Motor, power assembly and vehicle

Abstract

The invention provides a motor, a power assembly and a vehicle, and relates to the field of electric vehicles, and the motor comprises a motor shell and a plurality of stator cores. And the winding slots of each stator core are arranged along the circumferential direction of the motor. The plurality of stator iron cores comprise two first stator iron cores and a second stator iron core, and the second stator iron core is arranged between the two first stator iron cores along the axial direction of the motor. The second stator iron core, the two first stator iron cores and the motor shell form a first gap. One opening of one first through hole and one opening of the other first through hole in each first stator iron core in the axial direction of the motor are exposed in the first gap, and the maximum distance between one first through hole and the axis of the motor in the radial direction of the motor is smaller than the minimum distance between the other first through hole and the axis of the motor. The cooling efficiency of the motor can be improved by adjusting the flow channels of the stator cores, and normal running of a vehicle is ensured.

Description

Technical Field

[0001] The present application relates to the technical field of electric vehicles, and in particular to a motor, a powertrain and a vehicle. Background Art

[0002] In the new energy vehicle industry, as electric vehicles continue to develop towards high power density, the heat generated by the motor during operation is gradually increasing. In order to control the temperature rise of the motor, it is necessary to cool the stator core and windings of the motor to avoid excessive temperature affecting the motor efficiency. However, the current heat dissipation solution for the motor has the problem of low cooling efficiency, which is not conducive to improving the efficiency and service life of the motor, and will also have a negative impact on the normal driving of the vehicle. Summary of the invention

[0003] Embodiments of the present application provide a motor, a powertrain, and a vehicle that can improve cooling efficiency.

[0004] In a first aspect, an embodiment of the present application provides a motor, which includes a motor housing and multiple stator cores, wherein the motor housing is used to accommodate the multiple stator cores, and the multiple winding slots of each stator core are arranged in sequence along the circumference of the motor, and each winding slot is used to accommodate multiple wires, and the multiple stator cores include two first stator cores and one second stator core.

[0005] Each first stator core includes a plurality of first through holes, which penetrate each first stator core along the axial direction of the motor, and the plurality of first through holes of each first stator core are spaced apart from the plurality of winding slots of each first stator core.

[0006] A second stator core is arranged between the two first stator cores along the axial direction of the motor.

[0007] At least a portion of the outer circumference of a second stator core forms a first gap with two first stator cores and a motor housing. An opening of a first through hole in each first stator core and an opening of another first through hole are exposed to a first gap along the axial direction of the motor. The maximum distance between each first through hole and the axis of the motor along the radial direction of the motor is smaller than the minimum distance between another first through hole and the axis of the motor.

[0008] In the embodiment of the present application, when the motor is in working state, the alternating current passing through the multiple wires of the motor will cause resistance loss. The alternating magnetic flux generated after the wires are energized will also cause hysteresis loss and eddy current loss in the multiple stator cores, causing the heat generated by the stator core and winding to continue to increase.

[0009] In an embodiment of the present application, each first stator core includes a first through hole and another first through hole. The distances between the first through hole and the axis of the motor are different along the radial direction of the motor. By supplying coolant to the first through hole and the other first through hole, the heat dissipation effect on the stator core and the winding slot can be taken into account, thereby realizing multi-level cooling in the motor.

[0010] In an embodiment of the present application, a first through hole and another first through hole are spaced apart so that the first through hole and the other first through hole form two parallel flow channels in a single first stator core. In order to deliver the coolant to the first through hole and the other first through hole of each first stator core, the embodiment of the present application utilizes at least a portion of the outer circumference of a second stator core to form a first gap with the two first stator cores and the inner circumference of the motor housing, and an opening of the first through hole and the other first through hole of each first stator core is exposed to the first gap, so that the coolant delivered by the inner circumference of the motor housing can flow to the first through hole and the other first through hole of the two first stator cores respectively through the first gap, which is conducive to reducing the loss of the coolant in the transmission path of each first stator core.

[0011] Taking a first through hole as an example, an opening of a first through hole is exposed to the first gap, which means that an opening of a first through hole is arranged adjacent to the first gap along the axial direction of the motor, so that the coolant located in the first gap can flow directly to the first through hole.

[0012] On the basis that each first stator core includes a first through hole and another first through hole, if other methods are used to transport coolant to a first through hole and another first through hole: one possible method is that the motor does not include a second stator core, and an additional radial flow channel is opened in each first stator core, and the radial flow channel is used to connect a first through hole and another first through hole. After the coolant flows from the inner circumference of the motor housing into the other first through hole, it can continue to flow to the first through hole. In this case, a first through hole and another first through hole actually form a series of flow channels, the cooling effects will affect each other, and blockage somewhere will affect the flow of coolant in the entire first stator core. In addition, this method increases the volume of the flow channel opened in the first stator core, which will have a negative impact on the electromagnetic performance of the first stator core.

[0013] Another possible way is that a second stator core of the motor is not located between a first stator core and another first stator core, but is located on the side of a first stator core away from another first stator core along the axial direction of the motor, and one path of coolant needs to flow through another first through hole and a first through hole of a first stator core before it can flow to a first through hole of another first stator core, while another path of coolant can flow directly to another first through hole of another first stator core. That is, another first through hole of a first stator core, a first through hole of a first stator core, and a first through hole of another first stator core form a series flow channel, and as the coolant flows in the series flow channel, the temperature continues to rise, so that the cooling effect of the coolant in a first through hole in another first stator core is poorer than the cooling effect of another first through hole of another first stator core, and the other first stator core may have the problem of uneven cooling effect.

[0014] Compared with the above two methods, a second stator core in the embodiment of the present application is located between a first stator core and another first stator core, and a first through hole and another first through hole of each first stator core share a first gap of a second stator core, that is, in the two first stator cores, the flow channels formed by a first through hole and another first through hole are connected in parallel and will not interfere with each other. The flow channels formed by a first through hole and another first through hole both start from the first gap of a second stator core, and the coolant can flow directly to the first through holes at different positions in different first stator cores through the first gap, thereby realizing independent cooling of each first stator core, which is beneficial to reducing the loss of the coolant in the transmission path, and can also reduce the difference in cooling effects at different positions in the same first stator core, thereby improving the cooling efficiency of the motor as a whole.

[0015] In one embodiment, the outer diameter of at least a portion of the outer circumference of a second stator core along the radial direction of the motor is greater than the maximum distance between each winding slot and the axis of the motor, and the outer diameter of at least a portion of the outer circumference of a second stator core along the radial direction of the motor is less than the maximum distance between a first through hole and the axis of the motor.

[0016] In an embodiment of the present application, a first through hole is closer to the axis of the motor than another first through hole in the radial direction of the motor, and the maximum distance between a first through hole and the axis of the motor is greater than the maximum distance between each winding slot and the axis of the motor, indicating that the projection of a first through hole along the circumference of the motor does not overlap with each winding slot. In order to enable the first gap to deliver coolant to a first through hole, since a first through hole is not located between two winding slots, the outer diameter of at least part of the outer circumference of the second stator core can be adjusted to be less than the maximum distance between a first through hole and the axis of the motor. In this case, the positional relationship of the second stator core and the inner circumference of the motor housing is caused by the size of the outer diameter of the second stator core. In one embodiment, all outer circumferences of the second stator core and the inner circumference of the motor housing are spaced apart in the radial direction of the motor.

[0017] In the embodiment of the present application, the outer diameter of the second stator core cannot be too small, otherwise it may have a negative impact on the winding slot to accommodate the wire. Therefore, the outer diameter of the second stator core is larger than the maximum distance between each winding slot and the axis of the motor, ensuring that each winding slot of the first stator core and the second stator core can be aligned along the axial direction of the motor.

[0018] In one embodiment, a first through hole is arranged between two adjacent winding slots along the circumference of the motor, and a maximum distance between a first through hole and the axis of the motor along the radial direction of the motor is less than or equal to a maximum distance between each winding slot and the axis of the motor.

[0019] At least a portion of the outer circumference of a second stator core includes a first groove, and the first groove penetrates the second stator core along the axial direction of the motor. An opening of the first groove along the radial direction of the motor faces the inner circumference of a motor housing, and at least a portion of the projection of a first through hole along the axial direction of the motor is located within the projection of the first groove.

[0020] In an embodiment of the present application, taking a first stator core as an example, the position of a first through hole in a first stator core may also be changed according to heat dissipation requirements. For example, a first through hole is located between two adjacent winding slots along the circumference of the motor. Structurally, the maximum distance between a first through hole and the axis of the motor is less than or equal to the maximum distance between each winding slot and the axis of the motor. Since the distance between a first through hole and the winding slot is shortened, the cooling effect on multiple wires in the winding slot can be further enhanced.

