High-precision leakage-free grader based on two-way air-tight seal structure

Abstract

The invention discloses a high-precision leakage-free grader based on a two-way air-tight seal structure, and relates to the technical field of superfine powder separation equipment, the high-precision leakage-free grader comprises a shell, a bearing cavity and a grading cavity are formed in the shell, a grading rotor is arranged in the grading cavity, the grading rotor is coaxially and fixedly connected with a main shaft, the main shaft is in transmission connection with a driving part, and the driving part is in transmission connection with the bearing cavity. A sealing piece is arranged on the outer side wall of the main shaft and comprises a shell, a plurality of sealed cabins are formed in the shell, a plurality of adjusting plates made of memory metal materials are arranged on the side walls of the sealed cabins, a plurality of carbon rings are arranged in the sealed cabins, a plurality of spherical protrusions are arranged on the outer side walls of the carbon rings, and the spherical protrusions are arranged on the outer side walls of the carbon rings. The carbon ring comprises an attaching section and a redundant section, the redundant section and the attaching section are each provided with an elastic piece, the elastic pieces are fixedly connected with the side wall of the sealed cabin, the side wall of the sealed cabin is provided with a plurality of nozzles, and the sealed cabin is communicated with a chip collecting groove and used for reducing the probability that the carbon ring is damaged in the machining process.

Description

Technical Field

[0001] The present invention relates to the technical field of ultrafine powder sorting equipment, and in particular to a high-precision leak-free classifier based on a bidirectional air-sealed structure. Background Art

[0002] In the graded purification of metal powders (such as titanium alloys, high-temperature alloys, and powders specifically for additive manufacturing), maintaining an ultra-low oxygen environment within the process chamber is a core requirement for ensuring safe production and product quality. Trace oxygen infiltration can trigger metal dust explosions or lead to surface oxidation failure of the powder. Currently, the industry generally uses multi-layer skeleton oil seals (made of rubber or polytetrafluoroethylene) for dynamic sealing of rotating shaft ends. This technology suffers from systemic flaws: When shaft speeds exceed 3000 rpm, the temperature of the oil seal friction interface can rise above 120°C, causing the seal material to soften and deform, rapidly failing. Rubber material aging at high temperatures produces debris that directly contaminates high-value powder materials. Seal components require downtime and replacement every 500-800 hours of operation, significantly reducing equipment utilization. Most critically, traditional structures cannot effectively block both external air infiltration (causing excessive oxygen levels) and the escape of internal inert shielding gases (such as nitrogen and argon), resulting in skyrocketing operating costs. These technical bottlenecks severely restrict the efficiency and safety of high-end metal powder manufacturing.

[0003] Bidirectional air-sealing technology solves this problem by innovating sealing principles. This technology constructs a precise annular air chamber at the end of the classifier's rotating shaft. Combined with carbon ring sealing technology, it continuously introduces compressed air at a pressure 0.1-0.3 MPa higher than that of the process chamber. By precisely controlling the gas flow and pressure, a stable, centripetal, high-speed airflow barrier is formed across the shaft gap. This airflow barrier provides a bidirectional seal: effectively blocking ambient air from penetrating the process chamber from the inside and preventing the inert shielding gas from leaking outward from the process chamber.

[0004] However, in actual application, as the processing progresses, the temperature inside the air cavity rises due to friction, the carbon ring expands due to heat, and the inner diameter and elastic modulus of the carbon ring increase. During the swing or displacement of the carbon ring, the carbon ring is more likely to collide with the side wall of the air cavity, and it is more likely to cause damage to the carbon ring due to collision, which eventually causes seal failure. Summary of the Invention

[0005] The present invention aims to provide a high-precision leak-free classifier based on a bidirectional airtight structure to solve the above problems.

[0006] The present invention is achieved through the following technical solutions: The application discloses a high-precision leak-free classifier based on a bidirectional air-tight structure, which comprises a shell, a bearing cavity and a classification cavity are arranged in the shell, a classification rotor is arranged in the classification cavity, the classification rotor is coaxially fixedly connected with a main shaft, the main shaft is drivingly connected with a driving piece, the classification rotor is used for classifying particles, the driving piece is used for driving the main shaft to rotate, a sealing piece is arranged on the outer side wall of the main shaft, the sealing piece is used for preventing the classification cavity from being communicated with the bearing cavity, the sealing piece comprises an outer shell, the outer shell is sleeved on the main shaft, a plurality of sealing cabins are arranged in the outer shell, a plurality of adjusting plates made of memory metal are arranged on the side walls of the sealing cabins, the adjusting plates are used for changing the shapes of the sealing cabins, a plurality of carbon rings are arranged in the sealing cabins, a plurality of convex protrusions in spherical shapes are arranged on the outer side walls of the carbon rings, the carbon ring comprises a fitting section and a redundant section, the carbon ring is fitted with the side wall of the main shaft through the fitting section, the projections of the fitting sections of the carbon rings arranged in the same sealing cabin on a horizontal plane are equal in length to the circumference of the main shaft, elastic pieces are arranged on the fitting sections and the redundant sections, the elastic pieces are fixedly connected with the side walls of the sealing cabins, a plurality of nozzles are arranged on the side walls of the sealing cabins, the nozzles are used for pumping pressurized gas into the sealing cabins, the sealing cabins are communicated with a scrap collecting groove, and the scrap collecting groove is used for collecting graphite scraps generated by the carbon rings.

