Stator core, stator, motor, power assembly and vehicle

Abstract

The invention discloses a stator core, a stator, a motor, a power assembly and a vehicle, the stator core comprises a plurality of stator punching sheet groups, the plurality of stator punching sheet groups are laminated along the axial direction of the stator core, and each stator punching sheet group comprises a plurality of stator punching sheets laminated along the axial direction of the stator core; wherein the size of the stator punching sheet group along the axial direction of the stator core is L2, the number of welding spots between two adjacent stator punching sheet groups is N, the size of the welding spots along the axial direction of the stator core is L1, the outer diameter of the stator punching sheet is R, and L1, L2, N and R meet the relational expression that L1 / L2 is greater than or equal to 0.12 and less than or equal to 0.6, and N / R is greater than or equal to 0.026 and less than or equal to 0.043. Therefore, by designing the stator iron core, iron loss deterioration caused by traditional integral welding can be reduced on the basis of satisfying the binding force between the stator punching sheets, so that the structural firmness of the stator iron core and the motor efficiency are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of vehicles, and in particular to a stator core, a stator, a motor, a power assembly and a vehicle. Background Art

[0002] The motor stator is a key component of the motor. It is an important flow path for the air gap magnetic flux. It also plays an important role in fixing the armature winding to convert electrical energy into mechanical energy through armature reaction. Electric vehicles have high requirements for various indicators such as torque, power, efficiency, NVH performance and cost when using drive motors. How to innovate the design and manufacturing process of new energy drive motor stators while taking into account performance and cost has always been a research hotspot in the industry.

[0003] In the related technology, the traditional motor stator forming process includes riveting, welding, riveting + overall welding, but each process has its own shortcomings. Riveting is only suitable for smaller motors because of the weak bonding force between the iron core punching sheets. Welding and riveting + overall welding will cause large-area ablation of the motor stator insulation layer, increase the iron loss of the motor stator and affect the motor efficiency. Summary of the invention

[0004] The present invention aims to solve at least one of the technical problems existing in the prior art. To this end, one object of the present invention is to provide a stator core which can reduce the deterioration of iron loss caused by traditional integral welding while satisfying the bonding force between stator punching sheets.

[0005] The present invention further provides a stator.

[0006] The present invention further provides a motor.

[0007] The present invention further provides a power assembly.

[0008] The present invention further provides a vehicle.

[0009] According to the first aspect of the present invention, the stator core comprises: a plurality of stator punching sheet groups, the plurality of stator punching sheet groups are stacked along the axial direction of the stator core, and the stator punching sheet groups include a plurality of stator punching sheets stacked along the axial direction of the stator core; wherein, the dimension of the stator punching sheet group along the axial direction of the stator core is L2, the number of welding points between two adjacent stator punching sheet groups is N, the dimension of the welding points along the axial direction of the stator core is L1, the outer diameter of the stator punching sheet is R, and L1, L2, N and R satisfy the relationship: 0.12≤L1 / L2≤0.6, and 0.026≤N / R≤0.043.

[0010] Therefore, by designing the stator core, it is possible to reduce the iron loss deterioration caused by traditional integral welding while satisfying the bonding force between the stator punching sheets, thereby improving the structural firmness of the stator core and the motor efficiency.

[0011] In some examples of the present invention, L1 and L2 satisfy the relationship: 0.4≤L1 / L2≤0.5.

[0012] In some examples of the present invention, N and R satisfy the relationship: 0.028≤N / R≤0.035.

[0013] In some examples of the present invention, L1 satisfies the relationship: 3mm≤L1≤6mm.

[0014] In some examples of the present invention, L2 satisfies the relationship: 10 mm ≤ L2 ≤ 25 mm.

[0015] In some examples of the present invention, N satisfies the relationship: 6≤N≤8.

[0016] In some examples of the present invention, R satisfies the relationship: 160 mm ≤ R ≤ 230 mm.

[0017] In some examples of the present invention, the N welding points between two adjacent stator sheet groups are evenly distributed in the circumferential direction of the stator sheet group.

[0018] In some examples of the present invention, a plurality of weld grooves are provided on the outer peripheral surface of the stator punching group, the plurality of weld grooves extend along the axial direction of the stator core and are spaced apart in the circumferential direction of the stator punching group, and the N welding points between two adjacent stator punching groups are respectively provided in the plurality of weld grooves.

