Vibration-damped motor shafts, permanent magnet motors and fans

Abstract

The present application relates to motor technology, and provides a vibration-damping motor shaft, a permanent magnet motor and a fan. The vibration-damping motor shaft includes: a first shaft body, a second shaft body and a vibration-damping sleeve. The first shaft body has a first connection portion at one end, and the first connection portion includes a plurality of first clamping claw blocks arranged in an annular manner around the axis; the second shaft body has a second connection portion at one end, and the second connection portion includes a plurality of second clamping claw blocks arranged in an annular manner around the axis; a plurality of the first clamping claw blocks and a plurality of the second clamping claw blocks are mutually clamped and fixed, one side of the vibration-damping sleeve matches the shape of the plurality of the first clamping claw blocks, and the other side of the vibration-damping sleeve matches the shape of the plurality of the second clamping claw blocks, and the vibration-damping sleeve is located between the clamping surface of the first connection portion and the clamping surface of the second connection portion. Thus, the vibration transmission path is separated, and the vibration transmission between the motor rotor, the load and the housing is avoided, so as to achieve the beneficial effect of vibration reduction of the whole motor.

Description

Technical Field

[0001] The present application relates to motor technology, and in particular to a vibration-damped motor shaft, a permanent magnet motor, and a fan. Background Art

[0002] With the development and advancement of permanent magnet motor technology, its application areas are becoming increasingly broad, and it is an indispensable part of air conditioners. Currently, air conditioners use motors and fan blades to supply air and dissipate heat, and motor vibration and noise are extremely important issues that need to be addressed urgently.

[0003] When the motor is operating, the vibrations generated by the rotating impeller and the rotor vibrations caused by the motor's electromagnetic force are transmitted through the bearings to the motor housing, which is then transmitted to the air conditioner. Resonance during this transmission process causes the vibrations transmitted to the entire unit to be greater, radiating noise outward. The rotor vibrations caused by the motor's electromagnetic force are transmitted to the fan blades, increasing their vibrations and leading to increased aerodynamic noise.

[0004] Although existing technologies offer a vibration reduction structure that uses a hydraulic damping device on the shaft for axial vibration reduction and a radial spring damping ring structure on the outer ring for radial vibration reduction, this type of existing structure complicates the manufacturing process and, due to the large radial movement space of the damping ring structure, is prone to dynamic eccentricity during motor operation, resulting in greater vibration. Summary of the Invention

[0005] In order to solve the technical problem of the complex vibration reduction structure and poor stability of the motor main shaft in the prior art, the present application provides a vibration reduction motor shaft, a permanent magnet motor and a fan.

[0006] In the first aspect, the present application provides a vibration-damping motor shaft, comprising: a first shaft body, one end of which has a first connecting portion, the first connecting portion including a plurality of first clamping claw blocks arranged in a ring around the axis; a second shaft body, one end of which has a second connecting portion, the second connecting portion including a plurality of second clamping claw blocks arranged in a ring around the axis; a plurality of first clamping claw blocks and a plurality of second clamping claw blocks are clamped and fixed to each other, and a vibration-damping sleeve, one side of which matches the shape of the plurality of first clamping claw blocks and the other side of which matches the shape of the plurality of second clamping claw blocks, the vibration-damping sleeve being located between the clamping surface of the first connecting portion and the clamping surface of the second connecting portion.

[0007] According to an embodiment of the present application, both the first clamping claw block and the second clamping claw block have one or more clamping surfaces extending from the axis to the periphery.

[0008] According to an embodiment of the present application, there is also a first sleeve, which is sleeved on the outer periphery of the first connecting part and the second connecting part to wrap and limit the first connecting part and the second connecting part at the outer periphery.

[0009] According to an embodiment of the present application, a plurality of top blocks are further provided on the inner side of the first sleeve, and the plurality of top blocks are distributed at intervals in the circumferential direction to press against the outer periphery of the first connecting portion and the second connecting portion in the radial direction.

[0010] According to an embodiment of the present application, a plurality of elastic members are further included to elastically push each of the top blocks toward the axial direction.

[0011] According to an embodiment of the present application, the first sleeve includes two roughly semicircular assembled bodies, and a bearing wraps around the outer circumference of the two assembled bodies to limit the position of the first sleeve.

