Vacuum sintering furnace
By designing a highly automated vacuum sintering furnace, the oxidation problems and manual operation uncertainty in the production process of rare earth permanent magnet materials are solved, and high-quality and stable rare earth permanent magnet materials are achieved.
Patent Information
- Application Number
- CN202411895661.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-23
- Publication Date
- 2025-02-18
AI Technical Summary
The prior art has oxidation problems, poor line adaptability and manual operation uncertainty in the production process of rare earth permanent magnet materials, resulting in product consistency and quality stability being affected.
A highly automated and intelligent vacuum sintering furnace is designed, including furnace shells, isolation valves, material moving devices, heating chambers and vacuum systems. Through automated material transfer and vacuum sintering processes, the materials are ensured to the atmosphere throughout the production process. isolation.
It realizes high-quality production of rare earth permanent magnet materials, reduces oxygen content, improves production efficiency, reduces uncertainty caused by manual operation, improves product quality stability, and reduces production costs.
Smart Images
Figure CN119468711A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the field of advanced equipment, and in particular relates to a vacuum sintering furnace which can be used for vacuum sintering of rare earth permanent magnetic materials. Background Art
[0002] After 2020, with the development of smart phones, new energy vehicles, robots, artificial intelligence and aerospace, the demand for rare earth permanent magnets is increasing, and rare earths have become a scarce material in the world. Rare earth is a general term for 17 elements, mixed together in the form of oxides. NdFeB rare earth permanent magnets mainly use light rare earths praseodymium and neodymium and heavy rare earths dysprosium and terbium. Praseodymium and neodymium account for about 20% of the total rare earths, and heavy rare earths dysprosium and terbium account for less than 5% of the total rare earths; light rare earth elements such as lanthanum and cerium, which account for 70% of the total rare earths, are not used, and the supply of heavy rare earth elements dysprosium and terbium is tight. The application of rare earth resources is extremely unbalanced, resulting in a huge waste of rare earth resources.
[0003] The industrial preparation of rare earth permanent magnet materials generally adopts powder metallurgy technology. First, the raw materials are made into rare earth permanent magnet alloys, and then the rare earth permanent magnet alloys are made into 3-5μm powders, which are oriented and formed under a magnetic field. After being taken out, they are sealed and packaged, isostatically pressed, and vacuum sintered after removing the packaging to obtain rare earth permanent magnet sintered blanks, that is, rare earth permanent magnet materials. Rare earth permanent magnet powders are extremely easy to oxidize and can burn themselves in the atmosphere. They must be isolated from the atmosphere during the production process of rare earth permanent magnets. The oxidation problem in the production process has always restricted the development of the industry and seriously affected product consistency. At present, the magnetic field presses and vacuum sintering furnaces used in the industry are mostly produced by different manufacturers, and there is a phenomenon of poor production line adaptability. In the process of molding alloy powder into compacts and sintering blanks, most of the processes require manual participation to complete the preparation of materials, placing and packing, stacking and loading the boxes into the furnace, as well as the transportation of materials between the various processes and the removal of sintered blanks. This will bring several problems, including that the materials are easily exposed to the external environment during manual operation, resulting in different degrees of oxidation, which will affect the further improvement of the performance of rare earth permanent magnet materials; in addition, manual operation will not only reduce production efficiency, consume human resources, and increase production costs, but also affect the stability of product quality due to the uncertainty of manual operation, bringing a certain defective rate to product production. In addition, after the vacuum sintering process is completed, the stacked boxes need to be layered and laid flat so that the sintered blanks can be taken out of the boxes. The temperature of the sintered blanks when they are out of the furnace is generally 50-200℃, which brings many inconveniences to the operation of the boxes and the blanks in the boxes.
[0004] Therefore, it is urgent to develop a vacuum sintering furnace equipment with better production line adaptability and higher degree of automation to change the current situation in the industry. Summary of the invention
[0005] In order to solve the above problems, the present invention proposes a vacuum sintering furnace for manufacturing high-quality rare earth permanent magnet materials. The vacuum sintering furnace can be applied to a highly automated and intelligent rare earth permanent magnet intelligent production line.
[0006] The vacuum sintering furnace includes a furnace shell, a first isolation valve, a material moving device, a heating chamber and a vacuum system; the vacuum system is connected to the furnace shell and is used to evacuate the furnace shell; the first isolation valve is connected to the front flange of the furnace shell; the heating chamber is arranged in the furnace shell and includes a movable bottom plate assembly; the bottom plate assembly includes a sintering material box support, a heat insulation screen and a bottom plate shell, and rollers are arranged on the bottom plate shell, and the bottom plate assembly can be moved along the track on the inner wall of the furnace shell through the rollers; the material moving device includes a moving rod, a sealing assembly and a transmission device, the transmission device is arranged outside the furnace shell, the sealing assembly is connected to the furnace shell, and the transmission device drives the moving rod to pass through the sealing assembly and enter the furnace shell; the moving rod is connected to the bottom plate assembly to drive the bottom plate assembly to move. A heater is arranged in the heating chamber.
[0007] The bottom plate assembly also includes a heater, which is arranged on the heat insulation screen; the material moving device has two moving rods, and electrodes for energizing the heater are arranged inside the moving rods and cooling water is passed through them.
[0008] The vacuum sintering furnace also includes an air-cooled heat exchange system and an air charging system; the air-cooled heat exchange system is arranged at the rear of the furnace shell, and the air inlet pipe of the air-cooled heat exchange system is connected to the furnace shell; the air-cooled heat exchange system includes a cooling fan and a heat exchanger; the air charging system includes an air charging valve; after the heating is completed, the air charging valve is opened to charge the vacuum sintering furnace with protective gas, and the cooling fan is started when the pressure in the furnace reaches the set value.
[0009] In a preferred embodiment, the vacuum sintering furnace is a horizontal structure, the furnace shell is provided with a water cooling jacket, and the vacuum sintering furnace further comprises a cooling system, and the cooling system provides cooling for the furnace shell.