[0021] In an embodiment of the present application, the structure or outer diameter of the outer circumference of a second stator core used to form the first gap needs to be adjusted accordingly according to the position of a first through hole. When a first through hole is located between two adjacent winding slots, since the outer diameter of a second stator core cannot be less than the maximum spacing between the winding slot and the axis of the motor, part of the outer circumference of a second stator core can be recessed along the radial direction of the motor toward the axis of the motor to form a first groove, so that the first groove is used to form a first gap with the two first stator cores and the inner circumference of the motor housing. Among them, the first groove runs through a second stator core along the axial direction of the motor, which is conducive to the second stator core playing a diversion role and reducing the flow resistance of the coolant. An opening of the first groove is radially toward the inner circumference of the motor housing, and the bottom of the first groove and a first through hole are both located between the same two winding slots, so that the projection of the first groove along the axial direction of the motor can cover at least part of the projection of a first through hole along the axial direction of the motor, so as to achieve the connection between the first groove and a first through hole.

[0022] In one embodiment, a minimum width of a first groove along the circumferential direction of the motor is greater than an inner diameter of each first through hole.

[0023] In an embodiment of the present application, the first gap formed by the first groove is used to guide the coolant to a first through hole and another first through hole of each first stator core. The minimum width of the first groove along the circumference of the motor is greater than the inner diameter of each first through hole, so that the projection of the first groove along the axial direction of the motor can cover one first through hole and another first through hole, which is beneficial to increase the volume of coolant that the first groove can receive and reduce the resistance of the coolant flowing from the first groove to one first through hole and another first through hole.

[0024] In one embodiment, a width of an opening of a first groove along the circumferential direction of the motor is greater than a width of a groove bottom of the first groove.

[0025] In an embodiment of the present application, the opening and the bottom of the first groove are respectively close to the inner circumferential surface of the motor housing and the axis of the motor, and the coolant flows from the opening of the first groove to the bottom of the groove. The circumferential width of the opening of the first groove is greater than the circumferential width of the bottom of the first groove, which is beneficial to reducing the flow resistance of the coolant in the first groove.

[0026] In one embodiment, a maximum distance between a first groove and the axis of the motor in the radial direction of the motor is less than or equal to a maximum distance between another first through hole and the axis of the motor.

[0027] The embodiment of the present application is conducive to increasing the volume of the first gap, improving the fluidity of the first gap, and can also avoid reducing the cooling efficiency of the winding due to excessive coolant overflowing to the outer peripheral surface of each first stator core. In one embodiment, another first through hole is arranged at intervals with the outer peripheral surface of each first stator core along the radial direction of the motor. In the embodiment of the present application, another first through hole receives the coolant through the first gap of a second stator core, so the spacing between another first through hole and the outer peripheral surface of each first stator core does not cause the coolant to be unable to flow into the other first through hole.

[0028] In one embodiment, at least a portion of the outer circumferential surface of a second stator core includes a plurality of first grooves, the plurality of first grooves are arranged in sequence along the circumference of the motor, each first groove is used to form a first gap, and the ratio of the number of first grooves of a second stator core to the number of first through holes of each first stator core is less than or equal to 1 / 2.

[0029] In an embodiment of the present application, a second stator core includes a plurality of first grooves, the number of grooves of a second stator core is less than or equal to half the number of first through holes of each first stator core, and each first groove is used to connect at least two first through holes of each first stator core, which is conducive to improving the efficiency of each first groove in distributing coolant. The plurality of first grooves are arranged in sequence along the circumference of the motor, and each first groove is distributed at a different position of a second stator core, which can transport the coolant to the first through holes located at different positions in each first stator core, and can expand the heat dissipation area of ​​the coolant in the stator core.

[0030] In one embodiment, an inner circumferential surface of a motor housing includes a second groove, wherein the second groove is recessed away from a second stator core in the radial direction of the motor, and the second groove extends in the circumferential direction of the motor.

[0031] In the embodiment of the present application, part of the inner circumference of the motor housing is recessed away from a second stator core in the radial direction of the motor to form a second groove, and the second groove is used to participate in forming the first gap. The second groove extends along the circumference of the motor, so that the coolant can flow along the circumference of the motor, and the communication between multiple first grooves in a second stator core is achieved, which is conducive to reducing the flow resistance of the coolant and improving the heat dissipation efficiency.

[0032] In one embodiment, the inner circumference of a motor housing includes a liquid inlet, and the distance between the center of the liquid inlet and a second stator core along the axial direction of the motor is smaller than the distance between the center of the liquid inlet and two first stator cores.

[0033] In an embodiment of the present application, the inner circumferential surface of the motor housing transports coolant to a second stator core through a liquid inlet. Among them, a second stator core is located between two first stator cores along the axial direction of the motor, and the axial spacing between the center of the liquid inlet and a second stator core is smaller than the spacing between the center of the liquid inlet and each first stator core, so that the coolant flowing out of the liquid inlet can smoothly flow to a second stator core. In one embodiment, the liquid inlet is aligned with the first groove along the radial direction of the motor. The embodiment of the present application enables the coolant to flow directly from the liquid inlet into the first groove, shortening the transmission path of the coolant between the liquid inlet and the first groove, which is beneficial to reducing the energy loss of the coolant. In one embodiment, the liquid inlet is located in the second groove.

[0034] In one embodiment, the thickness of the second stator core along the axial direction of the motor is smaller than the thickness of any one of the two first stator cores.

[0035] In an embodiment of the present application, a second stator core mainly serves to distribute the coolant. The axial thickness of a second stator core is less than the axial thickness of each first stator core, so that the coolant can flow from a second stator core to each first stator core more quickly. At least part of the outer circumference of a second stator core needs to be spaced from the inner circumference of the motor housing, so at least part of the outer circumference of a second stator core needs to be reduced in diameter or a first groove is provided. In an embodiment of the present application, the axial thickness of a second stator core is relatively small, which is equivalent to a smaller adjustment of the multiple stator cores as a whole, and can reduce the impact on the electromagnetic performance of the multiple stator cores as a whole.

[0036] In an embodiment of the present application, the axial thickness of each first stator core is relatively large, and the multiple first through holes of each first stator core can receive coolant through the first gap. The coolant can cool each first stator core with a relatively large axial thickness, which is beneficial to expanding the contact area between the coolant and the multiple stator cores.

[0037] In one embodiment, the plurality of stator cores further include another second stator core and a third stator core, and the other second stator core is arranged between a first stator core and a third stator core along the axial direction of the motor.

[0038] A third stator core includes a plurality of second through holes, which penetrate the third stator core along the axial direction of the motor, and the maximum distance between the plurality of second through holes and the axis of the motor along the radial direction of the motor is smaller than the maximum distance between another first through hole and the axis of the motor.

[0039] At least part of the outer circumference of another second stator core forms a second gap with a first stator core, a third stator core, and a motor housing. Along the axial direction of the motor, another opening of a first through hole, another opening of another first through hole, an opening of a second through hole, and an opening of another second through hole are exposed to a second gap. Along the radial direction of the motor, the maximum spacing between a second through hole and the axis of the motor is smaller than the minimum spacing between another second through hole and the axis of the motor.

[0040] In an embodiment of the present application, since the multiple first through holes of a first stator core and the multiple second through holes of a third stator core are not completely aligned, if a first stator core and a third stator core are directly arranged adjacent to each other along the axial direction of the motor, the coolant in the other first through hole will not be able to flow to the third stator core. Therefore, the embodiment of the present application forms a second gap with the help of another second stator core, and the projection of the second gap along the axial direction of the motor covers the multiple first through holes of a first stator core and the multiple second through holes of the third stator core, so that the second through hole can receive the coolant delivered from a first stator core.

[0041] In the embodiment of the present application, in addition to realizing the circulation of coolant between a first stator core and a third stator core, another second stator core can also be used to alleviate the blockage problem and realize the reasonable distribution of the coolant flow of different stator cores.

[0042] If one of the second through holes and the other second through holes is blocked, since the second through hole and the other second through hole form two parallel flow channels, the parallel flow channels do not affect each other, making it difficult for the other of the second through holes and the other second through holes to play a role in preventing blockage. The other second stator core of the embodiment of the present application actually provides an occasion for connecting different parallel flow channels in a first stator core and a third stator core in series. Taking the blockage of a second through hole as an example, since the other second stator core is far away from the liquid inlet relative to the one second stator core along the axial direction of the motor, the power of the coolant in the other second stator core will be less than the power of the coolant in the one second stator core, so that the coolant in the one second through hole can flow back to the second gap of the other second stator core and continue to flow into the other second through hole. The same applies to the blockage of another second through hole.

[0043] In addition, even if there is no blockage, when the flow rate of a first through hole in a first stator core is greater than the flow rate of another first through hole, the flow rate of the coolant can be redistributed through another second stator core, that is, part of the coolant in a first through hole flows into a second through hole through the second gap of another second stator core, and another part of the coolant in a first through hole flows into another second through hole through the second gap of another second stator core, thereby avoiding the problem of insufficient local coolant in the third stator core. The same applies when the flow rate of another first through hole in a first stator core is greater than the flow rate of a first through hole.