[0012] According to an embodiment of the present application, there is a mutually limiting bite portion between the two assembling bodies to perform axial limitation between the two assembling bodies.

[0013] According to an embodiment of the present application, the outer diameter of the first connecting portion is greater than the outer diameter of the first shaft body, and the outer diameter of the second connecting portion is greater than the outer diameter of the second shaft body.

[0014] According to an embodiment of the present application, the inner side of the first sleeve has an anti-rotation engaging surface, and the outer peripheries of the first connecting portion and the second connecting portion have engaging surfaces that engage with the anti-rotation engaging surface.

[0015] According to an embodiment of the present application, the first sleeve further has a first axial limiting portion and a second axial limiting portion at both ends. The first axial limiting portion is matched and sleeved on the first shaft body, and the inner side of the axial limiting portion is clamped at the axial root of the first connecting portion; the second axial limiting portion is matched and sleeved on the second shaft body, and the inner side of the second axial limiting portion is clamped at the axial root of the second connecting portion.

[0016] According to an embodiment of the present application, a second vibration damping sleeve and a third vibration damping sleeve are further provided. The second vibration damping sleeve is located between the first axial limiting portion and the first connecting portion; the third vibration damping sleeve is located between the second axial limiting portion and the second connecting portion.

[0017] According to an embodiment of the present application, the second shaft body further has a shaft end portion, a second shaft sleeve is assembled outside the shaft end portion, and the second shaft sleeve is rotatably fixed outside by a bearing.

[0018] In a second aspect, the present application provides a permanent magnet motor, comprising the vibration-damping motor shaft as described above, wherein the vibration-damping motor shaft is the main shaft of the permanent magnet motor.

[0019] The above technical solution provided by the embodiment of the present application has the following advantages compared with the prior art:

[0020] In the embodiment of the present invention, the main shaft is divided into a first shaft body and a second shaft body that are assembled in an assembled manner. The two shaft bodies are axially clamped and assembled by a clamping claw block structure. At the same time, a vibration-damping sleeve is arranged between the clamping surfaces on both sides of the clamping block to absorb axial vibration. The vibration-damping sleeve forms a filler between the clamping surfaces on both sides. In other words, the vibration-damping sleeve made of elastic material can provide vibration reduction and seismic isolation effects, and also provides the function of elastic compensation for concentricity between the segmented shaft bodies. This separates the vibration transmission path, prevents the mutual transmission of vibration between the motor rotor, load, and housing, and achieves the beneficial effect of vibration reduction of the entire motor.

[0021] The claws extend all the way to the axis center, and the contact surface of the claw connection is the entire surface from the edge to the axis center, resulting in a larger contact area. Assuming that the overall external dimensions of the claws of the present invention and the prior art are consistent, and the claws are of the same length, only when the shaft is subjected to forces of the same magnitude and position will a force inversely proportional to the distance between the ends be generated on the claws, with the force being greatest at the ends. As the contact area increases, the average force on the vibration-damping rubber decreases, resulting in less deformation of the rubber and smaller relative displacement between the two shafts. The internal snap-fit ​​structure of the claws and the rubber filling ensure that there is virtually no gap inside. This structure also increases the rigidity of the rubber, providing both vibration reduction and position control.

[0022] By designing a combined vibration-damping shaft structure, the segmented shaft and bearing are connected by a claw-type structure and a bushing, and rubber and dampers are added between the shafts and between the shafts and bushings to reduce vibration, thereby separating the vibration transmission path and avoiding the mutual transmission of vibration between the motor rotor, load blades, and casing, thereby achieving the beneficial effect of vibration reduction of the entire motor. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0024] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, for ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative labor.

[0025] Figure 1 : Schematic diagram of the shaft structure decomposition of an embodiment of the present invention.

[0026] Figure 2 : Axial cross-sectional view of the motor front bearing vibration reduction structure according to an embodiment of the present invention.

[0027] Figure 3 : Radial cross section (along the radial direction) of the vibration reduction structure of the front bearing of the motor according to the embodiment of the present invention Figure 2Cross-sectional view (in the AA direction).

[0028] Figure 4 : Axial cross-sectional view of the motor rear bearing vibration reduction structure according to an embodiment of the present invention.

