Electric spindle of composite stator
Patent Information
- Application Number
- CN202511829749.1
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-05
- Publication Date
- 2026-03-06
Smart Images
Figure CN121607667A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of electric spindle technology, and more particularly to an electric spindle with a composite stator. Background Technology
[0002] As a core functional component of modern high-end CNC machine tools, the electric spindle represents the evolution of the machine tool industry towards high speed, high precision, and high efficiency. By integrating the spindle and drive motor into one unit, it eliminates traditional intermediate transmission links such as belts and gears, achieving direct motor drive and significantly improving transmission efficiency and dynamic response performance. The built-in motor of the electric spindle, especially the stator windings, generates a large amount of Joule heat during high-speed operation, while the rotor also generates heat due to eddy current effects and friction. If this heat cannot be dissipated effectively and in a timely manner, it will cause thermal elongation and deformation of the spindle, severely restricting the improvement of machining accuracy. To address this problem, modern electric spindles generally adopt forced circulation cooling technology, which involves pumping coolant into a spiral flow channel inside the spindle housing through an external cooling system to cool the stator. More advanced technologies require cooling the rotor and even the cutting area. This necessitates machining a channel in the center of the high-speed rotating rotor and introducing coolant to guide it to the tool tip. This inevitably involves the design and sealing of the rotary joint—the fluid transmission interface between rotating and stationary components.
[0003] This joint is a crucial interface connecting the stationary high-pressure coolant pipeline to the high-speed rotating spindle rotor. Its core technical requirement is to achieve absolute sealing while ensuring high-pressure, high-flow-rate coolant transmission, preventing leakage of high-pressure coolant from the rotating interface. Loss of sealing will cause high-pressure coolant to spray outwards, directly contaminating the machining environment, corroding precision machine tool components and electrical systems, and causing short circuits and corrosion failures. However, ensuring long-term effective sealing presents a significant challenge, especially under ultra-high speed conditions. In traditional contact mechanical seals, the relative sliding friction between the sealing rings intensifies dramatically, generating a large amount of frictional heat that accelerates wear. This decrease in seal reliability due to friction, wear, and vibration at high speeds directly restricts the service life and operational reliability of the electric spindle at its maximum speed, hindering its improvement. Summary of the Invention
[0004] The purpose of this invention is to address the problems existing in the prior art by proposing a non-contact composite stator electric spindle that can adapt to ultra-high speed conditions, has low wear, and a long service life.
[0005] The technical solution of the present invention: an electric spindle with a composite stator, comprising a shaft body, a stator fixedly installed inside the shaft body, and a rotor made of composite material rotatably installed inside the shaft body, wherein the rotor shaft has a through hole, and further comprising: A shaft cooling component includes a connector, a connecting pipe, and a connecting seat that are fixedly installed at one end of the shaft and are interconnected with each other. It also includes a rotating connector that connects the connecting seat to the through hole. The rotating connector includes a fixed cover that is fixedly installed on the connecting seat and a rotating plate that is fixedly installed at one end of the rotor. The rotating plate and the fixed cover are rotatably connected by a bearing. Multiple first protruding rings are fixedly installed on the fixed cover, and multiple second protruding rings are fixedly installed on the rotating plate. A labyrinth channel is formed between the first and second protruding rings. The middle part of the fixed cover and the rotating plate is provided with an infusion chamber that communicates with the labyrinth channel, through holes and connecting seats. An air chamber that communicates with the labyrinth channel is provided inside. Multiple air inlet connectors are arranged in a circular array on the air chamber and an exhaust connector is provided. The fixed cover is provided with a drainage assembly for discharging gas-liquid mixture. The drainage assembly includes a drainage connector that communicates with the labyrinth channel. The control system controls the pressure difference between air and hydraulic pressure within the labyrinth passage by controlling the opening and closing of the air inlet, exhaust, and drain connectors. Optionally, a first solenoid valve is fixedly installed on the outside of the shaft. One end of the first solenoid valve is connected to a plurality of air inlet connectors through a first air pipe. A second air pipe is fixedly installed on the other end of the first solenoid valve. The other end of the second air pipe is connected to an air pump system.
