A magnetic bearing structure for a composite material shaft and an assembly method thereof

Abstract

The present invention discloses a magnetic bearing structure for a composite material shaft and an assembly method thereof. The magnetic bearing structure includes a sleeve assembly, a magnetic bearing base assembly, and a base sleeve assembly. The sleeve and its parts are fixed on the composite material shaft and rotate with the shaft; the magnetic bearing base and its parts, the base sleeve and its parts are fixed at the position where the bearing structure needs to be installed. During normal operation, the radial magnetic bearing on the base generates an electromagnetic force acting on the rotor ring in the sleeve, thereby supporting the sleeve and the composite material shaft. At the same time, the two groups of axial magnetic bearings on the base and the base sleeve and the different orientations of the permanent magnetic ring on the sleeve form magnetic forces in different directions to control the sleeve from axial deviation. Ensure that the radial magnetic bearing can work in a normal position. The present invention successfully realizes the successful application of magnetic bearings to composite material shafts.

Description

Technical Field

[0001] The invention relates to a magnetic suspension bearing, in particular to a magnetic bearing structure for a composite material shaft and an assembly method thereof. Background Art

[0002] As a transmission element widely used in mechanical structures, composite drive shafts have the advantages of light weight, high transmission power and simple maintenance. They are currently widely used in the fields of ships, vehicles and aerospace. Magnetic bearings have the characteristics of no mechanical friction, no need for lubrication, high critical speed, long service life and high reliability. Due to the light weight of the composite shaft itself, the use of composite materials to make shafts requires very high control accuracy, and magnetic bearings can meet this requirement. At the same time, when composite materials are used as the material of the shaft, it is necessary to reduce the friction between the shaft and the bearing to avoid the shaft fiber being worn off and failing. Magnetic bearings are non-contact bearings, which can well avoid contact between the bearing and the shaft. However, since the composite shaft itself is not magnetic, traditional magnetic bearings are difficult to apply to composite shafts because they cannot attract composite shafts. If magnetic bearings are applied to composite drive shafts, it is of great significance for the streamlined design and engineering application of composite transmission systems.

[0003] Patented composite material transmission shaft and sliding bearing thereof (CN 113790206 A) designs a composite material transmission shaft and sliding bearing thereof to realize the supporting function of the composite material shaft, but the bearing form is still a contact bearing, and the energy loss caused by friction during the transmission process is very large.

[0004] The paper titled "Design and Research of Marine Composite Shafting System" published by Yin Zhiyao et al. in "Fiber Composite Materials" shows a support arrangement of composite shafting system. The method is to connect a short steel shaft in the middle of two sections of composite shafts and arrange bearings on the steel shaft. This method successfully solves the support problem of composite shafts and also provides a new idea for the application of magnetic bearings in shafting systems containing composite shafts. However, the use of couplings to connect multiple sections of shafts is prone to misalignment and vibration of the shafting system.

[0005] An article titled "Advances in Advanced Composite Intermediate Shafts" in the Ship Design Newsletter mentioned that because the average surface pressure of conventional forged steel shafts is much greater than that of fiber-reinforced plastic shafts, non-lubricated bearings may be used, and the fiber-reinforced plastic shaft surface may be treated by metal spraying and polishing to apply conventional metal non-lubricated bearings. However, when metal spraying is used, cracks will be generated on the treated surface, and polishing will cause wear on the shaft surface and wear out the fiber filaments.

[0006] The patent for a magnetic suspension bearing system and its control method (CN 115217848 A) uses a rotor wrapped around the outside of the shaft and then applies a magnetic bearing to successfully achieve magnetic suspension of the motor shaft. At the same time, it provides a new idea for the application of magnetic bearings on composite shafts: adding a magnetic rotor to the outside of the shaft to achieve magnetic suspension of the composite shaft. However, the rotor diameter will increase, resulting in an increase in the volume of the magnetic bearing.

[0007] Patent A permanent magnet biased magnetic bearing (CN 115681329 A) designs a permanent magnet biased magnetic bearing, whose structure sets the excitation coil and the permanent magnet in different positions, avoiding the disadvantage of the bias magnetic flux and the control magnetic flux of the traditional permanent magnet biased magnetic bearing crossing each other. However, the structure adopted belongs to the traditional thrust plate plus the magnetic suction device on both sides, and the bias bearing is separated from the radial bearing, which increases the volume of the magnetic bearing. Summary of the invention

[0008] Purpose of the invention: In view of the above problems, the purpose of the present invention is to provide a magnetic bearing structure for a composite material shaft, so as to realize the use of the magnetic bearing on the composite material shaft, and to provide an assembly method thereof.

