Inlet and outlet seal vacuum crushing furnace for neodymium iron boron

Abstract

The application discloses a feeding and discharging sealed vacuum crushing furnace for neodymium iron boron, relates to the technical field of neodymium iron boron processing, and comprises a furnace body shell, the furnace body shell is connected with an external vacuum system, a driving motor is fixedly installed at the top center position of the furnace body shell, the output shaft of the driving motor is in transmission connection with one end of a driving shaft through a shaft coupling, the other end of the driving shaft extends into the furnace body shell and is connected with a crushing assembly, a connecting column is fixedly connected to the outer side of the driving shaft, and the outer side of the connecting column is provided with an intermittent feeding mechanism in the furnace body shell. The feeding and discharging sealed vacuum crushing furnace for neodymium iron boron is characterized in that when the auxiliary barrel is synchronously lowered after the sliding ring is lowered, the positions of the first discharging hole and the second discharging hole gradually correspond, at this time, the silicon dioxide in the storage barrel is uniformly discharged from the coincident holes, intermittent feeding of the neodymium iron boron particles in the crushing cavity is realized, and the particle gathering phenomenon of the neodymium iron boron caused by magnetic adsorption is effectively reduced.

Description

Technical Field

[0001] This invention relates to the field of neodymium iron boron processing technology, specifically to a sealed vacuum crushing furnace for neodymium iron boron feed and discharge. Background Technology

[0002] Neodymium iron boron (NdFeB) materials are easily oxidized in air, especially during crushing. The increased surface area accelerates oxidation, reducing the magnetic properties and potentially generating harmful oxidation products that impact operator health and the environment. Therefore, vacuum crushing furnaces are used for crushing. These sealed furnaces remove air from the interior through a vacuum system, creating a near-vacuum environment. Within this environment, mechanical crushing devices process the material. The extremely low oxygen content in a vacuum effectively prevents oxidation during crushing, preserving the material's original properties and quality.

[0003] To overcome the aforementioned deficiencies, existing technology 1 (Chinese Patent No. CN223070447U, Publication Date: 2025-07-08) discloses a hydrogenation crushing furnace, which includes a frame, a crushing furnace body, and a cooling assembly. The crushing furnace body is rotatably connected to the frame, and the cooling assembly is disposed on the frame and used to cool the crushing furnace body. The cooling assembly includes a frame, a support rod, a water spray pipe, a pressure block, and a water collection tank. The support rod is disposed on the frame and used to support the water spray pipe. The water spray pipe is detachably connected to the support rod and is located above the crushing furnace body. The water spray pipe has several nozzles along its length, each nozzle being used to spray coolant onto the crushing furnace body. The pressure block locks the water spray pipe to the support rod using fasteners. The water collection tank is located below the crushing furnace body and is used to collect the coolant sprayed from the water spray pipe. This application has the advantage of facilitating the replacement of the water spray pipe.

[0004] There is also a prior art (Chinese patent No. CN213764006U, published on 2021-07-23) of a rotary crushing furnace device, which relates to the field of magnet production equipment. It includes a support placed on the ground, on which mounting plates are symmetrically arranged. A telescopic plate for mounting a water supply pipe is provided on the mounting plate. A limiting plate for fixing the water pipe is slidably fitted on the telescopic plate. A dovetail block is integrally provided on the side of the limiting plate near the telescopic plate. A dovetail groove is opened on the telescopic plate for sliding and limiting the dovetail block. The end of the dovetail groove away from the mounting plate passes through the telescopic plate, and the end of the dovetail groove near the mounting plate does not pass through the telescopic plate. This facilitates the fixing and disassembly of the water pipe on the telescopic plate, simplifies the installation process, and improves the performance of the magnetic material.

[0005] While existing technologies have made improvements in the ease of replacing cooling components, they still face challenges in the NdFeB crushing process, such as the strong magnetism of the material itself causing particles to easily attract and aggregate after crushing, making it difficult to achieve the ideal crushing particle size, and the residual magnetism that may remain in the NdFeB material before crushing affecting the crushing effect and subsequent processing accuracy.

