A rotor, motor and air conditioner

Abstract

This application provides a rotor, a motor, and an air conditioner. The rotor includes a shaft, a rotor core, and multiple magnets. The rotor core includes multiple core units arranged circumferentially along the shaft, with a receiving space defined between each pair of adjacent core units. The magnets include equal-width portions and reduced-width portions arranged radially and interconnected. The equal-width portions are located within corresponding receiving spaces, while the reduced-width portions are located radially inside the equal-width portions and outside the receiving spaces. Along the radial direction of the rotor and towards the shaft, the circumferential dimension of the reduced-width portions decreases. The magnets achieve circumferential positioning with the core units through the equal-width portions, but the reduced-width portions and core units do not form a circumferential positioning fit. The rotor provided in this application balances the manufacturability of the magnets and the efficiency of the motor.

Description

Technical Field

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

[0002] Compared with traditional motors, permanent magnet synchronous motors have advantages such as simple structure, high efficiency and good performance, so they are widely used in various fields.

[0003] In a permanent magnet synchronous motor, the magnetic field generated by the stator windings interacts with the magnetic field generated by the rotor to provide driving torque for the rotor. During mass production of these motors, product yield has become a key concern in the industry. Utility Model Content

[0004] This application provides a rotor, a motor, and an air conditioner, which takes into account both the manufacturability of the magnets and the efficiency of the motor, thus helping to improve product yield.

[0005] This application provides a rotor, including: Shaft; The rotor core includes multiple core units, which are arranged circumferentially along the shaft, and a receiving space is defined between each two adjacent core units. Multiple magnets, each magnet comprising equal-width portions and reduced-width portions arranged radially and interconnected, the equal-width portions being disposed within corresponding receiving spaces, the reduced-width portions being located radially inside the equal-width portions and outside the receiving spaces, along the radial direction of the rotor and toward the rotating shaft, the reduced-width portions having a smaller circumferential dimension, the magnets achieving circumferential positioning engagement with the core unit through the equal-width portions, and the reduced-width portions and the core unit not forming a positioning engagement in the circumferential direction.

[0006] In some embodiments, the core unit includes two first side surfaces arranged circumferentially opposite each other, projected onto a plane perpendicular to the axis of rotation. The radial inner edge of the projection of the first side surface of each core unit is located on a first circle, and the projections of the equal-width portion and the reduced portion are located on opposite sides of the first circle in the radial direction.

[0007] In some embodiments, the core unit includes two first side surfaces arranged circumferentially opposite each other, projected orthographically onto a plane perpendicular to the axis of rotation. The projections of the first side surfaces are straight lines in a radial direction close to the axis of rotation, and the projections of the two first side surfaces extend toward each other and extend to the first circle.

[0008] In some embodiments, the radially inner end of the reduced portion abuts against the outer peripheral surface of the rotating shaft to limit the radially inner end of the magnet by means of the rotating shaft; or, the rotor includes an annular limiting member, the annular limiting member and the rotor core are separate structures, the annular limiting member includes an annular portion and a plurality of protrusions, the annular portion is disposed on the outer periphery of the rotating shaft and located on the radially inner side of the magnet, the plurality of protrusions are disposed on the outer periphery of the annular portion, and the protrusions are used to abut against the corresponding magnets.

[0009] In some implementations, the circumferential distance between two adjacent reduced portions is 0.3 mm to 1 mm.

[0010] In some implementations, the equal-width portion includes two second side surfaces arranged circumferentially opposite each other, the distance between the second side surface and the adjacent core unit not exceeding 0.1 mm.

[0011] In some embodiments, the ratio of the diameter of the circumscribed circle of the reduced portion to the outer diameter of the rotor is 0.3-0.5; and / or, the ratio of the circumferential dimension of the equal-width portion to the outer diameter of the rotor is 0.08-0.2.

[0012] In some embodiments, the reduced portion includes two third side surfaces disposed opposite each other in the circumferential direction, the included angle between the two third side surfaces being 36°-60°.

[0013] In some embodiments, the rotor includes an injection molded part, the rotor core and the magnet are connected through the injection molded part, and the reduced portion includes two third side surfaces arranged circumferentially opposite each other, the third side surfaces having grooves for filling the injection molded part with injection plastic.

