A motor rotor, a magnetic levitation motor and a method of installing the same

Abstract

This invention discloses a motor rotor, a magnetic levitation motor, and its installation method. The motor rotor includes a rotor and a sliding sleeve. The sliding sleeve is clearance-fitted with the rotor to form a medium flow channel between the inner side of the sliding sleeve and the outer side of the rotor. The sliding sleeve has a medium inlet and a medium outlet. Cooling medium enters the medium flow channel through the medium inlet and flows out through the medium outlet, thereby suspending the rotor within the sliding sleeve. By implementing this invention, when the rotor rotates at high speed, under the action of gyroscopic effect, fluid viscosity, and fluid pressure, it will stably suspend at the center position of the axis of rotation. The entire rotor rotates without mechanical contact with the sliding sleeve, thus suspending the rotor within the sliding sleeve. At the same time, the cooling medium will remove the heat from the rotor and the stator core, ensuring that the permanent magnet operates within a good temperature range, improving heat dissipation and extending service life.

Description

Technical Field

[0001] This invention relates to the field of motor technology, and in particular to a motor rotor, a magnetic levitation motor, and a method for installing the same. Background Technology

[0002] Magnetic levitation motors utilize the electromagnetic force of magnetic bearings to levitate the motor rotor in mid-air, eliminating mechanical contact and friction between the rotor and stator, resulting in low-loss, high-performance motors. Existing motor rotor structures consist of permanent magnets and rotor sleeves. Since the permanent magnets are fully enclosed within the rotor sleeves, theoretically, the main magnetic flux and rotor rotation speed are the same during high-speed operation. However, due to spatial and temporal harmonics generated by stator teeth, alternating power supply, etc., their rotation speed differs from the rotor's. This induces an electromotive force in the rotor sleeve and permanent magnets, generating eddy currents and resulting in rotor eddy current losses. Therefore, significant eddy current losses exist in the permanent magnets and rotor sleeves. Over prolonged operation, the permanent magnets and rotor sleeves generate substantial heat, leading to temperature increases. Excessive temperature can cause performance degradation of the permanent magnets, even demagnetization, resulting in rotor failure and motor unusable. Furthermore, excessive temperature can cause excessive deformation of the rotor's outer circumference, leading to rotor eccentricity, poor levitation accuracy, abnormal vibration, and affecting stable rotor operation. Summary of the Invention

[0003] The embodiments of the present invention provide a motor rotor, a magnetic levitation motor and its installation method, aiming to solve the problems of high eddy current loss and excessively high temperature of existing magnetic levitation motors.

[0004] The present invention provides an electric motor rotor, including a rotor and a sliding sleeve. The sliding sleeve is clearance-fitted with the rotor to form a medium flow channel between the inner side of the sliding sleeve and the outer side of the rotor. The sliding sleeve is provided with a medium inlet and a medium outlet. Cooling medium enters the medium flow channel through the medium inlet and flows out through the medium outlet to suspend the rotor within the sliding sleeve.

[0005] In the motor rotor provided by the present invention, the rotor includes an upper short shaft, a lower short shaft, a permanent magnet, and a sheath. The upper short shaft and the lower short shaft are respectively located at both ends of the permanent magnet. The upper short shaft, the lower short shaft, and the permanent magnet are all interference-fitted with the sheath.

[0006] In the motor rotor provided by the present invention, the sliding sleeve includes an upper sliding sleeve and a lower sliding sleeve. The upper sliding sleeve is provided with the medium inlet, and the lower sliding sleeve is provided with the medium outlet. The upper sliding sleeve covers the upper short shaft and part of the protective sleeve, and the lower sliding sleeve covers the lower short shaft and another part of the protective sleeve. The end face of the upper sliding sleeve away from the medium inlet is in contact with the end face of the lower sliding sleeve away from the medium outlet.

[0007] In the motor rotor provided by the present invention, both the upper short shaft and the lower short shaft include a front conical section, the front conical section is located at the end away from the permanent magnet, the upper sliding sleeve is adapted to the shape of the upper short shaft, and the lower sliding sleeve is adapted to the shape of the lower short shaft.