[0010] The heating chamber also includes two side panel assemblies, which are respectively located on the left and right sides of the heating chamber; the air outlet pipe of the air-cooled heat exchange system is divided into two pipelines before entering the furnace shell, each pipeline is provided with a valve, and the pipeline passes through the furnace shell and is respectively connected to the two side panel assemblies of the heating chamber; the side panel assembly includes a side panel shell, a heat insulation screen and a nozzle; the nozzle is fixed on the side panel shell, and extends through the heat insulation screen of the side panel assembly to the inside of the heating chamber; the two valves are switched simultaneously or alternately. A pipeline is provided on the outside of the side panel assembly, and the pipeline is connected with the nozzle and the pipeline, and the gas flowing out of the air outlet pipe of the air-cooled heat exchange system is sprayed into the inside of the heating chamber through the nozzle.
[0011] The heating chamber also includes a front cover assembly and an upper plate assembly.
[0012] After the first isolation valve is opened, the bottom plate assembly can be moved to the outside of the vacuum sintering furnace; a movable conveying material box is arranged outside the vacuum sintering furnace; the vacuum sintering furnace can be docked with the conveying material box arranged outside the vacuum sintering furnace through the first isolation valve; after the vacuum sintering furnace is docked with the conveying material box, the bottom plate assembly moves to the conveying material box to carry the sintering material box containing the pressed blanks in the conveying material box, and then returns to the vacuum sintering furnace with the sintering material box, and then, the conveying material box and the vacuum sintering furnace are separated, and the vacuum sintering furnace performs the vacuum sintering process.
[0013] After the vacuum sintering process is completed, the vacuum sintering furnace and the conveying material box are connected, and the sintering material box containing the sintered blanks is transferred from the vacuum sintering furnace to the conveying material box through the bottom plate assembly; before and after the vacuum sintering furnace and the conveying material box are connected, the atmosphere in the conveying material box and the vacuum sintering furnace is kept isolated from the atmosphere.
[0014] In one embodiment of the present invention, the vacuum system of the vacuum sintering furnace includes a mechanical vacuum pump that directly exhausts to the atmosphere and a Roots vacuum pump that further increases the vacuum degree in the furnace.
[0015] In a more preferred embodiment of the present invention, the vacuum sintering furnace also includes a material box cover opening device and a cover opening assembly; a sintering material box is placed on the sintering material box bracket; the cover opening assembly is located on the inner side of the heater and distributed on both sides of the sintering material box; the material box cover opening device is located on the upper part of the vacuum furnace shell, and a guide shaft passes through the vacuum furnace shell and the heat preservation screen of the heating chamber to connect with the cover opening assembly; the material box cover opening device can drive the guide shaft to drive the cover opening assembly to move up and down. When the vacuum sintering furnace is working, the cover opening assembly drives the box covers of the sintering material boxes loaded in the vacuum sintering furnace to open or close at the same time, and there are more than 3 layers of sintering material boxes loaded in the furnace, and each layer of sintering material boxes has more than 1 box cover.
[0016] In one embodiment, the vacuum sintering furnace also includes a conveying material box; the conveying material box includes a conveying material box shell, a material box clamping and lifting device, a longitudinal moving device, a transverse moving device and a second isolation valve; the second isolation valve is connected to the conveying material box shell; the conveying material shell is installed on the transverse moving device, and the longitudinal moving device drives the conveying material box shell together with the second isolation valve to move on the transverse moving device; the conveying material box carrying the multi-layer sintering material box containing the pressed blank can be moved to the opposite side of the vacuum sintering furnace and docked with the vacuum sintering furnace, and the first isolation valve and the second isolation valve are opened to transfer the multi-layer sintering material box in the conveying material box to the vacuum sintering furnace, and then, the first isolation valve and the second isolation valve are closed to separate the conveying material box from the vacuum sintering furnace; after the vacuum sintering process of the vacuum sintering furnace is completed, the conveying material box and the vacuum sintering furnace are docked again, the first isolation valve and the second isolation valve are opened to transfer the sintering material box containing the sintered blank to the conveying material box, and then, the first isolation valve and the second isolation valve are closed to separate the conveying material box from the vacuum sintering furnace.
[0017] The present invention also relates to a rare earth permanent magnet intelligent production line, which includes an automatic magnetic field press, a magnetic block conveyor, a box, a conveying box and the above-mentioned vacuum sintering furnace. There are more than two automatic magnetic field presses, which are arranged side by side, and one end of each automatic magnetic field press is respectively connected to the side of the magnetic block conveyor, and one end of the magnetic block conveyor is connected to the box; the automatic magnetic field press, the magnetic block conveyor and the box constitute a closed space, which is filled with protective gas; the automatic magnetic field press presses the rare earth alloy powder into a compact and then conveys it to a conveyor belt arranged in the magnetic block conveyor, and conveys the compact to the box through the conveyor belt; the magnetic block conveyor serves as a common conveying channel of the automatic magnetic field press, and conveys the compact pressed by each automatic magnetic field press to the box. A robot is arranged in the box packing box, which grabs the compact and puts it into the sintering box placed in the box packing box; there are more than two vacuum sintering furnaces; the box packing box and the vacuum sintering furnace are arranged side by side, and the conveying box can be moved to the opposite side of the box packing box and the vacuum sintering furnace respectively through horizontal movement, and then the conveying box is connected with the box packing box and the vacuum sintering furnace respectively through vertical movement; a second isolation valve is arranged at one end of the conveying box; a third isolation valve is arranged at one end of the box packing box; after the conveying box is connected with the box packing box, the second isolation valve and the third isolation valve are opened, and the space in the conveying box is connected with the space in the box packing box, and then the sintering box can be moved between the box packing box and the conveying box; before the box packing box and the conveying box are separated, the second isolation valve and the third isolation valve are closed first to ensure that the box packing box and the conveying box are sealed and airtight; After the conveying box of the material box is separated from the box loading box, it is moved to the opposite side of the vacuum sintering furnace and docked with the vacuum sintering furnace. After docking, the first isolation valve and the second isolation valve are opened to convey the sintering box containing the pressed blanks in the conveying box to the vacuum sintering furnace, and then the conveying box is separated from the vacuum sintering furnace; before the conveying box and the vacuum sintering furnace are separated, the first isolation valve and the second isolation valve are closed first to isolate the atmosphere in the conveying box and the vacuum sintering furnace from the atmosphere; after the vacuum sintering process of the vacuum sintering furnace is completed, the sintering box containing the sintered blanks is conveyed to the conveying box through the docking of the conveying box and the vacuum sintering furnace, and then the conveying box and the vacuum sintering furnace are separated; in the rare earth permanent magnet intelligent production line, magnetic field forming and vacuum sintering are automatically realized under nitrogen protection or vacuum conditions to produce rare earth permanent magnet sintered blanks.
