Oil-cooled stator core and oil-cooled driving motor
By designing a coordinated oil-cooled stator core stack, a stepped oil channel structure is formed, which solves the problems of complex structure and failure probability of traditional oil-cooled motor oil injection ring, and achieves efficient cooling efficiency and adaptability.
Patent Information
- Application Number
- CN202510419875.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-04-03
- Publication Date
- 2025-05-13
AI Technical Summary
The oil injection ring structure of traditional oil-cooled motors increases the assembly complexity and cost, and at the same time there is a failure probability, making it difficult to effectively meet the cooling needs of windings of different lengths.
An oil-cooled stator core is designed, and a stepped oil channel structure with different injection angles is formed through the coordinated design of the main lamination set, the first end lamination set and the second end lamination set, which meets the cooling needs of windings of different lengths.
The uniform distribution of cooling oil and differentiated injection angle are achieved, which significantly improves the cooling efficiency of the oil-cooled stator, and has adaptive capabilities, which can automatically adjust the injection angle when the cooling oil flow rate or pressure changes.
Smart Images
Figure CN119995203A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of oil-cooled motors, and in particular to an oil-cooled motor core and an oil-cooled drive motor. Background Art
[0002] As the power density requirements for new energy motors continue to increase, the heat dissipation capacity of the motor stator core is becoming increasingly important. Oil cooling has gradually become an industry trend due to its excellent heat dissipation capacity. The general structure of traditional oil-cooled motors is to add oil spray rings at both ends of the stator core to achieve the effect of oil spraying and cooling the windings. However, the oil spray ring structure increases the difficulty and complexity of the assembly process, as well as the cost and failure probability. Summary of the invention
[0003] The invention provides an oil-cooled stator core for cooling windings of different lengths.
[0004] The technical solution of the present invention is: An oil-cooled stator core comprises: a main lamination group, a first end lamination group and a second end lamination group sequentially stacked on both sides of the main lamination group; The main body lamination group includes a plurality of main body punching sheets, and the plurality of main body punching sheets are rotated and stacked to form a plurality of groups of oil inlet spaces on the outer wall of the main body lamination group, wherein a group of oil inlet spaces includes an oil inlet area and a plurality of main body channels connected with the oil inlet area; The first end lamination stack includes a plurality of main end punching sheets, and the plurality of main end punching sheets are rotated and stacked so that a plurality of first oil passages designed in a stepped shape are formed on the axial surface of the first end lamination stack, and a plurality of main channels of a group of oil inlet spaces merge into one first oil passage; The second end lamination group includes a plurality of secondary end punching sheets, and the plurality of secondary end punching sheets are rotated and stacked so that a plurality of second oil passages designed in a stepped shape are formed in the axial direction of the second end lamination group, and a first oil passage is connected to a second oil passage; Among them, based on the different winding lengths on both sides of the oil-cooled stator, the oil injection angles formed by the second oil channels formed on both sides of the main lamination stack are also different.
[0005] Preferably, the inner circumference of the main body punching sheet is provided with n evenly distributed first core slots, the outer circumference of the main body punching sheet is provided with N evenly distributed steps, and both sides of each step are provided with first welding slots; The angle between the symmetry center line of the step and the symmetry center line of the first welding groove adjacent to the step is a first preset angle.
[0006] Preferably, the inner circumference of the main end punching sheet is provided with n evenly distributed second core slots, and the main end punching sheet is provided with N evenly distributed first oil holes and N second oil holes along the circumferential direction; the outer circumference of the main end punching sheet is provided with N evenly distributed second welding slots and N / 2 third welding slots; The first oil hole and the second oil hole are arranged at intervals, a second welding groove is arranged in the counterclockwise direction of a first oil hole, and a third welding groove is arranged after every two consecutive second welding grooves; The distance between the first oil hole and the center of the main end punching plate is greater than the distance between the second oil hole and the center of the main end punching plate; The angle between the symmetric center lines of two adjacent second welding grooves is the second preset angle, the angle between the symmetric center line of the second welding groove and the symmetric center line of the third welding groove on its adjacent side is the first preset angle, and the angle between the center line of the first oil hole and the symmetric center line of the second welding groove on its adjacent side is the third preset angle; The second preset angle is twice the first preset angle, and the first preset angle is twice the third preset angle.
