Rotor structure and electric motor

Abstract

Provided in the present application are a rotor structure and an electric motor. The rotor structure comprises: two first rotor assemblies, each of which comprises a first rotor core and a first permanent magnet, wherein the first rotor core and the first permanent magnet are arranged adjacent to each other, the radial outer side of the first rotor core is provided with a projection extending in the radial direction of the first rotor core, and the first rotor core is provided with a first shaft hole through which a rotating shaft passes; and a second rotor assembly, which comprises a second rotor core and second permanent magnets, wherein the second rotor core is provided with a second shaft hole, and the second rotor core is provided with a plurality of steel magnet slots in a circumferential direction, each steel magnet slot being provided with one second permanent magnet therein. The two first rotor assemblies respectively being disposed at both ends of the second rotor assembly, with the second rotor core being disposed between the first permanent magnets of the two first rotor assemblies, solves the problems in the prior art of high assembly difficulty and low electric motor reliability due to a strong repulsive force between a plurality of rotor assemblies.

Description

Rotor structure and motor Technical Field

[0001] This application relates to the field of permanent magnet motor technology, and more specifically, to a rotor structure and motor. This application claims priority to a patent application filed with the State Intellectual Property Office of China on December 4, 2023, with application number 2023116434902 and titled “Rotor Structure and Motor.” Background Art

[0002] Permanent magnet motors (PMMs), with their advantages of compact size and high efficiency, are widely used in air conditioners, industrial equipment, new energy vehicles, and other fields. With the improvement of motor energy efficiency standards, higher efficiency levels are being placed on motors. For PMMs, further improvements in efficiency and torque density are needed. One of the main technical approaches to improving motor efficiency and torque density is to integrate permanent magnets to achieve greater air gap flux density and greater magnetic flux. However, due to the fixed rotor magnetic circuit structure, efficiency gains are limited. Another approach is to utilize the rotor structure to increase the motor's saliency ratio and reluctance torque to compensate for the lack of permanent magnet torque. This approach can achieve efficiency comparable to that of PMMs, but generally requires a larger rotor volume, resulting in a lower torque density. For current PMMs, improving the rotor's magnetic field concentration is an effective way to further achieve higher efficiency and higher torque density.

[0003] A new type of permanent magnet motor has emerged in the prior art, which improves the energy efficiency of permanent magnet motors by combining multiple rotor assemblies. However, its complex structure and the repulsive forces generated during assembly of the multiple rotor assemblies make assembly difficult and the motor reliability low.

[0004] The above problems have not yet been effectively solved.

[0005] Summary of the Invention

[0006] The main purpose of the present application is to provide a rotor structure and a motor to solve the problems of the existing multi-rotor assembly having great difficulty in assembly and low motor reliability due to the large repulsive force.

[0007] To achieve the above objectives, according to one aspect of the present application, a rotor structure is provided, comprising: a first rotor assembly, the first rotor assembly being arranged in two groups, each group of the first rotor assemblies comprising a first rotor core and a first permanent magnet, the first rotor core and the first permanent magnet being arranged adjacent to each other, a radially outer portion of the first rotor core being provided with a protrusion extending radially along the first rotor core, the first rotor core being provided with a first axial hole for a rotating shaft to pass through; and a second rotor assembly, the second rotor assembly comprising a second rotor core and a second permanent magnet, the second rotor core being provided with a second axial hole, a plurality of magnetic steel slots being provided circumferentially along the second rotor core, each magnetic steel slot being provided with a second permanent magnet. The two groups of the first rotor assemblies are respectively arranged at both ends of the second rotor assembly, the second rotor core being arranged between the first permanent magnets of the two groups of the first rotor assemblies, and the first permanent magnet being arranged between an end of the second rotor assembly and the first rotor core.

[0008] Furthermore, there are one or more protrusions extending outward in the radial direction of the first rotor core.

[0009] Furthermore, the number of the protrusions 23 is a, and a / 4 is an integer.

[0010] Furthermore, there are multiple protrusions, which are projected onto an axial end face of the rotor structure along the axial direction of the rotor structure. The geometric center of the protrusion or the geometric center of adjacent protrusions is connected with the central axis of the first rotor core. The central angle formed between adjacent connecting lines is b, and the number of pole pairs of the rotor structure is p, where b / 360 / 2p=b0, and b0 is an integer.

[0011] Furthermore, b / (360 / 2p)=b0, where b0 is an odd number.

[0012] Furthermore, projecting onto an axial end face of the rotor structure along the axial direction of the rotor structure, the length of a line connecting the central axis of the first rotor core and any point on the outer circle of the first rotor core is c, and the length of a line connecting the central axis of the second rotor core and any point on the outer circle of the second rotor core is d, where max(c)=max(d).