[0008] In the motor rotor provided by the present invention, both the upper short shaft and the lower short shaft further include a rear cylinder section. The two ends of the rear cylinder section are connected to the front conical section and the permanent magnet. The diameter of the rear cylinder section is equal to the diameter of the permanent magnet. The sheath is interference-fitted with the rear cylinder section and the permanent magnet.

[0009] In the motor rotor provided by the present invention, the medium inlet includes a hollow cylinder and a first through hole. The cylinder is located at the top of the upper sliding sleeve, and the first through hole is opened at the top of the upper sliding sleeve and is located in the vertical projection plane of the cylinder.

[0010] In the motor rotor provided by the present invention, a tool holder mounting port is provided on the front tapered section of the lower short shaft, and the medium outlet is opened at the bottom end of the lower sleeve around the tool holder mounting port.

[0011] In the motor rotor provided by the present invention, the cone angle of the front cone section is 10°≤θ≤30°.

[0012] In the motor rotor provided by the present invention, the radius of the front conical section is r, and the diameter of the end of the front conical section connected to the rear cylindrical section is D, where 0.3≤2r / D≤0.7.

[0013] In the motor rotor provided by the present invention, the side wall of the upper sliding sleeve is provided with a first limiting part, and the side wall of the lower sliding sleeve is provided with a second limiting part. The first limiting part and the second limiting part are used to be fixed on the end faces of the shaft holes at both ends of the stator core.

[0014] The present invention also provides a magnetic levitation motor, including a motor rotor and a motor stator, wherein the motor rotor is the aforementioned motor rotor, and the motor rotor is rotatably disposed in the motor stator.

[0015] The present invention also provides a method for installing a magnetic levitation motor, the method comprising: interlocking an upper short shaft, a permanent magnet, a lower short shaft, and a protective sleeve into a whole to form a motor rotor; fixing a lower sliding sleeve to one end of a shaft hole in a stator core, and inserting the motor rotor into the shaft hole; fixing an upper sliding sleeve to the other end of a shaft hole in a stator core to together with the upper sliding sleeve to fit the motor rotor.

[0016] This invention provides a motor rotor, a magnetic levitation motor, and an installation method thereof. The motor rotor includes a rotor and a sliding sleeve. The sliding sleeve and the rotor are clearance-fitted, thereby forming a medium flow channel between the inner side of the sliding sleeve and the outer side of the rotor. A medium inlet and a medium outlet are provided on the sliding sleeve, allowing the cooling medium to enter the medium flow channel from the medium inlet and flow out from the medium outlet. Thus, when the rotor rotates at high speed, under the action of gyroscopic effect, fluid viscosity, and fluid pressure, it will be stably suspended at the center position of the axis of rotation. The entire rotor rotates without mechanical contact with the sliding sleeve, thereby suspending the rotor within the sliding sleeve. At the same time, the cooling medium will remove the heat from the rotor and the heat generated by the stator core, ensuring that the permanent magnet operates within a good temperature range, improving heat dissipation, and extending service life. Attached Figure Description

[0017] To more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings used in the following description of the embodiments will be briefly introduced. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the motor rotor according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of the rotor of the motor rotor according to an embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the sliding sleeve of the motor rotor according to an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram of the upper short shaft of the motor rotor according to an embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of the lower short shaft of the motor rotor according to an embodiment of the present invention;

[0023] Figure 6 This is a schematic diagram of the upper sliding sleeve of the motor rotor according to an embodiment of the present invention;

[0024] Figure 7 This is a schematic diagram of the lower sliding sleeve of the motor rotor according to an embodiment of the present invention;

[0025] Figure 8 This is a three-dimensional schematic diagram of the magnetic levitation motor according to an embodiment of the present invention;

[0026] Figure 9 for Figure 8 A magnified view of a portion of the image;

[0027] Figure 10 for Figure 8 Another enlarged view of a portion;

[0028] Figure 11 for Figure 1 A magnified view of a portion of the image;