[0014] This application provides an electric motor, including a stator and a rotor as described in any embodiment of this application, wherein the stator is disposed around the outer periphery of the rotor.

[0015] This application also provides an air conditioner, including the motor described in any embodiment of this application.

[0016] Compared to embodiments where both the equal-width portion and the reduced-width portion are located in the accommodating space, the rotor provided in this application reduces the machining accuracy requirements for the reduced-width portion because the reduced-width portion and the core unit do not form a positioning fit in the circumferential direction. Only the machining accuracy of the equal-width portion needs to be ensured. This helps improve the manufacturability of the magnets, thereby improving the manufacturability of the rotor, which helps reduce manufacturing costs and manufacturing efficiency. During rotor assembly, there is no need to focus on the assembly accuracy of the reduced-width portion and the core unit, which helps improve product yield.

[0017] By setting a reduction section, it is helpful to increase the radial dimension of the magnet along the rotor, thereby helping to increase the overall volume of the magnet. A portion of the magnetic field lines of the reduction section will enter the rotor core through the air, and then pass through the air gap between the stator and the rotor to form an effective main magnetic flux. Compared with the comparative example where the magnet only has a section of equal width, the rotor of the embodiment of this application helps to increase the air gap magnetic flux density, which helps to improve the motor efficiency.

[0018] In other words, the rotor in this application embodiment takes into account both the manufacturability of the magnets and the efficiency of the motor. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the rotor structure provided in an embodiment of this application; Figure 2 for Figure 1 An enlarged schematic diagram of part A in the structure shown; Figure 3 for Figure 1 A schematic diagram of the magnet structure shown; Figure 4 for Figure 1 A schematic diagram of the structure of some core units before injection molding is shown. Figure 5 This is a schematic diagram of the rotor provided in the second embodiment of this application.

[0020] Explanation of reference numerals in the attached figures 10. Shaft; 20. Rotor core; 21. Core unit; 21a. Radial outer end face of core unit; 211. First side face; 212. Protrusion; 30. Magnet; 31. Equal width portion; 31a. Radial outer end of equal width portion; 311. Second side face; 32. Reduction portion; 32a. Radial inner end of reduction portion; 321. Third side face; 321a. Groove; 40. Injection molded part; 50. Annular limiting part; 51. Ring portion; 52. Protrusion; S1. First arc segment; S2. Second arc segment; S3. Third arc segment; G1. First circle; G2. Outer circle of reduction portion; G3. Outer circle of rotor core.

[0021] It should be noted that the terms "first" and "second" mentioned above are only used to distinguish between different options and do not represent the degree of superiority or inferiority of the options or their priority in the implementation process. Detailed Implementation

[0022] The embodiments of this application will be described in further detail below with reference to the accompanying drawings and examples. The following examples are used to illustrate this application, but should not be used to limit the scope of this application.

[0023] In the description of the embodiments of this application, it should be noted that the terms "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing the embodiments of this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0024] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" 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. Those skilled in the art can understand the specific meaning of the above terms in the embodiments of this application based on the specific circumstances.

[0025] In the embodiments of this application, unless otherwise expressly specified and limited, "above" or "below" the second feature can mean that the first feature and the second feature are in direct contact, or that the first feature and the second feature are in indirect contact through an intermediate medium. Furthermore, "above," "on top of," and "over" the second feature can mean that the first feature is directly above or diagonally above the second feature, or simply that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature can mean that the first feature is directly below or diagonally below the second feature, or simply that the first feature is at a lower horizontal level than the second feature.

[0026] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., refer to specific features, structures, materials, or characteristics described in connection with that embodiment or example, which are included in at least one embodiment or example of the embodiments of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples. Moreover, without contradiction, those skilled in the art can combine and integrate the different embodiments or examples described in this specification, as well as the features of different embodiments or examples.

[0027] This application provides a rotor; please refer to [the relevant documentation]. Figure 1 The rotor includes a shaft 10, a rotor core 20, and multiple magnets 30.

[0028] The rotating shaft 10 serves as the rotation center of the rotor and is responsible for transmitting torque.