[0013] Furthermore, projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, the length of a line connecting the central axis of the first rotor core and any point on the outer circumference of the first permanent magnet is e, the maximum length between the central axis of the second rotor core and the end of the second permanent magnet away from the second axial hole is f, and the length of a line connecting the central axis of the second rotor core and any point on the outer circumference of the second rotor core is d, where min(e)=f, or max(e)≤max(d).

[0014] Furthermore, there are multiple protrusions, and the multiple protrusions are arranged in pairs along the circumferential direction of the first rotor core.

[0015] Furthermore, the first permanent magnet is an integral disc structure, which is divided into a plurality of regions with different polarities according to the magnetization direction.

[0016] Furthermore, projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, positions of at least one pair of protrusions correspond to positions of magnetic pole dividing lines of adjacent polarity regions of the first permanent magnet.

[0017] Furthermore, two adjacent pairs of protrusions are symmetrically arranged about a center line of one polarity region of the first permanent magnet.

[0018] Furthermore, the length of the protrusion extending in the radial direction of the first rotor core is g, and the minimum thickness of the first rotor core in the axial direction is h, wherein g≥0.3*h.

[0019] Furthermore, projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, the thickness of the second permanent magnet along its magnetization direction is i, and the spacing width between adjacent protrusions along the tangential direction of the first rotor core is j, where j≥0.25*i.

[0020] Furthermore, the first rotor core is provided with a limiting member, the first permanent magnet is provided with a limiting structure, and the limiting member and the limiting structure are provided correspondingly.

[0021] Furthermore, there are multiple limiting members and multiple limiting structures, and the multiple limiting members and the multiple limiting structures are arranged in a one-to-one correspondence.

[0022] Furthermore, a boss is provided on the side of the first rotor core facing the first permanent magnet, the boss is provided with a first shaft hole for the rotating shaft to pass through, and an avoidance channel is provided on the first permanent magnet, and part of the boss is passed through the avoidance channel.

[0023] Furthermore, a rotor assembly dynamic balance adjustment structure is provided on the first rotor core.

[0024] Furthermore, the first rotor core and the second rotor core are both made of magnetic conductive material.

[0025] Furthermore, the first rotor core is formed by stamping magnetic steel plates, and the second rotor core is formed by laminating silicon steel sheets.

[0026] Furthermore, a second rotor core lobe is formed between two adjacent magnetic steel slots on the second rotor core. When the polarity region of the first permanent magnet adjacent to the second rotor core lobe in the axial direction is the first polarity, the polarity regions of the two second permanent magnets adjacent to the second rotor core lobe in the circumferential direction are also the first polarity.

[0027] According to another aspect of the present application, a motor is provided, including a rotor structure and a stator structure, wherein the rotor structure is the above-mentioned rotor structure.

[0028] By applying the technical solution of the present application, the rotor structure includes a first rotor assembly and a second rotor assembly. The magnetic lines of force emitted from the axial direction of the first rotor assembly and the magnetic lines of force emitted from the radial direction of the second rotor assembly are concentrated on the iron core of the rotor structure and then enter the air gap, which can greatly improve the magnetic concentration effect of the rotor structure. The first rotor assembly is set into two groups, and each group of the first rotor assembly includes a first rotor core and a first permanent magnet. The first rotor core and the first permanent magnet are arranged adjacent to each other. The circumference of the first rotor core is provided with a protrusion extending along the circumference of the first rotor core, which is used to guide away part of the magnetic lines of force of the first permanent magnet so that the magnetic lines of force directly pass through the air gap and enter the stator. This can reduce the repulsive force between the first rotor assembly and the second rotor assembly, reduce the difficulty of assembly, and solve the problem of high assembly difficulty and low motor reliability caused by large repulsive force in the prior art multi-rotor assembly. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] The drawings that constitute part of this application are used to provide a further understanding of this application. The illustrative embodiments of this application and their descriptions are used to explain this application and do not constitute an improper limitation on this application. In the drawings:

[0030] FIG1 shows a schematic structural diagram of a rotor assembly according to a first embodiment of the present application;

[0031] FIG2 shows a schematic structural diagram of a second embodiment of a rotor assembly according to the present application;

[0032] FIG3 shows a schematic structural diagram of a third embodiment of a rotor assembly according to the present application;

[0033] FIG4 shows a schematic structural diagram of a fourth embodiment of a rotor assembly according to the present application;

[0034] FIG5 shows a schematic structural diagram of a fifth embodiment of a rotor assembly according to the present application;

[0035] FIG6 shows a schematic structural diagram of a sixth embodiment of a rotor assembly according to the present application;

[0036] FIG7 shows a schematic structural diagram of a seventh embodiment of a rotor assembly according to the present application;

[0037] FIG8 shows a schematic structural diagram of an eighth embodiment of a rotor assembly according to the present application;

[0038] FIG9 shows a schematic structural diagram of a ninth embodiment of a rotor assembly according to the present application;

