Neodymium-iron-boron powder mixing drum

Abstract

The present application relates to neodymium iron boron powder stirring barrel technical field, disclose a kind of neodymium iron boron powder stirring barrel, the top of the barrel is equipped with barrel cover, the center of the barrel cover is equipped with upper jet assembly, the center of the bottom in the barrel is equipped with lower jet assembly, the cooperation of upper jet assembly and lower jet assembly is used to optimize the airflow distribution inside the barrel, to realize the uniform mixing of powder, and the jet airflow of upper jet assembly and lower jet assembly is used to form closed circulation flow field, further improve the mixing effect of powder, equipped with magnetic suspension mixing assembly in the barrel, form "paddle-air flow" double shear, force large particles to be forced to rise, can effectively overcome the defect that large particles sink to bottom in the mixing process of powder and cause uneven mixing.

Description

Technical Field

[0001] This invention relates to the field of neodymium iron boron powder mixing cylinder technology, and particularly to a neodymium iron boron powder mixing cylinder. Background Technology

[0002] Neodymium iron boron powder has attracted much attention due to its wide range of applications, but its flammable properties pose significant safety challenges. Before molding and producing neodymium iron boron magnets, it is usually necessary to use a stirring device to stir the powder required for production. Currently, the main methods for mixing neodymium iron boron powder include manually adding additives and traditional mechanical stirring methods.

[0003] However, these methods have revealed many limitations in practical applications. For example, manually adding additives can easily lead to local agglomeration of powder, making it difficult to achieve uniform dispersion. Traditional mechanical mixing methods are limited by the structure and movement of the mixer, which means that the mixing blades of the traditional mixer can only come into contact with the powder in a limited area when rotating. This means that the mixing rollers of the mixing device can only increase the intensity of local mixing and cannot fully cover all corners of the barrel. Especially when processing fine powder particles, dead corners or areas that are not fully mixed are likely to appear. These problems not only affect the mixing efficiency but may also lead to unstable performance of the final product. There is an urgent need for a more advanced multi-angle mixing solution.

[0004] Therefore, the present invention proposes a neodymium iron boron powder stirring cylinder to solve the above problems. Summary of the Invention

[0005] The purpose of this invention is to provide a neodymium iron boron powder mixing cylinder to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a neodymium iron boron powder mixing cylinder, comprising a cylinder, a cylinder cover being fitted at the top of the cylinder, an upper spraying assembly being fitted at the center of the cylinder cover, and a lower spraying assembly being fitted at the center of the bottom of the cylinder.

[0007] The upper injection assembly includes a driver fixed at the center of the cylinder cover. The output end of the driver is fixedly mounted on a rotating disk through the cylinder cover. Twelve sets of universal ball head injection valves are evenly mounted along the circumferential direction on the bottom outer edge of the rotating disk. A first air supply pipe is mounted at the center of the rotating disk. The first air supply pipe and the twelve sets of universal ball head injection valves are connected through an air supply pipe. Each set of universal ball head injection valves also includes a stepper motor fixed at the bottom of the rotating disk. The output end of the stepper motor is fixedly connected to the universal ball head injection valve.

[0008] The lower injection assembly comprises a protection cylinder fixed at the center of the bottom of the barrel, a disc type air floating bottom plate is arranged above the protection cylinder, a permanent magnet ring is fixed at the bottom of the disc type air floating bottom plate, the protection cylinder and the permanent magnet ring form a magnetic suspension structure, the outer edge of the top of the disc type air floating bottom plate is uniformly distributed with Venturi nozzles outward and at an inclination angle of 45 degrees along the circumferential direction, and the Venturi nozzles are communicated with the second gas supply pipe.

[0009] Preferably, the driver comprises a protective shell fixed at the top of the barrel cover and a rotating barrel rotatably assembled at the center of the barrel cover through a bearing, the bottom end of the rotating barrel is fixed at the top center of the rotating disc, the top end of the rotating barrel extends into the protective shell and is fixedly installed with a pinion, the outer side of the pinion is engaged and assembled with a main gear, and the top of the protective shell is provided with a servo motor fixedly connected with the main gear.