[0029] The rotor core 20 includes multiple core units 21, which are arranged circumferentially along the shaft 10, and each pair of adjacent core units 21 defines a receiving space.

[0030] It should be noted that the "spaced arrangement" refers to the circumferential gap between two adjacent core units 21, and that the two adjacent core units 21 do not contact each other. In some embodiments, the magnet 30 includes a uniform width portion 31 and a reduced width portion 32 arranged radially and connected to each other. The uniform width portion 31 is disposed within a corresponding receiving space, and the reduced width portion 32 is located radially inside the uniform width portion 31 and outside the receiving space. Along the radial direction of the rotor and towards the rotating shaft 10, the circumferential dimension of the reduced width portion 32 decreases. The magnet achieves circumferential positioning and engagement with the core unit through the uniform width portion, but the reduced width portion and the core unit do not constitute a positioning engagement in the circumferential direction.

[0031] For example, the core unit 21 includes two first side surfaces 211 disposed opposite each other in the circumferential direction.

[0032] The equal-width portion 31 includes two second side surfaces 311 arranged opposite each other in the circumferential direction.

[0033] The reduced portion 32 includes two third side surfaces 321 arranged opposite each other in the circumferential direction.

[0034] It should be noted that the magnet 30 achieves circumferential positioning and engagement with the core unit 21 through the equal-width portion 31. This means that during assembly, the first side surface 211 and its adjacent second side surface 311 form a positioning and engagement surface. Since the reduced portion 32 is located outside the accommodating space, the third side surface 321 does not need to be circumferentially positioned and engaged with the first side surface 211. In other words, during assembly, the magnet 30 achieves overall positioning based on the positioning and engagement between the equal-width portion 31 and the core unit 21.

[0035] In this embodiment, a receiving space is used to place a constant-width portion 31, and the receiving space and the constant-width portion 31 have a one-to-one mapping relationship.

[0036] It should be noted that the equal width portion 31 refers to the circumferential dimension remaining unchanged along the radial direction, that is, the two second side surfaces 311 are parallel to each other.

[0037] For example, the reduction portion 32 includes two third side surfaces 321 disposed circumferentially opposite each other, extending radially and close to the axis of rotation 10, with the two third side surfaces 321 extending toward each other. That is, the third side surface 321 is inclined from the radially inner end of the second side surface 311 toward the other third side surface 321.

[0038] In some related technologies, both the equal-width section and the reduced-width section of the magnet are located within the receiving space. The sides of both the equal-width section and the reduced-width section form positioning mating surfaces with the iron core. Therefore, the machining accuracy requirements for both the equal-width section and the reduced-width section are relatively high. The cross-sectional shape of the equal-width section is roughly rectangular, which is relatively easy to machine. However, the machining of the sides of the reduced-width section is more difficult, making it hard to guarantee machining accuracy. This leads to high manufacturing costs and also results in low assembly accuracy between the magnet and the iron core unit, leading to a high product defect rate.

[0039] The rotor provided in this application embodiment does not have a positioning fit between the reduced portion 32 and the core unit 21 in the circumferential direction, which reduces the requirements for the machining accuracy of the reduced portion 32. Only the machining accuracy of the equal-width portion 31 needs to be ensured. This helps to improve the manufacturability of the magnet 30, thereby improving the manufacturability of the rotor, which helps to reduce manufacturing costs and manufacturing efficiency. During rotor assembly, there is no need to pay attention to the assembly accuracy of the reduced portion 32 and the core unit 21, which helps to improve product yield.

[0040] By providing the reduction section 32, it is helpful to increase the radial dimension of the magnet 30 along the rotor, thereby helping to increase the overall volume of the magnet 30. A portion of the magnetic field lines of the reduction section 32 will enter the rotor core 20 through the air, and then pass through the air gap between the stator and the rotor to form an effective main magnetic flux. Compared with the comparative example where the magnet only has a uniform width section, the rotor of the embodiment of this application helps to increase the air gap magnetic flux density, which helps to improve the motor efficiency.

[0041] In other words, the rotor of this application embodiment takes into account both the manufacturability of the magnet 30 and the efficiency of the motor.