[0007] Preferably, the inner circumference of the secondary end punching sheet is provided with n evenly distributed third core slots, the secondary end punching sheet is provided with N evenly distributed third oil holes and N fourth oil holes along the circumferential direction, and the outer circumference of the secondary end punching sheet is provided with 2N evenly distributed fourth welding slots; A third oil hole and a fourth oil hole are respectively provided on both sides of the fourth welding groove, and the third oil hole and the fourth oil hole are arranged at intervals; The distance between the third oil hole and the center of the secondary end punching plate is greater than the distance between the fourth oil hole and the center of the secondary end punching plate; The angle between the symmetric center line of the third oil hole and the symmetric center line of the fourth oil hole is the first preset angle, the angle between the symmetric center line of the third oil hole and the symmetric center line of the fourth welding groove adjacent to it is the third preset angle, and the angle between the symmetric center line of the fourth oil hole and the symmetric center line of the fourth welding groove adjacent to it is the third preset angle.
[0008] Preferably, the distance between the first welding groove and the center of the main body punching sheet, the distance between the second welding groove and the center of the main end punching sheet, the distance between the third welding groove and the center of the main end punching sheet, and the distance between the fourth welding groove and the center of the secondary end punching sheet are all equal; The maximum outer diameters of the main punching sheet, the main end punching sheet and the secondary end punching sheet are equal; The inner diameters of the main punching sheet, the main end punching sheet and the secondary end punching sheet are equal; The first welding groove, the second welding groove, the third welding groove and the fourth welding groove have the same shape and the same size.
[0009] Preferably, part of the first welding groove on the main lamination stack and part of the second welding groove on the first end lamination stack are connected and welded and fixed; Part of the first welding groove on the main lamination stack and part of the third welding groove on the first end lamination stack are connected and welded to each other; or Part of the first welding groove on the main lamination stack and part of the second welding groove and part of the third welding groove on the first end lamination stack are connected and welded and fixed.
[0010] Preferably, part of the second welding groove on the first end lamination and part of the fourth welding groove on the second end lamination group are connected and welded and fixed; Part of the third welding groove on the first end lamination and part of the fourth welding groove on the second end lamination group are connected and welded and fixed; Part of the second welding groove, part of the third welding groove on the first end lamination and part of the fourth welding groove on the second end lamination group are connected and welded and fixed.
[0011] Preferably, the symmetric centerline of the step coincides with the symmetric centerline of the first core slot or stator tooth on the inner side of the main body punching sheet; The symmetric center line of the first oil hole and the symmetric center line of the second oil hole respectively coincide with the symmetric center line of the second core slot or the stator tooth inside the main end punching sheet; The symmetric center line of the third oil hole and the symmetric center line of the fourth oil hole coincide with the symmetric center line of the third core slot or the stator tooth on the inner side of the secondary end punching sheet respectively.
[0012] An oil-cooled drive motor comprises the above-mentioned oil-cooled stator core.