[0029] Figure 12 for Figure 1 Another enlarged view of a portion;

[0030] Figure 13 This is a schematic diagram of the motor stator of the magnetic levitation motor according to an embodiment of the present invention;

[0031] Figure 14 This is a schematic diagram of a magnetic levitation motor according to an embodiment of the present invention;

[0032] Figure 15 This is a flowchart illustrating the steps of the installation method for a magnetic levitation motor according to an embodiment of the present invention;

[0033] Explanation of reference numerals in the attached figures:

[0034] 1. Motor rotor; 11. Rotor; 111. Upper short shaft; 1111. First front conical section; 1112. First rear cylindrical section; 112. Lower short shaft; 1121. Second front conical section; 1122. Second rear cylindrical section; 1123. Tool holder mounting port; 113. Permanent magnet; 114. Sheath; 115. Tool holder; 12. Sliding sleeve; 121. Upper sliding sleeve; 1211. Medium inlet; 1211a. Cylinder; 1211b. First through hole; 1212. First limiting part; 122. Lower sliding sleeve; 1221. Medium outlet; 1222. Second limiting part; 13. Medium flow channel; 2. Motor stator; 21. Stator core; 22. Stator winding; 23. Shaft hole. Detailed Implementation

[0035] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0036] The directional terms used in this invention, such as "up," "down," "front," "back," "left," "right," "inner," "outer," and "side," are merely for reference to the accompanying drawings. Therefore, the directional terms used are for illustrating and understanding this invention, and not for limiting it. Furthermore, in the drawings, structures that are similar or identical are indicated by the same reference numerals.

[0037] First, it should be noted that the embodiments of this invention mainly utilize the principle of sliding bearings, combined with the characteristics of high-speed motors, fluid dynamics, and high-speed rotor dynamics, and are designed according to market demands for miniaturized, ultra-high-speed, ultra-lightweight, and ultra-high-precision spindle motors. Sliding bearings are divided into hydrostatic bearings and hydrodynamic bearings. Hydrostatic bearings: These use a pressure pump to forcibly pump pressure lubricant into the tiny gap between the bearing and the shaft. Hydrodynamic bearings: These rely on the shape and relative movement of the sliding surfaces on the journal and the inner wall of the bearing, or structures such as bearing pads that can automatically adjust their slope according to changes in load and speed, to form a fluid film that separates the journal from the inner wall or bearing pads, and has a certain load-bearing capacity. Sliding bearings are further divided into liquid sliding bearings and gas sliding bearings depending on the medium used. Sliding bearings utilize the pressure of the medium between the bearing and the bearing pads to suspend the motor rotor in the air, so that there is no mechanical contact between the motor rotor and the motor stator, thus eliminating mechanical friction loss, resulting in a low-loss, high-performance motor. While achieving high rotor speed, this invention also boasts advantages such as no mechanical wear, low energy consumption, low noise, and long lifespan. The rotor speed is limited only by the tensile strength of the rotor material, allowing for very high circumferential speeds, making it increasingly widely used in high-speed equipment. To address the problems of high eddy current losses and excessively high temperatures in existing magnetic levitation motors, this invention incorporates the principle of sliding bearings to design a motor rotor, a magnetic levitation motor, and its installation method, as detailed below.

[0038] Please see Figures 1-14 , Figure 1 An embodiment of the present invention provides a motor rotor 1, comprising: a rotor 11 and a sliding sleeve 12. The sliding sleeve 12 is clearance-fitted with the rotor 11 to form a medium flow channel 13 between the inner side of the sliding sleeve 12 and the outer side of the rotor 11. The sliding sleeve 12 is provided with a medium inlet 1211 and a medium outlet 1221. Cooling medium enters the medium flow channel 13 through the medium inlet 1211 and flows out through the medium outlet 1221, so that the rotor 11 is suspended within the sliding sleeve 12.