[0006] Therefore, we propose a sealed vacuum crusher for neodymium iron boron feed to solve the problems mentioned above. Summary of the Invention

[0007] The purpose of this invention is to provide a sealed vacuum crushing furnace for neodymium iron boron (NdFeB) feed and discharge, in order to solve the problems mentioned in the background art, such as the fact that the strong magnetism of the material itself causes the crushed particles to easily attract and aggregate, making it difficult to achieve the ideal crushing particle size, and the residual magnetism of the NdFeB material before crushing may affect the crushing effect and subsequent processing accuracy.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a sealed vacuum crushing furnace for neodymium iron boron (NdFeB) feed, comprising a furnace shell, wherein the furnace shell is connected to a vacuum pump, vacuum valve, and vacuum gauge of an external vacuum system via a flange interface, and a drive motor is fixedly installed at the top center of the furnace shell, and the output shaft of the drive motor is connected to one end of the drive shaft via a coupling, the other end of the drive shaft extends into the furnace shell and is connected to a crushing assembly, a connecting column is fixedly connected to the upper outer side of the drive shaft, and an intermittent feeding mechanism is provided between the outer side of the connecting column and the interior of the furnace shell, the intermittent feeding mechanism drives the auxiliary bucket contained therein to move position by rotating the connecting column, thereby realizing the intermittent feeding of non-magnetic powder silica, reducing the aggregation of NdFeB particles due to magnetic adsorption, and a demagnetizing mechanism is provided on the upper surface of the crushing assembly to counteract the residual magnetism of the NdFeB particles.

[0009] Preferably, the intermittent feeding mechanism includes a feeding pipe that extends through the upper part of the furnace shell, and the lower end of the feeding pipe is connected to a storage tank, which stores silica inside, and an auxiliary tank is fitted on the outside of the storage tank.

[0010] Preferably, a groove is provided on the outer side of the connecting column, and a slider is slidably connected inside the groove. A slip ring is slidably connected on the outer side of the connecting column, and the slip ring is fixedly connected to the slider. The groove is arranged in an inclined annular structure. After the connecting column rotates, the slider and the groove cooperate to drive the slip ring to move up and down.

[0011] Preferably, a slide frame is fixedly connected to the outer side of the slip ring, and the outer end of the slide frame is fixedly connected to the lower surface of the auxiliary barrel. Four sets of auxiliary barrels are symmetrically distributed about the center point of the furnace shell. A fixing rod is fixedly connected to the inside of the furnace shell, and the slide frame is slidably connected to the outside of the fixing rod.

[0012] Preferably, the auxiliary barrel has a second discharge hole on its outer side, and the storage barrel has a first discharge hole on its outer side, and the diameter of the first discharge hole is smaller than the maximum value of the diameter of the second discharge hole.

[0013] Preferably, in the initial state, the positions of the first discharge hole and the second discharge hole are staggered, the auxiliary barrel blocks the first discharge hole, and after the slip ring moves down, the positions of the first discharge hole and the second discharge hole correspond, and silicon dioxide is discharged outward from the overlapping holes.

[0014] Preferably, a connecting rod is fixedly connected to the lower surface of the carriage, and a connecting plate is fixedly connected to the lower end of the connecting rod. A pressure block is fixedly connected to the lower surface of the connecting plate, and the pressure blocks are arranged in an alternating pattern of high and low.

[0015] Preferably, the demagnetizing mechanism includes a placement groove, which is formed on the upper surface of the crushing component, and a permanent magnet is fixedly connected inside the placement groove.

[0016] Preferably, the permanent magnets are arranged in an alternating magnetic pattern, and a stainless steel cover plate is fixedly connected above the placement groove to shield the permanent magnets.

