Rotor lamination, rotor assembly, electric motor, electric drive assembly and vehicle

WO2026194482A1PCT designated stage Publication Date: 2026-09-24BYD CO LTD
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Patent Information

Application Number
PCT/CN2026/074826
Authority / Receiving Office
WO · WO
Patent Type
Applications
Current Assignee / Owner
Priority Date
2025-03-17
Filing Date
2026-01-26
Publication Date
2026-09-24

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  • Figure CN2026074826_24092026_PF_FP_ABST
    Figure CN2026074826_24092026_PF_FP_ABST
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Abstract

A rotor lamination, a rotor assembly, an electric motor, an electric drive assembly, and a vehicle. The rotor lamination comprises: a lamination body. The lamination body is provided with a plurality of mounting regions arranged at intervals in the circumferential direction, first magnet slot sets being formed in the mounting regions. Each first magnet slot set comprises: a first magnet slot and a second magnet slot which are adjacent in the circumferential direction of the lamination body and are arranged at an included angle; the first magnet slot comprises a first accommodating slot and a first buffer slot, the first buffer slot being connected to the end of the first accommodating slot facing the second magnet slot, and the first buffer slot being arranged on the inner side of the first accommodating slot in the radial direction of the lamination body; the second magnet slot comprises: a second accommodating slot and a second buffer slot, the second buffer slot being connected to the end of the second accommodating slot facing the first magnet slot, and the second buffer slot being arranged on the outer side of the second accommodating slot in the radial direction of the lamination body.
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Description

Rotor laminations, rotor assemblies, motors, electric assemblies, and vehicles

[0001] Cross-references to related applications

[0002] This application is based on and claims priority to Chinese Patent Application No. 2025103184293, filed on March 17, 2025, the entire contents of which are incorporated herein by reference. Technical Field

[0003] This application relates to the field of vehicle technology, and in particular to a rotor lamination, rotor assembly, motor, electric assembly, and vehicle. Background Technology

[0004] During the operation of the motor, under ultra-high speed conditions, the rotor core will experience significant stress concentration at the magnetic bridge, reinforcing ribs, and support arms. If the stress in these areas exceeds the allowable stress of the rotor core material, the rotor core may be at risk of fracture failure after long-term operation.

[0005] Application content

[0006] This application aims to at least solve one of the technical problems existing in the prior art. To this end, this application proposes a rotor lamination that can extend the stress on the reinforcing ribs in two opposite directions, thereby reducing stress concentration when the reinforcing ribs are under stress, thus reducing the risk of the rotor lamination being crushed and improving the reliability of the motor during operation.

[0007] This application also proposes a rotor assembly having the aforementioned rotor laminations.

[0008] This application also proposes an electric motor having the above-described rotor assembly.

[0009] This application also proposes an electric assembly having the aforementioned motor.

[0010] This application also proposes a vehicle having the aforementioned motor or electric assembly.

[0011] According to a first aspect of this application, the rotor lamination includes: a lamination body, the lamination body having a plurality of mounting areas arranged circumferentially at intervals, each mounting area forming a first magnet slot group, the first magnet slot group including: a first magnet slot and a second magnet slot arranged adjacent to each other and at an included angle in the circumferential direction of the lamination body, the first magnet slot including: a first receiving slot and a first buffer slot, the first buffer slot being connected to one end of the first receiving slot facing the second magnet slot, the first buffer slot being arranged inside the first receiving slot in the radial direction of the lamination body, the second magnet slot including: a second receiving slot and a second buffer slot, the second buffer slot being connected to one end of the second receiving slot facing the first magnet slot, the second buffer slot being arranged outside the second receiving slot in the radial direction of the lamination body.

[0012] According to the rotor lamination of this application, by setting a first buffer groove inside the first receiving groove in the radial direction of the lamination body and a second buffer groove outside the second receiving groove in the radial direction of the lamination body, the stress on the reinforcing rib can be extended in two opposite directions, thereby reducing the stress concentration when the reinforcing rib is under stress, thus reducing the risk of the rotor lamination being crushed and improving the reliability of the motor during operation.

[0013] According to one example of this application, the first buffer groove is formed by a recess in the inner wall of the end of the first receiving groove adjacent to the second receiving groove, and / or the second buffer groove is formed by a recess in the inner wall of the end of the second receiving groove adjacent to the first receiving groove.

[0014] According to one example of this application, in the circumferential direction of the lamination body, the first buffer groove extends obliquely toward the side opposite to the second magnet groove, and / or, the second buffer groove extends obliquely toward the side opposite to the first magnet groove.

[0015] According to one example of this application, the sidewall of the first buffer groove facing the second receiving groove is a first sidewall, and the first sidewall is formed as an arc surface protruding towards the second receiving groove, and / or, the sidewall of the second buffer groove facing the first receiving groove is a second sidewall, and the second sidewall is formed as an arc surface protruding towards the first receiving groove.

[0016] According to one example of this application, the sidewall of the first buffer groove facing the second receiving groove is a first sidewall, the sidewall of the first receiving groove facing the second receiving groove is a third sidewall, the third sidewall and the first sidewall together form an arc surface protruding towards the second receiving groove, and / or, the sidewall of the second buffer groove facing the first receiving groove is a second sidewall, the sidewall of the second receiving groove facing the first receiving groove is a fourth sidewall, the fourth sidewall and the second sidewall together form an arc surface protruding towards the first receiving groove.

[0017] According to one example of this application, in the radial direction from the inside to the outside of the lamination body, the first receiving groove extends obliquely toward a side opposite to the second receiving groove, and the second receiving groove extends circumferentially along the lamination body.

[0018] According to an example of this application, a first rib is formed between the first magnet groove and the second magnet groove. In the length direction of the first rib, the maximum distance between the first buffer groove and the second buffer groove is the length of the first rib. The ratio of the length of the first rib to the thickness of the first rib is 4.8 to 10.2.

[0019] According to one example of this application, a third buffer groove is connected to one end of the first receiving groove away from the first buffer groove, the third buffer groove being formed by a recess in the inner wall of the first receiving groove facing the periphery of the stamping body.

[0020] According to one example of this application, there are two first magnet slots, which are respectively disposed on both sides of a first center line, wherein the first center line is a straight line passing through the center of the lamination body and extending radially along the lamination body.

[0021] According to one example of this application, there are two second magnet slots, which are respectively located on both sides of the first center line and arranged between the two first magnet slots.

[0022] According to an example of this application, in the radial direction from the inside to the outside of the lamination body, the first receiving groove extends obliquely toward a side opposite to the second receiving groove, the second receiving groove extends circumferentially along the lamination body, and the length dimension of the first receiving groove in the extending direction is smaller than the length dimension of the second receiving groove in the extending direction.

[0023] According to one example of this application, a second rib is formed between the two second magnet slots, and the maximum distance between the two second magnet slots in the length direction of the second rib is the length of the second rib, and the ratio of the length of the second rib to the thickness of the second rib is 4.8-10.2.

[0024] According to one example of this application, the first magnet slot has a first pressure buffer slot connected to the side of the first receiving slot facing the edge of the lamination body, and the first pressure buffer slot is arranged at one end of the first receiving slot near the second receiving slot.

[0025] According to an example of this application, the mounting area is formed with a second magnet groove group, the second magnet groove group including at least one third magnet groove, the second magnet groove group and the first magnet groove group are arranged at a radial distance along the lamination body, and in the radial direction of the lamination body, the second magnet groove group is arranged outside the first magnet groove group.

[0026] According to an example of this application, there are two third magnet slots, which are respectively disposed on both sides of a first center line. The first center line is a straight line passing through the center of the lamination body and extending radially along the lamination body. In the radial direction of the lamination body from the inside to the outside, the two third magnet slots extend in opposite directions. Each of the two third magnet slots includes a third receiving slot and a fifth buffer slot. The fifth buffer slot is formed by the inner wall of the third receiving slot facing the periphery of the lamination body.

[0027] According to one example of this application, the third magnet groove further includes a sixth buffer groove, which is arranged on the side of the third receiving groove facing the first receiving groove and adjacent to the fifth buffer groove.

[0028] According to one example of this application, the sidewall of the first receiving groove facing the third receiving groove is a plane, and the sidewall of the sixth buffer groove facing the first magnet groove is a plane and is substantially parallel to the sidewall of the first receiving groove facing the third receiving groove.

[0029] According to one example of this application, the sixth buffer groove is formed by the inner wall of the third receiving groove facing the first receiving groove, the depth of the sixth buffer groove is 0.8mm-1.5mm, and the length of the first buffer groove is 3mm-6mm in the length direction of the third magnet groove.

