Rotor assembly, permanent magnet motor and vehicle
By incorporating cooling channels, radial guide grooves, and axial guide grooves into the rotor assembly, direct cooling of the permanent magnet motor is achieved, solving the problem of low cooling efficiency, improving cooling effect, and reducing production costs.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- UNITED AUTOMOTIVE ELECTRONICS SYST
- Filing Date
- 2025-04-22
- Publication Date
- 2026-04-28
AI Technical Summary
Existing permanent magnet motors have low rotor cooling efficiency, and the cooling medium cannot directly and effectively cool the permanent magnets, resulting in poor cooling performance.
Cooling channels, radial guide grooves, and axial guide grooves are set in the rotor assembly. The cooling medium directly contacts the permanent magnet through these channels, forming a cooling flow path and improving the cooling effect.
By directly cooling the permanent magnet with the cooling medium, the cooling effect is significantly improved, the production process steps and costs are reduced, and the cooling uniformity and the smooth flow of the medium are enhanced.
Smart Images
Figure CN224177982U_ABST
Abstract
Description
Technical Field
[0001] This utility model belongs to the field of permanent magnet motor technology, and in particular relates to a rotor assembly, a permanent magnet motor and a vehicle. Background Technology
[0002] Currently, in order to achieve cooling of permanent magnet motors, a first cooling channel is usually set inside the rotor shaft and a second cooling channel is set inside the rotor core. The first and second cooling channels are connected to achieve cooling of the rotor core, which in turn indirectly cools the permanent magnets on the rotor core that are separated from the second cooling channel. This results in low cooling efficiency. Utility Model Content
[0003] In view of the shortcomings of the prior art described above, the purpose of this utility model is to provide a rotor assembly, a permanent magnet motor, and a vehicle to solve the above problems.
[0004] To achieve the above and other related objectives, this utility model provides a rotor assembly, comprising:
[0005] A rotating shaft, wherein a cooling channel is provided inside the rotating shaft;
[0006] The rotor core assembly includes a first lamination and a second lamination sleeved on the rotating shaft. The first lamination and the second lamination are overlapped. The first lamination has multiple layers of magnetic steel grooves corresponding to each magnetic pole. A permanent magnet is disposed in each of the magnetic steel grooves. A flow gap for cooling medium to flow is provided between the permanent magnet and the side wall of the magnetic steel groove. The second lamination has an axial flow guide groove and a radial flow guide groove corresponding to each magnetic pole. The radial flow guide groove connects the cooling channel and the axial flow guide groove. The axial flow guide groove is opened layer by layer along the multiple layers of magnetic steel grooves corresponding to the magnetic pole and is connected to each layer of magnetic steel grooves.
[0007] Optionally, the rotor assembly further includes:
[0008] A balance disc is disposed on the outer side of both ends of the rotor core assembly along the axial direction. The balance disc is sleeved on the rotating shaft and presses and limits the rotor core assembly. The balance disc is provided with an outlet that communicates with the magnet slot.
[0009] Optionally, the first lamination is distributed on both sides of the second lamination and is arranged in a mirror-symmetrical manner with the second lamination as the axis of symmetry.
[0010] Optionally, the connection position between the axial flow guide groove and the magnet groove is partially misaligned, forming a stepped flow path.
[0011] Optionally, the outermost radius of at least one layer of magnetic steel groove is greater than the outermost radius of the corresponding layer of axial guide groove to form the stepped flow path.
[0012] Optionally, at least one layer of magnetic groove has a radial width greater than the radial width of the corresponding axial flow channel to form the stepped flow path.
[0013] Optionally, the minimum distance between the axial flow guide groove and the rotating shaft in each layer is less than the minimum distance between the corresponding magnet groove and the rotating shaft, and the maximum distance between the axial flow guide groove and the rotating shaft in each layer is less than the maximum distance between the corresponding magnet groove and the rotating shaft, so as to form the stepped flow path.
[0014] Optionally, the radial guide groove contains a straight flow channel, and the axial guide groove is arranged in a mirror-symmetric manner with the axis of the straight flow channel as the axis of symmetry.
[0015] Optionally, from the center direction of the first lamination to the circumferential direction, the magnetic groove is arranged in an arc shape, and the arc length of the two layers of magnetic grooves decreases sequentially.
[0016] Optionally, multiple independent permanent magnets are respectively installed in the magnetic steel groove.
[0017] To achieve the above and other related objectives, this utility model provides a permanent magnet motor, including a stator assembly and the aforementioned rotor assembly.
