Rotor core, rotor assembly and permanent magnet motor

Abstract

This application relates to the field of motor technology, and in particular to a rotor core, rotor assembly, and permanent magnet motor. The rotor core includes an inner core and an outer core arranged coaxially. The outer core is sleeved on the outer periphery of the inner core, and a receiving groove for accommodating permanent magnets is formed between the outer core and the inner core. This rotor core can effectively prevent the glue on the surface of the permanent magnets from being scraped off during the trial production process, ensuring the bonding force between the core laminations, and thus ensuring the stable and reliable operation of the permanent magnet motor.

Description

Technical Field

[0001] This application relates to the field of motor technology, and in particular to a rotor core, rotor assembly and permanent magnet motor. Background Technology

[0002] In the application of high-speed permanent magnet motors, rotor structures include surface-mounted and embedded structures. Embedded rotors can increase the torque density and magnetic flux density of the motor within a fixed rotor volume. Embedded rotors also avoid the problem of permanent magnets easily detaching at high speeds, which is common with surface-mounted rotors.

[0003] The embedded rotor structure of a permanent magnet motor typically involves cutting corresponding permanent magnet slots into the rotor core laminations, stacking the rotor core laminations axially to form the rotor core, applying adhesive to the surface of the permanent magnets, placing them into the permanent magnet slots, and then pushing them into the slots using appropriate tooling. During rotor prototyping, the adhesive on the surface of the permanent magnets is easily scraped off by the rotor core when pushed into the slots, resulting in insufficient adhesion between the core laminations. This poses a risk of loosening during high-speed operation, affecting the stability and reliability of the permanent magnet motor. Summary of the Invention

[0004] The purpose of this application is to provide a rotor core, rotor assembly and permanent magnet motor. The rotor core can effectively prevent the glue on the surface of the permanent magnet from being scraped off during the trial production process, ensure the bonding force between the core laminations, and thus ensure the stable and reliable operation of the permanent magnet motor.

[0005] Therefore, in a first aspect, embodiments of this application provide a rotor core, including an inner core and an outer core coaxially arranged, with the outer core sleeved on the outer periphery of the inner core, and a receiving groove for accommodating a permanent magnet formed between the outer core and the inner core.

[0006] In one possible implementation, the outer peripheral surface of the inner core is provided with a first fixing surface for fixing the permanent magnet, and the inner surface of the outer core is provided with a second fixing surface for limiting the permanent magnet, with a receiving groove formed between the first fixing surface and the second fixing surface.

[0007] In one possible implementation, a first positioning protrusion is provided on the outer peripheral surface of the inner core along the axial direction of the inner core. The first positioning protrusion is located at the edge of the first fixed surface and is used to position the permanent magnet along the axial direction.

[0008] In one possible implementation, the inner surface of the outer core is provided with a second positioning protrusion along the axial direction. The second positioning protrusion is used to abut against the first positioning protrusion so that the inner core and the outer core are positioned along the axial direction.

[0009] In one possible implementation, the side of the first positioning protrusion facing the second positioning protrusion has a first positioning surface, and the side of the second positioning protrusion facing the first positioning protrusion has a second positioning surface. The first positioning surface is used to abut against the second positioning surface so that the inner core and the outer core are positioned circumferentially.

[0010] In one possible implementation, the second positioning protrusion has a weight-reducing groove on at least one side of the second positioning surface about the axial direction.

[0011] In one possible implementation, the radial thickness of the inner core is d1 ≥ 2 mm, and the radial thickness of the outer core is d2 ≥ 2 mm.

[0012] In one possible implementation, multiple receiving slots are provided, and the multiple receiving slots are evenly distributed along the circumference of the rotor core.

[0013] Secondly, embodiments of this application provide a rotor assembly, including: the aforementioned rotor core; and a permanent magnet disposed within a receiving slot of the rotor core.

[0014] In one possible implementation, the permanent magnet in the receiving slot includes multiple permanent magnet units, which are arranged sequentially along the axial direction of the rotor core.

[0015] In one possible implementation, the rotor assembly further includes two rotor end plates and pins, with the two rotor end plates respectively disposed at both ends of the rotor core along the axial direction, and the rotor end plates connected to the rotor core by pins.