[0030] According to one example of this application, the minimum distance (M) between the sixth buffer groove and the first receiving groove is greater than or equal to 3 mm.

[0031] According to an example of this application, the sixth buffer groove is connected to the third receiving groove by an arc surface, and the end face of the fifth buffer groove facing the first receiving groove does not exceed a first straight line, wherein the first straight line is a tangent line that is tangent to the arc surface and passes through the center of the lamination body.

[0032] According to an example of this application, the third magnet groove further includes a seventh buffer groove, which is formed by a recess in the inner wall of the third receiving groove away from the first receiving groove, and the seventh buffer groove is arranged at the end of the third receiving groove away from the sixth buffer groove.

[0033] According to one example of this application, the second magnet slot group further includes a fourth magnet slot, which is arranged between the two third magnet slots and extends circumferentially along the lamination body.

[0034] According to an example of this application, a third rib is formed between the third magnet groove and the fourth magnet groove. In the length direction of the third rib, the maximum distance between the third magnet groove and the fourth magnet groove is the length of the third rib. The ratio of the length to the thickness of the third rib is 5.2-7.4.

[0035] According to an example of this application, the mounting area has a second pressure buffer groove, which is formed by the fourth magnet groove recessed on the inner wall of one side facing the edge of the lamination body. There are two second pressure buffer grooves, which are respectively arranged at both ends of the fourth magnet groove.

[0036] According to an example of this application, the rotor lamination further includes: weight reduction holes, which are arranged on the outer side of the first magnet slot group and symmetrically arranged along a first center line in the radial direction of the lamination body, wherein the first center line is a straight line passing through the center of the lamination body and extending radially along the lamination body.

[0037] The rotor assembly according to the second aspect of this application includes rotor laminations as described in the first aspect of this application and a plurality of magnets, wherein the number of rotor laminations is plurality, the plurality of rotor laminations are stacked and arranged, and the plurality of magnets are fixed in the mounting area.

[0038] According to the rotor assembly of this application, the overall performance of the rotor assembly is improved by setting the rotor laminations of the first aspect described above.

[0039] According to one example of this application, the rotor assembly further includes a protective sleeve disposed radially outside the plurality of rotor laminations.

[0040] The motor according to the third aspect of this application includes the rotor assembly according to the second aspect of this application.

[0041] According to the motor of this application, by setting the rotor assembly of the second aspect described above, the overall performance of the motor is improved.

[0042] The electric assembly according to the fourth aspect of this application includes the motor described according to the third aspect of this application.

[0043] According to the electric powertrain of this application, by providing the motor described in the third aspect above, the overall performance of the electric powertrain is improved.

[0044] The vehicle according to the fifth aspect of this application includes the electric powertrain or motor according to the fourth aspect of this application.

[0045] The vehicle according to this application improves the overall performance of the vehicle by providing the electric assembly or motor described in the fourth aspect above.

[0046] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0047] Figure 1 is a schematic diagram of a rotor assembly according to an embodiment of this application;

[0048] Figure 2 is a partial schematic diagram of a rotor assembly according to an embodiment of this application;

[0049] Figure 3 is a partial schematic diagram of the rotor assembly according to an embodiment of the present application from another angle;

[0050] Figure 4 is a schematic diagram of a rotor assembly according to another embodiment of this application;

[0051] Figure 5 is a partial schematic diagram of Figure 4;

[0052] Figure 6 is a partial schematic diagram of Figure 4 from another angle;

[0053] Figure 7 is a simulation diagram of the stress of the rotor lamination shown in Figure 1 under static state;

[0054] Figure 8 is a simulation diagram of the stress of the rotor lamination shown in Figure 1 under motion.

[0055] Figure 9 shows the variation of the ultimate stress of the rotor lamination shown in Figure 4 with the thickness of the first rib.

[0056] Figure 10 is a graph showing the variation of the leakage magnetic coefficient of the rotor lamination shown in Figure 4 with the thickness of the first rib.

[0057] Figure 11 is a simulation diagram of the stress of the rotor lamination shown in Figure 4 under the condition that L1 / D1 is small at the limiting speed.

[0058] Figure 12 is a simulation diagram of the stress of the rotor lamination shown in Figure 4 under the condition of large L1 / D1 at the limiting speed.

[0059] Figure 13 is a schematic diagram of a vehicle according to an embodiment of this application.

[0060] Reference numerals: Rotor assembly 1000; Rotor lamination 100; Lamination body 10; Mounting area 1; First magnet slot group 11; First magnet slot 111; First receiving slot 1111; First buffer slot 1112; Third buffer slot 1113; First pressure buffer slot 1114; First side wall 1115; Third side wall 1116; Second magnet slot 112; Second receiving slot 1121; Second buffer slot 1122; Second side wall 1123; Fourth side wall 1124; First rib 113; Second rib 114; Second magnet slot group 12; Third magnet slot 121; Third receiving slot 1211; Fifth buffer slot 1212; Sixth buffer slot 1213; Seventh buffer slot 1214; Fourth magnet slot 122; Third rib 123; Second pressure buffer slot 124; Weight reduction hole 13; First center line 14; First straight line 15; Magnet 200; Protective cover 300; Vehicle 2000; Motor 2001; Electric assembly 2002. Detailed Implementation

[0061] The embodiments of this application are described in detail below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain this application, and should not be construed as limiting this application.

[0062] The rotor lamination 100 according to an embodiment of the first aspect of this application is described below with reference to Figures 1-13.

[0063] As shown in Figures 1-3, according to the first aspect embodiment of this application, the rotor lamination 100 includes a lamination body 10. The lamination body 10 is generally circular, with a shaft hole at its center for the shaft to pass through. Multiple lamination bodies 10 can be pressed together to form a component with a certain thickness to facilitate the mating of the rotor core and the shaft.

[0064] The lamination body 10 has multiple mounting areas 1 arranged circumferentially. The number of mounting areas 1 can be two, four, six, eight, etc., and each mounting area 1 corresponds to one magnetic pole. Therefore, this embodiment is not limited by the number of rotor poles and can be applied to rotor structures of four-pole, six-pole, and eight-pole motors 2001. Each mounting area 1 has at least one set of magnet slots, and each set of magnet slots includes at least one magnet slot. The magnet slot penetrates the lamination body 10 in the thickness direction and is used to mount magnets 200.

[0065] The mounting area 1 has a first magnet slot group 11, which includes a first magnet slot 111 and a second magnet slot 112 arranged adjacent to each other and at an angle around the lamination body 10. Specifically, the first magnet slot 111 and the second magnet slot 112 are arranged at a certain angle. There are various arrangements for the first magnet slot 111 and the second magnet slot 112, such as both extending at an angle, or the first magnet slot 111 and the second magnet slot 112 being arranged in a V-shape. The actual arrangement is selected based on the specific circumstances. Furthermore, both the first magnet slot 111 and the second magnet slot 112 are used to mount magnets 200. Therefore, it can be understood that the arrangement of the magnets 200 in this application is not limited; for example, they can be arranged in a V-shaped structure, a U-shaped structure, etc.

[0066] The first magnet groove 111 includes a first receiving groove 1111 and a first buffer groove 1112. The first buffer groove 1112 is connected to one end of the first receiving groove 1111 facing the second magnet groove 112. The first buffer groove 1112 is arranged inside the first receiving groove 1111 in the radial direction of the lamination body 10. The second magnet groove 112 includes a second receiving groove 1121 and a second buffer groove 1122. The second buffer groove 1122 is connected to one end of the second receiving groove 1121 facing the first magnet groove 111. The second buffer groove 1122 is arranged outside the second receiving groove 1121 in the radial direction of the lamination body 10.

[0067] The phrase "the first buffer groove 1112 is arranged inside the first receiving groove 1111 in the radial direction of the lamination body 10" can be understood as meaning that, in the radial direction of the lamination body 10, the first buffer groove 1112 is arranged on the side of the first receiving groove 1111 facing the rotating hole of the lamination body 10. The phrase "the second buffer groove 1122 is arranged outside the second receiving groove 1121 in the radial direction of the lamination body 10" can be understood as meaning that, in the radial direction of the lamination body 10, the second buffer groove 1122 is arranged on the side of the second receiving groove 1121 away from the rotating hole of the lamination body.