[0039] Specifically, the sliding sleeve 12 is fitted over the outside of the rotor 11, covering the entire rotor 11. A certain gap is left between the sliding sleeve 12 and the rotor 11, so that a medium flow channel 13 for the cooling medium to flow can be formed between the inner side of the sliding sleeve 12 and the outer side of the rotor 11. The cooling medium can be liquid or gas, and is not limited here. The medium inlet 1211 is located at the top of the sliding sleeve 12, and the medium outlet 1221 is located at the bottom of the sliding sleeve 12. The cooling medium can enter from the medium inlet 1211, pass through the medium flow channel 13, and then flow out from the medium outlet 1221. During the flow of the medium, the cooling medium can flow from the top to the bottom of the rotor 11, fully contacting the rotor 11.

[0040] In this embodiment, the cooling medium flows as a fluid in the medium flow channel 13. The cooling medium carries away the heat of the rotor 11 and the heat generated by the stator core 21, ensuring that the permanent magnet 113 operates within a good temperature range. At the same time, the rotor 11 is suspended in the gap inside the sliding sleeve 12 as the fluid flows over its outer side. When the motor starts, the motor rotor 1 rotates at high speed. Under the action of gyroscopic effect, fluid viscosity, and fluid pressure, it will be stably suspended at the center of the axis of rotation. The entire rotor 11 rotates without mechanical contact with the sliding sleeve 12.

[0041] Reference Figure 2 In one embodiment, the rotor 11 includes an upper short shaft 111, a lower short shaft 112, a permanent magnet 113, and a sheath 114. The upper short shaft 111 and the lower short shaft 112 are located at opposite ends of the permanent magnet 113, and the upper short shaft 111, the lower short shaft 112, and the permanent magnet 113 are all interference-fitted with the sheath 114. Specifically, the rotor 11 has a three-shaft structure, with the three shafts of the rotor 11 consisting of the upper short shaft 111, the permanent magnet 113, and the lower short shaft 112 from top to bottom. During assembly, the permanent magnet 113, the upper short shaft 111, and the lower short shaft 112 are formed into a single unit by heat fitting. The sheath 114 is interference-fitted with the upper short shaft 111, the permanent magnet 113, and the lower short shaft 112, thereby fixing the three together into a single unit, which helps to improve the rigidity of the rotor 11 and improve the levitation accuracy and stability of the rotor 11.

[0042] Reference Figure 3In one embodiment, the sliding sleeve 12 includes an upper sliding sleeve 121 and a lower sliding sleeve 122. The upper sliding sleeve 121 is provided with the medium inlet 1211, and the lower sliding sleeve 122 is provided with the medium outlet 1221. The upper sliding sleeve 121 covers the upper short shaft 111 and part of the protective sleeve 114, and the lower sliding sleeve 122 covers the lower short shaft 112 and another part of the protective sleeve 114. The end face of the upper sliding sleeve 121 away from the medium inlet 1211 is in contact with the end face of the lower sliding sleeve 122 away from the medium outlet 1221. Specifically, the sliding sleeve 12 has a split structure, consisting of an upper sliding sleeve 121 and a lower sliding sleeve 122. The upper sliding sleeve 121 covers the upper half of the rotor 11, and the lower sliding sleeve 122 covers the lower half of the rotor 11. The two opposite end faces of the upper and lower sliding sleeves 122 are in contact to ensure that the upper and lower sliding sleeves 122 together cover the entire rotor 11. More specifically, the upper sliding sleeve 121 covers the entire upper short shaft 111 and the upper half of the permanent magnet 113, while the lower sliding sleeve 122 covers the entire lower short shaft 112 and the lower half of the permanent magnet 113. The medium inlet is located on the upper sliding sleeve 121, and the medium outlet 1221 is located on the lower sliding sleeve 122. The cooling medium flows into the medium flow channel 13 from the medium inlet on the upper sliding sleeve 121, passing sequentially through the upper short shaft 111, the permanent magnet 113, and the lower short shaft 112, and finally exits from the medium outlet 1221 of the lower sliding sleeve 122. This allows the cooling medium to pass through all parts of the rotor 11, fully contacting the rotor 11, carrying away the heat from the rotor 11, and improving the heat dissipation effect. Meanwhile, fluid flows inside the upper and lower sliding sleeves 122, so that the rotor 11 does not directly contact the sliding sleeves 12. The rotor 11 is suspended in the flow and rotates under the action of the electromagnetic force of the motor stator 2. There is no need to separately assemble sliding bearings at both ends of the rotor 11 shaft, which simplifies the structure of the rotor 11 and reduces the weight of the rotor 11.