[0029] Among them, 1 is the first shaft body, 11 is the first connecting part, 12 is the first clamping claw block, 2 is the second shaft body, 21 is the second connecting part, 22 is the second clamping claw block, 23 is the shaft end, 3 is the first sleeve, 31 is the top block, 32 is the spring, 33 is the bite part, 34 is the first axial limiting part, 35 is the second axial limiting part, 4 is the second sleeve, 5 is the vibration damping sleeve, 51 is the second vibration damping sleeve, 52 is the third vibration damping sleeve, and 7 is the bearing. DETAILED DESCRIPTION

[0030] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0031] In order to solve the technical problem of the complexity and poor stability of the vibration reduction structure of the motor main shaft in the prior art, the embodiment of the present application mainly connects the segmented main shaft through the claw pole structure, and adds a vibration reduction sleeve between the clamping surfaces of the claw pole structure to absorb axial vibration. The vibration reduction sleeve forms a filler between the clamping surfaces on both sides, that is, the vibration reduction sleeve made of elastic material can provide vibration reduction and shock isolation effects, and also provides the function of elastic compensation of concentricity between the segmented shaft bodies. Thereby, the vibration transmission path is separated, and the mutual transmission of vibration between the motor rotor, load, and housing is avoided, thereby achieving the beneficial effect of vibration reduction of the entire motor. It can be understood by those skilled in the art that, based on the above basic technical ideas, there can be various deformations or form changes for the specific configuration scheme of the motor shaft. Obviously, these deformations or form changes should all fall within the scope of the technical ideas of the present application.

[0032] In the embodiment of the present application, the bearings at both ends of the motor are connected to the shaft vibration reduction structure, and the vibration paths of the three components of the motor housing, rotor, and fan blades are separated, reducing the mutual transmission of vibrations and thus reducing the vibration of the entire motor.

[0033] Specifically, see Figure 1A schematic diagram of the decomposed structure of the shaft body of an embodiment of the present invention. In the first aspect, the present application provides a vibration-damping motor shaft, which mainly includes: a first shaft body 1, a second shaft body 2, and a vibration-damping sleeve 5. One end of the first shaft body 1 has a first connecting portion 11, and the first connecting portion 11 includes a plurality of first clamping claw blocks 12 arranged in a ring around the axis. One end of the second shaft body 2 has a second connecting portion 21, and the second connecting portion 21 includes a plurality of second clamping claw blocks 22 arranged in a ring around the axis; the plurality of first clamping claw blocks 12 and the plurality of second clamping claw blocks 22 are clamped and fixed to each other, one side of the vibration-damping sleeve 5 matches the shape of the plurality of first clamping claw blocks 12, and the other side matches the shape of the plurality of second clamping claw blocks 22, and the vibration-damping sleeve is located between the clamping surface of the first connecting portion 11 and the clamping surface of the second connecting portion 21.

[0034] In this embodiment, the rubber thickness of the vibration-damping sleeve 5 between the side faces of the clamping claw block can be set to be thinner in the axial direction, while being thicker in the axial portion of the connecting end face to ensure better axial vibration damping. Furthermore, this wedge-shaped clamping claw block structure has a larger contact area and minimizes deformation under stress, ensuring good coaxiality between the two shaft sections while reducing the transmission of radial vibration between the two shaft sections.

[0035] According to an embodiment of the present application, each of the first engaging claw block 12 and the second engaging claw block 22 has one or more engaging surfaces extending from the axis toward the periphery. Specifically illustrated in the figure, each engaging claw block has two engaging surfaces, with an angle of less than 90 degrees between the two engaging surfaces. This allows these engaging surfaces to convert radial torque into a centripetal force component to maintain coaxiality. In this embodiment, there are three first engaging claw blocks 12 and three second engaging claw blocks 22, so the angle between the two engaging surfaces is selected to be 60 degrees.

[0036] Figure 2 : An axial cross-sectional view of the motor front bearing vibration reduction structure according to an embodiment of the present invention, and Figure 3 : Radial cross section (along the radial direction) of the vibration reduction structure of the front bearing of the motor according to the embodiment of the present invention Figure 2 (A cross-sectional view taken along the AA direction). According to an embodiment of the present application, a first sleeve 3 is further provided, which is sleeved over the outer periphery of the first connecting portion 11 and the second connecting portion 21 after they are engaged, thereby wrapping around and limiting the position of the first connecting portion 11 and the second connecting portion 21. In a specific embodiment, a plurality of top blocks 31 are further provided on the inner side of the first sleeve 3. The plurality of top blocks 31 are spaced apart in the circumferential direction to radially abut the outer periphery of the first connecting portion 11 and the second connecting portion 21. The top blocks 31 limit the position of each engaging claw block on the outer periphery.

