Motor for driving vehicle, power assembly and vehicle

Abstract

The invention provides a motor for driving a vehicle, a power assembly and the vehicle. The motor comprises a motor shell and a plurality of stator cores, the motor shell is used for containing the stator cores, and the stator cores are sequentially and adjacently arranged in the axial direction of the motor. The outer peripheral surface of each stator core includes a plurality of grooves and a plurality of protrusions. The plurality of protrusions are arranged at intervals in the circumferential direction of the motor, each groove is arranged between two protrusions in the circumferential direction of the motor, and each protrusion protrudes towards the inner wall of the motor shell in the radial direction of the motor. The stator iron core comprises a first stator iron core and a second stator iron core which are adjacently arranged, and the projection of at least one protrusion in the first stator iron core does not coincide with the projection of each protrusion in the second stator iron core in the axial direction of the motor. By adjusting the position arrangement of the protrusions, it is avoided that cooling liquid is completely blocked by the protrusions when flowing on the outer circumferential faces of the stator iron cores, the problem that the stator iron cores are cooled unevenly is solved, the working performance of a power assembly is improved, 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 for driving 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. However, the current heat dissipation solution for the motor has the problem of insufficient local cooling, 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 for driving a vehicle.

[0004] In a first aspect, an embodiment of the present application provides a motor for driving a vehicle. The motor includes a motor housing and a plurality of stator cores, wherein the motor housing is used to accommodate the plurality of stator cores, and the plurality of stator cores are arranged adjacent to each other in the axial direction of the motor. The outer peripheral surface of each stator core includes a plurality of grooves and a plurality of protrusions.

[0005] In each stator core, a plurality of protrusions are arranged at intervals along the circumference of the motor, each groove is arranged between two protrusions along the circumference of the motor, and each protrusion protrudes toward an inner wall of a motor housing along the radial direction of the motor.

[0006] The plurality of stator cores include a first stator core and a second stator core. The first stator core and the second stator core are arranged adjacent to each other along the axial direction of the motor. The projection of at least one protrusion in the first stator core and the projection of each protrusion in the second stator core along the axial direction of the motor do not overlap.

[0007] In the embodiment of the present application, when the motor is in operation, alternating current is passed through the motor winding to generate alternating magnetic flux, and the hysteresis loss and eddy current loss generated by the alternating magnetic flux in the multiple stator cores will cause the heat generated by the multiple stator cores to increase continuously. In order to achieve temperature rise control of the multiple stator cores, coolant is usually delivered to the outer peripheral surface of the multiple stator cores.

[0008] However, if the coolant is blocked by the protrusions of multiple stator cores during its flow, it will be difficult for the coolant to cover the outer peripheral surfaces of multiple stator cores along the circumference of the motor, which will lead to uneven cooling of multiple stator cores. To solve the above problem, the embodiment of the present application forms cooling channels on the outer peripheral surfaces of multiple stator cores by adjusting the position arrangement of the protrusions of different stator cores, so that the coolant can flow between different grooves, expand the contact area between the coolant and the stator core, and improve the cooling efficiency.

[0009] In an embodiment of the present application, when the coolant is delivered to the outer circumferential surfaces of the first stator core and the second stator core, if the projections of each protrusion of the first stator core and each protrusion of the second stator core along the axial direction of the motor coincide, most of the coolant will be blocked by the protrusions of the first stator core and the protrusions of the second stator core, and the cooling range will be limited to one groove and one groove arranged adjacently in the first stator core and the second stator core, which makes it difficult to alleviate the problem of insufficient local cooling of the stator core.

[0010] The embodiment of the present application adjusts the axial projections of at least one protrusion of the first stator core and each protrusion of the second stator core to not overlap, which is equivalent to that at least one protrusion of the first stator core and each protrusion of the second stator core are arranged at intervals along the circumference of the motor. The coolant can continue to flow in the dislocated space between the two protrusions whose axial projections do not overlap, which is beneficial to reducing the resistance of the coolant on the moving path, expanding the heat dissipation area of ​​the coolant, and alleviating the problem of insufficient local cooling of the stator core.

[0011] In one embodiment, the number of protrusions of a first stator core is equal to the number of protrusions of a second stator core. The projection of the protrusions in a first stator core and the projection of the protrusions in a second stator core along the axial direction of the motor do not overlap.

[0012] In an embodiment of the present application, the protrusions and grooves at different positions form a labyrinth-like cooling channel on the outer peripheral surface of the stator core, which is beneficial to expand the coverage of the coolant on the outer peripheral surface of the stator core. The number of protrusions of the first stator core is equal to the number of protrusions of the second stator core, and the first stator core and the second stator core can use the same core punching sheet, which is beneficial to reduce the processing difficulty and cost. It can be understood that the first stator core and the second stator core can also use different core punching sheets, as long as the projections of the protrusions of the first stator core and the protrusions of the second stator core along the axial direction of the motor do not overlap.

[0013] In one embodiment, a first stator core and a second stator core include a plurality of core punching sheets, and the outer peripheral surface of each core punching sheet includes a plurality of sub-protrusions. In each stator core, the plurality of sub-protrusions of each core punching sheet are arranged at intervals along the circumference of the motor. The plurality of sub-protrusions of a portion of the core punching sheets along the axial direction of the motor are stacked to form the plurality of protrusions of the first stator core, and the plurality of sub-protrusions of another portion of the core punching sheets along the axial direction of the motor are rotated relative to the plurality of sub-protrusions of another portion of the core punching sheets and then stacked to form the plurality of protrusions of the second stator core.

[0014] In an embodiment of the present application, a portion of the core punching sheets are stacked along the axial direction of the motor to form a first stator core. During the stacking process, it is necessary to use a spiral stacking method to correct the same-plate difference of different stator cores. Among them, the same-plate difference refers to the difference in thickness of each observation point along the same direction of the same core punching sheet, and spiral stacking refers to rotating the core punching sheets while stacking the core punching sheets to avoid direct stacking of larger or smaller thickness parts of different core punching sheets to cause a larger same-plate difference.

[0015] The embodiment of the present application uses the idea of ​​spiral overlap correction of the same plate difference to achieve that the axial projection of the protrusion in the first stator core does not overlap with the axial projection of the protrusion in the second stator core.

[0016] Specifically, the sum of the axial lengths of the protrusions of the first stator core and the protrusions of the second stator core is equal to the sum of the axial lengths of the first stator core and the second stator core. Considering the lamination process of the core punching sheets, it can be deduced that the axial length of the protrusions of each stator core is equal to the axial length of the stator core. If the first stator core and the second stator core are laminated in the conventional manner, the axial projections of the laminated protrusions of the first stator core and the second stator core will overlap, which will make it difficult for the coolant to bypass the protrusions of the first stator core and the second stator core and continue to flow. In the embodiment of the present application, during the lamination process of multiple stator cores, the protrusion of the next stator core is rotated to be misaligned with the protrusion of the previous stator core, which can not only overcome the same plate difference, but also enable the protrusion of one stator core to guide the coolant to the groove of one stator core and the groove of another stator core, so that the coolant flows along the circumference of the motor on the outer peripheral surface of multiple stator cores.

[0017] In one embodiment, the plurality of stator cores further comprises a third stator core, and the third stator core and the first stator core are arranged on both sides of a second stator core along the axial direction of the motor. A projection of at least one protrusion in the third stator core and a projection of at least one protrusion in the second stator core along the axial direction of the motor overlap.

[0018] In an embodiment of the present application, the third stator core and the second stator core are arranged adjacent to each other along the axial direction of the motor, and an axial projection of at least one protrusion of the third stator core coincides with an axial projection of at least one protrusion of the second stator core, so that an axial projection of at least one groove of the third stator core coincides with an axial projection of at least one groove of the second stator core, so that the coolant flowing between the first stator core and the second stator core can also flow to the groove of the third stator core through the groove of the second stator core.

[0019] In one embodiment, the number of protrusions of a second stator core is equal to the number of protrusions of a third stator core. The projection of the plurality of protrusions in a third stator core along the axial direction of the motor coincides with the projection of the plurality of protrusions in a second stator core.

[0020] In an embodiment of the present application, the number of protrusions on the second stator core is equal to the number of protrusions on the third stator core, and the axial projections of the protrusions on the second stator core and the protrusions on the third stator core overlap, which is beneficial to reducing the flow resistance of the coolant between the second stator core and the third stator core.