[0007] Compared with the prior art, the application has the following advantages and beneficial effects: The volume of the sealing cabin can change along with the change of the temperature of the sealing cabin through the design of the adjusting plate, compared with the mode that the sealing cabin keeps the limiting ability of the position of the carbon ring constant in the prior art, the carbon ring can be clamped by the side wall of the sealing cabin when the inner side wall of the carbon ring is fitted with the main shaft under normal temperature, so that the carbon ring is prevented from swinging and colliding with the main shaft and causing damage to the main shaft, and the inner side wall of the sealing cabin can still limit the position of the carbon ring under high temperature, so that the carbon ring is prevented from being damaged, and the design of the convex protrusions is further adopted in the application, so that the inner side wall of the carbon ring slightly separates from the main shaft after the carbon ring expands under high temperature, the carbon ring swings back and forth under the action of the kinetic energy transmitted to the carbon ring from the outside, the carbon ring guides the graphite scraps around the carbon ring, the probability that the graphite scraps adhere to the side wall of the carbon ring or the sealing cabin is reduced, and the influence of the graphite scraps on the subsequent work of the carbon ring is reduced.

[0008] Further, the application further comprises a control system, the control system is used for collecting the temperature field information of the outer shell, acquiring the distribution of the carbon ring in the sealing cabin according to the temperature field information, and driving the movement of the carbon ring by controlling the opening and closing of each nozzle according to the distribution of the carbon ring.

[0009] Beneficial effects: Through the collection of the shell temperature field information, the distribution state of the carbon ring in the sealed cabin is judged by using the temperature field information, whether the carbon ring vibrates or displaces is judged according to the change of the carbon ring distribution state, compared with the prior art, the process of data collection of the present scheme does not produce negative effects on the work of the sealing element, and the carbon ring stability can be continuously monitored, so that the sealing failure of the carbon ring due to vibration, displacement or excessive temperature and other factors can be effectively avoided.

[0010] Further, the elastic member is a rectangular cross-section spring, and the material of the spring is metal.

[0011] Beneficial effects: In the present scheme, the spring with a rectangular cross-section is used as the elastic member, compared with other forms of carbon rings with the same outer diameter, the rectangular cross-section carbon ring can withstand greater load, effectively avoiding the failure of the elastic member during the working process of the carbon ring, thereby causing the sealing failure of the carbon ring, and compared with the disc spring, the spring used in the present scheme can deform in the axial direction of the main shaft, so that the carbon ring can still be damped during the axial movement or swing of the carbon ring.

[0012] At the same time, the spring made of metal material uses the good thermal conductivity of metal to transfer the heat generated by the carbon ring to the shell, thereby achieving the cooling of the carbon ring and avoiding the failure of the carbon ring caused by high temperature.

[0013] Further, the inner side wall of the carbon ring is provided with a shaft sleeve, and the shaft sleeve is in interference fit with the main shaft.

[0014] Beneficial effects: The design of the shaft sleeve can avoid excessive friction between the carbon ring and the main shaft, causing wear of the main shaft and resulting in leakage of the sealing element, and can also compensate for part of the deformation caused by thermal expansion of the main shaft to avoid the main shaft being stuck with the sealing element after thermal expansion.

[0015] Further, the housing is also provided with a cooling assembly, the cooling assembly is used to adjust the temperature of the gas at the input end of the nozzle, and the control system is also used to judge the temperature distribution in each sealed cabin according to the temperature field information, and control the opening and closing of the nozzle and the working of the cooling assembly according to the temperature distribution in the sealed cabin.

[0016] Beneficial effects: In the present scheme, compared with the prior art, the temperature of the gas output by the nozzle can be adjusted in real time to avoid the rupture of the carbon ring due to sudden heating and sudden cooling, and the carbon ring can also be cooled in time to further avoid the failure of the carbon ring caused by high temperature.

[0017] Further, the projections of the abutting sections of the carbon rings installed in the same sealed cabin on the same plane do not coincide.

[0018] Beneficial Effects: Compared to existing technologies, this solution can prevent the complete contact of the bonding sections that may occur when the carbon rings collide with each other during vibration or displacement, which may cause damage to the bonding sections and lead to carbon ring failure. This effectively improves the stability of the seal.

[0019] Furthermore, the sidewall of the carbon ring installed in the same sealed cabin is not parallel to the spray angle of the nozzle.