[0013] The beneficial effects of the present invention are: The coordinated design of the main lamination group, the first end lamination group and the second end lamination group not only ensures the uniform distribution of the cooling oil in the stator core, but also meets the cooling requirements of the inconsistent winding lengths on both sides through differentiated oil injection angles. This design significantly improves the cooling efficiency of the oil-cooled stator. The main end punching sheet and the secondary end punching sheet make the first and second oil channels formed in a stepped shape. The stepped structure divides the flow of cooling oil into multiple levels, and the oil flow of each level is guided and constrained by the structure; this stratified flow can effectively reduce the turbulence and fluctuation of the oil flow, thereby maintaining the stability of the injection angle. In addition, the stepped oil channel design has a certain degree of adaptive ability; when the flow or pressure of the cooling oil changes, the stepped structure of the first and second oil channels can automatically adapt to the changes and maintain the stability of the injection angle through stratified flow and angle adjustment. BRIEF DESCRIPTION OF THE DRAWINGS
[0014] Figure 1 It is a schematic diagram of the structure of the main punching sheet in the embodiment of the present application; Figure 2 for Figure 1 A magnified schematic diagram of point A; Figure 3 A schematic diagram of a main end punching sheet in an embodiment of the present application; Figure 4 for Figure 3 A partial enlarged schematic diagram of Figure 5 Schematic diagram of a secondary end punching sheet in an embodiment of the present application; Figure 6 for Figure 4 A partial enlarged schematic diagram of Figure 7 This is a schematic diagram of the disassembly of the oil-cooled stator core in the embodiment of the present application; Figure 8 for Figure 7 BB cross-sectional view; Fig. 9 It is a schematic diagram of the assembly of the oil-cooled stator core in the embodiment of the present application; Fig.10 Schematic diagram of the weld of the oil-cooled stator core in the embodiment of the present application. DETAILED DESCRIPTION
[0015] Reference Figures 1 to 10 The embodiment of the present application provides an oil-cooled stator core, comprising: a main lamination group, a first end lamination group and a second end lamination group stacked sequentially on both sides of the main lamination group; the main lamination group comprises a plurality of main punching sheets, and a plurality of main punching sheets are rotated and stacked to form a plurality of groups of oil inlet spaces on the outer wall of the main lamination group, wherein a group of oil inlet spaces comprises an oil inlet area and a plurality of main body channels connected with the oil inlet area; The first end lamination stack includes a plurality of main end punching sheets, and the plurality of main end punching sheets are rotated and stacked so that a plurality of first oil passages designed in a stepped shape are formed on the axial surface of the first end lamination stack, and a plurality of main channels of a group of oil inlet spaces merge into one first oil passage; The second end lamination group includes a plurality of secondary end punching sheets, and the plurality of secondary end punching sheets are rotated and stacked so that a plurality of second oil passages designed in a stepped shape are formed in the axial direction of the second end lamination group, and a first oil passage is connected to a second oil passage; Among them, based on the different winding lengths on both sides of the oil-cooled stator, the oil injection angles formed by the second oil channels formed on both sides of the main lamination stack are also different.
[0016] By rotating and stacking the main punching sheets 1, the first welding grooves on the main punching sheets 1 are staggered at a certain angle, thereby forming a continuous oil inlet area and a main channel on the outer wall. It can be seen from the figure that the area formed between the steps of multiple main punching sheets constitutes the oil inlet area in this embodiment, and multiple oil inlet areas are evenly distributed along the circular axis direction of the main lamination group.
[0017] By rotating and stacking the main end punching sheets, the first oil channel forms a stepped structure. This design allows the cooling oil to gradually adjust its direction during the flow process, providing a basis for the subsequent injection angle. By rotating and stacking the secondary end punching sheets, the second oil channel formed further optimizes the flow path of the cooling oil. Depending on the length of the winding, the stepped structure of the second oil channel can be designed with different inclination angles to adjust the injection angle of the cooling oil. For longer windings, a larger injection angle can be designed to ensure that the cooling oil can cover the far end of the winding; for shorter windings, a smaller injection angle can be designed to avoid waste or over-injection of cooling oil. This customized design significantly improves cooling efficiency.
[0018] In addition, the stepped structure of the first and second oil channels divides the flow of cooling oil into multiple levels, and the oil flow of each level is guided and constrained by the structure; this stratified flow can effectively reduce the turbulence and fluctuation of the oil flow, thereby maintaining the stability of the injection angle. In addition, the stepped oil channel design has a certain degree of adaptive ability; when the flow or pressure of the cooling oil changes, the stepped structure of the first and second oil channels can automatically adapt to the changes and maintain the stability of the injection angle through stratified flow and angle adjustment.
