Rotor core and assembled rotor

Abstract

The application discloses a rotor core and an assembled rotor, and belongs to the technical field of permanent magnet synchronous motors, wherein the rotor core comprises a core body, a plurality of structural members are uniformly and interval arranged in the core body, and the core body and the plurality of structural members are integrally pressure-cast; first installation cavities for filling permanent magnets are formed between adjacent structural members and the core body; and a second installation cavity for installing a rotating shaft is formed by the plurality of structural members in an overall enclosing manner. The core body and the structural members of the rotor core are integrally pressure-cast, the structural strength is high, batch production is easy, the size is controllable, the weight is lighter, the overall cost is lower, compared with the motor with the same power, the motor with the rotor core is smaller in size, the application range can be expanded, the assembled rotor is composed of the rotor core, a magnetic isolation sleeve, a rotating shaft and permanent magnets, and each component can form a standard accessory. When a certain component is damaged, the component can be replaced individually, and the rotor does not need to be replaced as a whole, so that the maintenance cost is reduced.

Description

Technical Field

[0001] This invention relates to the field of permanent magnet synchronous motor technology, and in particular to a rotor core and an assembled rotor. Background Technology

[0002] Permanent magnet synchronous motors mainly consist of a rotor, stator, and end covers. Stator windings are wound around the stator. By controlling the frequency of the input current to the stator windings, the rotation frequency of the magnetic field can be controlled, thereby controlling the speed. Permanent magnets are placed on the rotor. Depending on the placement of the permanent magnets, they are divided into protruding permanent magnet rotors and embedded permanent magnet rotors. The permanent magnets on the rotor provide excitation, eliminating the need for brushes and excitation current, which can improve the efficiency and power density of the motor. However, currently, most motors have internal rotors that are custom-installed by the manufacturer. If the rotor is damaged, the repair and replacement costs are high. Furthermore, existing motor rotors are relatively large, and high-power motors require even larger rotors, resulting in a large overall motor size, occupying space, and limiting the application range.

[0003] To address this, a rotor core and an assembled rotor are proposed. Summary of the Invention

[0004] The present invention aims to solve the problems mentioned in the background art by providing a rotor core and an assembled rotor.

[0005] The present invention achieves the above objectives through the following technical solutions:

[0006] A rotor core includes a core body, in which a plurality of structural components are evenly spaced, and the core body and the plurality of structural components are integrally die-cast; a first mounting cavity for filling permanent magnets is formed between adjacent structural components and the core body; the plurality of structural components are integrally enclosed to form a second mounting cavity for mounting a rotating shaft, and the first mounting cavity and the second mounting cavity are connected.

[0007] In this invention, the rotor core is integrally die-cast. Multiple first mounting cavities are opened inside the core to facilitate the installation of permanent magnets. Furthermore, magnetic isolation grooves are provided at the joints between the structural components and the core to reduce magnetic leakage. Compared to motors of the same power, motors using the rotor core of this invention are smaller in size, which can expand the range of applications.

[0008] Preferably, the structural component includes a tapered portion and an arc-shaped portion, one end of the tapered portion is connected to the core, and the other end of the tapered portion is connected to the arc-shaped portion.

[0009] Preferably, the width of the tapered portion near the core is greater than the width of the tapered portion near the arc-shaped portion, and the width of the arc-shaped portion is greater than the width of the tapered portion near the arc-shaped portion.

[0010] Preferably, the first mounting cavity is integrally formed between two adjacent sets of the conical portions, arc-shaped portions, and the inner wall of the core that overlaps with the conical portions.

[0011] Preferably, the included angles formed between the two sides of the tapered portion and the two sides of the overlapping arc-shaped portion are obtuse angles.

[0012] Preferably, a limiting area for securing the rotating shaft is formed between two adjacent sets of the arc-shaped portions.

[0013] Preferably, the junction between the tapered portion and the core is chamfered to form a magnetically shielding groove that cooperates with the permanent magnet.

[0014] The present invention also provides an assembled rotor, including a rotor core, a magnetic shielding sleeve passing through a second mounting cavity of the rotor core, a fastener provided on the magnetic shielding sleeve, the fastener passing through a limiting area of ​​the rotor core, the fastener cooperating with the arc-shaped portion to secure the magnetic shielding sleeve and prevent the magnetic shielding sleeve from rotating circumferentially; a rotating shaft passing through the magnetic shielding sleeve; a permanent magnet filling the first mounting cavity of the rotor core, and a magnetic shielding groove forming between the permanent magnet, the conical portion, and the core body.

