterized in that The second positioning step includes a plurality of bosses evenly spaced and distributed along the circumference of the housing, and the bosses are matched with the cooling oil channels on the stator core.

10. A powertrain for a vehicle, characterized in that: The powertrain includes the electric motor according to any one of claims 1 to 9.

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