[0018] The rare earth permanent magnet intelligent production line also includes a discharge mechanism, which is also arranged side by side with the box loading box and the vacuum sintering furnace; the conveying box can be moved horizontally to the opposite side of the discharge mechanism, and then docked with the discharge mechanism through longitudinal movement. After docking, the second isolation valve is opened, and the sintering box in the conveying box can be conveyed to the discharge mechanism, or the sintering box on the discharge mechanism can be conveyed to the conveying box.
[0019] The automatic magnetic field press comprises a powder storage device, an automatic powder loading device, a powder loading box, a press frame, an upper pressure head assembly, a mold device, a lower pressure head assembly and an electromagnetic orientation magnetic pole; the powder storage device is located above the powder loading box; the automatic powder loading device is arranged inside the powder loading box; the NdFeB alloy powder loaded in the powder storage device is quantitatively loaded into the mold cavity of the mold device through the automatic powder loading device; the upper pressure head assembly, the mold device, the lower pressure head assembly and the electromagnetic orientation magnetic pole are arranged in the press frame; the upper pressure head assembly and the lower pressure head assembly are arranged above and below the mold device respectively; there are two electromagnetic orientation magnetic poles, which are respectively located on both sides of the mold device; the mold device, the upper pressure head assembly, the lower pressure head assembly and the electromagnetic orientation magnetic pole realize bidirectional pressing of the powder in the mold cavity under magnetic field orientation, and press the powder into a compact; one side of the press frame is connected to the powder loading box, and the other side is connected to the magnetic block conveying device; the compact is ejected from the mold cavity and conveyed to the conveyor belt. The automatic magnetic field press is also provided with an electromagnetic orientation coil, which is sleeved on the outside of the electromagnetic orientation magnetic pole.
[0020] The magnetic block conveying device includes a conveying device box; one end of the conveying device box is connected to the box packing box, and the side is connected to the automatic magnetic field press; a sensor for detecting whether there is a pressed blank at that position is arranged near the interface connecting the automatic magnetic field press and the conveying device box, and the sensor is used to control that the pressed blanks pressed by different automatic magnetic field presses do not collide with each other.
[0021] In a preferred embodiment, the rare earth permanent magnet intelligent production line includes more than 4 automatic magnetic field presses.
[0022] The box loading box includes a box loading box body and a sintering material box conveying device; one end of the box loading box body is connected to the third isolation valve, and the side is connected to the magnetic block conveying device; the conveyor belt in the magnetic block conveying device extends into the box loading box body; the manipulator and the sintering material box conveying device are arranged in the box loading box body; the manipulator grabs the compact conveyed into the box loading box body and puts it into the sintering material box on the sintering material box conveying device; after the box loading box and the conveying material box are docked, the sintering material box conveying device can reciprocate in the box loading box and the conveying material box. The sintering material box conveying device can move horizontally or up and down.
[0023] In one embodiment of the present invention, there are wheels at the bottom of the press frame, which can move along the axis formed by the powder box, the press frame and the magnetic block conveying device, and the powder box can also move. When the automatic magnetic field press needs to be maintained, the press frame can be disconnected from the magnetic block conveying device, and then the press frame and the powder box move away from the magnetic block conveying device; when the automatic magnetic field press needs to be restored to working state after maintenance, the press frame and the powder box move toward the magnetic block conveying device, and restore the connection between the press frame and the magnetic block conveying device. On the magnetic block conveying device, a fourth isolation valve is provided at the interface connected to the automatic magnetic field press; when the automatic magnetic field press is disconnected from the magnetic block conveying device, it is necessary to close the fourth isolation valve first to make the magnetic block conveying device airtight, and continue to keep the protective gas atmosphere unchanged in the enclosed space formed by the magnetic block conveying device, the box and the automatic magnetic field press in working state. The maintenance of the automatic magnetic field press includes replacing molds, overhauling and other work.
[0024] The magnetic block conveyor serves as a common conveying channel for the automatic magnetic field presses, and conveys the compacts pressed by each automatic magnetic field press into the box. Even if an automatic magnetic field press is undergoing maintenance or is restored to work after maintenance, the airtightness of the magnetic block conveyor is not affected, and it can still be used as a common conveying channel to provide automatic conveying of compacts for other automatic magnetic field presses, ensuring the normal operation of the rare earth permanent magnet intelligent production line.
[0025] The discharging mechanism includes a material taking device, a fixed transfer assembly, a moving roller assembly and a fixed roller assembly; the material taking device is arranged on the fixed transfer assembly, and a conveying roller is also arranged on the fixed transfer assembly; after the conveying material box is docked with the discharging mechanism, the material taking device can reciprocate between the conveying material box and the discharging mechanism; the moving roller assembly is docked with the fixed transfer assembly, or with one or more fixed roller assemblies; when working, the material taking device enters the conveying material box, takes out the sintering material box and puts it on the conveying roller of the fixed transfer assembly, and the conveying roller of the fixed transfer assembly then conveys the sintering material box to the moving roller assembly; the moving moving roller assembly first docks with a group of fixed roller assemblies, and conveys the sintering material box to this group of fixed roller assemblies, and then the moving moving roller assembly docks with another group of fixed roller assemblies carrying empty sintering material boxes, and conveys the empty sintering material boxes to the moving roller assembly, and then the empty sintering material boxes are conveyed to the conveying material box through the moving roller assembly and the material taking device.
[0026] The conveying material box includes a conveying material box shell, a material box clamping and lifting device, a longitudinal moving device and a transverse moving device; the second isolation valve is connected to the conveying material box shell; the conveying material box shell is installed on the guide rail of the transverse moving device, and the conveying material box shell together with the second isolation valve moves longitudinally on the guide rail of the transverse moving device to achieve the docking of the conveying material box with the box loading box, or with the vacuum sintering furnace.
[0027] After the packing box and the conveying box are docked, the process of automatically loading the compacts into the sintering boxes and automatically stacking the sintering boxes is completed through the reciprocating movement of the sintering box conveying device of the packing box and the lifting and lowering of the box clamping and lifting device in the conveying box, in coordination with the action of the robot.
