Permanent magnet motor rotor and permanent magnet motor

Abstract

This application discloses a permanent magnet motor rotor and a permanent magnet motor. The permanent magnet motor rotor includes: a shaft; a rotor core comprising several segments evenly distributed circumferentially along the shaft; several permanent magnets; each segment is positioned with an adjacent permanent magnet; and a frame comprising at least one first positioning ring and several positioning strips distributed circumferentially along the first positioning ring. The first positioning ring is fitted onto the shaft and has an interference fit with it. Each positioning strip is connected at one end to the first positioning ring and inserted at the other end into the side of the rotor core relatively close to the shaft. The shaft, rotor core, permanent magnets, and frame are integrally cast from aluminum. This application aims to solve the technical problem of improving the positioning accuracy of segmented rotors and reducing manufacturing costs.

Description

Technical Field

[0001] This application relates to the field of automotive technology, and more particularly to a permanent magnet motor rotor and a permanent magnet motor. Background Technology

[0002] Permanent magnet motor rotors typically employ a cast aluminum rotor structure. A typical forming process involves stacking rotor cores and then filling the rotor slots with molten aluminum using a casting process, forming a conductive cage-like structure that simultaneously positions and fixes the magnets. Currently, most common cast aluminum rotors are frameless support structures, meaning they lack an independent reinforcing or positioning frame and rely entirely on the stacked core laminations and the cast aluminum itself to maintain their shape. For magnet fixing, existing technologies often employ adhesive bonding or injection molding. After the magnets are attached to the rotor surface or embedded in the slots, circumferential and axial positioning is achieved through adhesive curing or injection molding material filling.

[0003] However, the aforementioned traditional structures and processes have significant shortcomings. Firstly, after casting, the aluminum rotor requires a cooling process. Due to the difference in thermal expansion coefficients between aluminum and silicon steel sheets, and the lack of internal support, uneven deformation of the rotor is easily caused during the release of internal stress. This deformation directly affects the assembly and positioning accuracy of the segmented rotor structure, causing the relative positions of the magnetic poles to deviate from the design values, resulting in a large error between the actual size of the motor's air gap and the theoretically calculated value. Uneven air gap can lead to problems such as air gap magnetic flux distortion, increased torque fluctuations, and decreased efficiency, severely impacting motor performance. Secondly, while using dispensing or injection molding to fix the magnets can meet basic bonding and encapsulation requirements, adhesives require precise application and have long curing times, and injection molding requires specialized molds and equipment. Both methods complicate the manufacturing process, increase material consumption, and raise overall production costs, hindering cost control in large-scale production. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a permanent magnet motor rotor and a permanent magnet motor to solve the technical problem of how to improve the positioning accuracy of the segmented rotor and reduce manufacturing costs.

[0005] In a first aspect, this application provides a permanent magnet motor rotor, comprising: Shaft; The rotor core comprises several segments evenly distributed circumferentially along the shaft. A plurality of permanent magnets; each of the segments is provided with a permanent magnet between each of the adjacent segments; The frame includes at least one first positioning ring and a plurality of positioning strips distributed circumferentially along the first positioning ring; the first positioning ring is sleeved on the rotating shaft and is interference-fitted with the rotating shaft; each positioning strip is connected at one end to the first positioning ring and at the other end to the side of the rotor core that is relatively close to the rotating shaft. The rotor core, the permanent magnet, and the frame are then integrally cast in aluminum.

[0006] In at least some embodiments of this application, The number of positioning strips on each of the first positioning rings matches the number of segments; the positioning strips are arranged radially along the axis of rotation, and each positioning strip is connected to one of the segments.

[0007] In at least some embodiments of this application, The skeleton also includes at least one second positioning ring; the second positioning ring is sleeved on the rotating shaft and is alternately distributed with the first positioning ring along the axial direction of the rotating shaft; The adjacent second positioning rings are spaced at the same distance from the first positioning rings along the axial direction of the rotating shaft.

[0008] In at least some embodiments of this application, The first positioning ring has at least two, and the distribution of the at least two first positioning rings is symmetrical about the mid-section of the rotor core in the radial direction of the shaft.

[0009] In at least some embodiments of this application, The number of positioning strips on at least two of the first positioning rings is the same, and they are set with a relative oblique angle in the circumferential direction.