[0006] Optionally, a second solenoid valve is fixedly installed on the outer side of the shaft. One end of the second solenoid valve is connected to the exhaust connector through a third air pipe, and a fourth air pipe is fixedly installed on the other end of the second solenoid valve. A muffler is fixedly installed on the other end of the fourth air pipe.
[0007] Optionally, the drainage assembly further includes an electrically controlled valve fixedly installed on the outside of the shaft, the electrically controlled valve being connected to the drainage connector via a first drainage pipe, and a second drainage pipe being fixedly installed at the other end of the electrically controlled valve.
[0008] Optionally, a fluid delivery system for inputting high-pressure coolant into a connector is installed on the outside of the shaft. The fluid delivery system includes a tank for storing coolant, and one end of the second drain pipe is connected to a degassing device, which is in communication with the tank.
[0009] Optionally, the shaft body is provided with a pressure relief hole, which communicates with the interior of the shaft body and is located on one side of the rotating plate.
[0010] Optionally, a liquid level detection component is installed inside the fixed cover to detect the position of the coolant inside the labyrinth channel.
[0011] Optionally, the liquid level detection assembly includes multiple sets of conductors fixedly mounted on the first convex ring. Each set of conductors includes two conductive contacts. A power supply and a signal device are installed in the shaft body. One end of the power supply is connected to one of the conductive contacts through a first wire, and the other end of the power supply is connected to the signal device through a second wire. The signal device is connected to the other conductive contact through a third wire.
[0012] Optionally, an imbalance sealing assembly is installed inside the fixed cover. The imbalance sealing assembly includes a groove inside the fixed cover and a sealing ring slidably installed in the groove. The rotating plate is provided with a groove for accommodating the sealing ring. The fixed cover is provided with an air supply hole communicating with the groove. A third solenoid valve is fixedly installed on the outside of the shaft. The third solenoid valve is connected to the air supply hole through a fifth air pipe. The other end of the third solenoid valve is connected to the air pump system through a sixth air pipe.
[0013] Optionally, a pressure sensor with an air chamber connected to the fixed cover is fixedly installed on the fixed cover, and a hydraulic sensor for checking the hydraulic pressure in the maze passage is fixedly installed on the fixed cover. In summary, this application includes at least one of the following beneficial technical effects: This application combines composite rotor materials with a non-contact labyrinth gas seal, which significantly reduces the friction, wear and heat generation problems caused by traditional contact seals at ultra-high speeds. This greatly improves the service life and operational reliability of the electric spindle at its maximum speed. By adopting a dynamic pressure control system and an automatic drainage mechanism, the problem of gas dissolving in coolant and causing bubbles in high-pressure gas seals is effectively solved. This avoids the decrease in cooling efficiency, pump cavitation and lubrication failure caused by bubbles, and ensures stable tool cooling and machining accuracy. Furthermore, by integrating liquid level monitoring and emergency mechanical seal devices, the system's response capability and safety to faults such as pressure imbalance are improved, preventing equipment damage and environmental pollution caused by coolant leakage. The overall structure achieves efficient internal cooling of the rotor and reliable sealing of the rotating interface, meeting the comprehensive requirements of high-end CNC machine tools for high speed, high precision, high reliability and long service life. Attached Figure Description
[0014] Figure 1 Schematic diagram of the electric spindle structure Figure 1 ; Figure 2 Schematic diagram of the electric spindle structure Figure 2 ; Figure 3 for Figure 1 A magnified view of a section at point A in the middle; Figure 4 for Figure 2 A magnified view of a section at point B in the middle; Figure 5 Schematic diagram of the shaft cooling component Figure 1 ; Figure 6 Schematic diagram of the shaft cooling component Figure 2 ; Figure 7 This is a structural diagram of the fixed cover and the rotating plate; Figure 8 This is a schematic diagram of the liquid level detection component; Figure 9 This is a schematic diagram of the control system.
