An integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system
Patent Information
- Application Number
- CN202522120641.7
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2025-10-01
- Publication Date
- 2026-09-01
- Estimated Expiration
- 2035-10-01
AI Technical Summary
[0002]传统泵送系统普遍采用大功率电机、调速设备与水泵分体布置的模式，存在占地面积大、现场安装对中复杂、基建成本高及效率易受损等问题，永磁涡流调速技术虽能实现高效、非接触的扭矩传递与软启动，但传统的分散式布局未能充分发挥其结构紧凑的优势
本实用新型所述一种一体式撬装结构永磁柔性非接触节能调速水泵系统，通过嵌入式控制、磁场耦合与机械传动的深度融合，实现了高效、智能且可靠的非接触式动力传递与调速，通过星轮件灵活调节输出扭矩与转速，并利用直线执行机构精准控制气隙，以优化永磁转子与导体转子间的磁场耦合效应，从而无接触地传递扭矩并调节输出速度，集成化的水泵流量、水泵压力和滑差监测系统实时反馈运行状态，通过PID算法实现气隙的闭环控制，既保障了传输效率与系统稳定性，又能智能在线诊断潜在故障。
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Figure CN224705907U_ABST
Abstract
Description
Technical Field
[0001] This utility model relates to the field of speed regulation equipment technology, specifically an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed regulation water pump system. Background Technology
[0002] Traditional pumping systems generally adopt a separate layout of high-power motors, speed control equipment, and water pumps, which has problems such as large footprint, complex on-site installation and alignment, high infrastructure costs, and easy loss of efficiency. Although permanent magnet eddy current speed control technology can achieve efficient, non-contact torque transmission and soft start, the traditional distributed layout has failed to give full play to its compact structural advantages. Utility Model Content
[0003] Therefore, in order to overcome the above-mentioned shortcomings, this utility model provides an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system.
[0004] This invention is implemented as follows: An integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system is constructed. The device includes a fixed frame; a high-power motor with driving function is fixedly mounted on the left side plate of the fixed frame via bolts; the end of the right transmission shaft of the high-power motor is fixedly mounted to a speed-changing assembly; a conductor rotor is fixedly mounted on the right side of the speed-changing assembly via an insertion connection; a permanent magnet rotor is rotatably mounted on the right side of the conductor rotor; the permanent magnet rotor is rotatably mounted inside a magnetic shielding cylinder, and the magnetic shielding cylinder is slidably connected to the outer fixed seat of the speed-changing assembly via a straight rod; a connector is fixedly mounted on the right side of the permanent magnet rotor, and the right end of the connector is fixedly mounted to the input gear of the gearbox; the output gear at the bottom of the gearbox is fixedly mounted to the internal actuator rod of the water pump; both the speed-changing assembly and the bottom of the magnetic shielding cylinder are provided with screw holes, and a linear actuator is installed inside the screw holes via threaded transmission; an embedded controller with control function is fixedly mounted on the front crossbar of the fixed frame.
[0005] Preferably, the linear actuator specifically comprises a worm gear transmission box fixedly installed on the side of the transmission assembly; a servo motor with driving function is fixedly installed at the input end of the worm gear transmission box; a hollow lead screw is inserted and fixedly connected to the central hole of the worm gear in the worm gear transmission box, and a current output device is fixedly installed at the front and rear ends of the hollow lead screw; a coil is provided inside the hollow lead screw, and the coil is connected to the current output device through a cable; a coil sleeve is provided on the outside of the hollow lead screw, and an air gap exists between the hollow lead screw and the coil sleeve through magnetic force; the coil sleeve is fixedly installed in the bottom ear plate of the transmission assembly; a Hall effect sensor is fixedly installed on the side of the transmission assembly by bolts; and a permanent magnet marker block is fixedly installed at the side end of the hollow lead screw.
[0006] Preferably, a current sensor with data acquisition function is fixedly installed on the input cable of the high-power motor; a photoelectric sensor is fixedly installed on the top side of the conductor rotor by bolts, and a shielding shell is provided on the outside of the photoelectric sensor.
[0007] Preferably, the left end face of the magnetic shielding cylinder is a concave groove, and a photosensitive plate is fixedly installed inside the concave groove; an infrared temperature sensor with temperature data acquisition function is fixedly installed on the straight rod on the front side of the magnetic shielding cylinder.
