Rotor assemblies, motors, and electric vehicles

Abstract

This application relates to a rotor assembly, a motor, and an electric vehicle. The rotor assembly includes an annular rotor and a plurality of magnets fixed to the inner ring of the annular rotor. Between adjacent magnets, a flowing substance that can be magnetically attracted under the influence of its magnetic field is gathered. The flowing substance has two opposing outer sides along the axial direction of the annular rotor, at least one of which is a space. And / or at least one of the magnets can be mounted from one side of the inner ring of the annular rotor along the axial direction of the annular rotor. The rotor assembly of this application improves heat transfer between the rotor assembly and the stator by gathering a flowing substance that can be magnetically attracted under the influence of its magnetic field between adjacent magnets on the annular rotor, thereby ensuring good heat dissipation of the motor.

Description

Technical Field

[0001] This application relates to the field of motor technology, and more specifically, to a rotor assembly, a motor having the rotor assembly, and an electric vehicle having the motor. Background Technology

[0002] The information provided in this section is for the purpose of generally presenting the background of this disclosure. To the extent described in this section, the work of the currently named inventors and aspects of the description that may not constitute prior art at the time of filing are neither explicitly nor implicitly considered to be prior art of this disclosure.

[0003] The electric motor drive system is the core system of an electric vehicle, offering smooth transmission and high efficiency. The electric motor is the core component of the electric motor drive system. Because electric motors, especially hub motors, are external rotor motors, with the stator surrounded by the rotor, and because there is an air gap between the stator and rotor, and air has poor thermal conductivity, the heat generated during the operation of the hub motor cannot be effectively dissipated, thus affecting the operating efficiency of the hub motor. Utility Model Content

[0004] According to this application, a rotor assembly is provided, the rotor assembly including an annular rotor and a plurality of magnets fixed at the inner ring of the annular rotor, wherein a flowing substance that can be magnetically attracted under the action of its magnetic field is gathered between two adjacent magnets, wherein the flowing substance has two opposing outer sides in the axial direction of the annular rotor, at least one of the outer sides being space; and / or at least one of the plurality of magnets can be mounted from one side of the inner ring of the annular rotor to the inner ring of the annular rotor along the axial direction of the annular rotor.

[0005] Optionally, in the rotor assembly as described above, the magnetically attractable fluid is a magnetofluid.

[0006] Optionally, in the rotor assembly as described above, the plurality of magnets are square or tile-shaped permanent magnets.

[0007] Optionally, in the rotor assembly as described above, the inner ring of the annular rotor is provided with a mounting groove for mounting at least one of the plurality of magnets.

[0008] Optionally, in the rotor assembly as described above, the plurality of magnets are of the same size and are uniformly arranged along the circumference of the annular rotor at the inner ring of the annular rotor.

[0009] Optionally, in the rotor assembly as described above, the plurality of magnets are fixed to the inner ring of the annular rotor by adhesive bonding.

[0010] Optionally, in the rotor assembly as described above, the magnetofluid comprises a magnetic material, which includes one or more of the following: iron, cobalt, or nickel and their alloys.

[0011] Furthermore, according to this application, an electric motor is also provided, the electric motor being provided with the aforementioned rotor assembly, the electric motor including a stator, the stator being coaxially disposed with an annular rotor of the rotor assembly and the annular rotor being located outside the stator.

[0012] In addition, according to this application, there is also an electric vehicle equipped with the above-mentioned motor, the motor being fixed to the frame via an axle, the electric vehicle including spokes, one end of the spokes being fixed to a wheel rim, and the other end being fixed to the motor.

[0013] Optionally, in the electric vehicle described above, the electric vehicle is an electric motorcycle or an electric bicycle.