[0042] In some embodiments, the dimensional accuracy of the equal-width portion 31 in the circumferential direction does not exceed 0.1 mm. That is, the maximum error between the actual size of the equal-width portion 31 in the circumferential direction and the design value (i.e., the nominal size) is within ±0.1 mm, that is, the actual size of the equal-width portion 31 is within the nominal size ±0.1 mm.

[0043] In some embodiments, the dimensional accuracy of the reduced portion 32 in the circumferential direction does not exceed 0.25 mm. That is, the maximum error between the actual size of the reduced portion 32 in the circumferential direction and the design value (i.e., the nominal size) is within ±0.25 mm, that is, the actual size of the equal-width portion 31 is within the nominal size ±0.25 mm.

[0044] Understandably, since the machining accuracy requirements for the reduced portion 32 are not high, the third side surface 321 can be either a plane or a curved surface.

[0045] For example, the reduced portion 32 and the equal-width portion 31 are integrally formed. The integral forming helps to improve the structural strength of the magnet 30, and also helps to eliminate the need for assembly between the reduced portion 32 and the equal-width portion 31.

[0046] It is understandable that the connection method between the rotor core 20, the magnet 30 and the shaft 10 is not limited.

[0047] For example, in some embodiments, the rotor core 20, magnet 30 and shaft 10 are connected by injection molding.

[0048] In this embodiment, the rotor includes an injection molded part 40, and the rotor core 20, magnet 30 and rotating shaft 10 are connected through the injection molded part 40.

[0049] For example, the rotor core 20, magnet 30 and shaft 10 can be placed into a mold, and then the injection molding material of the injection molded part 40 can be injected into the mold. The injection molding material of the injection molded part 40 covers the outside of the rotor core 20, and also fills the gap area between the magnet 30 and the core unit 21, the gap area between the core unit 21 and the shaft 10, and the gap area between two adjacent reduced parts 32. After cooling and molding, the rotor core 20, magnet 30 and shaft 10 are all connected by the injection molded part 40, and the injection molded part 40 serves as the appearance part of the rotor.

[0050] In some embodiments, the third side surface 321 is formed with a groove 321a for filling the injection molding material of the injection molded part 40. This helps to increase the contact area between the reduced portion 32 and the injection molding material of the injection molded part 40, and helps to increase the connection stability between the reduced portion 32 and the injection molding material.

[0051] In some embodiments, in orthographic projection onto a plane perpendicular to the axis of rotation 10, the radial inner edge of the projection of the first side surface 211 of each core unit 21 is located on the first circle G1, and the projections of the equal width portion 31 and the reduced portion 32 are located on opposite sides of the first circle G1 in the radial direction.

[0052] It should be noted that the projections of the equal-width portion 31 and the reduced portion 32 are located on opposite sides of the first circle G1 in the radial direction. This means that the boundary between the projections of the equal-width portion 31 and the reduced portion 32 is approximately located on the first circle G1. The boundary between the projections of the equal-width portion 31 and the reduced portion 32 is either the circumcircle of the projection of the reduced portion 32 or the incircle of the projection of the equal-width portion 31. The boundary being approximately located on the first circle G1 means that the radial distance between the boundary and the first circle G1 can be 0 or close to 0, allowing for certain machining and assembly errors. For example, the radial distance t3 between the circumcircle G2 of the projection of the reduced portion 32 and the first circle G1 can be 0-3 mm (millimeters). That is, 0 ≤ t3 ≤ 3 mm. For example, t3 can be 0 mm, 0.5 mm, 1 mm, 2 mm, 2.5 mm, 3 mm, etc., meaning that within this range, the boundary can be determined to be approximately located on the first circle G1.

[0053] It is understandable that when t3 is greater than 0, the circumcircle G2 of the projection of the reduced portion 32 may be located radially inside the first circle G1, or the circumcircle G2 of the projection of the reduced portion 32 may be located radially outside the first circle G1.

[0054] In this embodiment, the reduced portion 32 is located radially inside the first circle G1, so that the reduced portion 32 does not need to be assembled with the core unit 21.