[0037] It is understood that the first sleeve 3 can be an annular sleeve, and the inner surface of the first sleeve 3 can be aligned with the outer circumferential surface of the assembled first connecting portion 11 and the second connecting portion 21, so as to limit the two spliced ​​structures at the outer circumference. To facilitate assembly, the first sleeve 3 can also be a component that is assembled and combined in the axial direction.

[0038] The first sleeve 3 has an anti-rotation engagement surface on its inner side, while the first and second connecting portions 21 have engagement surfaces on their outer circumferences that engage with the anti-rotation engagement surface. In a specific embodiment, the anti-rotation engagement surface on the inner side of the first sleeve 3 is configured as an internal hexagonal shape to mate with the external hexagonal shape on the outer circumferences of the first and second connecting portions 11, 21. According to one embodiment of the present application, the first sleeve 3 also includes multiple elastic members 32 that elastically push against each of the top blocks 31 in the axial direction.

[0039] According to an embodiment of the present application, the first sleeve 3 includes two roughly semicircular assemblies to facilitate radial assembly. A bearing 7 can wrap around the outer periphery of the first sleeve 3 to limit the position of the two assemblies of the first sleeve 3. A mutually limiting bite portion 33 is provided between the two assemblies to provide axial positioning between the two assemblies. Specifically, the stepped bite portions 33 on a single assembly can be selected to be in opposite directions so that the two assemblies will not be axially misaligned after the bite portions are engaged.

[0040] According to an embodiment of the present application, the outer diameter of the first connecting portion 11 is greater than the outer diameter of the first shaft body 1 , and the outer diameter of the second connecting portion 21 is greater than the outer diameter of the second shaft body 1 .

[0041] According to an embodiment of the present application, the first sleeve 3 further has a first axial limiting portion 34 and a second axial limiting portion 35 at both ends. The first axial limiting portion 34 is matched and sleeved on the first shaft body 1, and the inner side of the axial limiting portion is clamped to the axial root of the first connecting portion 11; the second axial limiting portion 35 is matched and sleeved on the second shaft body 2, and the inner side of the second axial limiting portion 35 is clamped to the axial root of the second connecting portion 21.

[0042] According to an embodiment of the present application, a second vibration-damping sleeve 51 and a third vibration-damping sleeve 52 are further provided. The second vibration-damping sleeve 51 is located between the first axial limiter 34 and the first connecting portion 11, respectively; the third vibration-damping sleeve 52 is located between the second axial limiter 35 and the second connecting portion 21, and between the axial limiter and the second connecting portion. As shown in the figure, the second and third vibration-damping sleeves 51, 52 can also be formed as a necked-down sleeve to extend a distance on the shaft body, thereby achieving vibration reduction between the contact surfaces of the sleeves and the shaft body.

[0043] Figure 4 Axial cross-sectional view of the motor rear bearing vibration damping structure according to an embodiment of the present invention. According to an embodiment of the present application, the second shaft body 2 further comprises a shaft end 23, with a second sleeve 4 assembled outside the shaft end 23. The second sleeve 4 can also be comprised of two radially assembled bodies, which are positionally fixed by an engaging portion 43. The second sleeve 4 is rotatably fixed to the outside by a bearing 7.

[0044] In the embodiment of the present application, the connecting part between the sleeve and the shaft has a hexagonal cross-section with a small gap in the middle. A damping system consisting of a spring and a top block is provided on the inside of the sleeve to reduce vibration, thereby preventing vibration from being transmitted through the sleeve and reducing vibration transmitted through the bearing.

[0045] In the embodiment of the present application, the connecting parts of the first shaft body 1 and the second shaft body 2 are the first connecting part 11 and the second connecting part 21 of the same claw type. When matched, a small gap is left between the side surfaces of the first connecting part 11 and the second connecting part 21. A vibration-damping sleeve 5 made of rubber or flexible plastic is inserted between the first connecting part 11 and the second connecting part 21. The vibration-damping sleeve 5 at the side clamping part of the first connecting part 11 and the second connecting part 21 is relatively thin and is used for vibration reduction and maintaining the coaxiality of the shaft. The axial thickness of the vibration-damping sleeve 5 at the end surface connection of the first connecting part 11 and the second connecting part 21 is relatively thick, and has a good vibration reduction effect in the axial direction.