[0010] In at least some embodiments of this application, The rotor core has an aluminum cladding layer formed by casting aluminum on the side relatively away from the rotating shaft; The gaps between all rotor cores and the permanent magnets are filled with aluminum material by cast aluminum.

[0011] In at least some embodiments of this application, The rotor core has dynamic balancing layers on both sides of the shaft circumferentially; the dynamic balancing layers are formed by aluminum casting.

[0012] In at least some embodiments of this application, Both the first positioning ring and the positioning strip are made of steel.

[0013] In a second aspect, this application provides a permanent magnet motor, including a permanent magnet motor rotor as described in any of the first aspects.

[0014] The above-described one or more embodiments of this application have at least one or more of the following beneficial effects: In implementing the technical solution of this application, a positioning frame is embedded between the shaft and the rotor core to provide internal support for the cast aluminum rotor. This frame effectively constrains the internal stress release path during the cooling stage, suppresses uneven rotor deformation, thereby improving the positioning accuracy of the segmented rotor, making the air gap size closer to the ideal design, and enhancing motor operating performance. Simultaneously, this application employs integral casting of aluminum, with the permanent magnet directly encapsulated and fixed by the molten aluminum during the casting process, eliminating the need for adhesive dispensing or injection molding. This avoids problems such as long adhesive curing times and the need for specialized molds, while also reducing material and equipment investment, significantly lowering the process cost of fixing the permanent magnet.

[0015] 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

[0016] The disclosure of this application will become more readily understood with reference to the accompanying drawings. It will be readily understood by those skilled in the art that these drawings are for illustrative purposes only and are not intended to limit the scope of protection of this application. Furthermore, similar numbers in the drawings are used to denote similar components, wherein: Figure 1 This is a three-dimensional structural diagram of the assembly of a permanent magnet motor rotor according to one embodiment of this application; Figure 2 This is a three-dimensional structural diagram of the cast aluminum rotor of a permanent magnet motor according to one embodiment of this application; Figure 3 This is a top view of the rotor structure of a permanent magnet motor according to one embodiment of this application; Figure 4 This is a schematic diagram of the positioning ring distribution structure according to one embodiment of this application; Figure 5 This is a top view of the positioning strip arrangement according to one embodiment of this application; Figure 6 This is a top view of the cast aluminum structure of a permanent magnet motor rotor according to one embodiment of this application; Figure 7 This is a side view of the permanent magnet motor rotor with an added dynamic balancing layer, according to one embodiment of this application.

[0017] Explanation of reference numerals in the attached figures: 100. Shaft; 200. Rotor core; 201. Segment; 202. Aluminum cladding layer; 203. Aluminum material; 300. Permanent magnet; 400. Frame; 401. First positioning ring; 402. Positioning bar; 403. Second positioning ring; 500. Dynamic balancing layer. Detailed Implementation

[0018] Some embodiments of this application are described below with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of this application and are not intended to limit the scope of protection of this application.

[0019] See appendix Figure 1 and Figure 2 In one or more embodiments, a permanent magnet motor rotor of this application includes: Shaft 100; The rotor core 200 includes several segments 201 that are evenly distributed circumferentially along the shaft 100; Several permanent magnets 300; a permanent magnet 300 is provided between each segment 201 and the adjacent segment 201; The frame 400 includes at least one first positioning ring 401 and a plurality of positioning strips 402 distributed circumferentially along the first positioning ring 401; the first positioning ring 401 is sleeved on the rotating shaft 100 and is interference-fitted with the rotating shaft 100; each positioning strip 402 is connected at one end to the first positioning ring 401 and inserted at the other end into the side of the rotor core 200 that is relatively close to the rotating shaft 100. After assembly, the rotor core 200, permanent magnet 300, and frame 400 are integrally formed by cast aluminum. This solution can also extend the casting of aluminum to the rotor shaft, or the shaft 100 and frame 400 can be set as one piece, which can be flexibly set by those skilled in the art according to the load and disclosure.

[0020] It is understandable that the segments 201 of the rotor core 200 and the permanent magnets 300 are alternately spliced ​​together, connected end to end in the circumferential direction of the rotating shaft 100. To ensure the positional accuracy of the rotor core 200 and the permanent magnets 300, an embedded frame 400 is used. The frame 400 is interference-fitted with the rotating shaft 100 through the inner side of the first positioning ring 401, forming a relatively fixed positioning structure. The first positioning ring 401 is inserted into the segments 201 of the rotor core 200 through positioning strips 402 relative to the outer side of the rotating shaft 100, forming a fixed structure. Finally, all components (including the rotor core 200, permanent magnets 300, and frame 400) are cast together using an aluminum casting process to form an integral rotor structure.