[0017] Compared with the prior art, the beneficial effects of the present invention are: (1) The furnace shell is connected to the external vacuum system, which can realize precise control and real-time monitoring of the vacuum degree inside the furnace, ensuring that the crushing process is carried out stably in a high vacuum environment, effectively isolating oxygen from contact with NdFeB materials, minimizing the occurrence of oxidation reaction, and the drive motor achieves efficient power transmission through the coupling and drive shaft, ensuring that the crushing components can obtain matching torque and speed at different crushing stages, meeting the multi-gradient crushing requirements of NdFeB materials from coarse to fine crushing; (2) During the rotation of the drive shaft, the connecting column will be rotated synchronously. Since the connecting column has an inclined annular groove on the outside, and the slider and the sliding ring are fixedly connected inside the groove, the rotation of the connecting column will be converted into the sliding of the slider along the groove, which will then drive the sliding ring to move up and down on the outside of the drive shaft. In the initial state, the positions of the first discharge hole and the second discharge hole are staggered. The auxiliary bucket effectively blocks the first discharge hole to prevent silicon dioxide leakage. (3) When the slip ring moves down and drives the auxiliary barrel to move down synchronously, the positions of the first discharge hole and the second discharge hole gradually correspond. At this time, the silica in the storage barrel is evenly discharged from the overlapping holes, realizing the intermittent feeding of NdFeB particles in the crushing chamber, effectively reducing the particle aggregation phenomenon caused by magnetic adsorption of NdFeB. (4) The connecting plate and the pressure block arranged in a staggered pattern on the lower surface of the slide are fixedly connected by the connecting rod. They will rise and fall synchronously with the slide. When the crushing component crushes the neodymium iron boron material, the pressure block can assist in dispersing and pre-compressing the falling material, further improving the crushing efficiency and material uniformity. (5) The upper surface of the crushing component is provided with permanent magnets. The permanent magnets are arranged in a tightly packed manner in the placement groove with alternating N and S poles to form a dynamically changing magnetic field area. When the NdFeB particles pass over the stainless steel cover plate during the crushing process, they will be affected by this alternating magnetic field, and the arrangement of the magnetic domains inside them will be disrupted, thereby effectively canceling the residual magnetism of the particles themselves. At the same time, the stainless steel cover plate not only provides good protection for the permanent magnets below, preventing dust generated during the crushing process from contaminating or damaging the permanent magnets, but its smooth surface can also reduce the adhesion of materials, ensuring that the NdFeB particles can pass smoothly through the demagnetization area and ensuring the stability and continuity of the demagnetization effect. Attached Figure Description

[0018] Figure 1 This is a three-dimensional structural diagram of the present invention; Figure 2 This is a three-dimensional cross-sectional view of the present invention; Figure 3 For the present invention Figure 2 Enlarged structural diagram at point A in the middle; Figure 4 This is a three-dimensional structural diagram of the crushing component of the present invention; Figure 5 This is a three-dimensional cross-sectional view of the crushing component of the present invention; Figure 6 For the present invention Figure 5 Enlarged structural diagram at point B; Figure 7 This is a schematic diagram of the three-dimensional structure of the carriage of the present invention; Figure 8 This is a three-dimensional sectional view of the carriage structure of the present invention; Figure 9 For the present invention Figure 8 Enlarged structural diagram at point C; Figure 10 This is a three-dimensional structural diagram of the storage tank of the present invention.

[0019] In the diagram: 1. Furnace shell; 2. Drive motor; 3. Crushing assembly; 4. Drive shaft; 5. Fixing rod; 6. Connecting column; 7. Slide groove; 8. Sliding block; 9. Slip ring; 10. Slide frame; 11. Feed pipe; 12. Storage hopper; 13. Auxiliary hopper; 14. First discharge hole; 15. Second discharge hole; 16. Stainless steel cover plate; 17. Permanent magnet; 18. Connecting rod; 19. Connecting plate; 20. Pressing block; 21. Placement slot. Detailed Implementation