[0016] Thirdly, embodiments of this application provide a permanent magnet motor, including the rotor assembly described above.

[0017] According to the rotor core, rotor assembly, and permanent magnet motor provided in the embodiments of this application, the rotor core is divided into an inner core and an outer core that are coaxial. The permanent magnet can be fixed on the outer surface of the inner core first, and then the inner core together with the permanent magnet can be assembled into the outer core. This can effectively avoid the glue on the surface of the permanent magnet being scraped off during the trial production process, ensure the bonding force between the core laminations, and thus ensure the stable and reliable operation of the permanent magnet motor. Attached Figure Description

[0018] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0020] One or more embodiments are illustrated by way of example with reference numerals in the accompanying drawings. These illustrations do not constitute a limitation on the embodiments. Elements with the same reference numerals in the drawings are denoted as similar elements. Unless otherwise stated, the figures in the drawings are not to be limited by scale.

[0021] Figure 1 This diagram illustrates the structure of an exploded rotor assembly according to an embodiment of this application.

[0022] Figure 2 Show Figure 1 A partially enlarged structural diagram of point A of the rotor assembly shown;

[0023] Figure 3 Show Figure 1 A partially enlarged structural diagram of point B of the rotor assembly shown;

[0024] Figure 4 This illustration shows a three-dimensional structural diagram of a rotor assembly provided in an embodiment of this application;

[0025] Figure 5 This diagram shows a cross-sectional structure of a rotor core, permanent magnet, and pin provided in an embodiment of this application.

[0026] Explanation of reference numerals in the attached figures:

[0027] 1. Inner core; 11. First fixing surface; 12. First positioning protrusion; 121. First positioning surface;

[0028] 2. Outer iron core; 21. First fixing surface; 22. Second positioning protrusion; 221. Second positioning surface; 222. Weight reduction groove;

[0029] 3. Permanent magnet; 31. Permanent magnet unit;

[0030] 4. Rotor end plate; 5. Pin. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0032] The following disclosure provides many different embodiments or examples for implementing different structures of the embodiments of this application. To simplify the disclosure of the embodiments of this application, components and arrangements of specific examples are described below. Of course, these are merely examples and are not intended to limit the embodiments of this application. Furthermore, reference numerals and / or letters may be repeated in different examples of the embodiments of this application. Such repetition is for simplification and clarity and does not in itself indicate a relationship between the various embodiments and / or arrangements discussed.

[0033] For ease of description, spatial relative terms may be used in the text to describe the relative position or movement of one element or feature relative to another element or feature, as shown in the figure. These relative terms include, for example, "inside," "outside," "middle," "outer," "below," "below," "above," "front," "back," etc. Such spatial relative terms are intended to include different orientations of the device in use or operation, other than those depicted in the figure. For example, if the device in the figure undergoes a positional flip, orientation change, or change of motion, these directional indications will change accordingly. For instance, an element described as "below other elements or features" or "below other elements or features" will subsequently be oriented "above other elements or features" or "above other elements or features." Therefore, the example term "below" can include both upper and lower orientations. The device may be otherwise oriented (rotated 90 degrees or in other directions), and the spatial relative descriptors used in the text will be interpreted accordingly.

[0034] To address the problems in the prior art, this application provides a rotor core that can effectively prevent the glue on the surface of the permanent magnet from being scraped off during the trial production process, ensuring the bonding force between the core laminations, and thus guaranteeing the stable and reliable operation of the permanent magnet motor.

[0035] Figure 1 This diagram illustrates the structure of an exploded rotor assembly according to an embodiment of this application. Figure 2 Show Figure 1 A partially enlarged structural diagram of point A of the rotor assembly shown; Figure 3 Show Figure 1 A partially enlarged structural diagram of point B of the rotor assembly shown; Figure 4 This illustration shows a three-dimensional structural diagram of a rotor assembly provided in an embodiment of this application; Figure 5 This diagram shows a cross-sectional structure of a rotor core, permanent magnet, and pin provided in an embodiment of this application.