[0043] Reference Figure 4 and Figure 5In one embodiment, both the upper short shaft 111 and the lower short shaft 112 include a front conical section, which is located at one end away from the permanent magnet 113. The upper sliding sleeve 121 is adapted to the shape of the upper short shaft 111, and the lower sliding sleeve 122 is adapted to the shape of the lower short shaft 112. Specifically, since the cooling medium generates resistance to the rotation of the rotor 11 when flowing through the medium channel 13, in order to reduce this resistance, this embodiment designs the upper short shaft 111 and lower short shaft 112 of the rotor 11 as a two-section shaft shroud structure. The upper short shaft 111 includes a first front conical section 1111 and a first rear cylindrical section 1112, and the lower short shaft 112 includes a second front conical section 1121 and a second rear cylindrical section 1122. The first rear cylindrical section 1112 is connected to one end of the permanent magnet 113, and the second rear cylindrical section 1122 is connected to the other end of the permanent magnet 113. The first front conical section 1111 and the second front conical section 1121 are the two end faces of the entire rotor 11. The cross-sections of the first front shaft section and the second front conical section 1121 are conical. Through this embodiment, designing the two ends of the rotor 11 as fluid shroud structures reduces the fluid pressure impact and pressure when the fluid flows through the end faces of the rotor 11 shaft, minimizing the vibration load and frontal resistance, while simultaneously meeting the requirement for the rotor 11 to suspend in the fluid.

[0044] In this embodiment, both the upper short shaft 111 and the lower short shaft 112 further include a rear cylindrical section. The two ends of the rear cylindrical section connect the front conical section and the permanent magnet 113. The diameter of the rear cylindrical section is equal to the diameter of the permanent magnet 113. The sheath 114 is interference-fitted with the rear cylindrical section and the permanent magnet 113. Specifically, to facilitate installation with the sheath 114 and ensure the integrity of the rotor 11, the diameter of the rear cylindrical section is designed to be equal to the diameter of the permanent magnet 113. Thus, when the sheath 114 is interference-fitted with the rotor 11, it can directly be interference-fitted with the permanent magnet 113 and the two rear cylindrical sections located at both ends of the permanent magnet 113. The front conical sections at both ends of the rotor 11 extend beyond the sheath 114. The maximum diameter of the front conical section, which is also the diameter of the end connecting to the rear cylindrical section, is slightly larger than the diameter of the rear cylindrical section, and the difference between the maximum diameter of the front conical section and the diameter of the rear cylindrical section is equal to the thickness of the sheath 114. Thus, when the sheath 114 is assembled, the maximum diameter of the front cone section is flush with the sheath 114, resulting in a smooth transition on the surface of the entire rotor 11 and good overall integrity. Furthermore, the internal shape of the sliding sleeve 12 is consistent with the external shape of the rotor 11. After assembly, the rotor 11 and the sliding sleeve 12 form a clearance fit. Fluid flows through the rotor 11, causing the rotor 11 to suspend within the sliding sleeve 12, thus solving the problem of mechanical friction between the rotor 11 and the sliding sleeve 12.

[0045] Continue to refer to Figure 4 and Figure 5Furthermore, the cone angle of the front cone section is 10°≤θ≤30°. The radius of the front cone section is r, and the diameter of the end of the front cone section connecting to the rear cylinder section is D, with a value of 0.3≤2r / D≤0.7. Specifically, the rotor 11 is designed with fluid shroud structures at both ends, the cone angle of the front cone sections at both ends is designed to be 10°≤θ≤30°, and the ratio of the radius r of the front cone section to the maximum diameter D is designed to be 0.3≤2r / D≤0.7. This reduces the fluid pressure impact and pressure when the fluid flows over the shaft end face of the rotor 11, minimizing the vibration load and frontal resistance, while simultaneously meeting the requirement for the rotor 11 to suspend in the fluid.