[0019] The optimized cooling structure of the oil-cooled stator core is achieved by rotating and stacking the punching sheets of different designs. The coordinated design of the main lamination group, the first end lamination group and the second end lamination group not only ensures the uniform distribution of the cooling oil in the stator core, but also meets the cooling requirements of the inconsistent winding lengths on both sides through differentiated oil injection angles. This design significantly improves the cooling efficiency of the oil-cooled stator.
[0020] Reference Figure 1 and Figure 2 In this embodiment, the inner circumference of the main body punching sheet 1 is provided with n uniformly distributed first core slots 101, and the stator teeth of the main body punching sheet 1 are formed between adjacent first core slots 101. The outer circumference of the main body punching sheet 1 is provided with N uniformly distributed steps 102, and both sides of each step 102 are provided with first welding slots 103; the angle between the symmetry center line of the step 102 and the symmetry center line of the first welding slot 103 on its adjacent side is the first preset angle a, and the symmetry center line of the step 102 coincides with the symmetry center line of the first core slot 101 or the stator tooth. Among them, the first preset angle a=180° / N.
[0021] The number N of the steps 102 can be divided evenly by the number n of the first core-attaching grooves 101 .
[0022] The N steps 102 are evenly distributed on the outer circumference of the main body punching sheet 1, ensuring that the cooling oil can evenly enter the oil inlet area of the oil-cooled stator core.
[0023] Combination Figures 7 to 10 In the embodiment of the present application, the main body lamination group includes 6 main body laminations 1 (represented as the first main body lamination 11, the second main body lamination 12, the third main body lamination 13, the fourth main body lamination 14, the fifth main body lamination 15 and the sixth main body lamination 16 in sequence), and the 6 main body laminations 1 are stacked in sequence to form the main body lamination group. Among them, for the third main body lamination 13 and the fourth main body lamination 14 located in the middle and the first main body lamination 11 and the sixth main body lamination 16 located in the outermost layer, the steps 102 of these four main body laminations 1 remain opposite in the axial direction; the remaining second main body lamination 12 and the fifth main body lamination 15 are staggered with the aforementioned four main body laminations 1, that is, the steps 102 of the second main body lamination 12 and the fifth main body lamination 15 are no longer opposite to the steps 102 of the aforementioned four main body laminations 1, but the first welding grooves 103 on the six main body laminations 1 always remain opposite, and the six opposite first welding grooves 103 are connected to form a main oil channel. Furthermore, as Fig. 9 The first step 1021 on the fourth main body punch 14, the second step 1022 on the third main body punch 13, the third step 1023 on the second main body punch 12, the fourth step 1024 on the third main body punch 13, the fifth step 1025 on the fourth main body punch 14, and the sixth step 1026 on the fifth main body punch 15 together form an oil inlet area, and the oil inlet area is connected to the main body oil channel.
[0024] The formation of multiple groups of oil inlet areas and main body channels makes the internal flow resistance of the cooling oil smaller; and because the formed oil inlet area has a large contact area with the iron core, the heat dissipation efficiency is high.
[0025] Reference Figure 3 and Figure 4The inner circumference of the main end punching sheet 2 is provided with n uniformly distributed second core slots 201, and the main end punching sheet 2 is provided with N uniformly distributed first oil holes 202 and N second oil holes 203 along the circumferential direction; the outer circumference of the main end punching sheet 2 is provided with N uniformly distributed second welding slots 204 and N / 2 third welding slots 205; the first oil holes 202 and the second oil holes 203 are arranged at intervals, a second welding slot 204 is provided in the counterclockwise direction of a first oil hole 202, and a third welding slot 205 is provided after every two consecutive second welding slots 204; the first oil hole 20 2 and the center of the main end punching plate 2 is larger than the distance between the second oil hole 203 and the center of the main end punching plate 2; the angle between the symmetric center lines of two adjacent second welding grooves 204 is the second preset angle, the angle between the symmetric center line of the second welding groove 204 and the symmetric center line of the third welding groove 205 on its adjacent side is the first preset angle a, and the angle between the center line of the first oil hole 202 and the symmetric center line of the second welding groove 204 on its adjacent side is the third preset angle; the second preset angle is twice the first preset angle, and the first preset angle is twice the third preset angle.