[0068] Specifically, a reinforcing rib is formed between the first magnet groove 111 and the second magnet groove 112. The reinforcing rib is mainly used to bear the centrifugal force on the rotor. Thus, in the radial direction of the lamination body 10, the first buffer groove 1112 is arranged on the side of the first receiving groove 1111 facing the shaft hole, and the second buffer groove 1122 is arranged on the side of the second receiving groove 1121 away from the shaft hole. This can extend the stress on the reinforcing rib in two opposite directions, thereby reducing the stress concentration when the reinforcing rib is under force, thus reducing the risk of the reinforcing rib being crushed and improving the reliability of the motor 2001 during operation.

[0069] According to the rotor lamination 100 of this application, by setting a first buffer groove 1112 arranged inside the first receiving groove 1111 in the radial direction of the lamination body 10, and a second buffer groove 1122 arranged outside the second receiving groove 1121 in the radial direction of the lamination body 10, the stress on the reinforcing rib can be extended in two opposite directions, thereby reducing the stress concentration when the reinforcing rib is under force, thus reducing the risk of the rotor lamination 100 being crushed and improving the reliability of the motor 2001 during operation.

[0070] According to an example of this application, as shown in Figures 2-3, the first buffer groove 1112 is formed by a recess in the inner wall of the end adjacent to the first receiving groove 1111 and the second receiving groove 1121. Specifically, referring to Figure 3, the first buffer groove 1112 is formed at the end edge of the inner wall of the side adjacent to the first receiving groove 1111 and the second receiving groove 1121 away from the second receiving groove 1121. At this position, the first receiving groove 1111 is grooved towards the pivot hole of the stamping body 10 to form a first buffer groove that protrudes towards the pivot hole and away from the second receiving groove 1121.

[0071] The second buffer groove 1122 is formed by a recess in the inner wall of the end of the second receiving groove 1121 adjacent to the first receiving groove 1111. Specifically, referring to FIG3, the second buffer groove 1122 is formed at the end edge of the inner wall of the second receiving groove 1121 adjacent to the first receiving groove 1111 away from the first receiving groove 1111. The second receiving groove 1121 is grooved at this position in the direction away from the pivot hole of the stamping body 10, so as to form the second buffer groove 1122 protruding towards the periphery of the stamping body 10 and away from the first receiving groove 1111.

[0072] The recessed forming structure is relatively simple, which reduces the forming difficulty of the entire rotor lamination 100 and thus increases the manufacturing speed of the rotor lamination 100.

[0073] According to an example of this application, as shown in Figures 2-3, in the circumferential direction of the lamination body 10, the first buffer groove 1112 extends obliquely toward the side opposite to the second magnet groove 112, and / or the second buffer groove 1122 extends obliquely toward the side opposite to the first magnet groove 111. It should be noted that a reinforcing rib is formed between the first magnet groove 111 and the second magnet groove 112. The reinforcing rib is mainly used to bear the centrifugal force or pressure on the rotor. Therefore, in the circumferential direction of the lamination body 10, the first buffer groove 1112 and the second buffer groove 1122 extend away from each other, which can extend the stress-bearing area of ​​the reinforcing rib, thereby reducing stress concentration on the reinforcing rib, improving the load-bearing capacity of the reinforcing rib, and reducing the risk of the reinforcing rib being crushed.

[0074] According to an example of this application, as shown in Figures 2-3, the sidewall of the first buffer groove 1112 facing the second receiving groove 1121 is a first sidewall 1115, and the first sidewall 1115 is formed as an arc surface protruding towards the second receiving groove 1121; and / or, the sidewall of the second buffer groove 1122 facing the first receiving groove 1111 is a second sidewall 1123, and the second sidewall 1123 is formed as an arc surface protruding towards the first receiving groove 1111. It is understood that the arc surface structure can further reduce the number of stress points, allowing stress to be dispersed from local stress points to a larger surface area, thereby further reducing local stress concentration under tension.

[0075] According to an example of this application, as shown in Figures 2-3, the sidewall of the first buffer groove 1112 facing the second receiving groove 1121 is the first sidewall 1115, the sidewall of the first receiving groove 1111 facing the second receiving groove 1121 is the third sidewall 1116, the third sidewall 1116 and the first sidewall 1115 together form an arc surface protruding towards the second receiving groove 1121, and / or, the sidewall of the second buffer groove 1122 facing the first receiving groove 1111 is the second sidewall 1123, the sidewall of the second receiving groove 1121 facing the first receiving groove 1111 is the fourth sidewall 1124, the fourth sidewall 1124 and the second sidewall 1123 together form an arc surface protruding towards the first receiving groove 1111. It is understandable that the first receiving groove 1111 and the first buffer groove 1112, as well as the second receiving groove 1121 and the second buffer groove 1122, are all connected by continuous tangent arc surfaces. This can further reduce the stress points on the reinforcing ribs and further improve the stress dispersion effect. As a result, it can further reduce the local stress concentration when under tension.

[0076] According to an example of this application, as shown in Figures 2-3, in the radial direction from the inside to the outside of the lamination body 10, the first receiving groove 1111 extends obliquely toward the side opposite to the second receiving groove 1121, and the second receiving groove 1121 extends circumferentially along the lamination body 10. Specifically, both the first receiving groove 1111 and the second receiving groove 1121 are used to install magnets 200. Thus, it can be understood that the arrangement of magnets 200 in the first receiving groove 1111 and the second receiving groove 1121 is different. The magnets 200 in the first receiving groove 1111 extend obliquely toward the side opposite to the second receiving groove 1121 in the radial direction, which can make the magnetic flux more concentrated and thus reduce magnetic flux leakage. The magnets 200 in the second receiving groove 1121 extend circumferentially along the lamination body 10. Thus, the magnets 200 arranged in the second receiving groove 1121 can provide uniform support on the entire circumference, thereby enhancing the overall rigidity of the rotor and improving the stability of the rotor during high-speed operation.

[0077] According to an example of this application, as shown in Figures 2-3 and 5-6, a first rib 113 is formed between the first magnet slot 111 and the second magnet slot 112. The first rib 113 mainly bears the centrifugal force acting on the rotor lamination 100 at the arrangement position of the first magnet slot group 11 when the rotor is rotating.

[0078] Along the length of the first rib 113, the maximum distance between the first buffer groove 1112 and the second buffer groove 1122 is equal to the length of the first rib 113. The ratio of the length L1 of the first rib 113 to its thickness D1 is 4.8 to 10.2. It should be noted that the thickness of the first rib 113 is the shortest distance between the walls of adjacent ends of the first receiving groove 1111 and the second receiving groove 1121 along the circumferential direction of the lamination body 10. The length of the first rib 113 is the maximum distance between the first buffer groove 1112 and the second buffer groove 1122 along the direction perpendicular to the thickness of the first rib 113.

[0079] Therefore, the ratio of the length L1 of the first rib 113 to the thickness D1 of the first rib 113 is 4.8 to 10.2, which can ensure the structural strength of the first rib 113 while reducing the leakage magnetic coefficient and improving the stress dispersion effect.

[0080] For example, the ratio of the length L1 to the thickness D1 of the second rib 114 can be 4.2, 4.8, 5.4, 6.2, 6.8, 7.4, 9.2, 9.8 or 10.2.

[0081] According to an example of this application, as shown in Figures 2-3 and 5-6, a third buffer groove 1113 is connected to one end of the first receiving groove 1111 away from the first buffer groove 1112. The third buffer groove 1113 is formed by recessing the inner wall of the first receiving groove 1111 on one side facing the periphery of the stamping body 10. Specifically, the first receiving groove 1111 and the edge of the lamination body 10 form a magnetic bridge. It should be noted that, referring to FIG3, one end of the third buffer groove 1113 is arranged on the side of the first receiving groove 1111 facing the periphery of the lamination body 10, and the other end extends circumferentially along the lamination body 10 and is connected to the side wall of the side of the first receiving groove 1111 facing the periphery of the lamination body 10. Thus, the third buffer groove 1113 can extend the length of the magnetic bridge, thereby increasing the force-bearing area of ​​the magnetic bridge and reducing the stress concentration caused by centrifugal force. At the same time, the third buffer groove 1113 is formed by the indentation of the inner wall of the side of the first receiving groove 1111 facing the periphery of the lamination body 10. Thus, the third buffer groove 1113 protrudes on the side facing the periphery of the lamination body 10. The presence of the third buffer groove 1113 shortens the width of the magnetic bridge, thereby reducing the local stiffness of the magnetic bridge and weakening the pressure transmitted to the interior of the lamination body 10, thereby improving the reliability of the rotor lamination 100.