[0046] Reference Figure 6 and Figure 9 as well as Figure 11 In one embodiment, the medium inlet 1211 includes a hollow cylinder 1211a and a first through hole 1211b. The cylinder 1211a is located at the top end of the upper sliding sleeve 121, and the first through hole 1211b is opened at the top end of the upper sliding sleeve 121 and is located within the vertical projection plane of the cylinder 1211a. Specifically, since the medium inlet 1211 is the part where the cooling medium enters, it is necessary to ensure that the cooling medium flows in sufficiently without flowing out. Therefore, a cylinder 1211a is provided in the first front conical section 1111 to allow the cooling medium to flow in. Both ends of the cylinder 1211a are open. Cooling medium flows into one end of the cylinder 1211a, and the other end of the cylinder 1211a is connected to the top of the upper sliding sleeve 121. On the vertical projection surface of the cylinder 1211a, a plurality of first through holes 1211b are provided at the top of the upper sliding sleeve 121. The first through holes 1211b are jet holes. Cooling medium flows from the cylinder 1211a into the medium flow channel 13 through the jet holes and contacts the upper short shaft 111.

[0047] Reference Figure 5 , Figure 7 , Figure 10 as well as Figure 12 In this embodiment, the lower short shaft 112 has a tool holder mounting port 1123 on its front conical section, and the medium outlet 1221 is located around the tool holder mounting port 1123 at the bottom end of the lower sliding sleeve 122. Specifically, the rotor 11 also includes a tool holder 115, on which the tool holder mounting port 1123 is provided, and the tool holder 115 is mounted. The medium outlet 1221 is also a jet hole, located at the bottom end of the lower sliding sleeve 122, and is located around the tool holder mounting port 1123, meaning the diameter of the jet hole is slightly larger than that of the tool holder mounting port 1123. Thus, the cooling medium can flow out along the tool holder 115.

[0048] In this embodiment, the upper and lower sliding sleeves 122 are provided with a medium inlet 1211 and an outlet jet hole at both ends. The fluid flows through the rotor 11 to cool the rotor 11 and the external stator components, solving the problems of poor heat dissipation of the rotor 11 and stator components, high temperature and demagnetization of the permanent magnet 113, and improving the service life of the whole machine.

[0049] Reference Figures 6-10 In one embodiment, the upper sliding sleeve 121 has a first limiting portion 1212 protruding from its side wall, and the lower sliding sleeve 122 has a second limiting portion 1222 protruding from its side wall. The first limiting portion 1212 and the second limiting portion 1222 are used to fix themselves to the end faces of the shaft holes 23 at both ends of the stator core 21. Specifically, since the rotor 11 and the sliding sleeve 12 have no mechanical contact, and the rotor 11 is suspended inside the sliding sleeve 12, a corresponding limiting structure needs to be provided on the sliding sleeve 12 for fixation, specifically, fixation to the stator. (Refer to...) Figure 13 More specifically, the motor stator 2 includes a stator core 21 and a stator winding 22. The stator winding 22 is wound on the stator core 21. The stator core 21 is provided with a shaft hole 23 for the rotor 11 to rotate. Both ends of the shaft hole 23 have end faces. The limiting structure on the sliding sleeve 12 includes a first limiting part 1212 provided on the upper sliding sleeve 121 and a second limiting part 1222 provided on the lower sliding sleeve 122. During installation, the first limiting part 1212 of the upper sliding sleeve 121 engages with the end face of one end of the shaft hole 23 for limiting, and the second limiting part 1222 of the lower sliding sleeve engages with the end face of the other end of the shaft hole 23 for limiting, thus realizing the assembly of the sliding sleeve 12. It should be noted that the first limiting part 1212 and the second limiting part 1222 can have various structural forms, such as an outer flange provided on the side wall of the upper and lower sliding sleeves 122. Of course, it can be understood that other structures are also possible, which are not limited here.

