Oil cooling motor, power assembly and electric vehicle

Abstract

The invention provides an oil-cooled motor, a power assembly and an electric vehicle, a stator of the oil-cooled motor comprises a first iron core and two second iron cores, and the first iron core is stacked and arranged between the two second iron cores along the axial direction of the stator. At least two groups of first through holes of the first iron core are arranged in a staggered manner along the axial direction of the stator, each group of first through holes comprises a plurality of first through holes which are arranged at intervals along the circumferential direction of the stator, and a gap of the first iron core is used for receiving cooling liquid output by the shell and conveying the cooling liquid to two adjacent first through holes in the other group of first through holes adjacent to one group of first through holes; each second through hole of the first iron core is arranged between the first through hole and the axis of the stator at intervals along the radial direction of the stator, each second iron core comprises a plurality of groups of third through holes which are arranged at intervals along the circumferential direction of the stator, and each of a part of third through holes in each group of third through holes is used for communicating one first through hole and one second through hole. According to the scheme, cooling liquid can be prevented from leaking from the welding seam of the iron core while double-layer flow channel heat dissipation is achieved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of electric vehicles, in particular to an oil-cooled motor, a power assembly and an electric vehicle. BACKGROUND

[0002] With the development of electric vehicles, the demand for high-speed and high-density, lightweight and miniaturization of motors in the power assembly is increasing, which brings huge heat dissipation challenges. Motor over-temperature can cause insulation failure and demagnetization of permanent magnets embedded in the rotor, and thus the power assembly cannot work normally, affecting driving safety. Therefore, it is necessary to cool the stator by oil to solve the problem of stator cooling. When oil is passed through the outer circumferential surface of the stator core, the oil flows through the weld seam of the welded core, which is easy to cause oil leakage at the weld seam position, so that the amount of oil participating in the cooling of the stator becomes smaller, resulting in poor motor heat dissipation effect. SUMMARY

[0003] The present application provides an oil-cooled motor, a power assembly and an electric vehicle to prevent cooling liquid from leaking from the weld seam of the stator core and improve the cooling effect of the stator.

[0004] In a first aspect, the present application provides an oil-cooled motor, a power assembly and an electric vehicle to prevent cooling liquid from leaking from the weld seam of the stator core and improve the cooling effect of the stator.

[0005] In the embodiments of the present application, the at least two groups of first through holes are arranged in a staggered manner along the axial direction of the stator, and each group of first through holes includes a plurality of first through holes arranged in a spaced manner along the circumferential direction of the stator, so that the first through holes in the at least two groups of first through holes can be communicated along the axial direction of the stator.

[0006] In the embodiment of the present application, the notch of the first core is arranged between two adjacent first through holes in a group of first through holes along the circumferential direction of the stator, and the opening direction of the notch is away from the axis of the stator along the radial direction of the stator. The notch is used for receiving the cooling liquid output by the shell and conveying it to two adjacent first through holes in another group of first through holes adjacent to the group of first through holes, so that the notch can input the cooling liquid received from the shell into the first through hole of the first core, and the cooling liquid flows inside the first core of the stator, so that the cooling liquid does not need to flow through the welding seam on the outer circumferential surface of the stator core, preventing the leakage of the cooling liquid, increasing the amount of cooling liquid effectively participating in the cooling of the stator in the first core of the stator, and ensuring the cooling effect of the stator. Also, the shell does not need to be provided with a flow distribution groove to achieve the axial flow and circumferential flow of the cooling liquid in the first core of the stator.

[0007] In the embodiment of the present application, each of a part of the third through holes in each group of the third through holes of the second core is used for communicating one first through hole and one second through hole, so that the cooling liquid in the first through hole of the first core can be input into the second through hole through a part of the third through holes of the second core, and each second through hole is arranged between the first through hole and the axis of the stator along the radial direction of the stator, so that the first core of the stator has double-layer cooling liquid flow channels in the radial direction of the stator, thereby facilitating the increase of the heat dissipation area of the cooling liquid and the first core of the stator, and facilitating the improvement of the cooling effect of the stator. In addition, the second through hole can be closer to the stator winding fixed by the first core of the stator, and it is more convenient to quickly dissipate the large amount of heat generated by the stator winding through the cooling liquid in the second through hole.

[0008] In the embodiment of the present application, each of another part of the third through holes in each group of the third through holes is communicated with another second through hole and not communicated with the first through hole, so that another part of the third through holes of each second core does not directly receive the cooling liquid output from the first through hole, and each of another part of the third through holes in one second core can receive the cooling liquid in the first through hole conveyed by a part of the third through holes of another second core through another second through hole, so that the flow path of the cooling liquid in the stator is longer, and the heat dissipation of the stator is more uniform.

[0009] In the embodiment of the present application, each second core includes a plurality of groups of third through holes, and the plurality of groups of third through holes are arranged along the circumferential direction of the stator. Each of a part of the third through holes in each group of the third through holes is used for communicating one first through hole and one second through hole, and each of another part of the third through holes in each group of the third through holes is communicated with another second through hole and not communicated with the first through hole. Thus, the cooling liquid has multiple double-layer cooling liquid flow channels inside the stator core, and the flow directions of the cooling liquid in two adjacent double-layer cooling liquid flow channels along the circumferential direction of the stator are opposite, thereby facilitating the more uniform heat dissipation of the cooling liquid to the stator and improving the cooling effect of the stator.

[0010] In the embodiment of the present application, the first core is arranged in the gap between the two adjacent first through holes in the first group of through holes to receive the cooling liquid input by the shell, and the cooling liquid in the gap is transported into the two first through holes in the other group of first through holes adjacent to the gap in the axial direction of the stator to achieve staggered communication, thereby achieving the circumferential flow and axial flow of the cooling liquid in the stator, so that the flow distribution channel does not need to be arranged on the shell, and the leakage of the cooling liquid is prevented. The flow of the cooling liquid on the outer circumferential surface of the stator is avoided, thereby preventing the leakage of the cooling liquid from the welding seam of the stator core, increasing the amount of cooling liquid effectively participating in the cooling of the stator, and facilitating the improvement of the cooling effect of the stator. The third through hole of the second core is communicated with the first through hole and the second through hole, so that a double-layer cooling liquid flow channel can be formed in the stator core, and the cooling effect of the stator is improved.

[0011] In an embodiment, the shell includes a shell liquid inlet hole, which is aligned with the gap of the first core in the radial direction of the stator, so that the cooling liquid input by the shell liquid inlet hole can enter the gap of the first core in the shortest path, and then be transported into the first through hole through the gap, thereby facilitating the improvement of the cooling effect of the stator.

[0012] In an embodiment, in the axial direction of the stator, one first through hole in the first group of through holes is used to communicate with the two adjacent first through holes in the other group of first through holes. In the circumferential direction of the stator, the circumferential length of each first through hole is greater than the distance between the two adjacent first through holes in each group of first through holes.

[0013] In the embodiment of the present application, one first through hole in the first group of through holes is used to communicate with the two adjacent first through holes in the other group of first through holes, so that at least two groups of first through holes in the first core can be axially communicated, and the cooling liquid can flow axially and circumferentially in the at least two groups of first through holes of the first core.

[0014] In the embodiment of the present application, in the circumferential direction of the stator, the circumferential length of each first through hole is greater than the distance between the two adjacent first through holes in each group of first through holes, so that after the at least two groups of first through holes are arranged in a staggered manner in the axial direction of the stator, the first through hole in one group of first through holes is not blocked by the core part between the two adjacent first through holes in the other group of first through holes, thereby facilitating the axial communication and circumferential communication between the at least two groups of first through holes, and the cooling liquid can flow axially and circumferentially in the at least two groups of first through holes of the first core.

[0015] In an embodiment, in the circumferential direction of the stator, the distance between the gap and any one of the two adjacent first through holes in the first group of through holes is equal to the distance between any other two adjacent first through holes in the first group of through holes. In the circumferential direction of the stator, the length of the gap is equal to the length of the first through hole.

[0016] In the embodiment of the present application, along the circumferential direction of the stator, the distance between the gap and any one of the adjacent two first through holes in the first group of through holes is equal to the distance between any other two adjacent first through holes in the first group of through holes, so that the core part between the gap and the first through hole in the first group of through holes does not affect the communication between the first through hole in the first group of through holes and the first through hole in the other group of through holes.

[0017] In the embodiment of the present application, along the circumferential direction of the stator, the length of the gap is equal to the length of the first through hole, so that the arrangement of the gap and the first through hole in the first core is more regular.

[0018] In an embodiment, the length of each first through hole along the circumferential direction of the stator is greater than the length of each first through hole along the radial direction of the stator.

[0019] In the embodiment of the present application, the length of each first through hole along the circumferential direction of the stator is greater than the length of each first through hole along the radial direction of the stator, so that the first through hole is in the shape of a circular arc, which is conducive to the axial flow and circumferential flow of a small amount of cooling liquid, and the first through hole is filled more quickly, which is conducive to improving the cooling efficiency of the stator. The length of each first through hole along the circumferential direction of the stator is greater, which also facilitates the axial communication between the first through holes in different groups of first through holes, and also makes it possible to arrange a smaller number of first through holes along the circumferential direction of the stator to achieve axial communication, and the structure is simpler.

[0020] In an embodiment, the first core includes at least two groups of first laminations stacked along the axial direction of the stator, each group of first laminations includes a plurality of first laminations stacked along the axial direction of the stator, each first lamination includes a plurality of first sub-through holes and a plurality of second sub-through holes, each first sub-through hole penetrates the first lamination along the axial direction of the first lamination, and the plurality of first sub-through holes are arranged at intervals along the circumferential direction of the first lamination, each second sub-through hole penetrates the first lamination along the axial direction of the first lamination, and the plurality of second sub-through holes are arranged at intervals along the circumferential direction of the first lamination. Each group of first laminations is arranged in a staggered manner along the circumferential direction of the stator, and the plurality of first sub-through holes of each first lamination in a group of first laminations are respectively aligned one-to-one along the axial direction of the stator to communicate with the plurality of first sub-through holes of the adjacent other first lamination to form a first group of through holes, and the plurality of first sub-through holes of each first lamination in another group of first laminations are respectively aligned one-to-one along the axial direction of the stator to communicate with the plurality of first sub-through holes of the adjacent other first lamination to form another first group of through holes. The plurality of second sub-through holes of each first lamination in the at least two groups of first laminations are respectively aligned one-to-one along the axial direction of the stator to communicate with the plurality of second sub-through holes of the adjacent other first lamination to form a plurality of second through holes.

[0021] In an embodiment, the outer circumferential surface of each first punching piece comprises an opening, the opening direction of the opening is away from the center hole of the first punching piece along the radial direction of the stator, the openings in at least some of the first punching pieces in the group of first punching pieces are aligned and communicated along the axial direction of the stator to form a gap of the first iron core for receiving the cooling liquid input by the shell.