[0039] FIG10 shows a schematic structural diagram of a tenth embodiment of a rotor assembly according to the present application;

[0040] FIG11 shows a schematic structural diagram of an eleventh embodiment of a rotor assembly according to the present application;

[0041] FIG12 shows a schematic structural diagram of a twelfth embodiment of a rotor assembly according to the present application;

[0042] FIG13 shows a schematic structural diagram of a rotor assembly according to a thirteenth embodiment of the present application;

[0043] FIG14 is a schematic diagram showing a comparison between the rotor assembly according to the present application and the magnetic field focusing technology of the prior art;

[0044] FIG15 is a schematic diagram showing a comparison of no-load flux linkage of a rotor assembly according to the present application and that of the prior art;

[0045] FIG16 is a schematic diagram showing a comparison of the air gap flux density between the rotor assembly according to the present application and the prior art.

[0046] The above drawings include the following reference numerals:

[0047] 10. Second rotor assembly;

[0048] 11. Second rotor core; 111. Second rotor core petal;

[0049] 12. a second permanent magnet;

[0050] 13. Second shaft hole;

[0051] 20. First rotor assembly;

[0052] 21. First rotor core;

[0053] 22. First shaft hole; 211. Limiting member;

[0054] 23. bulge;

[0055] 24. First permanent magnet; 241. Limiting structure; 242. Avoidance channel;

[0056] 25. Boss;

[0057] L. Central axis. DETAILED DESCRIPTION

[0058] It should be noted that, in the absence of conflict, the embodiments and features of the embodiments in this application can be combined with each other. The present application will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0059] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0060] It should be noted that the terms "first", "second", etc. in the specification and claims of the present application and the above-mentioned drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present application described herein can, for example, be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0061] Now, exemplary embodiments according to the present application will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be interpreted as being limited to the embodiments described herein. It should be understood that these embodiments are provided to make the disclosure of this application thorough and complete, and to fully convey the concepts of these exemplary embodiments to those of ordinary skill in the art. In the accompanying drawings, for the sake of clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to represent the same devices, and thus their descriptions will be omitted.

[0062] 1 to 13 , in a specific embodiment of the present application, a rotor structure is provided.

[0063] Specifically, the rotor structure includes a first rotor assembly 20, which is arranged in two groups. Each group of first rotor assemblies 20 includes a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. A protrusion 23 extending radially along the first rotor core 21 is provided on the radially outer side of the first rotor core 21. The first rotor core 21 defines a first axial hole 22 for the shaft to pass through. A second rotor assembly 10 includes a second rotor core 11 and a second permanent magnet 12. The second rotor core 11 defines a second axial hole 13. Multiple magnetic steel slots are circumferentially arranged in the second rotor core 11, each of which contains a second permanent magnet 12. The two groups of first rotor assemblies 20 are respectively arranged at both ends of the second rotor assembly 10. The second rotor core 11 is disposed between the first permanent magnets 24 of the two groups of first rotor assemblies 20. The first permanent magnets 24 are disposed between the ends of the second rotor assembly 10 and the first rotor core 21.

[0064] The magnetic lines of force emitted from the axial direction of the first rotor assembly 20 and the magnetic lines of force emitted from the radial direction of the second rotor assembly 10 enter the air gap after being magnetized on the iron core of the rotor structure, which can greatly improve the magnetization effect of the rotor structure. The first rotor assembly 20 is set into two groups, and each group of the first rotor assembly 20 includes a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. The circumference of the first rotor core 21 is provided with a protrusion 23 extending along the circumference of the first rotor core 21, which is used to guide away part of the magnetic lines of force of the first permanent magnet 24, so that the magnetic lines of force directly pass through the air gap into the stator, which can reduce the repulsive force between the first rotor assembly 20 and the second rotor assembly 10 and reduce the difficulty of assembly.

[0065] As shown in Figure 1, in this embodiment, the rotor structure includes a first rotor assembly 20 and a second rotor assembly 10, which can greatly improve the magnetic concentration effect of the rotor structure. The first rotor assembly 20 is set into two groups, and each group of first rotor assemblies 20 includes a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. The radial outer side of the first rotor core 21 is provided with a protrusion 23 extending radially along the first rotor core 21, which reduces the repulsive force between the rotor assemblies and reduces the difficulty of assembly. The magnetic lines of force emitted from the axial direction of the first rotor assembly 20 and the magnetic lines of force emitted from the radial direction of the second rotor assembly 10 enter the air gap after being concentrated on the first rotor core 21 and the second rotor core 11, which can greatly improve the magnetic concentration effect of the rotor structure.

[0066] Furthermore, as shown in FIG. 2 and FIG. 7 , there are one or more protrusions 23 extending outwardly in the radial direction of the first rotor core 21 .