[0019] In some examples of the present invention, the plurality of weld grooves are evenly distributed in the circumferential direction of the stator sheet group.

[0020] In some examples of the present invention, a convex rib protruding toward the groove opening is formed at the groove bottom of the weld groove, and the welding point is arranged on the convex rib.

[0021] In some examples of the present invention, the thickness of the stator punching sheet is D, and H and D satisfy the relationship: L1≥5D.

[0022] In some examples of the present invention, the total number of the welding points of the stator core is N 总 The axial dimensions of the stator core are L, N 总 Satisfy the relationship: 24≤N 总 =N×L / L2≤80.

[0023] In some examples of the present invention, the number of the welding points between at least two of the stator punching sheet groups and the adjacent stator punching sheet groups is different.

[0024] In some examples of the present invention, the total number of the welding points of the stator core is N 总 The theoretical number of welding points between two adjacent stator punching groups is In the direction extending from one axial end to the other axial end of the stator core, the number of the welding points between two adjacent stator punching groups is , , ,……, , the number of stator punching groups is K; wherein, N 总 = ; 24≤N 总 ≤80.

[0025] A stator according to a second aspect of the present invention comprises: the above-mentioned stator core.

[0026] A motor according to a third aspect of the present invention comprises: the above-mentioned stator.

[0027] A powertrain according to a fourth aspect of the present invention comprises: the above-mentioned motor.

[0028] A vehicle according to a fifth aspect of the present invention comprises: the above-mentioned powertrain.

[0029] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The above and / or additional aspects and advantages of the present invention will become apparent and easily understood from the description of the embodiments in conjunction with the following drawings, in which: Figure 1 is a schematic structural diagram of a stator core according to an embodiment of the present invention; Figure 2 is a schematic structural diagram of a stator core according to another embodiment of the present invention; Figure 3 is a side view of a stator core according to an embodiment of the present invention; Figure 4 yes Figure 3 A magnified image of area A; Figure 5 is a front view of a stator punching group according to an embodiment of the present invention; Figure 6 is a front view of a stator punching group according to another embodiment of the present invention; Figure 7is a front view of a stator punching group according to another embodiment of the present invention; Figure 8 Schematic diagram of an assembly according to an embodiment of the present invention.

[0031] Reference numerals: 100. stator core; 10. Stator punching sheet group; 11. Welding groove; 111. Raised rib; 12. Stator punching sheet; 13. Rivet buckle; 14. Welding point. DETAILED DESCRIPTION

[0032] Embodiments of the present invention are described in detail below. The embodiments described with reference to the accompanying drawings are exemplary. Embodiments of the present invention are described in detail below.

[0033] Reference below Figure 1-Figure 8 The stator core 100 according to the embodiment of the present invention can ensure the production cycle of the stator core 100 and reduce the iron loss deterioration caused by traditional integral welding, thereby taking into account both production efficiency and motor efficiency.

[0034] Combination Figure 1-Figure 8 As shown, the stator core 100 according to the first embodiment of the present invention includes a plurality of stator sheet groups 10. The plurality of stator sheet groups 10 are stacked together in a specific manner to form a complete stator core 100, and in order to ensure the uniformity of the magnetic field, the stator sheet groups 10 need to be precisely aligned, thereby improving the overall performance of the motor; and by assembling the stator sheet groups 10 in batches, it is easy to assemble and improve the production cycle.

[0035] Specifically, a plurality of stator sheet groups 10 are stacked along the axial direction of the stator core 100 , and the stator sheet group 10 includes a plurality of stator sheet groups 12 stacked along the axial direction of the stator core 100 , and welding points 14 for connection are provided between two adjacent stator sheet groups 10 .

[0036] Specifically, each stator punching group 10 is composed of a plurality of stator punchings 12 stacked along the axial direction of the stator core 100. Adjacent stator punchings 12 can be connected together by riveting first, and then two adjacent stator punching groups 10 are connected together by welding. Compared with the conventional integrally welded stator core (that is, adjacent stator punchings are connected by welding), the embodiment in this case first rivets some stator punchings 12 into a stator punching group 10, and then welds adjacent stator punching groups 10 to each other. In this way, the insulation layer of each stator punching 12 can be prevented from being burned in a large area due to the welding process, thereby reducing the risk of deterioration of the iron loss of the stator core 100, thereby improving the efficiency of the motor. Compared with the conventional method of connecting adjacent stator punchings by gluing, the embodiment in this case has a faster production cycle and lower production cost.