[0015] Reference numerals: 1. Shaft; 11. Stator; 12. Rotor; 121. Through hole; 2. Shaft cooling component; 21. Joint; 211. Connecting pipe; 212. Connecting seat; 22. Fixing cover; 221. First convex ring; 23. Rotating plate; 231. Second convex ring; 24. Bearing; 25. Labyrinth passage; 251. Infusion chamber; 252. Air chamber; 253. Air inlet connector; 254. Air outlet connector; 255. First solenoid valve; 256. Second solenoid valve; 257. First air pipe; 258. Third air pipe; 259. Second air pipe; 2510. Fourth air pipe; 2 6. Liquid level detection component; 261. Conductive contact; 262. Power supply; 263. Signal device; 264. First wire; 265. Second wire; 266. Third wire; 27. Drainage component; 271. Drainage connector; 272. Electrically controlled valve; 273. Drainage pipe; 274. Second drainage pipe; 28. Pressure reducing hole; 29. Imbalance sealing component; 291. Groove; 292. Sealing ring; 293. Trench; 294. Air inlet; 295. Third solenoid valve; 296. Fifth air pipe; 297. Sixth air pipe; 3. Air pressure sensor; 31. Hydraulic sensor. Detailed Implementation
[0016] The technical solution of this application will be further described in detail below with reference to the accompanying drawings and specific embodiments.
[0017] The components of the embodiments of this application described and shown in the accompanying drawings can be arranged and designed in a variety of different configurations. Therefore, the following detailed description of the embodiments of this application provided in the drawings is not intended to limit the scope of the claimed application, but merely to illustrate selected embodiments of the application.
[0018] Based on the embodiments in this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0019] In the description of this application, it should be noted that the terms "upper," "lower," "inner," "outer," "front end," "rear end," "both ends," "one end," and "the other end," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the present invention 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 the present invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.
[0020] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" 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 between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0021] like Figures 1 to 7 As shown, the present invention proposes an electric spindle with a composite stator, comprising a shaft body 1, a stator 11 fixedly installed inside the shaft body 1, and a rotor 12 rotatably installed inside the shaft body 1 made of composite material. The composite rotor 12 refers to a rotor 12 made of multiple materials composite structure instead of using a single silicon steel material. This design aims to overcome the limitations of the traditional rotor 12 under ultra-high speed and high heat conditions. The rotor 12 has a through hole 121 in the shaft center, and the rotor 12 can be cooled by injecting coolant into the through hole 121. The electric spindle also includes a spindle cooling component 2, which includes a connector 21, a connecting pipe 211, and a connecting seat 212, which are fixedly installed at one end of the spindle body 1 and are interconnected. A liquid delivery system for inputting high-pressure coolant into the connector 21 is installed on the outside of the spindle body 1. The liquid delivery system includes a liquid tank for storing coolant. The liquid delivery system inputs the coolant from the liquid tank into the connector 21, and then into the through hole 121 through the connecting pipe 211 and the connecting seat 212. Finally, it is sprayed out through the through hole 121, which can achieve the effect of cooling the rotor. It also includes a rotating connector that connects the connecting seat 212 to the through hole 121. The rotating connector prevents coolant from entering the spindle body 1 and ensures that the rotor 12 and the connecting seat 212 maintain a rotating connection. The rotating connector includes a fixed cover 22 fixedly installed on the connecting seat 212 and a rotating plate 23 fixedly installed at one end of the rotor 12. The rotating plate 23 and the fixed cover 22 are rotatably connected by a bearing 24, so that the rotating plate 23 and the fixed cover 22 are rotatably connected.