[0018] To achieve the above-mentioned objectives and other related objectives, this utility model provides a vehicle including the aforementioned permanent magnet motor.
[0019] As described above, the rotor assembly, permanent magnet motor, and vehicle of this invention have the following beneficial effects:
[0020] In this design, the cooling channels, radial guide grooves, axial guide grooves, flow gaps, and outlets form the cooling path for the permanent magnet motor. The cooling medium flows through the cooling channels on the shaft to the radial guide grooves on the second lamination, then through the radial guide grooves to the axial guide grooves, and from there to the flow gap between the magnet slot and the permanent magnet, finally exiting from the outlet of the balance disc. During the cooling process, the permanent magnet is immersed in the cooling path, directly cooled by the cooling medium. Compared to traditional indirect cooling methods, this significantly improves the cooling effect. Because the cooling medium flows into the magnet slot, the radial positioning of the permanent magnet is achieved through the dimensional tolerance between the permanent magnet and the magnet slot, while the axial positioning is achieved through the balance disc. No dispensing or injection molding processes are required to fix the permanent magnet. Attached Figure Description
[0021] Figure 1 This is a cross-sectional schematic diagram of the rotor assembly in an embodiment of the present invention.
[0022] Figure 2 This is a front view of the first lamination in an embodiment of this utility model.
[0023] Figure 3 This is a front view of the second lamination in an embodiment of this utility model. Detailed Implementation
[0024] The reference numerals in the accompanying drawings include:
[0025] Shaft 1, Cooling Channel 101
[0026] First stamping 2, magnet slot 201, first magnet slot 2011, second magnet slot 2012, third magnet slot 2013, center line 202.
[0027] Second lamination 3, radial guide groove 301, axial guide groove 302, first axial guide groove 3021, second axial guide groove 3022, third axial guide groove 3023, axis 303.
[0028] Balance disc 4.
[0029] The following specific embodiments illustrate the implementation of this utility model. Those skilled in the art can easily understand other advantages and effects of this utility model from the content disclosed in this specification.
[0030] Reference Appendix Figures 1-3 As shown, in an exemplary embodiment of this application, a rotor assembly is provided, including:
[0031] Rotary shaft 1, with a cooling channel 101 provided inside the rotating shaft 1;
[0032] The rotor core assembly includes at least one stack of first laminations 2 and one stack of second laminations 3. The first laminations 2 and the second laminations 3 are overlapped and sleeved on the rotating shaft 1. The first laminations 2 are provided with at least two layers of magnetic steel grooves 201 corresponding to each magnetic pole. Permanent magnets are respectively provided in the magnetic steel grooves 201. A flow gap for cooling medium to flow is provided between the permanent magnets and the side wall of the magnetic steel grooves 201. The second laminations 3 are provided with axial flow guide grooves 302 and radial flow guide grooves 301 corresponding to each magnetic pole. The radial flow guide grooves 301 connect the cooling flow channel 101 and the axial flow guide grooves 302. The axial flow guide grooves 302 are opened layer by layer along the multi-layer magnetic steel grooves 201 corresponding to the magnetic pole and are connected to each layer of magnetic steel grooves 201.
[0033] The balance disc 4 is located on the outer side of both ends of the rotor core assembly along the axial direction. The balance disc 4 is sleeved on the rotating shaft 1 and presses and limits the rotor core assembly. The balance disc 4 is provided with an outlet that communicates with the magnet groove 201.
[0034] It should be noted that the magnetic steel trough can be configured with two, three, or more layers as needed.
[0035] For example, each magnetic pole has three layers of magnetic steel groove 201, which can effectively increase the cooling area of the permanent magnet compared to having two layers.
[0036] For example, from the circumference of the first lamination 2 to the center, three layers of arc-shaped magnetic grooves 201 are sequentially arranged corresponding to each magnetic pole, referred to as the first magnetic groove 2011, the second magnetic groove 2012, and the third magnetic groove 2013, respectively. The axial flow guide groove 302 corresponding to the first magnetic groove 2011 is called the first axial flow guide groove 3021, the axial flow guide groove 302 corresponding to the second magnetic groove 2012 is called the second axial flow guide groove 3022, and the axial flow guide groove 302 corresponding to the third magnetic groove 2013 is called the third axial flow guide groove 3023. The first axial flow guide groove 3021, the second axial flow guide groove 3022, and the third axial flow guide groove 3023 are sequentially connected.