[0028] In a more preferred embodiment of the present invention, the conveying material box also includes a material bed; there are multiple sintering material boxes in the conveying material box shell, which are arranged in n layers up and down and placed on the material bed, and n ≥ 3. The process of loading the green sheets into the sintering material box and automatically stacking the sintering material boxes includes: after the box loading box is docked with the conveying material box, the material box clamping and lifting device lifts all n layers of empty sintering material boxes from the material bed, and the sintering material box conveying device moves horizontally from the box loading box to the conveying material box shell, and then the material box clamping and lifting device puts n layers of empty sintering material boxes onto the sintering material box conveying device, and then the material box clamping and lifting device lifts (n-1) layers of empty sintering material boxes, and the sintering material box conveying device moves the remaining 1 layer of empty sintering material boxes from the conveying material box shell to the box loading box, and then the sintering material box conveying device is lifted and lowered to load the green sheets into the sintering material boxes in the box loading box, and then the sintering material box conveying device moves the sintering material boxes containing the green sheets horizontally to the conveying material box. The material box is placed in the shell, and then the material box clamping and lifting device lowers the (n-1) layer of empty sintering material boxes to the top of the layer of sintering material boxes on the sintering material box conveying device, and then the material box clamping and lifting device lifts the (n-2) layer of empty sintering material boxes, and the sintering material box conveying device moves the 2 layers of sintering material boxes including 1 layer of empty sintering material boxes from the conveying material box shell to the box loading box, and the compacts are loaded into the empty sintering material boxes in the box loading box, and so on, until n layers of empty sintering material boxes are loaded with compacts in the box loading box and then moved to the conveying material box shell, and then the material box clamping and lifting device lifts the n layers of sintering material boxes loaded with compacts from the sintering material box conveying device, the sintering material box conveying device returns to the box loading box, and the material box clamping and lifting device lowers the n layers of sintering material boxes onto the material bed.
[0029] In one embodiment of the present invention, the rare earth permanent magnet intelligent production line also includes a glove box; the other end of the conveyor box is connected to the manual unloading glove box, and the glove box includes a glove box body, a fifth isolation valve, a discharge box and a tray transmission device.
[0030] The present invention also relates to a method for manufacturing rare earth permanent magnet materials, which is implemented using the above-mentioned rare earth permanent magnet intelligent production line, and the entire process from loading powder into the automatic magnetic field press to sintering the green compact is completed in isolation from the atmosphere. The manufacturing method includes: (1) automatically feeding the NdFeB alloy powder in the powder storage device into the mold cavity of the automatic magnetic field press, and automatically ejecting the green compact after magnetic field orientation molding and conveying it to the conveyor belt in front of the automatic magnetic field press; (2) the conveyor belt brings the green compact into a box located on the side of the automatic magnetic field press, and the robot in the box box puts the green compact into the sintering material box; (3) docking the conveying material box and the box box, opening the first isolation valve and the second isolation valve, and then by moving the sintering material box conveying device of the box box and lifting the material box clamping and lifting device of the conveying material box, Cooperate with the robot to complete loading the green sheets into the sintering box and stacking them in the conveying box; (4) After closing the first isolation valve and the second isolation valve, the conveying box is separated from the boxing box. After the conveying box carrying the sintering box containing the green sheets is separated from the boxing box, it is moved to the front of the vacuum sintering furnace provided with the third isolation valve. After the conveying box is docked with the vacuum sintering furnace, the third isolation valve and the second isolation valve are opened to convey the sintering box containing the green sheets in the conveying box to the vacuum sintering furnace. Then, the conveying box is separated from the vacuum sintering furnace, and the vacuum sintering furnace performs the vacuum sintering process; Before the conveying material box and the vacuum sintering furnace are separated, the second isolation valve and the third isolation valve are closed to keep the atmosphere in the conveying material box and the vacuum sintering furnace isolated from the atmosphere.
[0031] The manufacturing method also includes: after the vacuum sintering process is completed, the conveying material box and the vacuum sintering furnace are connected, and after the third isolation valve and the second isolation valve are opened, the sintering material box containing the sintered blanks is conveyed into the conveying material box, and after the third isolation valve and the second isolation valve are closed, the conveying material box and the vacuum sintering furnace are separated; the conveying material box is moved to the front of the discharge mechanism, and the second isolation valve is opened to move the sintering material box containing the sintered blanks in the conveying material box to the discharge mechanism, and then the empty sintering material box on the discharge mechanism is conveyed into the conveying material box; before the conveying material box is moved to the box loading box, the conveying material box and the loading box are connected, and the empty sintering material box is moved from the conveying material box to the box loading box to complete the process of magnetic field forming and vacuum sintering of rare earth permanent magnet materials; the automatic magnetic field press, the magnetic block conveying device and the box loading box constitute a closed space, and the protective gas is filled inside; from the time the pressed blank is loaded into the sintering material box to the end of vacuum sintering, the pressed blank is always isolated from the atmosphere.
[0032] The manufacturing method does not include an isostatic pressing process.
[0033] In the rare earth permanent magnet intelligent production line of the present invention, the rare earth permanent magnet material process from the alloy powder to the magnetic field forming of the sintered blank and the vacuum sintering is automatically completed under nitrogen protection or vacuum conditions, so that the rare earth permanent magnet raw materials that are very easy to oxidize are always isolated from the atmospheric environment, which is conducive to reducing the oxygen content in the material and further improving the performance of the rare earth permanent magnet material; in addition, the material preparation, boxing, furnace loading, material transportation between various processes, and the removal of sintered blanks in this process are completely completed in an automated form, which not only improves production efficiency, saves human resources, and reduces production costs, but also eliminates the uncertainty of manual operation, reduces the defective rate of products, and improves the stability of product quality. Under the same raw material composition and the same manufacturing process parameters, the oxygen content in the rare earth permanent magnet material manufactured by the technical solution of the present invention is reduced by about 200ppm, and the product defective rate caused in the process is reduced by about 30%.