[0082] According to an example of this application, as shown in Figures 2-3 and 5-6, there are two first magnet slots 111, which are respectively disposed on both sides of the first center line 14. The first center line 14 is a straight line passing through the center of the lamination body 10 and extending radially along the lamination body 10. The phrase "two first magnet slots 111 are disposed on both sides of the first center line 14" can be understood to mean that the two first magnet slots 111 can be arranged symmetrically or asymmetrically along the first center line 14.

[0083] Specifically, since the first magnet groove 111 extends inclined towards the side opposite to the second magnet groove 112 in the radial direction from the inside to the outside of the lamination body 10, that is, the two first magnet grooves 111 can be arranged in a V shape, and the opening of the V shape is arranged towards the periphery of the lamination body 10. The V-shaped structure can better guide the magnetic field path, reduce magnetic leakage, and make the magnetic field more concentrated and uniform. Thus, the two first magnet grooves 111 are symmetrically arranged along the first center line 14, which can improve the magnetization effect and thus increase the output torque.

[0084] It should be noted that the first center line 14 can be the d-axis of the magnetic pole, and the two first magnetic slots 111 can be symmetrical along the d-axis of the magnetic pole.

[0085] Optionally, the angle between the first magnet slot 111 and the d-axis is 70°–90°, which is beneficial to improving the rotor's magnetization effect and the utilization rate of the magnet 200.

[0086] According to an example of this application, as shown in Figures 2-3 and 5-6, there are two second magnet slots 112, which are respectively located on both sides of the first center line 14 and arranged between the two first magnet slots 111. The phrase "two second magnet slots 112 are respectively located on both sides of the first center line 14" can be understood as meaning that the two second magnet slots 112 can be symmetrically arranged on both sides of the first center line 14 or asymmetrically arranged. The two second magnet slots 112 are arranged between the two first magnet slots 111 and extend circumferentially along the lamination body 10. Thus, the first magnet slots 111 and the second magnet slots 112 can jointly constrain a U-shaped structure. The U-shaped structure has a simple layout and can optimize the magnetic field distribution. Furthermore, the two second magnet slots 112 can further increase the number of magnets 200 installed, thereby enhancing the magnetic field strength and improving the magnetic field utilization efficiency.

[0087] According to an example of this application, as shown in Figures 2-3 and 5-6, in the radial direction from the inside to the outside of the lamination body 10, the first receiving groove 1111 extends obliquely toward the side opposite to the second receiving groove 1121, and the second receiving groove 1121 extends circumferentially along the lamination body. The length dimension of the first receiving groove 1111 in the extending direction is smaller than the length dimension of the second receiving groove 1121 in the extending direction. This allows for better layout, thereby increasing the amount of magnet 200 used. At the same time, it also optimizes the arrangement of reinforcing ribs, thereby improving the structural strength of the rotor lamination 100.

[0088] According to an example of this application, as shown in Figures 2-3 and 5-6, a second rib 114 is formed between the two second magnet slots 112, wherein the second rib 114 and the first rib 113 jointly bear the centrifugal force acting on the rotor lamination 100 when the rotor is rotating.

[0089] Along the length of the second rib 114, the maximum distance between the two second magnetic grooves 112 is equal to the length of the second rib 114. The ratio of the length L2 of the second rib 114 to its thickness D2 is 4.8-10.2. It should be noted that the length direction of the second rib 114 is the extension direction of the first center line 14. Therefore, the length of the second rib 114 is the maximum distance between the two second magnetic grooves 112 along the extension direction of the first center line 14. The thickness of the second rib is the shortest distance between the two second magnetic grooves 112 along the circumference of the lamination body 10. Thus, the ratio of the length L2 to the thickness D2 of the second rib 114, which is 4.8-10.2, can ensure the structural strength of the second rib 114 while also reducing the magnetic leakage coefficient and improving stress dispersion.

[0090] For example, the ratio of the length L2 to the thickness D2 of the second rib 114 can be 4.2, 4.8, 5.4, 6.2, 6.8, 7.4, 9.2, 9.8 or 10.2.

[0091] According to an example of this application, as shown in Figures 2-3 and 5-6, the first magnet groove 111 has a first pressure buffer groove 1114. The first pressure buffer groove 1114 is connected to the side of the first receiving groove 1111 facing the edge of the lamination body 10, and is arranged at one end of the first receiving groove 1111 near the second receiving groove 1121. It is understood that the first pressure buffer groove 1114 protrudes towards the outer periphery of the lamination body 10. This increases the pressure-bearing area on the side of the first magnet groove 111 facing the edge of the lamination body 10. Therefore, when the rotor is under high-temperature conditions and the protective sleeve 300 exerts pressure on the rotor lamination 100, the first pressure buffer groove 1114 can distribute the stress generated by the pressure more evenly over a larger area, thereby reducing the phenomenon of excessive local stress.

[0092] According to an example of this application, as shown in Figures 2-3 and 5-6, the mounting area 1 has a second magnet slot group 12, which includes at least one third magnet slot 121. The second magnet slot group 12 and the first magnet slot group 11 are arranged radially spaced along the lamination body 10, and in the radial direction of the lamination body 10, the second magnet slot group 12 is arranged outside the first magnet slot group 11. It is understood that each mounting area 1 has at least two layers of magnet slots arranged in the radial direction of the lamination body 10, thereby allowing multiple magnets 200 to be mounted in each mounting area 1. At the same time, since two adjacent magnet slots in each magnet slot group form reinforcing ribs, the overall rigidity of the rotor can be increased.

[0093] For example, as shown in Figure 3, the first magnet slot group 11 includes four magnet slots symmetrically arranged along the d-axis, and the second magnet slot group 12 includes three magnet slots symmetrically arranged along the d-axis. Thus, in the radial direction from the inside to the outside of the lamination body 10, each mounting area 1 includes three and two magnet slots symmetrically arranged along the d-axis, respectively. In other words, multiple reinforcing ribs present a skeleton-like structural layout with progressively decreasing layers along the d-axis. This allows for the accommodation of more magnets 200, while also reducing the radial deformation of the rotor and improving the overall rigidity of the rotor. This prevents the centrifugal force or pressure on the rotor from concentrating on a single reinforcing rib, thereby enabling the rotor to withstand greater centrifugal force or pressure. Furthermore, since the centrifugal force or pressure on the reinforcing ribs is reduced, the thickness of the protective sleeve 300, reinforcing ribs, and magnetic isolation bridge can be reduced, thereby increasing the air gap magnetic flux density and improving the torque and power density of the motor 2001.

[0094] According to an example of this application, as shown in Figures 2-3 and 5-6, there are two third magnet slots 121, which are respectively arranged on both sides of the first center line 14. The first center line 14 is a straight line passing through the center of the lamination body 10 and extending radially along the lamination body 10. In the radial direction of the lamination body 10 from the inside to the outside, the two third magnet slots 121 extend in opposite directions. It can be understood that the two third magnet slots 121 are V-shaped, and the opening of the V-shape is arranged facing the periphery of the lamination body 10. The V-shaped structure can better guide the magnetic field path, suppress magnetic leakage, and make the magnetic field more concentrated and uniform. Therefore, the two first magnet slots 121 are arranged on both sides of the first center line 14, which can improve the magnetization effect and thus increase the output torque. It should be noted that the first center line 14 can be the d-axis of the magnetic pole. Therefore, the two third magnet slots 121 are symmetrical about the d-axis of the magnetic pole.

[0095] Both third magnet slots 121 include a third receiving slot 1211 and a fifth buffer slot 1212. The fifth buffer slot 1212 is formed by the inner wall of the third receiving slot 1211 facing the periphery of the stamping body 10. Specifically, the component between the third receiving groove 1211 and the edge of the lamination body 10 is a magnetic bridge. It should be noted that, referring to Figure 3, one end of the fifth buffer groove 1212 is arranged on the side of the third receiving groove 1211 extending towards the periphery of the lamination body 10, and the other end extends circumferentially along the lamination body 10 and is connected to the side wall opposite to the third receiving groove 1211 and another third magnet groove 121. Thus, the fifth buffer groove 1212 can extend the length of the magnetic bridge, thereby increasing the force-bearing area of ​​the magnetic bridge and reducing stress concentration caused by centrifugal force. At the same time, the fifth buffer groove 1212 protrudes towards the periphery of the lamination body 10, thereby reducing the width of the magnetic bridge and reducing the local stiffness of the magnetic bridge, thereby weakening the pressure transmitted to the interior of the lamination body 10 and improving the reliability of the rotor lamination 100.