[0036] like Figures 1 to 5 As shown in the embodiment of this application, a rotor core includes an inner core 1 and an outer core 2 arranged coaxially. The outer core 2 is sleeved on the outer periphery of the inner core 1, and a receiving groove for accommodating a permanent magnet 3 is formed between the outer core 2 and the inner core 1.

[0037] In this application, by dividing the rotor core into a coaxial inner core 1 and an outer core 2, the permanent magnet 3 can be fixed on the outer surface of the inner core 1 first, and then the inner core 1 together with the permanent magnet 3 can be assembled into the outer core 2. This can effectively prevent the glue on the surface of the permanent magnet 3 from being scraped off during the trial production process, ensure the bonding force between the core laminations, and thus ensure the stable and reliable operation of the permanent magnet motor.

[0038] In related technologies, when the permanent magnet 3 is applied with adhesive and then pushed into the permanent magnet slot of the rotor core using appropriate tooling, it is inconvenient to install the permanent magnet 3. Furthermore, pushing the permanent magnet 3 into the slot using tooling can easily damage the permanent magnet 3, making it difficult to remove the damaged magnet from the slot. However, in this embodiment, the rotor core is divided into an inner core 1 and an outer core 2, and the permanent magnet... After the permanent magnet 3 is coated with adhesive, it is first fixed to the outer surface of the inner core 1. After the permanent magnet 3 is fixed to the inner core 1, the inner core 1 and the permanent magnet 3 are then installed into the outer core 2. This facilitates the installation of the permanent magnet 3 and eliminates the need for tooling to press the permanent magnet 3 into place, reducing the possibility of damage to the permanent magnet 3 during assembly. If the permanent magnet 3 is damaged later, the inner core 1 and the permanent magnet 3 can be pulled out from the outer core 2 together, making it easy to remove the damaged permanent magnet 3.

[0039] In related technologies, for rotor cores with long axial lengths, multiple permanent magnets 3 need to be arranged along the axial direction. This requires pushing the multiple permanent magnets 3 one by one into the permanent magnet slots of the rotor core using tooling. In this case, the axial end faces of the internal permanent magnets 3 may not make proper contact. However, in the embodiment of this application, for rotor assemblies that require multiple permanent magnets 3 to be arranged along the axial direction, a split structure of inner core 1 and outer core 2 is adopted. This allows direct observation of the axial contact between the permanent magnets 3 when the multiple permanent magnets 3 are fixed on the outer surface of the inner core 1, thereby avoiding the situation where the axial end faces of the permanent magnets 3 do not make proper contact.

[0040] In related technologies, when the permanent magnet 3 is pushed into the permanent magnet slot of the embedded integral rotor core after being coated with adhesive, most of the adhesive on the surface of the permanent magnet 3 is scraped off by the rotor core. Over time, this can easily cause the permanent magnet 3 to detach. Furthermore, the adhesive that overflows onto the surface of the permanent magnet 3 and near the permanent magnet slot of the rotor core cannot be cleaned, weakening the heat dissipation performance of the rotor core and the permanent magnet 3 and reducing the safety of the motor during operation. In the embodiment of this application, the rotor core adopts a split structure of inner core 1 and outer core 2. When the permanent magnet 3 is fixed to the outer surface of the inner core 1 with adhesive, the adhesive will not be scraped off, ensuring the fixing effect between the permanent magnet 3 and the inner core 1. Moreover, after the permanent magnet 3 is fixed to the inner core 1, it is convenient to clean up the excess adhesive, avoiding the heat dissipation problem of the rotor core and the permanent magnet 3 caused by overflowing adhesive, thus improving the safety of the motor during operation.

[0041] In some embodiments, the outer peripheral surface of the inner core 1 is provided with a first fixing surface 11 for fixing the permanent magnet 3, and the inner surface of the outer core 2 is provided with a second positioning surface 221 for limiting the permanent magnet 3, and a receiving groove is formed between the first fixing surface 11 and the second positioning surface 221.

[0042] In this application, after one side of the permanent magnet 3 is coated with glue, it is fixed on the first fixing surface 11 of the inner core 1. After the inner core 1 and the permanent magnet 3 are installed into the outer core 2, the permanent magnet 3 is limited by the second positioning surface 221 of the outer core 2 to ensure the fixing effect between the permanent magnet 3 and the rotor core.