[0015] The assembled rotor in this invention consists of four parts: rotor core, magnetic shielding sleeve, rotating shaft and permanent magnet. Each component can be formed into a standard accessory, which is convenient to assemble. In subsequent maintenance, if a certain component is damaged, it can be replaced individually without replacing the entire rotor.

[0016] Preferably, the fastener includes protrusions evenly spaced along the circumference of the magnetic shielding sleeve and extending toward the permanent magnet. The protrusions extend into the limiting area and cooperate with the permanent magnet to secure the permanent magnet in the first mounting cavity. A slot is formed between adjacent protrusions and on the magnetic shielding sleeve to accommodate the arc-shaped portion. Several arc-shaped portions are respectively inserted into the corresponding slots to secure the magnetic shielding sleeve in the second mounting cavity.

[0017] Preferably, the permanent magnet has a groove corresponding to the protrusion, and the protrusion is inserted into the groove.

[0018] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0019] 1. High structural strength and easy to manufacture: The rotor core and structural components are die-cast as a whole, resulting in high structural strength, easy mass production, controllable size, lighter weight, and lower overall cost.

[0020] 2. Reduce magnetic leakage: The conical part in the structural component has a chamfer at the joint with the core, forming a magnetic shielding groove, which can reduce the magnetic leakage of the permanent magnet.

[0021] 3. Small motor size and wide range of applications: Compared with motors of the same power, motors using this rotor core are smaller in size, which can expand their application range.

[0022] 4. Easy to maintain and replace: The assembled rotor consists of a rotor core, magnetic shielding sleeve, shaft, and permanent magnets, and each component can be made into standard parts. When a component is damaged, it can be replaced individually without replacing the entire rotor, thus reducing maintenance costs.

[0023] 5. Easy and stable assembly: The fasteners on the magnetic shielding sleeve can not only stably secure the magnetic shielding sleeve to the rotor core, but also secure the permanent magnet, realizing the mutual connection between the magnetic shielding sleeve, the permanent magnet and the rotor core, making the assembly more convenient and stable. Attached Figure Description

[0024] 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, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0025] Figure 1 This is a three-dimensional structural diagram of the core in this invention;

[0026] Figure 2 This is a schematic diagram of the planar structure of the core in this invention;

[0027] Figure 3 This is a schematic diagram of the three-dimensional assembly structure of the core, the magnetic shielding sleeve, and the permanent magnet in this invention;

[0028] Figure 4 This is a schematic diagram of the assembly planar structure of the core, the magnetic shielding sleeve, and the permanent magnet in this invention;

[0029] Figure 5 This is a schematic diagram of the overall assembly structure of the core, magnetic shielding sleeve, and rotating shaft in this invention;

[0030] Figure 6 This is a three-dimensional structural diagram of the rotating shaft in this invention;

[0031] Figure 7 This is a three-dimensional structural schematic diagram of the magnetic shielding sleeve in this invention;

[0032] Figure 8 This is a schematic diagram of the planar structure of the magnetic shielding sleeve in this invention;

[0033] Figure 9 This is a three-dimensional structural diagram of the permanent magnet in this invention;

[0034] Figure 10 This is a schematic diagram of the structure of the permanent magnet after the assembly of the core, the magnetic shielding sleeve, and the permanent magnet in this invention, and the subsequent extraction of the permanent magnet. Figure 1 ;

[0035] Figure 11 This is a schematic diagram of the structure of the permanent magnet after the assembly of the core, the magnetic shielding sleeve, and the permanent magnet in this invention, and the subsequent extraction of the permanent magnet. Figure 2 ;

[0036] Figure 12 This is another perspective schematic diagram of the overall assembly structure of the core, magnetic shielding sleeve, and rotating shaft in this invention.

[0037] Figure 13 This is a schematic diagram of the assembly structure of the magnetic insulating sleeve and the rotating shaft in this invention.