[0022] In an embodiment, along the circumferential direction of the stator, the maximum length of each third through hole in the second iron core is smaller than the length of the iron core part between two adjacent first through holes in each group of first through holes.

[0023] In an embodiment, along the circumferential direction of the stator, the maximum length of each third through hole in the second iron core is smaller than the length of the iron core part between two adjacent first through holes in each group of first through holes, and the smaller maximum length of each third through hole in the second iron core makes another part of the third through holes in each group of third through holes in the second iron core not directly communicated with the first through holes, so that the another part of the third through holes can be used to receive the cooling liquid delivered by the opposite second iron core, the flow path of the cooling liquid in the stator iron core is longer, the heat dissipation of the cooling liquid to the stator is more uniform, and the cooling effect is improved.

[0024] In an embodiment, along the circumferential direction of the stator, the sum of the maximum lengths of three adjacent third through holes in the second iron core is smaller than the length of the first through hole, so that one first through hole can simultaneously communicate two third through holes in a part of the third through holes in the second iron core.

[0025] In an embodiment, the length of each third through hole along the radial direction of the stator is greater than the length of the third through hole along the circumferential direction of the stator. Along the radial direction of the stator, the length of each third through hole is greater than the distance between a first through hole and a second through hole.

[0026] In an embodiment, the length of each third through hole along the radial direction of the stator is greater than the length of the third through hole along the circumferential direction of the stator, and the greater length of each third through hole along the radial direction of the stator facilitates the communication between the first through hole and the second through hole for a part of the third through holes in the second iron core, so that the stator iron core has a double-layer cooling flow channel, and the cooling liquid can better dissipate heat to the stator winding, which is beneficial to improve the cooling effect of the stator.

[0027] In an embodiment, along the radial direction of the stator, the length of each third through hole is greater than the distance between a first through hole and a second through hole, and the greater length of each third through hole facilitates a part of the third through holes in each group of third through holes in the second iron core to deliver the cooling liquid in the first through hole to the second through hole along the radial direction of the stator, so that the stator iron core has a double-layer cooling flow channel, and the cooling liquid can better dissipate heat to the stator winding, which is beneficial to improve the cooling effect of the stator.

[0028] In an embodiment, the third through hole comprises two ends arranged in diametrically opposite directions along the stator, one end of the third through hole is used for communicating with one first through hole, and the other end of the third through hole is used for communicating with one second through hole. Wherein, along the circumferential direction of the stator, the length of one end is greater than the length of the other end.

[0029] In the embodiment of the present application, along the circumferential direction of the stator, the length of one end is greater than the length of the other end, and the decrease of the circumferential length from one end to the other end of the third through hole can make the flow rate of the cooling liquid flowing from one end to the other end faster. The one end of the third through hole communicating with the first through hole is larger, facilitating the one end to receive the cooling liquid of the first through hole. The other end of the third through hole communicating with the second through hole is smaller, facilitating the other end to deliver the cooling liquid with a faster flow rate to the second through hole, which is conducive to realizing the communication between the first through hole and the second through hole through the third through hole, and the faster flow rate of the cooling liquid is also more conducive to improving the cooling efficiency of the stator.

[0030] In an embodiment, the two second cores are arranged in reverse along the axial direction of the stator. Wherein, along the axial direction of the stator, a part of the third through holes in the plurality of groups of third through holes of one second core are aligned with another part of the third through holes in the plurality of groups of third through holes of the other second core. Along the axial direction of the stator, at least one third through hole in at least one group of third through holes of one second core is not aligned with any one of the plurality of groups of third through holes of the other second core.

[0031] In the embodiment of the present application, along the axial direction of the stator, a part of the third through holes in the plurality of groups of third through holes of one second core are aligned with another part of the third through holes in the plurality of groups of third through holes of the other second core. Thus, a part of the third through holes in the plurality of groups of third through holes of one second core can receive the cooling liquid from the first through hole and deliver the cooling liquid to another part of the third through holes in the plurality of groups of third through holes of the other second core through the second through hole, so that the cooling liquid can be delivered from one second core to the other second core, realizing oil delivery on both sides, making the flow path of the cooling liquid in the stator core longer, thereby reducing the large flow rate difference caused by the large difference in the flow path length of the cooling liquid in the stator core, balancing the flow rate of the cooling liquid in the stator core, which is conducive to making the heat dissipation of the cooling liquid to the stator more uniform, improving the heat dissipation effect of the stator, and ensuring the normal operation of the oil-cooled motor.

[0032] In the embodiment of the present application, at least one third through hole in at least one group of third through holes of one second core is not aligned with any one of the plurality of groups of third through holes of the other second core, so that the cooling path of the cooling liquid in the stator core is more diverse.

[0033] In an embodiment, each second core comprises a plurality of laminations stacked along an axial direction of the stator, a portion of each lamination comprises a plurality of third sub-holes penetrating through the lamination along an axial direction of the lamination, the plurality of third sub-holes are arranged in a plurality of groups along a circumferential direction of the lamination, and one lamination is arranged adjacent to another lamination. In this embodiment, along the axial direction of the stator, the plurality of third sub-holes of one lamination are aligned one-to-one with the plurality of third sub-holes of another lamination to form a plurality of third holes of the second core.

[0034] In an embodiment, a portion of each lamination comprises a plurality of third sub-holes penetrating through the lamination along an axial direction of the lamination, so that the plurality of third sub-holes of two adjacent laminations can be communicated along the axial direction of the stator.

[0035] In an embodiment, one lamination is arranged adjacent to another lamination, along the axial direction of the stator, the plurality of third sub-holes of one lamination are aligned one-to-one with the plurality of third sub-holes of another lamination to form a plurality of third holes of the second core, and the plurality of third holes are directly formed by superimposing the plurality of third sub-holes of the plurality of laminations, which is conducive to reducing the assembly complexity of the stator core, simplifying the structure of the stator, and reducing the production cost.

[0036] In an embodiment, another portion of the plurality of laminations comprises a plurality of fourth holes, one lamination is arranged adjacent to another lamination, and along the axial direction of the stator, the plurality of fourth holes of one lamination are aligned one-to-one with the plurality of fourth holes of another lamination.

[0037] In an embodiment, each of a portion of the plurality of third holes of each second core is communicated with one first hole of a group of first holes close to the second core, and each of another portion of the plurality of third holes is arranged in a spaced manner along a circumferential direction of the stator between two adjacent first holes, so that a portion of the plurality of third holes of the second core can directly receive the cooling liquid output by the first holes, and another portion of the first holes can only receive the cooling liquid delivered by the second core through the second holes from the opposite side, so that the stator core can realize oil delivery and oil injection on the opposite side, improve the balance of heat dissipation, and improve the cooling effect.

[0038] In an embodiment, each second core comprises two groups of laminations stacked along an axial direction of the stator, each group of laminations comprises a plurality of laminations stacked along the axial direction of the stator, a portion of each lamination comprises a plurality of third sub-holes, each third sub-hole penetrates the lamination along an axial direction of the lamination, the plurality of third sub-holes are arranged in a circumferential direction of the lamination in a spaced-apart manner, the plurality of third sub-holes of one group of laminations are arranged in a spaced-apart manner along a circumferential direction of the stator in sequence with the plurality of third sub-holes of the other group of laminations, and one group of laminations is arranged adjacent to the first core. The plurality of third sub-holes of each lamination in one group of laminations are aligned along the axial direction of the stator in a one-to-one manner to communicate with the plurality of third sub-holes of an adjacent lamination to form a portion of third holes of the second core. The plurality of third sub-holes of each lamination in the other group of laminations are aligned along the axial direction of the stator in a one-to-one manner to communicate with the plurality of third sub-holes of an adjacent lamination to form another portion of third holes of the second core.

[0039] In the embodiment, the plurality of third sub-holes of one group of laminations are arranged in a spaced-apart manner along the circumferential direction of the stator in sequence with the plurality of third sub-holes of the other group of laminations, so that the plurality of third sub-holes between the two groups of laminations are not communicated along the axial direction of the stator, facilitating formation of the portion of third holes and the other portion of third holes of the second core through the plurality of third sub-holes of the two groups of laminations, respectively.

[0040] In the embodiment, the plurality of third sub-holes of each lamination in one group of laminations are aligned along the axial direction of the stator in a one-to-one manner to communicate with the plurality of third sub-holes of an adjacent lamination to form the portion of third holes of the second core, and the portion of third holes of the second core is directly formed by superposition of the plurality of third sub-holes in one group of laminations, which is conducive to reducing assembly complexity, simplifying the structure of the stator, and reducing production cost.

[0041] In the embodiment, the plurality of third sub-holes of each lamination in the other group of laminations are aligned along the axial direction of the stator in a one-to-one manner to communicate with the plurality of third sub-holes of an adjacent lamination to form the other portion of third holes of the second core, and the other portion of third holes of the second core is directly formed by superposition of the plurality of third sub-holes in the other group of laminations, which is conducive to reducing assembly complexity, simplifying the structure of the stator, and reducing production cost.

[0042] In an embodiment, another portion of each lamination comprises a plurality of fourth holes, the other portion of each lamination is arranged adjacent to the portion of the lamination along a circumferential direction of the stator, the plurality of fourth holes are arranged in a spaced-apart manner along the circumferential direction of the lamination, each fourth hole is used to communicate the plurality of second holes, and at least one fourth hole is further used to communicate one first hole. Along the circumferential direction of the stator, the length of the fourth hole is greater than or equal to the interval between the adjacent at least two second holes. Along the radial direction of the stator, the length of the at least one fourth hole is greater than the interval between the first hole and the second hole.

[0043] In the embodiment of the present application, the second through hole located at the bottom of the stator after assembly often receives cooling liquid with low flow rate or almost no cooling liquid, which affects the cooling effect of the stator. A fourth through hole is arranged at another part of each lamination of the second core, each fourth through hole is used to communicate a plurality of second through holes, and at least one fourth through hole is also used to communicate a first through hole, so that the fourth through hole can directly receive the cooling liquid conveyed by the first through hole of the first core and conveyed into the plurality of second through holes at the bottom of the stator, so that the cooling liquid with high flow rate in the first through hole can flow through the plurality of second through holes at the bottom of the stator, so that the inside of the stator core at the bottom of the stator can also have more cooling liquid for cooling and temperature reduction, which is beneficial to improve the cooling effect of the stator.

[0044] In the embodiment of the present application, along the circumferential direction of the stator, the length of the fourth through hole is greater than or equal to the interval between the adjacent at least two second through holes, so that the fourth through hole can simultaneously communicate at least two second through holes, which is beneficial to the fourth through hole to simultaneously input cooling liquid into a plurality of second through holes, or to make the fourth through hole simultaneously receive the cooling liquid input from a plurality of second through holes, so that the cooperation of the fourth through hole between the two second cores can realize the series connection and parallel connection of the plurality of second through holes at the bottom, which is beneficial to improve the cooling effect of the stator.