[0067] In one embodiment of the present application, the number of protrusions 23 provided on the first rotor core 21 is one, and the protrusion 23 guides away part of the magnetic lines of force of the first permanent magnet 24 so that it directly passes through the air gap into the stator, which can reduce the repulsive force between the first rotor assembly 20 and the second rotor assembly 10 and reduce the difficulty of assembly.

[0068] Furthermore, the number of the protrusions 23 is a, and a / 4 is an integer.

[0069] In another embodiment of the present application, the number of protrusions 23 provided on the first rotor core 21 is a multiple of 4, such as 4, 8, 12, or 16. Optimally, the number of protrusions 23 provided on the first rotor core 21 is four. An even number of protrusions 23 can symmetrically distribute the interaction force between the first rotor assembly 20 and the second rotor assembly 10. However, an excessive number of protrusions 23 can reduce the number of magnetic lines of force from the first rotor assembly 20 entering the second rotor core 11, thereby reducing the magnetic field concentration effect of the rotor assembly.

[0070] Furthermore, there are multiple protrusions 23, which are projected onto an axial end face of the rotor structure along the axial direction of the rotor structure. The geometric center of the protrusion 23 or the geometric center of adjacent protrusions 23 is connected with the central axis of the first rotor core 21. The central angle formed between adjacent connecting lines is b, and the number of pole pairs of the rotor structure is p, where b / 360 / 2p=b0, and b0 is an integer.

[0071] As shown in Figures 5 and 9, the central angle between two adjacent protrusions 23 is b, and the pole pair number of the rotor structure is p, where b / 360 / 2p=b0, b0 is an integer. This setting can ensure the relative position of the protrusion 23 and the polar region of the first rotor assembly 20, ensuring that the protrusion 23 plays the most suitable role in reducing the repulsive force between the rotor assemblies.

[0072] Furthermore, b / (360 / 2p)=b0, where b0 is an odd number.

[0073] In another embodiment of the present application, preferably, b / 360 / 2p=b0, where b0 is an odd number. This configuration is advantageous in that b / (360 / 2p) is an odd number, which ensures that the polarity regions of the corresponding positions of each pair of protrusions are the same, thereby improving the uniformity of the magnetic distribution.

[0074] Furthermore, projecting onto an axial end face of the rotor structure along the axial direction of the rotor structure, the length of a line connecting the central axis of the first rotor core and any point on the outer circle of the first rotor core is c, and the length of a line connecting the central axis of the second rotor core and any point on the outer circle of the second rotor core is d, where max(c)=max(d).

[0075] As shown in conjunction with Figures 3 and 4 , in another embodiment of the present application, the length between the central axis of the first rotor core 21 and the outer circumference of the first rotor core 21 is c, and the length between the central axis of the second rotor core 11 and the outer circumference of the second rotor core 11 is d, where max(c) = max(d). In this embodiment, the setting of max(c) = max(d) ensures a certain air gap width between the rotor assembly and the stator assembly, increasing the operational reliability of the motor and making the rotor structure more practical.

[0076] Furthermore, projecting onto an axial end face of the rotor structure along the axial direction of the rotor structure, the length of the line between the central axis of the first rotor core 21 and any point on the outer circle of the first permanent magnet 24 is e, the length between the central axis of the second rotor core 11 and the end of the second permanent magnet 12 away from the second axial hole 13 is f, and the length of the line between the central axis of the second rotor core 11 and any point on the outer circle of the second rotor core 11 is d, wherein min(e)=f, or max(e)≤max(d). This setting can limit the distance between the first permanent magnet 24 and the second permanent magnet 12 and the central axis of the rotor, so as to achieve the mutual superposition of the magnetic lines of force of the first permanent magnet 24 and the second permanent magnet 12 in the radial direction of the rotor core, thereby improving the magnetic concentration effect of the motor.

[0077] As shown in Figures 3 and 5 , in one embodiment of the present application, the length between the central axis of the first rotor core 21 and the outer circumference of the first permanent magnet 24 is e, and the length between the central axis of the second rotor core 11 and the end of the second permanent magnet 12 away from the second axial hole 13 is f, where min(e) = f. This arrangement makes it easier for the protrusion 23 of the first rotor core 21 to guide some of the magnetic lines of force of the first permanent magnet 24, thereby reducing the repulsive force between the first rotor assembly 20 and the second rotor assembly 10, making the rotor structure more practical.

[0078] As shown in conjunction with Figures 3 and 5 , in one embodiment of the present application, the length between the central axis of the first rotor core 21 and the outer circumference of the first permanent magnet 24 is e, and the length between the central axis of the second rotor core 11 and the outer circumference of the second rotor core 11 is d, where max(e) ≤ max(d). This arrangement more easily reduces the repulsive force between the first rotor assembly 20 and the second rotor assembly 10, avoiding the problem of mutual repulsion between the multiple rotor assemblies in the rotor structure, which is caused by the use of multiple rotor assemblies to enhance the magnetic concentration effect of the rotor structure.