[0046] The assembly and use method of the shaft structure in the embodiment of the present application is schematically described as follows:

[0047] After the first and second shaft bodies 1 and 2 are connected, the vibration-damping sleeve 5 is installed first, followed by the first and second sleeves 3 and 4 at the connection. The contact surface between the first and second sleeves 3 and 4 features a trapezoidal structure to prevent displacement between them. A damper consisting of a top block 31 and an elastic member 32 is located between the first and second sleeves 3 and 4 and the first and second connecting portions 11 and 21, forming a radial vibration-damping structure. The bearing 7 is directly interference-fitted with the first or second sleeve 3 and 4, with the trapezoidal structure on the sleeve's outer periphery limiting the bearing's position.

[0048] At the position of the bearing 7 on the rear side, the end cross-section of the second shaft body 2 is also selected to be a hexagonal structure, and the second shaft sleeve 4 also has a trapezoidal structure to limit the bearing 7. The second shaft sleeve 4 and the second shaft body 2 are also separated by a damper consisting of a vibration-damping sleeve, a top block 31 and an elastic member 32 to separate the transmission path between the shaft and the housing, thereby reducing vibration transmission.

[0049] The present invention designs a combined vibration-damping shaft structure, connects the segmented shaft and the bearing through a claw-type structure and a shaft sleeve, and adds rubber and dampers between the shafts and between the shafts and the shaft sleeves for vibration reduction, thereby separating the vibration transmission path, avoiding the mutual transmission of vibration between the motor rotor, the load fan blades, and the housing, and achieving the beneficial effect of vibration reduction of the entire motor.

[0050] The claws of the present invention extend all the way to the center, and the contact surface of the claw connection extends from the edge to the axis center, resulting in a larger contact area. Assuming the overall external dimensions of the claws of the present invention and the prior art are identical, and the claws are of the same length, only when the shaft is subjected to forces of the same magnitude and position will a force inversely proportional to the distance between the ends be generated on the claws, with the force being greatest at the ends. A larger contact area reduces the average force on the vibration-damping rubber, resulting in less deformation of the rubber and smaller relative displacement between the two shafts. The internal snap-fit ​​structure of the claws and the rubber filling ensure a virtually gap-free interior. This structure also increases the rigidity of the rubber, providing both vibration reduction and position control.

[0051] There are vibration-damping rubber and damping blocks between the sleeve and the claw. When there is relative displacement between the two shafts, the rubber will take effect and generate a force opposite to the direction of shaft offset, thereby maintaining the coaxiality of the other layer and performing axial limiting to achieve the effect of limiting axial stringing.

[0052] On the other hand, after the embodiment of the present application performs local vibration reduction structure modification inside the shaft, it will not affect the spatial structural design of the motor housing and rotor, and will not affect the performance of the motor while improving noise and vibration.

[0053] In principle, the axial vibration reduction effect is mainly achieved through the rubber in the shaft connection part. There is a damper composed of a rubber layer and a top block spring between the shaft and the sleeve for vibration reduction. There is no direct contact between the various components. The sleeve and bearing of the vibration reduction structure have an interference fit, thereby isolating the vibration path of the casing, rotor and load fan blades, reducing the overall vibration of the motor.

[0054] The figures in this article are only schematic diagrams used to illustrate the working principle. The present invention does not limit the cross-sectional shape and size of the claw structure and the sleeve, nor does it limit the shape and number of the damper structure. Structures with similar functions can meet the application of the present invention.

[0055] In a second aspect, the present application provides a permanent magnet motor, comprising the vibration-damping motor shaft as described above, wherein the vibration-damping motor shaft is the main shaft of the permanent magnet motor.

[0056] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, an element defined by the phrase "comprising a ..." does not exclude the presence of other identical elements in the process, method, article, or device comprising the element.