[0014] It is understood that the rotor assembly of this application uses a magnetically attractable fluid material, which helps to quickly dissipate heat between the stator and rotor assembly, thereby improving the heat exchange efficiency between the external air and the motor, and thus improving the heat dissipation efficiency of the motor, resulting in better motor performance, smoother operation and longer service life. Attached Figure Description

[0015] 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:

[0016] Figure 1 An exemplary schematic diagram of the rotor assembly disclosed in this application is shown; and

[0017] Figure 2 An exemplary schematic diagram of the structure of a single magnet of the rotor assembly disclosed in this application is shown. Detailed Implementation

[0018] To make the above-mentioned objectives, features, and advantages of this application more apparent and understandable, the specific embodiments of this application will be described in detail below with reference to the accompanying drawings. First, it should be noted that the directional terms such as up, down, left, right, front, back, inner, outer, top, and bottom mentioned or possibly used in this specification are defined relative to the structures shown in the accompanying drawings. They are relative concepts and may therefore vary depending on their location and usage. Therefore, these or other directional terms should not be interpreted as restrictive terms.

[0019] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, "multiple" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0020] In the description of this application, it should also be noted that, unless otherwise expressly specified and limited, the terms "set up," "install," "connect," and "link" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.

[0021] Figure 1 The structure of a rotor assembly according to this application is shown. The rotor assembly includes an annular rotor 100 and a plurality of magnets 110 fixedly connected to the inner ring of the annular rotor 100, for example, the plurality of magnets 110 being fixed to the inner ring of the annular rotor 100 by adhesive bonding. The annular rotor 100 is made of materials with magnetic permeability, such as steel, iron, and silicon steel sheets, and is typically used in external rotor motors. At least one of the plurality of magnets 110 has an outer surface set as a plane A, i.e., a smooth and flat planar structure; for example, the plurality of magnets 110 are square permanent magnets, such as... Figure 2As shown. Of course, those skilled in the art will readily understand that, in addition to the outer surface of at least one magnet 110 being a plane A, the outer surface of at least one magnet 110 can also be a continuous arcuate surface along the circumference of the annular rotor 100. Herein, the term "arcuate surface" refers to a surface formed by rotating a regular curve about an axis. Specifically, the plurality of magnets 110 can also be tile-shaped permanent magnets. Furthermore, a flowing substance 120, which can be magnetically attracted under the influence of its magnetic field, is gathered between two adjacent magnets 110. When the motor is not operating, the flowing substance 120 is gathered between two adjacent magnets 110; while when the motor is operating, the flowing substance 120 is flowable, meaning that the flowing substance 120 may flow from the annular rotor 100 to its internal stator under electromagnetic influence. Furthermore, in the axial direction of the annular rotor 100, the flowing substance 120 has two opposing outer sides, at least one of which is space. In this document, the term "space" refers to a location on at least one outer side of the flowing material 120 along the axial direction of the annular rotor 100 where no enclosure or obstruction structure exists. At least one of the plurality of magnets 110 can be mounted from one side of the inner ring of the annular rotor 100 to the inner ring of the annular rotor 100 along the axial direction of the annular rotor 100. For example, one side or all of the surface of the inner ring of the annular rotor 100 is a smooth, continuous cylindrical surface. The rotor assembly according to this application gathers magnetically attractable flowing material between adjacent magnets on the annular rotor. This flowing material, as a colloidal liquid, has superior thermal conductivity, absorbing heat from the rotor assembly and stator and rapidly dissipating it into the air, significantly improving the heat dissipation performance of the motor.

[0022] In other optional embodiments, in conjunction with the above embodiments, the magnetically attractable fluid 120 can be a magnetic fluid. For example, the magnetic fluid includes magnetic materials, which include one or more of the following: iron, cobalt, or nickel, and their alloys. It should be noted that the magnetic fluid possesses both the fluidity of a liquid and the magnetism of a solid magnetic material; it is a stable colloidal liquid composed of magnetic solid particles with a diameter on the nanometer scale (below 10 nanometers), a carrier liquid (also called a medium), and a surfactant. This fluid has no magnetic attraction when static, but exhibits magnetism when an external magnetic field is applied.