[0026] Reference Figures 7 to 10 In this embodiment, the first end lamination group includes four main end punches 2, namely the first end punch 21, the secondary end punch 22, the third end punch 23 and the fourth end punch 24. By rotating the four main end punches 2, the first oil hole 202 of the first end punch 21, the first oil hole 202 of the secondary end punch 22, the second oil hole 203 of the third end punch 234 and the second oil hole 203 of the fourth end punch 24 form a first oil channel. At the same time, the second welding grooves 204 on the first end punch 21 and the secondary end punch 22 are opposite to each other, but the third welding grooves 205 are not opposite to each other, and the second welding grooves 204 on the third end punch 23 and the fourth end punch 24 are opposite to each other, but the third welding grooves 205 are not opposite to each other.
[0027] Reference Figure 5 and Figure 6The inner circumference of the secondary end punching sheet 3 is provided with n evenly distributed third core slots 301, the secondary end punching sheet 3 is provided with N evenly distributed third oil holes 302 and N fourth oil holes 303 along the circumferential direction, and the outer circumference of the secondary end punching sheet 3 is provided with 2N evenly distributed fourth welding slots 304; a third oil hole 302 and a fourth oil hole 303 are respectively provided on both sides of the fourth welding slot 304, and the third oil hole 302 and the fourth oil hole 303 are arranged at intervals; the third oil hole 302 and the secondary end punching sheet are arranged at intervals; The distance between the centers of the plates 3 is greater than the distance between the fourth oil hole 303 and the center of the secondary end punching plate 3; the angle between the symmetric center line of the third oil hole 302 and the symmetric center line of the fourth oil hole 303 is the first preset angle, the angle between the symmetric center line of the third oil hole 302 and the symmetric center line of the fourth welding groove 304 adjacent to it is the third preset angle, and the angle between the symmetric center line of the fourth oil hole 303 and the symmetric center line of the fourth welding groove 304 adjacent to it is the third preset angle.
[0028] Reference Figures 7 to 10 In this embodiment, the second end lamination group includes two secondary end punching sheets 3, namely the fifth end punching sheet 31 and the sixth end punching sheet 32. By rotating the two secondary end punching sheets 3, the third oil hole 302 of the fifth end punching sheet 31 and the fourth oil hole 303 of the sixth end punching sheet 32 form a second oil channel. At the same time, the fourth welding groove 304 on the fifth end punching sheet 31 and the sixth end punching sheet 32 are opposite.
[0029] Combination Figure 8 It can be seen that the first oil channel and the second oil channel are both formed by two steps. Through stratified flow and angle adjustment, they automatically adapt to changes and maintain the stability of the injection angle.
[0030] In the embodiment of the present application, the distance between the first welding groove 103 and the center of the main body punching sheet 1, the distance between the second welding groove 204 and the center of the main end punching sheet 2, the distance between the third welding groove 205 and the center of the main end punching sheet 2, and the distance between the fourth welding groove 304 and the center of the secondary end punching sheet are all equal; The maximum outer diameters of the main punching sheet 1, the main end punching sheet 2 and the secondary end punching sheet 3 are equal; The inner diameters of the main punching sheet 1, the main end punching sheet 2 and the secondary end punching sheet 3 are equal; The first welding groove 103 , the second welding groove 204 , the third welding groove 205 and the fourth welding groove 304 have the same shape and the same size.