[0021] In one embodiment, the plurality of stator cores further include a fourth stator core, and the number of protrusions of the fourth stator core is equal to the number of protrusions of the first stator core. At least two stator cores are arranged between the fourth stator core and the first stator core along the axial direction of the motor. The projection of the plurality of protrusions in the fourth stator core along the axial direction of the motor overlaps with the projection of the plurality of protrusions in the first stator core. The projection of the plurality of protrusions of at least one of the at least two stator cores along the axial direction of the motor does not overlap with the projection of the plurality of protrusions of the first stator core.

[0022] In an embodiment of the present application, the axial projections of the multiple protrusions of the first stator core and the multiple protrusions of the fourth stator core overlap, at least two other stator cores are located between the first stator core and the fourth stator core, and the grooves of at least one stator core in the middle position gather the coolant and then guide the coolant to the grooves of the first stator core and the grooves of the fourth stator core respectively. The positional relationship between the protrusions of different stator cores further increases the complexity of the cooling flow channel, which is beneficial to improving the turbulent effect of the protrusions on the coolant. The coolant in the groove of at least one stator core in the middle position is difficult to flow out of the stator core directly along the axial direction of the motor, which is beneficial to improving the cooling efficiency of the stator core.

[0023] In one embodiment, the number of protrusions of one stator core among the at least two stator cores is greater than the number of protrusions of a first stator core and the number of protrusions of a fourth stator core.

[0024] In the embodiment of the present application, a stator core is located between the first stator core and the fourth stator core, and the number of protrusions of a stator core is different from the protrusions of the first stator core and the protrusions of the fourth stator core, so the axial projection of at least one protrusion of a stator core does not overlap with the protrusions of the first stator core and the protrusions of the fourth stator core. The different numbers of protrusions of different stator cores are conducive to increasing the complexity of the cooling flow channels on the outer peripheral surfaces of multiple stator cores, playing a turbulent role on the coolant, and enhancing the heat dissipation efficiency.

[0025] In one embodiment, the width of at least one groove in each stator core along the circumferential direction of the motor is greater than the width of each protrusion.

[0026] In the embodiment of the present application, the circumferential length of the protrusion is smaller than the circumferential length of the groove, which is beneficial to reducing the area occupied by the protrusion on the outer peripheral surface of the stator core and increasing the actual cooling area of ​​the coolant, and can also reduce the contact area between the protrusion and the motor housing, thereby avoiding wear between the stator core and the motor housing during installation.

[0027] In one embodiment, the width of each groove in a first stator core along the axial direction of the motor is equal to the width of each protrusion in a first stator core.

[0028] In an embodiment of the present application, after flowing to the protrusion of the first stator core, the coolant can flow directly to the groove of the first stator core along the edge of the protrusion of the first stator core, which is beneficial to reducing the flow resistance of the coolant on the outer peripheral surface of the same stator core.

[0029] In one embodiment, the thickness of each stator core along the axial direction of the motor is smaller than the length of each protrusion in each stator core along the circumferential direction of the motor.

[0030] In the embodiment of the present application, the axial thickness of each stator core is relatively small, which is convenient for increasing the number of stator cores, and the different layouts of protrusions and grooves in multiple stator cores are realized by spiral stacking of core punching sheets to meet the heat dissipation requirements of the motor in different application scenarios. The circumferential length of each protrusion is relatively large, which is conducive to improving the stability of the fixed connection between the stator core and the motor housing.

[0031] In one embodiment, each stator core includes a center hole and a plurality of winding slots, and the plurality of winding slots are used to accommodate windings. Among them, a center hole of one of the two adjacent stator cores is connected to a center hole of the other stator core along the axial direction of the motor. Each winding slot of one of the two adjacent stator cores is connected to a winding slot of the other stator core along the axial direction of the motor, and the width of each winding slot along the circumferential direction of the motor is less than the width of a protrusion.

[0032] In an embodiment of the present application, the center holes of two adjacently arranged stator cores are connected, and the center holes are used to accommodate the rotor or motor shaft of the motor. The winding slots of two adjacently arranged stator cores are connected, and the winding slots are used to accommodate the windings. Since the protrusion can change the flow direction of the coolant, the circumferential width of the protrusion is larger than the circumferential width of the winding slot, so that the protrusion plays a buffering role for the flow of the coolant, avoids a sharp change in the flow direction of the coolant, and reduces the loss of the coolant during the flow process.

[0033] In one embodiment, a motor housing includes an axial housing, and the axial housing is arranged adjacent to a stator core along the axial direction of the motor. The outer peripheral surface of each stator core includes a plurality of through holes, and each through hole penetrates a protrusion along the axial direction of the motor. An axial housing is used to fix and connect a plurality of fixing members, and each fixing member is used to pass through at least one through hole along the axial direction of the motor. The length of the winding in each winding slot along the axial direction of the motor along the axial direction of the motor is greater than the sum of the thicknesses of the plurality of stator cores.

[0034] In an embodiment of the present application, a plurality of protrusions located on the outer peripheral surface of the stator core are used to achieve axial fixation of the stator core and the axial housing. Specifically, a plurality of protrusions protrude toward the inner wall of the motor housing, and each protrusion is fixed to the stator core and the axial housing along the axial direction of the motor by a through hole provided by a fixing member. In an application scenario where the stator core and the motor housing are fixed along the axial direction of the motor, the embodiment of the present application adjusts the layout of the protrusions of different stator cores to achieve the flow of coolant in different grooves along the circumference of the motor, thereby avoiding the coolant being completely blocked by the protrusions. Compared with the fixing method of the stator core and the motor housing by interference fit, the embodiment of the present application achieves the fixation of the stator core and the motor housing by bolt connection, which is beneficial to reduce the loss of the stator core during installation and alleviate the problem of local stress.

[0035] In one embodiment, a motor housing includes a circumferential housing, and the circumferential housing surrounds the outer circumference of a plurality of stator cores. Each groove in each stator core forms a gap with the circumferential housing. Each gap in the first stator core is used to connect to a gap in the second stator core along the axial direction of the motor to form an axial flow channel.

[0036] In an embodiment of the present application, the motor housing can be a groove-shaped housing, that is, the axial housing is the axial groove bottom of the groove-shaped housing, and the circumferential housing is the circumferential groove wall of the groove-shaped housing. The cavity enclosed by the axial housing and the circumferential housing is used to accommodate multiple stator cores.

[0037] In an embodiment of the present application, the distance between each groove and the circumferential shell along the radial direction of the motor is greater than the distance between each protrusion and the circumferential shell, and the coolant can flow in the gap between each groove and the circumferential shell. Among them, the groove of the first stator core and the groove of the second stator core are used to form an axial flow channel. Specifically, each gap of the first stator core is connected to a gap of the second stator core along the axial direction of the motor, so that the coolant can flow back and forth on the outer peripheral surface of the first stator core and the second stator core, which is conducive to reducing the resistance of the coolant to flow between the first stator core and the second stator core, and realizing the cooling of the first stator core and the second stator core by the coolant along the circumference of the motor.

[0038] In the embodiment of the present application, the formation of the axial flow channel only involves the fixed structure and outer peripheral surface of the different stator cores themselves, and no additional components are used, which is conducive to the reuse of the raised structure and can also reduce the changes to other structures in the motor, which is conducive to reducing design and processing costs.

[0039] In one embodiment, the length of each axial flow channel along the circumferential direction of the motor is smaller than the length of each groove in a first stator core or a second stator core.

[0040] In an embodiment of the present application, the axial projections of the multiple protrusions in the first stator core do not overlap with the axial projections of the multiple protrusions in the second stator core. Correspondingly, the axial projections of the multiple grooves in the first stator core do not completely overlap with the axial projections of the multiple grooves in the second stator core. Each axial flow channel is a connecting area of ​​the grooves of different stator cores, so the circumferential length of each axial flow channel is less than the length of each groove in the first stator core or the second stator core. The circumferential length of the axial flow channel is relatively small, which facilitates the staggered arrangement of the protrusions of the first stator core and the protrusions of the second stator core.

[0041] In one embodiment, a circumferential housing includes a through hole, and the through hole is used to guide the coolant in an internal flow channel of the circumferential housing to a groove. In which, a through hole is arranged at intervals with a protrusion along the axial direction of the motor, and a through hole is arranged at intervals with an axial flow channel along the circumference of the motor.