[0044] In one embodiment, the thickness of the other second stator core along the axial direction of the motor is smaller than the thickness of any one of the first stator core and the third stator core.

[0045] In the embodiment of the present application, the other second stator core mainly serves to distribute the coolant. The axial thickness of the other second stator core is less than the thickness of any one of the first stator core and the third stator core, so that the coolant can flow from the other second stator core to the third stator core more quickly. In addition, the influence on the electromagnetic performance of the plurality of stator cores as a whole can be reduced.

[0046] In the embodiment of the present application, the axial thickness of the third stator core is relatively large, and the multiple second through holes of the third stator core can receive coolant through the second gap. The coolant can cool the third stator core with a relatively large axial thickness, which is beneficial to expanding the contact area between the coolant and the multiple stator cores.

[0047] In one embodiment, the distance between a third stator core and one end of the plurality of wires is smaller than the distance between a first stator core and one end of the plurality of wires. In an embodiment of the present application, along the axial direction of the motor, a third stator core, another second stator core and a first stator core are arranged in sequence. Among them, the maximum radial distance between the plurality of second through holes and the axis of the motor is smaller than the maximum radial distance between another first through hole and the axis of the motor, that is, the plurality of second through holes are closer to the plurality of wires in the winding slots than the other first through hole. The third stator core is closer to one end of the plurality of wires than the first stator core, which is conducive to improving the cooling efficiency of the coolant in the second through hole on the ends of the wires.

[0048] In one embodiment, the multiple stator cores further include a fourth stator core, a third stator core is located between another second stator core and a fourth stator core along the axial direction of the motor, and one end of the multiple wires is exposed in each winding slot of a fourth stator core.

[0049] A fourth stator core includes a plurality of third through holes, the plurality of third through holes penetrate the fourth stator core, the extension direction of the plurality of third through holes intersects with the axis of the motor, one opening of each third through hole is arranged adjacent to another opening of another second through hole in a third stator core along the axial direction of the motor, and the distance between each third through hole and the axis of the motor along the radial direction of the motor decreases from one opening of each third through hole toward another opening of each third through hole.

[0050] In an embodiment of the present application, the fourth stator core, the third stator core and another second stator core are arranged in sequence along the axial direction of the motor. Among them, the fourth stator core is closer to one end of the multiple wires than the third stator core along the axial direction of the motor, and one end of the multiple wires is exposed in each winding slot of the fourth stator core. The fourth stator core includes a plurality of third through holes, one third through hole is connected to another second through hole of the third stator core, and each third through hole can receive the coolant transmitted by the third stator core. Different from the extension direction of the first through hole and the second through hole, the extension direction of the third through hole of the fourth stator core intersects with the axis of the motor, and the distance between the third through hole and one end of the multiple wires along the radial direction of the motor gradually decreases, so that the coolant can be sprayed from the third through hole to the outside of one end of the multiple wires, so as to cool the winding end and improve the utilization rate of the coolant.

[0051] In one embodiment, a fourth stator core further includes a plurality of fourth through holes, and the plurality of fourth through holes penetrate a fourth stator core along the axial direction of the motor. The maximum distance between each fourth through hole and the axis of the motor along the radial direction of the motor is less than the minimum distance between each third through hole and the axis of the motor. An opening of each fourth through hole along the axial direction of the motor is arranged adjacent to a second through hole of a third stator core.

[0052] In the embodiment of the present application, the plurality of fourth through holes of the fourth stator core extend along the axial direction of the motor, each of the fourth through holes is connected to a second through hole of the third stator core, and the fourth through holes can receive coolant from the third stator core. In the radial direction of the motor, each fourth through hole is closer to the axis of the motor than each third through hole, and the fourth through holes cooperate with the third through holes to achieve three-dimensional cooling of the plurality of wires, and comprehensively improve the heat dissipation effect of the winding ends.

[0053] In a second aspect, an embodiment of the present application provides a power assembly, which includes a motor controller, a reducer and a motor as described in any embodiment of the first aspect, wherein the motor controller is used to provide electrical energy to the windings of the motor, and the motor is used to transmit power to the reducer.

[0054] In the embodiment of the present application, the motor as described in the first aspect is used in the powertrain, which can improve the cooling efficiency of the winding and the stator core, so that the safety performance of the motor's working efficiency is enhanced, which is beneficial to improving the power density of the powertrain and reducing the safety risks of the powertrain.

[0055] In a third aspect, an embodiment of the present application provides a vehicle, comprising a frame, a battery pack and a powertrain as described in the second aspect, wherein the frame is used to fix the battery pack and the powertrain, the battery pack is used to supply power to the motor through a motor controller, and the powertrain is used to drive the wheels of the vehicle through the motor.

[0056] In the embodiment of the present application, adopting the power assembly as described in the second aspect in the vehicle is beneficial to improving the heat dissipation effect of the power assembly and ensuring smooth and safe driving of the vehicle. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings required for use in the embodiments of the present application will be described below.

[0058] Figure 1 is a schematic structural diagram of a vehicle provided in an embodiment of the present application;

[0059] Figure 2 is a schematic diagram of the structure of a powertrain provided in an embodiment of the present application;

[0060] Figure 3 is a schematic diagram of a partial structure of a motor provided in an embodiment of the present application;

[0061] Figure 4 is a partial cross-sectional view of a motor provided in an embodiment of the present application;

[0062] Figure 5 is a partial cross-sectional view of a motor provided in an embodiment of the present application;

[0063] Figure 6 yes Figure 5 A partial enlarged view of the M portion of the motor shown;

[0064] Figure 7 It is a schematic diagram of the local structure of a motor in the prior art;

[0065] Figure 8 is a schematic diagram of a partial structure of a motor provided in an embodiment of the present application;

[0066] Fig. 9 is a schematic structural diagram of a second stator core provided in an embodiment of the present application;

[0067] Fig.10 is a cross-sectional view of a motor housing provided in an embodiment of the present application;

[0068] Fig.11 is a partial exploded diagram of a motor provided in an embodiment of the present application;

[0069] Fig.12 is a partial cross-sectional view of a motor provided in an embodiment of the present application;

[0070] Fig.13 is a schematic diagram of a partial structure of a motor provided in an embodiment of the present application;

[0071] Fig.14 is a partial cross-sectional view of a motor provided in an embodiment of the present application;

[0072] Fig.15 yes Fig.14 A partial enlarged view of the N part of the motor shown;

[0073] Fig.16 is a partial exploded diagram of a motor provided in an embodiment of the present application;

[0074] Fig.17 It is a partial cross-sectional view of the motor provided in an embodiment of the present application. DETAILED DESCRIPTION

[0075] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0076] At present, the cooling efficiency of the winding of the motor is low. To solve the above problem, an embodiment of the present application provides a motor, which includes a motor housing and a plurality of stator cores. The motor housing is used to accommodate the plurality of stator cores. The plurality of winding slots of each stator core are arranged in sequence along the circumference of the motor, and each winding slot is used to accommodate a plurality of wires of the winding.

[0077] The plurality of stator cores include two first stator cores and one second stator core. The two first stator cores are fixed to the inner circumference of a motor housing. Each first stator core includes a plurality of first through holes, and the plurality of first through holes penetrate each first stator core along the axial direction of the motor, and the plurality of first through holes of each first stator core are spaced from the plurality of winding slots of each first stator core. A second stator core is arranged between the two first stator cores along the axial direction of the motor.

[0078] At least part of the outer circumference of a second stator core is spaced apart from the inner circumference of the motor housing along the radial direction of the motor, and at least part of the outer circumference of a second stator core forms a first gap with the two first stator cores and the motor housing. A first through hole and another first through hole of each first stator core receive the coolant output from the inner circumference of the motor housing through the first gap. An opening of a first through hole and an opening of another first through hole in each first stator core are exposed to the first gap along the axial direction of the motor. The maximum spacing between a first through hole and the axis of the motor along the radial direction of the motor is smaller than the minimum spacing between another first through hole and the axis of the motor.

[0079] The embodiment of the present application enhances the cooling effect of the stator core and the winding by cooperating through holes and grooves in different stator cores. The motor provided in the embodiment of the present application is applied to a powertrain, wherein the powertrain including the flat wire motor of the present application is applied to a vehicle.

[0080] See also Figure 1 , Figure 1 A schematic diagram of the structure of a vehicle 1 provided in an embodiment of the present application. In the embodiment of the present application, vehicle 1 refers to a wheeled device driven or towed by a power device. In the embodiment of the present application, vehicle 1 includes a frame 20, a battery pack 30 and a powertrain 10. Among them, the frame 20 is the structural skeleton of the vehicle 1, and the frame 20 is used to install the battery pack 30 and the powertrain 10, and can bear the internal and external environmental loads of the vehicle 1. The battery pack 30 is used to supply power to the powertrain 10, and the battery pack 30 can also be called a power battery. The powertrain 10 is the power source of the vehicle 1, and the powertrain 10 is used to drive the wheels 40 of the vehicle 1.