[0079] Furthermore, there are multiple protrusions 23 , and the multiple protrusions 23 are arranged in pairs along the circumferential direction of the first rotor core 21 .

[0080] As shown in Figures 7 to 10 , in this embodiment, multiple protrusions 23 are arranged in pairs along the circumference of the first rotor core 21. The protrusions 23 can both circumferentially position and secure the first rotor assembly 20. The gaps formed between the paired protrusions 23 can restrict the circumferential movement of the first rotor assembly 20 relative to the second rotor assembly 10. The protrusions 23 of the first rotor core 21 partially divert the magnetic flux of the first permanent magnets 24, thus preventing repulsive forces between the first and second rotor assemblies 20, 10, which could hinder assembly of the rotor structure.

[0081] Furthermore, the first permanent magnet 24 is a monolithic disc-shaped structure, divided into multiple regions of different polarity according to the magnetization direction. This arrangement can reduce the production and assembly costs of the first permanent magnet 24. After magnetization, the different polarity regions are distributed to achieve polarity matching with the second permanent magnet 12.

[0082] Furthermore, projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, the positions of at least one pair of protrusions 23 correspond to the positions of magnetic pole dividing lines of adjacent polarity regions of the first permanent magnet 24 .

[0083] As shown in Figure 6, in this embodiment, the positions of at least one pair of protrusions 23 are projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, and correspond to the positions of the magnetic pole dividing lines of adjacent polarity regions of the first permanent magnet 24. This arrangement can ensure the uniqueness of the polarity region distribution of the first rotor assembly 20.

[0084] Furthermore, two adjacent pairs of protrusions 23 are symmetrically arranged about a center line of one polarity region of the first permanent magnet 24 .

[0085] As shown in Figure 6, two adjacent pairs of protrusions 23 are symmetrically arranged about the center line of a polarity region of the first permanent magnet 24, which helps to guide the magnetic lines of force of each polarity region to the stator, thereby reducing the repulsive force between the first rotor assembly 20 and the second rotor assembly 10 and enhancing the stability of the rotor structure.

[0086] Furthermore, the length of the protrusion 23 extending in the radial direction of the first rotor core 21 is g, and the minimum thickness of the first rotor core 21 in the axial direction is h, wherein g≥0.3*h.

[0087] As shown in Figures 9 and 11, in this embodiment, the length of the protrusion 23 extending radially along the first rotor core 21 is g, and the minimum thickness of the first rotor core 21 in the axial direction is h. The setting of g≥0.3*h is to strengthen the connection strength between the protrusion 23 and the first rotor core 21, limit the minimum size of the radial extension of the protrusion 23, avoid the lack of obvious guiding effect on the magnetic field of the first permanent magnet 24 due to its too small size, and make the working state of the rotor structure more stable.

[0088] Furthermore, projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, the thickness of the second permanent magnet 12 along its magnetizing direction is i, and the spacing width between each pair of protrusions 23 along the tangential direction of the first rotor core 21 is j, where j≥0.25*i.

[0089] As shown in Figures 3 and 9, in this embodiment, the thickness of the second permanent magnet 12 along its magnetization direction is projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, and the spacing width between each pair of protrusions 23 along the tangential direction of the first rotor core 21 is j. j ≥ 0.25 * i can ensure the relative spacing distance between two adjacent protrusions 23. The protrusion 23 can take into account the role of circumferential fixation of the first rotor assembly 20, limit the minimum value of its tangential width, and avoid low reliability of the fixing effect of the protrusion 23.

[0090] Furthermore, the first rotor core 21 is provided with a limiting member 211 , and the first permanent magnet 24 is provided with a limiting structure 241 . The limiting member 211 and the limiting structure 241 are provided correspondingly.

[0091] In another embodiment of the present application, there are multiple limiting members 211 and multiple limiting structures 241, and the multiple limiting members 211 and the multiple limiting structures 241 are arranged in a one-to-one correspondence. This arrangement can make the connection between the first rotor core 21 and the first permanent magnet 24 more stable.

[0092] As shown in Figures 8 and 12, during the assembly of the rotor structure, the limiting member 211 on the first rotor core 21 and the limiting structure 241 on the first permanent magnet 24 cooperate with each other to complete the positioning, preventing the first rotor core 21 and the first permanent magnet 24 from moving and making abnormal noises during the operation of the first rotor assembly 20, thereby reducing the friction and loss of the first rotor assembly 20.

[0093] As shown in combination with Figures 1 and 8, in another embodiment of the present application, the limiting member 211 can be set as a protrusion extending in the axial direction of the first rotor core 21, and the limiting structure 241 is set as a positioning groove. Such a setting replaces the screw and bolt connection in the prior art, reduces the number of parts set, reduces production costs and assembly time costs, and improves the economy of the rotor structure.

