A sintering device for neodymium-iron-boron magnets

Abstract

The application belongs to the technical field of magnet sintering, and particularly relates to a sintering device for a neodymium-iron-boron magnet, which comprises a base, and comprises a furnace body arranged on the base, a cooling mechanism arranged on the furnace body, a heating mechanism arranged on the inner wall of the inner cylinder, and an air adjusting mechanism.

Description

Technical Field

[0001] This application belongs to the field of magnet sintering technology, and particularly relates to a sintering apparatus for neodymium iron boron magnets. Background Technology

[0002] Sintering is a crucial step in the production of NdFeB magnets, and the performance of the sintering equipment directly affects the final quality of the magnets. Currently, commonly used NdFeB magnet sintering equipment typically includes a sintering chamber, which requires maintaining a specific pressure and temperature environment during the sintering process to ensure the magnets achieve optimal performance.

[0003] After the sintering process is completed, before cooling the NdFeB magnets, it is necessary to restore the air pressure at the sintering chamber door to facilitate subsequent opening and removal of the magnets. Current equipment often restores air pressure by directly introducing ambient room temperature air into the sintering chamber. However, at this point, the NdFeB magnets inside the chamber have just completed sintering and are still in a hot state with a high temperature. The ambient room temperature air is relatively low, creating a significant temperature difference upon contact. This large temperature difference makes the hot NdFeB magnets highly susceptible to cracking due to uneven thermal expansion and contraction when in direct contact with the cold air, leading to product scrap or performance degradation. This severely impacts production efficiency and product quality, necessitating improvement. Utility Model Content

[0004] The purpose of this application is to provide a sintering apparatus for neodymium iron boron magnets that can solve the above-mentioned problems.

[0005] The purpose of this application is to provide a sintering apparatus for neodymium iron boron magnets, including a base, comprising:

[0006] The furnace body, set on the base, includes an inner cylinder and an outer cylinder, with a furnace door at its opening. A cavity is provided between the inner cylinder and the outer cylinder, and a clamp for placing materials is provided inside the inner cylinder.

[0007] A cooling mechanism, installed on the furnace body, is used to cool the furnace body.

[0008] The heating mechanism, located on the inner wall of the inner cylinder, includes an induction coil for heating the furnace body;

[0009] An air conditioning mechanism includes an air extractor, an air tank, and a connecting pipe disposed outside the outer cylinder. The input end of the air extractor is connected to the inside of the inner cylinder, and the two ends of the connecting pipe are connected to the cavity and the inside of the inner cylinder, respectively.

[0010] It also includes a control panel, which is mounted on the base and is electrically connected to the cooling mechanism, heating mechanism, and air conditioning mechanism.

[0011] The sintering apparatus for NdFeB magnets described above employs a double-layered furnace structure with an inner and outer cylinder. Combined with a furnace door at the opening, this effectively isolates the internal and external environments, reducing heat loss and external interference. The inner cylinder is equipped with clamps for placing materials, supporting the NdFeB magnets and driving their rotation. The cavity between the inner and outer cylinders provides space for subsequent gas heating and cooling medium flow, making temperature control easier and helping to maintain the stability of the internal environment of the inner cylinder.

[0012] During processing, after power is connected, the control panel controls the electric lifting rod to open and close the furnace door, simplifying the process of placing and removing magnets and reducing manual interference with the furnace environment. Inert gas is injected into the cavity; its insulating properties enhance the device's heat preservation, reduce heat transfer from the inner cylinder to the outside, maintain a stable high-temperature environment inside the inner cylinder, and reduce energy consumption. An air extractor creates a vacuum inside the inner cylinder, preventing impurities in the air from reacting with the high-temperature magnets and ensuring their purity. Induction coils use eddy current heating to ensure uniform heating of the magnets inside the inner cylinder, improving sintering quality and reducing performance differences caused by localized overheating.

[0013] After the NdFeB magnets are processed, when restoring the pressure in the inner cylinder, the inert gas from the storage tank is first introduced into the cavity by controlling the first and second control valves. The gas flowing through the outside of the inner cylinder is heated by the high-temperature inner cylinder, forming high-temperature gas before entering the inner cylinder, thus avoiding direct contact between the low-temperature gas and the hot magnet. This gradual restoration of gas pressure and matching of gas temperature with the inner cylinder environment solves the problem of magnet cracking caused by excessive temperature differences in existing devices, effectively improving the product qualification rate. Simultaneously, the gas flows along the spiral guide plate, extending the contact time with the outside of the inner cylinder, ensuring sufficient heating of the gas, and further ensuring a suitable temperature for the gas entering the inner cylinder.