[0081] See also Figure 2 , Figure 2 This is a schematic diagram of the structure of the powertrain 10 provided in the embodiment of the present application. In the embodiment of the present application, the powertrain 10 includes a motor 11, a motor controller 12, and a reducer 13. The motor controller 12 is used to convert the direct current provided by the battery pack 30 into alternating current, and transmit the alternating current to the motor 11. The motor 11 is connected to the reducer 13 in a transmission manner to drive the wheels 40 to rotate.

[0082] Among them, the motor is an electromagnetic device that realizes the conversion or transmission of electric energy according to the law of electromagnetic induction, and can generate driving torque. Specifically, in one embodiment, the motor includes a stator core, a motor rotor, a motor shaft and a winding, and the multiple wires of the winding generate alternating magnetic flux after the alternating current transmitted by the motor controller is passed through. The alternating magnetic flux generated by the winding interacts with the permanent magnetic flux generated by the motor rotor, so that the motor rotor rotates relative to the stator core, the motor rotor is fixedly connected to the motor shaft, so that the motor shaft rotates with the motor rotor, and the stator core is rotationally connected to the motor shaft, so that the motor shaft can rotate relative to the stator core, converting electric energy into mechanical energy, and the output end of the motor shaft is used to transmit mechanical energy.

[0083] During the operation of the motor, the energy lost in the stator core and windings will gradually turn into heat, causing the winding temperature to continue to rise. If the cooling effect of the winding is not good, it will not only directly damage the service life of the winding and reduce the working efficiency of the motor, but also cause electrical failures and safety accidents in serious cases.

[0084] The embodiments of the present application improve the flow channel structure of the stator core to improve the cooling efficiency of the stator core and the winding, thereby avoiding negative impacts on the motor and improving the safety performance of the vehicle.

[0085] See also Figures 3 to 6 , Figure 3 A schematic diagram of a partial structure of the motor 11 provided in an embodiment of the present application, Figure 4 A partial cross-sectional view of the motor 11 provided in an embodiment of the present application, Figure 5 A partial cross-sectional view of the motor 11 provided in an embodiment of the present application, Figure 6 for Figure 5 A partial enlarged view of the M portion of the motor 11 is shown.

[0086] The motor 11 includes a motor housing 120 and a plurality of stator cores 110. The motor housing 120 is used to accommodate the plurality of stator cores 110. The plurality of winding slots 1100 of each stator core 110 are arranged in sequence along the circumferential direction C of the motor 11. Each winding slot 1100 is used to accommodate a plurality of wires 131. The plurality of stator cores 110 include two first stator cores 111 and a second stator core 112. A second stator core 112 is arranged between the two first stator cores 111 along the axial direction of the motor 11. Each first stator core 111 includes a plurality of first through holes 1111. The plurality of first through holes 1111 penetrates each first stator core 111 along the axial direction of the motor 11. The plurality of first through holes 1111 of each first stator core 111 are spaced from the plurality of winding slots 1100 of each first stator core 111.

[0087] At least a portion of the outer circumference of a second stator core 112 is spaced apart from an inner circumference of a motor housing 120 along a radial direction R of the motor 11. At least a portion of the outer circumference of a second stator core 112 forms a first gap 140 with two first stator cores 111 and a motor housing 120. A first through hole 1111 and another first through hole 1111 of each first stator core 111 receive the coolant output from the inner circumference of a motor housing 120 through a first gap 140. An opening of a first through hole 1111 and an opening of another first through hole 1111 in each first stator core 111 are exposed to a first gap 140 along the axial direction of the motor 11. A maximum spacing between a first through hole 1111 and an axis O of the motor 11 along a radial direction R of the motor 11 is smaller than a minimum spacing between another first through hole 1111 and an axis O of the motor 11.

[0088] In the embodiment of the present application, for ease of description, the two first stator cores 111 are respectively recorded as the first stator core 111a and the first stator core 111b, the second stator core 112 is recorded as the second stator core 112a, the first through hole 1111 of each first stator core 111 is recorded as the first through hole 1111a, and the other first through hole 1111 of each first stator core 111 is recorded as the first through hole 1111b. The axial direction of the motor 11 is the extension direction of the axis O of the motor 11, and the axial direction of the motor 11 is also recorded as the axial direction O of the motor 11.

[0089] When the motor 11 is in operation, the multiple wires 131 of the winding 130 are supplied with alternating current, which causes resistance loss. The alternating magnetic flux generated after the wires 131 are energized will also cause hysteresis loss and eddy current loss in the multiple stator cores 110, causing the heat generated by the stator core 110 and the winding 130 to continue to increase.

[0090] In the embodiment of the present application, each first stator core 111 includes a first through hole 1111a and a first through hole 1111b. The maximum spacing between the first through hole 1111a and the axis O of the motor 11 along the radial direction R of the motor 11 refers to the maximum length of the connection line between the axis O of the motor 11 and the hole wall of the first through hole 1111a along the radial direction R of the motor 11. The minimum spacing between the first through hole 1111b and the axis O of the motor 11 along the radial direction R of the motor 11 refers to the minimum length of the connection line between the axis O of the motor 11 and the hole wall of the first through hole 1111b along the radial direction R of the motor 11. The maximum spacing between the first through hole 1111a and the axis O of the motor 11 along the radial direction R of the motor 11 is less than the minimum spacing between the first through hole 1111b and the axis O of the motor 11, that is, the axial projections of the first through hole 1111a and the first through hole 1111b do not overlap. By supplying cooling liquid to the first through hole 1111 a and the first through hole 1111 b , it is possible to take into account the heat dissipation effect on the stator core 110 and the winding slot 1100 , thereby realizing multi-level cooling in the motor 11 .

[0091] In the embodiment of the present application, the first through hole 1111a and the first through hole 1111b are spaced apart, so that the first through hole 1111a and the first through hole 1111b form two parallel flow channels in a single first stator core 111. In order to deliver the coolant to the first through hole 1111a and the first through hole 1111b of each first stator core 111, the embodiment of the present application uses at least part of the outer circumference of the second stator core 112a and the inner circumference of the two first stator cores 111 and the motor housing 120 to form a first gap 140, and one opening of the first through hole 1111a and the first through hole 1111b of each first stator core 111 is exposed to the first gap 140, so that the coolant delivered by the inner circumference of the motor housing 120 can flow to the first through hole 1111a and the first through hole 1111b of the two first stator cores 111 through the first gap 140, which is conducive to reducing the loss of the coolant in the transmission path of each first stator core 111. In one embodiment, the coolant is any one of ethylene glycol cooling oil, synthetic oil and mineral oil.

[0092] Among them, taking the first through hole 1111a as an example, an opening of the first through hole 1111a is exposed to the first gap 140, which means that an opening of the first through hole 1111a is arranged adjacent to the first gap 140 along the axial direction O of the motor 11, so that the coolant located in the first gap 140 can flow directly to the first through hole 1111a.

[0093] On the basis that each first stator core 111 includes a first through hole 1111a and a first through hole 1111b, if other methods are used to transport coolant to the first through hole 1111a and the first through hole 1111b: one possible method is that the motor 11 does not include the second stator core 112a, and an additional radial flow channel is opened in each first stator core 111, and the first through hole 1111a and the first through hole 1111b are connected by the radial flow channel. After the coolant flows into the first through hole 1111b from the inner circumference of the motor housing 120, it can continue to flow to the first through hole 1111a. In this case, the first through hole 1111a and the first through hole 1111b actually form a series of flow channels, the cooling effects will affect each other, and blockage somewhere will affect the flow of the coolant in the entire first stator core 111. In addition, this method increases the volume of the flow channel opened in the first stator core 111, which will have a negative impact on the electromagnetic performance of the first stator core 111.

[0094] See also Figure 7 , Figure 7 It is a schematic diagram of the local structure of the motor in the prior art. Another possible way is that the second stator core 112a of the motor 11 is not located between the first stator core 111a and the first stator core 111b, but is located on the side of the first stator core 111a away from the first stator core 111b along the axial direction O of the motor 11. One path of coolant needs to first flow through the first through hole 1111b of the first stator core 111a and the first through hole 1111a before it can flow to the first through hole 1111a of the first stator core 111b, while the other path of coolant can flow directly to the first through hole 1111b of the first stator core 111b. That is, the first through hole 1111b of the first stator core 111a, the first through hole 1111a of the first stator core 111a, and the first through hole 1111a of the first stator core 111b form a series flow channel. As the coolant flows in the series flow channel, the temperature continues to rise, so that the cooling effect of the coolant in the first through hole 1111a in the first stator core 111b is poorer than the cooling effect of the first through hole 1111b of the first stator core 111b, and the first stator core 111b may have a problem of uneven cooling effect.