[0010] Preferably, the top of the rotating disc is integrally formed with a material blocking ring, the top of the material blocking ring is attached to the top of the inner side of the barrel cover, the barrel cover is provided with an inlet, and a gap of 3mm is reserved between the outer edge of the rotating disc and the inner side wall of the barrel cover.

[0011] Preferably, the top end of the first gas supply pipe extends out of the protective shell through the rotating barrel and the pinion, and a channel accommodating the gas conveying pipe is formed in the rotating disc.

[0012] Preferably, three groups of radial electromagnets are fixed in the protection cylinder and uniformly distributed at an angle of 120 degrees, the permanent magnet ring is matched with the three groups of radial electromagnets, the protection cylinder is defined as a "stator", and the permanent magnet ring is defined as a "rotor".

[0013] Preferably, a butterfly valve is arranged in the protection cylinder, six groups of fan-shaped air chambers are uniformly distributed in the disc type air floating bottom plate, the Venturi nozzles are communicated with the fan-shaped air chambers, the second gas supply pipe is communicated with the fan-shaped air chambers through the butterfly valve and the gas guide pipes, the number of gas guide pipes is the same as that of the fan-shaped air chambers, and a proportional valve is fixedly assembled on each group of gas guide pipes.

[0014] Preferably, a heat conducting ring is fixed on the outer side wall of the barrel, a phase change heat absorbing ring corresponding to the heat conducting ring is fixed on the inner side wall of the barrel, and the phase change heat absorbing ring is filled with paraffin-graphene.

[0015] Preferably, pressure sensors and material level sensors are fixed on the inner side wall of the barrel at upper, middle and lower positions, respectively.

[0016] Technical effects and advantages of the present application:

[0017] The application optimizes the airflow distribution in the barrel by the cooperation of the upper and lower injection assemblies, so as to realize the uniform mixing of the powder, and further improves the mixing effect of the powder by the synergistic effect of the injection airflow of the upper and lower injection assemblies, so as to promote the forced updraft of the large particles and effectively overcome the defect of uneven mixing caused by the sinking of large particles in the mixing process. BRIEF DESCRIPTION OF DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the application;

[0019] Figure 2 It is a schematic diagram of the overall structure of the application;

[0020] Figure 3 It is a schematic diagram of the overall structure of the application;

[0021] Figure 4 It is a schematic diagram of the overall structure of the application;

[0022] Figure 5 It is a schematic diagram of the overall structure of the application;

[0023] In the figure: 1, barrel; 2, barrel cover; 3, protective shell; 4, servo motor; 5, rotating cylinder; 6, pinion; 7, main gear; 8, rotating disc; 9, material blocking ring; 10, universal ball head injection valve; 11, first gas supply pipe; 12, feed inlet; 13, heat conducting ring; 14, phase change heat absorption ring; 19, protective cylinder; 20, disc type air floating bottom plate; 21, permanent magnet ring; 22, butterfly valve; 23, venturi nozzle; 24, second gas supply pipe. DETAILED DESCRIPTION

[0024] The technical solutions in the embodiments of the application will be described clearly and completely below with reference to the drawings in the embodiments of the application. Obviously, the described embodiments are only part of the embodiments of the application, not all the embodiments of the application. Based on the embodiments in the application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of protection of the application.

[0025] As Figures 1 to 5As shown, the embodiment discloses a neodymium iron boron powder stirring barrel, which comprises a barrel 1, a barrel cover 2 is arranged on the top of the barrel 1, an upper injection assembly is arranged at the center of the barrel cover 2, a lower injection assembly is arranged at the center of the bottom of the barrel 1, the cooperation of the upper injection assembly and the lower injection assembly optimizes the airflow distribution inside the barrel 1, so as to realize the uniform mixing of the powder, and the synergistic effect of the injection airflow of the upper injection assembly and the lower injection assembly forms a closed circulation flow field, which further improves the mixing effect of the powder. Meanwhile, the mixed airflow forces the large particles to be forced to rise, which can effectively overcome the defect that the large particles sink to the bottom during the mixing process, resulting in uneven mixing.