[0022] Furthermore, multiple first protruding rings 221 are fixedly installed on the fixed cover 22, and multiple second protruding rings 231 are fixedly installed on the rotating plate 23. A labyrinth channel 25 is formed between the first protruding rings 221 and the second protruding rings 231. The middle part of the fixed cover 22 and the rotating plate 23 is provided with an infusion chamber 251 that communicates with the labyrinth channel 25, the through hole 121 and the connecting seat 212. The coolant passing through the connecting seat 212 will enter the labyrinth channel 25 through the infusion chamber 251. The coolant inside the labyrinth channel 25 will flow into the labyrinth under the action of hydraulic pressure. The fluid flows along the edge of the labyrinth 25, and the labyrinthine design of the labyrinthine channel 25 greatly increases the resistance to fluid flow into or out of the annular cavity. The fixed cover 22 contains an air chamber 252 communicating with the labyrinthine channel 25. The air chamber 252 has multiple air inlets 253 arranged in a circular array and an exhaust outlet 254. By continuously inputting high-pressure gas into the air inlets 253, gas can enter the labyrinthine channel 25, making the air pressure inside the labyrinthine channel 25 greater than the hydraulic pressure inside the labyrinthine channel 25, thus preventing liquid from flowing through the labyrinthine channel. The labyrinth channel 25 leaks. The fixed cover 22 is equipped with a drain assembly 27 for discharging the gas-liquid mixture. The drain assembly 27 includes a drain connector 271 that communicates with the labyrinth channel 25. It should be noted that the labyrinth channel is a dead zone where the gas-liquid mixture accumulates. Regularly draining it can directly remove this part of the inferior liquid that has been severely mixed with gas, preventing it from being re-entered into the through hole 121. After the liquid in this area is drained, the relatively pure coolant from the main circulation will refill the labyrinth channel 25 under the action of pressure difference, thereby periodically refreshing the buffer between the rotor 12 and the outside world and maintaining the purity and effectiveness of this barrier. This is to prevent the continuous injection of high-pressure gas into the sealing cavity. Some of the gas dissolves into the coolant under high pressure or is directly entrained into the coolant return flow in the form of tiny bubbles, avoiding the coolant from containing too many bubbles and preventing a sharp drop in cooling efficiency. Since the thermal conductivity of bubbles is much lower than that of metal and liquid, bubbles adhering to the surface of the tool and workpiece will form a heat insulation layer, which seriously hinders the transfer of heat, thereby preventing the tool temperature from rising abnormally and aggravating wear.
[0023] like Figure 3 , Figure 4 and Figure 9As shown, in this embodiment, a first solenoid valve 255 is fixedly installed on the outside of the shaft 1. One end of the first solenoid valve 255 is connected to multiple air inlet connectors 253 through a first air pipe 257. The other end of the first solenoid valve 255 is fixedly installed with a second air pipe 259. The other end of the second air pipe 259 is connected to an air pump system. High-pressure gas is input into the second air pipe 259 through the air pump system. By controlling the opening and closing of the first solenoid valve 255, it is possible to control whether the high-pressure gas can enter the first air pipe 257. Due to the presence of the bearing 24, the air chamber 252 cannot be completely sealed. Therefore, it is necessary to continuously input gas into the air chamber 252. By controlling the first solenoid valve 255, the air pressure inside the labyrinth channel 25 can be indirectly controlled. When the exhaust connector 254 is opened, the gas inside the air chamber 252 will leak, which will reduce the air pressure inside the labyrinth channel 25. This allows control of the air pressure inside the labyrinth channel 25, thus achieving air sealing of the coolant.
[0024] Furthermore, a second solenoid valve 256 is fixedly installed on the outer side of the shaft 1. One end of the second solenoid valve 256 is connected to the exhaust connector 254 through a third air pipe 258, and the other end of the second solenoid valve 256 is fixedly installed with a fourth air pipe 2510. The other end of the fourth air pipe 2510 is fixedly installed with a silencer. By controlling the opening and closing of the second solenoid valve 256, the open and closed state of the exhaust connector 254 can be controlled, thereby flexibly reducing the air pressure in the labyrinth passage 25. The shaft 1 is provided with a pressure reducing hole 28, which is connected to the inside of the shaft 1 and located on one side of the rotating plate 23. The gas passing through the gap between the fixed cover 22 and the rotating plate 23 will be discharged through the pressure reducing hole 28 to prevent the air pressure inside the shaft 1 from rising abnormally.
[0025] like Figure 3 , Figure 4 and Figure 9 As shown, in this embodiment, the drain assembly 27 also includes an electrically controlled valve 272 fixedly installed on the outside of the shaft 1. The electrically controlled valve 272 is connected to the drain connector 271 through a first drain pipe 273. The other end of the electrically controlled valve 272 is fixedly installed with a second drain pipe 274. When the electrically controlled valve 272 is opened, the gas-liquid mixture inside the labyrinth channel 25 has a discharge port. At this time, under the action of air pressure and hydraulic pressure, the gas-liquid mixture can be discharged through the drain connector 271. One end of the second drain pipe 274 is connected to a degassing device. The degassing device is connected to the liquid tank. After the discharged gas-liquid mixture is degassed by the degassing device, it can enter the liquid tank for recirculation. After one drainage cycle is completed, the vent connector 254 needs to be opened to reduce the air pressure inside the labyrinth channel 25. At this time, the air pressure will be less than the hydraulic pressure, allowing the coolant to refill the labyrinth channel 25. Then, the vent connector 254 is closed to make the air pressure greater than or equal to the hydraulic pressure, preventing coolant leakage.