[0042] In the embodiment of the present application, the coolant in the internal flow channel flows to the outer peripheral surface of the stator core through the flow hole. The projection of the flow hole along the radial direction of the motor and the projection along the axial direction of the motor are arranged at intervals, so that the flow hole can directly guide the coolant to the groove, and the flow hole is also arranged at intervals with the axial flow channel along the circumference of the motor, so that the coolant falling into the groove can directly move to both sides along the circumference of the motor, reducing the obstruction to the coolant.

[0043] In one embodiment, an opening of a through hole is directed from a groove of one stator core toward a groove of another stator core, and one stator core is arranged adjacent to the other stator core along the axial direction of the motor.

[0044] In the embodiment of the present application, taking the first stator core and the second stator core as an example, by adjusting the opening direction of the flow hole, the initial movement direction of the coolant after flowing out of the flow hole is directed from the groove of the first stator core to the groove of the second stator core, which is beneficial to improving the movement rate of the coolant between the protrusion of the first stator core and the protrusion of the second stator core.

[0045] In one embodiment, the distance between a through hole and an outer circumferential surface of a stator core excluding each protrusion in the radial direction of the motor is smaller than the length of each protrusion.

[0046] In the embodiment of the present application, the coolant flowing out of the through-hole will not flow directly to the protrusion, but will flow to the outer peripheral surface of the stator core except the protrusion. The radial distance between the through-hole and the outer peripheral surface of the stator core is relatively close, which can shorten the moving distance of the coolant between the through-hole and the stator core, and is conducive to improving the flow rate of the coolant.

[0047] In one embodiment, a circumferential housing includes an internal flow channel, an internal flow channel is arranged between two protrusions along the circumference of the motor, and an internal flow channel extends along the axial direction of the motor. A through hole runs through the internal flow channel, and the ratio of the inner diameter of the through hole to the inner diameter of the internal flow channel is greater than or equal to 0.1 and less than or equal to 0.3.

[0048] In the embodiment of the present application, if the inner diameter of the flow hole is too large, it will not be conducive to forming a larger flow pressure in the internal flow channel, which will further reduce the flow rate of the coolant and have a negative impact on the cooling efficiency.

[0049] In one embodiment, a circumferential housing further comprises another through-hole, which is used to guide part of the coolant in an internal flow channel of a circumferential housing to the end of the winding, wherein the projection of the other through-hole along the radial direction of the motor does not overlap with the plurality of stator cores.

[0050] In the embodiment of the present application, part of the coolant flows to one end of the winding through another flow hole, thereby cooling and dissipating the heat of the winding, which is beneficial to reducing the heat loss of the winding.

[0051] In one embodiment, a circumferential shell includes a plurality of internal flow channels, each of which is spaced apart along the circumference of the motor and is located between two different protrusions.

[0052] In the embodiment of the present application, increasing the number of internal flow channels is beneficial to increasing the flow rate of the coolant. The multiple internal flow channels are distributed between different protrusions, which can promote the coolant to flow around the outer peripheral surface of the stator core.

[0053] In the 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, the motor controller is used to provide electrical energy to the motor, the motor is used to transmit and connect the reducer, and an internal flow channel of a housing is used to transport coolant to the outer peripheral surface of multiple stator cores.

[0054] In the embodiment of the present application, the motor as described in the first aspect is used in the powertrain, which can expand the contact area between the coolant and the stator core, so that the working efficiency and safety performance of the motor are enhanced, which is beneficial to improving the power density of the powertrain and ensuring the safety performance 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, using the powertrain as described in the second aspect in the vehicle is beneficial to improving the heat dissipation effect of the powertrain and improving the performance of the entire 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 structural schematic diagram of a motor provided in an embodiment of the present application;

[0061] Figure 4 It is a structural schematic diagram of a stator core provided in an embodiment of the present application;

[0062] Figure 5 is a partial structural schematic diagram of a motor provided in an embodiment of the present application;

[0063] Figure 6 is another partial structural schematic diagram of a motor provided in an embodiment of the present application;

[0064] Figure 7 It is a structural schematic diagram of an iron core punching sheet provided in an embodiment of the present application;

[0065] Figure 8 It is another structural schematic diagram of the core punching sheet provided in the embodiment of the present application;

[0066] Fig. 9 is another partial structural schematic diagram of a motor provided in an embodiment of the present application;

[0067] Fig.10 is another structural schematic diagram of a motor provided in an embodiment of the present application;

[0068] Fig.11 is another structural schematic diagram of the stator core provided in an embodiment of the present application;

[0069] Fig.12 is another partial structural schematic diagram of a motor provided in an embodiment of the present application;

[0070] Fig.13 It is another partial structural schematic diagram of the motor provided in an embodiment of the present application. DETAILED DESCRIPTION

[0071] 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.

[0072] For ease of understanding, the relevant technical terms involved in the embodiments of the present application are explained and described below.

[0073] Same plate difference: refers to the thickness difference of each measuring point along the same direction of the same steel plate, which can be used to indicate the surface flatness and processing accuracy of the steel plate.

[0074] The current motor has the problem of insufficient local cooling of the stator core. An embodiment of the present application provides a motor, which includes a motor housing and multiple stator cores. A motor housing is used to accommodate multiple stator cores, and the multiple stator cores are arranged adjacent to each other in the axial direction of the motor. The outer peripheral surface of each stator core includes multiple grooves and multiple protrusions. Among them, in each stator core, multiple protrusions are arranged at intervals along the circumference of the motor, each groove is arranged between two protrusions along the circumference of the motor, and each protrusion protrudes toward the inner wall of a motor housing along the radial direction of the motor. The multiple stator cores include a first stator core and a second stator core, and the first stator core and the second stator core are arranged adjacent to each other in the axial direction of the motor. The projection of at least one protrusion in a first stator core along the axial direction of the motor does not overlap with the projection of each protrusion in a second stator core.

[0075] The protrusions and grooves of the embodiment of the present application cooperate to form a cooling channel, and the axial projections of at least one protrusion of different stator cores do not overlap, so as to prevent the coolant from being completely blocked by the protrusions when flowing on the outer peripheral surfaces of different stator cores, alleviate the problem of uneven cooling of the stator cores, and help improve the working performance of the powertrain and ensure the normal driving of the vehicle. The motor provided in the embodiment of the present application is applied to a powertrain, and the powertrain including the motor of the present application is applied to a vehicle.

[0076] See also Figure 1 , Figure 1A 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.

[0077] 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 winding of the motor 11. The motor 11 is connected to the reducer 13 in a transmission manner to drive the wheels 40 to rotate.

[0078] During the operation of the motor, the energy lost by the stator core of the motor will gradually turn into heat, causing the temperature of the stator core to continue to rise. If the cooling effect of the stator core is not good, it will not only directly damage the service life of the stator core and reduce the working efficiency of the motor, but also cause electrical failures and safety accidents in serious cases.

[0079] The embodiments of the present application improve the structure of the stator core in the motor, thereby expanding the heat dissipation area of ​​the coolant in the stator core, improving the cooling efficiency, and alleviating the problem of insufficient local cooling of the stator core, thereby reducing the negative impact on the motor and improving the safety performance of the vehicle.

[0080] See also Figures 3 to 5 , Figure 3 A schematic diagram of the structure of the motor 11 provided in an embodiment of the present application is shown in FIG. Figure 4 A schematic diagram of the structure of the stator core 110 provided in an embodiment of the present application is shown in FIG. Figure 5 A schematic diagram of a partial structure of the motor 11 provided in an embodiment of the present application.

[0081] like Figure 3 As shown, 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 stator cores 110 are arranged adjacent to each other in sequence along the axial direction O of the motor 11. Figure 3 and Figure 4As shown, the outer circumferential surface of each stator core 110 includes a plurality of protrusions 111 and a plurality of grooves 112. In each stator core 110, the plurality of protrusions 111 are arranged at intervals along the circumferential direction C of the motor 11, each groove 112 is arranged between two protrusions 111 along the circumferential direction C of the motor 11, and each protrusion 111 protrudes toward the inner wall of a motor housing 120 along the radial direction R of the motor 11.

[0082] like Figures 3 to 5 As shown, the plurality of stator cores 110 include a first stator core 110a and a second stator core 110b, and the first stator core 110a and the second stator core 110b are arranged adjacent to each other along the axial direction O of the motor 11. Along the axial direction O of the motor 11, the projection of at least one protrusion 111 in a first stator core 110a does not overlap with the projection of each protrusion 111 in a second stator core 110b.