[0037] For example, the inlet of the cooling channel 101 is located at one end of the rotating shaft 1, and the outlet of the cooling channel 101 is provided on the rotating shaft 1. The outlet of the cooling channel 101 is located at the position that connects to the radial guide groove 301.
[0038] In this embodiment, the cooling channel 101, radial guide groove 301, axial guide groove 302, flow gap, and outlet form the cooling flow path of the permanent magnet motor. The cooling medium flows through the cooling channel 101 on the rotating shaft 1 to the radial guide groove 301 on the second lamination 3, then flows through the radial guide groove 301 to the axial guide groove 302, and from the axial guide groove 302 to the flow gap between the magnet groove 201 and the permanent magnet, and then flows out from the outlet of the balance disk 4. During the cooling process, the permanent magnet is immersed in the cooling flow path and is directly cooled by the cooling medium. Compared with the traditional indirect cooling of the permanent magnet by the cooling medium, this can effectively improve the cooling effect. Since the cooling medium is introduced into the magnet groove 201, the radial limit of the permanent magnet is achieved by the dimensional tolerance between the permanent magnet and the magnet groove 201, and the axial limit of the permanent magnet is achieved by the balance disk 4. No glue or injection molding process is required to fix the permanent magnet.
[0039] In an exemplary embodiment, the first stamping 2 is distributed on both sides of the second stamping 3 and is arranged in a mirror-symmetrical manner with the second stamping 3 as the axis of symmetry.
[0040] In this embodiment, the first lamination 2 is distributed on both sides of the second lamination 3 and is arranged in a mirror symmetrical manner with the second lamination 3 as the axis of symmetry, so that the second lamination 3 is located in the middle position of the rotor core assembly. In this way, the cooling medium enters from the middle of the rotor core assembly, which can increase the cooling uniformity of the rotor core assembly.
[0041] In one exemplary embodiment, the connection position between the axial flow channel 302 and the magnet channel 201 is partially misaligned, forming a stepped flow path.
[0042] For example, the cooling medium is cooling oil.
[0043] In this embodiment, the stepped flow path is designed to create an axial pressure difference and reduce the flow resistance between the axial flow guide groove 302 and the magnetic groove 201.
[0044] In one exemplary embodiment, the outermost radius of at least one layer of magnetic steel groove 201 is greater than the outermost radius of the corresponding layer of axial flow guide groove 302 to form a stepped flow path.
[0045] For example, the outermost radius of each layer of magnetic steel groove 201 is greater than the outermost radius of the corresponding layer of axial flow guide groove 302 to form a stepped flow path.
[0046] For example, the outermost radius of the first magnetic groove 2011 is denoted as R11, the outermost radius of the second magnetic groove 2012 is denoted as R12, and the outermost radius of the third magnetic groove 2013 is denoted as R13. The outermost radius of the first axial guide groove 3021 is denoted as R21, the outermost radius of the second axial guide groove 3022 is denoted as R22, and the outermost radius of the third axial guide groove 3023 is denoted as R23. Wherein, R11≥R21, R12≥R22, and R13≥R23.
[0047] In an exemplary embodiment, each magnetic pole is symmetrically provided with two sets of magnetic slots along its centerline 202, the centerline 202 coinciding with the diameter of the first lamination. Each set of magnetic slots consists of a first magnetic slot 2011, a second magnetic slot 2012, and a third magnetic slot 2013. The distances between the first magnetic slot 2011, the second magnetic slot 2012, and the third magnetic slot 2013 and the centerline 202 increase sequentially, and the distance W11 between the first magnetic slot 2011 and the centerline 202 is greater than or equal to the distance W21 between the axis 303 of the first axial flow guide slot 3021 and the radial flow guide slot 301, thus forming a stepped flow path.
[0048] In an exemplary embodiment, the width of at least one layer of magnetic groove 201 is greater than or equal to the width of the corresponding layer of axial flow guide groove 302 to form a stepped flow path.
[0049] For example, the width of the first magnetic groove 2011 is denoted as L11, the width of the second magnetic groove 2012 is denoted as L12, and the width of the third magnetic groove 2013 is denoted as L13. The width of the first axial guide groove 3021 is denoted as L21, the width of the second axial guide groove 3022 is denoted as L22, and the width of the third axial guide groove 3023 is denoted as L23. Wherein, L11≥L21, L12≥L22, and L13≥L23.