[0026] like Figure 8 As shown, in this embodiment, a liquid level detection component 26 is installed inside the fixed cover 22. The liquid level detection component 26 detects the position of the coolant inside the labyrinth channel 25. Due to the influence of hydraulic and air pressure inside the labyrinth channel 25 and its labyrinth shape, the structure is complex and it is impossible to accurately detect the liquid level. Therefore, it is impossible to determine whether the liquid level is about to overflow the labyrinth channel 25, making it inconvenient to accurately control the liquid level. The liquid level detection component 26 includes multiple sets of conductors fixedly installed on the first convex ring 221. Each set of conductors includes two conductive contacts 261. A power supply 262 and a signal device 263 are installed inside the shaft 1. One end of power supply 262 is connected to one of the conductive contacts 261 via a first wire 264, and the other end of power supply 262 is connected to signal device 263 via a second wire 265. Signal device 263 is connected to another conductive contact 261 via a third wire 266. Since gas does not conduct electricity in the working environment, while coolant does conduct electricity, when the liquid comes into contact with a set of conductors at the same time, the circuit between the two conductive contacts 261 is connected, making the circuit continuous. At this time, signal device 263 is energized, and the system controller will receive the signal from signal device 263, thus determining the liquid position inside the maze passage 25.
[0027] As one implementation method, such as Figure 3 and Figure 9 As shown, the electric spindle in this embodiment also includes an imbalance sealing assembly 29 installed inside the fixed cover 22. The imbalance sealing assembly 29 includes a groove 291 provided inside the fixed cover 22 and a sealing ring 292 slidably installed in the groove 291. The rotating plate 23 is provided with a groove 293 for accommodating the sealing ring 292. The fixed cover 22 is provided with an air supply hole 294 communicating with the groove 291. A third solenoid valve 295 is fixedly installed on the outside of the shaft body 1. The third solenoid valve 295 is connected to the air supply hole 294 through a fifth air pipe 296. The other end of the third solenoid valve 295 is connected to a sixth air pipe 296. Pipe 297 is connected to the air pump system. When the air pressure inside the labyrinth channel 25 is unbalanced, to prevent coolant from entering the shaft 1, high-pressure gas can be introduced into the groove 291 by opening the third solenoid valve 295. Under the action of the high-pressure gas, the sealing ring 292 will be pushed to move, so that the sealing ring 292 enters the groove 293, which can seal the space between the fixed cover 22 and the rotating plate 23 to prevent coolant from continuing to overflow. In combination with the liquid level detection component 26, when the liquid level quickly exceeds the safe position, the imbalance sealing component 29 can be automatically activated by the control system.
[0028] like Figures 3 to 4As shown, in this embodiment, a pressure sensor 3 connected to an air chamber 252 is fixedly installed on the fixed cover 22. The pressure sensor 3 detects the air pressure inside the maze channel 25. A hydraulic sensor 31 is fixedly installed on the fixed cover 22 to check the hydraulic pressure inside the maze channel 25. The hydraulic sensor 31 detects the hydraulic pressure inside the maze channel 25, and the air pressure and hydraulic pressure inside the sealed channel can be accurately balanced and adjusted.