[0095] Compared with the above two methods, the second stator core 112a in the embodiment of the present application is located between the first stator core 111a and the first stator core 111b, and the first through hole 1111a and the first through hole 1111b of each first stator core 111 share the first gap 140 of the second stator core 112a, that is, in the two first stator cores 111, the flow channels formed by each first through hole 1111a and each first through hole 1111b are connected in parallel and will not interfere with each other. The flow channel formed by each first through hole 1111a and each first through hole 1111b starts from the first gap 140 of the second stator core 112a. The coolant can flow directly to the first through holes 1111 at different positions in different first stator cores 111 through the first gap 140, thereby realizing independent cooling of each first stator core 111, which is beneficial to reducing the loss of coolant in the transmission path, and can also narrow the difference in cooling effects at different positions in the same first stator core 111, thereby improving the overall cooling efficiency of the motor 11.

[0096] It should be noted that Figure 7 The different distances between the first through hole 1111a, the first through hole 1111b and the axis O of the motor 11 are only schematically shown, which does not represent the specific position of the axis O of the motor 11.

[0097] Please continue reading Figure 4 and Figure 5 In one embodiment, along the circumferential direction C of the motor 11, the first through hole 1111a of each first stator core 111 is arranged between two adjacent winding slots 1100. Along the radial direction R of the motor 11, the maximum distance between the first through hole 1111a of each first stator core 111 and the axis O of the motor 11 is less than or equal to the maximum distance between each winding slot 1100 and the axis O of the motor 11.

[0098] At least part of the outer circumference of the second stator core 112a includes a first groove 1121, and the first groove 1121 penetrates the second stator core 112a along the axial direction O of the motor 11. An opening of the first groove 1121 along the radial direction R of the motor 11 faces the inner circumference of the motor housing 120, and at least part of the projection of the first through hole 1111a along the axial direction O of the motor 11 is located within the projection of the first groove 1121.

[0099] In the embodiment of the present application, the maximum distance between each winding slot 1100 and the axis O of the motor 11 refers to the maximum length of the connecting line between the axis O of the motor 11 and the slot wall of each winding slot 1100 along the radial direction R of the motor 11.

[0100] In the embodiment of the present application, taking the first stator core 111a as an example, the position of the first through hole 1111a in the first stator core 111a can be changed according to the heat dissipation requirements. For example, the first through hole 1111a is located between two adjacent winding slots 1100 along the circumferential direction C of the motor 11. Structurally, the maximum distance between the first through hole 1111a and the axis O of the motor 11 is less than or equal to the maximum distance between each winding slot 1100 and the axis O of the motor 11. Since the distance between the first through hole 1111a and the winding slot 1100 is shortened, the cooling effect on the multiple wires 131 in the winding slot 1100 can be further enhanced.

[0101] In the embodiment of the present application, the structure or outer diameter of the outer circumference of the second stator core 112a used to form the first gap 140 needs to be adjusted accordingly according to the position of the first through hole 1111a. When the first through hole 1111a is located between two adjacent winding slots 1100, since the outer diameter of the second stator core 112a cannot be less than the maximum distance between the winding slot 1100 and the axis O of the motor 11, part of the outer circumference of the second stator core 112a can be recessed along the radial direction R of the motor 11 toward the axis O of the motor 11 to form a first groove 1121, so that the first groove 1121 is used to form the first gap 140 with the two first stator cores 111 and the inner circumference of the motor housing 120. Among them, the first groove 1121 penetrates the second stator core 112a along the axial direction O of the motor 11, which is conducive to the second stator core 112a playing a diversion role and reducing the flow resistance of the coolant. An opening of the first groove 1121 faces the inner circumferential surface of the motor housing 120 along the radial direction R of the motor 11, and the bottom of the first groove 1121 and the first through hole 1111a are both located between the same two winding slots 1100, so that the axial projection of the first groove 1121 can cover at least part of the axial projection of the first through hole 1111a, thereby realizing the connection between the first groove 1121 and the first through hole 1111a.

[0102] It should be noted that the projections of the through hole and the groove refer to the projections of the areas enclosed by the hole wall of the through hole and the inner wall of the groove, respectively.

[0103] See also Figure 8 , Figure 8 A schematic diagram of a partial structure of the motor 11 provided in an embodiment of the present application. In another embodiment, the outer diameter of at least a portion of the outer circumference of the second stator core 112a along the radial direction R of the motor 11 is smaller than the maximum distance between the first through hole 1111a of each first stator core 111 and the axis O of the motor 11. Accordingly, the outer diameter of at least a portion of the outer circumference of the second stator core 112a along the radial direction R of the motor 11 may also be greater than the maximum distance between each winding slot 1100 and the axis O of the motor 11.

[0104] In the embodiment of the present application, taking the first stator core 111a as an example, along the radial direction R of the motor 11, the first through hole 1111a is closer to the axis O of the motor 11 than the first through hole 1111b, and the maximum distance between the first through hole 1111a and the axis O of the motor 11 is greater than the maximum distance between each winding slot 1100 and the axis O of the motor 11, indicating that the projection of the first through hole 1111a along the circumferential direction C of the motor 11 does not overlap with each winding slot 1100. In order to enable the first gap 140 to transport the coolant to the first through hole 1111a, since the first through hole 1111a is not located between the two winding slots 1100, the outer diameter of at least part of the outer circumference of the second stator core 112a can be adjusted to be smaller than the maximum distance between the first through hole 1111a and the axis O of the motor 11. In this case, the positional relationship of the second stator core 112a and the inner circumference of the motor housing is caused by the outer diameter of the second stator core 112a. In one embodiment, all outer circumferential surfaces of the second stator core 112 a and the inner circumferential surface of the motor housing are arranged at intervals along the radial direction R of the motor 11 .

[0105] In the embodiment of the present application, the outer diameter of the second stator core 112a cannot be too small, otherwise it may have a negative impact on the winding slot 1100 to accommodate the wire. Therefore, the outer diameter of the second stator core 112a is larger than the maximum distance between each winding slot 1100 and the axis O of the motor 11, ensuring that each winding slot 1100 of the first stator core 111a and the second stator core 112a can be aligned along the axial direction O of the motor 11.

[0106] Please continue reading Figure 5 and Figure 6 In one embodiment, the minimum width of the first groove 1121 along the circumferential direction C of the motor 11 is greater than the inner diameter of each first through hole 1111 .

[0107] In the embodiment of the present application, taking the first through hole 1111a and the first through hole 1111b as an example, the first gap 140 formed by the first groove 1121 is used to guide the coolant to the first through hole 1111a and the first through hole 1111b of each first stator core 111, and the minimum width of the first groove 1121 along the circumferential direction C of the motor 11 is greater than the inner diameter of each first through hole 1111, so that the projection of the first groove 1121 along the axial direction O of the motor 11 can cover the first through hole 1111a and the first through hole 1111b, which is beneficial to increase the volume of coolant that the first groove 1121 can receive, and reduce the resistance of the coolant flowing from the first groove 1121 to the first through hole 1111a and the first through hole 1111b.

[0108] Please continue reading Figure 5 and Figure 6In one embodiment, the width of an opening of the first groove 1121 along the circumferential direction C of the motor 11 is greater than the width of the bottom of the first groove 1121 .

[0109] In the embodiment of the present application, the opening and the bottom of the first groove 1121 are respectively close to the inner circumferential surface of the motor housing 120 and the axis O of the motor 11. The coolant flows from the opening of the first groove 1121 to the bottom of the groove. The circumferential width of the opening of the first groove 1121 is greater than the circumferential width of the bottom of the first groove 1121, which is beneficial to reducing the flow resistance of the coolant in the first groove 1121.

[0110] Please continue reading Figure 6 In one embodiment, at least one groove wall of the first groove 1121 along the circumferential direction C of the motor 11 includes a first section 1121a and a second section 1121b connected to each other, the first section 1121a is used to form the opening of the first groove 1121, and the second section 1121b is used to form the groove bottom of the first groove 1121. The distance between the two ends of the first section 1121a along the radial direction R of the motor 11 is smaller than the length of the first section 1121a, and the angle between the extension direction of the first section 1121a and the radial direction R of the motor 11 is greater than the angle between the extension direction of the second section 1121b and the radial direction R of the motor 11.

[0111] In the embodiment of the present application, the coolant flows from the first section 1121a to the second section 1121b, and the inclination angle of the first section 1121a relative to the radial direction R of the motor 11 is greater than the inclination angle of the second section 1121b relative to the radial direction R of the motor 11, so that the first section 1121a can play a transition and buffering role for the coolant. The second section 1121b is used to form the bottom of the first groove 1121, and the angle between the second section 1121b and the radial direction R of the motor 11 is relatively small, which can more accurately guide the coolant to the first through hole 1111a.