[0014] When cooling the inner cylinder is required, restoring the gas pressure first can prevent damage to the furnace structure caused by excessive pressure difference between the inside and outside during the cooling process. Closing the two control valves prevents gas from interfering with the cooling process and ensures stable cooling. The water pump delivers coolant from the storage tank to the cavity. The coolant flows along the spiral guide plate, increasing the contact area and contact time with the inner cylinder, efficiently absorbing heat and achieving uniform cooling. This avoids stress concentration inside the magnet caused by rapid cooling, reducing the risk of magnet cracking. Opening the furnace door to remove material only after the inner cylinder has completely cooled prevents workers from contacting high-temperature components, improving operational safety.

[0015] Furthermore, the input end of the air extractor is connected to the interior of the inner cylinder via an air pipe, and a first control valve is installed on the air pipe, and a second control valve is installed on the connecting pipe. The first control valve, the second control valve and the control panel are electrically connected.

[0016] When restoring the air pressure inside the inner cylinder, the first and second control valves can be opened directly to allow the gas inside the storage tank to enter the cavity. Then, the gas inside the cavity flows along the guide of the spiral guide plate. The higher temperature of the outer side of the inner cylinder heats the gas flowing over its surface, so that the high-temperature gas flows into the inner cylinder through the second control valve after passing through the cavity, thereby gradually restoring the air pressure inside the inner cylinder. Since the temperature of the gas entering the inner cylinder is also high, the neodymium iron boron magnet will not crack due to the large temperature difference.

[0017] Furthermore: the cooling mechanism includes:

[0018] The water storage tank contains coolant and is connected to the cavity via water pipes.

[0019] The water pump is connected to the water storage tank and the cavity via water pipes.

[0020] Spiral guide vanes, installed on the inner wall of the cavity, are used to guide coolant and air;

[0021] The water pipes at both ends of the water storage tank are connected to both ends of the cavity.

[0022] In the cooling mechanism, a water tank stores coolant and is connected to the cavity via water pipes, forming a coolant circulation loop to ensure continuous cooling. A water pump provides power for the coolant flow, ensuring efficient circulation between the water tank and the cavity. Spiral guide vanes guide the coolant and air along specific paths, increasing the contact time and area between the fluid and the inner cylinder, improving heat exchange efficiency, and resulting in a more uniform temperature distribution, preventing localized overheating or undercooling. This makes the cooling and heating processes more efficient and stable, contributing to ensuring the quality of the magnet.

[0023] Furthermore, the water storage tank is also equipped with heat dissipation fins and a heat dissipation fan, and a heat conduction plate is provided between the heat dissipation fan and the water storage tank.

[0024] The heat dissipation fins installed on the water storage tank increase the heat dissipation area, enabling rapid dissipation of heat absorbed by the coolant within the tank to the outside. The cooling fan accelerates heat transfer within the tank via a heat-conducting plate, further improving heat dissipation efficiency and ensuring the coolant remains at a consistently low temperature, guaranteeing stable cooling performance. This prevents a decrease in cooling capacity due to increased coolant temperature, ensuring rapid and uniform cooling of the inner cylinder, shortening the production cycle, and improving production efficiency.

[0025] Furthermore, an electric telescopic rod is provided on the outer wall of the furnace body, and the telescopic end of the electric telescopic rod is connected to the furnace door.

[0026] An electric telescopic rod installed on the outer wall of the furnace body connects to the furnace door, enabling automatic opening and closing of the door via electric control. This makes operation convenient and labor-saving, reducing errors and labor intensity associated with manual operation. Simultaneously, the electric control ensures a tighter seal of the furnace door, guaranteeing the furnace's airtightness and preventing outside air from entering the inner cylinder or gas leakage from the inner cylinder. This maintains a stable internal environment, which is beneficial for improving sintering quality and operational safety.

[0027] Furthermore, an insulation layer is also provided on the outer wall of the furnace body.

[0028] The insulation layer on the outer wall of the furnace effectively reduces heat transfer from the inner cylinder to the outside, minimizing heat loss and maintaining a stable internal temperature, thus reducing energy consumption of the heating mechanism. Simultaneously, the insulation layer prevents excessively high external temperatures, protecting workers from accidental burns and enhancing the safety of the equipment. A stable internal temperature environment also helps ensure consistency in the magnet sintering process, improving product quality stability.