[0029] As one implementation method, such as Figures 3 to 9 As shown, the electric spindle also includes a control system. The control system controls the pressure difference between the air and hydraulic pressure within the labyrinth channel 25 by controlling the opening and closing of the air inlet 253, exhaust 254, and drain 271. The control system receives real-time air and hydraulic pressure data detected by the air pressure sensor 3 and hydraulic sensor 31 mounted on the fixed cover 22, and combines this with the liquid level signal fed back by the liquid level detection component 26 to make a comprehensive judgment and decision. When the system determines that a seal needs to be maintained, the control system opens the first solenoid valve 255 and closes the second solenoid valve 256 and the electrically controlled valve 272, allowing high-pressure gas supplied by the air pump system to continuously enter the air chamber 252 through the second air pipe 259, the first solenoid valve 255, the first air pipe 257, and multiple air inlets 253, ultimately filling the labyrinth channel 25 to ensure that its internal air pressure is always slightly higher than the hydraulic pressure, forming an effective air seal and preventing coolant leakage. When the system determines that the gas-liquid mixture accumulated in the labyrinth channel 25 needs to be discharged, the control system... First, the second solenoid valve 256 is opened, and some gas is released through the third air pipe 258 and exhaust connector 254 to reduce the gas pressure in the cavity. Then, the electronically controlled valve 272 is opened, so that the gas-liquid mixture is discharged to the degassing device through the drain connector 271, the first drain pipe 273, the electronically controlled valve 272 and the second drain pipe 274 under the action of pressure difference. The degassed coolant flows back to the liquid tank for recycling. After the drainage is completed, the control system closes the electronically controlled valve 272 and the second solenoid valve 256, and readjusts the opening of the first solenoid valve 255 to restore the gas-liquid pressure balance in the labyrinth channel 25. If the liquid level detection component 26 detects an abnormal increase in liquid level or the pressure sensor 3 detects a pressure imbalance, the control system will immediately activate the third solenoid valve 295 to fill the groove 291 of the imbalance sealing component 29 through the fifth air pipe 296 and the air outlet 294, pushing the sealing ring 292 into the groove 293 of the rotating plate 23 to achieve an emergency mechanical seal and prevent coolant from leaking into the shaft 1.
[0030] In this embodiment, the rotor 12, made of composite materials, improves its performance under high-speed and high-heat conditions. A shaft cooling technology is introduced by providing a through-hole 121 in the rotor shaft. Coolant is delivered from an external fluid supply system via connector 21, connecting pipe 211, and connecting seat 212. It then enters the through-hole 121 of the rotor 12 through a rotating connector formed by a fixed cover 22 and a rotating plate 23 rotatably connected by a bearing 24, and a fluid supply chamber 251 located in the middle, achieving internal cooling of the rotor. The core seal is achieved through the first convex ring 221 on the fixed cover 22 and the second convex ring 231 on the rotating plate 23. The interlocking labyrinth channel 25 achieves non-contact sealing, and by introducing controllable high-pressure gas into the air chamber 252, a pressure barrier higher than hydraulic pressure is established within the labyrinth channel 25, effectively preventing coolant leakage along the rotating interface. The system dynamically adjusts and maintains the gas-liquid pressure balance by integrating gas and hydraulic sensors, liquid level detection, and multiple solenoid valve control. It also has the function of periodically and automatically discharging the gas-liquid mixture in the labyrinth channel to refresh the coolant quality. At the same time, an imbalance sealing component 29 is provided as an emergency mechanical seal, thereby comprehensively ensuring the sealing reliability, cooling efficiency, and long service life of the electric spindle under ultra-high-speed operation.
[0031] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. An electric spindle with a composite stator, comprising a shaft body (1), a stator (11) fixedly installed inside the shaft body (1), and a rotor (12) made of composite material rotatably installed inside the shaft body (1), wherein the rotor (12) has a through hole (121) at its shaft center, characterized in that, Also include: The shaft cooling component (2) includes a joint (21) fixedly installed at one end of the shaft body (1) and communicated with each other, a connecting pipe (211) and a connecting seat (212), further comprising a rotating connecting head for communicating the connecting seat (212) with the through hole (121), the rotating connecting head comprises a fixed cover (22) fixedly installed on the connecting seat (212), a rotating plate (23) fixedly installed at one end of the rotor (12), and the rotating plate (23) and the fixed cover (22) are rotatably connected by a bearing (24); A plurality of first convex rings (221) are fixedly installed on the fixed cover (22), a plurality of second convex rings (231) are fixedly installed on the rotating plate (23), the first convex ring (221) and the second convex ring (231) form a labyrinth passage (25), the middle part of the fixed cover (22) is provided with a liquid delivery chamber (251) communicated with the labyrinth passage (25), the through hole (121) and the connecting seat (212), and a gas cavity (252) communicated with the labyrinth passage (25) is arranged in the liquid delivery chamber (251), a plurality of gas inlet joints (253) are circumferentially arranged on the gas cavity (252), and an exhaust joint (254) is arranged, the fixed cover (22) is provided with a liquid discharge assembly (27) for discharging gas-liquid mixture, and the liquid discharge assembly (27) comprises a liquid discharge joint (271) communicated with the labyrinth passage (25); The control system controls the pressure difference between the gas pressure and the liquid pressure in the labyrinth passage (25) by controlling the opening and closing of the gas inlet joint (253), the exhaust joint (254) and the liquid discharge joint (271).