[0055] In some embodiments, when projected onto a plane perpendicular to the rotation axis 10, the projection of the first side surface 211 is a straight line, extending radially and close to the rotation axis 10, and the projections of the two first side surfaces 211 extend towards each other. This makes the first side surface 211 parallel to the second side surface 311, which helps to ensure the assembly accuracy of the first side surface 211 and the second side surface 311.

[0056] In some embodiments, the distance t2 between the second side 311 and the adjacent core unit 21 does not exceed 0.1 mm. That is, the distance between the second side 311 and its adjacent first side 211 does not exceed 0.1 mm, so as to ensure the assembly accuracy of the first side 211 and the second side 311.

[0057] In some embodiments, such as Figure 1 As shown, the radial inner end 32a of the reduced portion 32 abuts against the outer peripheral surface of the rotating shaft 10, thereby limiting the radial inner end of the magnet 30 by the rotating shaft 10. In this way, the radial dimension of the reduced portion 32 is made as long as possible, which helps to increase the volume of the reduced portion 32, thereby helping to increase the magnetic field lines of the reduced portion 32 entering the rotor core 20, and helping to increase the air gap magnetic flux density.

[0058] In some other embodiments, such as Figure 5 As shown, the rotor includes an annular limiting member 50, which is a separate structure from the rotor core 20. The annular limiting member 50 includes an annular portion 51 and multiple protrusions 52. The annular portion 51 is located on the outer periphery of the rotating shaft 20 and radially inner to the magnet 30. The multiple protrusions 52 are located on the outer periphery of the annular portion 51 and are used to abut against the corresponding magnet 30. In this way, the multiple protrusions 52 facilitate the limiting of the radially inner ends 32a of the multiple reduced portions 32, and the limiting by the multiple protrusions 52 also helps to reduce the machining requirements of the annular portion 51.

[0059] In this embodiment, the injection molding material of the injection molded part 40 fills the area between the annular limiting member 50 and the magnet 30, the area between the annular limiting member 50 and the iron core unit 21, and the area between the annular limiting member 50 and the rotating shaft 10.

[0060] For example, the ring portion 51 and the plurality of protrusions 52 are an integral structure.

[0061] For example, the circumferential distance t1 between two adjacent reduced portions 32 is 0.3mm-1mm. This helps to ensure the circumferential dimension of the reduced portion 32, thereby helping to increase the volume of the reduced portion 32.

[0062] In some embodiments, the ratio of the diameter D2 of the circumcircle G2 of the reduced portion to the outer diameter D1 of the rotor is 0.3-0.5. That is, 0.3≤D2 / D1≤0.5, for example, D2 / D1 can be 0.3, 0.4, 0.5, etc.

[0063] It should be noted that the outer diameter of the rotor refers to the diameter of the circumcircle G3 of the rotor core 20. The circumcircle G3 of the rotor core is a circle that is tangent to the radial outer edge of the projection of the core unit 21, centered on the projection O1 of the axis of the rotating shaft 10, when projected onto a plane perpendicular to the rotating shaft 10. By controlling D2 / D1 within this range, the radial dimension of the reduced portion 32 is within a reasonable range, and the radial dimension of the equal-width portion 31 is within a reasonable range. This helps to ensure that the volume of the magnet 30 located within the accommodating space, as well as the overall volume of the magnet 30, is within a reasonable range.

[0064] In some embodiments, the ratio of the circumferential dimension w of the equal-width portion 31 to the outer diameter D1 of the rotor is 0.08-0.2. That is, 0.08 ≤ w / D1 ≤ 0.2, for example, w / D1 can be 0.08, 0.1, 0.2, etc. By controlling w / D1 within this range, it helps to make the circumferential dimension of the equal-width portion 31 reasonable, and helps to make the overall volume of the magnet 30 more suitable.

[0065] In some embodiments, the included angle α between the two third sides 321 is 36°-60°. That is, 36°≤α≤60°, for example, α can be 36°, 40°, 45°, 50°, 52°, 55°, 60°, etc.

[0066] It should be noted that the included angle between the two third sides 321 refers to the acute angle formed when the two third sides 321 extend radially toward each other until they intersect.