[0096] According to an example of this application, as shown in Figures 2-3, the third magnetic groove 121 further includes a sixth buffer groove 1213, which is arranged on the side of the third receiving groove 1211 facing the first receiving groove 1111 and adjacent to the fifth buffer groove 1212. A support arm is defined between the third receiving groove 1211 and the first receiving groove 1111. Therefore, the arrangement of the sixth buffer groove 1213 on the side of the third receiving groove 1211 facing the first receiving groove 1111 can disperse the stress generated by centrifugal force concentrated on the support arm, thereby reducing the risk of the support arm being crushed.

[0097] According to an example of this application, as shown in Figures 2-3, the sidewall of the first receiving groove 1111 facing the third receiving groove 1211 is flat, and the sidewall of the sixth buffer groove 1213 facing the first magnet groove 111 is flat and substantially parallel to the sidewall of the first receiving groove 1111 facing the third receiving groove 1211. This ensures that the centrifugal force of the magnet 200 arranged in the first receiving groove 1111 and the pre-tightening force generated by the protective sleeve 300 can be evenly distributed on the bottom of the sixth buffer groove 1213, thereby reducing stress concentration in the support arm between the first receiving groove 1111 and the third receiving groove 1211.

[0098] According to an example of this application, as shown in Figures 2-3, the sixth buffer groove 1213 is formed by a recess in the inner wall of the third receiving groove 1211 facing the first receiving groove 1111. A support arm is defined between the third receiving groove 1211 and the first receiving groove 1111. The phrase "the sixth buffer groove 1213 is formed by a recess in the inner wall of the third receiving groove 1211 facing the first receiving groove 1111" can be understood as the sixth buffer groove 1213 protruding towards the first receiving groove 1111. Thus, when the rotor is subjected to the compressive force of the protective sleeve 300 under high-temperature conditions, the stress transmission path through the support arm becomes longer. Therefore, by setting the sixth buffer groove 1213, the localized stress caused by the pressure can be concentrated and dispersed over a longer area, thereby reducing the risk of the support arm being crushed, and thus improving the reliability and service life of the rotor lamination 100.

[0099] The depth of the sixth buffer groove 1213 is 0.8mm-1.5mm, and its length is 3mm-6mm along the length of the third magnet groove 121. This design ensures the strength of the support arm and the power output of the motor 2001 while also improving stress dispersion, thereby enhancing the reliability and service life of the rotor lamination 100.

[0100] Understandably, the recess depth of the sixth buffer groove 1213 can be 0.8mm, 1.0mm, 1.2mm, 1.4mm, or 1.5mm. In the extending direction of the third magnet groove 121, the length of the first buffer groove 1112 can be 3mm, 4mm, 5mm, or 6mm.

[0101] According to an example of this application, as shown in Figure 3, the minimum distance M between the sixth buffer groove 1213 and the first receiving groove 1111 is greater than or equal to 3 mm. For example, the minimum distance M between the sixth buffer groove 1213 and the first receiving groove 1111 can be 3 mm, 4 mm or more. The sixth buffer groove 1213 and the first receiving groove 1111 together form a support arm, mainly used to support the magnets 200 fixed in the first receiving groove 1111 and the third receiving groove 1211. Simultaneously, it also increases the rigidity and stability of the structure. Therefore, the distance between the sixth buffer groove 1213 and the first receiving groove 1111 being greater than or equal to 3 mm ensures the structural strength of the support arm, thereby improving the load-bearing capacity of the entire rotor lamination 100.

[0102] According to an example of this application, as shown in Figure 3, the sixth buffer groove 1213 is connected to the third receiving groove 1211 via an arc surface. The end face of the fifth buffer groove 1212 facing the first receiving groove 1111 does not exceed the first straight line 15, wherein the first straight line 15 is a tangent line that is tangent to the arc surface and passes through the center of the lamination body 10. In this way, the strength of the magnetic bridge at this location can be reduced due to the excessive length of the fifth buffer groove 1212, thereby preventing stress distortion when the location is under pressure.

[0103] According to an example of this application, as shown in FIG3, the third magnetic steel groove 121 further includes a seventh buffer groove 1214, which is formed by a recess in the inner wall of the third receiving groove 1211 away from the first receiving groove 1111, and the seventh buffer groove 1214 is arranged at the end of the third receiving groove 1211 away from the sixth buffer groove 1213. It should be noted that, in the radial direction from the inside to the outside of the lamination body 10, the two third magnet grooves 121 extend in opposite directions, that is, the two third magnet grooves 121 form a V shape, and the opening of the V shape faces the edge of the lamination body 10. In other words, the two sides of the third receiving groove 1211 face the edge of the lamination body 10. The seventh buffer groove 1214 is formed by the inner wall of the third receiving groove 1211 facing away from the first receiving groove 1111. It can be understood that the seventh buffer groove 1214 protrudes towards the outer periphery of the lamination body 10. In this way, the pressure-bearing area of ​​the third receiving groove 1211 facing the edge of the lamination body 10 can be increased. Therefore, when the rotor is under high temperature conditions and the protective sleeve 300 exerts a squeezing force on the rotor lamination 100, the seventh buffer groove 1214 can make the stress generated by the pressure more evenly distributed over a larger area, thereby reducing the phenomenon of excessive local stress.

[0104] According to an example of this application, as shown in Figures 2-3, the second magnet slot group 12 further includes a fourth magnet slot 122, which is arranged between the two third magnet slots 121 and extends circumferentially along the lamination body 10. It is understood that the third magnet slots 121 and the fourth magnet slot 122 can together form a U-shaped structure. The U-shaped structure has a simple layout and can optimize the magnetic field distribution. Therefore, providing the fourth magnet slot 122 can further improve the magnetic field utilization efficiency.

[0105] Optionally, the angle between the third magnet groove 121 and the d-axis is 110°–120°, which is beneficial for arranging the fourth magnet groove 122.

[0106] According to an example of this application, as shown in Figures 2-3 and 5-6, a third rib 123 is formed between the third magnet groove 121 and the fourth magnet groove 122, wherein the third rib 123 and the reinforcing rib of the first magnet groove group 11 jointly bear the centrifugal force of the rotor when it rotates.

[0107] Specifically, along the length of the third rib 123, the maximum distance between the third magnet slot 121 and the fourth magnet slot 122 is equal to the length of the third rib 123, and the ratio of the length L3 to the thickness D3 of the third rib 123 is 5.2-7.4. This allows the third rib 123 to effectively share the stress on the reinforcing ribs of the first magnet slot group 11 while also ensuring the structural strength of the third rib 123, guaranteeing high rotor speed, and suppressing rotor magnetic leakage.

[0108] In addition, the ratio of length L3 to thickness D3 is 5.2-7.4, which can prevent the length of the third rib 123 from being too long, thus ensuring the space available for the magnet 200, thereby ensuring the magnetic field strength and improving the rotor space utilization efficiency.

[0109] It should be noted that the thickness of the third rib 123 is the shortest distance between the third magnet groove 121 and the fourth magnet groove 122 in the circumferential direction of the lamination body 10, and the length of the third rib 123 is the maximum distance between the third magnet groove 121 and the fourth magnet groove 122 in the direction perpendicular to the thickness direction of the third rib 123.

[0110] For example, the ratio of the length L3 to the thickness D3 of the third rib 123 can be 5.2, 5.4, 5.6, 5.8, 6.0, 6.2, 6.4, 6.6, 6.8, 7.0, 7.2 or 7.4.

[0111] Optionally, referring to Figure 5, in the radial direction from the inside to the outside of the lamination body 10, the third rib 123 is arranged near the periphery of the lamination body 10, and the first rib 113 and the second rib 114 are arranged on the side of the third rib 123 facing the shaft hole. The second rib 114 and the first rib 113 are arranged at intervals in the circumferential direction of the lamination body, wherein the thickness of the first rib 113, the second rib 114 and the third rib 123 is 3.7mm-4.8mm.

[0112] For example, as shown in Figures 9 and 10, this application analyzed the thickness, leakage magnetic coefficient, and ultimate stress of the first rib 113, the second rib 114, and the third rib 123 in this embodiment. The experiment showed that the ultimate stress decreased linearly within a certain range as the thickness increased, while the leakage magnetic coefficient continued to increase. Under normal circumstances, the thickness of the reinforcing rib is sufficient to meet the maximum power required at the ultimate speed. Therefore, based on the analysis of the thickness, leakage magnetic coefficient, and ultimate stress of the first rib 113, the second rib 114, and the third rib 123, the thickness of the first rib 113, the second rib 114, and the third rib 123 is 3.7 mm to 4.8 mm.