[0038] The annotations in the attached figures are explained as follows:

[0039] 1. Core; 2. Structural component; 3. First mounting cavity; 4. Second mounting cavity; 5. Conical part; 6. Arc-shaped part; 7. Chamfer; 8. Magnetic shielding sleeve; 9. Protrusion; 10. Slot; 11. Rotating shaft; 12. Boss; 13. Permanent magnet. Detailed Implementation

[0040] The following is in conjunction with the appendix Figure 1-12 The technical solution of the present invention will be further explained below:

[0041] Example 1

[0042] like Figure 1 and Figure 2 As shown, this embodiment provides a rotor core, including a core body 1, with a plurality of structural components 2 evenly spaced inside the core body 1. The core body 1 and the structural components 2 are integrally die-cast. In other words, this embodiment arranges structural components at intervals inside a cylindrical core, and the cylindrical core and structural components are integrally die-cast, resulting in high structural strength, ease of mass production, controllable dimensions, and, compared to traditional rotor core designs, lighter weight and lower overall cost.

[0043] Specifically, in this embodiment, such as Figure 2 As shown, a first mounting cavity 3 for filling permanent magnets 13 is formed between adjacent structural components 2 and the core 1. That is, a first mounting cavity is integrally formed between two adjacent structural components and the inner wall of the core. During subsequent rotor assembly, permanent magnets 13 are filled into the first mounting cavity. The permanent magnets 13 are made of magnets such as magnetic steel.

[0044] It should be noted that the first mounting cavity 3 also has an empty area to reduce the magnetic leakage of the permanent magnet 13. The permanent magnet 13 does not completely fill the first mounting cavity 3. That is, there is an unfilled area between the permanent magnet 13 and the structural component and the core, which serves as an empty cavity to reduce the magnetic leakage of the permanent magnet 13.

[0045] That is, Figure 2 As shown, a chamfer 7 is provided at the junction of the tapered portion 5 and the core 1 in structural component 2 to form a magnetic isolation groove that cooperates with the permanent magnet 13. That is, a rounded corner is used at the junction of the tapered portion and the core, which is inside the first mounting cavity. When the permanent magnet block is filled, the chamfered position is not filled, thus forming a gap to reduce magnetic leakage.

[0046] Specifically, in this embodiment, such as Figure 2 As shown, several structural components 2 are integrally enclosed to form a second mounting cavity 4 for mounting the rotating shaft, and the first mounting cavity 3 is connected to the second mounting cavity 4. That is to say, the area formed by the integral enclosing of the ends of each structural component away from the core is the second mounting cavity. The second mounting cavity is used to fill the rotating shaft, and the second mounting cavity is connected to the first mounting cavity to facilitate the subsequent installation of the rotating shaft into the sleeve. The whole assembly makes the rotor core, permanent magnet 13 and sleeve nested together and locked in place.

[0047] In some embodiments, such as Figure 1 and Figure 2 As shown, structural component 2 includes a conical portion 5 and an arc-shaped portion 6. One end of the conical portion 5 is connected to the core 1, and the other end of the conical portion 5 is connected to the arc-shaped portion 6. That is, in this embodiment, 10 structural components are evenly spaced inside the core. Each structural component consists of a conical support portion and an arc-shaped limiting portion. The conical support portion, as the part directly connected to the core, bears the main load-bearing function. The cross-sectional width of the conical portion gradually decreases towards the arc-shaped portion, and the width of the conical portion directly overlapping the core is the largest, ensuring the connection strength between the conical portion and the core. The arc-shaped limiting portion adopts an extension section and an arc-shaped limiting section. The extension section, as an intermediate body overlapping the conical portion, ensures the connection strength between the arc-shaped limiting section and the conical portion. The arc-shaped contact surface at the end of the arc-shaped limiting section is used to abut against the sleeve during rotor assembly, for securing the sleeve of the rotating shaft.

[0048] In some embodiments, such as Figure 2 As shown, the width of the tapered portion 5 near the core is greater than the width of the tapered portion 5 near the arc-shaped portion 6, and the width of the arc-shaped portion 6 is greater than the width of the tapered portion 5 near the arc-shaped portion 6. In other words, the cross-sectional width at the overlap between the tapered portion and the core is the largest, meaning the tapered portion and the core use a larger overlap surface to ensure the connection strength between the tapered portion and the core. Furthermore, the cross-sectional width of the tapered portion gradually decreases towards the direction away from the core, and the width at the overlap between the tapered portion and the extended section of the arc-shaped portion is smaller than the width of the extended section.