[0050] Reference Figure 13 and Figure 14 This invention also provides a magnetic levitation motor, including a motor rotor 1 and a motor stator 2. The motor rotor 1 is the same as the motor rotor 1 described in the above embodiments, and the motor rotor 1 is rotatably disposed in the motor stator 2. It should be noted that the motor rotor 1 has been described in detail in the above embodiments, and for the sake of brevity, it will not be described again here.

[0051] In this embodiment, the rotor 11 is simplified to a three-section shaft with an elliptical cross-section and a fairing-shaped end. Utilizing the heat-shrinkable surface-mounted rotor 11 structure of the sheath 114, the functions of the motor rotor 1 and the air bearing are integrated, resulting in a simple structure with diverse functions. Fluid flowing over the outside of the rotor 11 can suspend it in the air. When the motor starts, the rotor 1 rotates at high speed, and under the influence of gyroscopic effect and fluid pressure, it remains stably suspended at the center of the rotation axis. The sliding sleeve 12 is designed with fluid inlet and outlet. Pressure forces the fluid to flow, and as the fluid flows over the rotor 11, it carries away the heat from the rotor 11. Simultaneously, the fluid flows through the outlet 1221 to the outside of the sliding sleeve 12, cooling the stator core 2 and stator windings 22, ensuring the motor operates within a suitable temperature range.

[0052] Reference Figure 15 The present invention also provides a method for installing a levitation motor, the method comprising steps S1-S3.

[0053] S1. The upper short shaft 111, permanent magnet 113, and lower short shaft 112 are spliced ​​together with the sheath 114 by interference fit to form a whole to form the motor rotor 1.

[0054] S2. Fix the sliding sleeve 122 to one end of the shaft hole 23 of the stator core 21, and install the motor rotor 1 into the shaft hole 23.

[0055] S3. Fix the upper sliding sleeve 121 to the other end of the shaft hole 23 of the stator core 21 so that the motor rotor 1 is fitted together with the upper sliding sleeve 121.

[0056] Specifically, firstly, the upper short shaft 111, permanent magnet 113, and lower short shaft 112 are spliced ​​together into a whole by the sheath 114 to form the motor rotor 1; then, after the silicon steel sheets are stacked, the enameled wire windings are embedded to form the motor stator 2; next, the lower sliding sleeve 122 is fixed in the stator core 21 of the motor stator 2, and then the motor rotor 1 is installed; finally, the upper sliding sleeve 121 is installed and fixed in the stator core 21 of the motor stator 2.

[0057] In this embodiment, the rotor 11 shaft and the sliding bearing rotor 11 are designed as an integrated structure (it is both the motor rotor 1 and the sliding bearing rotor 11). After the permanent magnet 113 is assembled, the permanent magnet 113, the upper short shaft 111, and the lower short shaft 112 are integrated into a whole by heat fitting through the sleeve 114. At the same time, the rotor 11 has a shape that conforms to the design of suspension in fluid, and the end adopts the shape of a fluid shroud, which forms a clearance fit with the outer sliding sleeve 12. This clearance forms a medium fluid flow channel. Pressurized fluid flows into the clearance from the medium inlet 1211 of the sliding sleeve 12, so that the rotor 11 has no mechanical contact with the sliding sleeve 12, thereby suspending the rotor 11 within the sliding sleeve 12. The sliding sleeve 12 (upper sliding sleeve 121, lower sliding sleeve 112) 22) Fixed on the iron core of the motor stator 2, the fluid in the sliding sleeve 12 flows under pressure, enters from the medium inlet 1211, flows in the gap between the rotor 11 and the sliding sleeve 12, and then flows out through the medium outlet 1221. The fluid medium will carry away the heat of the rotor 11 and the heat generated by the iron core of the motor stator 2 inside the sliding sleeve 12, ensuring that the permanent magnet 113 works within a good temperature range. At the same time, the motor rotor 1 can be suspended in the gap inside the sliding sleeve 12 by the fluid flowing outside the rotor 11. When the motor starts, the motor rotor 1 rotates at high speed. Under the action of gyroscopic effect, fluid viscosity, and fluid pressure, it will be stably suspended at the center position of the axis of rotation. The entire rotor 11 rotates without mechanical contact with the sliding sleeve 12.