[0037] In particular, the dimension of the stator sheet group 10 along the axial direction of the stator core 100 is L2, the number of the welding points 14 between two adjacent stator sheet groups 10 is N, the dimension of the welding points 14 along the axial direction of the stator core 100 is L1, the outer diameter of the stator sheet 12 is R, and L1, L2, N and R satisfy the relationship: 0.12≤L1 / L2≤0.6, and 0.026≤N / R≤0.043. Among them, the outer diameter of the stator sheet 12 is also the diameter of the stator sheet 12, and the above parameter relationship of L1 / L2 and N / R is verified by experiments to obtain empirical data (as shown in Table 1).

[0038] Table 1

[0039] By comparing the above data, the following conclusion can be drawn: when the ratio of the size of the welding spot 14 along the axial direction of the stator core 100 to the size of the stator sheet group 10 along the axial direction of the stator core 100 is within the range of 0.12-0.6, and the ratio of the number of welding spots 14 between two adjacent stator sheet groups 10 to the outer diameter of the stator sheet 12 is within the range of 0.026-0.043, the stator core 100 can reduce the number of welding spots 14 and reduce the iron loss ratio of the motor on the basis of satisfying the bonding force (that is, the pulling force) between the stator sheets 12, thereby taking into account both the firmness of the stator core 100 and the efficiency of the motor. For example, L1 / L2 can be 0.12, 0.2, 0.3, 0.5 and 0.6, etc., but not limited thereto; N / R can be 0.026, 0.03, 0.035 and 0.043, etc., but not limited thereto.

[0040] Therefore, by designing the stator core 100 , it is possible to reduce the iron loss deterioration caused by traditional integral welding while satisfying the bonding force between the stator punching sheets 12 , thereby improving the structural firmness of the stator core 100 and the motor efficiency.

[0041] Preferably, L1 and L2 satisfy the relationship: 0.4≤L1 / L2≤0.5. When the ratio between the size of the welding spot 14 along the axial direction of the stator core 100 and the size of the stator sheet group 10 along the axial direction of the stator core 100 is within the range of 0.4-0.5, the size of the welding spot 14 along the axial direction of the stator core 100 is closer to or equal to half of the size of the stator sheet group 10 along the axial direction of the stator core 100, so that the size of the welding spot 14 along the axial direction of the stator core 100 can be relatively increased, thereby increasing the welding area between the welding spot 14 and the stator sheet group 10 while reducing the deterioration of iron loss, and better improving the connection firmness between the stator sheet groups 10. For example, L1 / L2 can be 0.4, 0.45, 0.5, etc., but is not limited thereto.

[0042] Another preferred embodiment is that N and R satisfy the relationship: 0.028≤N / R≤0.035. Among them, when the ratio between the number of welds 14 between two adjacent stator sheet groups 10 and the outer diameter of the stator sheet 12 is in the range of 0.028-0.035, the number of welds 14 between two adjacent stator sheet groups 10 is relatively less, so that the number of welds 14 can be reduced on the basis of satisfying the bonding force between the stator sheet groups 10, thereby better reducing the iron loss ratio and improving the motor efficiency. For example, N / R can be 0.028, 0.3, 0.035, etc., but is not limited thereto.

[0043] In another preferred embodiment, L1 satisfies the relationship: 3mm≤L1≤6mm. The size of the welding spot 14 along the axial direction of the stator core 100 is limited within a reasonable range. On the one hand, it can ensure the welding contact area that meets the connection strength between the stator punching group 10, and on the other hand, it can avoid taking up too much extra space and reduce the iron loss ratio of the stator core 100, thereby taking into account both the firmness of the stator core 100 and the motor efficiency. For example, the size of the welding spot 14 along the axial direction of the stator core 100 can be 3mm, 4mm, 5mm, 6mm, etc., but is not limited thereto.