[0008] Preferably, the transmission assembly includes a protective shell fixedly mounted on the right end of the straight plate of the fixed frame by bolts; the protective shell is provided with a star wheel component with transmission function, and the star wheel component includes a gear ring fixedly mounted inside the protective shell, planetary gears meshing and driving inside the gear ring, a connecting frame inserted and driving on the right side of the planetary gears, and a sun gear meshing and driving on the side of the planetary gears; the right end of the connecting frame of the star wheel component is fixedly mounted to the conductor rotor and the heat sink respectively.
[0009] Preferably, a positioning plate is fixedly installed on the right end face of the protective shell by bolts, and a heat dissipation plate is rotatably arranged on the side of the positioning plate; the side of the heat dissipation plate is in contact with the left end face of the conductor rotor.
[0010] Preferably, the heat sink has annularly distributed heat dissipation holes inside the sink body, and heat dissipation fins arranged in annular array are fixedly installed on the right side of the sink body.
[0011] Preferably, the signal input terminal of the embedded controller is electrically connected to the current sensor, photoelectric sensor, and infrared temperature sensor; the embedded controller integrates a PID control module, the output terminal of which is electrically connected to the servo motor of the linear actuator, used to dynamically adjust the air gap between the permanent magnet rotor and the conductor rotor according to the sensor data.
[0012] Preferably, a non-contact sealing ring is provided at the mating gap between the magnetic shielding cylinder and the conductor rotor, and the sealing ring is made of polytetrafluoroethylene material.
[0013] This utility model has the following advantages: This utility model provides an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system, which, compared with similar equipment, has the following improvements: This utility model describes an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system. Through the deep integration of embedded control, magnetic field coupling, and mechanical transmission, it achieves efficient, intelligent, and reliable non-contact power transmission and speed regulation. The output torque and speed are flexibly adjusted through the star wheel component, and the air gap is precisely controlled by the linear actuator to optimize the magnetic field coupling effect between the permanent magnet rotor and the conductor rotor. This allows for contactless torque transmission and output speed regulation. The integrated water pump flow, water pump pressure, and slip monitoring system provides real-time feedback on the operating status. The closed-loop control of the air gap is achieved through the PID algorithm, which not only ensures transmission efficiency and system stability but also enables intelligent online diagnosis of potential faults.
[0014] The present invention discloses an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system. This application adopts a non-contact transmission method of conductor rotor and permanent magnet rotor, which eliminates shaft alignment problems and traditional bearing problems, and has the advantages of reliability and small footprint. Attached Figure Description
[0015] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is an exploded view of the fixed frame and linear actuator of this utility model; Figure 3 This is an exploded structural diagram of the transmission component of this utility model; Figure 4 This is the utility model Figure 2 Enlarged structural diagram at point A; Figure 5 This is a schematic diagram of the linear actuator structure of this utility model.
[0016] The components include: 1. Fixed frame; 2. High-power motor; 3. Speed change assembly; 4. Conductor rotor; 5. Permanent magnet rotor; 6. Magnetic shielding cylinder; 7. Connector; 8. Gearbox; 9. Water pump; 10. Linear actuator; 11. Embedded controller; 12. Current sensor; 13. Photoelectric sensor; 14. Photosensitive plate; 15. Infrared temperature sensor; 31. Protective shell; 32. Star wheel component; 33. Positioning plate; 34. Heat sink; 101. Worm gear transmission box; 102. Servo motor; 103. Hollow lead screw; 104. Coil sleeve; 105. Current output device; 106. Hall effect sensor; 107. Permanent magnet marker block. Detailed Implementation
[0017] The following is in conjunction with the appendix Figures 1-5The principles and features of this utility model are described below. The examples given are for illustrative purposes only and are not intended to limit the scope of this utility model. The utility model is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. It should be noted that the drawings are all in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of this utility model.
[0018] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicating the orientation or positional relationship, are based on the orientation or positional relationship shown in the accompanying drawings and are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this utility model. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0019] In the description of this utility model, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "setting" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances. The embodiments of this utility model will now be described based on its overall structure.