[0050] In an exemplary embodiment, the minimum distance between each layer of axial guide channel 302 and the rotating shaft 1 is less than the minimum distance between the corresponding magnet channel 201 and the rotating shaft 1, and the maximum distance between each layer of axial guide channel 302 and the rotating shaft 1 is less than the maximum distance between the corresponding magnet channel 201 and the rotating shaft 1.
[0051] In this embodiment, the minimum distance between each layer of axial flow channel 302 and the rotating shaft 1 is less than the minimum distance between the corresponding magnet groove 201 and the rotating shaft 1, and the maximum distance between each layer of axial flow channel 302 and the rotating shaft 1 is less than the maximum distance between the corresponding magnet groove 201 and the rotating shaft 1, so as to form a stepped flow path, so that when the cooling medium flows from the axial flow channel 302 to the magnet groove 201, it tends to flow outward, thereby increasing the smoothness of medium flow.
[0052] For example, the outer radius of the middle portion of the first magnetic trough 2011 is denoted as R14, the outer radius of the middle portion of the second magnetic trough 2012 is denoted as R15, and the outer radius of the middle portion of the third magnetic trough 2013 is denoted as R16. The outer radius of the middle portion of the first axial guide channel 3021 is denoted as R24, the outer radius of the middle portion of the second axial guide channel 3022 is denoted as R25, and the outer radius of the middle portion of the third axial guide channel 3023 is denoted as R26. Wherein, R14 ≥ R24, R15 ≥ R25, and R16 ≥ R26.
[0053] For example, the angle between the side of the first magnet groove 2011 away from the center of the first lamination 201 and the center line 202 is denoted as a16; the angle between the side of the first magnet groove 2011 near the center of the first lamination 201 and the center line 202 is denoted as a15; the angle between the side of the second magnet groove 2012 away from the center of the first lamination 201 and the center line 202 is denoted as a14; the angle between the side of the second magnet groove 2012 near the center of the first lamination 201 and the center line 202 is denoted as a13; the angle between the side of the third magnet groove 2013 away from the center of the first lamination 201 and the center line 202 is denoted as a12; and the angle between the side of the third magnet groove 2013 near the center of the first lamination 201 and the center line 202 is denoted as a11. The angle between the side of the first axial guide channel 3021 away from the center of the second lamination 202 and the axis 303 (i.e., the axis of the radial guide channel 301) is denoted as a26. The angle between the side of the first axial guide channel 3021 near the center of the second lamination 202 and the axis 303 is denoted as a25. The angle between the side of the second axial guide channel 3022 away from the center of the second lamination 202 and the axis 303 is denoted as a24. The angle between the side of the second axial guide channel 3022 near the center of the second lamination 202 and the axis 303 is denoted as a23. The angle between the side of the third axial guide channel 3023 away from the center of the second lamination 202 and the axis 303 is denoted as a22. The angle between the side of the third axial guide channel 3023 near the center of the second lamination 202 and the axis 303 is denoted as a21. Where a16≤a26≤(90-(360 / 2p) / 2), a15≥a25, a14≤a24, a13≥a23, a12≤a22, a11≥a21, and P is the number of pole pairs of the permanent magnet motor.
[0054] For example, the minimum distance between the first magnetic groove 2011 and the rotating shaft 1 is denoted as H2, and the minimum distance between the first axial guide groove 3021 and the rotating shaft 1 is denoted as H1, where H2 > H1.
[0055] For example, the maximum distance between the first magnetic steel groove 2011 and the rotating shaft 1 is denoted as H4, and the maximum distance between the first magnetic steel groove 2011 and the axial guide groove 302 and the rotating shaft 1 is denoted as H3, where H4 > H3.
[0056] In an exemplary embodiment, two layers of arc-shaped magnetic grooves 201 are provided from the center direction of the first lamination 2 to the circumferential direction, and the arc lengths of the two layers of magnetic grooves 201 decrease sequentially.
[0057] In this embodiment, the curvature of the first magnet groove 2011, the second magnet groove 2012, and the third magnet groove 2013 increases sequentially.
[0058] In one exemplary embodiment, multiple independent permanent magnets are respectively disposed in the magnetic steel groove 201.
[0059] It should be noted that traditional permanent magnet motors use permanent magnets of different specifications, which necessitates the production line to prepare different tooling fixtures and material control measures for each type of permanent magnet. In this embodiment, the permanent magnets are manufactured in segmented form, with each segment having the same shape and size. Compared to traditional permanent magnet motors using permanent magnets of different sizes, this eliminates the need for tooling fixtures for different sizes of permanent magnets on the production line, as well as different material control measures. There are no special fixing connections between each permanent magnet segment, reducing process steps and production costs. Using segmented permanent magnets for each pole reduces permanent magnet motor losses, improves motor efficiency, and increases the contact area between the permanent magnet and the cooling medium.