[0026] Please refer to Figures 1-5 The upper injection assembly comprises a driver fixed at the center of the barrel cover 2, the output end of the driver is fixedly arranged with a rotating disc 8 penetrating through the barrel cover 2, the bottom outer edge of the rotating disc 8 is uniformly arranged with twelve groups of universal ball head injection valves 10 in the circumferential direction, and a first gas supply pipe 11 is arranged at the center of the rotating disc 8. The first gas supply pipe 11 and the twelve groups of universal ball head injection valves 10 are communicated through a gas conveying pipe, and each group of universal ball head injection valves 10 further comprises a stepping motor fixed to the bottom of the rotating disc 8, and the output end of the stepping motor is fixedly connected with the universal ball head injection valve 10.

[0027] Please refer to Figures 2-5 The driver comprises a protection shell 3 fixed on the top of the barrel cover 2 and a rotating barrel 5 rotatably arranged at the center of the barrel cover 2, the bottom end of the rotating barrel 5 is fixed at the top center of the rotating disc 8, the top end of the rotating barrel 5 extends into the protection shell 3 and is fixedly installed with a sub gear 6, the outer side of the sub gear 6 is meshingly arranged with a main gear 7, and the top of the protection shell 3 is provided with a servo motor 4 fixedly connected with the main gear 7.

[0028] Please refer to Figure 5 The top of the rotating disc 8 is integrally provided with a material blocking ring 9, the top of the material blocking ring 9 is attached to the top of the inner side of the barrel cover 2, a feeding port 12 is formed on the barrel cover 2, and a gap of 3mm is reserved between the outer edge of the rotating disc 8 and the inner side wall of the barrel cover 2.

[0029] Please refer to Figure 5 The top end of the first gas supply pipe 11 extends out of the protection shell 3 through the rotating barrel 5 and the sub gear 6, and a channel accommodating the gas conveying pipe is formed in the rotating disc 8.

[0030] In actual use, the main gear 7 and the secondary gear 6 combine to form a planetary gear, and under the drive of the servo motor 4, the rotating disc 8 at the bottom end of the rotating cylinder 5 is driven to rotate, thereby driving the twelve groups of universal ball head injection valves 10 to rotate synchronously, blowing the powder in the inside of the cylinder 1, and when the powder is introduced into the inside of the cylinder 1 from the feeding port 12, the powder will be thrown away along the top of the rotating disc 8 to the edge of the rotating disc 8 based on the rotating centrifugal force of the rotating disc 8, and then fall into the inside of the cylinder 1 through the gap between the rotating disc 8 and the inner wall of the cylinder cover 2, and then under the blowing action of the universal ball head injection valve 10, the powder is impacted by the jet flow, avoiding the generation of a transient negative pressure zone at the feeding port 12, and the top arch can be broken, and when the inclination angle a of the universal ball head injection valve 10 is changed, the jet flow can form a spiral flow in the inside of the cylinder 1, avoiding the one-time settlement of the powder.

[0031] It is worth noting that when the stepper motor is working, the universal ball head injection valve 10 can be driven to adjust the angle, thereby adjusting the jet flow angle a, realizing continuous stepless adjustment of 0°-45°, and when the material level in the cylinder 1 is less than 20%, a=0°, at this time the jet flow is in a vertical downward state, and the arch breaking operation is completed, and when the material level is greater than 80%, a=45°, at this time the jet flow is obliquely directed to the inner wall of the cylinder 1, forming a spiral flow, through this technical means, the arch is immediately destroyed, the injection angle is optimized in real time with the material level, the smoothness rate of discharging is improved, and the first gas supply pipe 11 passes through the universal ball head injection valve 10 on the rotating cylinder 5 and the rotating disc 8 to communicate, the rotating disc 8 can realize 0-360° rotation, and the gas supply is uninterrupted.