[0083] In the embodiment of the present application, when the motor 11 is in operation, alternating current is passed through the winding 130 of the motor 11 to generate alternating magnetic flux, and the hysteresis loss and eddy current loss generated by the alternating magnetic flux in the multiple stator cores 110 will cause the heat generated by the multiple stator cores 110 to continue to increase. In order to achieve temperature rise control of the multiple stator cores 110, coolant is usually delivered to the outer peripheral surface of the multiple stator cores 110.

[0084] However, if the coolant is blocked by the protrusions 111 on the outer circumference of the multiple stator cores 110 during the flow, it will be difficult for the coolant to cover the outer circumference of the multiple stator cores 110 along the circumferential direction C of the motor 11, thereby causing uneven cooling of the multiple stator cores 110. To solve the above problem, the embodiment of the present application forms cooling channels on the outer circumference of the multiple stator cores 110 by adjusting the position arrangement of the protrusions 111 of different stator cores 110, so that the coolant can flow between different grooves 112, thereby expanding the contact area between the coolant and the stator core 110 and improving the cooling efficiency.

[0085] In the embodiment of the present application, taking the first stator core 110a and the second stator core 110b as examples, for the convenience of description, the protrusion 111 and the groove 112 of the first stator core 110a are respectively recorded as protrusion 111a and groove 112a, and the protrusion 111 and the groove 112 of the second stator core 110b are respectively recorded as protrusion 111b and groove 112b. When the coolant is delivered to the outer peripheral surface of the first stator core 110a and the second stator core 110b, if the projections of each protrusion 111a and each protrusion 111b along the axial direction O of the motor 11 coincide, most of the coolant will be blocked by the protrusion 111a and the protrusion 111b, and the cooling range is limited to one adjacent groove 112a and one groove 112b, which makes it difficult to alleviate the problem of insufficient local cooling of the stator core 110.

[0086] In the embodiment of the present application, by adjusting the axial projections of at least one protrusion 111a and each protrusion 111b not to overlap, it is equivalent to that at least one protrusion 111a and each protrusion 111b are arranged at intervals along the circumferential direction C of the motor 11, and the coolant can continue to flow in the dislocated space between the protrusions 111a and 111b whose axial projections do not overlap, which is conducive to reducing the resistance of the coolant on the moving path, expanding the heat dissipation area of ​​the coolant, and alleviating the problem of insufficient local cooling of the stator core 110. In one embodiment, the coolant is any one of ethylene glycol cooling oil, synthetic oil and mineral oil.

[0087] It should be noted that, in the embodiment of the present application, the projection along the axial direction O of the motor 11 refers to the projection along the axial direction O of the motor 11 on a projection plane perpendicular to the axial direction O of the motor 11. The projection plane along the axial direction O of the motor 11 is perpendicular to the axial direction O of the motor 11.

[0088] Please continue reading Figure 4 In one embodiment, the number of protrusions 111a of a first stator core 110a is equal to the number of protrusions 111b of a second stator core 110b. Along the axial direction O of the motor 11, the projection of the plurality of protrusions 111a in a first stator core 110a does not overlap with the projection of the plurality of protrusions 111b in a second stator core 110b.

[0089] In the embodiment of the present application, the relationship between the misalignment of the protrusions of the first stator core 110a and the second stator core 110b is applicable to each protrusion 111, and each protrusion 111 is distributed at different positions on the outer peripheral surface of the stator core 110. The protrusions 111 and the grooves 112 at different positions form a labyrinth-like cooling channel on the outer peripheral surface of the stator core 110, which is conducive to expanding the coverage of the coolant on the outer peripheral surface of the stator core 110. The number of protrusions 111a of the first stator core 110a is equal to the number of protrusions 111b of the second stator core 110b. The first stator core 110a and the second stator core 110b can use the same iron core punching sheet, which is conducive to reducing the difficulty and cost of processing. It can be understood that the first stator core 110a and the second stator core 110b can also use different iron core punching sheets, as long as the projections of the protrusions 111a and the protrusions 111b along the axial direction O of the motor 11 do not overlap.

[0090] Please continue reading Figure 4 and Figure 5In one embodiment, each protrusion 111a of a first stator core 110a is spaced from each protrusion 111b of a second stator core 110b along the circumferential direction C of the motor 11. The sum of the lengths of a protrusion 111a of a first stator core 110a and a protrusion 111b of a second stator core 110b along the axial direction O of the motor 11 is equal to the sum of the lengths of a first stator core 110a and a second stator core 110b.

[0091] In the embodiment of the present application, the protrusions 111a of the first stator core 110a and the protrusions 111b of the second stator core 110b are arranged alternately along the circumferential direction C of the motor 11. The staggered protrusions 111a and 111b form a maze-like cooling channel on the outer peripheral surfaces of different stator cores 110, thereby enhancing the effect of heat transfer by disturbing the coolant.

[0092] It should be noted that Figure 5 The first stator core 110a and the second stator core 110b shown in the figure show an arrangement of the stator core 110, wherein the specific number or axial length of the first stator core 110a and the second stator core 110b is not limited to Figure 5 For example, see Figure 6 , Figure 6 Another partial structural diagram of the motor 11 provided in the embodiment of the present application, two first stator cores 110a and two second stator cores 110b are arranged in sequence along the axial direction O of the motor 11, which also belongs to Figure 5 The arrangement of the stator cores 110 shown is such that the two first stator cores 110a can be regarded as a first stator core 110a with a doubled axial length, and the two second stator cores 110b can be regarded as two second stator cores 110b with a doubled axial length.

[0093] Please refer to Figure 3 and Figure 7 , Figure 7 A structural schematic diagram of a core punching sheet 115 provided in an embodiment of the present application. In one embodiment, a first stator core 110a and a second stator core 110b include a plurality of core punching sheets 115, and the outer peripheral surface of each core punching sheet 115 includes a plurality of sub-protrusions 1112. In each stator core 110, the plurality of sub-protrusions 1112 of each core punching sheet 115 are arranged at intervals along the circumferential direction C of the motor 11. The plurality of sub-protrusions 1112 of a portion of the core punching sheets 115 along the axial direction O of the motor 11 are stacked to form a plurality of protrusions 111a of the first stator core 110a, and the plurality of sub-protrusions 1112 of another portion of the core punching sheets 115 along the axial direction O of the motor 11 are rotated relative to the plurality of sub-protrusions 1112 of a portion of the core punching sheets 115 and then stacked to form a plurality of protrusions 111b of the second stator core 110b.

[0094] In the embodiment of the present application, along the axial direction O of the motor 11, a portion of the core punching sheets 115 are stacked to form a first stator core 110a. During the stacking process, it is necessary to use a spiral stacking method to correct the same-plate difference of different stator cores 110. The same-plate difference refers to the difference in thickness of each observation point along the same direction of the same core punching sheet 115, and spiral stacking refers to rotating the core punching sheet 115 while stacking the core punching sheets 115 to avoid direct stacking of the larger or smaller thickness parts of different core punching sheets 115 to cause a larger same-plate difference.

[0095] The embodiment of the present application uses the idea of ​​spiral overlap correction to achieve that the axial projection of the protrusion 111a in the first stator core 110a and the axial projection of the protrusion 111b in the second stator core 110b do not overlap.

[0096] Specifically, the sum of the axial lengths of the protrusions 111a and 111b is equal to the sum of the axial lengths of the first stator core 110a and the second stator core 110b. Considering the lamination process of the core punching sheets 115, it can be deduced that the axial length of the protrusion 111 of each stator core 110 is equal to the axial length of the stator core 110. If the first stator core 110a and the second stator core 110b are laminated in a conventional manner, the axial projections of the laminated protrusions 111a and 111b will overlap, which will make it difficult for the coolant to bypass the protrusions 111a and 111b and continue to flow. In the embodiment of the present application, during the stacking process of multiple stator cores 110, the protrusion 111 of the next stator core 110 is rotated to be misaligned with the protrusion 111 of the previous stator core, which not only overcomes the same plate difference, but also enables the protrusion 111 of one stator core 110 to guide the coolant to the groove 112 of one stator core 110 and the groove 112 of another stator core 110, thereby realizing the coolant flowing on the outer peripheral surface of the multiple stator cores 110 along the circumferential direction C of the motor 11.