[0029] The beneficial effects of this application are:

[0030] 1. By setting up an air conditioning mechanism, the inert gas in the storage tank is heated through the cavity and then enters the inner cylinder, gradually restoring the air pressure in the inner cylinder, effectively solving the existing cracking problem and improving the product qualification rate.

[0031] 2. By coordinating the cooling and heating mechanisms, and installing spiral guide plates to enhance heat exchange efficiency, and installing insulation layers to reduce energy consumption, the system effectively ensures stable temperature regulation.

[0032] 3. Installing an electric telescopic rod makes opening and closing the furnace door more convenient and also ensures a tight seal. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of the structure of this utility model;

[0034] Figure 2 This is a schematic diagram of the furnace body of this utility model;

[0035] Figure 3 This is a schematic diagram of the internal structure of the furnace body of this utility model.

[0036] The attached figures are labeled as follows: 100, base; 200, furnace body; 210, inner cylinder; 220, outer cylinder; 230, furnace door; 240, cavity; 250, clamp; 260, insulation layer; 300, cooling mechanism; 310, water storage tank; 320, water pump; 330, spiral guide plate; 340, heat dissipation fins; 350, heat dissipation fan; 400, heating mechanism; 410, induction coil; 500, air conditioning mechanism; 510, air extractor; 520, air tank; 530, connecting pipe; 540, air pipe; 550, first control valve; 560, second control valve; 600, control panel; 700, electric telescopic rod. Detailed Implementation

[0037] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0038] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0039] The sintering apparatus for neodymium iron boron magnets provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0040] Example 1:

[0041] like Figures 1 to 3 As shown, this application embodiment provides a sintering apparatus for neodymium iron boron magnets, including a base 100, comprising:

[0042] The furnace body 200 is mounted on the base 100 and includes an inner cylinder 210 and an outer cylinder 220. The furnace body has an opening with a furnace door 230. A cavity 240 is provided between the inner cylinder 210 and the outer cylinder 220. A clamp 250 for placing materials is provided inside the inner cylinder 210.

[0043] A cooling mechanism 300 is installed on the furnace body 200 and is used to cool the furnace body 200.

[0044] Heating mechanism 400 is disposed on the inner wall of inner cylinder 210, including induction coil 410, for heating furnace body 200;

[0045] The air conditioning mechanism 500 includes an air extractor 510, an air tank 520, and a connecting pipe 530 disposed outside the outer cylinder 220. The input end of the air extractor 510 is connected to the inside of the inner cylinder 210, and the two ends of the connecting pipe 530 are connected to the cavity 240 and the inside of the inner cylinder 210, respectively.

[0046] It also includes a control panel 600, which is mounted on the base 100 and is electrically connected to the cooling mechanism 300, the heating mechanism 400, and the air conditioning mechanism 500.

[0047] In some embodiments of this application, such as Figure 1 As shown, the sintering apparatus for NdFeB magnets described above employs a double-layer structure of an inner cylinder 210 and an outer cylinder 220 in the furnace body 200. Combined with the furnace door 230 at the opening, this effectively isolates the internal and external environments, reducing heat loss and external interference. A clamp 250 for placing materials is installed inside the inner cylinder 210, which can support the NdFeB magnets and drive their rotation. The cavity 240 between the inner cylinder 210 and the outer cylinder 220 provides space for subsequent gas heating and cooling medium flow, making temperature regulation easier to control and helping to maintain the stability of the internal environment of the inner cylinder 210.

[0048] During processing, after power is connected, the control panel 600 controls the electric lifting rod to operate the furnace door 230, simplifying the process of placing and removing magnets and reducing the interference of manual operation on the furnace environment. Inert gas is injected into the cavity 240, utilizing its insulating properties to enhance the device's heat preservation effect and reduce heat transfer from the inner cylinder 210 to the outside, thus maintaining a stable high-temperature environment inside the inner cylinder 210 and reducing energy consumption. The air extractor 510 evacuates the inner cylinder 210 into a vacuum, preventing impurities in the air from reacting with the high-temperature magnets and ensuring the purity of the magnets. The induction coil 410, through eddy current heating, ensures uniform heating of the magnets inside the inner cylinder 210, improving sintering quality and reducing performance differences caused by localized overheating.