[0094] Furthermore, a boss 25 is provided on the side of the first rotor core 21 facing the first permanent magnet 24 , and the boss 25 is provided with a first shaft hole 2412 for the rotating shaft to pass through. An avoidance channel 242 is provided on the first permanent magnet 24 , and part of the boss 25 is inserted into the avoidance channel 242 .

[0095] As shown in Figure 10, in one embodiment of the present application, a boss 25 is provided on the side of the first rotor core 21 facing the first permanent magnet 24, and an avoidance channel 242 is provided on the first permanent magnet 24. The outer peripheral surface of the boss 25 located in the avoidance channel 242 is set at a distance from the side wall of the avoidance channel 242, which can realize the positioning, support, and fixation of the first rotor assembly 20 and the second rotor assembly 10 during the production and assembly process, reduce the assembly difficulty of the rotor structure, and increase the assembly efficiency of the rotor structure.

[0096] Furthermore, the outer circumferential side of the first rotor core 21 is provided with a through slot extending in the axial direction of the first rotor core 21. As shown in FIG8 , the outer circumferential surface of the first rotor core 21 is provided with an axially extending through slot along the circumference of the first rotor core 21. This arrangement can reduce the volume and weight of the first rotor core 21, thereby saving material costs.

[0097] Furthermore, a rotor assembly dynamic balance adjustment structure is provided on the first rotor core 21 .

[0098] In the above embodiment, in order to maintain the dynamic balance of the first rotor assembly 20 in the working state, a rotor assembly dynamic balance adjustment structure is provided on the first rotor core 21 , which can increase the reliability and stability of the first rotor assembly 20 .

[0099] In one embodiment of the present application, the first rotor core 21 and the second rotor core 11 are both made of magnetic conductive materials.

[0100] In another embodiment of the present application, the first rotor core 21 is stamped from magnetically conductive steel sheets, offering advantages such as simple manufacturing, relatively low production costs, a short production cycle, and improved maintenance flexibility. The second rotor core 11 is laminated from silicon steel sheets. Because silicon steel sheets have advantages such as high magnetic permeability, low hysteresis loss, and low coercive force, they can reduce energy loss in the motor and improve its efficiency. Furthermore, silicon steel sheets have excellent mechanical strength and corrosion resistance, and can withstand the vibration and high temperatures experienced during motor operation.

[0101] Furthermore, as shown in FIG13 , a second rotor core lobe 111 is formed between two adjacent magnetic steel slots on the second rotor core 11. When the polarity region of the first permanent magnet 24 disposed axially adjacent to the second rotor core lobe 111 is of the first polarity, the polarity regions of the two second permanent magnets 12 disposed circumferentially adjacent to the second rotor core lobe 111 are also of the first polarity. In another embodiment of the present application, the second rotor core 11 includes a second rotor core lobe 111, and a second rotor core lobe 111 is disposed between two adjacent magnetic steel slots 212. The polarity of the two adjacent magnetic steel slots is the same as the polarity of the first permanent magnet 24 adjacent to the second rotor core lobe 111.

[0102] A preferred implementation method is to alternately magnetize the first permanent magnet 24 along the axial NS poles and the second permanent magnet 12 along the tangential NS poles. At a certain pole, the magnetization directions of both are directed to the second rotor core 11. Under this magnetization method, the magnetic flux of the first permanent magnet 24 and the second permanent magnet 12 can be superimposed, thereby improving the no-load magnetic flux.

[0103] In another embodiment of the present application, the first rotor core 21 and the first permanent magnet 24 are fixedly connected. This arrangement can reduce vibration and abnormal noise generated by the first rotor assembly 20, ensuring smoother and more reliable operation of the rotor structure. In the present application, the method for fixing the first permanent magnet 24 and the first rotor core 21 is not limited to adsorption, adhesion, or mechanical fixation. It is sufficient to ensure that the first permanent magnet 24 and the first rotor core 21 do not move relative to each other.

[0104] In another embodiment of the present application, a motor is provided, including a rotor structure and a stator structure, wherein the rotor structure is the rotor structure in the above embodiment.

[0105] Specifically, the rotor structure includes a first rotor assembly 20, which is arranged in two groups. Each group of first rotor assemblies 20 includes a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. A protrusion 23 extending radially along the first rotor core 21 is provided on the radially outer side of the first rotor core 21. The first rotor core 21 defines a first axial hole 22 for the shaft to pass through. A second rotor assembly 10 includes a second rotor core 11 and a second permanent magnet 12. The second rotor core 11 defines a second axial hole 13. Multiple magnetic steel slots are circumferentially arranged in the second rotor core 11, each of which contains a second permanent magnet 12. The two groups of first rotor assemblies 20 are respectively arranged at both ends of the second rotor assembly 10. The second rotor core 11 is disposed between the first permanent magnets 24 of the two groups of first rotor assemblies 20. The first permanent magnets 24 are disposed between the ends of the second rotor assembly 10 and the first rotor core 21.