[0021] In the embodiments of this application, a positioning frame 400 is embedded between the rotating shaft 100 and the rotor core 200 to provide internal support for the cast aluminum rotor. During the cooling stage, this frame 400 effectively constrains the internal stress release path, suppresses uneven rotor deformation, thereby improving the positioning accuracy of the segmented rotor, making the air gap size closer to the ideal design, and enhancing motor operating performance. Simultaneously, this application employs integral casting of aluminum, with the permanent magnet 300 directly encapsulated and fixed by the molten aluminum during the casting process, eliminating the need for adhesive dispensing or injection molding. This avoids problems such as long adhesive curing times and the need for specialized molds, while also reducing material and equipment investment, significantly lowering the fixing process cost of the permanent magnet 300. In one embodiment, reference Figure 3 The number of positioning bars 402 on each first positioning ring 401 matches the number of segments 201, that is, the number of positioning bars 402 matches the number of rotor poles; the positioning bars 402 are arranged radially along the shaft, and each positioning bar 402 is connected to a segment 201, forming a stable support for each segment 201.

[0022] In one specific implementation, refer to Figures 2-4 The frame 400 also includes at least one second positioning ring 403; the second positioning ring 403 is sleeved on the rotating shaft 100 and alternately distributed with the first positioning ring 401 along the axial direction of the rotating shaft 100; the axial spacing between adjacent second positioning rings 403 and first positioning rings 401 is consistent. Specifically, the alternating distribution of the second positioning rings 403 and first positioning rings 401 ensures that the axial spacing of adjacent first positioning rings 401 is consistent, thereby improving the stability of the positioning strip 402 and further enhancing the support and stability effect on the rotor core 200. Adjacent second positioning rings 403 and first positioning rings 401 may or may not be in contact, as long as they are arranged at equal intervals. The number of first positioning rings 401 and second positioning rings 403 is determined by the height of the rotor core 200 along the axial direction of the rotating shaft 100, and the axial arrangement range of the first positioning rings 401 and second positioning rings 403 corresponds to the axial height range of the rotor core 200 along the rotating shaft 100.

[0023] In one specific embodiment, there are at least two first positioning rings 401, and the distribution positions of the at least two first positioning rings 401 are about the middle section of the rotor core 200 in the radial direction of the shaft 100 (reference). Figure 4 (The dashed line in the middle) is symmetrical. The symmetrical arrangement of the first positioning ring 401 ensures uniform force distribution at each point, further improving the stability of the rotor core 200 support.

[0024] In one embodiment, reference Figure 1 , Figure 4 and Figure 5Because the rotor magnet has skewed poles, to accommodate this skewed pole, at least two first positioning rings 401 have the same number of positioning strips 402, which are arranged one-to-one in the axial direction of the rotating shaft 100, and the positioning strips 402 on adjacent positioning rings 401 in the circumferential direction have a skewed pole angle α. The permanent magnet of the motor is skewed by an angle in space; this amount of skew is the skewed pole angle α. Considering the skewed pole, rotating the two first positioning rings 401, which are arranged vertically along the axial direction of the rotating shaft 100, by an angle can achieve skewed pole angles α such as "straight skew," "V-shaped skew," and "Z-shaped skew." In one embodiment, reference Figure 2 and Figure 6 After the rotor core 200, permanent magnet 300, and frame 400 are assembled, they are placed in a mold and molten aluminum is injected to form a single piece. The gap between the permanent magnet 300 and the rotor core 200 will be filled with molten aluminum (forming aluminum material 203 after molding), and the outer rotor surface of the rotor core 200 will also be covered with molten aluminum to form an aluminum cladding layer 202. Furthermore, after molding, if the dimensional accuracy of the outer surface of the rotor core 200 is not good, it can be precision machined to improve the rotor accuracy. The inner side is interference-fitted with the first positioning ring 401 and the rotating shaft 100 to prevent the first positioning ring 401 from loosening and failing under stress during machining.

[0025] like Figure 6 In one embodiment shown, the positioning bar 402 is designed as a positioning ring on the side near segment 201 to better position and support segment 201 and magnet 300.