[0020] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0021] Example 1: As Figure 1 - Figure 3 , Figure 7 - Figure 9The present invention provides the following technical solution: a vacuum crushing furnace with sealed feed and discharge for neodymium iron boron (NdFeB) materials. The furnace shell 1 is connected to an external vacuum system via a flange interface, comprising a vacuum pump, vacuum valves, and a vacuum gauge. A drive motor 2 is fixedly installed at the top center of the furnace shell 1. The output shaft of the drive motor 2 is connected to one end of a drive shaft 4 via a coupling. The other end of the drive shaft 4 extends into the furnace shell 1 and is connected to the crushing assembly 3. A connecting column 6 is fixedly connected to the upper outer side of the drive shaft 4. An intermittent feeding mechanism is provided on the outer side and inside the furnace shell 1. The intermittent feeding mechanism moves its auxiliary tank 13 by rotating the connecting column 6, thereby intermittently feeding non-magnetic powdered silica and reducing particle aggregation caused by magnetic adsorption of NdFeB. The intermittent feeding mechanism includes a feed pipe 11, which is installed above the furnace shell 1. The lower end of the feed pipe 11 is connected to a storage tank 12, which stores silica. The auxiliary tank 13 is sleeved on the outside of the storage tank 12. A sliding groove 7 is provided on the outer side of the connecting column 6, and a slider 8 is slidably connected inside the sliding groove 7. A sliding ring 9 is slidably connected to the outer side of the connecting column 6, and the sliding ring 9 is fixedly connected to the slider 8. The sliding groove 7 is an inclined annular structure. After the connecting column 6 rotates, the slider 8 and the sliding groove 7 cooperate to drive the sliding ring 9 to move up and down. A slide frame 10 is fixedly connected to the outer side of the sliding ring 9, and the outer end of the slide frame 10 is fixedly connected to the lower surface of the auxiliary barrel 13. Four sets of auxiliary barrels 13 are symmetrically distributed about the center point of the furnace shell 1. The inner surface of the furnace shell 1... A fixed rod 5 is fixedly connected to the part, and a slide 10 is slidably connected to the outside of the fixed rod 5. A second discharge hole 15 is opened on the outside of the auxiliary barrel 13, and a first discharge hole 14 is opened on the outside of the storage barrel 12. The diameter of the first discharge hole 14 is smaller than the maximum value of the diameter of the second discharge hole 15. In the initial state, the positions of the first discharge hole 14 and the second discharge hole 15 are offset from each other. The auxiliary barrel 13 blocks the first discharge hole 14. After the slip ring 9 moves down, the positions of the first discharge hole 14 and the second discharge hole 15 correspond, and silicon dioxide is discharged outward from the overlapping holes.

[0022] In actual operation, when the drive motor 2 starts and drives the drive shaft 4 to rotate, the connecting column 6 rotates synchronously. Since the slide groove 7 is an inclined annular structure, when the slider 8 slides in the slide groove 7, it will force the slip ring 9 to move up and down along the axis of the drive shaft 4. The up and down movement of the slip ring 9 is transmitted to the auxiliary barrel 13 through the slide frame 10, so that the auxiliary barrel 13 is axially displaced relative to the fixed storage barrel 12. When the slip ring 9 drives the auxiliary barrel 13 to move down to a specific position, the first discharge hole 14 on the storage barrel 12 and the second discharge hole 15 on the auxiliary barrel 13 are exactly completely overlapped. At this time, the silica powder in the storage barrel 12 falls into the crushing chamber inside the furnace shell 1 through the overlapping holes under its own gravity, realizing one feeding. As the connecting column 6 continues to rotate, the slider 8 continues to slide in the slide groove 7, and the slip ring 9 drives the auxiliary barrel 13 to move up. The first discharge hole 14 and the second discharge hole 15 are misaligned again, and the feeding stops. This cycle repeats continuously, achieving intermittent and quantitative addition of silica. This ensures that NdFeB particles are uniformly mixed with silica during the crushing process, effectively preventing particle agglomeration caused by magnetic attraction. This guarantees the dispersion and particle size uniformity of the NdFeB powder after crushing. Meanwhile, the design of four symmetrically distributed auxiliary barrels 13 and storage barrels 12 ensures that the silica addition points are evenly distributed in a circle above the crushing chamber, further improving the mixing effect. The sliding of the slide 10 on the fixed rod 5 provides stable guidance for the up-and-down movement of the slip ring 9 and auxiliary barrels 13, avoiding shaking and deviation during the movement, and ensuring the accuracy of the discharge hole alignment and the stability of the feeding process.