[0034] The current vacuum sintering furnaces in the industry generally use a glove box structure and adopt manual operation to achieve protected feeding. In addition, most of them use a material fork device to move the material from the glove box to the material bed of the vacuum sintering furnace. When moving the material, the material fork of the cantilever structure will have a certain degree of shaking. The inventor found that in this production line, since two isolation valves are set between the vacuum sintering furnace and the conveying material box, if this type of vacuum sintering furnace is still used, the cantilever length of the material fork will need to be lengthened due to the large moving stroke, which is easy to cause the shaking to intensify. The compacts in the sintering material box are prone to produce micro defects in the shaking, which has a certain impact on the quality of the sintered rare earth permanent magnet material. The vacuum sintering furnace in the present invention includes a movable bottom plate assembly, and a roller is arranged on the bottom plate shell. The bottom plate assembly can be moved along the track on the inner wall of the furnace shell by the roller. After the vacuum sintering furnace is docked with the conveying material box, the bottom plate assembly moves into the conveying material box to carry the sintering material box containing the compacts in the conveying material box, and then returns to the vacuum sintering furnace with the sintering material box. The structure of the movable base plate assembly has stable transmission and well overcomes the above problems.
[0035] The existing technology was mainly developed around 2000. Although many improvements have been made subsequently, the market is in urgent need of solving the problems of unbalanced application of rare earth resources and tight supply of heavy rare earth elements dysprosium and terbium. To this end, the applicant has developed a new generation of process and production line equipment technology to improve the problems of the existing technology. This application is part of the new technology production line equipment, which mainly solves the following problems: 1. In the prior art, a box is set in front of each press, and then the boxes filled with green sheets are respectively transferred to the box for arrangement. A batch of green sheets in a vacuum sintering furnace must be docked with multiple mobile boxing boxes and inflated and deflated multiple times. Not only is the equipment complicated, but it also increases a lot of workload, which seriously increases the oxygen content of the green sheets. In fact, this structure cannot do without human participation and is not truly automatic. The conveyor belt of this application directly brings the green sheets into the boxing box, and uniformly loads the green sheets into the sintering box in the boxing box. The conveyor box and the boxing box are docked once to complete one batch of charges in the sintering furnace. Low oxygen content, nitrogen saving, simple and reliable operation, practical.
[0036] 2. The conveying material box of the present invention is docked with the box loading box, and is directly docked with the vacuum sintering furnace after being undocking with the box loading box. The empty sintering material box is transferred back to the box loading box through the conveying material box, realizing automatic operation.
[0037] 3. In the prior art, a carrier one is docked with the magnetic field press, and a carrier two is docked with the box loading box. The interface sizes of carrier one and carrier two are different, so carrier one cannot be docked with the glove box of the vacuum sintering furnace. In other words, the empty sintering boxes cannot be directly transferred to the magnetic field press. In the present invention, the compacts from multiple magnetic field presses are directly transferred to the box loading box. There is no need to transfer the sintering boxes to the magnetic field press. The process is short and simple, and the oxygen content is easy to control. The conveying box can be directly docked with the box loading box, the vacuum sintering furnace, and the discharging device. After the conveying box is docked with the discharging device, the sintering boxes are transferred to the discharging mechanism in layers, and the single-layer empty sintering boxes on the discharging mechanism are loaded into the conveying box and stacked, and then transferred back to the box loading box to load the compacts, thereby completing full automatic operation.
[0038] 4. The cartoning box in the production line involved in the present invention includes a cartoning box shell, a material box moving device, and a material picking mechanism; the material picking mechanism includes a manipulator, which is inverted on the upper part of the cartoning box and is also equipped with a visual system; the pressed blanks are transferred to the cartoning box, and the manipulator determines when to grab the pressed blanks and where to put them. BRIEF DESCRIPTION OF THE DRAWINGS
[0039] Figure 1 It is a schematic diagram of the main structure of an embodiment of the vacuum sintering furnace in the present invention.
[0040] Figure 2 It is a schematic diagram of the top structure of an embodiment of the vacuum sintering furnace in the present invention.
[0041] Figure 3 It is a side structural schematic diagram of an embodiment of the vacuum sintering furnace in the present invention.
[0042] Figure 4 It is a schematic diagram of the structural layout of an implementation method of the rare earth permanent magnet intelligent production line involved in the present invention.
[0043] Figure 5 It is a structural schematic diagram of an implementation mode of the automatic magnetic field press of the rare earth permanent magnet intelligent production line involved in the present invention. DETAILED DESCRIPTION
[0044] The embodiments of the present invention will be further described below in conjunction with the accompanying drawings.
[0045] like Figure 1 , Figure 2 and Figure 3 As shown, the vacuum sintering furnace 01 of the present invention comprises a furnace shell 1, a first isolation valve 2, a material moving device 3, a heating chamber 4 and a vacuum system 5; the first isolation valve 2 is connected to the front flange of the furnace shell; the heating chamber 4 is arranged in the furnace shell 1, and comprises a movable bottom plate assembly 6; the bottom plate assembly 6 comprises a sintering material box support 7, a heat insulation screen 8 and a bottom plate shell 9, and a roller 10 is arranged on the bottom plate shell 9, and the bottom plate assembly 6 can move along the track 11 on the inner wall of the furnace shell through the roller 10; the material moving device 3 comprises a moving rod 12, a sealing assembly 13 and a transmission device 14, the transmission device 14 is arranged outside the furnace shell 1, the sealing assembly 13 is connected to the furnace shell 1, and the transmission device 14 drives the moving rod 12 to pass through the sealing assembly 13 and enter the interior of the furnace shell 1; the moving rod 12 is connected to the bottom plate assembly 6, and drives the bottom plate assembly 6 to move. A heater 15 is arranged in the heating chamber 4.
[0046] The bottom plate assembly 6 further includes a heater 16 , which is disposed on the heat insulation screen 8 ; the material moving device has two moving rods 12 , and electrodes for energizing the heater 16 are disposed inside the moving rods 12 .
[0047] The vacuum sintering furnace 01 further includes an air-cooling heat exchange system 17 and an air charging system 18; the air-cooling heat exchange system 17 is arranged at the rear of the furnace shell 1, and the air inlet pipe of the air-cooling heat exchange system is connected to the furnace shell 1. The air-cooling heat exchange system includes a cooling fan and a heat exchanger. The air charging system 18 includes an air charging valve 19; after heating, the air charging valve 19 is opened to charge protective gas into the vacuum sintering furnace, and the cooling fan is started when the pressure in the furnace reaches the set value.