[0112] Please continue reading Figure 5 In one embodiment, the maximum distance between the first groove 1121 and the axis O of the motor 11 along the radial direction R of the motor 11 is less than or equal to the maximum distance between the first through hole 1111b and the axis O of the motor 11.

[0113] In the embodiment of the present application, the maximum radial spacing between the first groove 1121 and the axis O of the motor 11 refers to the radial spacing between the opening of the first groove 1121 and the axis O of the motor 11. The embodiment of the present application is conducive to increasing the volume of the first gap 140, improving the fluidity of the first gap 140, and can also avoid reducing the cooling efficiency of the winding 130 due to excessive coolant overflowing to the outer circumference of each first stator core 111. In one embodiment, the first through hole 1111b is arranged at intervals with the outer circumference of each first stator core 111 along the radial direction R of the motor 11. In the embodiment of the present application, the first through hole 1111b receives the coolant through the first gap 140 of the second stator core 112a, so the spacing between the first through hole 1111b and the outer circumference of each first stator core 111 will not cause the coolant to be unable to flow into the first through hole 1111b. In one embodiment, the first through hole 1111b is connected to the outer circumference of each first stator core 111 along the radial direction R of the motor 11.

[0114] Please continue reading Figure 5 In one embodiment, at least part of the outer circumference of a second stator core 112 includes a plurality of first grooves 1121, and the plurality of first grooves 1121 are arranged in sequence along the circumferential direction C of the motor 11. Each first groove 1121 is used to form a first gap 140. The ratio of the number of first grooves 1121 of a second stator core 112 to the number of first through holes 1111 of each first stator core 111 is less than or equal to 1 / 2.

[0115] In the embodiment of the present application, the second stator core 112a includes a plurality of first grooves 1121, the number of grooves of the second stator core 112a is less than or equal to half the number of first through holes 1111 of each first stator core 111, and each first groove 1121 is used to connect at least two first through holes 1111 of each first stator core 111, which is conducive to improving the efficiency of distributing coolant in each first groove 1121. The plurality of first grooves 1121 are arranged in sequence along the circumferential direction C of the motor 11, and each first groove 1121 is distributed at a different position of the second stator core 112a, so that the coolant can be transported to the first through holes 1111 located at different positions in each first stator core 111, and the heat dissipation area of ​​the coolant in the stator core 110 can be expanded.

[0116] It should be noted that, in the embodiment of the present application, when the second stator core 112a includes a plurality of first grooves 1121, the first through hole 1111a and the first through hole 1111b of each first stator core 111 represent two types of first through holes 1111, that is, each first stator core 111 includes a plurality of first through holes 1111a and a plurality of first through holes 1111b, each first through hole 1111a is arranged in sequence along the circumferential direction C of the motor 11, and each first through hole 1111b is arranged in sequence along the circumferential direction C of the motor 11, and the maximum distance between each first through hole 1111a and the axis O of the motor 11 is less than the minimum distance between each first through hole 1111b and the axis O of the motor 11, and each first groove 1121 is used to correspond to a first through hole 1111a and a first through hole 1111b.

[0117] Please continue reading Figure 6 In one embodiment, when multiple stator cores 110 are fixed by welding, each first stator core 111 further includes a plurality of first welding grooves 1112, and the plurality of first welding grooves 1112 are arranged at intervals with the plurality of first through holes 1111b along the circumferential direction C of the motor 11. Each second stator core 112 further includes a plurality of second welding grooves 1122, and the plurality of second welding grooves 1122 are arranged at intervals with the plurality of first grooves 1121 along the circumferential direction C of the motor 11. The first welding grooves 1112 and the second welding grooves 1122 in the embodiment of the present application facilitate the fixation of the multiple stator cores 110 by welding operation. It is understandable that when the multiple stator cores 110 are fixed by other means, such as bonding or riveting, in this case, each first stator core 111 may not include the first welding groove 1112, and each second stator core 112 may not include the second welding groove 1122. Please refer to Fig. 9 , Fig. 9 The second stator core 112 is a schematic diagram of the structure of the second stator core 112 provided in the embodiment of the present application. The second stator core 112 may be as follows: Fig. 9 The structure shown is beneficial to increasing the volume of the first gap 140 and improving the fluidity.

[0118] Please refer to Figure 5 and Fig.10 , Fig.10 A cross-sectional view of the motor housing 120 provided in an embodiment of the present application. In one embodiment, the inner circumferential surface of the motor housing 120 includes a second groove 121, which is recessed away from the second stator core 112a along the radial direction R of the motor 11 and extends along the circumferential direction C of the motor 11.

[0119] In the embodiment of the present application, part of the inner circumferential surface of the motor housing 120 is recessed away from the second stator core 112a along the radial direction R of the motor 11 to form a second groove 121, and the second groove 121 is used to participate in forming the first gap 140. The second groove 121 extends along the circumferential direction C of the motor 11, so that the coolant can flow along the circumferential direction C of the motor 11, and the communication between the multiple first grooves 1121 in the second stator core 112a is achieved, which is conducive to reducing the flow resistance of the coolant and improving the heat dissipation efficiency.

[0120] Please continue reading Figure 5 and Fig.10 In one embodiment, the inner circumferential surface of a motor housing 120 includes a liquid inlet 122, and the distance between the center of the liquid inlet 122 and the second stator core 112a along the axial direction O of the motor 11 is smaller than the distance between the center of the liquid inlet 122 and the two first stator cores 111.

[0121] In an embodiment of the present application, the inner circumference of the motor housing 120 delivers coolant to the second stator core 112a through the liquid inlet 122. Among them, along the axial direction O of the motor 11, the second stator core 112a is located between the two first stator cores 111, and the axial spacing between the center of the liquid inlet 122 and the second stator core 112a is smaller than the spacing between the center of the liquid inlet 122 and each first stator core 111, so that the coolant flowing out of the liquid inlet 122 can smoothly flow to the second stator core 112a. In one embodiment, the liquid inlet 122 is aligned with the first groove 1121 along the radial direction R of the motor 11. The embodiment of the present application enables the coolant to flow directly from the liquid inlet 122 into the first groove 1121, shortening the transmission path of the coolant between the liquid inlet 122 and the first groove 1121, which is conducive to reducing the energy loss of the coolant. In one embodiment, the liquid inlet 122 is located in the second groove 121.

[0122] Please continue reading Figure 4 In one embodiment, the thickness of the second stator core 112 a along the axial direction O of the motor 11 is less than the thickness of any one of the two first stator cores 111 .

[0123] In the embodiment of the present application, the second stator core 112a mainly plays the role of distributing the coolant. The axial thickness of the second stator core 112a is less than the axial thickness of each first stator core 111, so that the coolant can flow from the second stator core 112a to each first stator core 111 more quickly. At least part of the outer circumference of the second stator core 112a needs to be spaced from the inner circumference of the motor housing 120. Therefore, at least part of the outer circumference of the second stator core 112a needs to be reduced in outer diameter or the first groove 1121 is provided. In the embodiment of the present application, the axial thickness of the second stator core 112a is relatively small, which is equivalent to a smaller adjustment of the plurality of stator cores 110 as a whole, and can reduce the impact on the electromagnetic performance of the plurality of stator cores 110 as a whole.

[0124] In the embodiment of the present application, the axial thickness of each first stator core 111 is relatively large, and the multiple first through holes 1111 of each first stator core 111 can receive coolant through the first gap 140. The coolant can cool each first stator core 111 with a relatively large axial thickness, which is beneficial to expanding the contact area between the coolant and the multiple stator cores 110.

[0125] See also Fig.11 and Fig.12 , Fig.11 This is a partial exploded view of the motor 11 provided in the embodiment of the present application. Fig.12 A partial cross-sectional view of the motor 11 provided in an embodiment of the present application. Fig.12 The black dashed line and the adjacent arrows in the figure represent the flow path and direction of the coolant, respectively.

[0126] In one embodiment, the plurality of stator cores 110 further include another second stator core 112 and a third stator core 113 , and along the axial direction O of the motor 11 , the other second stator core 112 is arranged between a first stator core 111 and a third stator core 113 .

[0127] Please refer to Figures 12 to 15 , Fig.13 A schematic diagram of a partial structure of the motor 11 provided in an embodiment of the present application, Fig.14 A partial cross-sectional view of the motor 11 provided in an embodiment of the present application, Fig.15 for Fig.14 The enlarged partial view of the N part of the motor 11 is shown. A third stator core 113 includes a plurality of second through holes 1131, and the plurality of second through holes 1131 penetrate the third stator core 113 along the axial direction O of the motor 11, and the maximum distance between the plurality of second through holes 1131 and the axis O of the motor 11 along the radial direction R of the motor 11 is smaller than the minimum distance between the first through hole 1111b and the axis O of the motor 11.