[0043] Specifically, the permanent magnet 3 is mainly fixed to the inner iron core 1 with glue. There is a gap between the permanent magnet 3 and the second positioning surface 221 of the outer iron core 2 to ensure that the inner iron core 1 and the permanent magnet 3 can be assembled into the outer iron core 2.

[0044] In some embodiments, a first positioning protrusion 12 is provided on the outer peripheral surface of the inner core 1 along the axial direction of the inner core 1. The first positioning protrusion 12 is provided at the edge of the first fixing surface 11 and is used to position the permanent magnet 3 along the axial direction.

[0045] In this application, the first positioning protrusion 12 is arranged on the outer surface of the inner core 1 along the axial direction of the inner core 1. When the glued permanent magnet 3 is fixed to the first fixing surface 11 of the inner core 1, the permanent magnet 3 is positioned by abutting one end of the permanent magnet 3 with the first positioning protrusion 12, thereby ensuring the accuracy of fixing the permanent magnet 3 to the inner core 1.

[0046] Specifically, after the permanent magnet 3 is coated with adhesive, it is attached to the first fixing surface 11 of the inner core 1. One side of the permanent magnet 3 is attached to the edge of the first positioning protrusion 12, thereby fixing the permanent magnet 3 and ensuring that the permanent magnet 3 can be fixed along the axial direction of the inner core 1.

[0047] In this embodiment, the first positioning protrusion 12 can be set on one side edge of the first fixing surface 11 along the axial direction, which can complete the positioning of the permanent magnet 3 and ensure that the receiving groove has a sufficiently large space to install the permanent magnet 3; or the first positioning protrusion 12 can be set on both sides edge of the first fixing surface 11 along the axial direction respectively.

[0048] In some embodiments, the inner surface of the outer core 2 is provided with a second positioning protrusion 22 along the axial direction. The second positioning protrusion 22 is used to abut against the first positioning protrusion 12 so that the inner core 1 and the outer core 2 are positioned along the axial direction.

[0049] In this application, when the inner core 1 is assembled into the outer core 2, the end face of the first positioning protrusion 12 and the end face of the second positioning protrusion 22 are fitted together to position the inner core 1 and the outer core 2 axially, ensuring their coaxiality. Specifically, the first positioning protrusion 12 and the second positioning protrusion 22 can be arc surfaces. By fitting the arc surface of the first positioning protrusion 12 with the arc surface of the second positioning protrusion 22, the coaxiality of the inner core 1 and the outer core 2 can be achieved.

[0050] Specifically, the first positioning protrusion 12 and / or the second positioning protrusion 22 are provided with a slope structure at the ends along the axial direction, which facilitates the assembly of the inner core 1 into the outer core 2, and the fitting accuracy of the inner core 1 and the outer core 2 can be achieved through the first positioning protrusion 12 and the second positioning protrusion 22.

[0051] Furthermore, the side of the first positioning protrusion 12 facing the second positioning protrusion 22 has a first positioning surface 121, and the side of the second positioning protrusion 22 facing the first positioning protrusion 12 has a second positioning surface 221. The first positioning surface 121 is used to abut against the second positioning surface 221 so that the inner core 1 and the outer core 2 are positioned circumferentially.

[0052] In this application, the first positioning surface 121 of the first positioning protrusion 12 and the second positioning surface 221 of the second positioning protrusion 22 are attached to each other, so that the inner core 1 and the outer core 2 are positioned in the circumferential direction. Specifically, the first positioning surface 121 and the second positioning surface 221 are both planes. By attaching the first positioning surface 121 and the second positioning surface 221 with the plane structure, the assembly accuracy of the inner core 1 and the outer core 2 in the circumferential direction is controlled, thereby ensuring the size of the receiving groove between the inner core 1 and the outer core 2, and ensuring that the receiving groove can just accommodate the permanent magnet 3.

[0053] Optionally, the first positioning surface 121 and the second positioning surface 221 can also adopt a matching folded edge structure, which can also position the inner core 1 and the outer core 2 in the circumferential direction.