[0045] In the embodiment of the present application, along the radial direction of the stator, the length of at least one fourth through hole is greater than the interval between one first through hole and one second through hole, so that at least one fourth through hole can be used to directly receive the cooling liquid in the first through hole of the first core, so that the cooling liquid with high flow rate can be directly conveyed from the first through hole to the second through hole at the bottom of the stator, so that the cooling effect at the bottom of the stator is better, thereby being beneficial to improve the cooling effect of the stator.

[0046] In one embodiment, the plurality of fourth through holes of the two groups of laminations of each second core are arranged in a staggered manner along the circumferential direction of the stator, and the plurality of fourth through holes in one group of laminations are communicated with the plurality of fourth through holes in the other group of laminations along the axial direction of the stator.

[0047] In one embodiment, the plurality of fourth through holes of one second core are aligned with the plurality of fourth through holes of another second core along the circumferential direction of the stator. Along the circumferential direction of the stator, one fourth through hole in one second core is arranged adjacent to one third through hole in another part of the third through hole in another second core, and the one fourth through hole is used to communicate the one third through hole in the another part of the third through hole through the second through hole.

[0048] In the embodiment of the present application, the fourth through holes of one second core are misaligned and aligned with the fourth through holes of another second core along the circumferential direction of the stator, so that the fourth through holes of the two second cores can be communicated through the second through holes, so that the series and parallel communication of the second through holes at the bottom of the stator can be realized through the cooperation of the fourth through holes between the two second cores, so that the cooling liquid can flow through most of the second through holes at the bottom of the stator, which is beneficial to improve the cooling effect of the stator.

[0049] In the embodiment of the present application, along the circumferential direction of the stator, one fourth through hole in one second core is arranged adjacent to one third through hole in another part of the third through holes in another second core, and the fourth through hole is used to communicate one third through hole in another part of the third through holes through the second through hole, so that the cooling liquid from the first through hole transported by the fourth through hole received by the second through hole at the bottom can be input into one third through hole in another part of the third through holes, thereby providing cooling liquid for one third through hole in another part of the third through holes.

[0050] In one embodiment, the stator further comprises two third cores, one third core is arranged on the side away from the first core of one second core along the axial direction of the stator, and the other third core is arranged on the side away from the first core of the other second core along the axial direction of the stator, each third core comprises a plurality of fifth through holes, the end winding of the stator is exposed to the plurality of fifth through holes, and the plurality of fifth through holes are arranged at intervals along the circumferential direction of the stator. Wherein, along the axial direction of the stator, each third through hole in another part of the third through holes in each second core is used to communicate one fifth through hole.

[0051] In the embodiment of the present application, each third core comprises a plurality of fifth through holes, and the end winding of the stator is exposed to the plurality of fifth through holes, so that the cooling liquid sprayed from the fifth through holes can be sprayed to the end winding to cool the end winding.

[0052] In the embodiment of the present application, along the axial direction of the stator, each third through hole in another part of the third through holes in each second core is used to communicate one fifth through hole, so that the cooling liquid received by each third through hole in another part of the third through holes in each second core can be sprayed from the fifth through hole. Since the cooling liquid sprayed from the plurality of fifth through holes of each third core is from the second core on the opposite side, the flow rate of the cooling liquid in the plurality of fifth through holes of each third core is equivalent, so that the heat dissipation effect of the cooling liquid sprayed from the plurality of fifth through holes is equivalent, so that the end winding is cooled more evenly, which is beneficial to prevent local hot spots of the end winding and improve the cooling effect of the stator.

[0053] In an embodiment, the axis direction of each fifth through hole in the third core intersects with the axial direction of the stator, and the axis direction of the fifth through hole is deflected towards the axis of the stator, so that the fifth through hole can perform centripetal oil injection on the end portion winding, which is conducive to improving the cooling effect of the end portion winding.

[0054] In another embodiment, the axis of each fifth through hole in the third core is the same as the axial direction of the stator, so that the fifth through hole can perform parallel oil injection on the end portion winding, which is conducive to improving the cooling effect of the end portion winding.

[0055] In an embodiment, each third core includes a plurality of third laminations stacked along the axial direction of the stator, the plurality of third laminations are rotationally stacked along the axial direction of the stator, each third lamination includes a plurality of fifth sub-through holes, each fifth sub-through hole penetrates the third lamination along the axial direction of the third lamination, the plurality of fifth sub-through holes are arranged in intervals along the circumferential direction of the third lamination, and one third lamination is arranged adjacent to another third lamination. Wherein, along the axial direction of the stator, the plurality of fifth sub-through holes of one third lamination are used to communicate with the plurality of fifth sub-through holes of another third lamination to form a plurality of fifth through holes of the third core.

[0056] In a second aspect, the application provides a power assembly, which includes a reducer and an oil-cooled motor as in the first aspect, and the motor shaft of the oil-cooled motor is drivingly connected to the input shaft of the reducer.

[0057] In the oil-cooled motor in the embodiments of the application, the gap of the first core receives the cooling liquid input by the shell, and the cooling liquid in the gap is transported into two first through holes in another group of first through holes adjacent to the gap in the axial direction to realize staggered communication, so as to realize the circumferential flow and axial flow of the cooling liquid in the stator, thereby not needing to set a flow equalizing groove on the shell to prevent the leakage of the cooling liquid. The cooling liquid is prevented from flowing on the outer circumferential surface of the stator core, thereby preventing the cooling liquid from leaking from the weld of the stator core, and the amount of the cooling liquid effectively participating in the cooling of the stator is large, which is conducive to improving the cooling effect of the stator. A part of the third through holes of the second core are communicated with the first through holes and the second through holes, and the cooling liquid in the first through holes is transported to the second through holes, so that a double-layer cooling liquid flow channel can be formed inside the stator core, which is conducive to improving the cooling effect of the stator, thereby improving the cooling effect of the oil-cooled motor and the power assembly.

[0058] In a third aspect, the application provides an electric vehicle, which includes a vehicle frame and a power assembly as in the second aspect, and the power assembly is used to receive the electric energy provided by a power battery to drive the wheels.

[0059] The power assembly in the embodiment of the present application comprises an oil-cooled motor, the oil-cooled motor receives the cooling liquid input by the shell through the gap of the first core, and the cooling liquid in the gap is delivered into two first through holes in another group of first through holes adjacent to the gap in the axial direction to realize staggered communication, so as to realize the circumferential flow and axial flow of the cooling liquid in the stator, thereby not needing to set a flow equalizing groove on the shell and preventing the leakage of the cooling liquid. The flow of the cooling liquid on the outer circumferential surface of the stator core is avoided, thereby preventing the leakage of the cooling liquid from the weld of the stator core, increasing the amount of the cooling liquid effectively participating in the cooling of the stator, and being beneficial to improving the cooling effect of the stator. The first through holes and the second through holes are communicated through a part of the third through holes of the second core, the cooling liquid in the first through holes is delivered into the second through holes, so that a double-layer cooling liquid flow channel can be formed inside the stator core, which is beneficial to improving the cooling effect of the stator, thereby improving the cooling effect of the oil-cooled motor and the power assembly, and improving the performance of the whole vehicle. BRIEF DESCRIPTION OF DRAWINGS

[0060] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed to be used in the embodiments of the present application will be described below.

[0061] Figure 1 is a schematic view of an electric vehicle provided by the embodiment of the present application;

[0062] Figure 2 is a schematic view of a power assembly provided by the embodiment of the present application;

[0063] Figure 3 is a schematic view of an oil-cooled motor provided by the embodiment of the present application;

[0064] Figure 4 is an exploded schematic view of a stator provided by the embodiment of the present application;

[0065] Figure 5 is an exploded schematic view of a first core provided by the embodiment of the present application;

[0066] Figure 6 is an exploded schematic view of a second core provided by the embodiment of the present application;

[0067] Figure 7 is a flow path schematic view of the cooling liquid provided by the embodiment of the present application;

[0068] Figure 8 is a schematic view of a stator provided by the embodiment of the present application;

[0069] Figure 9 is Figure 8 a sectional view of the stator in along A-A in

[0070] Figure 10 is Figure 8A cross-sectional view of the stator along B-B in FIG. 1;

[0071] Figure 11 FIG. 1 is a schematic diagram of a first iron core according to an embodiment of the present application;

[0072] Figure 12 FIG. 2 is a schematic diagram of a second iron core according to an embodiment of the present application;

[0073] Figure 13 FIG. 3 is a comparison diagram of the flow rate of oil injection for end winding oil injection according to the scheme of the present application and the scheme of single-layer oil channel;

[0074] Figure 14 FIG. 4 is an exploded schematic diagram of a stator according to another embodiment of the present application;

[0075] Figure 15 FIG. 5 is a schematic diagram of a second iron core according to another embodiment of the present application;

[0076] Figure 16 FIG. 6 is a schematic diagram of a stator and a cooling liquid flow path according to another embodiment of the present application;

[0077] Figure 17 FIG. 7 is a cross-sectional view of a stator according to another embodiment of the present application;

[0078] Figure 18 FIG. 8 is another cross-sectional view of a stator according to another embodiment of the present application. DETAILED DESCRIPTION

[0079] The technical solutions in the embodiments of the present application will be described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only some of the embodiments of the present application, not all the embodiments.

[0080] For the convenience of understanding, the English abbreviations and related technical terms involved in the embodiments of the present application will be explained and described below.

[0081] This application provides an oil-cooled motor. The housing of the oil-cooled motor is used to accommodate and fix the stator of the oil-cooled motor. The stator includes a first iron core and two second iron cores. The first iron cores are stacked between the two second iron cores along the axial direction of the stator. The first iron core includes at least two sets of first through holes, a plurality of second through holes, and a notch. The at least two sets of first through holes are staggered along the axial direction of the stator. Each set of first through holes includes a plurality of first through holes spaced apart along the circumference of the stator. The notch is spaced apart along the circumference of the stator between two adjacent first through holes in one set of first through holes. The opening direction of the notch is radially away from the axis of the stator. The notch is used to receive coolant output from the housing and deliver it to two adjacent first through holes in another set of first through holes adjacent to the first set of first through holes. Each second through hole is spaced apart radially between the first through hole and the axis of the stator. The plurality of second through holes are spaced apart along the circumference of the stator. Each second core includes multiple sets of third through holes, which are arranged at intervals along the circumference of the stator. Each of the third through holes in a portion of each set is used to connect a first through hole and a second through hole, while each of the third through holes in another portion of each set is connected to another second through hole but not to a first through hole.