[0128] Please continue reading Figures 11 to 15 , at least part of the outer circumference of another second stator core 112 is arranged with an inner circumference of a motor housing in a radial direction R of the motor 11. At least part of the outer circumference of another second stator core 112 forms a second gap 150 with a first stator core 111, a third stator core 113, and a motor housing 120. A second through hole 1131 and another second through hole 1131 of a third stator core 113 receive the coolant outputted from the first stator core 111a through the second gap 150. Along the axial direction O of the motor 11, another opening of the first through hole 1111a, another opening of the first through hole 1111b, an opening of a second through hole 1131, and an opening of another second through hole 1131 are exposed to the second gap 150. Along the radial direction R of the motor 11, the maximum spacing between a second through hole 1131 and the axis O of the motor 11 is smaller than the minimum spacing between another second through hole 1131 and the axis O of the motor 11.

[0129] In the embodiment of the present application, for the convenience of description, another second stator core 112 is recorded as the second stator core 112b. Along the axial direction O of the motor 11, the third stator core 113, the second stator core 112b and the first stator core 111a are arranged in sequence. Among them, the maximum radial spacing between the plurality of second through holes 1131 and the axis O of the motor 11 is less than the maximum radial spacing between the first through hole 1111b and the axis O of the motor 11, that is, the plurality of second through holes 1131 are closer to the plurality of wires 131 in the winding slot 1100 than the first through hole 1111b. In one embodiment, the spacing between the third stator core 113 and one end of the plurality of wires 131 is less than the spacing between the first stator core 111a and one end of the plurality of wires 131. The third stator core 113 is closer to one end of the plurality of wires 131 than the first stator core 111a, which is conducive to improving the cooling efficiency of the coolant in the second through hole 1131 on the end of the wire 131.

[0130] In the embodiment of the present application, since the multiple first through holes 1111 of the first stator core 111a and the multiple second through holes 1131 of the third stator core 113 are not completely aligned, if the first stator core 111a and the third stator core 113 are directly arranged adjacent to each other along the axial direction O of the motor 11, the coolant in the first through hole 1111b will not be able to flow to the third stator core 113. Therefore, the embodiment of the present application forms a second gap 150 with the help of the second stator core 112b, and the projection of the second gap 150 along the axial direction O of the motor 11 covers the multiple first through holes 1111 of the first stator core 111a and the multiple second through holes 1131 of the third stator core 113, so that the second through hole 1131 can receive the coolant delivered from the first stator core 111a.

[0131] In the embodiment of the present application, for the convenience of description, one second through hole 1131 is recorded as a second through hole 1131a, and the other second through hole 1131 is recorded as a second through hole 1131b. Fig.12 As shown, the second stator core 112 b can not only realize the circulation of coolant between the first stator core 111 a and the third stator core 113 , but also be used to alleviate the blockage problem and realize the reasonable distribution of the coolant flow of different stator cores 110 .

[0132] Specifically, since the third stator core 113 is closer to one end of the wire 131 than the first stator core 111a, the second through hole 1131 of the third stator core 113 is more likely to be blocked than the first through hole 1111 of the first stator core 111a. If one of the second through hole 1131a and the second through hole 1131b is blocked, since the second through hole 1131a and the second through hole 1131b form two parallel flow channels, the parallel flow channels do not affect each other, making it difficult for the other of the second through hole 1131a and the second through hole 1131b to play a role in preventing blockage. The second stator core 112b of the embodiment of the present application actually provides an occasion for connecting different parallel flow channels in the first stator core 111a and the third stator core 113 in series. Taking the blockage of the second through hole 1131a as an example, since the second stator core 112b is far away from the liquid inlet 122 relative to the second stator core 112a along the axial direction O of the motor 11, the power of the coolant in the second stator core 112b will be less than the power in the second stator core 112a, so that the coolant in the second through hole 1131a can flow back to the second gap 150 of the second stator core 112b and continue to flow into the second through hole 1131b. The same is true for the blockage of the second through hole 1131b.

[0133] In addition, even if there is no blockage, when the flow rate of the first through hole 1111a in the first stator core 111a is greater than the flow rate of the first through hole 1111b, the flow rate of the coolant can be redistributed through the second stator core 112b, that is, part of the coolant in the first through hole 1111a flows into the second through hole 1131a through the second gap 150 of the second stator core 112b, and another part of the coolant in the first through hole 1111a flows into the second through hole 1131b through the second gap 150 of the second stator core 112b, thereby avoiding the problem of insufficient coolant in the third stator core 113. The same is true when the flow rate of the first through hole 1111b in the first stator core 111a is greater than the flow rate of the first through hole 1111a.

[0134] It should be noted that the second stator core 112b can adopt the same structure as the second stator core 112a, or the second stator core 112b can adopt a structure different from the second stator core 112a, as long as the second gap 150 formed by the second stator core 112b can be used to connect the first stator core 111a and the third stator core 113.

[0135] It should also be noted that Fig.12 and Fig.15 It is only schematically shown that the distance between the second through hole 1131a and the axis O of the motor 11, the distance between the second through hole 1131b and the axis O of the motor 11 are different from the distance between the first through hole 1111b and the axis O of the motor 11, and the distance between the second through hole 1131a and the axis O of the motor 11 is different from the distance between the second through hole 1131b and the axis O of the motor 11, which does not represent the specific position of the axis O of the motor 11.

[0136] Please continue reading Fig.11 In one embodiment, the thickness of the second stator core 112 b along the axial direction O of the motor 11 is less than the thickness of any one of the first stator core 111 a and the third stator core 113 .

[0137] In the embodiment of the present application, the second stator core 112b mainly plays the role of distributing the coolant. The axial thickness of the second stator core 112b is less than the thickness of any one of the first stator core 111a and the third stator core 113, so that the coolant can flow from the second stator core 112b to the third stator core 113 more quickly. In addition, the influence on the overall electromagnetic performance of the multiple stator cores 110 can also be reduced.

[0138] In the embodiment of the present application, the axial thickness of the third stator core 113 is relatively large, and the multiple second through holes 1131 of the third stator core 113 can receive coolant through the second gap 150. The coolant can cool the third stator core 113 with a relatively large axial thickness, which is beneficial to expanding the contact area between the coolant and the multiple stator cores 110.

[0139] Please continue reading Fig.11 , Fig.12 and Fig.15 In one embodiment, the plurality of stator cores 110 further include a fourth stator core 114, and along the axial direction O of the motor 11, a third stator core 113 is located between the second stator core 112b and the fourth stator core 114. One end of the plurality of wires 131 is exposed from each winding slot of the fourth stator core 114.

[0140] A fourth stator core 114 includes a plurality of third through holes 1141, and the plurality of third through holes 1141 penetrates the fourth stator core 114. The extension direction of the plurality of third through holes 1141 intersects with the axis O of the motor 11. Along the axial direction O of the motor 11, one opening of each third through hole 1141 is arranged adjacent to another opening of the second through hole 1131b in a third stator core 113. Along the radial direction R of the motor 11, the distance between each third through hole 1141 and the axis O of the motor 11 decreases from one opening of each third through hole 1141 toward another opening of each third through hole 1141.

[0141] In the embodiment of the present application, the fourth stator core 114, the third stator core 113 and the second stator core 112b are arranged in sequence along the axial direction O of the motor 11. Among them, the fourth stator core 114 is closer to one end of the plurality of wires 131 than the third stator core 113 along the axial direction O of the motor 11, and one end of the plurality of wires 131 is exposed in each winding slot 1100 of the fourth stator core 114. The fourth stator core 114 includes a plurality of third through holes 1141, one of the third through holes 1141 is connected to the second through hole 1131b of the third stator core 113, and each of the third through holes 1141 can receive the coolant transmitted by the third stator core 113. Different from the extension direction of the first through hole 1111 and the second through hole 1131, the extension direction of the third through hole 1141 of the fourth stator core 114 intersects with the axis O of the motor 11, and the spacing between the third through hole 1141 and one end of the multiple wires 131 along the radial direction R of the motor 11 gradually decreases, so that the coolant can be sprayed from the third through hole 1141 to the outside of one end of the multiple wires 131, thereby cooling the end of the winding 130 and improving the utilization rate of the coolant.

[0142] Please continue reading Fig.11 , Fig.12 and Fig.15 In one embodiment, a fourth stator core 114 further includes a plurality of fourth through holes 1142, and the plurality of fourth through holes 1142 penetrate the fourth stator core 114 along the axial direction O of the motor 11. The maximum distance between each fourth through hole 1142 and the axis O of the motor 11 along the radial direction R of the motor 11 is smaller than the minimum distance between each third through hole 1141 and the axis O of the motor 11. An opening of each fourth through hole 1142 is arranged adjacent to a second through hole 1131 of a third stator core 113 along the axial direction O of the motor 11.