[0009] Technical solution: A magnetic bearing structure for a composite material shaft, including a sleeve assembly, a magnetic bearing base assembly, and a base sleeve assembly. The sleeve assembly includes a sleeve body, an inner permanent magnet ring, a rotor ring, and an outer permanent magnet ring. The inner permanent magnet ring is embedded in the inner bottom surface of the sleeve body, the rotor ring is embedded in the inner circumferential surface of the sleeve body, and the outer permanent magnet ring is embedded in one end surface of the sleeve body. The magnetic bearing base assembly includes a magnetic bearing base body, a radial electromagnetic part, an outer axial electromagnetic part, and a sensor. The base sleeve assembly includes a base sleeve body, an inner axial electromagnetic part, and a sensor. The base sleeve body is placed in the sleeve body. A plurality of inner axial electromagnetic components are embedded at intervals along the circumferential direction on one side surface of the sleeve body and are respectively aligned with the inner permanent magnet ring; the magnetic bearing base body is penetrated in the base sleeve body; a plurality of radial electromagnetic components are disposed at intervals along the circumferential direction of the magnetic bearing base body and are respectively penetrated in the magnetic bearing base body and the base sleeve body in sequence; the radial electromagnetic components cooperate with the rotor ring; a plurality of outer axial electromagnetic components are embedded at intervals along the circumferential direction on one side surface of the magnetic bearing base body and are respectively aligned with the outer permanent magnet ring; at least one sensor 1 is installed on the magnetic bearing base body, and at least one sensor 2 is installed on the base sleeve body.

[0010] Furthermore, an annular inner permanent magnet ring groove is provided on the inner bottom surface of the sleeve body, and the inner permanent magnet ring is installed in the inner permanent magnet ring groove. A circle of rotor ring groove is provided on the inner circumferential surface of the sleeve body, and the rotor ring is installed in the rotor ring groove. An annular outer permanent magnet ring groove is provided on the end surface of the sleeve body opposite to the magnetic bearing base body, and the outer permanent magnet ring is installed in the outer permanent magnet ring groove. A plurality of heat dissipation holes are also spaced apart on the outer circumferential surface of the sleeve body.

[0011] When the magnetic bearing is working, a large amount of heat will be generated. Therefore, in order to dissipate the heat, a circle of heat dissipation holes is set on the sleeve body.

[0012] The sleeve body needs to be processed as an integral part, that is, an integrated structure, in order to reduce the impact of the asymmetric structure on the dynamic balance of the shaft system.

[0013] Furthermore, the radial electromagnetic component includes a radial magnetic bearing core and a radial magnetic bearing coil. The radial magnetic bearing core is a cylindrical structure. The radial magnetic bearing coil is wound on the outer circumferential surface of the radial magnetic bearing core. The radial magnetic bearing core is sequentially inserted into the magnetic bearing base body and the base sleeve body, so that the radial magnetic bearing coil is located in the base sleeve body, and one end of the radial magnetic bearing core is opposite to the rotor ring.

[0014] Optimally, the outer axial electromagnetic component includes an outer axial magnetic bearing core and an outer axial magnetic bearing coil. The outer axial magnetic bearing core is a rectangular structure with the outer axial magnetic bearing coil wound around it. The outer axial magnetic bearing core is embedded in the magnetic bearing base body, and one of the non-winding surfaces of the outer axial magnetic bearing core is opposite to the outer permanent magnet ring.

[0015] Preferably, the outer axial magnetic bearing coils are wound in the same direction as the radial magnetic bearing coils.

[0016] Furthermore, a plurality of base sensor placement holes are circumferentially spaced apart on one side surface of the magnetic bearing base body where the outer axial electromagnetic component is installed, and sensor 1 is installed in the base sensor placement hole.

[0017] Furthermore, the inner axial electromagnetic component includes an inner axial magnetic bearing core and an inner axial magnetic bearing coil. The inner axial magnetic bearing core is a rectangular structure with the inner axial magnetic bearing coil wound around it. The inner axial magnetic bearing core is embedded in one end face of the base sleeve body, and one of the non-winding surfaces of the inner axial magnetic bearing core is opposite to the inner permanent magnet ring.

[0018] Furthermore, a plurality of sleeve sensor placement holes are provided on the outer peripheral surface of the base sleeve body at intervals in the circumferential direction, and the sensor 2 is installed in the sleeve sensor placement hole.

[0019] Furthermore, the magnetic pole directions of the inner permanent magnetic ring and the outer permanent magnetic ring are opposite.

[0020] A method for assembling the magnetic bearing structure for a composite shaft as described above comprises the following steps:

[0021] S1: Determine the position to be installed, and fix one half of the magnetic bearing base body to the position to be installed;

[0022] S2: fix the inner permanent magnet ring, the rotor ring and the outer permanent magnet ring on the sleeve body respectively;

[0023] S3: Sleeve the shaft sleeve body on the composite material shaft, and then sleeve the base sleeve body on the composite material shaft, so that the base sleeve body and the recessed part of the shaft sleeve body are spaced and opposite to each other;

[0024] S4: The composite material shaft is supported as a whole near the position to be installed by a temporary support body, and the other half of the magnetic bearing base body is sleeved on the composite material shaft, and the two halves of the magnetic bearing base body are connected to form a complete magnetic bearing base body, so that the magnetic bearing base body and the composite material shaft are spaced and coaxially aligned;

[0025] S5: Fix the outer axial electromagnetic component on the magnetic bearing base body and install sensor 1;

[0026] S6: Install the second sensor on the base sleeve body;

[0027] S7: Move the base sleeve body axially so that it is sleeved on the magnetic bearing base body, and the groove on the top of the base sleeve body should be aligned with the tooth-shaped front end recessed part of the magnetic bearing base body. At the same time, align the holes on the side wall of the base sleeve body with the holes on the side wall of the magnetic bearing base body. Pass the wiring of sensor 1 and sensor 2 through the small hole at the bottom of the magnetic bearing base body and lead it out close to its inner wall. Use bolts to fix the base sleeve body on the magnetic bearing base body so that the magnetic bearing base body is completely fixed.