[0082] The coolant input from the housing is received through a notch in the first iron core, and the coolant from the notch is delivered to two first through holes in another set of first through holes adjacent to it along the axial direction, achieving staggered communication. This allows for both circumferential and axial flow of coolant in the stator, eliminating the need for flow equalization grooves on the housing and preventing coolant leakage. Coolant flow on the outer circumferential surface of the stator core is prevented, thus preventing leakage from the stator core welds and ensuring a large effective volume of coolant for stator cooling, which improves the stator cooling effect. A portion of the third through hole in the second iron core connects to the first and second through holes, delivering coolant from the first through hole to the second through hole, thereby forming a double-layer coolant flow channel inside the stator core, further enhancing the stator cooling effect.

[0083] The oil-cooled motor provided in this application embodiment is applied to the powertrain, which is then applied to an electric vehicle to improve the overall performance of the electric vehicle.

[0084] Figure 1 This is a schematic diagram of an electric vehicle 1 provided in an embodiment of this application.

[0085] In one embodiment, the electric vehicle 1 includes a frame 10, a powertrain 20, a power battery 30, and wheels 40. Wherein, as... Figure 1 As shown, the powertrain 20 and the power battery 30 are fixed to the frame 10. The powertrain 20 receives power from the power battery 30 and drives the wheels 40. In this embodiment, the electric vehicle 1 refers to a wheeled device driven or towed by a power unit.

[0086] Figure 2 is a schematic diagram of a power assembly 20 provided by an embodiment of the present application, Figure 3 is a schematic diagram of an oil-cooled motor 21 provided by an embodiment of the present application, Figure 4 is an exploded schematic diagram of a stator 200 provided by an embodiment of the present application.

[0087] In an embodiment, as shown in Figure 2 and Figure 3 , the power assembly 20 comprises the motor 21 and a speed reducer 22. The motor 21 comprises a housing 100, a motor shaft (not shown), the stator 200 and a rotor (not shown). The housing 100 is used to accommodate and fix the stator 200. The rotor is fixedly sleeved on the motor shaft. The stator 200 drives the rotor to rotate after receiving alternating current, thereby driving the motor shaft to rotate. The speed reducer 22 comprises a gear assembly (not shown), an input shaft (not shown) and an output shaft (not shown). The input shaft receives power transmitted by the motor shaft of the motor 21 and transmits the power to the output shaft through the gear assembly. The output shaft is drivingly connected to the axle of the wheel 40 to drive the wheel 40 to rotate. In the embodiment of the present application, the stator 200 is cooled by the cooling liquid input through the housing 100 to avoid failure of the motor 21 due to overheating. The motor 21 in the embodiment of the present application can also be referred to as the oil-cooled motor 21.

[0088] In an embodiment, as shown in Figure 3 and Figure 4 , the stator 200 comprises a stator core 200a and a stator winding 200b. The stator winding 200b is fixed in the winding slot of the stator core 200a. The stator core 200a comprises a first core 210, two second cores 220 and two third cores 230. Among them, Figure 3 the stator winding 200b in the above figure only represents the schematic position of the stator winding 200b and does not represent the specific structure.

[0089] In an embodiment, the power assembly 20 further comprises a motor controller 23, as shown in Figure 1 and Figure 2 , the motor controller 23 is used to receive direct current transmitted by the power battery 30 and convert the direct current into alternating current to transmit to the motor 21 to drive the motor 21 to operate.

[0090] A large amount of heat is generated during the operation of the motor, and cooling liquid needs to be input to the stator for cooling. Double-layer flow channels are arranged on the stator core to realize side oil feeding and oil spraying. One of the layers is arranged in the stator core, and the other layer is arranged on the outer circumferential surface of the stator core. A flow equalizing groove is arranged on the motor housing to deliver cooling liquid to the other layer of the flow channel on the outer circumferential surface of the stator core. The cooling liquid flows circumferentially in the flow equalizing groove on the outer circumferential surface of the stator core. The cooling liquid flows axially in the other layer of the flow channel on the outer circumferential surface of the stator core. The cooling liquid flowing through the weld seam of the welded stator core causes oil leakage, which affects the cooling effect of the stator.

[0091] The double-layer flow channels of the stator core are arranged in the stator core, the circumferential flow and the axial flow of the cooling liquid on the outer peripheral surface of the stator core are avoided, the leakage of the cooling liquid from the welding seam in the welded core is prevented, the double-layer flow channels are used to improve the cooling effect of the cooling liquid on the stator, the cooling liquid input by the housing is received by the notch of the first core, the cooling liquid in the notch is delivered into two first through holes in a group of first through holes adjacent to the notch in the axial direction to realize staggered connection, thereby realizing the circumferential flow and the axial flow of the cooling liquid in the stator, and the leakage of the cooling liquid is further prevented without arranging the flow equalization groove on the housing. A part of the third through holes of the second core are connected with the first through holes and the second through holes, the cooling liquid in the first through holes is delivered into the second through holes, and the double-layer cooling flow channels are formed.

[0092] The oil-cooled motor 21 provided by the embodiment of the present application will be described in detail below.

[0093] Figure 5 is an exploded schematic view of the first core 210 provided by the embodiment of the present application, Figure 6 is an exploded schematic view of the second core 220 provided by the embodiment of the present application, Figure 7 is a schematic view of the flow path of the cooling liquid provided by the embodiment of the present application, Figure 8 is a schematic view of the stator 200 provided by the embodiment of the present application, Figure 9 is a sectional view of the stator 200 in Figure 8 along A-A, Figure 10 is a sectional view of the stator 200 in Figure 8 along B-B. Wherein, Figure 9 and Figure 10 the arrows in and represent the flow direction of the cooling liquid.

[0094] In an embodiment, as shown in Figure 3 , the housing 100 of the oil-cooled motor 21 is used to accommodate and fix the stator 200 of the oil-cooled motor 21, as shown in Figure 4 , the stator 200 includes the first core 210 and two second cores 220, and the first core 210 is arranged between the two second cores 220 in the axial direction O of the stator 200. Wherein, as shown in Figure 5As shown, the first core 210 includes at least two groups of first through holes 211, a plurality of second through holes 212, and a gap 213. The at least two groups of first through holes 211 are arranged in an axial direction O of the stator 200. Each group of first through holes 211 includes a plurality of first through holes 2110 arranged in a circumferential direction C of the stator 200. The gap 213 is arranged between two adjacent first through holes 2110 in a group of first through holes 211a in the circumferential direction C of the stator 200. An opening direction of the gap 213 is away from an axis of the stator 200 in a radial direction R of the stator 200. The gap 213 is used to receive the cooling liquid output by the shell 100 and deliver the cooling liquid to two adjacent first through holes 2110 in another group of first through holes 211b adjacent to the group of first through holes 211a. Each second through hole 212 is arranged between a first through hole 2110 and the axis of the stator 200 in the radial direction R of the stator 200. The plurality of second through holes 212 are arranged in the circumferential direction C of the stator 200. Figure 4 、 Figure 6 to Figure 10 As shown, each second core 220 includes a plurality of groups of third through holes 221. The plurality of groups of third through holes 221 are arranged in the circumferential direction C of the stator 200. Each of a portion of third through holes 221a in each group of third through holes 221 is used to communicate one first through hole 2110 and one second through hole 212. Each of another portion of third through holes 221b in each group of third through holes 221 communicates another second through hole 212 and does not communicate a first through hole 2110.

[0095] In the embodiments of the present application, the at least two groups of first through holes 211 are arranged in the axial direction O of the stator 200. Each group of first through holes 211 includes a plurality of first through holes 2110 arranged in the circumferential direction C of the stator 200, so that the first through holes 2110 in the at least two groups of first through holes 211 can be communicated.

[0096] In the embodiment of the present application, the notch 213 of the first core 210 is arranged between two adjacent first through holes 2110 in a group of first through holes 211a along the circumferential direction C of the stator 200, and the opening direction of the notch 213 is away from the axis of the stator 200 along the radial direction R of the stator 200. The notch 213 is used to receive the cooling liquid output by the shell 100 and transport it to two adjacent first through holes 2110 in another group of first through holes 211b adjacent to the group of first through holes 211a. Thus, the notch 213 can input the cooling liquid received from the shell 100 into the first through holes 2110 of the first core 210, so that the cooling liquid flows inside the first core 210 of the stator 200, thereby preventing the cooling liquid from leaking through the welds on the outer circumferential surface of the stator core 200a, increasing the amount of cooling liquid effectively participating in the cooling of the stator 200 in the first core 210 of the stator 200, and ensuring the cooling effect of the stator 200. In addition, the axial flow and circumferential flow of the cooling liquid in the first core 210 of the stator 200 can be achieved without setting a flow equalizing groove on the shell 100.

[0097] In the embodiment of the present application, each of a part of the third through holes 221a in each group of the third through holes 221 of the second core 220 is used to communicate one first through hole 2110 and one second through hole 212, so that the cooling liquid in the first through hole 2110 of the first core 210 can be input into the second through hole 212 through a part of the third through holes 221a of the second core 220, and each second through hole 212 is arranged between the first through hole 2110 and the axis of the stator 200 along the radial direction R of the stator 200. Thus, the first core 210 of the stator 200 has double-layer cooling liquid flow channels inside along the radial direction R of the stator 200, thereby facilitating the increase of the heat dissipation area of the cooling liquid and the first core 210 of the stator 200, and facilitating the improvement of the cooling effect of the stator 200. In addition, the second through hole 212 can be closer to the stator winding fixed by the first core 210 of the stator, and it is more convenient to quickly dissipate the large amount of heat generated by the stator winding through the cooling liquid in the second through hole 212.

[0098] In the embodiment of the present application, each of another part of the third through holes 221b in each group of the third through holes 221 communicates with another second through hole 212 and does not communicate with the first through hole 2110, so that another part of the third through holes 221b in each second core 220 does not directly receive the cooling liquid output from the first through hole 2110. Each of another part of the third through holes 221b in one second core 220a can receive the cooling liquid in the first through hole 2110 transported from a part of the third through holes 221a in another second core 220b through another second through hole 212, so that the flow path of the cooling liquid in the stator 200 is longer, thereby facilitating more uniform heat dissipation of the stator 200.

[0099] In the embodiment of the present application, each second core 220 includes a plurality of groups of third through holes 221, the plurality of groups of third through holes 221 are arranged at intervals along the circumferential direction C of the stator 200, each of a part of the third through holes 221a in each group of third through holes 221 is used to communicate one first through hole 2110 and one second through hole 212, and each of another part of the third through holes 221b in each group of third through holes 221 communicates with another second through hole 212 and does not communicate with the first through hole 2110. Thus, the cooling liquid has a plurality of double-layer cooling liquid flow channels inside the stator core 200a, and the flow directions of the cooling liquid in the adjacent two double-layer cooling liquid flow channels along the circumferential direction C of the stator 200 are opposite, thereby facilitating more uniform heat dissipation of the cooling liquid to the stator 200 and improving the cooling effect of the stator 200.