[0054] In some embodiments, the second positioning protrusion 22 is provided with a weight-reducing groove 222 on at least one side of the second positioning surface 221 about the axial direction.

[0055] In this application, the widths of the first positioning surface 121 and the second positioning surface 221 are kept consistent to ensure the contact area of ​​the first positioning surface 121 and the second positioning surface 221, thereby ensuring the effect of circumferential positioning of the inner core 1 and the outer core 2; by setting weight reduction grooves 222 on one or both sides of the second positioning protrusion 22, the material used for the rotor core is reduced, saving costs.

[0056] In some embodiments, the radial thickness d1 of the inner core 1 is ≥ 2 mm, and the radial thickness d2 of the outer core 2 is ≥ 2 mm.

[0057] In this application, for conventional permanent magnet motors currently on the market, the thickness of the inner core 1 and the outer core 2 is greater than or equal to 2mm to ensure the mechanical strength of the outer core 2 so as to facilitate the nesting and cooperation between the outer core 2 and the inner core 1. The layering position of the inner core 1 and the outer core 2 is set in the middle of the rotor core. The specific dimensions can be determined according to the specific structural dimensions and working conditions of the rotor core.

[0058] In some embodiments, a plurality of receiving slots are provided, and the plurality of receiving slots are evenly distributed along the circumference of the rotor core.

[0059] In this application, multiple receiving slots are evenly distributed along the circumference of the rotor core, and a set of permanent magnets 3 are fixed in each receiving slot; specifically, the number of receiving slots is 8, and the number of receiving slots can also be other numbers, which are not limited here.

[0060] The rotor core is divided into an inner core 1 and an outer core 2, which are coaxial. The permanent magnet 3 can be fixed on the outer surface of the inner core 1 first, and then the inner core 1 together with the permanent magnet 3 can be assembled into the outer core 2. This can effectively avoid the glue on the surface of the permanent magnet 3 being scraped off during the trial production process, ensure the bonding force between the core laminations, and thus ensure the stable and reliable operation of the permanent magnet motor.

[0061] This application provides a rotor assembly, including: the rotor core described above; and a permanent magnet 3 disposed in a receiving slot of the rotor core.

[0062] In this application, the rotor core of the rotor assembly includes an inner core 1 and an outer core 2. A receiving groove for accommodating the permanent magnet 3 is formed in the inner core 1 and the outer core 2. The inner core 1 and the permanent magnet 3 can be fixed first, and then the inner core 1 together with the permanent magnet 3 can be assembled into the outer core 2. This prevents the glue from being scraped off by the rotor core, thereby ensuring the bonding force between the permanent magnet 3 and the rotor core and ensuring the stable and reliable operation of the permanent magnet motor.

[0063] In some embodiments, the permanent magnet 3 in the receiving groove includes a plurality of permanent magnet units 31, which are arranged sequentially along the axial direction of the rotor core.

[0064] In this application, some rotor components have a relatively long rotor core along the axial direction, requiring multiple permanent magnet units 31 to be installed in each receiving slot. The multiple permanent magnet units 31 are arranged along the axial direction of the rotor core. Compared with an embedded integral rotor core, this application can facilitate the control of the fixing angle of the permanent magnet units 31 when fixing the permanent magnet units 31 and the inner core 1, and can also directly observe the contact of the end faces of the permanent magnet units 31, avoiding the situation where the end faces of the permanent magnet units 31 are not in contact during rotor trial production.

[0065] In some embodiments, the rotor assembly further includes two rotor end plates 4 and pins 5. The two rotor end plates 4 are respectively disposed at both ends of the rotor core along the axial direction, and the rotor end plates 4 are connected to the rotor core by the pins 5.

[0066] In this application, positioning holes are provided on the inner core 1 and the outer core 2 respectively. The pins 5 pass through the positioning holes of the inner core 1 and the outer core 2 respectively. The two ends of the pins 5 are connected to the rotor end plates 4. The inner core 1 and the outer core 2 are clamped and fixed by the rotor end plates 4 on both sides, so that the rotor assembly becomes a whole structure, avoiding axial relative movement between the inner core 1 and the outer core 2 during the operation of the motor, and further improving the safety and reliability of the motor during operation.