[0028] S8: Install the inner axial electromagnetic component on the base sleeve body;

[0029] S9: Install the radial electromagnetic component, pass the radial electromagnetic component through the base sleeve body and the magnetic bearing base body in sequence, and connect them with the magnetic bearing base body through threads;

[0030] S10: After all parts are installed, the sleeve body is moved axially to be sleeved on the base sleeve body. After it is in place, the sleeve body is fixed to the composite shaft by axial positioning bolts. After power is turned on to ensure that the bearing structure can work normally, the temporary support body of S4 is removed.

[0031] Beneficial effects: Compared with the prior art, the advantages of the present invention are:

[0032] (1) An outer rotor magnetic bearing structure is designed, and a steel rotor ring is set on the sleeve body. During operation, the magnetic bearing supports the rotor ring, thereby driving the composite shaft to suspend, successfully solving the problem of supporting the composite shaft with magnetic bearings.

[0033] (2) The outer rotor magnetic bearing is adopted, and the working area of ​​the bearing is placed around the shaft, rather than on the shaft body. The contact area is only a small part of the front end of the sleeve, which only needs to withstand static friction to drive the sleeve to rotate, and does not withstand heat. Therefore, the present invention avoids the problem that the composite shaft body itself cannot withstand the friction and heat brought by traditional bearings.

[0034] (3) A magnetic bearing is used to support the composite shaft. The magnetic bearing is a non-contact bearing that does not dissipate energy due to friction and can improve transmission efficiency.

[0035] (4) The shaft sleeve assembly of the present invention can be fixed on the shaft body, and its working area is not on the surface of the shaft body. The surface of the shaft body does not bear any load except the static friction load of the fixed shaft sleeve. It can be applied to a single-piece (non-segmented) composite material shaft, which can reduce the vibration caused by the misalignment caused by the use of couplings.

[0036] (5) The composite shaft is supported by magnetic levitation and does not use non-traditional lubricated bearings, so there will be no problems such as cracks or fiber breakage caused by painting or polishing.

[0037] (6) It is an outer rotor bearing, with the stator inside and the rotor ring outside, and the rotor ring diameter will not be increased due to the structure wrapped outside the rotor ring, thereby causing the volume of the magnetic bearing to increase. In addition, the present invention also adopts a method of combining radial electromagnetic components with two axial electromagnetic components to further reduce the design volume of the magnetic bearing.

[0038] (7) Heat dissipation holes are designed on the sleeve body, which has the advantage of timely heat dissipation.

[0039] (8) The shaft sleeve body is fixed by an axial positioning and fixing method, so that the shaft sleeve body can be fixed on the shaft without damaging the shaft body. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a schematic diagram of the assembly structure of the present invention;

[0041] Figure 2 is an exploded view of the present invention;

[0042] Figure 3 It is a schematic diagram of the structure of the shaft sleeve assembly;

[0043] Figure 4 It is a three-dimensional structural schematic diagram of the sleeve body;

[0044] Figure 5 is a schematic diagram of the structure of a magnetic bearing base assembly;

[0045] Figure 6 is a schematic diagram of the three-dimensional structure of the magnetic bearing base assembly;

[0046] Figure 7 is a schematic diagram of the structure of a magnetic bearing base sleeve assembly;

[0047] Figure 8 It is a three-dimensional structural schematic diagram of a magnetic bearing base sleeve assembly;

[0048] Fig. 9 It is a schematic diagram of the axial electromagnetic force on the sleeve body;

[0049] Fig.10 is a schematic diagram of the magnetic circuit of the outer axial electromagnetic component in one embodiment;

[0050] Fig.11 is a schematic diagram of the magnetic circuit of the inner axial electromagnetic component in one embodiment;

[0051] Fig.12 FIG. 1 is a schematic diagram of a magnetic circuit of a radial electromagnetic component in an embodiment. DETAILED DESCRIPTION

[0052] The present invention will be further described below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and are not used to limit the scope of the present invention.

[0053] A magnetic bearing structure for a composite shaft, such as Figures 1 to 12 As shown, it includes a shaft sleeve assembly 3, a magnetic bearing base assembly 4, and a base sleeve assembly 5.