[0032] Please refer to Figures 2-5 , the lower injection assembly includes a protective cylinder 19 fixed at the center of the bottom of the cylinder 1, a disc type air floating bottom plate 20 is arranged above the protective cylinder 19, a permanent magnet ring 21 is fixed at the bottom of the disc type air floating bottom plate 20, the protective cylinder 19 and the permanent magnet ring 21 form a magnetic suspension structure, so that the disc type air floating bottom plate 20 is suspended by 2mm through the magnetic suspension bearing, can realize 0-120rpm low-speed rotation, the top outer edge of the disc type air floating bottom plate 20 is uniformly distributed in the circumferential direction and outwardly inclined at an angle of 45°, each Venturi nozzle 23 is of a long Venturi structure, the axis is inclined outward at an angle of 45° with the normal line of the disc type air floating bottom plate 20, forming a downward and outward 45° conical jet flow, and the 45° angle can generate a negative pressure zone in the 2mm air gap below the disc type air floating bottom plate 20, and can push the powder to the cylinder wall, forming a "powder suction and upward" circulation.

[0033] And the Venturi nozzle 23 and the second gas supply pipe 24 are communicated, three groups of radial electromagnets are fixed in the protective cylinder 19 and are uniformly distributed at 120°, the permanent magnet ring 21 is matched with the three groups of radial electromagnets, the protective cylinder 19 is defined as a "stator", and the permanent magnet ring 21 is defined as a "rotor", a static bias magnetic field is formed through the permanent magnet ring 21, a basic suspension force is provided, the three groups of radial electromagnets real-time fine-tune a 2mm air gap, and a micro-gap air float backup is supplemented, and the disc-type air float bottom plate 20 can realize non-contact, low power consumption and 2mm stable suspension.

[0034] The butterfly valve 22 is arranged in the protective cylinder 19, six groups of fan-shaped air chambers are uniformly distributed in the disc-type air float bottom plate 20, the Venturi nozzle 23 and the fan-shaped air chamber are communicated, the second gas supply pipe 24 passes through the butterfly valve 22 and is communicated with the fan-shaped air chamber through a gas guide pipe, the number of the gas guide pipes is the same as that of the fan-shaped air chambers, and a proportional valve is fixedly arranged on each group of gas guide pipes.

[0035] The disc-type air float bottom plate 20 rotates and can drive the Venturi nozzle 23 to sweep the entire bottom surface, so that the powder is uniformly sucked and lifted upwards, and the proportional valve can be adjusted in real time based on the material height in the barrel 1, so as to adjust the jet flow of the Venturi nozzle 23. High-pressure air enters the Venturi nozzle 23 through the proportional valve, a high-speed jet flow is generated at the throat of the nozzle, the static pressure is suddenly reduced, a local negative pressure is formed, the negative pressure sucks the powder at the bottom of the barrel 1 into the jet flow, and the powder forms a "powder column" upwards along the airflow. The disc-type air float bottom plate 20 rotates at a low speed, so that a plurality of Venturi nozzles 23 sweep the entire bottom surface in turn, and the powder is uniformly sucked in the internal space of the barrel 1. The high-speed jet flow at the barrel cover 2 forms a downward momentum, which is combined with the powder column at the bottom to form a closed spiral circulation. Under the jetting action of the universal ball head jet valve 10, the up and down airflow ratio can be adjusted, so that the up and down airflow forms a closed spiral, the powder circulation speed is improved, the upper jet assembly and the lower jet assembly are independently designed and real-time cooperative closed loop, the mixing time is shortened, the energy consumption is reduced, and the dead angle mixing can also be realized.

[0036] When the powder is stirred, the entire stirring and mixing process is divided into five stages: feeding stage, initial mixing stage, main mixing stage, fine mixing stage and steady state stage, which are as follows:

[0037] When the mixing is in the feeding stage, the inclination angle α of the universal ball head jet valve 10 is 0°, the jet flow is vertically downward, the universal ball head jet valve 10 alternately performs the pulse mode of 0.5s opening and 0.5s closing at an air pressure of 0.6MPa, at the same time, the disc-type air float bottom plate 20 is stationary, and the six groups of proportional valves maintain an opening of 20%, so that the "arch-breaking jet flow" at the top first disperses the arch, and the bottom micro-air flow supports the bottom to prevent one-time settlement, so as to ensure that the feeding has no arching and the feeding port has no powder spraying.