[0100] In the embodiment of the present application, the gap 213 of the first core 210 receives the cooling liquid input by the shell 100, and the cooling liquid in the gap 213 is transported into two first through holes 2110 in another group of first through holes 211b adjacent to the gap 213 along the axial direction O of the stator 200 to realize staggered communication, thereby realizing circumferential flow and axial flow of the cooling liquid in the stator 200, so that a flow uniformizing groove does not need to be arranged on the shell 100, and leakage of the cooling liquid is prevented. The cooling liquid flows on the outer circumferential surface of the stator 200, thereby preventing the cooling liquid from leaking from the weld of the stator core 200a, increasing the amount of cooling liquid effectively participating in cooling the stator 200, and facilitating improvement of the cooling effect of the stator 200. A part of the third through holes 221a of the second core 220 communicate the first through hole 2110 and the second through hole 212, and the cooling liquid in the first through hole 2110 is transported to the second through hole 212, thereby forming a double-layer cooling liquid flow channel inside the stator core 200a, and facilitating improvement of the cooling effect of the stator 200.

[0101] In an embodiment, as shown in Figure 3 the shell 100 includes a shell liquid inlet hole 110, which is aligned with the gap 213 of the first core 210 along the radial direction R of the stator 200, so that the cooling liquid input by the shell liquid inlet hole 110 can enter the gap 213 of the first core 210 in the shortest path, and then be transported into the first through hole 2110 through the gap 213, thereby facilitating improvement of the cooling effect of the stator 200.

[0102] In an embodiment, as shown in Figure 5 along the axial direction O of the stator 200, one first through hole 2110 in one group of first through holes 211a is used to communicate with the adjacent two first through holes 2110 in another group of first through holes 211b. Along the circumferential direction C of the stator 200, the circumferential length of each first through hole 2110 is greater than the spacing between the adjacent two first through holes 2110 in each group of first through holes 211.

[0103] In the embodiment of the present application, one first through hole 2110 in one group of first through holes 211a is used to communicate with the adjacent two first through holes 2110 in another group of first through holes 211b, so that at least two groups of first through holes 211 in the first core 210 can realize axial communication, so that the cooling liquid can realize axial flow and circumferential flow in at least two groups of first through holes 211 of the first core 210.

[0104] In the embodiment of the present application, along the circumferential direction C of the stator 200, the circumferential length of each first through hole 2110 is denoted as L1, and the distance between the adjacent two first through holes 2110 in each group of first through holes 211 is denoted as L2, L1>L2, so that after the at least two groups of first through holes 211 are arranged in the axial direction O of the stator 200, the first through hole 2110 in one group of first through holes 211a will not be blocked by the core part 215 between the adjacent two first through holes 2110 in another group of first through holes 211b, thereby facilitating the axial communication and circumferential communication between the at least two groups of first through holes 211, so that the cooling liquid can realize axial flow and circumferential flow in the at least two groups of first through holes 211 of the first core 210.

[0105] In one embodiment, as shown in Figure 5 along the circumferential direction C of the stator 200, the distance between the notch 213 and any one of the adjacent two first through holes 2110 in one group of first through holes 211a is equal to the distance between any other adjacent two first through holes 2110 in one group of first through holes 211a. Along the circumferential direction C of the stator 200, the length of the notch 213 is equal to the length of the first through hole 2110.

[0106] In the embodiment of the present application, along the circumferential direction C of the stator 200, the distance between the notch 213 and any one of the adjacent two first through holes 2110 in one group of first through holes 211a is denoted as L3, and the distance between any other adjacent two first through holes 2110 in one group of first through holes 211a is denoted as L2, L3=L2, so that the core part 216 between the notch 213 and the first through hole 2110 in one group of first through holes 211a will not affect the communication between the first through hole 2110 in one group of first through holes 211a and the first through hole 2110 in another group of first through holes 211b.

[0107] In the embodiment of the present application, along the circumferential direction C of the stator 200, the length of the notch 213 is denoted as L4, and the length of the first through hole 2110 is denoted as L1, L4=L1, so that the arrangement of the notch 213 and the first through hole 2110 in the first core 210 is more regular.

[0108] Figure 11 is a schematic view of the first core 210 provided in the embodiment of the present application.

[0109] In an embodiment, as shown in Figure 11 The length of each first through hole 2110 along the circumferential direction C of the stator 200 is greater than the length of each first through hole 2110 along the radial direction R of the stator 200.

[0110] In the embodiments of the present application, as shown in Figure 5 and Figure 11 The length of each first through hole 2110 along the circumferential direction C of the stator 200 is greater than the length of each first through hole 2110 along the radial direction R of the stator 200, so that the first through hole 2110 is in the shape of a circular arc, which is conducive to the axial flow and circumferential flow of a small amount of cooling liquid, and the first through hole 2110 is filled faster, which is conducive to improving the cooling efficiency of the stator 200. The length of each first through hole 2110 along the circumferential direction C of the stator 200 is greater, which facilitates the axial communication between the first through holes 2110 in different groups of first through holes 211, and also makes it possible to arrange a smaller number of first through holes 2110 along the circumferential direction C of the stator 200 to achieve axial communication, thus simplifying the structure.

[0111] In an embodiment, as shown in Figure 5 and Figure 11 The first core 210 includes at least two groups of first laminations 214 stacked along the axial direction O of the stator 200, each group of first laminations 214 includes a plurality of first laminations 214 stacked along the axial direction O of the stator 200, each first lamination 214 includes a plurality of first sub-through holes 2141 and a plurality of second sub-through holes 2142, each first sub-through hole 2141 penetrates the first lamination 214 along the axial direction O of the first lamination 214, and the plurality of first sub-through holes 2141 are arranged at intervals along the circumferential direction C of the first lamination 214, each second sub-through hole 2142 penetrates the first lamination 214 along the axial direction O of the first lamination 214, and the plurality of second sub-through holes 2142 are arranged at intervals along the circumferential direction C of the first lamination 214. As shown in Figure 5 One group of first laminations 214 is arranged in a staggered manner along the circumferential direction C of the stator 200 with another group of first laminations 214, the plurality of first sub-through holes 2141 of each first lamination 214 in one group of first laminations 214 are aligned one by one along the axial direction O of the stator 200 to communicate with the plurality of first sub-through holes 2141 of the adjacent another first lamination 214 to form a group of first through holes 211a, and the plurality of first sub-through holes 2141 of each first lamination 214 in another group of first laminations 214 are aligned one by one along the axial direction O of the stator 200 to communicate with the plurality of first sub-through holes 2141 of the adjacent another first lamination 214 to form another group of first through holes 211b. The plurality of second sub-through holes 2142 of each first lamination 214 in the at least two groups of first laminations 214 are aligned one by one along the axial direction O of the stator 200 to communicate with the plurality of second sub-through holes 2142 of the adjacent another first lamination 214 to form a plurality of second through holes 212.

[0112] The axial direction O of the first punching sheet 214 is the same as the axial direction O of the stator 200, and the circumferential direction C of the first punching sheet 214 is the same as the circumferential direction C of the stator 200.

[0113] In an embodiment, the outer circumferential surface of each first punching sheet 214 comprises an opening 2143, the opening direction of the opening 2143 is away from the center hole of the first punching sheet 214 along the radial direction R of the first punching sheet 214, and the openings 2143 in at least some of the first punching sheets 214 in the group of first punching sheets 214 are aligned and communicated along the axial direction O of the stator 200 to form a gap 213 of the first iron core 210 for receiving the cooling liquid input by the shell 100.

[0114] The radial direction R of the first punching sheet 214 is the same as the radial direction R of the stator 200.

[0115] Figure 12 is a schematic view of the second iron core 220 provided in an embodiment of the present application.

[0116] In an embodiment, as shown in Figure 11 and Figure 12 , along the circumferential direction C of the stator 200, the maximum length of each third through hole 2210 in the second iron core 220 is less than the length of the iron core part 215 between the adjacent two first through holes 2110 in each group of first through holes 211.

[0117] In an embodiment of the present application, as shown in Figure 7 , Figure 11 and Figure 12 , along the circumferential direction C of the stator 200, as shown in Figure 12 , the maximum length of each third through hole 2210 in the second iron core 220 is denoted as L5, as shown in Figure 11 , the length of the iron core part 215 between the adjacent two first through holes 2110 in each group of first through holes 211 is denoted as L2, and L5

[0118] In an embodiment, as shown in Figure 7 , Figure 11 and Figure 12As shown, the sum of the maximum lengths of the three adjacent third through holes 2210 in the second core 220 along the circumferential direction C of the stator 200 is less than the length of the first through hole 2110, so that two third through holes 2210 in a part of the third through holes 221a in the second core 220 can be communicated by one first through hole 2110.

[0119] In an embodiment, as shown in Figure 12 , the length of each third through hole 2210 along the radial direction R of the stator 200 is greater than the length of the third through hole 221 along the circumferential direction C of the stator 200. Figure 11 and Figure 12 , the length of each third through hole 2210 along the radial direction R of the stator 200 is greater than the distance between one first through hole 2110 and one second through hole 212.

[0120] In the embodiment of the present application, as shown in Figure 9 and Figure 12 , the length of each third through hole 2210 along the radial direction R of the stator 200 is denoted as L6, the length of the third through hole 221 along the circumferential direction C of the stator 200 is denoted as L5, L6>L5, L6 is greater, which is convenient for realizing the communication between the first through hole 2110 and the second through hole 212 by a part of the third through holes 221a in the second core 220, so that the inner part of the stator core 200a has a double-layer cooling flow channel, so that the cooling liquid can better dissipate heat for the stator winding 200b, which is beneficial to improve the cooling effect of the stator 200.

[0121] In the embodiment of the present application, as shown in Figure 9 , Figure 11 and Figure 12 , the length of each third through hole 2210 along the radial direction R of the stator 200 is L6, the distance between one first through hole 2110 and one second through hole 212 is denoted as L7, L6>L7, L6 is greater, which is more convenient for conveying the cooling liquid in the first through hole 2110 to the second through hole 212 along the radial direction R of the stator 200 by a part of the third through holes 221a in each group of third through holes 221 in the second core 220, so that the inner part of the stator core 200a has a double-layer cooling flow channel, so that the cooling liquid can better dissipate heat for the stator winding 200b, which is beneficial to improve the cooling effect of the stator 200.

[0122] Among them, Figure 12 the stator winding 200b only represents the schematic position of the winding, and does not represent the specific structure.

[0123] In an embodiment, as shown in Figure 7 , Figure 11 and Figure 12As shown, the third through hole 2210 includes two ends 2211, 2212 arranged oppositely along the radial direction R of the stator 200, one end 2211 of the third through hole 2210 is used to communicate with one first through hole 2110, and the other end 2212 of the third through hole 2210 is used to communicate with one second through hole 212. Wherein, along the circumferential direction C of the stator 200, the length of the one end 2211 is greater than the length of the other end 2212.