[0054] The sleeve assembly 3 includes a sleeve body 300, an inner permanent magnet ring 301, a rotor ring 302, and an outer permanent magnet ring 303. The magnetic bearing base assembly 4 includes a magnetic bearing base body 400, a radial electromagnetic component, an outer axial electromagnetic component, and a sensor 1. The base sleeve assembly 5 includes a base sleeve body 500, an inner axial electromagnetic component, and a sensor 2. The directions of the magnetic flux lines of the outer axial electromagnetic component and the inner axial electromagnetic component are consistent.

[0055] An annular inner permanent magnet ring groove 304 is provided on the inner bottom surface of the sleeve body 300, and the inner permanent magnet ring 301 is installed in the inner permanent magnet ring groove 304. The inner permanent magnet ring groove 304 has a smaller diameter and a rectangular cross-sectional shape. The inner permanent magnet ring 301 has a rectangular cross-section. The relevant parameters of the two need to match, and the inner permanent magnet ring 301 can be fixed in the inner permanent magnet ring groove 304 by screws; a circle of rotor ring groove 305 is provided on the inner circumferential surface of the sleeve body 300, and the rotor ring 302 is installed in the rotor ring groove 305. The cross-sectional shape of the rotor ring groove 305 is rectangular, and the cross-sectional shape of the rotor ring 302 is rectangular. The relevant parameters of the two need to match, and the rotor ring 302 can be fixed in the groove by screws. An annular outer permanent magnet ring groove 306 is provided on the end surface of the shaft sleeve body 300 opposite to the magnetic bearing base body 400, and the outer permanent magnet ring 303 is installed in the outer permanent magnet ring groove 306. The outer permanent magnet ring groove 306 has a larger diameter and a rectangular cross-section. The outer permanent magnet ring 303 has a rectangular cross-section. The relevant parameters of the two need to match. The outer permanent magnet ring 303 can be fixed in the outer permanent magnet ring groove 306 by screws; the inner permanent magnet ring 301 and the outer permanent magnet ring 303 have opposite magnetic pole directions, that is, different magnetic poles should be pointed in the same direction during installation. For example, when the S pole of the inner permanent magnet ring 301 points to the outside of the shaft sleeve, the outer permanent magnet ring 303 should point the N pole to the outside of the shaft sleeve. A plurality of heat dissipation holes 307 are also spaced apart on the outer peripheral surface of the shaft sleeve body 300.

[0056] The base sleeve body 500 is placed inside the sleeve body 300, and multiple inner axial electromagnetic parts are embedded on one side surface of the sleeve body 500 at circumferential intervals and are respectively aligned with the inner permanent magnet ring 301. The inner axial electromagnetic parts include an inner axial magnetic bearing core 501 and an inner axial magnetic bearing coil 502. The inner axial magnetic bearing core 501 is a rectangular structure with the inner axial magnetic bearing coil 502 wound around it. The inner axial magnetic bearing core 501 is embedded on one end surface of the base sleeve body 500, and one of the non-winding surfaces of the inner axial magnetic bearing core 501 is opposite to the inner permanent magnet ring 301.

[0057] The magnetic bearing base body 400 is inserted into the base sleeve body 500, and a plurality of radial electromagnetic components are arranged at intervals along the circumference of the magnetic bearing base body 400 and are respectively and sequentially inserted into the magnetic bearing base body 400 and the base sleeve body 500. The radial electromagnetic components cooperate with the rotor ring 302. The radial electromagnetic components include a radial magnetic bearing core 401 and a radial magnetic bearing coil 402. The radial magnetic bearing core 401 is a cylindrical structure. The radial magnetic bearing coil 402 is wound on the outer circumferential surface of the radial magnetic bearing core 401. The radial magnetic bearing core 401 is sequentially inserted into the magnetic bearing base body 400 and the base sleeve body 500, so that the radial magnetic bearing coil 402 is located in the base sleeve body 500, and one end of the radial magnetic bearing core 401 is opposite to the rotor ring 302. The structural arrangement of the plurality of radial electromagnetic components and the rotor ring 302 meets the basic requirements of the magnetic suspension bearing and can realize the basic functions of the magnetic suspension bearing.

[0058] like Figure 6 As shown, the magnetic bearing base body 400 is divided into two halves with the same structure that are butt-jointed to form a body composed of end faces of cylindrical structures with two outer diameters, and one of the halves can be appropriately extended to meet the needs of the installation environment. A hole for installing the radial magnetic bearing core 401 and its encapsulated coil 402 is provided on the magnetic bearing base body 400. The hole is located on the outer peripheral surface of the small diameter cylindrical structure of the magnetic bearing base body 400 and extends and penetrates radially. A threaded portion is provided in the lower half of the hole, and correspondingly, a thread is also provided on the radial magnetic bearing core 401. After the radial magnetic bearing coil 402 is wound on the radial magnetic bearing core 401, it is fixed to the magnetic bearing base by threads, and the lead wire is led out through the hole at the bottom of the hole to the outside of the bearing for wiring.