[0060] In an exemplary embodiment, the radial guide groove 301 contains a straight flow channel, and the axial guide groove 302 is arranged in a mirror-symmetric manner with the axis 303 of the straight flow channel as the axis of symmetry.
[0061] In this embodiment, the axial flow channel 302 is adapted to the shape of the magnet channel 201. The axial flow channel 302 is mirror-symmetrically arranged with the axis 303 of the straight flow channel as the axis of symmetry, so that the cooling medium can flow more evenly into the magnet channel 201 and increase the cooling effect.
[0062] In one exemplary embodiment of this application, a permanent magnet motor is provided, including a stator assembly and the aforementioned rotor assembly.
[0063] In this embodiment, the rotor assembly described above is applied to a permanent magnet motor, which helps to increase the cooling effect of the permanent magnet motor.
[0064] In an exemplary embodiment of this application, a vehicle is provided that includes the aforementioned permanent magnet motor to effectively increase the cooling effect, thereby ensuring the performance of the permanent magnet motor while effectively reducing production costs.
[0065] The above embodiments are merely illustrative of the principles and effects of this utility model and are not intended to limit the scope of this utility model. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of this utility model. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in this utility model should still be covered by the claims of this utility model.
Claims
1. A rotor assembly, characterized in that, include: A rotating shaft, wherein a cooling channel is provided inside the rotating shaft; The rotor core assembly includes at least one stack of first laminations and one stack of second laminations. The first laminations and the second laminations are overlapped and fitted onto the rotating shaft. The first laminations have at least two layers of magnetic steel grooves corresponding to each magnetic pole. A permanent magnet is disposed in each of the magnetic steel grooves. A flow gap for cooling medium to flow is provided between the permanent magnet and the side wall of the magnetic steel groove. The second laminations have axial flow guide grooves and radial flow guide grooves corresponding to each magnetic pole. The radial flow guide grooves connect the cooling channel and the axial flow guide grooves. The axial flow guide grooves are opened layer by layer along the multi-layer magnetic steel grooves corresponding to the magnetic pole and are connected to each layer of magnetic steel grooves.
2. The rotor assembly according to claim 1, characterized in that, The rotor assembly also includes: A balance disc is disposed on the outer side of both ends of the rotor core assembly along the axial direction. The balance disc is sleeved on the rotating shaft and presses and limits the rotor core assembly. The balance disc is provided with an outlet that communicates with the magnet slot.
3. The rotor assembly according to claim 1, characterized in that, The first lamination is distributed on both sides of the second lamination and is arranged in a mirror symmetrical manner with the second lamination as the axis of symmetry.
4. The rotor assembly according to claim 1, characterized in that, The connection between the axial flow channel and the magnet channel is partially misaligned, forming a stepped flow path.
5. The rotor assembly according to claim 4, characterized in that, The outermost radius of at least one layer of magnetic steel groove is greater than the outermost radius of the corresponding layer of axial guide groove to form the stepped flow path.
6. The rotor assembly according to claim 4, characterized in that, At least one layer of magnetic steel groove has a radial width greater than the radial width of the corresponding axial flow channel to form the stepped flow path.
7. The rotor assembly according to claim 4, characterized in that, The minimum distance between the axial flow guide groove and the rotating shaft in each layer is less than the minimum distance between the corresponding magnet groove and the rotating shaft, and the maximum distance between the axial flow guide groove and the rotating shaft in each layer is less than the maximum distance between the corresponding magnet groove and the rotating shaft, so as to form the stepped flow path.
8. The rotor assembly according to claim 1, characterized in that, The radial guide groove contains a straight flow channel, and the axial guide groove is arranged in a mirror-symmetric manner with the axis of the straight flow channel as the axis of symmetry.
9. The rotor assembly according to claim 1, characterized in that, From the center of the first lamination to the circumference, the magnetic groove is arc-shaped, and the arc length of the two layers of magnetic grooves decreases sequentially.
10. The rotor assembly according to any one of claims 1 to 9, characterized in that, The magnetic groove is equipped with multiple independent permanent magnets.
11. A permanent magnet motor, characterized in that, It includes a stator assembly and a rotor assembly as described in any one of claims 1 to 10.
12. A vehicle, characterized in that, Including the permanent magnet motor as described in claim 11.