[0097] like Figure 7 As shown, the plurality of sub-protrusions 1112 on one core punching sheet 115 are evenly arranged along the circumferential direction C of the motor. It should be noted that the arrangement of the plurality of sub-protrusions 1112 on one core punching sheet 115 is not limited to Figure 7 For example, see Figure 8 , Figure 8 Another structural schematic diagram of the core punching sheet 115 provided in the embodiment of the present application. Figure 8As shown, in one embodiment, the spacings between the multiple sub-protrusions 1112 of a core punching sheet 115 along the circumferential direction C of the motor may be different. It can be understood that the circumferential spacing between the multiple sub-protrusions 1112 of a core punching sheet 115 is only related to the circumferential length of the groove 112, and will not have a negative impact on the problem of insufficient local cooling of the stator core 110 in the embodiment of the present application. In practical applications, the angle of the core punching sheet 115 can be adjusted according to the arrangement characteristics of the sub-protrusions 1112.

[0098] It should also be noted that the number of sub-protrusions 1112 of a core punching sheet 115 is not limited to Figure 7 , illustratively, in one embodiment, a core punching sheet 115 may include 3 to 6 sub-protrusions 1112. The number of sub-protrusions 1112 needs to be controlled within a suitable range. If the number of sub-protrusions 1112 of a core punching sheet 115 is too large, it may cause the protrusions 111 of different stator cores 110 formed by stacking the core punching sheets 115 to be arranged too closely, so that the protrusions 111 occupy too much space in the grooves 112, and also increase the cost of processing and installation operations. If the number of sub-protrusions 1112 of a core punching sheet 115 is too small, it may have a negative impact on the connection stability between the stator core 110 and the motor housing 120.

[0099] Please continue reading Figure 3 and Figure 4 In one embodiment, the motor housing 120 includes an axial housing 121, and the axial housing 121 is arranged adjacent to a stator core 110 along the axial direction O of the motor 11. The outer peripheral surface of each stator core 110 includes a plurality of through holes 1111, and each through hole 1111 penetrates a protrusion 111 along the axial direction O of the motor 11. An axial housing 121 is used to fix and connect a plurality of fixing members 140, and each fixing member 140 is used to pass through at least one through hole 1111 along the axial direction O of the motor 11.

[0100] In the embodiment of the present application, a plurality of protrusions 111 located on the outer circumferential surface of the stator core 110 are used to achieve axial fixation of the stator core 110 and the axial housing 121. Specifically, the plurality of protrusions 111 protrude toward the inner wall of the motor housing 120, and each protrusion 111 is penetrated by a through hole 1111 provided by a fixing member 140 to fix the stator core 110 to the axial housing 121 along the axial direction O of the motor 11. In the application scenario where the stator core 110 and the motor housing 120 are fixed along the axial direction O of the motor 11, the layout of the protrusions 111 of different stator cores 110 is adjusted to achieve the flow of the coolant in different grooves 112 along the circumferential direction C of the motor 11, thereby preventing the coolant from being completely blocked by the protrusions 111.

[0101] In one embodiment, the through hole 1111 is a bolt hole, the fixing member 140 is a bolt, and the bolt is passed through the bolt hole along the axial direction O of the motor 11 and fixed to the axial housing 121, and the rotation of the stator core 110 is limited by the cooperation between the bolt and the bolt hole. Compared with the fixing method of the stator core 110 and the motor housing 120 by interference fit, the embodiment of the present application realizes the fixing of the stator core 110 and the motor housing 120 by bolt connection, which is conducive to reducing the loss of the stator core 110 during the installation process and alleviating the problem of local stress.

[0102] Please continue reading Figure 3 In one embodiment, along the axial direction O of the motor 11, each protrusion 111a of the first stator core 110a abuts against the axial housing 121. Along the axial direction O of the motor 11, the distance between each protrusion 111 of the other stator cores 110 except the first stator core 110a among the multiple stator cores 110 and one end surface 114 of the first stator core 110a facing the axial housing 121 is less than or equal to the distance between each protrusion 111 of the other stator cores 110 except the first stator core 110a among the multiple stator cores 110 and the axial housing 121.

[0103] In the embodiment of the present application, the protrusion 111a of the first stator core 110a directly contacts the axial housing 121 along the axial direction O of the motor 11, that is, the distance between the protrusion 111a of the first stator core 110a and the end face 114 is equal to the distance between the protrusion 111a of the first stator core 110a and the axial housing 121, so as to realize axial fixation of the stator core 110 and the motor housing 120.

[0104] In the embodiment of the present application, the first stator core 110a is closer to the end face 114 than the other stator cores 110. Under the premise that the protrusion 111a of the first stator core 110a is fixed to the axial housing 121, the protrusions 111 of the other stator cores 110 can be spaced apart from the axial housing 121, and the protrusions 111 of the other stator cores 110 mainly play a positioning role. In this case, the distance between the protrusions 111 of the other stator cores 110 and the end face 114 is equal to the distance between the protrusions 111 of the other stator cores 110 and the axial housing 121. Since the protrusions 111 of the other stator cores 110 are spaced apart from the axial housing 121, the space of the cooling channel formed by the protrusions 111 of the other stator cores 110 will not be occupied by the axial housing 121, which is conducive to improving the cooling efficiency.

[0105] In the embodiment of the present application, in order to enhance the stability of the fixed connection between the stator core 110 and the motor housing 120, the protrusions 111 of other stator cores 110 may also be abutted against the axial housing 121. In this case, the distance between the protrusions 111 of other stator cores 110 and the end surface 114 of the first stator core 110a facing the axial housing 121 is smaller than the distance between the protrusions 111 of other stator cores 110 and the axial housing 121. Please continue to refer to Figure 3 In one embodiment, the axial housing 121 includes a plurality of fixing columns 1211, each fixing column 1211 protrudes 111 toward one end surface 114 of the first stator core 110a along the axial direction O of the motor 11, and each fixing column 1211 is aligned with one protrusion 111 of the plurality of stator cores 110 along the axial direction O of the motor 11. The distance between the protrusions 111 of the plurality of stator cores 110 and the axial housing 121 can be adjusted by changing the axial lengths of different fixing columns 1211. Exemplarily, the axial length of the fixing column 1211 used to fix the first stator core 110a is less than or equal to the axial length of the fixing column 1211 used to fix the other stator cores 110, each protrusion 111a of the first stator core 110a is directly abutted against one fixing column 1211, and each protrusion 111 of the other stator cores 110 is spaced apart from or directly abutted against one fixing column 1211.

[0106] In one embodiment, the number of the fixing columns 1211 of the axial housing 121 is greater than or equal to 3, and the number of the fixing columns 1211 of the axial housing 121 is less than or equal to 6. In the embodiment of the present application, the protrusions 111 of some of the stator cores 110 in the multiple stator cores 110 can share the fixing columns 1211. If the number of the fixing columns 1211 and the protrusions 111 is too large, the cost of the motor housing 120 and the multiple stator cores 110 will increase. If the number of the fixing columns 1211 and the protrusions 111 is too small, the connection strength between the motor housing 120 and the multiple stator cores 110 will be reduced.

[0107] Please continue reading Figure 3 and Figure 5 In one embodiment, a motor housing 120 includes a circumferential housing 122, and the circumferential housing 122 surrounds the outer circumference of the plurality of stator cores 110. Each groove 112 in each stator core 110 forms a gap with a circumferential housing 122, and each gap in the first stator core 110a is used to connect to a gap in the second stator core 110b along the axial direction O of the motor 11 to form an axial flow channel 113.

[0108] In the embodiment of the present application, the motor housing 120 may be a groove-shaped housing, that is, the axial housing 121 is the axial groove bottom of the groove-shaped housing, the circumferential housing 122 is the circumferential groove wall of the groove-shaped housing, and the cavity enclosed by the axial housing 121 and the circumferential housing 122 is used to accommodate multiple stator cores 110. In one embodiment, multiple protrusions 111 are spaced from the circumferential housing 122 along the radial direction R of the motor 11, which is conducive to reducing the difficulty of installing the stator core 110.