[0048] The heating chamber 4 also includes two side panel assemblies 20, which are respectively located at the left and right sides of the heating chamber 4; the outlet pipe 21 of the air-cooled heat exchange system is divided into two pipelines 22 before penetrating into the furnace shell, each pipeline 22 is provided with a valve 23, and the pipeline 22 passes through the furnace shell 1 and is respectively connected to the two side panel assemblies 20 of the heating chamber; the side panel assembly 20 includes a side panel outer shell, a heat insulation screen and a nozzle 24. The nozzle 24 is fixed on the side panel outer shell, and extends to the interior of the heating chamber 4 through the heat insulation screen of the side panel assembly 20. The two valves 23 are switched simultaneously or alternately. A pipeline 25 is provided on the outside of the side panel assembly 20, and the pipeline 25 is connected with the nozzle 24 and the pipeline 22. The gas flowing out of the outlet pipe 21 of the air-cooled heat exchange system is sprayed into the interior of the heating chamber 4 through the nozzle 24.
[0049] The heating chamber also includes a front cover assembly and an upper plate assembly.
[0050] In a preferred embodiment, the vacuum sintering furnace is a horizontal structure, the furnace shell is provided with a water cooling jacket, and the vacuum sintering furnace further comprises a cooling system, and the cooling system provides cooling for the furnace shell.
[0051] After the first isolation valve 2 is opened, the bottom plate assembly 6 can be moved to the outside of the vacuum sintering furnace 01; a movable conveying material box 26 is arranged outside the vacuum sintering furnace 01, and a second isolation valve 30 is arranged at one end of the conveying material box 26. The vacuum sintering furnace 01 can be docked with the conveying material box 26 arranged outside the vacuum sintering furnace through the first isolation valve 2; after the vacuum sintering furnace 01 is docked with the conveying material box 26, the first isolation valve 2 and the second isolation valve 30 are opened, and the bottom plate assembly 6 moves into the conveying material box 26 to carry the sintering material box 27 containing the pressed green sheet in the conveying material box, and then returns to the vacuum sintering furnace 01 with the sintering material box 27, and then the conveying material box 26 and the vacuum sintering furnace 01 are separated, and the vacuum sintering furnace 01 performs the vacuum sintering process. Before the conveying material box 26 and the vacuum sintering furnace 01 are separated, the first isolation valve 2 and the second isolation valve 30 are closed first.
[0052] After the vacuum sintering process is completed, the vacuum sintering furnace 01 is connected to the conveying material box 26, and the sintering material box 27 containing the sintered blanks is transferred from the vacuum sintering furnace 01 to the conveying material box 26 through the bottom plate assembly 6; before and after the vacuum sintering furnace 01 is connected to the conveying material box 26, the atmosphere in the conveying material box 26 and the vacuum sintering furnace 01 is kept isolated from the atmosphere.
[0053] In one embodiment of the present invention, the vacuum system 5 of the vacuum sintering furnace includes a mechanical vacuum pump 28 for directly exhausting to the atmosphere and a Roots vacuum pump 29 for further improving the vacuum degree in the furnace.
[0054] In a more preferred embodiment of the present invention, the vacuum sintering furnace also includes a sintering material box cover opening device, which includes a synchronous cover opening adjustment device on the upper part of the furnace shell and a cover opening assembly inside the furnace shell; when the vacuum sintering furnace is working, the cover opening assembly drives the box covers of the sintering material boxes loaded in the vacuum sintering furnace to open or close at the same time, and there are more than 3 layers of sintering material boxes loaded in the furnace, and each layer of sintering material boxes has more than 1 box cover.
[0055] The present invention also relates to a rare earth permanent magnet intelligent production line, such as Figure 4 As shown, the rare earth permanent magnet intelligent production line includes an automatic magnetic field press 31, a magnetic block conveying device 32, a box packing box 33, a conveying material box 26 and the above-mentioned vacuum sintering furnace 01. Figure 4 In the embodiment shown, the rare earth permanent magnet intelligent production line includes 4 vacuum sintering furnaces and 4 automatic magnetic field presses arranged side by side. One end of each automatic magnetic field press is respectively connected to the side of the magnetic block conveyor 32, and one end of the magnetic block conveyor 32 is connected to the box 33; the automatic magnetic field press 31, the magnetic block conveyor 32 and the box 33 constitute a closed space, which is filled with protective gas. The automatic magnetic field press 31 presses the rare earth alloy powder into a compact and then transfers it to the conveyor belt arranged in the magnetic block conveyor 32, and transfers the compact to the box 33 through the conveyor belt. The magnetic block conveyor 32 serves as a common transmission channel for the automatic magnetic field press, and transfers the compact pressed by each automatic magnetic field press to the box 33. A manipulator is arranged in the box, and the manipulator grabs the compact and puts it into the sintering material box placed in the box.
[0056] The box loading box 33 and the vacuum sintering furnace 01 are arranged side by side, and the conveying material box 26 can be moved to the opposite side of the box loading box 33 and the vacuum sintering furnace 01 by horizontal movement, and then the conveying material box 26 can be docked with the box loading box 33 and the vacuum sintering furnace 01 by longitudinal movement. A third isolation valve 34 is provided at one end of the box loading box 33. After the conveying material box 26 is docked with the box loading box 33, the second isolation valve 30 and the third isolation valve 34 are opened, and the space in the conveying material box 26 is connected with the space in the box loading box 33, and then the sintering material box can be moved between the box loading box 33 and the conveying material box 26. Before the box loading box 33 and the conveying material box 26 are separated, the second isolation valve 30 and the third isolation valve 34 are closed first to ensure that the box loading box 33 and the conveying material box 26 are sealed and airtight.
[0057] After being separated from the boxing box 33, the conveying box 26 carrying the sintering box containing the pressed green sheets is moved to the opposite side of the vacuum sintering furnace 01 and docked with the vacuum sintering furnace 01. After docking, the first isolating valve 2 and the second isolating valve 30 are opened to convey the sintering box containing the pressed green sheets in the conveying box 26 to the vacuum sintering furnace 01, and then the conveying box 26 is separated from the vacuum sintering furnace 01. Before the conveying box 26 and the vacuum sintering furnace 01 are separated, the first isolating valve 2 and the second isolating valve 30 are closed first to isolate the atmosphere in the conveying box 26 and the vacuum sintering furnace 01 from the atmosphere.
[0058] After the vacuum sintering process of the vacuum sintering furnace is completed, the sintering box containing the sintered blanks is transferred to the conveying box through the docking of the conveying box and the vacuum sintering furnace, and then the conveying box and the vacuum sintering furnace are separated; in the rare earth permanent magnet intelligent production line, magnetic field forming and vacuum sintering are automatically realized under nitrogen protection or vacuum conditions to produce rare earth permanent magnet sintered blanks.