[0038] When the mixing is in the initial mixing stage, the inclination angle a of the universal ball head injection valve 10 is increased from 0° to 30°, the rotating disc 8 rotates at 30 rpm, the jet flow is directed towards the inner wall of the barrel 1, at the same time, the disc type air floating bottom plate 20 rotates at 20 rpm, and the six groups of proportional valves maintain an opening of 40%, so that the top inclined jet flow plus the bottom rotating powder suction column form a primary spiral flow, which can promote the powder to be lifted from the bottom to the top, shear the powder layer, eliminate the density gradient, the concentration difference in the barrel is less than 5%, and the preliminary mixing effect of the powder is improved.

[0039] When the mixing is in the main mixing stage, the inclination angle a of the universal ball head injection valve 10 is kept at 30°, the rotating disc 8 rotates at 60 rpm, the jet flow is directed towards the inner wall of the barrel 1, at the same time, the disc type air floating bottom plate 20 rotates at 60 rpm, and the six groups of proportional valves maintain an opening of 60%, the negative pressure is controlled at-4KPa, the Euler-Lagrange two-way coupling model is used to make the particles shuttle back and forth between the two air flows, realize macro-convection + micro-diffusion double mixing, so that the upper and lower air flows form a closed "8" shape circulation, the mixing uniformity CV is reduced from 15% to 3%, and there is no dead angle.

[0040] When the mixing is in the fine mixing stage, the inclination angle a of the universal ball head injection valve 10 is changed from 30° to 10°, the rotating disc 8 rotates at 30 rpm, at the same time, the disc type air floating bottom plate 20 rotates at 30 rpm, and the six groups of proportional valves maintain an opening of 30%, the jet flow inclination angle and rotating speed are reduced, the shear rate g is reduced, the particle collision energy is reduced, the particle integrity is maintained, the shear is reduced, the powder crushing is reduced, the particle integrity rate is kept at 98%, and the temperature rise is less than 2℃.

[0041] When the mixing is in the steady state stage, the inclination angle a of the universal ball head injection valve 10 is 0°, the jet flow is vertically downward, and the universal ball head injection valve 10 alternately performs pulse mode with 0.3s opening and 0.7s closing, at the same time, the disc type air floating bottom plate 20 stops rotating, and the six groups of proportional valves maintain an opening of 10%, the top intermittent pulse forms periodic disturbance, the bottom micro-flow maintains particle suspension, and prevents secondary sedimentation; by using the vibration-suspension coupling principle, the suspension concentration gradient is kept less than 1%, and then the top intermittent jet flow maintains suspension, and the bottom only maintains micro-flow, so that sedimentation can be prevented, and unloading is waited.

[0042] When unloading, the butterfly valve is opened, the butterfly valve plate is embedded with an electromagnetic lock, which is controlled by PLC, when the mixing is in the feeding stage and the mixing stage, the electromagnetic lock is attracted, and the valve plate is closed, when the unloading starts, the electromagnetic lock is powered off, the air cylinder 2s is opened, double-layer PTFE sealing rings are added between the valve plate and the valve seat, that is, the inner ring is V-shaped and the outer ring is O-shaped, the pressure resistance is 0.6MPa, and the valve body is connected with a negative pressure dust collection cover below, the residual dust is sucked away in an instant, the on-site dust is ensured to be less than 1mg / m 3When in use, the "negative pressure curtain + electromagnetic interlock" is linked with the cover-bottom dual valves to ensure zero leakage and zero spillage throughout the feeding, mixing and discharging process.

[0043] It is worth noting that a fixed gap of 2mm is maintained between the disc-type air flotation bottom plate 20 and the bottom of the material cylinder 1, which is the magnetic levitation air gap. The powder will not leak from the outlet, relying on the following three "zero leakage" designs:

[0044] Firstly, the air gap becomes an "air cushion seal." Within the 2mm magnetic levitation gap, there is always a compensating airflow of 0.4-0.6MPa with an airflow velocity >50m / s, forming a continuous air curtain. Powder particles cannot pass through in reverse flow. The 0.4-0.6MPa continuous air curtain within the 2mm magnetic levitation gap is not an additional airflow, but rather the working medium of the "magnetic-air hybrid bearing" that the levitation system itself must provide. Therefore, the 0.4-0.6MPa compensating airflow maintains the 2mm magnetic levitation and naturally becomes a powder-sealing air curtain, eliminating the need for an additional blower.