[0023] Example 2: Figure 7 , Figure 8 and Figure 10 The present invention provides the following technical solution: a vacuum crushing furnace for feeding and discharging neodymium iron boron, wherein a connecting rod 18 is fixedly connected to the lower surface of the slide 10, and a connecting plate 19 is fixedly connected to the lower end of the connecting rod 18, and a pressure block 20 is fixedly connected to the lower surface of the connecting plate 19, and the pressure blocks 20 are arranged in a staggered manner.

[0024] In actual operation, when the slide 10 moves up and down with the slip ring 9, the connecting plate 19 connected to the slide 10 via the connecting rod 18 will also move up and down synchronously. The pressure blocks 20 fixed on the lower surface of the connecting plate 19, due to their staggered arrangement, can effectively assist in dispersing and pre-compressing the NdFeB blocky materials or pre-crushed particles falling from above into the crushing area of ​​the crushing component 3 during the descent. Specifically, the higher pressure blocks 20 will first contact the accumulated material and apply a certain pressure to it to break up the larger lumps, while the lower pressure blocks 20 will further comb and compact the dispersed material, so that the material can be more evenly distributed on the working surface of the crushing component 3, avoiding the situation of too much or too little material accumulation in some areas. This pre-compression and dispersion effect can, on the one hand, reduce the impact load caused by uneven material distribution during the crushing process of the crushing component 3, protect the crushing components, extend their service life, and make the pre-treated material particles more uniform in size. After entering the crushing stage, the material can make more full contact with the crushing component 3, thereby improving crushing efficiency, shortening crushing time, and making the particle size distribution of the final crushed NdFeB particles more concentrated, thus improving product quality. The up-and-down movement of the briquette 20 can also agitate the airflow in the crushing chamber to a certain extent, which helps to carry the crushed fine particles away from the crushing area in time, and avoids the accumulation of fine particles at the bottom of the crushing chamber, which would affect the subsequent crushing effect.

[0025] Example 3: Figure 4 - Figure 6 The present invention provides the following technical solution: a sealed vacuum crushing furnace for feeding and discharging neodymium iron boron particles, wherein the upper surface of the crushing component 3 is provided with a demagnetizing mechanism for counteracting the residual magnetism of neodymium iron boron particles. The demagnetizing mechanism includes a placement groove 21, which is opened on the upper surface of the crushing component 3, and a permanent magnet 17 is fixedly connected inside the placement groove 21. The permanent magnet 17 is designed to be arranged in an alternating magnetic pattern. A stainless steel cover plate 16 is fixedly connected above the placement groove 21, and the stainless steel cover plate 16 shields the permanent magnet 17.

[0026] In actual operation, when the NdFeB material is crushed, it falls downwards and passes through the stainless steel cover plate 16 area on the upper surface of the crushing component 3. At this time, because the permanent magnets 17 in the placement groove 21 are closely arranged in an alternating N and S pole manner, a magnetic field region with dynamic changing characteristics is formed above the stainless steel cover plate 16. When the NdFeB particles pass through this region, the regular magnetic domain arrangement originally formed by the manufacturing process or external factors is disrupted by the strong interference of the alternating magnetic field, resulting in the effective cancellation of the residual magnetism of the particles themselves. This significantly reduces the possibility of NdFeB particles agglomerating due to magnetic attraction. The stainless steel cover plate 16 is made of high-strength stainless steel, which can effectively prevent metal dust and fine particles generated during the crushing process from entering the placement tank 21, avoiding contamination or damage to the magnetic properties of the permanent magnet 17 and ensuring the long-term stable operation of the demagnetizing mechanism. Moreover, its smooth surface, which has been precision polished, greatly reduces the friction and adhesion of the NdFeB particles when they pass through, allowing the particles to pass smoothly through the demagnetizing area. This ensures that each particle can fully receive the magnetic field, thereby ensuring the uniformity of the entire demagnetizing process and the stability and continuity of the demagnetizing effect. This provides reliable low-residual NdFeB particles for subsequent material handling and processing.