[0113] Meanwhile, at the limiting speed, this application also simulated the stress distribution on the rotor assembly 1000 of this embodiment under the conditions of a small L1 / D1 ratio and a large L1 / D1 ratio. Referring to Figures 11-12, and in conjunction with Figures 9 and 10, it can be clearly seen that when the L1 / D1 ratio is small, the width of the first rib 113 is relatively large. At this time, the leakage magnetic coefficient increases, and the limiting stress decreases accordingly. When the L1 / D1 ratio is large, the length of the first rib 113 is relatively long. At this time, the stress will be distributed between the first magnet slot group 11 and the second magnet slot group 12. The force between the first magnet slot group 11 and the second magnet slot group 12 increases, and the first rib 113 is prone to local stress. Therefore, by setting the thickness of the first rib 113 to 3.7mm-4.8mm and L1 / D1 to 4.8-10.2, the rotor stress concentration at high speed can be suppressed, while also suppressing magnetic leakage and reducing the risk of the first rib 113 being crushed.

[0114] According to an example of this application, as shown in Figures 2-3, the mounting area 1 has a second pressure buffer groove 124. The second pressure buffer groove 124 is formed by a recess in the inner wall of the fourth magnet groove 122 facing the edge of the lamination body 10. There are two second pressure buffer grooves 124, which are respectively arranged at both ends of the fourth magnet groove 122. It can be understood that the second pressure buffer groove 124 protrudes towards the outer periphery of the lamination body 10. In this way, the pressure-bearing area of ​​the fourth magnet groove 122 facing the edge of the lamination body 10 can be increased. Therefore, when the rotor is under high temperature conditions and the protective sleeve 300 exerts a squeezing force on the rotor lamination 100, the second pressure buffer groove 124 can make the stress generated by the pressure more evenly distributed over a larger area, thereby reducing the phenomenon of excessive local stress.

[0115] For example, in Figure 3, the two second pressure buffer grooves 124 are arranged symmetrically along the d-axis of the magnetic pole. One end of the second pressure buffer groove 124 is arranged on the side of the fourth magnetic groove 122 facing the edge of the stamping body 10, and the other end of the second pressure buffer groove 124 is arranged on the side of the fourth magnetic groove 122 facing the third magnetic groove 121.

[0116] According to an example of this application, as shown in Figures 2-3, the rotor lamination 100 further includes weight-reducing holes 13. These holes 13 are arranged on the outer side of the first magnet slot group 11 in the radial direction of the lamination body 10, and are symmetrically arranged along a first center line 14. The first center line 14 is a straight line passing through the center of the lamination body 10 and extending radially along the lamination body 10. The weight-reducing holes 13 are mainly used to reduce the weight of the lamination body 10, thereby reducing the centrifugal force on the lamination body 10 and thus reducing the stress level of the reinforcing ribs and magnetic bridges of the rotor lamination 100 under centrifugal force.

[0117] It should be noted that the first center line 14 is the d-axis of the magnetic pole. Therefore, the phrase "the weight reduction holes 13 are symmetrically arranged along the first center line 14" can be understood as the weight reduction holes 13 being symmetrical along the d-axis of the magnetic pole. This can further improve the uniformity of weight reduction, thereby further improving the uniformity of force distribution in various regions of the rotor lamination 100.

[0118] It should be further noted that the shape of the weight-reducing hole 13 in this application can be various, such as rhombus, circle, trapezoid, etc. The number of weight-reducing holes 13 can be one or more, for example, one, two, three or more.

[0119] Optionally, the weight-reducing hole 13 of this application is bullet-shaped and composed of smooth arcs. The smooth arcs help to reduce stress concentration and make the stress act more evenly on the periphery of the weight-reducing hole 13, thereby improving the overall load-bearing capacity.

[0120] The rotor assembly 1000 according to the second aspect of the present application includes rotor laminations 100 and a plurality of magnets 200 according to the first aspect of the present application. The number of rotor laminations 100 is multiple, and the multiple rotor laminations 100 are stacked and arranged. The multiple magnets 200 are fixed in the mounting area 1.

[0121] Among them, the rotor lamination 100 is an important component of the rotor of the motor 2001. It is usually made of silicon steel sheets or other high magnetic permeability materials. They are formed into specific shapes and structures through stamping processes and stacked together to form a complete rotor.

[0122] The magnet 200 is fixed to the rotor lamination 100 via multiple magnet slots in the mounting area 1. The magnet 200 is mainly used to generate a constant magnetic field to achieve the rotation of the motor 2001. It should be noted that multiple mounting areas 1 are formed on each rotor lamination 100, and at least one set of magnet slots is formed on each mounting area 1. Each set of magnet slots includes at least one magnet slot, which penetrates the lamination body 10 in the thickness direction. The magnet slot is used to mount the magnet 200.

[0123] For example, the number of rotor laminations 100 can be two, three or more.

[0124] The rotor assembly 1000 according to the embodiments of this application improves the overall performance of the rotor assembly 1000 by providing the rotor laminations 100 of the first aspect embodiment described above.

[0125] According to an example of this application, the rotor assembly 1000 further includes a protective sleeve 300, which is fitted radially outward of the plurality of rotor laminations 100. The protective sleeve 300 is generally wrapped around the outer circumferential surface of the rotor laminations 100 under high tension to generate a certain preload on the plurality of rotor laminations, thereby effectively counteracting the centrifugal force on the reinforcing ribs at high speeds, thus breaking through the original speed limit and achieving ultra-high speeds.

[0126] It should be noted that the protective sleeve 300 and the rotor lamination 100 can be assembled using a press-fit or winding process.

[0127] The motor 2001 according to a third aspect embodiment of the present application includes a rotor assembly 1000 according to a second aspect embodiment of the present application.

[0128] According to the embodiments of this application, the overall performance of the motor 2001 is improved by providing the rotor assembly 1000 of the second aspect embodiment described above.

[0129] The electric power assembly 2002 according to the fourth aspect of this application includes the motor 2001 according to the third aspect of this application.

[0130] According to the electric power assembly 2002 of the present application embodiment, by providing the motor 2001 of the third aspect embodiment described above, the overall performance of the electric power assembly 2002 is improved.

[0131] The vehicle 2000 according to the fifth aspect of this application includes an electric powertrain 2002 or a motor 2001 according to the fourth aspect of this application.

[0132] The vehicle 2000 according to the embodiments of this application improves the overall performance of the vehicle 2000 by providing the electric powertrain 2002 or motor 2001 of the third aspect embodiment described above.

[0133] The rotor assembly 1000 according to a second aspect embodiment of the present application is described below with reference to Figures 1-12.

[0134] Referring to Figure 1, the rotor assembly 1000 includes: rotor laminations 100, multiple magnets 200, and a protective sleeve 300. The rotor laminations 100 are multiple and stacked. Each rotor lamination 100 includes a lamination body 10, which has multiple mounting areas 1 arranged circumferentially. Each mounting area 1 corresponds to a magnetic pole, and each mounting area 1 has at least one set of magnet slots. Each set of magnet slots includes at least one magnet slot. The multiple magnets 200 are fixed within the mounting areas 1 via the magnet slots. The protective sleeve 300 is fitted radially outside the multiple rotor laminations 100.

[0135] Specifically, the lamination body 10 is circular, and the lamination body 10 is provided with six mounting areas 1 arranged circumferentially. Each mounting area 1 has two sets of magnet slots, namely a first set of magnet slots 11 and a second set of magnet slots 12. The first set of magnet slots 11 and the second set of magnet slots 12 are arranged radially apart along the lamination body 10, and the second set of magnet slots 12 is arranged radially outside the first set of magnet slots 11.

[0136] The first magnet slot group 11 includes a first magnet slot 111 and a second magnet slot 112. In the radial direction from the inside to the outside of the lamination body 10, the first magnet slot 111 extends obliquely toward the side away from the first magnet slot 111, and the second magnet slot 112 extends circumferentially along the lamination body 10. Furthermore, there are two of each of the first magnet slot 111 and the second magnet slot 112. The two first magnet slots 111 and the two second magnet slots 112 are symmetrically arranged along the d-axis of the magnetic pole, and the two second magnet slots 112 are arranged between the two first magnet slots 111. The two first magnet slots 111 and the two second magnet slot groups 12 are combined to form a U-shaped structure.