[0109] In the embodiment of the present application, the distance between each groove 112 and the circumferential shell 122 along the radial direction R of the motor 11 is greater than the distance between each protrusion 111 and the circumferential shell 122, and the coolant can flow in the gap between each groove 112 and the circumferential shell 122. Among them, the groove 112a of the first stator core 110a and the groove 112a of the second stator core 110b are used to form an axial flow channel 113. Specifically, each gap of the first stator core 110a is connected with a gap of the second stator core 110b along the axial direction O of the motor 11, so that the coolant can flow back and forth on the outer peripheral surface of the first stator core 110a and the second stator core 110b, which is conducive to reducing the resistance of the coolant flowing between the first stator core 110a and the second stator core 110b, and realizing that the coolant cools the first stator core 110a and the second stator core 110b along the circumferential direction C of the motor 11. In one embodiment, the stator cores 110 other than the first stator core 110a and the second stator core 110b among the multiple stator cores 110 can also form multiple axial flow channels 113, which is beneficial to further expand the heat dissipation area of ​​the coolant and alleviate the problem of insufficient local cooling of the stator core 110.

[0110] In the embodiment of the present application, the formation of the axial flow channel 113 only involves the fixed structure and outer peripheral surface of the different stator cores 110 themselves, and no additional components are used, which is conducive to the structural reuse of the protrusion 111, and can also reduce the changes to other structures in the motor 11, which is conducive to reducing design and processing costs.

[0111] In one embodiment, the axial housing 121 and the circumferential housing 122 are integrally formed. In one embodiment, the axial housing 121 and the circumferential housing 122 are separate structures.

[0112] It should be noted that the axial flow channel 113 in the embodiment of the present application is formed based on the protrusions 111 and grooves 112 of the multiple stator cores 110, and the boundaries of the axial flow channel 113 are also divided by the protrusions 111 and grooves 112. Specifically, the axial flow channel 113 formed by the first stator core 110a and the second stator core 110b is the area between the axial projections of the adjacent protrusions 111a and 111b, and is also the area where the adjacent grooves 112a and 112b are connected. The boundaries of the axial flow channel 113 are as shown in FIG. Figure 5 shown.

[0113] Please continue reading Figure 5 In one embodiment, the length of each axial flow channel 113 along the circumferential direction C of the motor 11 is less than the length of each groove 112 in a first stator core 110a or a second stator core 110b.

[0114] In the embodiment of the present application, the axial projection of the plurality of protrusions 111a in the first stator core 110a does not overlap with the axial projection of the plurality of protrusions 111b in the second stator core 110b. Accordingly, the axial projection of the plurality of grooves 112a in the first stator core 110a does not completely overlap with the axial projection of the plurality of grooves 112b in the second stator core 110b. Each axial flow channel 113 is a connecting area of ​​the grooves 112 of different stator cores 110, so the circumferential length of each axial flow channel 113 is less than the length of each groove 112 in the first stator core 110a or the second stator core 110b. The circumferential length of the axial flow channel 113 is relatively small, which facilitates the staggered arrangement of the protrusions 111a of the first stator core 110a and the protrusions 111b of the second stator core 110b.

[0115] See also Figures 9 to 11 , Fig. 9 Another partial structural diagram of the motor 11 provided in the embodiment of the present application is shown in FIG. Fig.10 Another structural schematic diagram of the motor 11 provided in the embodiment of the present application is shown in FIG. Fig.11 Another structural schematic diagram of the stator core 110 provided in an embodiment of the present application. In one embodiment, the plurality of stator cores 110 further include a third stator core 110c, and a third stator core 110c and a first stator core 110a are arranged on both sides of a second stator core 110b along the axial direction O of the motor 11. The projection of at least one protrusion 111 in a third stator core 110c and the projection of at least one protrusion 111b in a second stator core 110b coincide with each other along the axial direction O of the motor 11.

[0116] In the embodiment of the present application, for the convenience of distinction, the protrusion 111 and the groove 112 of the third stator core 110c are respectively recorded as the protrusion 111c and the groove 112c. The third stator core 110c and the second stator core 110b are arranged adjacent to each other along the axial direction O of the motor 11, and the protrusions 111c and the protrusions 111b whose axial projections overlap in the third stator core 110c and the second stator core 110b share a fixing member 140. The axial projection of at least one protrusion 111c overlaps with the axial projection of at least one protrusion 111b, so that the axial projection of at least one groove 112c overlaps with the axial projection of at least one groove 112b, so that the coolant flowing between the first stator core 110a and the second stator core 110b can also flow to the groove 112c of the third stator core 110c through the groove 112b of the second stator core 110b.

[0117] In one embodiment, the number of protrusions 111b of a second stator core 110b is equal to the number of protrusions 111c of a third stator core 110c. Along the axial direction O of the motor 11, the projection of the plurality of protrusions 111c in a third stator core 110c coincides with the projection of the plurality of protrusions 111b in a second stator core 110b.

[0118] In the embodiment of the present application, the number of protrusions 111b of the second stator core 110b is equal to the number of protrusions 111c of the third stator core 110c, and the axial projections of the protrusions 111b of the second stator core 110b and the protrusions 111c of the third stator core 110c overlap, which is conducive to reducing the flow resistance of the coolant between the second stator core 110b and the third stator core 110c. In one embodiment, the second stator core 110b and the third stator core 110c can use the same core punching sheet 115, and the second stator core 110b and the third stator core 110c can be stacked without using a spiral stacking method during the stacking process.

[0119] In the embodiment of the present application, an axial flow channel 113 may also be formed between the second stator core 110b and the third stator core 110c, and the length of the axial flow channel 113 formed by the second stator core 110b and the third stator core 110c along the circumferential direction C of the motor 11 is equal to the length of the groove 112b or the groove 112c.

[0120] Please continue reading Figures 9 to 11In one embodiment, the plurality of stator cores 110 further include a fourth stator core 110d, and the number of protrusions 111 of the fourth stator core 110d is equal to the number of protrusions 111a of the first stator core 110a. At least two stator cores 110 are arranged between the fourth stator core 110d and the first stator core 110a along the axial direction O of the motor 11. The projection of the plurality of protrusions 111 in the fourth stator core 110d along the axial direction O of the motor 11 coincides with the projection of the plurality of protrusions 111a in the first stator core 110a. The projection of the plurality of protrusions 111 of at least one of the at least two stator cores 110 along the axial direction O of the motor 11 does not coincide with the projection of the plurality of protrusions 111a of the first stator core 110a.

[0121] In the embodiment of the present application, for the convenience of distinction, the protrusion 111 and the groove 112 of the fourth stator core 110d are respectively recorded as the protrusion 111d and the groove 112d. The axial projections of the multiple protrusions 111a of the first stator core 110a and the multiple protrusions 111d of the fourth stator core 110d overlap, and one protrusion 111a can share a fixing member 140 with one protrusion 111d. At least two other stator cores 110 are located between the first stator core 110a and the fourth stator core 110d, and the groove 112 of at least one stator core 110 in the middle position converges the coolant and then guides the coolant to the groove 112a and the groove 112d respectively. The positional relationship between the protrusions 111 of different stator cores 110 further increases the complexity of the cooling channel, which is conducive to improving the turbulence effect of the protrusion 111 on the coolant. The coolant in the groove 112 of at least one stator core 110 in the middle position is difficult to directly flow out of the stator core 110 along the axial direction O of the motor 11 , which is beneficial to improving the cooling efficiency of the stator core 110 .

[0122] In one embodiment, the stator core 110 in the middle position is a second stator core 110b and a third stator core 110c. In one embodiment, the stator core 110 in the middle position is another first stator core 110a and a second stator core 110b. In one embodiment, the stator core 110 in the middle position is a second stator core 110b and another fourth stator core 110d.

[0123] See also Fig.12 , Fig.12 Another partial structural schematic diagram of the motor 11 provided in an embodiment of the present application. In one embodiment, there may be only one stator core 110 between the first stator core 110a and the fourth stator core 110d, and the projection of the multiple protrusions 111 of the stator core 110 along the axial direction O of the motor 11 does not overlap with the projection of the protrusions 111a and 111d.

[0124] In one embodiment, the number of stator cores 110 of the motor 11 can be adjusted according to actual needs. For example, the number of stator cores 110 of the motor 11 is preferably 4 or 6.

[0125] It should be noted that since the cooling channel formed by the protrusion 111 and the groove 112 of the stator core 110 is not a completely closed channel, even if the protrusion 111d extends the movement path of the coolant, the impact on the flow resistance of the coolant can be ignored. On the contrary, the maze structure formed on the outer peripheral surface of the stator core 110 in the embodiment of the present application helps to expand the coverage of the coolant on the outer peripheral surface of the stator core 110 and alleviate the problem of insufficient local cooling.