[0020] Beneficial effect: Compared with the design of using a nozzle with a spray angle parallel to the side wall of the carbon ring, this solution can avoid the situation where the gas ejected from the nozzle can only push the carbon ring to move radially but cannot push the carbon ring to move axially, thereby making it impossible to adjust the position angle of the carbon ring. At the same time, it can also avoid excessive radial movement of the carbon ring during the operation of the nozzle, causing the carbon ring to press on the main shaft or detach from the main shaft, thereby affecting the effect of the carbon ring.

[0021] Furthermore, a gasket is provided between each of the carbon rings and the adjacent carbon rings, and each of the gaskets is made of elastic material.

[0022] Beneficial effects: In this solution, the design of the liner can buffer the collision between the carbon ring and the adjacent carbon ring, further avoiding the complete failure of the carbon ring in the collision. At the same time, the design of the liner can also achieve damping of the carbon ring through its own phase change, further absorbing the kinetic energy of the carbon ring.

[0023] Furthermore, the control system is also used to collect distance information between the inner wall of the carbon ring and the main shaft, and to determine whether the carbon ring vibrates based on the distance information, and to control the operation of the nozzle when the carbon ring vibrates.

[0024] Beneficial effect: This solution determines whether the carbon ring is in the appropriate position by obtaining the distance information between the carbon ring and the outer wall of the main shaft, and supplements the carbon ring position obtained through the temperature field based on the distance information, thereby improving the accuracy of the obtained carbon ring position and avoiding system misjudgment or omission.

[0025] Furthermore, several windows are provided on the shell, and the control system transmits ultrasonic waves into the shell, receives ultrasonic waves reflected by the shell, and obtains the reflection time and amplitude of the transmitted ultrasonic waves, and obtains distance information based on the reflection time and amplitude. When the amplitude is less than the set minimum amplitude, when the reflection time is less than the set time, the distance information is zero, and the carbon ring is stable, and the working state of the nozzle is not adjusted. When the reflection time is greater than the set time, the distance information is greater than zero, and the carbon ring moves, and the nozzle at the corresponding position is controlled to work and adjust the position of the carbon ring. When the amplitude is greater than the set minimum amplitude, the carbon ring vibrates or debris appears on the carbon ring, and the nozzle is controlled to increase the working power.

[0026] Beneficial effect: in the scheme, the ultrasonic wave is emitted to the shell, the displacement of the carbon ring and the existence of the graphite debris in the sealed cabin are determined by the reflection time and amplitude of the reflected ultrasonic wave, and when the graphite debris appears or the carbon ring is displaced, the graphite debris is expelled and the carbon ring is adjusted in time, so as to reduce the time of the graphite debris staying in the sealed cabin and reduce the damage of the graphite debris to the carbon ring. BRIEF DESCRIPTION OF DRAWINGS

[0027] The drawings described herein are used to provide further understanding of the embodiments of the present application, constitute a part of the present application, and do not constitute a limitation on the embodiments of the present application. In the drawings: Figure 1 It is a structural schematic diagram of the present application; Figure 2 It is a sectional view of the sealing element in the present application; Figure 3 It is Figure 2 It is an enlarged view of A in the present application; Figure 4 It is a schematic diagram of the carbon ring part in the present application; Figure 5 It is a top view of the carbon ring part in the present application.

[0028] The symbols represented by the reference signs are: 1, shell; 11, grading cavity; 12, bearing cavity; 2, sealing element; 21, shell; 22, adjusting plate; 23, spring; 24, carbon ring; 241, redundant section; 242, fitting section; 25, gasket; 26, protrusion; 3, motor; 4, main shaft; 41, shaft sleeve; 5, grading rotor. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the present application more clear and obvious, the present application is further described in detail below in combination with the embodiments and drawings, the illustrative embodiments of the present application and the description thereof are used to explain the present application, and do not constitute a limitation on the present application. It should be noted that the present application has been in the actual research and development stage.