[0049] In some embodiments, the included angles formed between the two side surfaces of the tapered portion 5 and the two side surfaces of the overlapping arc portion 6 are obtuse angles. That is to say, the included angle at the overlapping portion of the tapered portion and the extended segment in the arc portion is an obtuse angle. On the one hand, the bent portion between the tapered portion and the extended segment can play a certain limiting and supporting role for the permanent magnet 13. On the other hand, it is necessary to ensure that when the rotor is assembled subsequently, the arc-shaped limiting segment in the arc portion can be inserted and abutted against the sleeve of the rotating shaft.

[0050] As Figure 2 shown, and a limiting area for clamping the rotating shaft is formed between two adjacent groups of arc portions 6. That is to say, the extended segments of two adjacent arc portions cooperate with each other, making the area between the two extended segments smaller, which is convenient for the clamping member on the sleeve of the rotating shaft to extend into the area between the two extended segments for clamping when the rotor is assembled subsequently.

[0051] Specifically, in this embodiment, as Figure 2 shown, a first installation cavity 3 is integrally formed among two adjacent groups of tapered portions 5, arc portions 6, and the inner wall of the core body 1 overlapping with the tapered portion. That is to say, a first installation cavity is enclosed among two tapered portions, the two corresponding connected arc portions, and the core body.

[0052] Embodiment Two

[0053] As Figure 3-5 and Figure 7-13 shown, the difference between this embodiment and Embodiment One is to provide an assembled rotor, including a rotor core. A magnetic isolation sleeve 8 is inserted through the second installation cavity 4 of the rotor core. A clamping member is provided on the magnetic isolation sleeve 8. The clamping member penetrates through the limiting area of the rotor core and cooperates with the arc portion to clamp the magnetic isolation sleeve to prevent the magnetic isolation sleeve from rotating circumferentially. That is to say, when the rotor is assembled, the magnetic isolation sleeve is placed into the second installation cavity of the rotor core. The clamping members on the magnetic isolation sleeve are respectively inserted into the limiting areas of the corresponding first installation cavities, and the clamping members abut against the arc-shaped limiting segments of the arc portion, so that the magnetic isolation sleeve is stably clamped in the rotor core. At this time, the magnetic isolation sleeve can be pulled out back and forth, but cannot rotate circumferentially, that is, the rotor core and the magnetic isolation sleeve maintain synchronous circumferential rotation.

[0054] As Figure 4 shown, the clamping member includes protruding portions 9 arranged at equal intervals along the circumferential direction of the magnetic isolation sleeve 8 and extending towards the direction close to the permanent magnet 13. The protruding portions 9 extend into the limiting area and cooperate with the permanent magnet 13 to clamp the permanent magnet in the first installation cavity 3. That is to say, protruding portions are uniformly arranged at equal intervals on the outer circumference of the magnetic isolation sleeve. The overall cross-sectional shape of the protruding portion is convex. The protruding portion extends into the position of the limiting area in the first installation cavity, and the protruding portion abuts against and clamps the permanent magnet 13 at the same time, fixing the permanent magnet 13 in the first installation cavity.

[0055] In some embodiments, the permanent magnet 13 has a groove corresponding to the protrusion 9, and the protrusion 9 is inserted into the groove. That is, by utilizing the groove on the permanent magnet 13, the protrusion on the magnetic shielding sleeve extends into the limiting area and is simultaneously inserted into the groove on the permanent magnet 13, thus securing the permanent magnet 13 in the first mounting cavity, preventing the permanent magnet 13 from shifting and avoiding vibration and demagnetization of the permanent magnet 13.

[0056] Furthermore, the first mounting cavity 3 of the rotor core is filled with permanent magnets 13, and a magnetic isolation groove is formed between the permanent magnets 13, the conical part, and the core. That is, a rounded corner is used at the junction of the conical part and the core, which is inside the first mounting cavity. When the permanent magnet is filled, the rounded corner is not filled, thus forming a gap to reduce magnetic leakage.

[0057] like Figure 4 As shown, slots 10 for accommodating arc-shaped portions are formed between adjacent protrusions 9 and on the magnetic shielding sleeve 8. Several arc-shaped portions 6 are respectively inserted into the corresponding slots 10 to secure the magnetic shielding sleeve 8 in the second mounting cavity 4. That is, slots that bend away from the arc-shaped portions are opened between adjacent protrusions. When the magnetic shielding sleeve is placed in the second mounting cavity, the protrusions extend into the first limiting cavity. At this time, the arc-shaped limiting section of the arc-shaped portion is inserted into the slot, thereby securing the magnetic shielding sleeve. In this embodiment, the fasteners on the magnetic shielding sleeve not only stably secure the magnetic shielding sleeve to the rotor core, but also secure the permanent magnet 13, thus achieving mutual nesting between the magnetic shielding sleeve, the permanent magnet 13, and the rotor core.