[0126] In one embodiment, among at least two stator cores 110 located between the first stator core 110a and the fourth stator core 110d, the number of protrusions 111 of one stator core 110 is greater than the number of protrusions 111a of the first stator core 110a and the number of protrusions 111d of the fourth stator core 110d.

[0127] In the embodiment of the present application, a stator core 110 is located between the first stator core 110a and the fourth stator core 110d, and the number of protrusions 111 of a stator core 110 is different from that of protrusions 111a and protrusions 111d, so a stator core 110 must include at least one protrusion 111 to ensure that the axial projection of the protrusion 111 does not overlap with the axial projections of a protrusion 111a and a protrusion 111d. The different numbers of protrusions 111 of different stator cores 110 are beneficial to increase the complexity of the cooling flow channels on the outer peripheral surfaces of multiple stator cores 110, play a turbulent role on the coolant, and enhance the heat dissipation efficiency.

[0128] Please continue reading Figure 4 and Fig.11 In one embodiment, along the circumferential direction C of the motor 11 , the width of at least one groove 112 in each stator core 110 is greater than the width of each protrusion 111 .

[0129] In the embodiment of the present application, the circumferential length of the protrusion 111 is smaller than the circumferential length of the groove 112, which is beneficial to reduce the area occupied by the protrusion 111 on the outer circumferential surface of the stator core 110, increase the actual cooling area of ​​the coolant, and reduce the contact area between the protrusion 111 and the motor housing 120, thereby preventing the stator core 110 from wearing the motor housing 120 during installation. In the embodiment of the present application, the stator core 110 and the motor housing 120 are fixed along the axial direction O of the motor 11, rather than being interference fit along the radial direction R of the motor 11, so the relatively small circumferential length of the protrusion 111 will not have a negative impact on the connection strength between the stator core 110 and the motor housing 120.

[0130] Please continue reading Figure 3 In one embodiment, along the axial direction O of the motor 11, the width of each groove 112a in a first stator core 110a is equal to the width of each protrusion 111a in a first stator core 110a.

[0131] In the embodiment of the present application, after flowing to the protrusion 111a, the coolant can flow directly to the groove 112a along the edge of the protrusion 111a, which is beneficial to reducing the flow resistance of the coolant on the outer peripheral surface of the same stator core 110.

[0132] Please continue reading Figure 4 and Fig.11 In one embodiment, the thickness of each stator core 110 along the axial direction O of the motor 11 is smaller than the length of each protrusion 111 in each stator core 110 along the circumferential direction C of the motor 11 .

[0133] In the embodiment of the present application, the axial thickness of each stator core 110 is relatively small, which is convenient for increasing the number of stator cores 110, and the different layouts of the protrusions 111 and the grooves 112 in multiple stator cores 110 are realized by spiral stacking of the core punching sheets to meet the heat dissipation requirements of the motor 11 in different application scenarios. The circumferential length of each protrusion 111 is relatively large, which is conducive to improving the stability of the fixed connection between the stator core 110 and the motor housing 120. In one embodiment, if the total number of stator cores 110 is small, the thickness of each stator core 110 along the axial direction O of the motor 11 can be adjusted to be greater than the length of each protrusion 111 in each stator core 110 along the circumferential direction C of the motor 11, which is conducive to increasing the flow rate of the coolant in the groove 112, increasing the area connected between the grooves 112 of different stator cores 110, and enhancing the cooling efficiency.

[0134] It should be noted that Figure 5 , Figure 6 , Fig. 9 and Fig.12 Only the area of ​​the axial flow channel 113 is schematically shown, which does not represent the size relationship between each stator core 110 and the protrusions 111 and the grooves 112 .

[0135] Please continue reading Figure 4 and Fig.11In one embodiment, each stator core 110 includes a center hole 116 and a plurality of winding slots 117, and the plurality of winding slots 117 are used to accommodate the windings 130. Among them, a center hole 116 of one of the two adjacent stator cores 110 is connected to a center hole 116 of the other stator core 110 along the axial direction O of the motor 11. Each winding slot 117 of one of the two adjacent stator cores 110 is connected to a winding slot 117 of the other stator core 110 along the axial direction O of the motor 11. The width of each winding slot 117 along the circumferential direction C of the motor 11 is less than the width of a protrusion 111.

[0136] In the embodiment of the present application, the center holes 116 of two adjacently arranged stator cores 110 are connected, and the center holes 116 are used to accommodate the rotor or motor shaft of the motor 11. The winding slots 117 of the two adjacently arranged stator cores 110 are connected, and the winding slots 117 are used to accommodate the windings 130. Since the protrusions 111 can change the flow direction of the coolant, the circumferential width of the protrusions 111 is larger than the circumferential width of the winding slots 117, so that the protrusions 111 play a buffering role for the flow of the coolant, avoid a sharp change in the flow direction of the coolant, and reduce the loss of the coolant during the flow process.

[0137] Please refer to Figures 3 to 5 In one embodiment, the length of the winding 130 in each winding slot 117 along the axial direction O of the motor 11 along the axial direction O of the motor 11 is greater than the sum of the thicknesses of the plurality of stator cores 110. Each groove 112a of the first stator core 110a is adjacent to and communicates with one end surface 114 of the first stator core 110a along the axial direction O of the motor 11, and one end surface 114 of the first stator core 110a is used to transport the coolant flowing out of each groove 112a to the end of the winding 130.

[0138] In the embodiment of the present application, the end of the winding 130 along the axial direction O of the motor 11 is exposed in the winding slot 117. An end face 114 of the first stator core 110a is adjacent to and connected to each groove 112a. After the coolant flows to the groove 112a, it can continue to flow to the exposed end of the winding 130 through the end face 114 of the first stator core 110a, thereby cooling and dissipating the heat of the winding 130 and improving the utilization rate of the coolant. Among them, the coolant needs to flow through the entire groove 112a along the axial direction O of the motor 11 before it can flow to the winding 130. Therefore, the flow rate of the coolant flowing from the first stator core 110a to the winding 130 can be controlled within a relatively small range, which also makes it possible for the embodiment of the present application to not additionally install a sealing structure on the end face 114 of the first stator core 110a.

[0139] Please continue reading Figure 3 and Figure 5In one embodiment, a circumferential housing 122 includes a through hole 1221, and the through hole 1221 is used to guide the coolant in an internal flow channel 1222 of the circumferential housing 122 to a groove 112. In the axial direction O of the motor 11, a through hole 1221 is arranged alternately with a protrusion 111, and along the circumferential direction C of the motor 11, a through hole 1221 is arranged alternately with an axial flow channel 113.

[0140] In the embodiment of the present application, for ease of description, a through hole 1221 is recorded as a through hole 1221a. The coolant in the internal flow channel 1222 flows to the outer peripheral surface of the stator core 110 through the through hole 1221a. Taking the protrusion 111a as an example, the projection of the through hole 1221a along the radial direction of the motor is spaced apart from the projection 111a along the axial direction O of the motor 11, so that the through hole 1221a can directly guide the coolant to the groove 112a, and the through hole 1221a is also spaced apart from the axial flow channel 113 along the circumferential direction C of the motor 11, so that the coolant falling in the groove 112a can move directly to both sides along the circumferential direction C of the motor 11, reducing the obstruction to the coolant. In one embodiment, the powertrain also includes an oil pump, which is used to transport coolant to the internal flow channel 1222 of the circumferential housing 122 to provide power for the movement of the coolant.

[0141] Please continue reading Figure 5 In one embodiment, an opening of a through hole 1221 is from a groove 112 of one stator core 110 toward a groove 112 of another stator core 110 , and one stator core 110 is arranged adjacent to another stator core 110 along the axial direction O of the motor 11 .

[0142] In the embodiment of the present application, taking the first stator core 110a and the second stator core 110b as an example, by adjusting the opening direction of the flow hole 1221, the initial movement direction of the coolant after flowing out of the flow hole 1221 is directed from the groove 112a to the groove 112b, which is beneficial to improving the movement rate of the coolant between the protrusion 111a and the protrusion 111b.

[0143] See also Fig.13 , Fig.13 Another partial structural diagram of the motor 11 provided in an embodiment of the present application. In one embodiment, along the radial direction R of the motor 11 , the distance between a through hole 1221 and the outer peripheral surface of a stator core 110 excluding each protrusion 111 is less than the length of each protrusion 111 .