[0031] Combination Fig.10 In this embodiment, the required welding areas total N / 2, evenly distributed around the circumference; the optional welding areas total N / 2, evenly distributed around the circumference; the remaining positions are not welded; the total number of welds is N / 2-N.
[0032] The main punching sheets are rotated and stacked to form the main oil passage and the oil inlet area. After the cooling oil enters the oil inlet area, it flows around, with lower flow resistance and better heat dissipation effect. At the same time, while rotating to form the main oil passage, multiple main punching sheets can still be aligned in the axial direction to form an aligned first welding groove for welding the main laminations; at the same time, the end lamination groups on both sides can form a seal for the main oil passage and form a second oil passage and a third oil passage oblique to the center of the circle through a special rotation alignment method, and can also weld the main punching sheets to the main end punching sheets. At the same time, due to the inconsistent winding lengths at both ends, if the two punching sheets at the end are rotated and stacked, differentiated injection angles at both ends can be achieved.
[0033] It should be noted that the various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.
[0034] Although the preferred embodiments of the present invention have been described, those skilled in the art may make additional changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the embodiments of the present invention.
[0035] It should also be noted that, in this article, the orientation or position relationship indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. is based on the orientation or position relationship shown in the drawings, which is for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation of the present invention. In addition, relational terms such as "first" and "second" are used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply that there is any such actual relationship or order between these entities or operations, nor can they be understood as indicating or implying relative importance. Moreover, the terms "include", "comprise" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or terminal device including a series of elements does not include those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or terminal device. In the absence of more restrictions, the elements defined by the sentence "including one..." do not exclude the existence of other identical elements in the process, method, article or terminal device including the elements.
[0036] The technical solution provided by the present invention is described in detail above. The principle and implementation mode of the present invention are described in this article using specific examples. The description of the above embodiments is only used to help understand the present invention, and the content of this specification should not be understood as limiting the present invention. At the same time, for those skilled in the art, according to the present invention, there will be different forms of changes in the specific implementation mode and application scope. It is not necessary and impossible to list all the implementation modes here, and the obvious changes or modifications derived therefrom are still within the protection scope of the present invention.
Claims
1. An oil-cooled stator core, characterized in that: include: A main lamination group, a first end lamination group and a second end lamination group stacked sequentially on both sides of the main lamination group; The main body lamination group includes a plurality of main body punching sheets, and the plurality of main body punching sheets are rotated and stacked to form a plurality of groups of oil inlet spaces on the outer wall of the main body lamination group, wherein a group of oil inlet spaces includes an oil inlet area and a plurality of main body channels connected with the oil inlet area; The first end lamination stack includes a plurality of main end punching sheets, and the plurality of main end punching sheets are rotated and stacked so that a plurality of first oil passages designed in a stepped shape are formed on the axial surface of the first end lamination stack, and a plurality of main channels of a group of oil inlet spaces merge into one first oil passage; The second end lamination group includes a plurality of secondary end punching sheets, and the plurality of secondary end punching sheets are rotated and stacked so that a plurality of second oil passages designed in a stepped shape are formed in the axial direction of the second end lamination group, and a first oil passage is connected to a second oil passage; Among them, based on the different winding lengths on both sides of the oil-cooled stator, the oil injection angles formed by the second oil channels formed on both sides of the main lamination stack are also different.
2. The oil-cooled stator core according to claim 1, characterized in that: The inner circumference of the main body punching sheet is provided with n evenly distributed first core slots, the outer circumference of the main body punching sheet is provided with N evenly distributed steps, and both sides of each step are provided with first welding slots; The angle between the symmetry center line of the step and the symmetry center line of the first welding groove adjacent to the step is a first preset angle.