[0067] By controlling the included angle α between the two third side surfaces 321 within a reasonable range, it helps to control the degree of reduction in the circumferential dimension of the reduced portion 32, so that the circumferential dimension of the reduced portion 32 is within a suitable range.

[0068] In some embodiments, a protrusion 212 is formed at the radially outer end of the first side surface 211, and the equal-width portion 31 is located radially inside the protrusion 212. The protrusion 212 is used to limit the radially outer end 31a of the equal-width portion 31 in the radial direction, so that the equal-width portion 31 is located more stably within the receiving space.

[0069] For example, the protrusions 212 of two adjacent core units 21 are spaced circumferentially apart. In this way, the magnet 30 is limited while the two adjacent core units 21 do not come into contact, which helps to reduce magnetic leakage.

[0070] For example, the circumferential distance c between the protrusions 212 of two adjacent core units 21111 is 1.5mm-3.5mm. That is, 1.5mm≤c1≤3.5mm. For example, c1 can be 1.5mm, 1.8mm, 2mm, 2.5mm, 3.5mm, etc. By controlling the distance c between the protrusions 212 of two adjacent core units 21 within a reasonable range, on the one hand, the protrusions 212 have a certain size in the circumferential direction to limit the radial outer end of the magnet 30, and on the other hand, it helps to avoid contact between the two protrusions 212 and the generation of magnetic leakage.

[0071] In some embodiments, the radial outer end face 21a of the core unit 21 includes a first arc-shaped segment S1, a second arc-shaped segment S2, and a third arc-shaped segment S3 connected sequentially along the circumference. The curvatures of the first arc-shaped segment S1 and the second arc-shaped segment S2 are different, and the curvatures of the second arc-shaped segment S2 and the third arc-shaped segment S3 are also different. By designing the radial outer end face 21a of the core unit 21 as an arc-shaped segment, it helps to optimize the air gap magnetic field distribution between the stator and the rotor, making the air gap magnetic field closer to the ideal sine wave, which helps to reduce the harmonic content of the motor and reduce the torque pulsation of the motor.

[0072] Moreover, the curvatures of the first arc segment S1 and the second arc segment S2 are different, and the curvatures of the second arc segment S2 and the third arc segment S3 are different. That is, the first arc segment S1, the second arc segment S2 and the third arc segment S3 do not belong to the same circumference of the arc, which helps to further optimize the air gap magnetic field distribution between the stator and the motor, thereby further reducing the harmonic content of the motor.

[0073] For example, the center of the second arc segment S2 is located on the rotation axis of the rotating shaft 10. That is, the second arc segment S2 is concentrically arranged with the rotating shaft 10.

[0074] In some embodiments, the first arc segment S1 and the third arc segment S3 are symmetrically arranged about the second arc segment S2.

[0075] It should be noted that the plane of symmetry of the second arc segment S2 passes through the midpoint of the arc length of the second arc segment S2 and the axis of rotation.

[0076] For example, the ratio of the central angle θ corresponding to the second arc segment S2 to the angle β between the two adjacent magnets 30 is 0.2-0.6. That is, 0.2≤θ / β≤0.6. For example, θ / β can be 0.2, 0.3, 0.4, 0.6, etc.

[0077] It should be noted that the magnet 30 has a plane of symmetry. This plane of symmetry passes through the axis of rotation and serves to divide the magnet 30 into two identical parts. The included angle β between two adjacent magnets 30 refers to the included angle between the planes of symmetry of two adjacent magnets 30. Please refer to [link / reference]. Figure 1 The projection of the plane perpendicular to the rotation axis 10 is a straight line L1. The angle between the symmetrical planes of two adjacent magnets 30 is the angle between two adjacent straight lines L1.

[0078] In this embodiment, given the limited outer diameter of the rotor, by limiting the ratio of the central angle θ corresponding to the second arc segment S2 to the included angle β between the two adjacent magnets 30, the ratio of the arc length of the second arc segment S2 to the circumferential distance between the two adjacent magnets 30 is kept within a reasonable range. This helps to further optimize the magnetic circuit structure and reduce the harmonic content.