[0044] In another preferred embodiment, L2 satisfies the relationship: 10mm≤L2≤25mm. The size of the stator sheet group 10 along the axial direction of the stator core 100 is limited within a reasonable range, so that the risk of insufficient bonding force (riveting) of the stator sheets 12 in the same section of the stator sheet group 10 due to the excessive axial size of the stator sheet group 10 can be avoided, thereby improving the structural reliability of the stator core 100. For example, the size of the stator sheet group 10 along the axial direction of the stator core 100 can be 10mm, 12mm, 15mm, 18mm and 20mm, but is not limited thereto.

[0045] In another preferred embodiment, N satisfies the relationship: 6≤N≤8. The number of welds 14 between two adjacent stator sheet groups 10 is limited within a reasonable range, so that the connection stress can be more evenly distributed on multiple welds 14 while ensuring the connection strength between two adjacent stator sheet groups 10, avoiding the risk of local stress concentration, and reducing the number of unnecessary welds 14 as much as possible, thereby reducing the iron loss ratio, and further improving the firmness of the electronic core and the efficiency of the motor. For example, the number of welds 14 between two adjacent stator sheet groups 10 can be 6, 7 or 8.

[0046] In another preferred embodiment, R satisfies the relationship: 160mm≤R≤230mm. Among them, the outer diameter of the stator punching sheet 12 is limited within a reasonable range, so that the outer diameter of the stator punching sheet 12 can be larger, which makes it easier for the stator core 100 to accommodate more windings, thereby improving the electromagnetic conversion efficiency of the motor, and avoiding the risk of a decrease in magnetic flux density due to its oversized size. It also helps to control the eddy current path length, reduce eddy current losses, and improve the overall efficiency of the motor. Moreover, the larger outer diameter size of the stator punching sheet 12 can expand the surface area of ​​the stator core 100 without increasing the thickness, which is beneficial to the dissipation of heat and improves the thermal management effect of the motor. For example, the outer diameter of the stator punching sheet 12 can be 160mm, 180mm, 200mm, 210mm and 230mm, but is not limited to this.

[0047] According to some optional embodiments of the present invention, Figure 3 , Figure 4-Figure 7 As shown, the N welding spots 14 between two adjacent stator lamination groups 10 are evenly distributed in the circumferential direction of the stator lamination group 10 .

[0048] Arranged as above, N welding points 14 can be uniformly stressed between two adjacent stator sheet groups 10 along the circumference of the stator core 100, avoiding the problem of local stress concentration, which is conducive to extending the service life of the stator core 100 and reducing damage caused by local fatigue. It can also prevent the risk of warping or bending in the local area due to the lack of sufficient fixing points, thereby ensuring the overall flatness of the stator core 100; and the evenly distributed welding points 14 can keep the magnetic flux path of the stator core 100 consistent, reduce magnetic field distortion, thereby improving the efficiency and performance of the motor, and can also avoid forming a larger closed loop, thereby reducing eddy current losses; the evenly distributed welding points 14 can also form more heat conduction paths on the entire stator core 100, promote uniform diffusion of heat, and reduce the risk of local overheating. In addition, during the stacking process of the stator sheet group 10, the evenly distributed welding points 14 or connection points can help operators more easily align each section of the stator sheet group 10, ensure that they are consistent in both radial and axial directions, and help improve assembly accuracy and reduce error accumulation.

[0049] According to some optional embodiments of the present invention, Figure 1-Figure 4 As shown, the outer circumferential surface of the N stator punching sheet groups 10 is provided with a plurality of weld slots 11, the plurality of weld slots 11 extend along the axial direction of the stator core 100, and the plurality of weld slots 11 are distributed at intervals on the outer circumference of the stator punching sheet groups 10, and the N welding points between two adjacent stator punching sheet groups 10 are respectively arranged in the plurality of weld slots 11.

[0050] Among them, the weld groove 11 can reserve welding space for the weld spot 14, increase the welding contact area between the weld spot 14 and the stator sheet group 10, improve the welding strength, and prevent the weld spot 14 from protruding from the outer peripheral edge of the stator sheet group 10, thereby affecting the surface flatness of the stator sheet group 10 in its own circumferential direction, reducing eddy current loss, and ensuring the performance of the motor. Moreover, the N weld spots 14 between two adjacent stator sheet groups 10 are respectively arranged in a plurality of weld grooves 11, so that the uniformity of the force distribution of the weld spot 14 in the circumferential direction of the stator sheet group 10 can be improved, thereby ensuring its service life, and the weld spots 14 are uniformly arranged in the weld grooves 11, which is conducive to improving the regularity of the weld spots 14.