[0030] Example 1 As Figures 1 to 5As shown, the embodiment includes a shell 1, a bearing cavity 12 and a grading cavity 11 are arranged in the shell 1, the grading cavity 11 is provided with a grading rotor 5, the grading rotor 5 is coaxially fixedly connected with a main shaft 4, the main shaft 4 is drivingly connected with a driving member, the driving member in the scheme is a motor 3, the motor 3 is fixedly connected with the outer top wall of the shell 1 through bolts, the motor 3 is coaxially fixedly connected with the main shaft 4 through a shaft coupling, the grading rotor 5 is used for grading particles, the driving member is used for driving the main shaft 4 to rotate, the outer side wall of the main shaft 4 is provided with a sealing element 2, the sealing element 2 is used for preventing the grading cavity 11 from communicating with the bearing cavity 12, the sealing element 2 comprises an outer shell 21, the outer shell 21 is sleeved on the main shaft 4, and a plurality of sealing cabins are arranged in the outer shell 21, a plurality of adjusting plates 22 made of memory metal are welded and fixed on the side walls of the sealing cabins, in the initial state, the adjusting plates 22 located in the same sealing cabin are in a straight line, and one adjusting plate 22 is bent after reaching its threshold temperature, and the remaining adjusting plates 22 are in an arc shape and become flat after reaching their threshold temperatures, the adjusting plates 22 are used for changing the shape of the sealing cabin, a plurality of carbon rings 24 are arranged in the sealing cabin, in the embodiment, the carbon rings 24 are in an elliptical ring shape, a plurality of spherical protrusions 26 are integrally formed on the outer side walls of the carbon rings 24, a gasket 25 is arranged between the carbon ring 24 and the adjacent carbon ring 24 in the same sealing cabin, the gasket 25 is made of elastic material, an axle sleeve 41 is arranged on the inner side wall of the carbon ring 24, the axle sleeve 41 is in interference fit with the main shaft 4, the carbon ring 24 comprises a fitting section 242 and a redundant section 241, the carbon ring 24 is fitted with the side wall of the main shaft 4 through the fitting section 242, the projection of the fitting section 242 of the carbon ring 24 installed in the same sealing cabin on a horizontal plane is as long as the circumference of the main shaft 4, the projections of the fitting sections 242 of the carbon rings 24 installed in the same sealing cabin on the same plane do not coincide with each other, the redundant section 241 and the fitting section 242 are provided with elastic elements, the elastic elements are springs 23, and the materials of the springs 23 are metal, in the embodiment, the springs 23 are made of metal copper, the elastic elements are welded and fixed with the side walls of the sealing cabin, a plurality of nozzles are arranged on the side walls of the sealing cabin, the nozzles are used for pumping pressurized gas into the sealing cabin, the sealing cabin is communicated with a chip collecting groove (not shown in the figure), and the chip collecting groove is used for collecting graphite chips generated by the carbon ring 24.

[0031] The spray angles of the carbon rings 24 and the nozzles installed on the same side wall of the sealing cabin are not parallel.

[0032] The specific implementation is as follows: when the device is used, the input end and the output end of the shell 1 are respectively communicated with the upstream and downstream production lines of the classifier, and a storage tank storing appropriate pressurized inert gas is communicated with the nozzle, and then the classifier is started. During the operation of the classifier, the motor 3 drives the classification rotor 5 to rotate through the main shaft 4, so as to realize the classification of the material passing through the shell 1.

[0033] During this process, the sealing element 2 seals the connection between the main shaft 4 and the side wall of the bearing cavity 12, preventing external contaminants from entering the classification cavity 11 from the gap between the side wall of the main shaft 4 and the side wall of the bearing cavity 12, causing contamination of the material and leakage of the material, and affecting the final yield of the material.

[0034] With the rotation of the main shaft 4, the graphite crystal layer on the inner side wall of the carbon ring 24 is displaced with the movement of the main shaft 4, thereby achieving self-lubrication. At the same time, the communication between the closed classification cavity 11 and the bearing cavity 12 is greatly reduced, and the influence on the movement of the main shaft 4 is also greatly reduced. At the same time, since the carbon ring 24 has good thermal conductivity, the carbon ring 24 can quickly conduct the heat generated by the friction with the main shaft 4 to the outside, so as to avoid the influence on the main shaft 4.

[0035] Since the movement of the material in the production line mainly depends on the high-pressure inert gas flowing inside the production line, when the material moves into the classification cavity 11, the high-pressure inert gas causes the air pressure in the classification cavity 11 to rise, thereby causing the air pressure difference between the classification cavity 11 and the sealed cabin to rise. At this time, the risk of leakage rises, and the nozzle can be opened to pump pressurized inert gas into the sealed cabin through the nozzle to increase the air pressure in the sealed cabin, prevent the high-pressure gas in the classification cavity 11 from entering the sealed cabin, and cause damage to the carbon ring 24 and contamination or leakage of the material. Then in the above process, with the friction between the carbon ring 24 and the main shaft 4 and the pumping of high-pressure gas, temperature fluctuations and air pressure fluctuations occur in the sealed cabin. With the temperature fluctuations or air pressure fluctuations, due to the reasons such as deformation of the carbon ring 24 or turbulent excitation, the circular carbon ring 24 used in the traditional scheme swings or vibrates, and then collides with the sealed cabin or the main shaft 4, thereby causing damage to the carbon ring 24, which may cause subsequent sealing failure of the sealing element 2, thereby affecting the quality of the finished material.