[0020] Example 1: Please see Figures 1-5This utility model discloses an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system, including a fixed frame 1; a high-power motor 2 with driving function is fixedly installed on the left side plate of the fixed frame 1 by bolts; the end of the transmission shaft on the right side of the high-power motor 2 is fixedly installed to the speed change assembly 3; a conductor rotor 4 is fixedly installed on the right side of the speed change assembly 3 by plug-in connection; a permanent magnet rotor 5 is rotatably arranged on the right side of the conductor rotor 4; the permanent magnet rotor 5 is rotatably arranged inside the magnetic shielding cylinder 6, and the magnetic shielding cylinder 6 is slidably connected to the outer fixed seat of the speed change assembly 3 through a straight rod; a connector 7 is fixedly installed on the right side of the permanent magnet rotor 5, and the right end of the connector 7 is fixedly installed to the input gear of the gearbox 8; the output gear at the bottom of the gearbox 8 is fixedly installed to the internal actuator rod of the water pump 9; both the speed change assembly 3 and the magnetic shielding cylinder 6 are provided with screw hole seats at the bottom, and a linear actuator 10 is provided with threaded drive inside the screw hole seats; the front crossbar of the fixed frame 1 is fixedly installed. An embedded controller 11 with control function is installed; the linear actuator 10 is specifically composed of a worm gear transmission box 101 fixedly installed on the side of the transmission assembly 3; a servo motor 102 with driving function is fixedly installed at the input end of the worm gear transmission box 101; a hollow lead screw 103 is inserted and fixedly connected to the worm gear center hole of the worm gear transmission box 101, and a current output device 105 is fixedly installed at the front and rear ends of the hollow lead screw 103; a coil is installed inside the hollow lead screw 103, and the coil is connected to the current output device 105 through a cable; a coil sleeve 104 is installed on the outside of the hollow lead screw 103, and there is an air gap between the hollow lead screw 103 and the coil sleeve 104 through magnetic force; the coil sleeve 104 is fixedly installed in the bottom ear plate of the transmission assembly 3; a Hall effect sensor 106 is fixedly installed on the side of the transmission assembly 3 by bolts; a permanent magnet marker block 107 is fixedly installed at the side end of the hollow lead screw 103.
[0021] A current sensor 12 with data acquisition function is fixedly installed on the input cable of the high-power motor 2; a photoelectric sensor 13 is fixedly installed on the top side of the conductor rotor 4 by bolts, and a shielding shell is provided on the outside of the photoelectric sensor 13.
[0022] The left end face of the magnetic shielding cylinder 6 is concave, and a photosensitive plate 14 is fixedly installed inside the concave groove; an infrared temperature sensor 15 with temperature data acquisition function is fixedly installed on the straight rod on the front side of the magnetic shielding cylinder 6.
[0023] The signal input terminal of the embedded controller 11 is electrically connected to the current sensor 12, the photoelectric sensor 13 and the infrared temperature sensor 15; the embedded controller 11 integrates a PID control module, whose output terminal is electrically connected to the servo motor of the linear actuator 10, and is used to dynamically adjust the air gap between the permanent magnet rotor 5 and the conductor rotor 4 according to the sensor data.
[0024] A non-contact sealing ring is provided at the mating gap between the magnetic shielding cylinder 6 and the conductor rotor 4, and the sealing ring is made of polytetrafluoroethylene material.
[0025] Example 2: Please see Figures 1-5 This utility model discloses an integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system. Compared with Embodiment 1, this embodiment further includes: a speed-changing component 3 comprising a protective shell 31 fixedly mounted on the right end of the straight plate of the fixed frame 1 by bolts; a star wheel component 32 with speed-changing function is provided inside the protective shell 31, and the star wheel component 32 includes a gear ring fixedly mounted inside the protective shell 31, planetary gears meshing and driving inside the gear ring, a connecting frame inserted and driving on the right side of the planetary gears, and a sun gear meshing and driving on the side of the planetary gears; the right end of the connecting frame of the star wheel component 32 is fixedly mounted to the conductor rotor 4 and the heat sink 34 respectively.
[0026] A positioning plate 33 is fixedly installed on the right end face of the protective shell 31 by bolts, and a heat sink 34 is rotatably installed on the side of the positioning plate 33; the side of the heat sink 34 is in contact with the left end face of the conductor rotor 4; the heat sink 34 has annularly distributed heat dissipation holes inside the plate body, and heat dissipation fins arranged in annular array are fixedly installed on the right side of the plate body.