[0059] Multiple outer axial electromagnetic parts are embedded in one side surface of the magnetic bearing base body 400 at circumferential intervals and are respectively aligned with the outer permanent magnet ring 303. The outer axial electromagnetic parts include an outer axial magnetic bearing core 403 and an outer axial magnetic bearing coil 404. The outer axial magnetic bearing core 403 is a rectangular structure with the outer axial magnetic bearing coil 404 wound around it. The outer axial magnetic bearing core 403 is embedded in the magnetic bearing base body 400, and one of the non-winding surfaces of the outer axial magnetic bearing core 403 is opposite to the outer permanent magnet ring 303.

[0060] Grooves for installing the outer axial magnetic bearing core 403 and the outer axial magnetic bearing coil 404 are provided on the outer peripheral surface of the large-diameter cylindrical structure of the magnetic bearing base body 400. After the outer axial magnetic bearing coil 404 is wound on the core, the outer axial electromagnetic component is fixed to the magnetic bearing base body 400 by screws.

[0061] After all radial electromagnetic components and the outer axial electromagnetic components are installed, the two halves of the magnetic bearing base body 400 are connected together and fixed by bolts and base sleeves.

[0062] At least one sensor 1 is installed on the magnetic bearing base body 400, and at least one sensor 2 is installed on the base sleeve body 500. The magnetic bearing base body 400 is also provided with a plurality of base sensor placement holes 405 spaced apart along the circumferential direction on one side surface where the outer axial electromagnetic component is installed, and the sensor 1 is installed in the base sensor placement hole 405. A plurality of sleeve sensor placement holes 503 are spaced apart along the circumferential direction on the outer circumferential surface of the base sleeve body 500, and the sensor 2 is installed in the sleeve sensor placement hole 503.

[0063] After installation, there is a working air gap -6 between the radial magnetic bearing core 401 and the rotor ring 302, and there are also working air gaps between the outer axial magnetic bearing core 403 and the outer permanent magnet ring 303, and between the inner axial magnetic bearing core 501 and the inner permanent magnet ring 301.

[0064] The existing composite material shaft supports and magnetic bearings have the following technical problems (1) to (6), which are solved by the present invention:

[0065] (1) The composite shaft itself is not magnetic. When the magnetic bearing is applied to the composite shaft, a part of the magnetic structure needs to be added separately in the structural design to be attracted by the magnetic bearing. (2) The load borne by the contact surface between the composite shaft and the bearing is large and of many types. There are loads such as thermal load and periodic load on the contact surface between the bearing and the shaft. (3) The bearing is a contact bearing, which has large energy loss and reduced transmission efficiency. (4) Composite shafts are mostly in the form of multi-section shafts, which increase the application of couplings and cause shaft vibration problems due to misalignment. (5) In order to apply traditional non-lubricated bearings, composite shafts will be painted and polished, but painting will cause cracks in the shaft and polishing will break the fiber filaments. (6) In the current design process of magnetic bearings, the magnetic structure will be coated on the outside of the rotor before applying the magnetic bearing, or the offset bearing will be separated from the radial support bearing. These will cause the final volume of the magnetic bearing to become larger, and there will be limitations in some places where volume and quality are required.

[0066] In addition to the above-mentioned technical problems, there are some other issues that should be paid attention to during design:

[0067] (1) Due to the compact internal structure of traditional bearings, it is difficult to detect the relevant parameters of the internal system using conventional sensors, so they can only be detected by external means. Active magnetic bearings can detect certain states of the rotor-bearing system in real time. Therefore, attention should be paid to the layout of sensors during design. (2) Active magnetic bearings generate a lot of heat when working. When designing active magnetic bearings, heat dissipation should also be considered. (3) When installing accessories on composite shafts, care should be taken to avoid damage to the shaft as much as possible to ensure the integrity of the shaft itself.

[0068] The inner permanent magnet ring 301 and the outer permanent magnet ring 303 installed inside the sleeve body 300 have different magnetic pole directions, that is, the directions of the magnetic flux lines along the axial direction are opposite. This is to ensure that after the magnetic bearing is energized, when the electromagnetic force generated is applied to the sleeve body 300, it will be two electromagnetic forces in different directions. The two electromagnetic forces will balance the force exerted on the sleeve body 300, such as Fig. 9 As shown, F1 and F2 are in opposite directions. Fig.10 As shown in FIG. 1 , according to the direction of the magnetic flux lines in the figure, it is easy to see that an attractive force is generated inside the sleeve body 300; at the same time, the outer permanent magnet ring 303 should point the N pole to the outside of the sleeve body 300, as shown in FIG. Fig.11 As shown, it is easy to see that the outer side of the sleeve body 300 generates a repulsive force to ensure that the radial electromagnetic components can be consistently in an effective working position, ensuring the effectiveness and working stability of the magnetic suspension.

[0069] When the N pole of the inner permanent magnet ring 301 points to the inner axial magnetic bearing installed on the base sleeve body 500, the corresponding S pole of the outer permanent magnet ring 303 should point to the outer axial magnetic bearing installed on the magnetic bearing base body 400; at the same time, in order to reduce the workload of the installers and ensure that the electromagnetic forces on the inner and outer sides of the magnetic bearing can be balanced, the outer axial magnetic bearing coil 404, the radial magnetic bearing coil 402, and the inner axial magnetic bearing coil 502 can be wound in the same direction when wound on the iron core.