[0058] Specifically, such as Figure 5-6 As shown, a rotating shaft 11 is inserted inside the magnetic shielding sleeve 8; that is, the rotating shaft is inserted inside the magnetic shielding sleeve. When the rotating shaft is inserted into the magnetic shielding sleeve, it is a split type. In other words, when the rotating shaft is a split type, it can be pulled out from the magnetic shielding sleeve. When assembling the rotor, the rotating shaft and the magnetic shielding sleeve are installed by heat fitting or cold pressing.

[0059] In other words, the rotating shaft 11 and the magnetic shielding sleeve 8 adopt a split structure. The split structure reduces maintenance and replacement costs. Specifically, the rotating shaft is provided with an annular boss 12 that abuts against the magnetic shielding sleeve. The part of the rotating shaft that passes through the magnetic shielding sleeve is provided with a boss 12 that protrudes outward along the radial direction of the rotating shaft. During assembly, it is installed by heat fitting or cold pressing, and the rotating shaft boss and the magnetic shielding sleeve are tightly abutted against each other.

[0060] In summary, the present invention has the following technical effects:

[0061] 1. High structural strength and easy to manufacture: The rotor core 1 and structural component 2 are die-cast as a whole, which has high structural strength, is easy to mass-produce, has controllable size, lighter weight, and lower overall cost.

[0062] 2. Reduce magnetic leakage: The conical part 5 in the structural component 2 has a chamfer 7 at the joint with the core 1 to form a magnetic shielding groove, which can reduce the magnetic leakage of the permanent magnet 13.

[0063] 3. Small motor size and wide range of applications: Compared with motors of the same power, motors using this rotor core are smaller in size, which can expand their application range.

[0064] 4. Easy to maintain and replace: The assembled rotor consists of a rotor core, a magnetic shielding sleeve 8, a rotating shaft 11, and a permanent magnet 13. Each component can be made into a standard spare part. When a component is damaged, it can be replaced individually without replacing the entire rotor, thus reducing maintenance costs.

[0065] 5. Easy and stable assembly: The fasteners on the magnetic shielding sleeve 8 can not only stably secure the magnetic shielding sleeve 8 to the rotor core, but also secure the permanent magnet 13, realizing the mutual connection between the magnetic shielding sleeve 8, the permanent magnet 13 and the rotor core, making the assembly more convenient and stable.

[0066] The working principle of this invention is as follows:

[0067] 1. Magnetic circuit design of the rotor core: Structural components 2 are evenly spaced within the core body 1 of the rotor core. A first mounting cavity 3 is formed between adjacent structural components 2 and the core body 1, which is used to fill permanent magnets 13, and the permanent magnets 13 provide excitation. A second mounting cavity 4 is formed between several structural components 2, which is used to mount the rotating shaft 11, and the first mounting cavity 3 and the second mounting cavity 4 are connected.

[0068] 2. Magnetic Isolation and Fixing Function: Structural component 2 includes a tapered portion 5 and an arc-shaped portion 6. The chamfer 7 at the overlap between the tapered portion 5 and the core 1 forms a magnetic isolation groove to reduce magnetic leakage. The magnetic isolation sleeve 8 passes through the second mounting cavity 4, and its fixing fastener passes through the limiting area of ​​the rotor core, cooperating with the arc-shaped portion 6 to prevent the magnetic isolation sleeve 8 from rotating circumferentially. The protruding portion 9 of the fixing fastener extends into the limiting area and cooperates with the permanent magnet 13 to fix the permanent magnet 13 in the first mounting cavity 3. At the same time, the groove 10 between adjacent protruding portions 9 accommodates the arc-shaped portion 6, further fixing the magnetic isolation sleeve 8.

[0069] 3. Power transmission: The rotating shaft 11 is installed inside the magnetic shielding sleeve 8 by heat fitting or cold pressing. The boss 12 on the rotating shaft 11 abuts against the magnetic shielding sleeve 8 to realize power transmission.

[0070] The method of using this invention is as follows:

[0071] 1. Install the rotor core: Prepare the rotor core, whose core body 1 has a structural component 2 integrally die-cast inside, forming the first mounting cavity 3 and the second mounting cavity 4.