[0137] Further, the first magnet groove 111 includes a first receiving groove 1111 and a first buffer groove 1112. The first buffer groove 1112 is connected to one end of the first receiving groove 1111 facing the second magnet groove 112. The second magnet groove 112 includes a second receiving groove 1121 and a second buffer groove 1122. The second buffer groove 1122 is connected to one end of the second receiving groove 1121 facing the first magnet groove 111. In the radial direction of the lamination body 10, the first buffer groove 1112 is arranged radially inside the first receiving groove 1111, and the second buffer groove 1122 is arranged radially outside the second receiving groove 1121.

[0138] The first buffer groove 1112 is formed by a recess in the inner wall of the end adjacent to the first receiving groove 1111 and the second receiving groove 1121. The side wall of the first buffer groove 1112 facing the second receiving groove 1121 is called the first side wall. In the radial direction of the rotor lamination 100, the first side wall is formed as an arc surface convex towards the second receiving groove 1121. The side wall of the first receiving groove 1111 facing the second receiving groove 1121 is called the third side wall. The third side wall and the first side wall together form an arc surface convex towards the second receiving groove 1121.

[0139] The second buffer groove 1122 is formed by the inner wall of the second receiving groove 1121 adjacent to the first receiving groove 1111. The side wall of the second buffer groove 1122 facing the first receiving groove 1111 is the second side wall. In the radial direction of the rotor lamination 100, the second side wall is formed as an arc surface protruding towards the first receiving groove 1111. The side wall of the second receiving groove 1121 facing the first receiving groove 1111 is the fourth side wall. The fourth side wall and the second side wall together form an arc surface protruding towards the first receiving groove 1111.

[0140] The first receiving groove 1111 is connected to a third buffer groove 1113 at one end away from the first buffer groove 1112. The third buffer groove 1113 is formed by the recess of the inner wall of the first receiving groove 1111 on one side facing the periphery of the stamping body 10.

[0141] The first magnet groove 111 has a first pressure buffer groove 1114, which is formed by the inner wall of the first receiving groove 1111 facing the edge of the stamping body 10. The first pressure buffer groove 1114 is arranged at one end of the first receiving groove 1111 near the second receiving groove 1121.

[0142] The second magnet slot group 12 includes a third magnet slot 121 and a fourth magnet slot 122. In the radial direction from the inside to the outside of the lamination body 10, the third receiving slot 1211 extends obliquely toward the side opposite to the fourth receiving slot, and the fourth receiving slot extends circumferentially along the lamination body 10. Further, there are two third magnet slots 121. The two third magnet slots 121 and one fourth magnet slot 122 are symmetrically arranged along the d-axis of the magnetic pole, and the fourth magnet slot 122 is arranged between the two third magnet slots 121. The two third magnet slots 121 and the fourth magnet slot 122 are combined to form a U-shaped structure.

[0143] Both third magnet slots 121 include: a third receiving slot 1211, a fifth buffer slot 1212, a sixth buffer slot 1213, and a seventh buffer slot 1214. The fifth buffer slot 1212 is formed by a recess in the inner wall of the third receiving slot 1211 at one end facing the periphery of the stamping body 10. The sixth buffer slot 1213 is arranged on the side of the third receiving slot 1211 facing the first receiving slot 1111 and is formed by a recess in the inner wall of the third receiving slot 1211 on the side facing the first receiving slot 1111, and is adjacent to the fifth buffer slot 1212. The seventh buffer slot 1214 is formed by a recess in the inner wall of the third receiving slot 1211 on the side away from the first receiving slot 1111, and is arranged at the end of the third receiving slot 1211 away from the sixth buffer slot 1213.

[0144] Furthermore, the side wall of the first receiving groove 1111 facing the third receiving groove 1211 is a plane, the side wall of the sixth buffer groove 1213 facing the first magnet groove 111 is a plane and is parallel to the side wall of the first receiving groove 1111 facing the third receiving groove 1211, the sixth buffer groove 1213 and the third receiving groove 1211 are connected by an arc surface, and the end face of the fifth buffer groove 1212 facing the first receiving groove does not exceed the first straight line 15, wherein the first straight line 15 is a tangent line that is tangent to the arc surface and passes through the center of the stamping body 10.

[0145] The sixth buffer groove 1213 has a recess depth of 0.8mm-1.5mm. In the extension direction of the third magnet groove 121, the length of the sixth buffer groove 1213 is 3mm-6mm. The distance between the sixth buffer groove 1213 and the first receiving groove 1111 is greater than or equal to 3mm.

[0146] The mounting area 1 also has a second pressure buffer groove 124, which is formed by the recess of the inner wall of the fourth magnet groove 122 toward the edge of the stamping body 10. There are two second pressure buffer grooves 124, which are respectively arranged at both ends of the fourth magnet groove 122.

[0147] A first rib 113 is formed between the first magnet groove 111 and the second magnet groove 112. In the extension direction of the first rib 113, the maximum distance between the first buffer groove 1112 and the second buffer groove 1122 is the length of the first rib 113. The ratio of the length L1 of the first rib 113 to the thickness D1 of the first rib 113 is 4.8 to 10.2.

[0148] A second rib 114 is formed between the two second magnet grooves 112. In the extension direction of the second rib 114, the maximum distance between the two second magnet grooves 112 is the length of the second rib 114. The ratio of the length L2 of the second rib 114 to the thickness D2 of the second rib 114 is 4.8-10.2.

[0149] A third rib 123 is formed between the third magnet groove 121 and the fourth magnet groove 122. In the extension direction of the third rib 123, the maximum distance between the third magnet groove 121 and the fourth magnet groove 122 is the length of the third rib 123. The ratio of the length L3 of the third rib 123 to the thickness D3 is 5.2-7.4.

[0150] For example, as shown in Figures 7 and 8, this application simulated the stress distribution of the rotor lamination 100 containing the above-mentioned multiple buffer grooves in the static and dynamic states. The experiment showed that the stress in both the static and dynamic states was mainly distributed on the first rib 113, the second rib 114, the third rib 123, and the magnetic isolation bridge. In the dynamic state, it can be clearly seen that the stress on the first rib 113, the second rib 114, the third rib 123, and the magnetic isolation bridge was dispersed.

[0151] According to the rotor lamination 100 of this application, by setting a first buffer groove 1112 arranged inside the first receiving groove 1111 in the radial direction of the lamination body 10, and a second buffer groove 1122 arranged outside the second receiving groove 1121 in the radial direction of the lamination body 10, the stress on the reinforcing rib can be extended in opposite directions, thereby reducing the stress concentration of the reinforcing rib when it is under tension and compression, thus reducing the risk of the rotor lamination 100 being crushed and improving the reliability of the motor 2001 during operation.

[0152] In the description of this application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicating the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application.

[0153] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means two or more, unless otherwise explicitly specified.

[0154] In this application, unless otherwise expressly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this application according to the specific circumstances.

[0155] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0156] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A rotor lamination (100), wherein, include: A lamination body (10) is provided with a plurality of mounting areas (1) arranged at intervals along the circumference. Each mounting area (1) forms a first magnet groove group (11). The first magnet groove group (11) includes a first magnet groove (111) and a second magnet groove (112) arranged adjacent to each other and at an included angle on the circumference of the lamination body (10). The first magnet groove (111) includes a first receiving groove (1111) and a first buffer groove (1112). The first buffer groove (1112) is connected to one end of the first receiving groove (1111) facing the second magnet groove (112). The first buffer groove (1112) is arranged inside the first receiving groove (1111) in the radial direction of the lamination body (10). The second magnet groove (112) includes a second receiving groove (1121) and a second buffer groove (1122). The second buffer groove (1122) is connected to one end of the second receiving groove (1121) facing the first magnet groove (111). The second buffer groove (1122) is arranged on the outer side of the second receiving groove (1121) in the radial direction of the lamination body (10).

2. The rotor lamination (100) according to claim 1, wherein, The first buffer groove (1112) is formed by a recess in the inner wall of the first receiving groove (1111) and the second receiving groove (1121) adjacent to each other, and / or the second buffer groove (1122) is formed by a recess in the inner wall of the second receiving groove (1121) and the first receiving groove (1111).

3. The rotor lamination (100) according to any one of claims 1-2, wherein, In the circumferential direction of the lamination body (10), the first buffer groove (1112) extends obliquely toward the side opposite to the second magnet groove (112), and / or the second buffer groove (1122) extends obliquely toward the side opposite to the first magnet groove (111).