[0036] When the temperature in the sealed cabin is at room temperature, the threshold temperature of the memory metal is not reached, and the adjusting plate 22 does not deform significantly. At this time, the side wall of the sealed cabin limits the axial movement of the carbon ring 24, so that it can only move radially. At this time, the carbon ring 24 is at the most stable temperature, and the inner side wall of the carbon ring 24 is attached to the outer side wall of the main shaft 4. The carbon ring 24 is not prone to violent swinging. At this time, the amplitude of the carbon ring 24 is small, and the kinetic energy on the carbon ring 24 is small. Therefore, even if the carbon ring 24 collides with the side wall of the sealed cabin after a slight vibration, the damage to the carbon ring 24 is small. Therefore, by limiting the movement of the carbon ring 24 through the side wall of the sealed cabin, the repeated collision between the carbon ring 24 and the side wall of the sealed cabin due to the continuous vibration of the carbon ring 24 is reduced, thereby reducing the probability of damage to the carbon ring 24. When the carbon ring 24 moves radially, the kinetic energy of the carbon ring 24 is transferred to the elastic member, so that the elastic member can realize the damping of the carbon ring 24. At the same time, as the carbon ring 24 moves radially, the carbon ring 24 rubs against the adjacent gasket 25. Since the gasket 25 is fixed on one side to the adjacent carbon ring 24, there is a gap between the other side of the gasket 25 and the adjacent carbon ring 24. When the carbon ring 24 moves radially, the carbon ring 24 rubs against the adjacent gasket 25. When rubbing, the surface layer crystal of the side wall of the carbon ring 24 is displaced to form a dynamic graphite transfer film. That is, the self-lubricating property of the carbon ring 24 is used to realize the lubrication between the carbon ring 24 and the gasket 25, thereby reducing the wear of the carbon ring 24 during radial movement.

[0037] At the same time, as the temperature in the sealed chamber rises, when it reaches the threshold temperature of the memory metal, the adjustment plate 22 is deformed. As the adjustment plate 22 is deformed, the internal volume of the sealed chamber increases. At the same time, as the temperature rises, the carbon ring 24 expands when it is heated. At the same time, due to the design of the elastic member, as the carbon ring 24 is deformed, the elastic member continues to push the fitting section of the carbon ring 24 toward the direction of the main shaft 4 to avoid the sealing failure that may be caused by the fitting section of the carbon ring 24 being separated from the main shaft 4 for a long time. Since the carbon ring 24 is elliptical, that is, the inner wall of the carbon ring 24 cannot be completely fitted with the side wall of the main shaft 4, as the internal area of ​​the sealed chamber increases, the carbon ring 24 is more likely to move. However, due to the design of the redundant section 241 during the movement, the probability of the inner wall of the carbon ring 24 colliding with the side wall of the main shaft 4 is reduced. In the above process, the kinetic energy transfer on the carbon ring 24 As for the elastic part, the elastic part converts the kinetic energy into its own elastic potential energy, thereby achieving damping of the carbon ring 24, preventing the carbon ring 24 from moving violently and affecting the overall stability of the seal 2. At the same time, as the carbon ring 24 vibrates, due to the action of the spherical protrusion 26, the protrusion 26 in contact with the side wall of the sealed cabin rolls, and the carbon ring 24 tilts at this time. Affected by the weight of the carbon ring 24, its center of gravity shifts to the vertical position, and gravity forms a restoring torque, causing the carbon ring 24 to swing back and forth. During the above process, the elastic part continuously converts the kinetic energy transmitted by the carbon ring 24 into elastic potential energy and thermal energy to achieve absorption of the kinetic energy of the carbon ring 24. At the same time, as the carbon ring 24 swings, the powder debris generated by the carbon ring 24 in the sealed cabin is guided. During the above process, the nozzle continuously pumps pressurized inert gas into the sealed cabin, and the pressurized inert gas carries the powder debris into the chip collecting trough.

[0038] Compared with the prior art that only uses pressurized gas to drive the powder debris in the sealed cabin, the convex 26 enables the carbon ring 24 to swing back and forth during the movement of the carbon ring 24, and the swinging of the carbon ring 24 loosens the powder debris, thereby improving the cleaning efficiency of the pressurized gas. At the same time, the swinging of the carbon ring 24 can prevent the powder debris from being stuck between the carbon ring 24 and the carbon ring 24 or between the carbon ring 24 and the side wall of the sealed cabin, so that the uneven stress on the carbon ring 24 does not cause high-frequency vibration or thermal runaway during subsequent work, thereby causing the sealing failure of the seal 2 and affecting the processing of the metal powder. Compared with the prior art of pumping constant pressure gas into the seal 2, the present scheme can reduce the internal pressure change of the sealed cabin due to temperature change, causing the carbon ring 24 to lose stability, or the pressure difference between the inside and outside of the sealed cabin changes during production, causing the carbon ring 24 to wear out or the carbon ring 24 to separate from the main shaft 4. At the same time, by designing the elliptical carbon ring 24, the abutting segments 242 located at different positions on the main shaft 4 are used to destroy the smooth flow path of the gas along the main shaft 4, so as to gradually buffer the kinetic energy of the leaked gas. During this process, the kinetic energy of the gas is converted into heat energy, and the pressure of the gas gradually decreases, so that the pressure difference between the leaked gas and the pressure at the other end of the seal 2 decreases, making it more difficult for the leaked gas to overcome the resistance and pass through the seal 2, thereby reducing the probability of gas penetration. With the increase of the carbon ring 24 and the sealed cabin, the probability of gas penetration gradually decreases, and finally only a small amount of leaked gas can pass through the seal 2 into the bearing cavity 12, achieving effective sealing. That is, by increasing the leakage path, the particle leakage in the grading cavity 11 is reduced, and the gas in the bearing cavity 12 is prevented from entering the grading cavity 11. Compared with the prior art, after the carbon ring 24 is heated and expanded, the abutting segments 242 of the carbon ring 24 can be kept in contact with the main shaft 4 by the elastic member and the pressurized gas sprayed by the nozzle, thereby greatly reducing the sealing failure caused by the deformation of the carbon ring 24.