[0023] For ease of manufacture, the plurality of magnets 110 may be configured to be of the same size and uniformly arranged along the circumference of the annular rotor 100 within the inner ring of the annular rotor 100, such as... Figure 1 As shown. As an alternative, the inner ring of the annular rotor 100 is provided with a mounting groove for mounting at least one of the plurality of magnets 110.

[0024] In addition, this application also provides an electric motor (not shown) equipped with the aforementioned rotor assembly, and the motor includes a stator (not shown), which is coaxially arranged with the annular rotor 100 of the rotor assembly and the annular rotor 100 is located outside the stator. Because the distance between the stator and the annular rotor 100 is very close, the heat generated by the stator during operation is easily conducted to the rotor assembly through the aforementioned magnetically attractable fluid, thereby dissipating the heat through the rotor assembly. This prevents the internal temperature of the motor from becoming too high, resulting in good performance and stable and reliable operation.

[0025] Furthermore, this application also provides an electric vehicle (not shown) equipped with the aforementioned motor, such as a hub motor. The motor is fixed to the frame via an axle. The electric vehicle includes spokes, one end of which is fixed to a rim, and the other end to the motor. The electric vehicle is, for example, an electric motorcycle or an electric bicycle. The technical improvements and beneficial effects of the motor are the same as those described above, therefore, a detailed description of the electric vehicle is not provided here.

[0026] The foregoing has provided several specific embodiments to illustrate the rotor assembly, motor, and electric vehicle of this application. These examples are for illustrative purposes only and are not intended to limit the scope of this application. Various modifications and improvements can be made by those skilled in the art without departing from the spirit and scope of this application. Therefore, all equivalent technical solutions should fall within the scope of this application and be defined by the claims of this application.

Claims

1. A rotor assembly comprising a ring rotor (100) and a plurality of magnets (110) fixed at an inner circumference of the ring rotor (100), characterized in that, Between two adjacent magnets (110) of the plurality of magnets (110) there is a flow material (120) that can be magnetically attracted under the action of its magnetic field, wherein, in the axial direction of the annular rotor (100), the flow material (120) has two opposite outer sides, at least one of the outer sides being space; and / or at least one of the plurality of magnets (110) can be installed from the inner ring side of the annular rotor (100) to the inner ring of the annular rotor (100) along the axial direction of the annular rotor (100).

2. The rotor assembly according to claim 1, characterized in that, The magnetically attracted fluid (120) is a magnetofluid.

3. The rotor assembly according to claim 2, characterized in that, The plurality of magnets (110) are square or tile-shaped permanent magnets.

4. The rotor assembly according to any one of claims 1-3, characterized in that, The inner ring of the annular rotor (100) is provided with a mounting groove for mounting at least one of the plurality of magnets (110).

5. The rotor assembly according to any one of claims 1-3, characterized in that, The plurality of magnets (110) are of the same size and are uniformly arranged along the circumference of the annular rotor (100) at the inner ring of the annular rotor (100).

6. The rotor assembly according to any one of claims 1-3, characterized in that, The plurality of magnets (110) are fixed to the inner ring of the annular rotor (100) by adhesive bonding.

7. The rotor assembly according to claim 2 or 3, characterized in that, The magnetorheological fluid includes a magnetic material, which includes one or more of the following: iron, cobalt or nickel and their alloys.

8. An electric motor, characterized in that, The motor is provided with a rotor assembly according to any one of claims 1-7, the motor including a stator, the stator being coaxially arranged with an annular rotor (100) of the rotor assembly and the annular rotor (100) being located outside the stator.

9. An electric vehicle, characterized in that, The electric vehicle is equipped with a motor according to claim 8, the motor is fixed to the frame via an axle, and the electric vehicle includes spokes, one end of which is fixed to a wheel rim and the other end is fixed to the motor.

10. The electric vehicle according to claim 9, characterized in that, The electric vehicle is either an electric motorcycle or an electric bicycle.

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