[0051] Specifically, combined Figure 5-Figure 7 As shown, a plurality of weld slots 11 are evenly distributed in the circumferential direction of the stator punching sheet group 10. Such an arrangement can effectively disperse mechanical stress, avoid local stress concentration, and improve force uniformity; it can also help to balance the mass distribution of the stator core 100, reduce the vibration during motor operation, thereby reducing noise and extending service life; and the evenly distributed design is conducive to making the stator core 100 achieve a smoother rotational motion, avoid additional stress and wear caused by imbalance, and can also facilitate the operation of automated production equipment, simplify the production process, and improve production efficiency and consistency.

[0052] Furthermore, combined with Figure 1 , Figure 2 and Figure 5 As shown, the bottom of the weld groove 11 is formed with a convex rib 111 protruding toward the groove, and the weld point 14 is arranged on the convex rib 111. Among them, the convex rib 111 can increase the actual contact area of ​​the welding surface, and the welding material can better fill and wrap the contact surface, thereby improving the welding strength of the weld point 14; in addition, the convex rib 111 can guide the flow of welding materials, reduce the pores and cracks generated during the welding process, and improve the quality of the weld. The convex rib 111 can also provide more metal materials for fusion, making the weld joint tighter, reducing the possibility of welding defects, thereby improving the welding fusion effect, and then improving the welding quality. For example, the structure of the weld groove 11 is similar to a "W" shape, but is not limited to this.

[0053] Specifically, combined Figure 1 and Figure 3As shown, since the stator punching sheet group 10 is stacked and connected along the axial direction of the stator core 100, the weld points 14 in at least one weld slot 11 are evenly distributed along the axial direction of the stator core 100. Such an arrangement can make the axial connection stress distribution of multiple stator punching sheet groups 10 more uniform, avoid the problem of local stress concentration, and thus improve the force uniformity of the weld points 14 in the axial direction of the stator core 100.

[0054] Furthermore, combined with Figure 1 and Figure 2 As shown, the number of welding points 14 in two adjacent welding slots 11 is different. Such an arrangement can flexibly reduce the number of welding points 14 on the basis of ensuring the connection strength between the stator punching groups 10, reduce the risk of ablation of the insulation layer of the stator punching 12, reduce the stator iron loss, and thus improve the efficiency of the motor. For example, the number of welding points 14 in one welding slot 11 is 5, and the number of welding points 14 in another welding slot 11 is 2 (such as Figure 1 ); For another example, the number of weld points 14 in one weld slot 11 is 2, and the number of weld points 14 in another weld slot 11 is 3 (e.g. Figure 2 ) etc., but not limited to these.

[0055] Specifically, combined Figure 2 As shown, the welding points 14 in two adjacent welding grooves 11 are staggered along the axial direction of the stator core 100. The above arrangement can enable different stator punching groups 10 to form an effect of mutual connection in the axial direction of the stator core 100, and can also enable different stator punching groups 10 to form a connection relationship at different positions in the circumferential direction, thereby taking into account the connection effects between different stator punching groups 10 in the axial and circumferential directions at the same time, and can also effectively reduce the number of welding points 14, reduce the risk of ablation of the insulation layer of the stator punching layer 12, reduce the stator iron loss, and thus improve the efficiency of the motor.

[0056] According to some optional embodiments of the present invention, Figure 4As shown, the size of the welding spot 14 along the axial direction of the stator core 100 is L1, the thickness of the stator punching sheet 12 is D, L1 and D satisfy the relationship: L1 ≥ 5D, the welding spot 14 has a larger size along the axial direction of the stator core 100, so as to provide a larger contact area, enhance the connection strength between the welding spot 14 and the stator punching sheet 12, and prevent the welding spot 14 from loosening or falling off due to vibration or mechanical stress during the operation of the motor, thereby improving the connection firmness between the stator punching sheet group 10; the larger size of the welding spot 14 can better separate the stator punching sheet group 10. The larger size of the weld spot 14 can provide a stronger support force in the axial direction of the stator core 100, reduce the warping and bending caused by external loads or internal stress, and ensure the overall flatness and rigidity of the stator core 100; the larger size of the weld spot 14 can provide more heat conduction paths, help transfer heat from the heat-generating parts (such as windings) to the external environment, help reduce the risk of local overheating, and improve the heat dissipation effect of the motor.