[0039] Due to the properties of graphite, graphite powder is easily rubbed against each other under the action of pressurized gas, thereby generating static electricity. The charged graphite powder is adsorbed onto the elastic member or the carbon ring 24. Due to the lubricity of graphite, the graphite powder may also adhere to the carbon ring 24 after colliding with the carbon ring 24 or the main shaft 4, causing wear to the carbon ring 24 during subsequent work, thereby possibly causing sealing failure. The present scheme enables the carbon ring 24 to swing, uses inertia to improve the cleaning efficiency of the pressurized air, and makes the graphite particles more easily peel off from the carbon ring 24 and the elastic member, thereby reducing the influence of graphite powder on the work of the carbon ring 24.

[0040] Meanwhile, in the scheme, the projection of the fitting section 242 of the carbon ring 24 in the same sealed cabin does not coincide. As the device works, if the carbon ring 24 collides with the adjacent carbon ring 24 due to vibration, etc., the fitting section 242 of the carbon ring 24 in the scheme can only collide with the redundant section 241 of the adjacent carbon ring 24. Since the carbon ring 24 is in an elliptical shape, the fitting section 242 of the carbon ring 24 and the redundant section 241 of the adjacent carbon ring 24 do not completely coincide, thereby reducing the area of damage of the fitting section 242 in the collision process and reducing the probability of complete failure of the carbon ring 24 in the collision process.

[0041] In the scheme, the nozzle is arranged obliquely with the side wall of the carbon ring 24, which avoids that the pressurized gas sprayed by the nozzle acts on the carbon ring 24 in the radial direction of the carbon ring 24, thereby avoiding that the pressurized gas can only push the carbon ring 24 to move in the radial direction, but cannot drive the carbon ring 24 to move in the axial direction, thereby making it difficult to adjust the oblique angle of the carbon ring 24, and at the same time, the carbon ring 24 can be separated from the main shaft 4, which affects the normal work of the carbon ring 24.

[0042] Embodiment 2 The difference between the above embodiment and the present embodiment is that the control system is further included. In the scheme, the control system includes a controller and a plurality of infrared thermal imagers. The controller is fixedly connected to the outer side wall of the shell 1 by bolts, and the infrared imagers and the nozzles are electrically connected to the controller. The observation positions of the infrared thermal imagers are different. The infrared thermal imagers are used to collect thermal maps of the shell 21 at different angles. In other embodiments, optical fiber cable sensors or the like can be used to obtain temperature information of the shell 21 at different angles. After the controller obtains the thermal maps of the shell 21 at different angles, the temperature field information of the shell 21 can be obtained by using the data calibration formula of the thermal imager in the prior art. The distribution of the carbon ring 24 inside the sealed cabin can be obtained according to the temperature field information. The movement of the carbon ring 24 is driven by controlling the opening and closing of each nozzle.

[0043] The shell 1 further comprises a cooling assembly. In the scheme, the nozzle is communicated with the gas storage tank through a hose. The cooling assembly comprises a cooling pipe, a water pump and a water storage pool. One end of the cooling pipe is communicated with the water pump, the other end of the cooling pipe is communicated with the water storage pool, and the output end of the water pump is communicated with the water storage pool. The cooling pipe is wound inside the gas storage tank. The cooling assembly is used to adjust the temperature of the gas at the input end of the nozzle. The water pump is electrically connected to the controller. The water pump is also used to judge the temperature distribution in each sealed cabin according to the temperature field information, and to control the opening and closing of the nozzle and the working of the water pump according to the temperature distribution in the sealed cabin.