[0058] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any person skilled in the art can easily conceive of various equivalent modifications or substitutions within the technical scope disclosed in the present invention, and these modifications or substitutions should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. An electric machine rotor, characterized in that, It includes a rotor and a sliding sleeve. The sliding sleeve is clearance-fitted with the rotor to form a medium flow channel between the inner side of the sliding sleeve and the outer side of the rotor. The sliding sleeve is provided with a medium inlet and a medium outlet. Cooling medium enters the medium flow channel through the medium inlet and flows out from the medium outlet to suspend the rotor inside the sliding sleeve. The rotor includes an upper short shaft, a lower short shaft, a permanent magnet, and a sheath. The upper short shaft and the lower short shaft are located at both ends of the permanent magnet, and the upper short shaft, the lower short shaft, and the permanent magnet are all interference-fitted with the sheath. The sliding sleeve includes an upper sliding sleeve and a lower sliding sleeve. The upper sliding sleeve is provided with the medium inlet, and the lower sliding sleeve is provided with the medium outlet. The upper sliding sleeve covers the upper short shaft and part of the protective sleeve, and the lower sliding sleeve covers the lower short shaft and another part of the protective sleeve. The end face of the upper sliding sleeve away from the medium inlet is in contact with the end face of the lower sliding sleeve away from the medium outlet.

2. The electric machine rotor of claim 1, wherein, Both the upper short shaft and the lower short shaft include a front conical section, which is located at the end away from the permanent magnet. The upper sliding sleeve is adapted to the shape of the upper short shaft, and the lower sliding sleeve is adapted to the shape of the lower short shaft.

3. The motor rotor of claim 2, wherein, Both the upper short shaft and the lower short shaft further include a rear cylindrical section. The two ends of the rear cylindrical section connect the front conical section and the permanent magnet. The diameter of the rear cylindrical section is equal to the diameter of the permanent magnet. The sheath is interference-fitted with the rear cylindrical section and the permanent magnet.

4. The motor rotor of claim 2, wherein, The medium inlet includes a hollow cylinder and a first through hole. The cylinder is located at the top of the upper sliding sleeve, and the first through hole is opened at the top of the upper sliding sleeve and is located in the vertical projection plane of the cylinder.

5. The motor rotor according to claim 2, characterized in that, The front tapered section of the lower short shaft is provided with a tool holder mounting port, and the medium outlet is opened at the bottom end of the lower sleeve around the tool holder mounting port.

6. The motor rotor according to claim 2, characterized in that, The cone angle of the front cone section is 10°≤θ≤30°.

7. The motor rotor according to claim 3, characterized in that, The radius of the front conical section is r, and the diameter of the end of the front conical section that connects to the rear cylindrical section is D, where 0.3≤2r / D≤0.

7.

8. The motor rotor according to any one of claims 1-7, characterized in that, The upper sliding sleeve has a first limiting part protruding from its side wall, and the lower sliding sleeve has a second limiting part protruding from its side wall. The first limiting part and the second limiting part are used to be fixed on the end faces of the two ends of the shaft hole of the stator core.

9. A magnetic levitation motor, characterized in that, It includes a motor rotor and a motor stator, wherein the motor rotor is the motor rotor according to any one of claims 1-8, and the motor rotor is rotatably disposed in the motor stator.

10. A method for installing a magnetic levitation motor, characterized in that, The method, applied to the magnetic levitation motor of claim 9, comprises: The upper short shaft, permanent magnet, lower short shaft and sheath are interference-fitted together to form a whole to form the motor rotor; The sliding sleeve is fixed to one end of the shaft hole of the stator core, and the motor rotor is installed into the shaft hole; The upper sliding sleeve is fixed on the other end of the shaft hole of the stator core so that it, together with the upper sliding sleeve, can fit the motor rotor.

Images