[0057] For example, the thickness of the stator punching sheet 12 is 0.2 mm, 0.3 mm, etc., and the size of the welding point 14 along the axial direction of the stator core 100 is 1 mm, 1.5 mm, etc., but it is not limited thereto.

[0058] According to some optional embodiments of the present invention, the total number of welding points 14 of the stator core 100 is N. 总 , the axial dimensions of the stator core 100 are L, N 总 Satisfy the relationship: 24≤N 总 =N×L / L2≤80. The above parameter relationship is obtained by experimental verification and empirical data.

[0059] It can be understood that the above relationship can be used to obtain N 总 The total number of welding points in the stator core 100 can be obtained by using the value of N 总 The values ​​of N, L and L2 can be flexibly selected according to design requirements (when two values ​​are known, the value range of another unknown parameter is determined). The stator core 100 designed in this way can take into account both the firmness of the stator core 100 and the motor efficiency. 总 It can be 24, 30, 50, 60, 80, etc., but is not limited thereto.

[0060] According to some optional embodiments of the present invention, the number of welds 14 between at least two stator punching groups 10 and adjacent stator punching groups 10 is different. With such an arrangement, the number of welds 14 can be flexibly reduced on the basis of ensuring the connection strength between the stator punching groups 10, thereby reducing the risk of ablation of the insulation layer of the stator punching layers 12 and reducing the stator iron loss, thereby improving the efficiency of the motor.

[0061] According to some optional embodiments of the present invention, the total number of welding points 14 of the stator core 100 is N. 总 The theoretical number of welding points 14 between two adjacent stator punching groups 10 is In the direction extending from one axial end to the other axial end of the stator core 100, the number of welding points 14 between two adjacent stator punching sheet groups 10 is , , ,……, , the number of stator punching group 10 is K; wherein, N 总 = ; 24≤N 总 ≤80. The parameter relationship is obtained by experimental verification and empirical data.

[0062] It can be understood that the above relationship can make N 总 , R, L and N establish parameter connections, when N 总 When the number of welding points 14 is less than the minimum value of 24, the number of welding points 14 cannot meet the strength requirement of fixing the stator core 100. 总 When the value is greater than the maximum value of 80, the number of welding spots 14 is too large, which will increase the iron loss of the motor and reduce the efficiency of the motor.

[0063] In addition, the above parameter relationship can be used to flexibly select the values ​​of R, L and N according to design requirements (when two values ​​are known, the value range of another unknown parameter is determined). The stator core 100 designed in this way can take into account both the firmness of the stator core 100 and the motor efficiency. For example, N 总 It can be 24, 30, 50, 60, 80, etc., but is not limited thereto.

[0064] According to some optional embodiments of the present invention, Figure 4-Figure 7 As shown, the multiple stator punching sheets 12 in each stator punching sheet group 10 are provided with rivet buckles 13 for connection. In the manufacturing process of the stator core 100, the multiple stator punching sheets 12 in each stator punching sheet group 10 are usually provided with rivet buckles 13 for connection. The rivet buckles 13 and the corresponding rivets are used to firmly rivet the multiple stator punching sheets 12 together to form an integral stator core 100. For example, rivet buckles are used when the stator punching sheets 12 are stacked, and the number of rivet buckles can be set to 8, 10, 12, 16, 18, 20, etc. as needed. The specific number is determined according to the stator size and the number of motor poles, and is generally greater than or equal to 8, so as to ensure the pull-out force requirement of the stator core 100 after riveting.

[0065] The above-mentioned riveted connection can effectively prevent the stator punching sheets 12 from loosening or shifting during operation, ensure the overall structural stability and mechanical strength of the stator core 100, and the stator core 100 after riveting has higher rigidity and vibration resistance, and can maintain good performance under high speed and high load conditions; rivets can increase the contact area between the stator punching sheets 12, reduce contact resistance, and help improve the heat dissipation performance of the motor and reduce temperature rise; and a reasonably designed layout of the rivet buckles 13 can leave a tiny gap between the stator punching sheets 12, promote air circulation, and further enhance the heat dissipation effect.