[0027] The working principle of the integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system described above is as follows: First, when using this device, place it in the work area, and then connect it to an external power source to provide the power required for its operation. Secondly, the high-power motor 2 is driven by the embedded controller 11 to transmit power to the speed change assembly 3 through the transmission shaft. Here, the output torque and speed are adjusted and controlled by the star wheel 32 inside the speed change assembly 3. According to the actual working requirements, the star wheel 32 is set as a speed-increasing gear structure to improve the torque transmission density and efficiency. Conversely, when the star wheel 32 is set as a speed-reducing gear structure, it directly outputs low speed and high torque to achieve speed adjustment and output to the conductor rotor 4. During the rotation, the conductor rotor 4 has a magnetic field coupling with the permanent magnet rotor 5. The rotating permanent magnetic field cuts the magnetic field lines in the conductor disk and generates a strong eddy current. The eddy current induces a magnetic field that interacts with the permanent magnetic field, thus "dragging" the permanent magnet rotor 5 to rotate synchronously. Third, simultaneously, the servo motor 102 in the linear actuator 10 drives the hollow lead screw 103 via the worm gear transmission box 101 to adjust the distance between the speed change assembly 3 and the permanent magnet rotor 5. Here, current is supplied through the current output device 105 into the hollow lead screw 103, simultaneously supplying current to the coil sleeve 104, thereby generating a magnetic force that cancels out the radial attraction of the hollow lead screw 103. This causes the coil sleeve 104 to stably suspend in the center of the hollow lead screw 103. Because multiple sets of positioning crossbars are installed between the housing of the speed change assembly 3 and the magnetic shielding cylinder 6, the interaction between the coil sleeve 104 and the hollow lead screw 103 generates a tangential force along the thread direction, pushing the coil sleeve 104 to drive the speed change assembly 3 forward or backward. The linear motion is ensured by the limit of the crossbars, achieving zero wear. The revolutionary performance of theoretically unlimited lifespan, no lubrication, and extremely high ultimate speed allows for adjustment of the air gap between the conductor rotor 4 and the permanent magnet rotor 5, achieving non-contact torque transmission and speed regulation. Here, the embedded controller 11 reads the Hall sensor 106 and the permanent magnet marker block 107 to adjust the values. If a strong magnetic field signal is detected, it is known that the transmission assembly 3 platform is in the initial position. The adjustment of the air gap, through the mirrored screw thread design of the hollow lead screw of the linear actuator 10, can synchronously drive the transmission assembly 3 and the magnetic shielding cylinder 6 to move towards or opposite each other, thereby precisely controlling the relative position of the permanent magnet rotor 5 and the conductor rotor 4. The power output by the permanent magnet rotor 5 is transmitted to the gearbox 8 through the connector 7, and after gear speed change, it drives the actuator of the water pump 9 to achieve the pumping function. Fourth, the current sensor 12 and infrared temperature sensor 15 installed in the system monitor the current, rotor speed, and operating temperature of the high-power motor in real time, and transmit the data to the embedded controller 11. The photoelectric sensor 13 and the photosensitive plate 14 installed here can detect the speed difference between the conductor rotor 4 and the permanent magnet rotor 5. The slip is calculated here using a formula. ,in, This is the input speed of the high-power motor 2. For the output speed of connector 7, slip This directly reflects the magnitude of the transmitted torque; the stronger the magnetic field coupling, the smaller the slip difference under the same load; if the slip difference increases abnormally, under the condition that the load remains unchanged, it is very likely that the permanent magnet has demagnetized, resulting in a weakening of the magnetic field strength and a decrease in the torque transmission capacity; the embedded controller 11 dynamically adjusts the linear actuator 10 through the built-in PID algorithm to achieve closed-loop control of the air gap, thereby optimizing the speed regulation performance and ensuring the stable operation of the system; in addition, the heat sink 34 contacts the conductor rotor 4 and enhances heat dissipation through heat sink fins to ensure the reliability of the system under high temperature conditions.
[0028] This utility model provides an improved integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system. Through the deep integration of embedded control, magnetic field coupling and mechanical transmission, it achieves efficient, intelligent and reliable non-contact power transmission and speed regulation. The output torque and speed are flexibly adjusted by the star wheel component 32, and the air gap is precisely controlled by the linear actuator 10 to optimize the magnetic field coupling effect between the permanent magnet rotor 5 and the conductor rotor 4, thereby transmitting torque and regulating the output speed without contact. The integrated water pump flow, water pump pressure and slip monitoring system provides real-time feedback on the operating status. The closed-loop control of the air gap is achieved through the PID algorithm, which not only ensures transmission efficiency and system stability, but also intelligently diagnoses potential faults online.
[0029] The above describes the basic principles, main features, and advantages of this utility model. All standard parts used in this utility model can be purchased from the market, and irregularly shaped parts can be customized according to the description and drawings. The specific connection methods for each part all adopt conventional methods such as bolts, rivets, and welding, which are mature technologies in the prior art. The machinery, parts, and equipment all adopt conventional models in the prior art, and the circuit connections adopt conventional connection methods in the prior art, which will not be detailed here.