[0044] The specific implementation is as follows: during use of the scheme, the infrared thermal imager continuously acquires thermal maps of the shell 21 at different angles and constructs a temperature field of the shell 21. Since the carbon rings 24 are distributed at different positions in the sealed cabin, that is, the internal mass of the shell 21 is unevenly distributed, the thermal maps at different positions of the shell 21 at different angles show different temperatures at different positions of the shell 21. According to the different temperatures of the shell 21 at different positions at different angles, the positions of the carbon rings 24 in the shell 21 can be deduced, that is, the positions of the carbon rings 24 are basically positioned by the temperature field. When the sealed member 2 is kept stable, the carbon rings 24 remain in a relatively static state, the temperature of each position of the shell 21 in the temperature field changes little, and the change speed is slow. When the carbon rings 24 are displaced due to changes in air pressure difference or temperature, the temperature of the corresponding position of the carbon ring 24 changes rapidly. That is, when the temperature field indicates that the temperature change rate of the position corresponding to a carbon ring 24 exceeds a set value, it is determined that the carbon ring 24 is displaced. At this time, the controller controls the nozzle corresponding to the carbon ring 24 to increase or decrease the working power, so as to adjust the position of the carbon ring 24 and assist the carbon ring 24 to return to the original position.

[0045] The scheme acquires the mass distribution at different positions in the shell 21 by collecting the temperature field of the shell 21, so as to deduce the positions of the carbon rings 24. According to the speed of the change of the positions of the carbon rings 24, it is determined whether the carbon rings 24 are displaced due to changes in air pressure difference or temperature. After the carbon rings 24 are displaced, the carbon rings 24 are assisted to return to the original positions. Compared with the prior art, the scheme can convert the kinetic energy of the carbon rings 24 into heat energy and consume the heat energy, so as to avoid damage caused by continuous swinging of the carbon rings 24 and internal instability of the sealed member 2, and affect the sealing effect of the sealed member 2.

[0046] Embodiment 3 The difference from the above embodiments is that the control system is also used to collect distance information between the inner side wall of the carbon ring 24 and the main shaft 4. In other embodiments, a laser detector can be used to emit laser to the gap between the main shaft 4 and the carbon ring 24. According to the laser shielding condition, the distance information between the carbon ring 24 and the main shaft 4 is determined, and whether the carbon ring 24 vibrates is determined according to the distance information. When the distance information intermittently or continuously appears to be greater than zero, the carbon ring 24 vibrates. When the carbon ring 24 vibrates, the nozzle is controlled to work.

[0047] The shell 21 is provided with a plurality of windows, the control system further comprises an ultrasonic detector (not shown in the figure), and the ultrasonic detector used in the embodiment is an ultrasonic detector provided with a multi-probe array system, the number of probes is greater than or equal to the number of carbon rings 24 to be monitored, and the probes are uniformly arranged along the axis line of the main shaft 4. The ultrasonic detector is electrically connected with the controller, the ultrasonic detector is fixedly connected with the top wall of the bearing cavity 12 through bolts, the transmitter of the ultrasonic detector emits ultrasonic waves into the shell 21, at the same time, the receiver of the ultrasonic detector receives the ultrasonic waves reflected by the shell 21, the controller obtains the reflection time and amplitude of the emitted ultrasonic waves, and the distance information is obtained according to the reflection time and amplitude. When the amplitude is less than the set minimum amplitude and the reflection time is less than the set time, the distance information is zero, then the carbon ring 24 is stable, and the working state of the nozzle is not adjusted. When the reflection time is greater than the set time, the distance information is greater than zero, the carbon ring 24 moves, and the working state of the nozzle corresponding to the position is adjusted to adjust the position of the carbon ring 24. When the amplitude is greater than the set minimum amplitude, the carbon ring 24 vibrates or the carbon ring 24 appears debris, at this time, the working power of the nozzle is increased.

[0048] The specific implementation is as follows: when the device is used, in the working process of the device, the ultrasonic detector continuously emits ultrasonic waves into the shell 21 along the side wall of the main shaft 4 through the window. In the stable state of the carbon ring 24, the ultrasonic waves are reflected when passing through the side wall of the closest fitting section 242, at this time, the time of the ultrasonic waves back to the receiver after reflection is short. When the carbon ring 24 vibrates and moves, the ultrasonic waves can pass through the gap between the closest fitting section 242 and the main shaft 4, at this time, the time of the ultrasonic waves to the receiver after reflection changes. When the debris appears in the sealed cabin, the amplitude of the ultrasonic waves changes due to the shielding of the debris. When the size of the debris is small, the reflection area of the ultrasonic waves is small, at this time, the amplitude is large. When the debris is large (such as the carbon ring 24 is broken), the time of the debris shielding the ultrasonic waves is longer in the movement process of the debris in the sealed cabin, and then the amplitude of the ultrasonic waves is reduced, but is still greater than that in the case that the ultrasonic waves are completely emitted through the carbon ring 24.

[0049] Therefore, in the process of using the device, the state in the sealed cabin can be judged according to the reflection time and amplitude of the ultrasonic waves. While judging whether the debris exists in the sealed cabin, whether the carbon ring 24 is kept in the appropriate position can also be judged. When the debris exists in the sealed cabin or the carbon ring 24 moves, the nozzle is used to drive away the debris, and the carbon ring 24 is helped to return to the appropriate position. Compared with the prior art, the present scheme is convenient and fast, the accuracy of the obtained position of the carbon ring 24 is improved through the redundant data acquisition scheme, and the probability of misjudgment or omission is reduced.