[0106] The magnetic lines of force emitted from the axial direction of the first rotor assembly 20 and the magnetic lines of force emitted from the radial direction of the second rotor assembly 10 enter the air gap after being magnetized on the iron core of the rotor structure, which can greatly improve the magnetization effect of the rotor structure. The first rotor assembly 20 is set into two groups, and each group of the first rotor assembly 20 includes a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. The circumference of the first rotor core 21 is provided with a protrusion 23 extending along the circumference of the first rotor core 21, which is used to guide away part of the magnetic lines of force of the first permanent magnet 24, so that the magnetic lines of force directly pass through the air gap and enter the stator, which can reduce the repulsive force between the first rotor assembly 20 and the second rotor assembly 10, and reduce the difficulty of assembly.

[0107] In this embodiment, the rotor structure includes a first rotor assembly 20 and a second rotor assembly 10, which can significantly enhance the magnetic field concentration effect of the rotor structure. The first rotor assembly 20 is provided in two groups, each group of first rotor assemblies 20 including a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. The first rotor core 21 is provided with a protrusion 23 extending along the circumference of the first rotor core 21, which reduces the repulsive force between the rotor assemblies and reduces the difficulty of assembly.

[0108] As shown in Figures 14 to 16, the motor in the above embodiment has a significantly increased magnetic concentration coefficient compared with the prior art, has stronger no-load magnetic properties, and has an air gap magnetic density basically between 0.2mm-0.4mm, which can ensure the stability and efficiency of the motor at the same time.

[0109] From the above description, it can be seen that the above embodiments of the present application achieve the following technical effects:

[0110] The magnetic lines of force emitted from the axial direction of the first rotor assembly 20 and the magnetic lines of force emitted from the radial direction of the second rotor assembly 10 are concentrated on the iron core of the rotor structure and then enter the air gap, which can greatly improve the magnetic concentration effect of the rotor structure.

[0111] The first rotor assembly 20 is provided in two groups, and each group of the first rotor assembly 20 includes a first rotor core 21 and a first permanent magnet 24. The first rotor core 21 and the first permanent magnet 24 are arranged adjacent to each other. A protrusion 23 extending radially along the first rotor core 21 is provided on the radial outer side of the first rotor core 21, which is used to guide away part of the magnetic lines of force of the first permanent magnet 24 so that the magnetic lines of force directly pass through the air gap into the stator, which can reduce the repulsive force between the first rotor assembly 20 and the second rotor assembly 10, and reduce the difficulty of assembly.

[0112] The protrusions 23 provided on the first rotor core 21 help to reduce the repulsive force between the first rotor assembly 20 and the second rotor assembly 10 , thereby lowering the difficulty of assembling the rotor structure and increasing the efficiency of assembling the rotor structure.

[0113] The first permanent magnet 24 is an integrated disc structure, or the first rotor core 21 and the first permanent magnet 24 are fixedly connected. This arrangement can reduce the vibration and abnormal noise generated by the first rotor assembly 20, making the operation of the rotor structure more stable and reliable.

[0114] For ease of description, spatially relative terms such as "above", "above", "on the upper surface", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0115] In addition to the above, it should be noted that references to "one embodiment," "another embodiment," "an embodiment," and the like in this specification refer to specific features, structures, or characteristics described in conjunction with that embodiment as included in at least one embodiment generally described in this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in conjunction with any embodiment, it is intended that such feature, structure, or characteristic, when implemented in conjunction with other embodiments, also fall within the scope of this application.

[0116] In the above embodiments, the description of each embodiment has its own focus. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0117] The above description is merely a preferred embodiment of the present application and is not intended to limit the present application. Various modifications and variations are possible for those skilled in the art. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present application shall be included within the scope of protection of the present application.

Claims

1. A rotor structure, characterized in that, it includes: A first rotor assembly (20), two sets of the first rotor assemblies (20) are provided, each set of the first rotor assemblies (20) includes a first rotor core (21) and a first permanent magnet (24), the first rotor core (21) and the first permanent magnet (24) are arranged adjacent to each other, a protrusion (23) extending radially along the first rotor core (21) is provided on the radially outer side of the first rotor core (21), and a first shaft hole (22) for a rotating shaft to pass through is provided in the first rotor core (21); A second rotor assembly (10), the second rotor assembly (10) includes a second rotor core (11) and a second permanent magnet (12), a second shaft hole (13) is provided in the second rotor core (11), and a plurality of magnet slots are provided in the circumferential direction of the second rotor core (11), and one of the second permanent magnets (12) is respectively provided in each of the magnet slots; The two sets of the first rotor assemblies (20) are respectively arranged at the axial two ends of the second rotor assembly (10), the second rotor core (11) is arranged between the first permanent magnets (24) of the two sets of the first rotor assemblies (20), and the first permanent magnet (24) is arranged between the end of the second rotor assembly (10) and the first rotor core (21).