[0057] The foregoing description is intended only to provide specific embodiments of the present invention, which will enable those skilled in the art to understand and implement the present invention. 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 the present invention. Therefore, the present invention is not intended to be limited to the embodiments shown herein, but is intended to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A vibration-damped motor shaft, characterized in that: include: A first shaft body (1), one end of which has a first connecting portion (11), the first connecting portion (11) comprising a plurality of first clamping claw blocks (12) arranged in an annular manner around the axis, the first clamping claw blocks (12) having a clamping surface extending from the axis to the periphery; A second shaft body (2) has a second connecting portion (21) at one end thereof, wherein the second connecting portion (21) comprises a plurality of second clamping claw blocks (22) arranged in a ring around the axis; the plurality of first clamping claw blocks (12) and the plurality of second clamping claw blocks (22) are mutually clamped and fixed; and a vibration-damping sleeve (5), one side of which matches the shape of the plurality of first clamping claw blocks (12), and the other side of which matches the shape of the plurality of second clamping claw blocks (22), the vibration-damping sleeve (5) being located between the clamping surface of the first connecting portion (11) and the clamping surface of the second connecting portion (21); A first sleeve (3) is sleeved on the outer circumference of the first connecting portion (11) and the second connecting portion (21) so as to wrap and position the first connecting portion (11) and the second connecting portion (21) at the outer circumference. A plurality of top blocks (31) are further provided on the inner side of the first sleeve (3). The plurality of top blocks (31) are spaced apart in the circumferential direction so as to abut against the outer circumference of the first connecting portion (11) and the second connecting portion (21) in the radial direction.

2. The vibration-damped motor shaft according to claim 1, characterized in that: The first clamping claw block (12) and the second clamping claw block (22) both have one or more clamping surfaces extending from the axis to the periphery.

3. The vibration-damped motor shaft according to claim 1, characterized in that: It also includes a plurality of elastic members (32) for elastically pushing each of the top blocks (31) toward the axial direction.

4. The vibration-damped motor shaft according to claim 1, characterized in that: The first shaft sleeve (3) comprises two semicircular annular assemblies, and a bearing (7) wraps around the outer circumference of the two assemblies to limit the position of the first shaft sleeve (3).

5. The vibration-damped motor shaft according to claim 4, characterized in that: There is a mutually limiting bite portion between the two assembling bodies to perform axial limiting between the two assembling bodies.

6. The vibration-damped motor shaft according to claim 1, characterized in that: The outer diameter of the first connecting portion (11) is greater than the outer diameter of the first shaft body (1), and the outer diameter of the second connecting portion (21) is greater than the outer diameter of the second shaft body (2).

7. The vibration-damped motor shaft according to claim 1, characterized in that: The first shaft sleeve (3) has an anti-rotation engagement surface on its inner side, and the first connecting portion (11) and the second connecting portion (21) have engagement surfaces on their outer peripheries that engage with the anti-rotation engagement surface.

8. The vibration-damped motor shaft according to claim 1, characterized in that: The first shaft sleeve (3) also has a first axial limiting portion (34) and a second axial limiting portion (35) at both ends; the first axial limiting portion (34) is matched and sleeved on the first shaft body (1), and the inner side of the axial limiting portion is clamped on the axial root of the first connecting portion (11); the second axial limiting portion (35) is matched and sleeved on the second shaft body (2), and the inner side of the second axial limiting portion (35) is clamped on the axial root of the second connecting portion (21).

9. The vibration-damped motor shaft according to claim 8, characterized in that: It also comprises a second vibration-damping sleeve (51) and a third vibration-damping sleeve (52), wherein the second vibration-damping sleeve (51) is located between the first axial limiting portion (34) and the first connecting portion (11); and the third vibration-damping sleeve (52) is located between the second axial limiting portion (35) and the second connecting portion (21).

10. The vibration-damped motor shaft according to any one of claims 1 to 9, characterized in that: The second shaft body (2) also has a shaft end (23), a second shaft sleeve (4) is assembled outside the shaft end (23), and the second shaft sleeve (4) is rotatably fixed outside via a bearing (7).

11. A permanent magnet motor, characterized in that: It comprises the vibration-damped motor shaft according to any one of claims 1 to 10, wherein the vibration-damped motor shaft is the main shaft of the permanent magnet motor.

12. A fan, characterized in that: It comprises the permanent magnet motor as claimed in claim 11, or it comprises the vibration reduction motor shaft as claimed in any one of claims 1 to 10.

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