[0050] The specific implementation methods described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above description is only a specific implementation method of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-precision, leak-free classifier based on a bidirectional air-sealed structure, comprising a housing (1), wherein a bearing cavity (12) and a classification cavity (11) are provided in the housing (1), wherein a classification rotor (5) is provided in the classification cavity (11), wherein the classification rotor (5) is coaxially fixedly connected to a main shaft (4), wherein the main shaft (4) is in transmission connection with a driving member, wherein the classification rotor (5) is used for classifying particles, wherein the driving member is used for driving the main shaft (4) to rotate, wherein a sealing member (2) is provided on an outer wall of the main shaft (4), wherein the sealing member (2) is used for preventing the classification cavity (11) from communicating with the bearing cavity (12), and wherein: The sealing member (2) comprises a shell (21), the shell (21) being sleeved on the main shaft (4), and a plurality of sealed chambers being opened in the shell (21), a plurality of adjustment plates (22) made of memory metal material being provided on the side walls of the sealed chambers, the adjustment plates (22) being used to change the shape of the sealed chambers, a plurality of carbon rings (24) being provided in the sealed chambers, the outer side walls of the carbon rings (24) being provided with a plurality of spherical protrusions (26), the carbon rings (24) comprising a fitting section (242) and a redundant section (241), the carbon rings (24) being provided with a plurality of spherical protrusions (26) on the outer side walls of the carbon rings (24), (242) is fitted with the side wall of the main shaft (4), and the projection of the fitting section (242) of the carbon ring (24) installed in the same sealed cabin on the horizontal plane is equal to the circumference of the main shaft (4), the redundant section (241) and the fitting section (242) are both provided with elastic parts, and the elastic parts are fixedly connected to the side wall of the sealed cabin. The side wall of the sealed cabin is provided with a plurality of nozzles, and the nozzles are used to pump pressurized gas into the sealed cabin. The sealed cabin is connected to a chip collecting groove, and the chip collecting groove is used to collect graphite debris generated by the carbon ring (24).

2. A high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 1, characterized in that: The invention also includes a control system, wherein the control system is used to collect temperature field information of the shell (21), and obtain the distribution of the carbon ring (24) inside the sealed cabin according to the temperature field information, and promote the movement of the carbon ring (24) by controlling the opening and closing of each nozzle according to the distribution of the carbon ring (24).

3. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 1, characterized in that: The elastic member is a spring (23) with a rectangular cross-section, and the material of the spring (23) is metal.

4. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 1, characterized in that: A shaft sleeve (41) is provided on the inner side wall of the carbon ring (24), and the shaft sleeve (41) is interference-fitted with the main shaft (4).

5. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 2, characterized in that: A cooling assembly is also provided in the housing (1), and the cooling assembly is used to adjust the temperature of the gas at the input end of the nozzle. The control system is also used to judge the temperature distribution in each of the sealed cabins based on the temperature field information, and to control the opening and closing of the nozzle and the operation of the cooling assembly based on the temperature distribution in the sealed cabin.

6. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 1, characterized in that: The projections of the fitting sections (242) of the carbon rings (24) installed in the same sealed cabin on the same plane do not overlap.

7. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 1, characterized in that: The side wall of the carbon ring (24) installed in the same sealed cabin is not parallel to the injection angle of the nozzle.

8. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 1, characterized in that: A gasket (25) is provided between each carbon ring (24) and an adjacent carbon ring (24), and each gasket (25) is made of elastic material.

9. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 2, characterized in that: The control system is also used to collect distance information between the inner wall of the carbon ring (24) and the main shaft (4), and to determine whether the carbon ring (24) vibrates based on the distance information, and to control the nozzle to operate when the carbon ring (24) vibrates.

10. The high-precision, leak-free classifier based on a bidirectional airtight structure according to claim 9, characterized in that: The shell (21) is provided with a plurality of windows. The control system transmits ultrasonic waves into the shell (21), receives ultrasonic waves reflected by the shell (21), and obtains the reflection time and amplitude of the transmitted ultrasonic waves. Distance information is obtained according to the reflection time and amplitude. When the amplitude is less than the set minimum amplitude, when the reflection time is less than the set time, the distance information is zero, and the carbon ring (24) is stable, and the working state of the nozzle is not adjusted. When the reflection time is greater than the set time, the distance information is greater than zero, and the carbon ring (24) moves, and the nozzle at the corresponding position is controlled to work and adjust the position of the carbon ring (24). When the amplitude is greater than the set minimum amplitude, the carbon ring (24) vibrates or debris appears on the carbon ring (24), and the nozzle is controlled to increase the working power.

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