[0066] Optionally, the rivets 13 are usually distributed on the outer edge or specific internal positions of the stator punching sheets 12 (for example, evenly distributed along the circumference or concentrated in key stress-bearing areas) to ensure that the entire stator punching sheet group 10 can obtain uniform fixing force in all directions; depending on the size of the stator core 100 and application requirements, each stator punching sheet group 10 may include multiple rivets 13, and larger motors usually require more rivets 13 to provide sufficient fixing force.

[0067] In addition, the process of riveting different stator punching sheets 12 to each other is introduced. First, multiple stator punching sheets 12 are accurately stacked together according to the design requirements to ensure that each stator punching sheet 12 is aligned and the interlayer insulation is maintained; rivets are inserted into the stacked stator punching sheet group 10 to ensure that each rivet hole has a corresponding rivet; special riveting equipment (such as a hydraulic riveting machine or a pneumatic riveting pliers) is used to hammer or press the rivet so that its head is deformed and tightly combined with the punching sheet. For the stator punching sheet 12 with a raised structure, the rivet head can be directly formed by pressing.

[0068] According to some optional embodiments of the present invention, a plurality of stator punching sheets 12 in each stator punching sheet group 10 are provided with adhesive for connection, and the adhesive is structured in a layered or dispersed dot shape.

[0069] Specifically, the multiple stator punching sheets 12 in each stator punching sheet group 10 are firmly bonded together by adhesive, which can effectively improve the overall rigidity and vibration resistance of the stator punching sheet group 10, and prevent the stator punching sheets 12 from loosening or shifting during operation. Moreover, the adhesive will not introduce additional metal materials, so it will not form a larger closed loop, which is conducive to maintaining the consistency of the magnetic flux path of the stator core 100, reducing magnetic field distortion, and improving the efficiency and performance of the motor.

[0070] Optionally, combined Figure 5As shown, the weld grooves 11 and the rivets 13 are spaced apart in the circumferential direction of the stator punching group 10, so as to increase the force transmission path between the stator punching groups 10 in the circumferential direction, thereby enhancing the force uniformity of the stator core 100 in its own circumferential direction, reducing the risk of local stress concentration, and thus improving the structural firmness of the stator core 100.

[0071] Alternatively, combining Figure 6 As shown, along the circumference of the stator punching group 10, the number of rivet buckles 13 between adjacent weld slots 11 is different. In this way, while ensuring the firm connection between the stator punching groups 10, the number of rivet buckles 13 can be flexibly adjusted according to needs, thereby reducing eddy current losses and improving motor performance.

[0072] The stator according to the second aspect of the present invention includes the stator core 100 of the above embodiment. The stator with the stator core 100 can reduce the large-area ablation problem caused by the welding process while ensuring its own firmness, and can also improve the production cycle.

[0073] Combination Figure 8 As shown, the production process of the stator core 100 is described in detail below: first, a single stator punching sheet 12 is punched out using a stamping die, and then the stator punching sheet 12 is stacked along the axial direction to obtain a stator punching sheet group 10 that meets the size requirements, and then each stator punching sheet group 10 is assembled using a tool, and each stator punching sheet group 10 is welded together using spot welding at the connection between the stator punching sheet groups 10 to obtain the entire stator core 100. In this way, the iron loss deterioration caused by traditional integral welding can be reduced, the motor efficiency can be improved, and the motor manufacturing cost can be reduced.

[0074] The stator core 100 is a fixed part of a motor (such as an AC motor, a DC motor, a synchronous motor, and an asynchronous motor), and is usually located inside the motor housing. It is stacked with a plurality of thin silicon steel sheets (i.e., stator punching sheets 12), which are stacked and fixed together to form an integral structure. In addition, each stator punching sheet 12 has a tooth slot structure, the teeth are used to support the winding, and the slots are used to accommodate the winding coils. The three-phase winding is installed in the slots of the stator punching sheet 12, and a rotating magnetic field is generated by current. The stator punching sheets 12 and the windings and the stator punching sheets 12 need to be insulated to prevent the occurrence of eddy currents and short circuits.