3. The oil-cooled stator core according to claim 2, characterized in that: The inner circumference of the main end punching sheet is provided with n evenly distributed second core slots, and the main end punching sheet is provided with N evenly distributed first oil holes and N second oil holes along the circumferential direction; the outer circumference of the main end punching sheet is provided with N evenly distributed second welding slots and N / 2 third welding slots; The first oil hole and the second oil hole are arranged at intervals, a second welding groove is arranged in the counterclockwise direction of a first oil hole, and a third welding groove is arranged after every two consecutive second welding grooves; The distance between the first oil hole and the center of the main end punching plate is greater than the distance between the second oil hole and the center of the main end punching plate; The angle between the symmetric center lines of two adjacent second welding grooves is the second preset angle, the angle between the symmetric center line of the second welding groove and the symmetric center line of the third welding groove on its adjacent side is the first preset angle, and the angle between the center line of the first oil hole and the symmetric center line of the second welding groove on its adjacent side is the third preset angle; The second preset angle is twice the first preset angle, and the first preset angle is twice the third preset angle.
4. The oil-cooled stator core according to claim 3, characterized in that: The inner circumference of the secondary end punching sheet is provided with n evenly distributed third core slots, the secondary end punching sheet is provided with N evenly distributed third oil holes and N evenly distributed fourth oil holes along the circumferential direction, and the outer circumference of the secondary end punching sheet is provided with 2N evenly distributed fourth welding slots; A third oil hole and a fourth oil hole are respectively provided on both sides of the fourth welding groove, and the third oil hole and the fourth oil hole are arranged at intervals; The distance between the third oil hole and the center of the secondary end punching plate is greater than the distance between the fourth oil hole and the center of the secondary end punching plate; The angle between the symmetric center line of the third oil hole and the symmetric center line of the fourth oil hole is the first preset angle, the angle between the symmetric center line of the third oil hole and the symmetric center line of the fourth welding groove adjacent to it is the third preset angle, and the angle between the symmetric center line of the fourth oil hole and the symmetric center line of the fourth welding groove adjacent to it is the third preset angle.
5. The oil-cooled stator core according to claim 4, characterized in that: The distance between the first welding groove and the center of the main body punching sheet, the distance between the second welding groove and the center of the main end punching sheet, the distance between the third welding groove and the center of the main end punching sheet, and the distance between the fourth welding groove and the center of the secondary end punching sheet are all equal; The maximum outer diameters of the main punching sheet, the main end punching sheet and the secondary end punching sheet are equal; The inner diameters of the main punching sheet, the main end punching sheet and the secondary end punching sheet are equal; The first welding groove, the second welding groove, the third welding groove and the fourth welding groove have the same shape and the same size.
6. The oil-cooled stator core according to claim 4, characterized in that: Part of the first welding groove on the main lamination stack and part of the second welding groove on the first end lamination stack are connected and welded to each other; Part of the first welding groove on the main lamination stack and part of the third welding groove on the first end lamination stack are connected and welded to each other; or Part of the first welding groove on the main lamination stack and part of the second welding groove and part of the third welding groove on the first end lamination stack are connected and welded and fixed.
7. The oil-cooled stator core according to claim 4, characterized in that: A portion of the second welding groove on the first end lamination and a portion of the fourth welding groove on the second end lamination group are connected and welded and fixed; Part of the third welding groove on the first end lamination and part of the fourth welding groove on the second end lamination group are connected and welded and fixed; Part of the second welding groove, part of the third welding groove on the first end lamination and part of the fourth welding groove on the second end lamination group are connected and welded and fixed.
8. The oil-cooled stator core according to claim 4, characterized in that: The symmetric center line of the step coincides with the symmetric center line of the first core slot or stator tooth on the inner side of the main body punching sheet; The symmetric center line of the first oil hole and the symmetric center line of the second oil hole respectively coincide with the symmetric center line of the second core slot or the stator tooth inside the main end punching sheet; The symmetric center line of the third oil hole and the symmetric center line of the fourth oil hole coincide with the symmetric center line of the third core slot or the stator tooth on the inner side of the secondary end punching sheet respectively.
9. An oil-cooled drive motor, characterized in that: It comprises the oil-cooled stator core as described in any one of claims 1 to 8.