[0124] In the embodiment of the present application, along the circumferential direction C of the stator 200, the length of the one end 2211 is greater than the length of the other end 2212, and the circumferential length of the one end 2211 to the other end 2212 of the third through hole 2210 is reduced, which can make the flow rate of the cooling liquid flowing from the one end 2211 to the other end 2212 faster. The one end 2211 of the third through hole 2210 communicating with the first through hole 2110 is larger, which facilitates the one end 2211 to receive the cooling liquid of the first through hole 2110. The other end 2212 of the third through hole 2210 communicating with the second through hole 212 is smaller, which facilitates the other end 2212 to deliver the cooling liquid with faster flow rate to the second through hole 212, which is conducive to realizing the communication between the first through hole 2110 and the second through hole 212 through the third through hole 2210, and the faster flow rate of the cooling liquid is conducive to improving the cooling efficiency of the stator 200.

[0125] In one embodiment, as shown in Figure 4 and Figure 7 two second cores 220 are arranged in reverse along the axial direction O of the stator 200. Wherein, along the axial direction O of the stator 200, a part of the third through holes 221a in the plurality of groups of third through holes 221 of one second core 220a is aligned with another part of the third through holes 221b in the plurality of groups of third through holes 221 of the other second core 220b. Along the axial direction O of the stator 200, at least one third through hole 2210a in at least one group of third through holes 221 of one second core 220a is not aligned with any one of the plurality of groups of third through holes 221 of the other second core 220b.

[0126] In the embodiment of the present application, along the axial direction O of the stator 200, a part of the third through holes 221a in the plurality of groups of third through holes 221 of one second core 220a are aligned with another part of the third through holes 221b in the plurality of groups of third through holes 221 of another second core 220b. Thus, the part of the third through holes 221a in the plurality of groups of third through holes 221 of one second core 220a can receive the cooling liquid from the first through holes 2110, and deliver the cooling liquid to the another part of the third through holes 221b in the plurality of groups of third through holes 221 of another second core 220b through the second through holes 212, so that the cooling liquid can be delivered from one second core 220a to another second core 220b, achieving side oil delivery, making the flow path of the cooling liquid in the stator core 200a longer, so as to reduce the large flow rate difference caused by the large difference in the flow path length of the cooling liquid in the stator core 200a, balance the flow rate of the cooling liquid in the stator core 200a, and facilitate more uniform heat dissipation of the cooling liquid to the stator 200, improve the heat dissipation effect of the stator 200, and ensure normal operation of the oil-cooled motor 21.

[0127] In the embodiment of the present application, at least one third through hole 2210 in at least one group of third through holes 221 of one second core 220a that is not aligned with any of the plurality of groups of third through holes 221 of another second core 220b is denoted as third through hole 2210a. At least one third through hole 2210a in at least one group of third through holes 221 of one second core 220a that is not aligned with any of the plurality of groups of third through holes 221 of another second core 220b makes the cooling path of the cooling liquid in the stator core 200a more diverse.

[0128] In an embodiment, as Figure 6 and Figure 7As shown, each second core 220 includes two groups of laminations 222 stacked along the axial direction O of the stator 200, each group of laminations 222 includes a plurality of laminations 222 stacked along the axial direction O of the stator 200, a part 223 of each lamination 222 includes a plurality of third sub-through holes 2221, each third sub-through hole 2221 penetrates the lamination 222 along the axial direction O of the lamination 222, the plurality of third sub-through holes 2221 are arranged in intervals along the circumferential direction C of the lamination 222, the plurality of third sub-through holes 2221 of one group of laminations 222a and the plurality of third sub-through holes 2221 of another group of laminations 222b are arranged in intervals along the circumferential direction C of the stator 200 in sequence, and the one group of laminations 222a is arranged adjacent to the first core 210. The plurality of third sub-through holes 2221 of each lamination 222 in the one group of laminations 222a are aligned one-to-one along the axial direction O of the stator 200 and connected in communication with the plurality of third sub-through holes 2221 of an adjacent other lamination 222 to form a part of third through holes 221a of the second core 220. The plurality of third sub-through holes 2221 of each lamination 222 in the other group of laminations 222b are aligned one-to-one along the axial direction O of the stator 200 and connected in communication with the plurality of third sub-through holes 2221 of an adjacent other lamination 222 to form another part of third through holes 221b of the second core 220.

[0129] In the embodiment of the present application, the plurality of third sub-through holes 2221 of the one group of laminations 222a and the plurality of third sub-through holes 2221 of the other group of laminations 222b are arranged in intervals along the circumferential direction C of the stator 200 in sequence, so that the plurality of third sub-through holes 2221 between the two groups of laminations 222 are not connected in communication along the axial direction O of the stator 200, facilitating the formation of the part of third through holes 221a and the other part of third through holes 221b of the second core 220 through the plurality of third sub-through holes 2221 of the two groups of laminations 222 respectively.

[0130] In the embodiment of the present application, the plurality of third sub-through holes 2221 of each lamination 222 in the one group of laminations 222a are aligned one-to-one along the axial direction O of the stator 200 and connected in communication with the plurality of third sub-through holes 2221 of an adjacent other lamination 222 to form the part of third through holes 221a of the second core 220, and the part of third through holes 221a of the second core 220 is directly formed by superposition of the plurality of third sub-through holes 2221 in the one group of laminations 222a, which is beneficial to reduce assembly complexity, simplify the structure of the stator 200, and reduce production cost.

[0131] In the embodiment of the present application, the plurality of third sub-through holes 2221 of each punching sheet 222 in the other group of punching sheets 222b are respectively aligned in one-to-one correspondence with the plurality of third sub-through holes 2221 of an adjacent punching sheet 222 along the axial direction O of the stator 200 to form another part of the third through holes 221b of the second iron core 220, and the another part of the third through holes 221b of the second iron core 220 is directly formed by superimposition of the plurality of third sub-through holes 2221 in the other group of punching sheets 222b, which is conducive to reducing assembly complexity, simplifying the structure of the stator 200, and reducing production cost.

[0132] In an embodiment, as shown in Figure 6 、 Figure 7 and Figure 11 , the other part 224 of each punching sheet 222 includes a plurality of fourth through holes 2222, the other part 224 of each punching sheet 222 is arranged adjacent to the part 223 of the punching sheet 222 along the circumferential direction C of the stator 200, and the plurality of fourth through holes 2222 are arranged at intervals along the circumferential direction of the punching sheet 222, each fourth through hole 2222 is used to communicate the plurality of second through holes 212, and at least one fourth through hole 2222a is further used to communicate one first through hole 2110a. Among them, along the circumferential direction C of the stator 200, the length of the fourth through hole 2222 is greater than or equal to the interval between the adjacent at least two second through holes 212. Along the radial direction R of the stator 200, the length of at least one fourth through hole 2222a is greater than the interval between one first through hole 2110 and one second through hole 212.

[0133] In the embodiment of the present application, the fourth through hole 2222 that communicates with the first through hole 2110 is denoted as the fourth through hole 2222a, and the first through hole 2110 that communicates with the fourth through hole 2222 is denoted as the first through hole 2110a. The second through holes 212 located at the bottom of the stator 200 after assembly of the stator 200 often receive cooling liquid with low flow rate or almost no cooling liquid flowing therethrough, which affects the cooling effect of the stator 200. By providing the fourth through hole 2222 in the other part 224 of each punching sheet 222 of the second iron core 220, each fourth through hole 2222 is used to communicate the plurality of second through holes 212, and at least one fourth through hole 2222a is further used to communicate one first through hole 2110a, so that the fourth through hole 2222a can directly receive the cooling liquid delivered by the first through hole 2110a of the first iron core 210 and deliver it into the plurality of second through holes 212 at the bottom of the stator 200, so that the cooling liquid with high flow rate in the first through hole 2110a can flow through the plurality of second through holes 212 at the bottom of the stator 200, and more cooling liquid can also flow into the interior of the stator iron core 200a at the bottom of the stator 200 for cooling and temperature reduction, which is conducive to improving the cooling effect of the stator 200.

[0134] In the embodiments of the present application, along the circumferential direction C of the stator 200, the length of the fourth through hole 2222 is greater than or equal to the interval between the adjacent at least two second through holes 212, so that the fourth through hole 2222 can simultaneously communicate with the at least two second through holes 212, which is conducive to the fourth through hole 2222 to simultaneously input the cooling liquid into the plurality of second through holes 212, or to simultaneously receive the cooling liquid input from the plurality of second through holes 212, so that the cooperation of the fourth through hole 2222 between the two second cores 220 can realize the series connection or parallel connection of the plurality of second through holes 212 at the bottom, which is conducive to improving the cooling effect of the stator 200.

[0135] In the embodiments of the present application, along the radial direction R of the stator 200, the length of the at least one fourth through hole 2222a is greater than the interval between the first through hole 2110 and the second through hole 212, so that the at least one fourth through hole 2222a can be used to directly receive the cooling liquid in the first through hole 2110a of the first core 210, and the cooling liquid with a higher flow rate can be directly transported from the first through hole 2110a to the second through hole 212 at the bottom of the stator 200, so that the cooling effect at the bottom of the stator 200 is better, thereby being conducive to improving the cooling effect of the stator 200.

[0136] In an embodiment, as shown in Figure 6 and Figure 7 , the plurality of fourth through holes 2222 of the two groups of laminations 222 of each second core 220 are arranged in a staggered manner along the circumferential direction C of the stator 200, and the plurality of fourth through holes 2222 in one group of laminations 222a are in communication with the plurality of fourth through holes 2222 in the other group of laminations 222b along the axial direction of the stator 200.

[0137] In an embodiment, as shown in Figure 4 and Figure 7 , the plurality of fourth through holes 2222 of one second core 220a are aligned in a staggered manner with the plurality of fourth through holes 2222 of another second core 220b along the circumferential direction C of the stator 200. Along the circumferential direction C of the stator 200, one fourth through hole 2222b in one second core 220a is arranged adjacent to one third through hole 2210b in another part of the third through holes 221b in the other second core 220b, and the one fourth through hole 2222b is used to communicate with the one third through hole 2210b in the another part of the third through holes 221b through the second through hole 212.

[0138] In the embodiment of the present application, the plurality of fourth through holes 2222 of one second core 220a and the plurality of fourth through holes 2222 of another second core 220b are misaligned and aligned along the circumferential direction C of the stator 200, so that the fourth through holes 2222 of the two second cores 220 can be communicated through the second through holes 212, so that the series connection and parallel connection of the plurality of second through holes 212 at the bottom of the stator 200 can be realized through the cooperation of the fourth through holes 2222 between the two second cores 220, so that the cooling liquid can flow through most of the second through holes 212 at the bottom of the stator 200, which is beneficial to improve the cooling effect of the stator 200.