[0070] In addition, in one embodiment, the radial magnetic bearing coil 402 can also be arranged in two alternating winding directions, such as Fig.12 As shown, the number of radial electromagnetic parts is 8, 4 radial magnetic bearing coils 402 are wound on the radial magnetic bearing core 401 in a clockwise direction, and 4 are wound on the radial magnetic bearing core 401 in a counterclockwise direction. When installing, the magnetic bearings of the two winding directions should be installed alternately. After power is turned on, the magnetic circuit is as follows Fig.12 shown.

[0071] A sensor placement hole 405 is added to the magnetic bearing base body 400, and a sensor placement hole 503 is added to the base sleeve 500. Sensor 1 and sensor 2 can be displacement sensors. Sensor 1 in the placement hole 405 mainly detects axial signals, and sensor 2 in the placement hole 503 mainly detects radial signals. When axial displacement of the sleeve body 300 is detected, the signal will be transmitted to the processing center, and then the current in the coil will be changed, thereby changing the force on the sleeve body 300 and re-controlling the sleeve body 300 to the normal working position.

[0072] Since the magnetic bearing base body 400 is divided into two halves, an ear-shaped portion is provided next to the disk-shaped portion of the magnetic bearing base body 400 in order to fix the magnetic bearing base body 400, and the upper and lower parts of the magnetic bearing base body 400 are connected by bolts. However, there is no fixing device inside the magnetic bearing base body 400, so a base sleeve 500 is provided, which is sleeved on the axial protrusion of the magnetic bearing base body 400 for constraint and fixation. The final radial magnetic bearing installation diagram should be as shown below: Figure 8 shown.

[0073] The above-mentioned assembly method of the magnetic bearing structure for the composite shaft includes the following steps. It should be noted that the order of the steps cannot be replaced without specific instructions:

[0074] S1: After selecting a specific location where the present invention needs to be installed, fix one half of the magnetic bearing base body 400 there;

[0075] S2: Install the inner permanent magnet ring 301, the rotor ring 302, and the outer permanent magnet ring 303 in the sleeve body 300 and fix them with screws. When installing, it should be noted that the magnetic flux lines of the inner permanent magnet ring 301 and the outer permanent magnet ring 303 are in opposite directions along the axial direction;

[0076] S3: First, insert the sleeve body 300 onto the composite shaft 1 from one side, and then insert the base sleeve body 500 onto the shaft from the same side of the composite shaft 1. The recessed portion of the sleeve body 300 should be able to include the base sleeve body 500, and at this time, the recessed portion of the sleeve body 300 should be in front of the sleeve 500, and the sleeve 500 should be in front of the installation location;

[0077] S4: Place the other half of the magnetic bearing base body 400 on the half composite material shaft 1, support the composite material shaft 1 with temporary support objects on both sides near its working position, and buckle the two halves of the magnetic bearing base body 400, requiring that the magnetic bearing base body 400 as a whole should surround the composite material shaft 1 and cannot come into contact with the shaft 1; and use fastening bolts to preliminarily fix the ear-shaped parts on both sides of the magnetic bearing base body 400;

[0078] S5: After the outer axial magnetic bearing core 403 is wound with the coil 404 in one direction, it is installed in the groove of the disc-shaped part of the magnetic bearing base body 400 and fixed with screws, and a sensor for detecting axial related parameters is installed in the sensor placement hole 405;

[0079] S6: After installing the outer axial magnetic bearing and sensor 1, install sensor 2 for detecting radial related parameters in the sensor placement hole 503 on the base sleeve body 500; at S6, all the related parts that need to be installed and assembled should be in the following positions: Figure 2 As shown;

[0080] S7: Move the base sleeve body 500 axially so that it is sleeved on the magnetic bearing base body 400, and the top groove of the base sleeve body 500 should be aligned with the tooth-shaped front end recessed part of the magnetic bearing base body 400. At the same time, align the side wall holes of the base sleeve body 500 with the side wall holes of the magnetic bearing base body 400, pass various wiring through the small holes at the bottom of the magnetic bearing base body 400 and cling to the inner wall of the magnetic bearing base, lead out the sensor wiring, and use bolts to fix the base sleeve body 500 on the magnetic bearing base body 400 to completely fix the magnetic bearing base body 400;

[0081] S8: After the inner axial magnetic bearing core 501 is wound with the coil 502 in the same direction as step S5, it is installed in the groove on the top of the base sleeve 500 (because the groove designed here includes both the base sleeve 500 and the tooth-shaped front end depression of the magnetic bearing base body 400, it is recommended here that when the magnetic bearing core is fixed by screws, screw holes should be punched in both parts to strengthen the fixation);