[0027] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A vacuum crushing furnace for feeding and discharging neodymium iron boron, comprising a furnace shell (1), wherein the furnace shell (1) is connected to a vacuum pump, vacuum valve and vacuum gauge of an external vacuum system via a flange interface, and a drive motor (2) is fixedly installed at the top center of the furnace shell (1), and the output shaft of the drive motor (2) is connected to one end of a drive shaft (4) via a coupling, characterized in that, The other end of the drive shaft (4) extends into the furnace shell (1) and is connected to the crushing component (3). A connecting column (6) is fixedly connected to the upper outer side of the drive shaft (4), and an intermittent feeding mechanism is provided between the outer side of the connecting column (6) and the interior of the furnace shell (1). The intermittent feeding mechanism drives the auxiliary bucket (13) contained therein to move in position by rotating the connecting column (6), so as to realize the intermittent feeding of non-magnetic powder silica, reducing the aggregation of NdFeB particles due to magnetic adsorption. A demagnetizing mechanism is provided on the upper surface of the crushing component (3) to counteract the residual magnetism of NdFeB particles.

2. The vacuum crushing furnace with sealed feed and discharge for NdFeB as described in claim 1, characterized in that: The intermittent feeding mechanism includes a feed pipe (11), which is installed above the furnace shell (1). The lower end of the feed pipe (11) is connected to a storage tank (12), which stores silicon dioxide. An auxiliary tank (13) is fitted on the outside of the storage tank (12).

3. The vacuum crushing furnace with sealed feed and discharge for NdFeB as described in claim 2, characterized in that: The outer side of the connecting column (6) is provided with a sliding groove (7), and a slider (8) is slidably connected inside the sliding groove (7). A sliding ring (9) is slidably connected to the outer side of the connecting column (6). At the same time, the sliding ring (9) and the slider (8) are fixedly connected. The sliding groove (7) is set in an inclined ring structure. After the connecting column (6) rotates, the slider (8) and the sliding groove (7) cooperate with each other to drive the sliding ring (9) to move up and down.

4. The vacuum crushing furnace with sealed feed and discharge for NdFeB as described in claim 3, characterized in that: The outer side of the slip ring (9) is fixedly connected to the slide frame (10), and the outer end of the slide frame (10) is fixedly connected to the lower surface of the auxiliary barrel (13). The auxiliary barrel (13) is symmetrically distributed with four sets about the center point of the furnace shell (1). The inside of the furnace shell (1) is fixedly connected to the fixing rod (5), and the slide frame (10) is slidably connected to the outside of the fixing rod (5).

5. The vacuum crushing furnace with sealed feed and discharge for NdFeB as described in claim 4, characterized in that: The auxiliary barrel (13) has a second discharge hole (15) on its outer side, and the storage barrel (12) has a first discharge hole (14) on its outer side, and the diameter of the first discharge hole (14) is smaller than the maximum value of the diameter of the second discharge hole (15).

6. The vacuum crushing furnace with sealed feed and discharge for NdFeB as described in claim 5, characterized in that: In the initial state, the positions of the first discharge hole (14) and the second discharge hole (15) are offset from each other. The auxiliary bucket (13) blocks the first discharge hole (14). After the slip ring (9) moves down, the positions of the first discharge hole (14) and the second discharge hole (15) correspond, and silicon dioxide is discharged outward from the overlapping holes.

7. The vacuum crushing furnace with sealed feed and discharge for NdFeB according to claim 6, characterized in that: The lower surface of the slide (10) is fixedly connected to a connecting rod (18), and the lower end of the connecting rod (18) is fixedly connected to a connecting plate (19). The lower surface of the connecting plate (19) is fixedly connected to a pressure block (20), and the pressure blocks (20) are arranged in an alternating pattern.

8. The vacuum crushing furnace with sealed feed and discharge for NdFeB according to claim 8, characterized in that: The demagnetizing mechanism includes a placement groove (21), which is opened on the upper surface of the crushing component (3), and a permanent magnet (17) is fixedly connected inside the placement groove (21).

9. The vacuum crushing furnace with sealed feed and discharge for neodymium iron boron as described in claim 8, characterized in that: The permanent magnets (17) are arranged in an alternating magnetic pattern. A stainless steel cover plate (16) is fixedly connected above the placement groove (21), and the stainless steel cover plate (16) shields the permanent magnets (17).

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