[0059] The rare earth permanent magnet intelligent production line also includes a discharge mechanism 35, which is also arranged side by side with the box loading box 33 and the vacuum sintering furnace 01. The conveying box 26 can be moved horizontally to the opposite side of the discharge mechanism 35, and then docked with the discharge mechanism 35 by longitudinal movement. After docking, the second isolation valve 30 is opened, and the sintering box in the conveying box 26 can be conveyed to the discharge mechanism 35, or the sintering box on the discharge mechanism 35 can be conveyed to the conveying box 26.
[0060] like Figure 5 As shown, the automatic magnetic field press 31 includes a powder storage device 36, an automatic powder loading device 37, a powder loading box 38, a press frame 39, an upper press head assembly 40, a mold device 41, a lower press head assembly 42 and an electromagnetic orientation magnetic pole 43; the powder storage device 36 is located above the powder loading box 38; the automatic powder loading device 37 is arranged inside the powder loading box 38; the NdFeB alloy powder loaded in the powder storage device 36 is quantitatively loaded into the mold cavity of the mold device 41 through the automatic powder loading device 37; the upper press head assembly 40, the mold device 41, the lower press head assembly 42 and the electromagnetic orientation magnetic pole 43 are arranged in the press frame 39; the upper press head assembly 40 and the lower press head assembly 42 are respectively arranged above and below the mold device 41; there are two electromagnetic orientation magnetic poles 43, which are respectively located on both sides of the mold device 41. One side of the press frame 39 is connected to the powder loading box 38, and the other side is connected to the magnetic block conveying device 32, and a conveyor belt 44 is arranged in the magnetic block conveying device 32.
[0061] The mold device, the upper pressing head assembly, the lower pressing head assembly and the electromagnetic orientation magnetic poles realize bidirectional pressing of the powder in the mold cavity under magnetic field orientation to press the powder into a compact. The compact is ejected from the mold cavity and transferred to a conveyor belt.
[0062] The automatic magnetic field press is also provided with an electromagnetic orientation coil, which is sleeved on the outer side of the electromagnetic orientation magnetic pole.
[0063] exist Figure 5 In the embodiment shown, a wheel 45 is provided at the bottom of the press frame 39, which can move along the axis formed by the powder box 38, the press frame 39 and the magnetic block conveyor 32. A wheel 46 is also provided below the powder box 38, which can also move. A fourth isolation valve 47 is provided at the interface of the magnetic block conveyor 32 connected to the automatic magnetic field press 31.
[0064] When the automatic magnetic field press needs maintenance, the press frame can be disconnected from the magnetic block conveying device, and then the press frame and the powder box are moved away from the magnetic block conveying device; when the automatic magnetic field press needs to be restored to working state after maintenance, the press frame and the powder box are moved toward the magnetic block conveying device, and the connection between the press frame and the magnetic block conveying device is restored. When the automatic magnetic field press is disconnected from the magnetic block conveying device, it is necessary to close the fourth isolation valve first to make the magnetic block conveying device airtight, and continue to maintain the protective gas atmosphere in the enclosed space formed by the magnetic block conveying device, the box and the automatic magnetic field press in working state. The maintenance of the automatic magnetic field press includes replacing molds, overhauling and other work.
[0065] The magnetic block conveyor serves as a common conveying channel for the automatic magnetic field presses, and conveys the compacts pressed by each automatic magnetic field press into the box. Even if an automatic magnetic field press is undergoing maintenance or is restored to work after maintenance, the airtightness of the magnetic block conveyor is not affected, and it can still be used as a common conveying channel to provide automatic conveying of compacts for other automatic magnetic field presses, ensuring the normal operation of the rare earth permanent magnet intelligent production line.
[0066] The magnetic block conveying device includes a conveying device box; one end of the conveying device box is connected to the box packing box, and the side is connected to the automatic magnetic field press; a sensor for detecting whether there is a pressed blank at that position is arranged near the interface connecting the automatic magnetic field press and the conveying device box, and the sensor is used to control that the pressed blanks pressed by different automatic magnetic field presses do not collide with each other.
[0067] The box loading box includes a box loading box body and a sintering material box conveying device; one end of the box loading box body is connected to the third isolation valve, and the side is connected to the magnetic block conveying device; the conveyor belt in the magnetic block conveying device extends into the box loading box body; the manipulator and the sintering material box conveying device are arranged in the box loading box body; the manipulator grabs the compact conveyed into the box loading box body and puts it into the sintering material box on the sintering material box conveying device; after the box loading box and the conveying material box are docked, the sintering material box conveying device can reciprocate in the box loading box and the conveying material box. The sintering material box conveying device can move horizontally or up and down.
[0068] The discharging mechanism includes a material taking device, a fixed transfer assembly, a moving roller assembly and a fixed roller assembly; the material taking device is arranged on the fixed transfer assembly, and a conveying roller is also arranged on the fixed transfer assembly; after the conveying material box is docked with the discharging mechanism, the material taking device can reciprocate between the conveying material box and the discharging mechanism; the moving roller assembly is docked with the fixed transfer assembly, or with one or more fixed roller assemblies; when working, the material taking device enters the conveying material box, takes out the sintering material box and puts it on the conveying roller of the fixed transfer assembly, and the conveying roller of the fixed transfer assembly then conveys the sintering material box to the moving roller assembly; the moving moving roller assembly first docks with a group of fixed roller assemblies, and conveys the sintering material box to this group of fixed roller assemblies, and then the moving moving roller assembly docks with another group of fixed roller assemblies carrying empty sintering material boxes, and conveys the empty sintering material boxes to the moving roller assembly, and then the empty sintering material boxes are conveyed to the conveying material box through the moving roller assembly and the material taking device.
[0069] like Figure 3 As shown in the figure, the conveying material box 26 includes a conveying material box shell 48, a material box clamping and lifting device 49, a longitudinal moving device 50 and a transverse moving device 51; the second isolation valve 30 is connected to the conveying material box shell 48; the conveying material box shell 48 is installed on the guide rail 52 of the transverse moving device, and the conveying material box shell 48 together with the second isolation valve 30 moves longitudinally on the guide rail 52 of the transverse moving device to achieve the docking of the conveying material box with the box loading box, or with the vacuum sintering furnace.