[0075] The motor according to the third aspect of the present invention includes the stator of the above embodiment, so the motor with the stator can improve the working efficiency and reduce the manufacturing cost of the motor.

[0076] The powertrain according to the fourth aspect of the present invention includes the motor of the above-mentioned embodiment. The powertrain with the motor can improve driving stability and working efficiency, thereby improving reliability.

[0077] The vehicle according to the fifth aspect of the present invention includes the powertrain of the above-mentioned embodiment. A vehicle having the powertrain can improve cruising range and reduce the manufacturing cost of the whole vehicle, thereby improving the market competitiveness of the vehicle.

[0078] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "axial", "radial", "circumferential" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as limiting the present invention.

[0079] In the description of this application, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0080] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0081] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

[0082] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "illustrative embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example.

[0083] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the claims and their equivalents.

Claims

1. A stator core, characterized in that: include: A plurality of stator punching sheet groups, wherein the plurality of stator punching sheet groups are stacked along the axial direction of the stator core, and the stator punching sheet group comprises a plurality of stator punching sheets stacked along the axial direction of the stator core; The dimension of the stator sheet group along the axial direction of the stator core is L2, the number of welding points between two adjacent stator sheet groups is N, the dimension of the welding points along the axial direction of the stator core is L1, the outer diameter of the stator sheet is R, and L1, L2, N and R satisfy the relationship: 0.12≤L1 / L2≤0.6, and 0.026≤N / R≤0.

043.

2. The stator core according to claim 1, characterized in that: L1 and L2 satisfy the relationship: 0.4≤L1 / L2≤0.

5.

3. The stator core according to claim 1, characterized in that: N and R satisfy the relationship: 0.028≤N / R≤0.

035.

4. The stator core according to claim 1, characterized in that: L1 satisfies the relationship: 3mm≤L1≤6mm.

5. The stator core according to claim 1, characterized in that: L2 satisfies the relationship: 10mm≤L2≤25mm.

6. The stator core according to claim 1, characterized in that: N satisfies the relationship: 6≤N≤8。 7. The stator core according to claim 1, characterized in that: R satisfies the relationship: 160mm≤R≤230mm.

8. The stator core according to claim 1, characterized in that: The N welding spots between two adjacent stator sheet groups are evenly distributed in the circumferential direction of the stator sheet group.

9. The stator core according to claim 1, characterized in that: The outer peripheral surface of the stator punching group is provided with a plurality of weld grooves, which extend along the axial direction of the stator core and are spaced apart in the circumferential direction of the stator punching group, and the N welding points between two adjacent stator punching groups are respectively arranged in the plurality of weld grooves.

10. The stator core according to claim 9, characterized in that: The plurality of weld grooves are evenly distributed in the circumferential direction of the stator sheet group.

11. The stator core according to claim 9, characterized in that: A convex rib protruding toward the groove opening is formed at the groove bottom of the weld groove, and the welding point is arranged on the convex rib.

12. The stator core according to claim 1, characterized in that: The thickness of the stator punching sheet is D, and L1 and D satisfy the relationship: L1≥5D.

13. The stator core according to claim 1, characterized in that: The total number of the welding points of the stator core is N 总 The axial dimensions of the stator core are L, N 总 Satisfies the relationship: 24≤N 总 =N×L / L2≤80。 14. The stator core according to claim 1, characterized in that: The number of the welding points between at least two of the stator punching sheet groups and the adjacent stator punching sheet groups is different.

15. The stator core according to claim 1, characterized in that: The total number of the welding points of the stator core is N 总 The theoretical number of welding points between two adjacent stator punching groups is In the direction extending from one axial end to the other axial end of the stator core, the number of the welding points between two adjacent stator punching groups is , , ,……, , the number of the stator punching group is K; in, N 总 = ； 24≤N 总 ≤80。 16. A stator, characterized in that: include: The stator core according to any one of claims 1 to 15.

17. A motor, characterized in that: include: The stator as claimed in claim 16.

18. A powertrain, characterized in that: include: The motor of claim 17.

19. A vehicle, characterized in that: include: The powertrain of claim 18.

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