[0049] After the NdFeB magnets are processed, when restoring the pressure in the inner cylinder 210, the inert gas from the gas storage tank 520 is first introduced into the cavity 240 by controlling the first control valve 550 and the second control valve 560. The gas flowing through the outside of the inner cylinder 210 is heated by the high-temperature inner cylinder 210, forming high-temperature gas before entering the inner cylinder 210, thus avoiding direct contact between the low-temperature gas and the hot magnet. This method of gradually restoring the gas pressure and matching the gas temperature with the environment of the inner cylinder 210 solves the problem of magnet cracking caused by excessive temperature difference in existing devices, effectively improving the product qualification rate. At the same time, the gas flows along the spiral guide plate 330, prolonging the contact time with the outside of the inner cylinder 210, ensuring that the gas is fully heated, and further ensuring that the temperature of the gas entering the inner cylinder 210 is suitable.

[0050] When cooling the inner cylinder 210 is required, restoring the gas pressure first can prevent damage to the furnace body 200 structure due to excessive pressure difference between the inside and outside during the cooling process. Closing the two control valves prevents gas interference with the cooling process and ensures stable cooling. The water pump 320 delivers coolant from the water storage tank 310 to the cavity 240. The coolant flows along the spiral guide plate 330, increasing the contact area and contact time with the inner cylinder 210, efficiently absorbing heat from the inner cylinder 210 and achieving uniform cooling. This avoids stress concentration inside the magnet caused by rapid cooling, reducing the risk of magnet cracking. Opening the furnace door 230 to remove material only after the inner cylinder 210 has completely cooled prevents workers from contacting high-temperature components, improving operational safety.

[0051] Furthermore, an insulation layer 260 is also provided on the outer wall of the furnace body 200.

[0052] The insulation layer 260 on the outer wall of the furnace body 200 effectively reduces heat transfer from the inner cylinder 210 to the outside, lowers heat loss, maintains a stable internal temperature within the inner cylinder 210, and reduces energy consumption of the heating mechanism 400. Simultaneously, the insulation layer 260 prevents excessively high external temperatures of the furnace body 200, preventing accidental burns to personnel and improving the safety of the equipment. A stable internal temperature environment also helps ensure the consistency of the magnet sintering process, improving product quality stability.

[0053] Example 2:

[0054] This application provides a sintering apparatus for neodymium iron boron magnets. In addition to the above-mentioned technical features, the sintering apparatus for neodymium iron boron magnets in this application also includes the following technical features.

[0055] like Figure 1 As shown, the input end of the air extractor 510 is connected to the interior of the inner cylinder 210 through the air pipe 540, and a first control valve 550 is provided on the air pipe 540, and a second control valve 560 is provided on the connecting pipe 530. The first control valve 550 and the second control valve 560 are electrically connected to the control panel 600.

[0056] In this embodiment, when restoring the air pressure inside the inner cylinder 210, the first control valve 550 and the second control valve 560 can be opened directly to allow the gas inside the gas storage tank 520 to enter the cavity 240. Then, the gas inside the cavity 240 flows along the guide of the spiral guide plate 330. The outer side of the inner cylinder 210, which has a higher temperature, heats the gas flowing over its surface, so that the high-temperature gas flows into the inner cylinder 210 through the second control valve 560 after passing through the cavity 240, thereby gradually restoring the air pressure inside the inner cylinder 210. Since the gas temperature entering the inner cylinder 210 is also high, the neodymium iron boron magnet will not crack due to a large temperature difference.

[0057] Example 3:

[0058] This application provides a sintering apparatus for neodymium iron boron magnets. In addition to the above-mentioned technical features, the sintering apparatus for neodymium iron boron magnets in this application also includes the following technical features.

[0059] like Figure 1 As shown, the cooling mechanism 300 includes:

[0060] The water storage tank 310 contains coolant and is connected to the cavity 240 via a water pipe.

[0061] The water pump 320 is connected to the water storage tank 310 and the cavity 240 via water pipes.

[0062] Spiral guide vane 330 is disposed on the inner wall of cavity 240 to guide coolant and air;

[0063] The water pipes at both ends of the water storage tank 310 are connected to both ends of the cavity 240.

[0064] In this embodiment, the cooling mechanism 300 includes a water storage tank 310 storing coolant and connected to the cavity 240 via a water pipe, forming a coolant circulation loop to ensure continuous cooling. A water pump 320 provides power for the coolant flow, ensuring efficient circulation between the water storage tank 310 and the cavity 240. A spiral guide plate 330 guides the coolant and air along a specific path, increasing the contact time and area between the fluid and the inner cylinder 210, improving heat exchange efficiency, and resulting in a more uniform temperature distribution, preventing localized overheating or overcooling. This makes the cooling and heating processes more efficient and stable, which is beneficial for ensuring the quality of the magnet.