[0045] Secondly, the discharge port is equipped with a double-layer butterfly valve. The valve plate has a double-layer PTFE sealing ring with a V-shape and an O-shape. When the valve is closed, the air curtain pressure presses the valve plate tightly, resulting in a high sealing level.

[0046] Thirdly, PLC control: when the disc-type air flotation bottom plate 20 is in a suspended state, the electromagnetic lock of the discharge port is engaged, that is, the valve plate is closed. Only when the disc-type air flotation bottom plate 20 drops to the 0.1mm standby air film or is completely de-energized, will the electromagnetic lock be de-energized and the valve be opened to discharge the material.

[0047] Please see Figures 2-4 A heat-conducting ring 13 is fixed on the outer wall of the barrel 1, and a phase change heat-absorbing ring 14 corresponding to the heat-conducting ring 13 is fixed on the inner wall of the barrel 1. The phase change heat-absorbing ring 14 is filled with paraffin-graphene. Before the powder material is introduced into the barrel 1, cold air is introduced in advance by a pulse valve to promote the early solidification of the paraffin-graphene phase change material. This facilitates the absorption of frictional heat of the material during the subsequent mixing process of the material introduced into the barrel 1, so that the temperature rise of the powder is less than 1°C and the particle breakage rate is reduced. The heat-conducting ring 13 can quickly conduct the heat on the phase change heat-absorbing ring 14 to the outside, improving the heat dissipation efficiency.

[0048] The pressure sensor and the material level sensor are respectively fixed on the upper, middle and lower positions of the inner side wall of the material cylinder 1. The pressure sensor and the material level sensor on the upper layer detect the top pressure and the material level height in the material cylinder 1, so as to find the "arch bridge" or "powder spraying", and then the inclination angle α of the universal ball head injection valve 10 at the top is increased, and the feeding speed is reduced. The pressure sensor and the material level sensor in the middle detect the middle section pressure and the density gradient in the material cylinder 1, so as to find the "density stratification", and then the rotating speed of the disc type air floating bottom plate 20 is increased, and the opening of the proportional valve is increased. The pressure sensor and the material level sensor on the lower layer detect the pressure at the bottom of the material cylinder 1 and whether the material level collapses, so as to find the "dead angle" or "hollow", and then the rotating speed of the disc type air floating bottom plate 20 is increased. The effective density of the powder can be calculated in real time through the three-layer pressure difference ΔP. The material level sensor gives the absolute material level to prevent overflow or empty warehouse. When the sensor value of a certain layer suddenly changes, the system immediately reduces the speed or stops to avoid particle breakage or equipment overload.

[0049] Finally, it should be noted that: the above only for the preferred embodiments of the present application, and not for limiting the present application, although the foregoing detailed description of the present application is made with reference to the foregoing embodiments, for those skilled in the art, it still can be modified, or part of the technical features of the equivalent replacement, within the spirit and principles of the present application, any modification, equivalent replacement, improvement, etc., should be included in the scope of protection of the present application.