[0144] In the embodiment of the present application, the coolant flowing out of the through hole 1221a does not flow directly to the protrusion 111, but flows to the outer peripheral surface of the stator core 110 except the protrusion 111. The radial distance between the through hole 1221 and the outer peripheral surface of the stator core 110 is relatively close, which can shorten the moving distance of the coolant between the through hole 1221a and the stator core 110, which is conducive to improving the flow rate of the coolant.

[0145] Please continue reading Fig.13 . In one embodiment, a circumferential shell 122 includes an internal flow channel 1222, an internal flow channel 1222 is arranged between two protrusions 111 along the circumferential direction C of the motor 11, and an internal flow channel 1222 extends along the axial direction O of the motor 11. A through hole 1221 runs through an internal flow channel 1222, and the ratio of the inner diameter of a through hole 1221 to the inner diameter of an internal flow channel 1222 is greater than or equal to 0.1 and less than or equal to 0.3. In the embodiment of the present application, if the inner diameter of the through hole 1221 is too large, it is not conducive to forming a large flow pressure in the internal flow channel 1222, which will reduce the flow rate of the coolant and have a negative impact on the cooling efficiency.

[0146] Please continue reading Figure 3 and Fig.10 In one embodiment, a circumferential housing 122 further includes another through hole 1221, and the other through hole 1221 is used to guide part of the coolant in an internal flow channel 1222 of a circumferential housing 122 to the end of the winding 130. The projection of the other through hole 1221 along the radial direction R of the motor 11 does not overlap with the plurality of stator cores 110.

[0147] In the embodiment of the present application, for the convenience of description, the through hole 1221 used to cool the stator core 110 is recorded as the through hole 1221a, and the through hole 1221 used to cool the end of the winding 130 is recorded as the through hole 1221b. Part of the coolant flows to one end of the winding 130 through the through hole 1221b, so as to cool and dissipate the heat of the winding 130, which is beneficial to reduce the heat loss of the winding 130. In one embodiment, a circumferential shell 122 includes two through holes 1221b, and the two through holes 1221b respectively guide part of the coolant to the two ends of the winding 130. In one embodiment, the number of through holes 1221a connected to an internal flow channel 1222 is less than or equal to 3. An excessively large number of flow holes 1221a is not conducive to forming a larger flow pressure in the internal flow channel 1222. The flow resistance of the coolant in the internal flow channel 1222 is reduced, which will reduce the flow rate of the coolant flowing out of the flow holes 1221a, thereby having a negative impact on the cooling efficiency.

[0148] Please continue reading Fig.13In one embodiment, a circumferential shell 122 includes a plurality of internal flow channels 1222, and each internal flow channel 1222 is spaced apart and located between two different protrusions 111 along the circumference C of the motor 11. In the embodiment of the present application, an increase in the number of internal flow channels 1222 is beneficial to increasing the flow rate of the coolant. The plurality of internal flow channels 1222 are distributed between different protrusions 111, which can promote the flow of the coolant around the outer circumference of the stator core 110. Exemplarily, the number of internal flow channels 1222 may be an integer greater than or equal to 1. In one embodiment, part of the flow holes of each internal flow channel are used to guide the coolant to the groove, and another part of the flow holes are used to guide the coolant to the end of the winding. In another embodiment, each flow hole of a part of the internal flow channel is used to guide the coolant to the groove, and each flow hole of another part of the internal flow channel is used to guide the coolant to the end of the winding.

[0149] In one embodiment, the arc formed by the plurality of internal flow channels has an arc angle greater than or equal to 120 degrees and less than or equal to 180 degrees.

[0150] In one embodiment, the intervals between every two adjacent internal flow channels among the plurality of internal flow channels along the circumference of the motor are different from each other.

[0151] The above is a detailed introduction to the motor, powertrain and vehicle for driving the vehicle provided in the embodiments of the present application. Specific examples are used in this article 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 for driving a vehicle, 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, the plurality of stator cores are arranged adjacent to each other in the axial direction of the motor, and the outer peripheral surface of each stator core comprises a plurality of grooves and a plurality of protrusions, wherein: In each of the stator cores, the plurality of protrusions are arranged at intervals along the circumferential direction of the motor, each of the grooves is arranged between two of the protrusions along the circumferential direction of the motor, and each of the protrusions protrudes toward the inner wall of the motor housing along the radial direction of the motor; The multiple stator cores include a first stator core and a second stator core. The first stator core and the second stator core are arranged adjacent to each other along the axial direction of the motor. The projection of at least one protrusion in the first stator core does not overlap with the projection of each protrusion in the second stator core along the axial direction of the motor.

2. The motor according to claim 1, characterized in that The number of the protrusions of the first stator core is equal to the number of the protrusions of the second stator core, and the projection of the multiple protrusions in the first stator core along the axial direction of the motor does not overlap with the projection of the multiple protrusions in the second stator core.

3. The motor according to any one of claims 1 to 2, characterized in that: The multiple stator cores also include a third stator core, and the third stator core and the first stator core are arranged on both sides of the second stator core along the axial direction of the motor, and the projection of at least one protrusion in the third stator core along the axial direction of the motor coincides with the projection of at least one protrusion in the second stator core.

4. The motor according to claim 3, characterized in that The number of the protrusions of the second stator core is equal to the number of the protrusions of the third stator core, and the projection of the multiple protrusions in the third stator core along the axial direction of the motor coincides with the projection of the multiple protrusions in the second stator core.

5. The motor according to any one of claims 1 to 4, characterized in that: The multiple stator cores also include a fourth stator core, the number of protrusions of the fourth stator core is equal to the number of protrusions of the first stator core, at least two stator cores are arranged between the fourth stator core and the first stator core along the axial direction of the motor, the projection of the multiple protrusions in the fourth stator core along the axial direction of the motor coincides with the projection of the multiple protrusions in the first stator core, and the projection of the multiple protrusions of at least one of the at least two stator cores along the axial direction of the motor does not coincide with the projection of the multiple protrusions of the first stator core.

6. The motor according to claim 5, characterized in that The number of the protrusions of one of the at least two stator cores is greater than the number of the protrusions of the first stator core and the number of the protrusions of the fourth stator core.

7. The motor according to any one of claims 1 to 6, characterized in that: The width of at least one of the grooves in each of the stator cores along the circumferential direction of the motor is greater than the width of each of the protrusions.

8. The motor according to any one of claims 1 to 7, characterized in that: The width of each of the grooves in the first stator core along the axial direction of the motor is equal to the width of each of the protrusions in the first stator core.

9. The motor according to any one of claims 1 to 8, characterized in that: The thickness of each of the stator cores along the axial direction of the motor is smaller than the length of each of the protrusions in each of the stator cores along the circumferential direction of the motor.

10. The motor according to any one of claims 1 to 9, characterized in that: Each of the stator cores comprises a central hole and a plurality of winding slots, wherein the plurality of winding slots are used to accommodate windings, wherein: One of the center holes of one of the two adjacent stator cores is connected to one of the center holes of the other stator core along the axial direction of the motor, and each of the winding slots of one of the two adjacent stator cores is connected to one of the winding slots of the other stator core along the axial direction of the motor, and the width of each of the winding slots along the circumferential direction of the motor is smaller than the width of one of the protrusions.

11. The motor according to claim 10, characterized in that The motor housing includes an axial housing, and the axial housing is arranged adjacent to a stator core along the axial direction of the motor. The outer peripheral surface of each stator core includes a plurality of through holes, and each through hole penetrates a protrusion along the axial direction of the motor. The axial housing is used to fix and connect a plurality of fixing parts, and each fixing part is used to pass through at least one through hole along the axial direction of the motor. The length of the winding in each winding slot along the axial direction of the motor is greater than the sum of the thicknesses of the plurality of stator cores.

12. The motor according to any one of claims 1 to 11, characterized in that: The motor housing includes a circumferential shell, which surrounds the outer circumferential surface of the multiple stator cores. Each of the grooves in each of the stator cores forms a gap with the circumferential shell. Each of the gaps in the first stator core is used to connect with a gap in the second stator core along the axial direction of the motor to form an axial flow channel.

13. The motor according to claim 12, characterized in that The length of each of the axial flow channels along the circumferential direction of the motor is smaller than the length of each of the grooves in the first stator core or the second stator core.

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 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.

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