[0139] In the embodiment of the present application, the fourth through hole 2222 adjacent to the other part of the third through hole 221b of the other second core 220b in one second core 220a is denoted as fourth through hole 2222b, and one of the other part of the third through hole 221b adjacent to the fourth through hole 2222b is denoted as 2210b. Along the circumferential direction C of the stator 200, one fourth through hole 2222b in one second core 220a is arranged adjacent to one third through hole 2210b in the other part of the third through hole 221b in the other second core 220b, and one fourth through hole 2222b is used to communicate one third through hole 2210b in the other part of the third through hole 221b through the second through hole 212, so that the cooling liquid from the first through hole 2110 received by the second through hole 212 at the bottom can be input into one third through hole 2210b in the other part of the third through hole 221b, and the cooling liquid is provided for one third through hole 2210b in the other part of the third through hole 221b.

[0140] In one embodiment, as shown in Figure 3 and Figure 4 The stator 200 further comprises two third cores 230, one third core 230a is arranged on the side away from the first core 210 of one second core 220a along the axial direction O of the stator 200, and the other third core 230b is arranged on the side away from the first core 210 of the other second core 220b along the axial direction O of the stator 200, each third core 230 comprises a plurality of fifth through holes 231, and the end winding 240 of the stator 200 is exposed to the plurality of fifth through holes 231, and the plurality of fifth through holes 231 are arranged at intervals along the circumferential direction C of the stator 200. As shown in Figure 9 and Figure 10 Among them, along the axial direction O of the stator 200, each third through hole 2210 in the other part of the third through hole 221b in each second core 220 is used to communicate one fifth through hole 231.

[0141] In the embodiment of the present application, each third iron core 230 comprises a plurality of fifth through holes 231, and the end winding 240 of the stator 200 is exposed to the plurality of fifth through holes 231, so that the cooling liquid sprayed from the fifth through holes 231 can be sprayed to the end winding 240 to cool the end winding 240.

[0142] In the embodiment of the present application, along the axial direction O of the stator 200, each third through hole 2210 in the other part of the third through holes 221b in each second iron core 220 is used to communicate with one fifth through hole 231, so that each third through hole 2210 in the other part of the third through holes 221b in each second iron core 220 can receive the cooling liquid sprayed from the fifth through hole 231 from the opposite second iron core 220. Since the cooling liquid sprayed from the plurality of fifth through holes 231 of each third iron core 230 is all from the oil supply of the opposite second iron core 220, the flow rates of the cooling liquid in the plurality of fifth through holes 231 of each third iron core 230 are equivalent, so that the heat dissipation effects of the cooling liquid sprayed from the plurality of fifth through holes 231 are equivalent, so that the end winding 240 is cooled more evenly, which is beneficial to prevent the end winding 240 from generating local hot spots and improve the cooling effect of the stator 200.

[0143] In an embodiment, as shown in Figure 9 and Figure 10 , the axis direction of each fifth through hole 231 in the third iron core 230 intersects with the axial direction O of the stator 200, and the axis direction of the fifth through hole 231 is deflected toward the axis of the stator 200, so that the fifth through hole 231 can perform centripetal oil injection on the end winding 240, which is beneficial to improve the cooling effect of the end winding 240.

[0144] In another embodiment, the axis of each fifth through hole 231 in the third iron core 230 is the same as the axial direction O of the stator 200, so that the fifth through hole 231 can perform parallel oil injection on the end winding 240, which is beneficial to improve the cooling effect of the end winding 240.

[0145] In an embodiment, the fifth through holes 231 of the two third iron cores 230 located at both ends of the stator 200 are far away from the winding slots of the third iron core 230, and the third iron core 230 will block the second through holes 212 close to the winding slots, so that the paint dripping and fixing of the stator winding 200b will not block the double-layer cooling flow channel in the stator iron core 200a, and the cooling effect of the stator 200 is guaranteed.

[0146] In an embodiment, as shown in Figure 4As shown, each third core 230 includes a plurality of third laminations 232 stacked along the axial direction O of the stator 200, the plurality of third laminations 232 are rotationally stacked along the axial direction O of the stator 200, each third lamination 232 includes a plurality of fifth sub-through holes 2321, each fifth sub-through hole 2321 penetrates the third lamination 232 along the axial direction O of the third lamination 232, the plurality of fifth sub-through holes 2321 are arranged at intervals along the circumferential direction C of the third lamination 232, one third lamination 232 is arranged adjacent to another third lamination 232. Among them, along the axial direction O of the stator 200, the plurality of fifth sub-through holes 2321 of one third lamination 232 are used to communicate with the plurality of fifth sub-through holes 2321 of another lamination 222 to form a plurality of fifth through holes 231 of the third core 230.

[0147] Among them, the axial direction O of the third lamination 232 is the same as the axial direction O of the stator 200, and the circumferential direction C of the third lamination 232 is the same as the circumferential direction C of the stator 200.

[0148] In an embodiment, the first core 210 is formed by the first lamination 214, the second core 220 is formed by the lamination 222, and the third core 230 is formed by the third lamination 232. In the embodiment of the present application, the double-layer cooling flow channel in the stator core 200a can be realized by using three kinds of lamination structures, the mold is simple, and the cost is low.

[0149] In an embodiment, as shown in Figure 4 、 Figure 6 、 Figure 7 and Figure 9 , the notch 213 receives the cooling liquid input by the shell 100, the notch 213 delivers the cooling liquid into at least two groups of first through holes 211 of the first core 210, the cooling liquid output by one first through hole 2110 of one group of laminations 222a close to one second core 220a is input into one third through hole 2210 of a part of third through holes 221a of one group of laminations 222a of one second core 220a, the cooling liquid is input into one second through hole 212a of the first core 210 through one third through hole 2210 of a part of third through holes 221a of one group of laminations 222a of one second core 220a, flows into one third through hole 2210 of another part of third through holes 221b of another group of laminations 222b of another second core 220b from one second through hole 212a of the first core 210, and then is delivered to one fifth through hole 231 of another third core 230b from one third through hole 2210 of another part of third through holes 221b of another group of laminations 222b of another second core 220b, sprayed to the end winding 240 through the fifth through hole 231 of the another third core 230b, and the end winding 240 is cooled.

[0150] or, as shown in Figure 10As shown, the cooling liquid output from one first through hole 2110 of one group of punched sheets 222a close to another second core 220b enters one third through hole 2210 in a part of third through holes 221a of one group of punched sheets 222a of another second core 220b, is input from one third through hole 2210 in a part of third through holes 221a of one group of punched sheets 222a of another second core 220b into another second through hole 212b of the first core 210, flows from another second through hole 212b of the first core 210 into one third through hole 2210 in another part of third through holes 221b of another group of punched sheets 222b of the first core 210, and is then transported from one third through hole 2210 in another part of third through holes 221b of another group of punched sheets 222b of the first core 210 to one fifth through hole 231 of one third core 230a, sprayed through one fifth through hole 231 of one third core 230a to the end winding 240, and cools the end winding 240. The flow directions of the cooling liquid in one second through hole 212a and another second through hole 212b are opposite. This enables the stator core 200a to realize oil feeding and spraying to the end winding 240 through double-layer cooling flow channels, makes the heat dissipation of the stator 200 more uniform, and also makes the heat dissipation effect of the stator 200 better, which is conducive to improving the continuous power of the oil-cooled motor 21. The oil feeding and spraying on the opposite side also makes the speed of the cooling liquid sprayed from the plurality of fifth through holes 231 not affected by the position of the cooling liquid input to the first through hole 2110 through the gap 213, facilitates the arrangement of the power assembly 20, and also facilitates the uniformity of the spray cooling.

[0151] wherein, Figure 4 The end winding 240 in the figure only represents the schematic position of the end winding 240, and does not represent the specific structure.

[0152] Figure 13 is a comparison chart of the spray flow rates of the end winding oil spraying of the scheme of the present application and the single-layer oil channel scheme. Figure 13 The horizontal coordinate in the figure represents the arrangement serial number of different spray holes of oil spraying, and the vertical coordinate represents the flow rate of the cooling liquid sprayed from the spray hole.

[0153] In one embodiment, as shown in Figure 13 The flow rates of the oil liquid sprayed from each spray hole are quite different, which makes the cooling effect on the end winding 240 different, thereby easily causing local hot spots of the end winding 240. In the scheme of the present application, the flow rates of the cooling liquid sprayed from the fifth through hole 231 of the third core 230 are relatively balanced, which is conducive to making the heat dissipation of the end winding 240 uniform and improving the cooling effect of the stator 200.

[0154] Figure 14is an explosion schematic diagram of the stator 200 provided by another embodiment of the present application, Figure 15 is a schematic diagram of the second core 220 provided by another embodiment of the present application.

[0155] In an embodiment, as shown in Figure 14 and Figure 15 each second core 220 includes a plurality of laminations 222 stacked along the axial direction O of the stator 200, and a portion 223 of each lamination 222 includes a plurality of third sub-through holes 2221, the plurality of third sub-through holes 2221 penetrating the lamination 222 along the axial direction O of the lamination 222, and the plurality of third sub-through holes 2221 are arranged at intervals along the circumferential direction C of the lamination 222, and one lamination 222 is arranged adjacent to another lamination 222. Among them, along the axial direction O of the stator 200, the plurality of third sub-through holes 2221 of one lamination 222 are used to one-to-one align and communicate with the plurality of third sub-through holes 2221 of another lamination 222 to form a plurality of third through holes 221 of the second core 220.

[0156] In the embodiment of the present application, a portion 223 of each lamination 222 includes a plurality of third sub-through holes 2221, and the plurality of third sub-through holes 2221 penetrate the lamination 222 along the axial direction O of the lamination 222, so that the plurality of third sub-through holes 2221 of two adjacent laminations 222 can be communicated along the axial direction O of the stator 200.

[0157] In the embodiment of the present application, one lamination 222 is arranged adjacent to another lamination 222, and along the axial direction O of the stator 200, the plurality of third sub-through holes 2221 of one lamination 222 are used to one-to-one align and communicate with the plurality of third sub-through holes 2221 of another lamination 222 to form a plurality of third through holes 221 of the second core 220, and the plurality of third through holes 221 are directly formed by superimposing the plurality of third sub-through holes 2221 of the plurality of laminations 222, which is beneficial to reduce the assembly complexity of the stator core 200a, simplify the structure of the stator 200, and reduce the production cost.

[0158] Among them, the circumferential direction C of the lamination 222 is the same as the circumferential direction C of the stator 200, and the axial direction O of the lamination 222 is the same as the axial direction O of the stator 200.

[0159] In an embodiment, as shown in Figure 14 and Figure 15 another portion 224 of the plurality of laminations 222 includes a plurality of fourth through holes 2222, and one lamination 222 is arranged adjacent to another lamination 222, and along the axial direction O of the stator 200, the plurality of fourth through holes 2222 of one lamination 222 are used to one-to-one align and communicate with the plurality of fourth through holes 2222 of another lamination 222.