2. The rotor structure according to claim 1, characterized in that, The protrusion (23) extending radially outward along the first rotor core (21) is one or more.

3. The rotor structure according to claim 2, characterized in that, The number of the protrusions (23) is a, and a / 4 is an integer.

4. The rotor structure according to claim 2, characterized in that, The protrusions (23) are multiple. When projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, the geometric center of the protrusion (23) or the geometric centers of adjacent protrusions (23) are connected to the central axis of the first rotor core (21), and the central angle formed between adjacent connections is b, and the number of pole pairs of the rotor structure is p, wherein, b / (360 / 2p) = b0, and b0 is an integer.

5. The rotor structure according to claim 4, characterized in that, b / (360 / 2p) = b0, and b0 is an odd number.

6. The rotor structure according to claim 1, characterized in that, When projected onto an axial end face of the rotor structure along the axial direction of the rotor structure, the length of the connection line between the central axis of the first rotor core (21) and any point on the outer circle of the first rotor core (21) is c, and the length of the connection line between the central axis of the second rotor core (11) and any point on the outer circle of the second rotor core (11) is d, wherein, max(c) = max(d).

7. The rotor structure according to claim 1, characterized in that, Project along the axial direction of the rotor structure on an axial end face of the rotor structure. The length of the line connecting the center axis of the first rotor core (21) and any point on the outer circle of the first permanent magnet (24) is e. The length between the center axis of the second rotor core (11) and the center point of the end edge of the second permanent magnet (12) away from the second shaft hole (13) is f. The length of the line connecting the center axis of the second rotor core (11) and any point on the outer circle of the second rotor core (11) is d. Wherein, min(e) = f, or max(e) ≤ max(d).

8. The rotor structure according to claim 2, characterized in that there are a plurality of the protrusions (23), and the plurality of the protrusions (23) are arranged in pairs along the circumferential direction of the first rotor core (21).

9. The rotor structure according to claim 1, characterized in that the first permanent magnet (24) is of an integral disc structure and is divided into a plurality of different polarity regions according to the magnetization direction.

10. The rotor structure according to claim 8, characterized in that Project along the axial direction of the rotor structure on an axial end face of the rotor structure. The positions of at least one pair of the protrusions (23) correspond to the positions of the magnetic pole dividing lines of the adjacent polarity regions of the first permanent magnet (24).

11. The rotor structure according to claim 8, characterized in that adjacent pairs of the protrusions (23) are symmetrically arranged with respect to the center line of a polarity region of the first permanent magnet (24).

12. The rotor structure according to claim 1, characterized in that the length of the protrusion (23) extending along the radial direction of the first rotor core (21) is g, and the minimum thickness of the first rotor core (21) in the axial direction is h. Wherein, g ≥ 0.3*h.

13. The rotor structure according to claim 1 or 8, characterized in that Project along the axial direction of the rotor structure on an axial end face of the rotor structure. The thickness of the second permanent magnet (12) along its magnetization direction is i, and the interval width between adjacent protrusions (23) in the tangential direction of the first rotor core (21) is j. Wherein, j ≥ 0.25*i.

14. The rotor structure according to claim 1, characterized in that the first rotor core (21) is provided with a limiting member (211), the first permanent magnet (24) is provided with a limiting structure (241), and the limiting member (211) and the limiting structure (241) are arranged correspondingly.

15. The rotor structure according to claim 14, characterized in that there are a plurality of the limiting members (211), there are a plurality of the limiting structures (241), and the plurality of the limiting members (211) and the plurality of the limiting structures (241) are arranged in one-to-one correspondence.

16. The rotor structure according to claim 11, characterized in that A boss (25) is provided on one side of the first rotor core (21) facing the first permanent magnet (24). An avoidance channel (242) is provided on the first permanent magnet (24), and a part of the boss (25) penetrates through the avoidance channel (242).

17. The rotor structure according to claim 1, characterized in that, a dynamic balance adjustment structure for the rotor assembly is provided on the first rotor core (21).

18. The rotor structure according to claim 1, characterized in that, both the first rotor core (21) and the second rotor core (11) are made of a magnetic conductive material.

19. The rotor structure according to claim 18, characterized in that, the first rotor core (21) is formed by stamping a magnetic conductive steel plate, and the second rotor core (11) is formed by laminating silicon steel sheets.

20. The rotor structure according to claim 9, characterized in that, a second rotor core lobe (111) is formed between two adjacent magnetic steel grooves on the second rotor core (11). When the polar region of the first permanent magnet (24) adjacent to the second rotor core lobe (111) in the axial direction is of the first polarity, the polar regions of the two second permanent magnets (12) adjacent to the second rotor core lobe (111) in the circumferential direction are also of the first polarity.

21. A motor, comprising a rotor structure and a stator structure, characterized in that, the rotor structure is the rotor structure according to any one of claims 1 to 20.

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