2. The electrospindle of claim 1, characterized in that, A first electromagnetic valve (255) is fixedly installed on the outside of the shaft body (1), one end of the first electromagnetic valve (255) is communicated with a plurality of the gas inlet joints (253) through a first gas pipe (257), the other end of the first electromagnetic valve (255) is fixedly installed with a second gas pipe (259), and the other end of the second gas pipe (259) is connected with a gas pump system.
3. The electrospindle of claim 2, characterized in that, A second electromagnetic valve (256) is fixedly installed on the outside of the shaft body (1), one end of the second electromagnetic valve (256) is communicated with the exhaust joint (254) through a third gas pipe (258), the other end of the second electromagnetic valve (256) is fixedly installed with a fourth gas pipe (2510), and the other end of the fourth gas pipe (2510) is fixedly installed with a silencer.
4. The electrospindle of claim 3, characterized in that, The liquid discharge assembly (27) further comprises an electric control valve (272) fixedly installed on the outside of the shaft body (1), the electric control valve (272) is communicated with the liquid discharge joint (271) through a first liquid discharge pipe (273), and the other end of the electric control valve (272) is fixedly installed with a second liquid discharge pipe (274).
5. The electrospindle of claim 4, characterized in that, A liquid delivery system for inputting high-pressure cooling liquid into the joint (21) is installed on the outside of the shaft body (1), the liquid delivery system comprises a liquid tank for storing cooling liquid, one end of the second liquid discharge pipe (274) is connected with a degassing device, and the degassing device is communicated with the liquid tank.
6. The electrospindle of claim 5, characterized in that, The shaft body (1) is provided with a pressure relief hole (28) which is in communication with the inside of the shaft body (1) and located at one side of the rotating plate (23).
7. The electrospindle of claim 6, characterized in that, The fixed cover (22) is provided with a liquid level detection assembly (26) which detects the position of the cooling liquid inside the labyrinth passage (25).
8. The electrospindle of claim 7, characterized in that, The liquid level detection assembly (26) comprises a plurality of groups of conductive bodies fixedly installed on the first convex ring (221), one group of the conductive bodies comprises two conductive contacts (261), the shaft body (1) is provided with a power supply (262) and a signal indicator (263), one end of the power supply (262) is connected with one of the conductive contacts (261) through a first lead wire (264), the other end of the power supply (262) is connected with the signal indicator (263) through a second lead wire (265), and the signal indicator (263) is connected with the other conductive contact (261) through a third lead wire (266).
9. The electrospindle of claim 8, characterized in that, The fixed cover (22) is provided with an unbalance blocking assembly (29), the unbalance blocking assembly (29) comprises a groove (291) arranged inside the fixed cover (22) and a sealing ring (292) slidingly installed in the groove (291), the rotating plate (23) is provided with a groove (293) for accommodating the sealing ring (292), the fixed cover (22) is provided with a gas conveying hole (294) in communication with the groove (291), a third electromagnetic valve (295) is fixedly installed outside the shaft body (1), the third electromagnetic valve (295) and the gas conveying hole (294) are in communication through a fifth gas pipe (296), and the other end of the third electromagnetic valve (295) is in communication with a gas pump system through a sixth gas pipe (297).
10. The electrospindle of claim 9, characterized in that, The fixed cover (22) is fixedly provided with a gas pressure sensor (3) in communication with a gas cavity (252), and the fixed cover (22) is fixedly provided with a hydraulic pressure sensor (31) for checking the hydraulic pressure in the labyrinth passage (25).