[0030] The above description of the disclosed embodiments enables those skilled in the art to make or use 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 to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims
1. An integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system, characterized in that: Includes a fixed frame (1); a high-power motor (2) with driving function is fixedly installed on the left side plate of the fixed frame (1) by bolts; the end of the transmission shaft on the right side of the high-power motor (2) is fixedly installed to the speed change assembly (3); a conductor rotor (4) is fixedly installed on the right side of the speed change assembly (3) by plugging; a permanent magnet rotor (5) is rotatably arranged on the right side of the conductor rotor (4); the permanent magnet rotor (5) is rotatably arranged inside the magnetic shielding cylinder (6), and the magnetic shielding cylinder (6) is slidably connected to the outer fixed seat of the speed change assembly (3) through a straight rod; A connector (7) is fixedly installed on the right side of the permanent magnet rotor (5), and the right end of the connector (7) is fixedly installed with the input gear of the gearbox (8); the output gear at the bottom of the gearbox (8) is fixedly installed with the internal actuator rod of the water pump (9); the bottom of the speed change assembly (3) and the magnetic shielding cylinder (6) are both provided with screw hole seats, and the screw hole seats are provided with linear actuators (10) for threaded transmission; an embedded controller (11) with control function is fixedly installed on the front crossbar of the fixed frame (1); Specifically, the linear actuator (10) consists of a worm gear transmission box (101) fixedly installed on the side of the transmission assembly (3); a servo motor (102) with driving function is fixedly installed at the input end of the worm gear transmission box (101); a hollow lead screw (103) is inserted and fixedly connected to the worm wheel center hole of the worm gear transmission box (101), and a current output device (105) is fixedly installed at the front and rear ends of the hollow lead screw (103); a coil is provided inside the hollow lead screw (103), and the coil is connected to the power supply. The output device (105) is connected by a cable; a coil sleeve (104) is provided on the outside of the hollow screw (103), and there is an air gap between the hollow screw (103) and the coil sleeve (104) through magnetic field force; the coil sleeve (104) is fixedly installed in the bottom ear plate of the transmission assembly (3); a Hall effect sensor (106) is fixedly installed on the side of the transmission assembly (3) by bolts; a permanent magnet marker block (107) is fixedly installed at the end of the side of the hollow screw (103).
2. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 1, characterized in that: A current sensor (12) with data acquisition function is fixedly installed on the input cable of the high-power motor (2); a photoelectric sensor (13) is fixedly installed on the top side of the conductor rotor (4) by bolts, and a shielding shell is provided on the outside of the photoelectric sensor (13).
3. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 2, characterized in that: The left end face of the magnetic shielding cylinder (6) is concave, and a photosensitive plate (14) is fixedly installed inside the concave groove; an infrared temperature sensor (15) with temperature data acquisition function is fixedly installed on the straight rod on the front side of the magnetic shielding cylinder (6).
4. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 3, characterized in that: The transmission assembly (3) includes a protective shell (31) fixedly mounted on the right end of the straight plate of the fixed frame (1) by bolts; the protective shell (31) is provided with a star wheel component (32) with a transmission function, and the star wheel component (32) includes a gear ring fixedly mounted inside the protective shell (31), a planetary gear meshing and driving inside the gear ring, a connecting frame inserted and driving on the right side of the planetary gear, and a sun gear meshing and driving on the side of the planetary gear; the right end of the connecting frame of the star wheel component (32) is fixedly mounted to the conductor rotor (4) and the heat sink (34) respectively.
5. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 4, characterized in that: The right end face of the protective shell (31) is fixedly installed with a positioning plate (33) by bolts, and a heat sink (34) is rotatably provided on the side of the positioning plate (33); the side of the heat sink (34) is in contact with the left end face of the conductor rotor (4).
6. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 5, characterized in that: The heat sink (34) has annularly distributed heat dissipation holes inside the sink body, and heat dissipation fins arranged in annular array are fixedly installed on the right side of the sink body.
7. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 6, characterized in that: The signal input terminal of the embedded controller (11) is electrically connected to the current sensor (12), the photoelectric sensor (13) and the infrared temperature sensor (15); the embedded controller (11) integrates a PID control module, whose output terminal is electrically connected to the servo motor of the linear actuator (10), and is used to dynamically adjust the air gap between the permanent magnet rotor (5) and the conductor rotor (4) according to the sensor data.
8. The integrated skid-mounted permanent magnet flexible non-contact energy-saving speed-regulating water pump system according to claim 7, characterized in that: A non-contact sealing ring is provided at the fitting gap between the magnetic shielding cylinder (6) and the conductor rotor (4), and the sealing ring is made of polytetrafluoroethylene material.