[0072] 2. Install the magnetic shielding sleeve: Insert the magnetic shielding sleeve 8 into the second mounting cavity 4 of the rotor core, so that the fastener on the magnetic shielding sleeve 8 extends into the limiting area between the adjacent arc-shaped parts 6 of the rotor core, and the arc-shaped parts 6 are inserted into the slot 10 of the magnetic shielding sleeve 8. The fastener cooperates with the arc-shaped parts 6 to lock the magnetic shielding sleeve 8 and prevent it from rotating circumferentially.

[0073] 3. Install permanent magnet 13: Fill the first mounting cavity 3 with permanent magnet 13, and form a magnetic isolation groove between permanent magnet 13, tapered part 5 and core 1. At the same time, the groove on permanent magnet 13 corresponds to the protrusion 9 of the fastener of magnetic isolation sleeve 8, and the protrusion 9 is inserted into the groove to secure permanent magnet 13.

[0074] 4. Install the rotating shaft: Insert the rotating shaft 11 into the magnetic shielding sleeve 8, and use hot fitting or cold pressing to make the boss 12 on the rotating shaft 11 fit tightly against the magnetic shielding sleeve 8, thus completing the assembly of the assembled rotor.

[0075] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An assembled rotor, characterized in that, It includes a rotor core, a magnetic shielding sleeve (8), a rotating shaft (11), and a permanent magnet (13). The rotor core includes a core body (1), and a plurality of structural components (2) are evenly spaced inside the core body (1). The core body (1) and the plurality of structural components (2) are integrally die-cast. A first mounting cavity (3) for filling permanent magnets (13) is formed between adjacent structural components (2) and the core body (1). A second mounting cavity (4) for mounting the rotating shaft (11) is formed by the integral enclosure of the plurality of structural components (2). The first mounting cavity (3) and the second mounting cavity (4) are connected. The structural component (2) includes a tapered portion (5) and an arc-shaped portion (6). One end of the tapered portion (5) is connected to the core (1), and the other end of the tapered portion (5) is connected to the arc-shaped portion (6). The width of the tapered portion (5) near the core (1) is greater than the width of the tapered portion (5) near the arc-shaped portion (6), and the width of the arc-shaped portion (6) is greater than the width of the tapered portion (5) near the arc-shaped portion (6). The angle formed between the two sides of the conical part (5) and the two sides of the overlapping arc-shaped part (6) is an obtuse angle; a limiting area for securing the magnetic shielding sleeve (8) is formed between two adjacent sets of arc-shaped parts (6); a chamfer (7) is provided at the overlap of the conical part (5) and the core (1) to cooperate with the permanent magnet (13) to form a magnetic shielding groove; The magnetic shielding sleeve (8) is inserted into the second mounting cavity (4) of the rotor core. A fastener is provided on the magnetic shielding sleeve (8), which is inserted into the limiting area of ​​the rotor core. The fastener cooperates with the arc-shaped portion (6) to secure the magnetic shielding sleeve (8) and prevent it from rotating circumferentially. The rotating shaft (11) is inserted into the magnetic shielding sleeve (8), and the rotating shaft (11) and the magnetic shielding sleeve... The cylinder (8) has a split structure. The outer wall of the rotating shaft (11) is provided with an annular boss (12). The annular boss (12) abuts against the end face of the magnetic shielding sleeve (8). The rotating shaft (11) and the magnetic shielding sleeve (8) are fixedly connected by heat fitting or cold pressing. The permanent magnet (13) is filled in the first mounting cavity (3) of the rotor core, and the magnetic shielding groove is formed between the permanent magnet (13), the tapered part (5), and the core (1). The fastener includes protrusions (9) evenly spaced along the circumference of the magnetic sleeve (8) and extending toward the permanent magnet (13). The protrusions (9) extend into the limiting area and cooperate with the permanent magnet (13) to secure the permanent magnet (13) in the first mounting cavity (3). Slots (10) for accommodating the arc-shaped portions (6) are formed between adjacent protrusions (9) and on the magnetic sleeve (8). A plurality of arc-shaped portions (6) are respectively inserted into the corresponding slots (10) to secure the magnetic sleeve (8) in the second mounting cavity (4). The permanent magnet (13) has a groove corresponding to the protrusion (9), and the protrusion (9) is inserted into the groove.

Images