4. The rotor lamination (100) according to any one of claims 1-3, wherein, The sidewall of the first buffer groove (1112) facing the second receiving groove (1121) is a first sidewall (1115), and the first sidewall (1115) is formed as an arc surface protruding towards the second receiving groove (1121), and / or, The sidewall of the second buffer groove (1122) facing the first receiving groove (1111) is a second sidewall (1123), and the second sidewall (1123) is formed as an arc surface protruding towards the first receiving groove (1111).

5. The rotor lamination (100) according to any one of claims 1-4, wherein, The sidewall of the first buffer groove (1112) facing the second receiving groove (1121) is a first sidewall (1115), and the sidewall of the first receiving groove (1111) facing the second receiving groove (1121) is a third sidewall (1116). The third sidewall (1116) and the first sidewall (1115) together form an arc surface that protrudes towards the second receiving groove (1121), and / or, The sidewall of the second buffer groove (1122) facing the first receiving groove (1111) is the second sidewall (1123), and the sidewall of the second receiving groove (1121) facing the first receiving groove (1111) is the fourth sidewall (1124). The fourth sidewall (1124) and the second sidewall (1123) together form an arc surface that protrudes towards the first receiving groove (1111).

6. The rotor lamination (100) according to any one of claims 1-5, wherein, In the radial direction from the inside to the outside of the lamination body (10), the first receiving groove (1111) extends obliquely toward the side opposite to the second receiving groove (1121), and the second receiving groove (1121) extends circumferentially along the lamination body (10).

7. The rotor lamination (100) according to claim 6, wherein, A first rib (113) is formed between the first magnetic groove (111) and the second magnetic groove (112). In the length direction of the first rib (113), the maximum distance between the first buffer groove (1112) and the second buffer groove (1122) is the length of the first rib (113). The ratio of the length of the first rib (113) to the thickness of the first rib (113) is 4.8 to 10.

2.

8. The rotor lamination (100) according to any one of claims 6-7, wherein, The first receiving groove (1111) is connected to a third buffer groove (1113) at one end away from the first buffer groove (1112). The third buffer groove (1113) is formed by the recess of the inner wall of the first receiving groove (1111) facing the periphery of the stamping body (10).

9. The rotor lamination (100) according to any one of claims 6-8, wherein, There are two first magnet slots (111), which are respectively located on both sides of the first center line (14). The first center line (14) is a straight line that passes through the center of the lamination body (10) and extends radially along the lamination body (10).

10. The rotor lamination (100) according to claim 9, wherein, There are two second magnetic steel grooves (112), which are respectively located on both sides of the first center line (14) and arranged between the two first magnetic steel grooves (111).

11. The rotor lamination (100) according to claim 10, wherein, In the radial direction from the inside to the outside of the lamination body (10), the first receiving groove (1111) extends obliquely toward the side opposite to the second receiving groove (1121), the second receiving groove (1121) extends circumferentially along the lamination body (10), and the length dimension of the first receiving groove (1111) in the extending direction is smaller than the length dimension of the second receiving groove (1121) in the extending direction.

12. The rotor lamination (100) according to any one of claims 10-11, wherein, A second rib (114) is formed between the two second magnetic grooves (112). The maximum distance between the two second magnetic grooves (112) in the length direction of the second rib (114) is the length of the second rib (114). The ratio of the length of the second rib (114) to the thickness of the second rib (114) is 4.8-10.

2.

13. The rotor lamination (100) according to any one of claims 1-12, wherein, The first magnet groove (111) has a first pressure buffer groove (1114), which is connected to the side of the first receiving groove (1111) facing the edge of the punch body (10). The first pressure buffer groove (1114) is arranged at one end of the first receiving groove (1111) near the second receiving groove (1121).

14. The rotor lamination (100) according to any one of claims 1-13, wherein, The mounting area (1) is formed with a second set of magnet grooves (112), the second set of magnet grooves (112) includes at least one third magnet groove (121), the second set of magnet grooves (112) and the first set of magnet grooves (11) are arranged at a radial interval along the lamination body (10), and in the radial direction of the lamination body (10), the second set of magnet grooves (112) is arranged outside the first set of magnet grooves (11).

15. The rotor lamination (100) according to claim 14, wherein, There are two third magnet slots (121), which are respectively located on both sides of the first center line (14). The first center line (14) is a straight line passing through the center of the lamination body (10) and extending radially along the lamination body (10). In the radial direction of the lamination body (10) from the inside to the outside, the two third magnet slots (121) extend in opposite directions. Both of the third magnet slots (121) include a third receiving slot (1211) and a fifth buffer slot (1212), wherein the fifth buffer slot (1212) is formed by the inner wall of the third receiving slot (1211) facing the periphery of the stamping body (10).

16. The rotor lamination (100) according to claim 15, wherein, The third magnetic steel groove (121) further includes a sixth buffer groove (1213), which is arranged on the side of the third receiving groove (1211) facing the first receiving groove (1111) and adjacent to the fifth buffer groove (1212).

17. The rotor lamination (100) according to claim 16, wherein, The sidewall of the first receiving groove (1111) facing the third receiving groove (1211) is a plane, and the sidewall of the sixth buffer groove (1213) facing the first magnet groove (111) is a plane and is basically parallel to the sidewall of the first receiving groove (1111) facing the third receiving groove (1211).

18. The rotor lamination (100) according to claim 17, wherein, The sixth buffer groove (1213) is formed by the inner wall of the third receiving groove (1211) facing the first receiving groove (1111). The depth of the sixth buffer groove (1213) is 0.8mm-1.5mm. In the length direction of the third magnetic groove (121), the length of the first buffer groove (1112) is 3mm-6mm.

19. The rotor lamination (100) according to any one of claims 17-18, wherein, The minimum distance (M) between the sixth buffer groove (1213) and the first receiving groove (1111) is greater than or equal to 3 mm.

20. The rotor lamination (100) according to any one of claims 16-19, wherein, The sixth buffer groove (1213) is connected to the third receiving groove (1211) by an arc surface. The end face of the fifth buffer groove (1212) facing the first receiving groove (1111) does not exceed the first straight line (15), wherein the first straight line (15) is a tangent line that is tangent to the arc surface and passes through the center of the stamping body (10).

21. The rotor lamination (100) according to any one of claims 16-20, wherein, The third magnetic steel groove (121) further includes a seventh buffer groove (1214), which is formed by the inner wall of the third receiving groove (1211) facing away from the first receiving groove (1111). The seventh buffer groove (1214) is arranged at the corner of the third receiving groove (1211) facing away from the sixth buffer groove (1213).

22. The rotor lamination (100) according to any one of claims 15-21, wherein, The second magnetic groove (112) group further includes a fourth magnetic groove (122), which is arranged between the two third magnetic grooves (121) and extends circumferentially along the lamination body (10).

23. The rotor lamination (100) according to claim 22, wherein, A third rib (123) is formed between the third magnet groove (121) and the fourth magnet groove (122). The maximum distance between the third magnet groove (121) and the fourth magnet groove (122) along the length direction of the third rib (123) is the length of the third rib (123). The ratio of the length to the thickness of the third rib (123) is 5.2-7.

4.

24. The rotor lamination (100) according to any one of claims 22-23, wherein, The installation area (1) has a second pressure buffer groove (124), which is formed by the recess of the inner wall of the fourth magnet groove (122) facing the edge of the punch body (10). There are two second pressure buffer grooves (124), which are respectively arranged at both ends of the fourth magnet groove (122).

25. The rotor lamination (100) according to any one of claims 1-24, wherein, It also includes: a weight reduction hole (13), which is arranged on the outer side of the first magnet slot group (11) in the radial direction of the lamination body (10) and symmetrically arranged along the first center line (14), wherein the first center line (14) is a straight line passing through the center of the lamination body (10) and extending radially along the lamination body (10).

26. A rotor assembly (1000), wherein, Includes a rotor lamination (100) according to any one of claims 1-25 and a plurality of magnets (200), wherein the number of rotor laminations (100) is plurality, the plurality of rotor laminations (100) are stacked and arranged, and the plurality of magnets (200) are fixed in the mounting area (1).

27. The rotor assembly (1000) according to claim 26, wherein, It also includes a protective sleeve (300) which is fitted on the radial outer side of the plurality of rotor laminations (100).

28. An electric motor, wherein, Includes the rotor assembly (1000) according to any one of claims 26-27.

29. An electric powertrain, wherein, Includes the motor according to claim 28.

30. A vehicle, wherein, Includes the electric assembly or motor as described in claim 29.