[0160] Figure 16is a schematic view of the stator 200 and the cooling liquid flow path provided by another embodiment of the present application.

[0161] In an embodiment, as shown in Figure 14 and Figure 16 each of the third through holes 2210 in a part of the third through holes 221a of each second iron core 220 communicates with one of the first through holes 2110 near the one group of the first through holes 211 of the second iron core 220, and each of the third through holes 2210 in another part of the third through holes 221b is arranged between two adjacent first through holes 2110 in the circumferential direction C of the stator 200, so that the part of the third through holes 221a of the second iron core 220 can directly receive the cooling liquid output by the first through holes 2110, and the other part of the first through holes 221b can only receive the cooling liquid delivered by the second through holes 212 from the opposite second iron core 220, so that the stator iron core 200a can realize oil delivery and oil spraying on the opposite side, improve the balance of heat dissipation, and improve the cooling effect.

[0162] Figure 17 is a sectional view of the stator 200 provided by another embodiment of the present application, Figure 18 is another sectional view of the stator 200 provided by another embodiment of the present application. In this embodiment, Figure 17 and Figure 18 the arrows in the figures represent the flow direction of the cooling liquid.

[0163] In an embodiment, as shown in Figure 14 and Figure 17 the gap 213 receives the cooling liquid input by the shell 100, the gap 213 delivers the cooling liquid into at least two groups of the first through holes 211 of the first iron core 210, the cooling liquid output by one of the first through holes 2110 near one second iron core 220a is input into one of the third through holes 2210 in a part of the third through holes 221a of one second iron core 220a, the cooling liquid input into one of the third through holes 2210 in a part of the third through holes 221a of one second iron core 220a is input into one of the second through holes 212a of the first iron core 210, the cooling liquid flows from one of the second through holes 212a of the first iron core 210 into one of the third through holes 2210 in another part of the third through holes 221b of the other second iron core 220b, and then the cooling liquid is delivered from one of the third through holes 2210 in another part of the third through holes 221b of the other second iron core 220b to one of the fifth through holes 231 of the other third iron core 230b, and then the cooling liquid is sprayed to the end winding 240 through the fifth through hole 231 of the other third iron core 230b to cool the end winding 240.

[0164] or, as shown in Figure 18As shown, the cooling liquid output from the first through hole 2110 close to the other second core 220b enters a third through hole 2210 in a part of the third through holes 221a of the other second core 220b, is input from the third through hole 2210 in the part of the third through holes 221a of the other second core 220b into the other second through hole 212b of the first core 210, flows from the other second through hole 212b of the first core 210 into a third through hole 2210 in another part of the third through holes 221b of the first core 210, and is then transported from the third through hole 2210 in the other part of the third through holes 221b of the first core 210 to a fifth through hole 231 of a third core 230a, sprayed through the fifth through hole 231 of the third core 230a to the end winding 240, and cools the end winding 240. The flow directions of the cooling liquid in the first through hole 212a and the other second through hole 212b are opposite. This enables the stator core 200a to realize oil feeding and spraying to the end winding 240 through the double-layer cooling flow channel, makes the heat dissipation of the stator 200 more uniform, and also makes the heat dissipation effect of the stator 200 better, which is conducive to improving the continuous power of the oil-cooled motor 21. The oil feeding and spraying mode on the opposite side also makes the speed of the cooling liquid sprayed from the plurality of fifth through holes 231 not affected by the position of the cooling liquid input to the first through hole 2110 through the gap 213, facilitates the arrangement of the power assembly 20, and also facilitates the realization of the uniformity of the spray cooling.

[0165] wherein, Figure 14 The end winding 240 in the above is only a representative position, not a specific structure.

[0166] The oil-cooled motor, power assembly and electric vehicle provided by the embodiments of the present application are described in detail above, and the principles and embodiments of the present application are described by applying specific examples in this paper. The above embodiment description is only used to help understand the method and core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, the specific embodiments and application range will be changed, and the above description should not be understood as a limitation of the present application.

Claims

1. An oil-cooled motor, characterized in that, The housing of the oil-cooled motor is used to house and fix the stator of the oil-cooled motor. The stator includes a first iron core and two second iron cores. The first iron core is stacked between the two second iron cores along the axial direction of the stator, wherein: The first iron core includes at least two sets of first through holes, a plurality of second through holes, and a notch. The at least two sets of first through holes are staggered along the axial direction of the stator. Each set of first through holes includes a plurality of first through holes spaced apart along the circumference of the stator. The notch is spaced apart along the circumference of the stator between two adjacent first through holes in one set of first through holes. The opening direction of the notch is radially away from the axis of the stator. The notch is used to receive coolant output from the housing and deliver it to two adjacent first through holes in another set of first through holes adjacent to the first set of first through holes. Each second through hole is spaced apart along the radial direction of the stator between the first through hole and the axis of the stator. The plurality of second through holes are spaced apart along the circumference of the stator. Each of the second cores includes multiple sets of third through holes, which are arranged at intervals along the circumference of the stator. Each of a portion of the third through holes in each set is used to connect a first through hole and a second through hole, while each of another portion of the third through holes in each set is connected to another second through hole but not to the first through hole.

2. The oil-cooled motor according to claim 1, characterized in that, Along the axial direction of the stator, one of the first through holes in the set of first through holes is used to connect two adjacent first through holes in the other set of first through holes; Along the circumferential direction of the stator, the circumferential length of each first through hole is greater than the distance between two adjacent first through holes in each group of first through holes.

3. The oil-cooled motor according to claim 1 or 2, characterized in that, Along the circumferential direction of the stator, the distance between the notch and any one of the two adjacent first through holes in the group of first through holes is equal to the distance between any other two adjacent first through holes in the group of first through holes; Along the circumference of the stator, the length of the notch is equal to the length of the first through hole.

4. The oil-cooled motor according to any one of claims 1-3, characterized in that, The length of each first through hole along the circumference of the stator is greater than the length of each first through hole along the radial direction of the stator.

5. The oil-cooled motor according to any one of claims 1-4, characterized in that, Along the circumference of the stator, the maximum length of each of the third through holes in the second core is less than the length of the core portion between two adjacent first through holes in each group of first through holes.

6. The oil-cooled motor according to any one of claims 1-5, characterized in that, The length of each of the third through holes along the radial direction of the stator is greater than the length of the third through hole along the circumferential direction of the stator; Along the radial direction of the stator, the length of each of the third through holes is greater than the distance between a first through hole and a second through hole.

7. The oil-cooled motor according to any one of claims 1-6, characterized in that, The third through hole includes two ends arranged opposite each other along the radial direction of the stator. One end of the third through hole is used to connect to a first through hole, and the other end of the third through hole is used to connect to a second through hole, wherein: Along the circumference of the stator, the length of one end is greater than the length of the other end.

8. The oil-cooled motor according to any one of claims 1-7, characterized in that, The two second iron cores are arranged in a flipped configuration along the axial direction of the stator, wherein: Along the axial direction of the stator, a portion of the third through holes in one set of the third through holes of a second iron core is aligned with another portion of the third through holes in one set of the third through holes of another second iron core; Along the axial direction of the stator, at least one of the third through holes in at least one set of the third through holes of one of the second iron cores is not aligned with any one of the multiple sets of the third through holes of the other second iron core.

9. The oil-cooled motor according to claim 8, characterized in that, Each of the second iron cores includes a plurality of laminations stacked along the axial direction of the stator. A portion of each lamination includes a plurality of sets of third sub-through holes that penetrate the lamination along its axial direction. The plurality of sets of third sub-through holes are arranged at circumferential intervals along the lamination, with one lamination arranged adjacent to another. Along the axial direction of the stator, the plurality of third sub-through holes of one lamination are used to align one-to-one with the plurality of third sub-through holes of the other lamination to form the plurality of third through holes of the second core.

10. The oil-cooled motor according to claim 8, characterized in that, Each second core includes two sets of laminations stacked along the axial direction of the stator. Each set of laminations includes multiple laminations stacked along the axial direction of the stator. A portion of each lamination includes multiple third sub-through holes. Each third sub-through hole penetrates the lamination along its axial direction. The multiple third sub-through holes are spaced apart circumferentially along the lamination. The multiple third sub-through holes of one set of laminations and the multiple third sub-through holes of the other set of laminations are sequentially spaced apart circumferentially along the stator. The set of laminations is arranged adjacent to the first core. The plurality of third sub-through holes of each of the set of laminations are respectively aligned one-to-one along the axial direction of the stator and connect with the plurality of third sub-through holes of another adjacent lamination to form the portion of the third through holes of the second core. The plurality of third sub-through holes of each of the other set of laminations are respectively aligned one-to-one along the axial direction of the stator and connect with the plurality of third sub-through holes of the adjacent lamination to form the other part of the third through holes of the second core.

11. The oil-cooled motor according to claim 9 or 10, characterized in that, Another portion of each of the laminations includes a plurality of fourth through holes, the other portion of each lamination being arranged adjacent to the first portion of the lamination along the circumferential direction of the stator, the plurality of fourth through holes being spaced apart along the circumferential direction of the lamination, each fourth through hole being used to connect to a plurality of second through holes, and at least one fourth through hole also being used to connect to a first through hole, wherein: Along the circumferential direction of the stator, the length of the fourth through hole is greater than or equal to the distance between at least two adjacent second through holes; Along the radial direction of the stator, the length of at least one of the fourth through holes is greater than the distance between a first through hole and a second through hole.

12. The oil-cooled motor according to claim 11, characterized in that, The plurality of fourth through holes of one second iron core are misaligned with the plurality of fourth through holes of another second iron core along the circumferential direction of the stator; Along the circumference of the stator, a fourth through hole in one of the second iron cores is arranged adjacent to a third through hole in another portion of the third through holes in another second iron core, wherein the fourth through hole is used to connect the third through hole in the other portion of the third through holes through the second through hole.

13. The oil-cooled motor according to any one of claims 1-12, characterized in that, The stator further includes two third iron cores. One third iron core is arranged along the axial direction of the stator on the side of one second iron core away from the first iron core, and the other third iron core is arranged along the axial direction of the stator on the side of another second iron core away from the first iron core. Each third iron core includes a plurality of fifth through holes. The end windings of the stator are exposed through the plurality of fifth through holes, and the plurality of fifth through holes are arranged at intervals along the circumference of the stator, wherein: Along the axial direction of the stator, each of the third through holes in the other portion of each of the second iron cores is used to connect to a fifth through hole.

14. A powertrain, characterized in that, The powertrain includes a reducer and an oil-cooled motor as described in any one of claims 1-13, wherein the motor shaft of the oil-cooled motor is driven to the input shaft of the reducer.

15. An electric vehicle, characterized in that, The electric vehicle includes a frame and a powertrain as described in claim 14, the powertrain being configured to receive electrical energy supplied by a power battery to drive the wheels.

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