[0026] In one embodiment, reference Figure 7 The rotor core 200 has dynamic balancing layers 500 on both sides of the rotating shaft 100 in the circumferential direction; the dynamic balancing layers 500 are formed by aluminum casting. In existing rotor structures, if dynamic balancing is required, a separate dynamic balancing plate needs to be installed, leading to complex installation processes and increased costs. However, in this embodiment, during aluminum casting, molten aluminum can be directly poured onto both ends of the rotor core 200 to form an integral shape with the rotor core 200. Furthermore, the pouring height of the dynamic balancing layer 500 can be adjusted as needed, eliminating the need for additional grinding of the dynamic balancing plate, thus reducing process complexity and unnecessary material, significantly lowering process costs.

[0027] In one or more of the above embodiments, the skeleton 400 is made of steel, that is, the first positioning ring 401, the positioning strip 402 and the second positioning ring 403 are all made of steel, to ensure the strength of the skeleton 400.

[0028] Based on the above implementation methods, refer to Figures 1-7An optional manufacturing process for the permanent magnet motor rotor of this application includes: assembling a frame 400 on a rotating shaft 100, including placing a first positioning ring 401 and a second positioning ring 403 at equal intervals on the rotating shaft 100 and interfering with the rotating shaft 100; arranging segments 201 of the rotor core 200 and permanent magnets 300 alternately along the circumference of the rotating shaft 100, and inserting positioning strips 402 into the segments 201 one by one; after assembly, placing it in a mold, injecting molten aluminum for casting, thereby forming an integrally formed rotor. Further, if dynamic balancing is required, aluminum is cast on both sides of the rotor core 200 to form a dynamic balancing layer 500.

[0029] Furthermore, this application provides a permanent magnet motor, including a permanent magnet motor rotor as described above.

[0030] 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.

[0031] 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 at least one of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0032] Although embodiments of this application have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting this application. Those skilled in the art can make changes, modifications, substitutions and variations to the above embodiments within the scope of this application.

Claims

1. A permanent magnet motor rotor, characterized in that, include: Shaft; The rotor core comprises several segments evenly distributed circumferentially along the shaft. A plurality of permanent magnets; each of the segments is provided with a permanent magnet between each of the adjacent segments; The frame includes at least one first positioning ring and a plurality of positioning strips distributed circumferentially along the first positioning ring; the first positioning ring is sleeved on the rotating shaft and is interference-fitted with the rotating shaft; each positioning strip is connected at one end to the first positioning ring and at the other end to the side of the rotor core that is relatively close to the rotating shaft. The rotor core, the permanent magnet, and the frame are assembled and integrally cast in aluminum.

2. The permanent magnet motor rotor according to claim 1, characterized in that, The number of positioning strips on each of the first positioning rings matches the number of segments; the positioning strips are arranged radially along the axis of rotation, and each positioning strip is connected to one of the segments.

3. The permanent magnet motor rotor according to claim 1, characterized in that, The skeleton also includes at least one second positioning ring; the second positioning ring is sleeved on the rotating shaft and is alternately distributed with the first positioning ring along the axial direction of the rotating shaft; The adjacent second positioning rings are spaced at the same distance from the first positioning rings along the axial direction of the rotating shaft.

4. The permanent magnet motor rotor according to claim 1 or 3, characterized in that, The first positioning ring has at least two, and the distribution of the at least two first positioning rings is symmetrical about the mid-section of the rotor core in the radial direction of the shaft.

5. The permanent magnet motor rotor according to claim 4, characterized in that, The number of positioning strips on at least two of the first positioning rings is the same, and they have a relative oblique angle in the circumferential direction.

6. The permanent magnet motor rotor according to claim 1, characterized in that, The rotor core has an aluminum cladding layer formed by casting aluminum on the side relatively away from the rotating shaft; The gaps between all rotor cores and the permanent magnets are filled with aluminum material by cast aluminum.

7. The permanent magnet motor rotor according to claim 1, characterized in that, The rotor core has dynamic balancing layers on both sides of the shaft circumferentially; the dynamic balancing layers are formed by aluminum casting.

8. The permanent magnet motor rotor according to claim 1, characterized in that, Both the first positioning ring and the positioning strip are made of steel.

9. A permanent magnet motor, characterized in that, Includes a permanent magnet motor rotor as described in any one of claims 1-8.

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