[0082] S9: After installing the inner axial magnetic bearing, wind the radial magnetic bearing core 401 with the coil 402 in the same direction as step S5, pass the lead wire of the coil 402 through the small hole at the bottom of the hole of the magnetic bearing base body 400 and cling it to the inner wall of the magnetic bearing base, lead out the wiring, and then align the bottom thread of the core 401 with the bottom thread of the hole of the magnetic bearing base body 400, install it and tighten it;

[0083] S10: After all the parts are installed, move the sleeve body 300 axially, observe through the heat dissipation holes, stop moving when the edge of the hole for placing the radial magnetic bearing can be seen, leave a distance slightly larger than the working air gap of the axial electromagnetic component, and tighten the axial positioning bolt 2 firmly on the composite material shaft 1; after powering on to ensure that the present invention can work normally, remove the temporary support object mentioned in S4.

[0084] The magnetic bearing structure needs to be powered on and adjusted for the first time it works: first, power on the radial magnetic bearing coil 402 to make the radial electromagnetic component work in the working position, and axially align the inner and outer circles of axial electromagnetic components; then power on the inner axial magnetic bearing coil 502 and the outer axial magnetic bearing coil 404 to fine-tune the position of the sleeve assembly 3 on the composite material shaft 1; after adjusting to the left and right forces on the sleeve assembly 3, tighten the axial positioning bolt 2 to reinforce it on the composite material shaft 1 to ensure that the axial magnetic bearing works in the working position. When starting the magnetic bearing structure again, it should also be started in this power-on sequence.

[0085] When the magnetic bearing structure is shut down, wait until the rotor system stops rotating completely; first stop the power supply to the inner axial magnetic bearing coil 502 and the outer axial magnetic bearing coil 404, and wait for a while to complete the heat dissipation; if the rotor system has auxiliary bearing support, the power supply to the radial magnetic bearing coil 402 can be directly stopped; if the rotor system does not have auxiliary bearing support, temporary support is needed to support the rotor, and then stop the power supply to the radial magnetic bearing coil 402. When the magnetic bearing structure is shut down, check the working air gap to ensure that no foreign matter can enter to prevent damage to the bearing components when starting again.

Claims

1. A magnetic bearing structure for a composite shaft, characterized in that: The invention comprises a shaft sleeve assembly (3), a magnetic bearing base assembly (4), and a base sleeve assembly (5); the shaft sleeve assembly (3) comprises a shaft sleeve body (300), an inner permanent magnet ring (301), a rotor ring (302), and an outer permanent magnet ring (303); the shaft sleeve body (300) is sleeved on the outer side of a composite material shaft (1) and fixed to the composite material shaft (1); the inner permanent magnet ring (301) is embedded in the inner bottom surface of the shaft sleeve body (300); the rotor ring (302) is embedded in the inner circumferential surface of the shaft sleeve body (300); the outer permanent magnet ring (303) is embedded in one end surface of the shaft sleeve body (300); the magnetic bearing base assembly (4) comprises a magnetic bearing base body (400), a radial electromagnetic component, an outer axial electromagnetic component, and a first sensor; the base sleeve assembly (5) comprises a base sleeve body (500), an inner axial electromagnetic component, a second sensor, and a second magnetic component; The seat sleeve body (500) is placed inside the shaft sleeve body (300); a plurality of inner axial electromagnetic components are embedded at intervals along the circumferential direction on one side surface of the sleeve body (500) and are respectively aligned with the inner permanent magnet ring (301); the magnetic bearing base body (400) is penetrated in the base sleeve body (500); a plurality of radial electromagnetic components are disposed at intervals along the circumferential direction of the magnetic bearing base body (400) and are respectively penetrated in the magnetic bearing base body (400) and the base sleeve body (500) in sequence; the radial electromagnetic components cooperate with the rotor ring (302); a plurality of outer axial electromagnetic components are embedded at intervals along the circumferential direction on one side surface of the magnetic bearing base body (400) and are respectively aligned with the outer permanent magnet ring (303); at least one sensor 1 is installed on the magnetic bearing base body (400); and at least one sensor 2 is installed on the base sleeve body (500).

2. A magnetic bearing structure for a composite material shaft according to claim 1, characterized in that: An annular inner permanent magnet ring groove (304) is provided on the inner bottom surface of the shaft sleeve body (300), the inner permanent magnet ring (301) is installed in the inner permanent magnet ring groove (304), a circle of rotor ring groove (305) is provided on the inner circumferential surface of the shaft sleeve body (300), the rotor ring (302) is installed in the rotor ring groove (305), an annular outer permanent magnet ring groove (306) is provided on the end surface of the shaft sleeve body (300) opposite to the magnetic bearing base body (400), the outer permanent magnet ring (303) is installed in the outer permanent magnet ring groove (306), and a plurality of heat dissipation holes (307) are also provided at intervals on the outer circumferential surface of the shaft sleeve body (300).