[0065] Furthermore, the water storage tank 310 is also equipped with heat dissipation fins 340 and a heat dissipation fan 350, and a heat conduction plate is provided between the heat dissipation fan 350 and the water storage tank 310.

[0066] The heat dissipation fins 340 installed on the water storage tank 310 increase the heat dissipation area, enabling rapid dissipation of heat absorbed by the coolant inside the tank to the outside. The cooling fan 350 accelerates heat transfer within the tank 310 via a heat-conducting plate, further improving heat dissipation efficiency and ensuring the coolant remains at a consistently low temperature, guaranteeing stable cooling performance. This prevents a decrease in cooling capacity due to increased coolant temperature, ensuring rapid and uniform cooling of the inner cylinder 210, shortening the production cycle, and improving production efficiency.

[0067] Example 4:

[0068] This application provides a sintering apparatus for neodymium iron boron magnets. In addition to the above-mentioned technical features, the sintering apparatus for neodymium iron boron magnets in this application also includes the following technical features.

[0069] like Figure 1 As shown, an electric telescopic rod 700 is installed on the outer wall of the furnace body 200, and the telescopic end of the electric telescopic rod 700 is connected to the furnace door 230.

[0070] In this embodiment, an electric telescopic rod 700 installed on the outer wall of the furnace body 200 is connected to the furnace door 230. The furnace door 230 is automatically opened and closed via electric control, making operation convenient and labor-saving, reducing errors and labor intensity caused by manual operation. Simultaneously, electric control ensures a tighter closure of the furnace door 230, guaranteeing the airtightness of the furnace body 200, preventing outside air from entering the inner cylinder 210 or gas leakage from the inner cylinder 210, maintaining a stable internal environment within the inner cylinder 210, and thus improving sintering quality and operational safety.

[0071] It should be noted that, in this document, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0072] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

Claims

1. A sintering apparatus for neodymium iron boron magnets, comprising a base (100), characterized in that: include: The furnace body (200) is set on the base (100) and includes an inner cylinder (210) and an outer cylinder (220). The furnace body has a furnace door (230) at its opening. A cavity (240) is provided between the inner cylinder (210) and the outer cylinder (220). A clamp (250) for placing materials is provided inside the inner cylinder (210). A cooling mechanism (300) is installed on the furnace body (200) to cool the furnace body (200); A heating mechanism (400) is provided on the inner wall of the inner cylinder (210) and includes an induction coil (410) for heating the furnace body (200); The air conditioning mechanism (500) includes an air extractor (510), an air tank (520), and a connecting pipe (530) disposed outside the outer cylinder (220). The input end of the air extractor (510) is connected to the inside of the inner cylinder (210), and the two ends of the connecting pipe (530) are connected to the cavity (240) and the inside of the inner cylinder (210), respectively. It also includes a control panel (600) mounted on the base (100), which is electrically connected to the cooling mechanism (300), the heating mechanism (400), and the air conditioning mechanism (500).

2. The sintering apparatus for a neodymium iron boron magnet according to claim 1, characterized in that: The input end of the air extractor (510) is connected to the interior of the inner cylinder (210) through an air pipe (540), and a first control valve (550) is provided on the air pipe (540), and a second control valve (560) is provided on the connecting pipe (530). The first control valve (550), the second control valve (560) are electrically connected to the control panel (600).

3. The sintering apparatus for a neodymium iron boron magnet according to claim 2, characterized in that: The cooling mechanism (300) includes: A water storage tank (310) contains coolant and is connected to a cavity (240) via a water pipe; A water pump (320) is connected to a water storage tank (310) and a cavity (240) via water pipes. A spiral guide plate (330) is disposed on the inner wall of the cavity (240) to guide the coolant and air; The water pipes at both ends of the water storage tank (310) are connected to both ends of the cavity (240).

4. The sintering apparatus for a neodymium iron boron magnet according to claim 3, characterized in that: The water storage tank (310) is also equipped with heat dissipation fins (340) and a heat dissipation fan (350), and a heat conduction plate is provided between the heat dissipation fan (350) and the water storage tank (310).

5. The sintering apparatus for a neodymium iron boron magnet according to claim 4, characterized in that: An electric telescopic rod (700) is provided on the outer wall of the furnace body (200), and the telescopic end of the electric telescopic rod (700) is connected to the furnace door (230).

6. The sintering apparatus for a neodymium iron boron magnet according to claim 1, characterized in that: The outer wall of the furnace body (200) is also provided with a heat insulation layer (260).

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