[0143] In the embodiment of the present application, the plurality of fourth through holes 1142 of the fourth stator core 114 extend along the axial direction O of the motor 11, and each of the fourth through holes 1142 is connected to the second through hole 1131a of the third stator core 113, and the fourth through holes 1142 can receive the coolant from the third stator core 113. Along the radial direction R of the motor 11, each of the fourth through holes 1142 is closer to the axis O of the motor 11 than each of the third through holes 1141, and the fourth through holes 1142 cooperate with the third through holes 1141 to achieve three-dimensional cooling of the plurality of wires 131, and comprehensively improve the heat dissipation effect on the end of the winding 130.

[0144] See also Fig.16 and Fig.17 , Fig.16 This is a partial exploded view of the motor 11 provided in the embodiment of the present application. Fig.17 This is a partial cross-sectional view of the motor 11 provided in the embodiment of the present application. Fig.17 The black dashed line and the adjacent arrows in the figure represent the flow path and direction of the coolant, respectively.

[0145] In one embodiment, the first stator core 111a, the second stator core 112b, the third stator core 113 and the fourth stator core 114 constitute a stator core group 101, and the motor 11 includes the second stator core 112a and two stator core groups 101, and the two stator core groups 101 are axially symmetrical about the second stator core 112a.

[0146] In the embodiment of the present application, the two stator core groups 101 are symmetrically arranged on both sides of the second stator core 112a along the axial direction O of the motor 11, and the cooling channels formed are as follows: Fig.17 As shown, it is helpful to alleviate the blockage problem on both sides of the multiple stator cores 110, realize the reasonable distribution of the coolant on both sides of the multiple stator cores 110, and improve the cooling efficiency of the two ends of the multiple wires. In addition, the two stator core groups 101 do not interfere with each other, and the flow channels in the two stator core groups 101 are independent of each other, which can avoid the coolant flowing through one stator core group 101 before flowing to the other stator core group 101, ensuring the uniformity of cooling the two stator core groups 101.

[0147] It should be noted that Fig.17It is only schematically shown that the distance between the first through hole 1111a and the axis O of the motor 11 is different from the distance between the first through hole 1111b and the axis O of the motor 11, the distance between the second through hole 1131a and the axis O of the motor 11, the distance between the second through hole 1131b and the axis O of the motor 11 are different from the distance between the first through hole 1111b and the axis O of the motor 11, and the distance between the second through hole 1131a and the axis O of the motor 11 is different from the distance between the second through hole 1131b and the axis O of the motor 11, which does not represent the specific position of the axis O of the motor 11.

[0148] The motor, powertrain and vehicle provided in the embodiments of the present application are described in detail above. Specific examples are used herein to illustrate the principles and embodiments of the present application. The description of the above embodiments is only used to help understand the method and core idea of ​​the present application. At the same time, for those of ordinary skill in the art, according to the idea of ​​the present application, there will be changes in the specific embodiments and application scope. In summary, the content of this specification should not be understood as limiting the present application.

Claims

1. A motor, characterized in that: The motor comprises a motor housing and a plurality of stator cores, wherein the motor housing is used to accommodate the plurality of stator cores, a plurality of winding slots of each stator core are sequentially arranged along the circumference of the motor, each winding slot is used to accommodate a plurality of conductors, and the plurality of stator cores comprises: Two first stator cores, each of the first stator cores comprises a plurality of first through holes, the plurality of first through holes penetrate each of the first stator cores along the axial direction of the motor, and the plurality of first through holes of each of the first stator cores are spaced from the plurality of winding slots of each of the first stator cores; a second stator core, wherein the second stator core is arranged between the two first stator cores along the axial direction of the motor; At least a portion of the outer circumferential surface of the one second stator core forms a first gap with the two first stator cores and the one motor housing, and along the axial direction of the motor, an opening of one of the first through holes in each of the first stator cores and an opening of another of the first through holes are exposed to the one first gap, and along the radial direction of the motor, the maximum spacing between the one first through hole and the axis of the motor is smaller than the minimum spacing between the other first through hole and the axis of the motor.

2. The motor according to claim 1, characterized in that The outer diameter of at least part of the outer circumference of the second stator core along the radial direction of the motor is greater than the maximum distance between each of the winding slots and the axis of the motor, and the outer diameter of at least part of the outer circumference of the second stator core along the radial direction of the motor is less than the maximum distance between the first through hole and the axis of the motor.

3. The motor according to claim 1, characterized in that The first through hole is arranged between two adjacent winding slots along the circumferential direction of the motor, and the maximum distance between the first through hole and the axis of the motor along the radial direction of the motor is less than or equal to the maximum distance between each winding slot and the axis of the motor; At least a portion of the outer circumferential surface of the second stator core includes a first groove, and the first groove penetrates the second stator core along the axial direction of the motor. An opening of the first groove in the radial direction of the motor faces the inner circumferential surface of the motor housing, and at least a portion of the projection of the first through hole in the axial direction of the motor is located within the projection of the first groove.

4. The motor according to claim 3, characterized in that A minimum width of the first groove along the circumferential direction of the motor is greater than an inner diameter of each of the first through holes.

5. The motor according to claim 3 or 4, characterized in that: A width of the opening of the first groove along the circumferential direction of the motor is greater than a width of the groove bottom of the first groove.

6. The motor according to any one of claims 3 to 5, characterized in that: A maximum distance between the one first groove and the axis of the motor along the radial direction of the motor is less than or equal to a maximum distance between the other first through hole and the axis of the motor.

7. The motor according to any one of claims 3 to 6, characterized in that: At least part of the outer circumferential surface of the second stator core includes a plurality of the first grooves, and the plurality of first grooves are arranged in sequence along the circumferential direction of the motor, each of the first grooves is used to form the first gap, and the ratio of the number of the first grooves of the second stator core to the number of the first through holes of each of the first stator cores is less than or equal to 1 / 2.

8. The motor according to any one of claims 1 to 7, characterized in that: The inner circumferential surface of the motor housing includes a second groove, the second groove is recessed away from the second stator core in the radial direction of the motor, and the second groove extends along the circumferential direction of the motor.

9. The motor according to any one of claims 1 to 8, characterized in that: The inner circumferential surface of the motor housing includes a liquid inlet, and the distance between the center of the liquid inlet and the second stator core along the axial direction of the motor is smaller than the distance between the center of the liquid inlet and the two first stator cores.

10. The motor according to any one of claims 1 to 9, characterized in that: The thickness of the second stator core along the axial direction of the motor is smaller than the thickness of any one of the two first stator cores.

11. The motor according to any one of claims 1 to 10, characterized in that: The plurality of stator cores further include another second stator core and a third stator core, and the another second stator core is arranged between one first stator core and one third stator core along the axial direction of the motor; The third stator core comprises a plurality of second through holes, the plurality of second through holes penetrate the third stator core along the axial direction of the motor, and the maximum distance between the plurality of second through holes and the axis of the motor along the radial direction of the motor is smaller than the maximum distance between the other first through hole and the axis of the motor; At least a portion of the outer circumferential surface of the other second stator core forms a second gap with the first stator core, the third stator core, and the motor housing. Along the axial direction of the motor, another opening of the first through hole, another opening of the other first through hole, an opening of the second through hole, and an opening of another second through hole are exposed to the second gap. Along the radial direction of the motor, the maximum spacing between the second through hole and the axis of the motor is smaller than the minimum spacing between the other second through hole and the axis of the motor.

12. The motor according to claim 11, characterized in that The plurality of stator cores further include a fourth stator core, the third stator core is located between the second stator core and the fourth stator core along the axial direction of the motor, and the one end of the plurality of wires is exposed from each winding slot of the fourth stator core; The fourth stator core includes a plurality of third through holes, the plurality of third through holes penetrate the fourth stator core, an extension direction of the plurality of third through holes intersects with the axis of the motor, an opening of each of the third through holes is arranged adjacent to another opening of another second through hole in the third stator core along the axial direction of the motor, and a distance between each of the third through holes and the axis of the motor along the radial direction of the motor decreases from one opening of each of the third through holes toward another opening of each of the third through holes.

13. The motor according to claim 12, characterized in that The fourth stator core also includes a plurality of fourth through holes, which penetrate the fourth stator core along the axial direction of the motor, and the maximum distance between each of the fourth through holes and the axis of the motor along the radial direction of the motor is smaller than the minimum distance between each of the third through holes and the axis of the motor, and an opening of each of the fourth through holes is arranged adjacent to the second through hole of the third stator core along the axial direction of the motor.

14. A powertrain, characterized in that: The power assembly includes a motor controller, a reducer and a motor as described in any one of claims 1 to 13, wherein the motor controller is used to provide electrical energy to the windings of the motor, and the motor is used to drive and connect to the reducer.

15. A vehicle, characterized in that: The vehicle includes a frame, a battery pack and a powertrain as described in claim 14, wherein the frame is used to fix the battery pack and the powertrain, the battery pack is used to supply power to the motor through the motor controller, and the powertrain is used to drive the wheels of the vehicle through the motor.

Images