[0079] For example, the magnet 30 is magnetized tangentially, that is, one of the two opposing walls of the magnet 30 along the axial direction forms the N pole and the other forms the S pole. Moreover, when multiple magnets 30 are placed in the corresponding receiving space, the N poles of two adjacent magnets 30 are opposite each other circumferentially, and the S poles of two adjacent magnets 30 are opposite each other circumferentially.

[0080] This application also provides an electric motor, including a stator and a rotor according to any embodiment of this application, with the stator surrounding the outer periphery of the rotor. The electric motor of this application embodiment helps to simultaneously achieve manufacturability and motor efficiency.

[0081] This application also provides an air conditioner, including a motor according to any embodiment of this application.

[0082] The various embodiments / implementations provided in this application can be combined with each other without creating contradictions.

[0083] The above description is merely a preferred embodiment of this application and is not intended to limit the application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.

Claims

1. A rotor, characterized in that, include: Shaft; The rotor core includes multiple core units, which are arranged circumferentially along the shaft, and a receiving space is defined between each two adjacent core units. Multiple magnets, each magnet comprising equal-width portions and reduced-width portions arranged radially and interconnected, the equal-width portions being disposed within corresponding receiving spaces, the reduced-width portions being located radially inside the equal-width portions and outside the receiving spaces, along the radial direction of the rotor and toward the rotating shaft, the reduced-width portions having a smaller circumferential dimension, the magnets achieving circumferential positioning engagement with the core unit through the equal-width portions, and the reduced-width portions and the core unit not forming a positioning engagement in the circumferential direction.

2. The rotor according to claim 1, characterized in that, The core unit includes two first side surfaces arranged opposite each other in the circumferential direction. When projected onto a plane perpendicular to the axis of rotation, the radial inner edge of the projection of the first side surface of each core unit is located on a first circle. The projection of the equal-width portion and the projection of the reduced portion are located on opposite sides of the first circle in the radial direction.

3. The rotor according to claim 1, characterized in that, The core unit includes two first side surfaces arranged circumferentially opposite each other. When projected onto a plane perpendicular to the axis of rotation, the projection of the first side surface is a straight line along the radial direction and close to the axis of rotation. The projections of the two first side surfaces extend toward each other.

4. The rotor according to claim 1, characterized in that, The radial inner end of the reduced portion abuts against the outer circumferential surface of the rotating shaft to limit the radial inner end of the magnet by the rotating shaft; or, the rotor includes an annular limiting member, the annular limiting member and the rotor core are separate structures, the annular limiting member includes an annular portion and a plurality of protrusions, the annular portion is located on the outer circumference of the rotating shaft and on the radial inner side of the magnet, the plurality of protrusions are located on the outer circumference of the annular portion, and the protrusions are used to abut against the corresponding magnet.

5. The rotor according to any one of claims 1 to 4, characterized in that, The circumferential distance between two adjacent reduced portions is 0.3mm-1mm.

6. The rotor according to any one of claims 1 to 4, characterized in that, The equal-width portion includes two second side surfaces arranged opposite each other in the circumferential direction, and the distance between the second side surface and the adjacent core unit does not exceed 0.1 mm.

7. The rotor according to any one of claims 1 to 4, characterized in that, The ratio of the diameter of the circumscribed circle of the reduced portion to the outer diameter of the rotor is 0.3-0.5; and / or the ratio of the circumferential dimension of the equal-width portion to the outer diameter of the rotor is 0.08-0.

2.

8. The rotor according to any one of claims 1 to 4, characterized in that, The reduced portion includes two third side surfaces arranged opposite each other in the circumferential direction, with an included angle of 36°-60° between the two third side surfaces.

9. The rotor according to any one of claims 1 to 4, characterized in that, The rotor includes an injection molded part, the rotor core and the magnet are connected through the injection molded part, and the shrinking part includes two third side surfaces arranged opposite each other in the circumferential direction. The third side surfaces are formed with grooves, and the grooves are used to fill the injection plastic of the injection molded part.

10. An electric motor, characterized in that, It includes a stator and a rotor as described in any one of claims 1 to 9, the stator being disposed around the outer periphery of the rotor.

11. An air conditioner, characterized in that, Including the motor as described in claim 10.

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