[0067] This application provides a permanent magnet motor, including the rotor assembly described above.

[0068] The permanent magnet motor rotor core in this application adopts a split structure, which facilitates the trial production of embedded rotors, increases the fault tolerance rate of rotor trial production, simplifies the process, and improves the safety of motor operation.

[0069] It should be understood that the terminology used herein is for the purpose of describing particular exemplary embodiments only and is not intended to be limiting. Unless the context clearly indicates otherwise, the singular forms “a,” “an,” and “described” as used herein may also include the plural forms. The terms “comprising,” “including,” “containing,” and “having” are inclusive and therefore indicate the presence of the stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof. The method steps, processes, and operations described herein are not construed as requiring them to be performed in a particular order described or illustrated unless the order of performance is explicitly indicated. It should also be understood that additional or alternative steps may be used.

[0070] Although terms such as first, second, third, etc., may be used in this document to describe multiple elements, components, regions, layers, and / or segments, these elements, components, regions, layers, and / or segments should not be limited by these terms. These terms may be used only to distinguish one element, component, region, layer, or segment from another. Unless the context clearly indicates otherwise, terms such as "first," "second," and other numerical terms used herein do not imply order or sequence. Therefore, the first element, component, region, layer, or segment discussed below may be referred to as the second element, component, region, layer, or segment without departing from the teachings of the exemplary embodiments.

[0071] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A rotor core, characterized in that, It includes an inner core (1) and an outer core (2) arranged coaxially. The outer core (2) is sleeved on the outer periphery of the inner core (1). A receiving groove for accommodating a permanent magnet (3) is formed between the outer core (2) and the inner core (1). The outer peripheral surface of the inner core (1) is provided with a first fixing surface (11) for fixing the permanent magnet (3), and the inner surface of the outer core (2) is provided with a second fixing surface (21) for limiting the permanent magnet (3). The receiving groove is formed between the first fixing surface (11) and the second fixing surface (21). The outer peripheral surface of the inner core (1) is provided with a first positioning protrusion (12) along the axial direction of the inner core (1). The first positioning protrusion (12) is located at the edge of the first fixed surface (11) and is used to position the permanent magnet (3) along the axial direction. The inner surface of the outer core (2) is provided with a second positioning protrusion (22) along the axial direction. The second positioning protrusion (22) abuts against the first positioning protrusion (12) so that the inner core (1) and the outer core (2) are positioned along the axial direction. The first positioning protrusion (12) has a first positioning surface (121) on the side facing the second positioning protrusion (22), and the second positioning protrusion (22) has a second positioning surface (221) on the side facing the first positioning protrusion (12). The first positioning surface (121) abuts against the second positioning surface (221) so that the inner core (1) and the outer core (2) are positioned circumferentially. The second positioning protrusion (22) has a weight-reducing groove (222) on at least one side of the second positioning surface (221) about the axial direction.

2. The rotor core according to claim 1, characterized in that, The inner core (1) has a radial thickness d1 ≥ 2 mm, and the outer core (2) has a radial thickness d2 ≥ 2 mm.

3. The rotor core according to claim 1 or 2, characterized in that, The receiving slots are provided in multiple ways, and the multiple receiving slots are evenly distributed along the circumference of the rotor core.

4. A rotor assembly, characterized in that, include: The rotor core as described in any one of claims 1 to 3; as well as The permanent magnet (3) is disposed in the receiving groove of the rotor core.

5. The rotor assembly according to claim 4, characterized in that, The permanent magnet (3) in the receiving groove includes multiple permanent magnet units (31), which are arranged sequentially along the axial direction of the rotor core.

6. The rotor assembly according to claim 4, characterized in that, The rotor assembly also includes two rotor end plates (4) and pins (5). The two rotor end plates (4) are respectively disposed at both ends of the rotor core along the axial direction. The rotor end plates (4) are connected to the rotor core through the pins (5).

7. A permanent magnet motor, characterized in that, Includes the rotor assembly as described in any one of claims 4 to 6.

Images