Claims

1. A neodymium iron boron powder mixing cylinder, comprising a barrel (1), wherein a barrel cover (2) is fitted on the top of the barrel (1), characterized in that: The upper spraying component is installed at the center of the barrel lid (2), and the lower spraying component is installed at the center of the bottom of the material barrel (1). The upper spray assembly includes a driver fixed at the center of the barrel cover (2). The output end of the driver passes through the barrel cover (2) and is fixedly mounted on a rotating disk (8). The bottom outer edge of the rotating disk (8) is evenly equipped with twelve sets of universal ball head spray valves (10) along the circumferential direction. The center of the rotating disk (8) is equipped with a first air supply pipe (11). The first air supply pipe (11) and the twelve sets of universal ball head spray valves (10) are connected through an air supply pipe. Each set of universal ball head spray valves (10) also includes a stepper motor fixed at the bottom of the rotating disk (8). The output end of the stepper motor is fixedly connected to the universal ball head spray valve (10). The lower spray assembly includes a protective cylinder (19) fixed at the center of the bottom of the material barrel (1). A disc-shaped air flotation base plate (20) is provided above the protective cylinder (19). A permanent magnet ring (21) is fixed at the bottom of the disc-shaped air flotation base plate (20). The protective cylinder (19) and the permanent magnet ring (21) form a magnetic levitation structure. Venturi nozzles (23) facing outward and inclined at a 45° angle are evenly distributed along the circumferential direction on the top outer edge of the disc-shaped air flotation base plate (20). The Venturi nozzles (23) are connected to the second air supply pipe (24). A fixed gap of 2mm is maintained between the disc-type air flotation bottom plate (20) and the bottom of the material bucket (1), which is the magnetic levitation air gap. The powder will not leak from the fixed gap, and the air gap becomes an "air cushion seal". There is always a compensating airflow of 0.4-0.6MPa in the 2mm magnetic levitation gap. The airflow speed is >50m / s, forming a continuous air curtain. Powder particles cannot flow backward. The 0.4-0.6MPa continuous air curtain in the 2mm magnetic levitation gap is not an additional airflow, but the "magnetic-air hybrid bearing" working medium provided by the suspension system itself.

2. The neodymium iron boron powder mixing cylinder according to claim 1, characterized in that: The drive includes a protective shell (3) fixed to the top of the lid (2) and a rotating cylinder (5) rotatably mounted at the center of the lid (2) via a bearing. The bottom end of the rotating cylinder (5) is fixed at the top center of the rotating disk (8). The top end of the rotating cylinder (5) extends into the protective shell (3) and is fixedly installed with a secondary gear (6). The outer side of the secondary gear (6) is meshed with a main gear (7). The top of the protective shell (3) is provided with a servo motor (4) fixedly connected to the main gear (7).

3. The neodymium iron boron powder mixing cylinder according to claim 2, characterized in that: The top of the rotating disk (8) is integrally formed with a baffle ring (9), the top of the baffle ring (9) is attached to the top of the inner side of the barrel cover (2), the barrel cover (2) is provided with a feed inlet (12), and a 3mm gap is maintained between the outer edge of the rotating disk (8) and the inner side wall of the barrel cover (2).

4. The neodymium iron boron powder mixing cylinder according to claim 3, characterized in that: The top end of the first air supply pipe (11) extends through the rotating cylinder (5) and the auxiliary gear (6) to extend out of the protective shell (3), and the rotating disk (8) has a channel inside to accommodate the air supply pipe.

5. The neodymium iron boron powder mixing cylinder according to claim 1, characterized in that: The protective cylinder (19) is fixed with three sets of radial electromagnets evenly distributed at 120°. The permanent magnet ring (21) is adapted to the three sets of radial electromagnets. The protective cylinder (19) is defined as the "stator" and the permanent magnet ring (21) is defined as the "rotor".

6. The neodymium iron boron powder mixing cylinder according to claim 5, characterized in that: The protective cylinder (19) has a built-in butterfly valve (22). The disc-shaped air flotation base plate (20) has six sets of fan-shaped air chambers evenly distributed inside. The venturi nozzle (23) is connected to the fan-shaped air chambers. The second air supply pipe (24) passes through the butterfly valve (22) and is connected to the fan-shaped air chambers through the air guide pipe. The number of air guide pipes is the same as the number of fan-shaped air chambers. Each set of air guide pipes is fixedly equipped with a proportional valve.

7. The neodymium iron boron powder mixing cylinder according to claim 1, characterized in that: A heat-conducting ring (13) is fixed on the outer wall of the material barrel (1), and a phase change heat-absorbing ring (14) corresponding to the heat-conducting ring (13) is fixed on the inner wall of the material barrel (1), and the phase change heat-absorbing ring (14) is filled with paraffin-graphene.

8. The neodymium iron boron powder mixing cylinder according to claim 1, characterized in that: Pressure sensors and material level sensors are fixed at the upper, middle and lower positions of the inner side wall of the material barrel (1).

Images