3. The magnetic bearing structure for a composite material shaft according to claim 1, characterized in that: The radial electromagnetic component comprises a radial magnetic bearing core (401) and a radial magnetic bearing coil (402); the radial magnetic bearing core (401) is a columnar structure; the radial magnetic bearing coil (402) is wound on the outer peripheral surface of the radial magnetic bearing core (401); the radial magnetic bearing core (401) is sequentially inserted into a magnetic bearing base body (400) and a base sleeve body (500) so that the radial magnetic bearing coil (402) is located in the base sleeve body (500); and one end of the radial magnetic bearing core (401) is opposite to the rotor ring (302).

4. A magnetic bearing structure for a composite material shaft according to claim 3, characterized in that: The outer axial electromagnetic component comprises an outer axial magnetic bearing core (403) and an outer axial magnetic bearing coil (404); the outer axial magnetic bearing core (403) is a rectangular parallelepiped structure, and the outer axial magnetic bearing coil (404) is wound around the outer axial magnetic bearing core (403); the outer axial magnetic bearing core (403) is embedded in the magnetic bearing base body (400); and one of the non-winding surfaces of the outer axial magnetic bearing core (403) is opposite to the outer permanent magnet ring (303).

5. A magnetic bearing structure for a composite material shaft according to claim 4, characterized in that: The outer axial magnetic bearing coil (404) and the radial magnetic bearing coil (402) are wound in the same direction.

6. The magnetic bearing structure for a composite material shaft according to claim 1, characterized in that: The magnetic bearing base body (400) is also provided with a plurality of base sensor placement holes (405) spaced apart in the circumferential direction on a side surface on which the outer axial electromagnetic component is installed, and a sensor 1 is installed in the base sensor placement hole (405).

7. The magnetic bearing structure for a composite material shaft according to claim 1, characterized in that: The inner axial electromagnetic component comprises an inner axial magnetic bearing core (501) and an inner axial magnetic bearing coil (502); the inner axial magnetic bearing core (501) is a rectangular parallelepiped structure, and the inner axial magnetic bearing coil (502) is wound around the inner axial magnetic bearing core (501); the inner axial magnetic bearing core (501) is embedded in one end surface of the base sleeve body (500); and one of the non-wrap surfaces of the inner axial magnetic bearing core (501) is opposite to the inner permanent magnet ring (301).

8. The magnetic bearing structure for a composite material shaft according to claim 1, characterized in that: A plurality of sleeve sensor placement holes (503) are provided on the outer peripheral surface of the base sleeve body (500) at intervals in the circumferential direction, and the second sensor is installed in the sleeve sensor placement hole (503).

9. The magnetic bearing structure for a composite material shaft according to claim 1, characterized in that: The magnetic pole directions of the inner permanent magnetic ring (301) and the outer permanent magnetic ring (303) are opposite.

10. A method for assembling a magnetic bearing structure for a composite material shaft according to any one of claims 1 to 9, characterized in that The following steps are involved: S1: determining a position to be installed, and fixing one half of the magnetic bearing base body (400) to the position to be installed; S2: fixing the inner permanent magnet ring (301), the rotor ring (302), and the outer permanent magnet ring (303) on the shaft sleeve body (300) respectively; S3: sleeve the shaft sleeve body (300) onto the composite shaft (1), and then sleeve the base sleeve body (500) onto the composite shaft (1), so that the base sleeve body (500) and the recessed portion of the shaft sleeve body (300) are spaced apart and face each other; S4: The composite material shaft (1) is supported as a whole near the position to be installed by a temporary support body, and the other half of the magnetic bearing base body (400) is sleeved on the composite material shaft (1), and the two halves of the magnetic bearing base body (400) are connected to form a complete magnetic bearing base body (400), so that the magnetic bearing base body (400) and the composite material shaft (1) are spaced and coaxially aligned; S5: Fix the outer axial electromagnetic component on the magnetic bearing base body (400) and install sensor 1; S6: Install the second sensor on the base sleeve body (500); S7: Move the base sleeve body (500) axially so that it is sleeved on the magnetic bearing base body (400), and the top groove of the base sleeve body (500) is aligned with the tooth-shaped front end recessed portion of the magnetic bearing base body (400). At the same time, the side wall holes of the base sleeve body (500) are aligned with the side wall holes of the magnetic bearing base body (400). Pass the wiring of sensor 1 and sensor 2 through the small hole at the bottom of the magnetic bearing base body (400) and lead them out close to the inner wall thereof. Use bolts to fix the base sleeve body (500) on the magnetic bearing base body (400) so that the magnetic bearing base body (400) is completely fixed. S8: Installing the inner axial electromagnetic component on the base sleeve body (500); S9: Install the radial electromagnetic component, and sequentially pass the radial electromagnetic component through the base sleeve body (500) and the magnetic bearing base body (400) and thread the radial electromagnetic component with the magnetic bearing base body (400); S10: After all parts are installed, the shaft sleeve body (300) is axially moved so that it is sleeved on the base sleeve body (500). After it is in place, the shaft sleeve body (300) is fixed to the composite material shaft (1) by means of axial positioning bolts (2). After power is turned on to ensure that the bearing structure can work normally, the temporary support body of S4 is removed.

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