[0070] After the packing box and the conveying box are docked, the process of automatically loading the compacts into the sintering boxes and automatically stacking the sintering boxes is completed through the reciprocating movement of the sintering box conveying device of the packing box and the lifting and lowering of the box clamping and lifting device in the conveying box, in coordination with the action of the robot.
[0071] In one embodiment of the present invention, the rare earth permanent magnet intelligent production line also includes a glove box; the other end of the conveyor box is connected to the manual unloading glove box, and the glove box includes a glove box body, a fifth isolation valve, a discharge box and a tray transmission device.
[0072] The present invention also relates to a method for manufacturing rare earth permanent magnet materials, which is implemented by using the above-mentioned rare earth permanent magnet intelligent production line, and the entire process from loading powder into the automatic magnetic field press to sintering the compact is completed under isolation from the atmosphere. The manufacturing method includes: (1) automatically feeding the NdFeB alloy powder in the powder storage device into the mold cavity of the automatic magnetic field press, and automatically ejecting the compact after magnetic field orientation molding and conveying it to the conveyor belt in front of the automatic magnetic field press; (2) the conveyor belt brings the compact into the box located on the side of the automatic magnetic field press, and the robot in the box is used to put the compact into the sintering box; (3) docking the conveying box and the box, opening the first isolation valve and the second isolation valve, and through the movement of the sintering box conveying device of the box and the lifting of the box clamping lifting device of the conveying box, and then cooperating with the robot to complete the loading of the compact into the sintering box and stacking in the conveying box; (4) After closing the first isolation valve and the second isolation valve, the conveying material box is separated from the box loading box. After being separated from the box loading box, the conveying material box carrying the sintering material box containing the pressed green sheets is moved to the front of the vacuum sintering furnace provided with the third isolation valve. After the conveying material box is docked with the vacuum sintering furnace, the third isolation valve and the second isolation valve are opened to convey the sintering material box containing the pressed green sheets in the conveying material box to the vacuum sintering furnace. Then, the conveying material box is separated from the vacuum sintering furnace, and the vacuum sintering furnace performs the vacuum sintering process. Before the conveying material box is separated from the vacuum sintering furnace, the second isolation valve and the third isolation valve are closed to keep the atmosphere in the conveying material box and the vacuum sintering furnace isolated from the atmosphere.
[0073] The manufacturing method further comprises: after the vacuum sintering process is completed, the conveying material box is docked with the vacuum sintering furnace, and after opening the third isolation valve and the second isolation valve, the sintering material box containing the sintered blank is conveyed into the conveying material box, and after closing the third isolation valve and the second isolation valve, the conveying material box and the vacuum sintering furnace are separated; the conveying material box is moved to the front of the discharging mechanism, the second isolation valve is opened to move the sintering material box containing the sintered blank in the conveying material box to the discharging mechanism, and then the empty sintering material box on the discharging mechanism is conveyed into the conveying material box; before moving the conveying material box to the box loading box, the conveying material box and the box loading box are docked, and the empty sintering material box is moved from the conveying material box to the box loading box, so as to complete the process of magnetic field forming and vacuum sintering of rare earth permanent magnet materials; The automatic magnetic field press, the magnetic block conveying device and the box packing box form a closed space filled with protective gas; from the time the compact is loaded into the sintering box to the end of vacuum sintering, the compact is isolated from the atmosphere.
[0074] The manufacturing method does not include an isostatic pressing process.
Claims
1. A vacuum sintering furnace, characterized in that: It includes a furnace shell, a first isolating valve, a material moving device and a heating chamber; the first isolating valve is connected to the front flange of the furnace shell; the heating chamber is arranged in the furnace shell, and includes a movable bottom plate assembly; the bottom plate assembly includes a sintering material box bracket, a heat insulation screen and a bottom plate shell, and rollers are arranged on the bottom plate shell, and the bottom plate assembly can be moved along the track on the inner wall of the furnace shell through the rollers; the material moving device includes a moving rod, a sealing assembly and a transmission device, the transmission device is arranged outside the furnace shell, the sealing assembly is connected to the furnace shell, and the transmission device drives the moving rod to pass through the sealing assembly and enter the inside of the furnace shell; the moving rod is connected to the bottom plate assembly to drive the bottom plate assembly to move.
2. The vacuum sintering furnace according to claim 1, characterized in that: The bottom plate assembly also includes a heater, which is arranged on the heat insulation screen; the material moving device has two moving rods, and electrodes for energizing the heater are arranged inside the moving rods and cooling water is passed through them.
3. The vacuum sintering furnace according to claim 1, characterized in that: The vacuum sintering furnace also includes an air-cooled heat exchange system and an air charging system; the air-cooled heat exchange system is arranged at the rear of the furnace shell, and the air inlet pipe of the air-cooled heat exchange system is connected to the furnace shell; the air-cooled heat exchange system includes a cooling fan and a heat exchanger; the air charging system includes an air charging valve; after the heating is completed, the air charging valve is opened to charge the vacuum sintering furnace with protective gas, and the cooling fan is started when the pressure in the furnace reaches the set value.
4. The vacuum sintering furnace according to claim 3, characterized in that: The heating chamber also includes two side panel assemblies, which are respectively located on the left and right sides of the heating chamber; the air outlet pipe of the air-cooled heat exchange system is divided into two pipelines before penetrating into the furnace shell, each pipeline is provided with a valve, and the pipelines pass through the furnace shell and are respectively connected to the two side panel assemblies of the heating chamber; the side panel assembly includes a side panel outer shell, a heat insulation screen and a nozzle; the nozzle is fixed on the side panel outer shell, and extends to the interior of the heating chamber through the heat insulation screen of the side panel assembly; the two valves are switched simultaneously or alternately.
5. The vacuum sintering furnace according to claim 1, characterized in that: After the first isolation valve is opened, the bottom plate assembly can be moved to the outside of the vacuum sintering furnace; a movable conveying material box is arranged outside the vacuum sintering furnace; The vacuum sintering furnace can be connected to the conveying box through the first isolation valve; after the vacuum sintering furnace is connected to the conveying box, the base plate assembly moves into the conveying box to carry the sintering box containing the compacts in the conveying box, and then returns to the vacuum sintering furnace with the sintering box. Then, the conveying box and the vacuum sintering furnace are separated, and the vacuum sintering furnace performs the vacuum sintering process.
6. The vacuum sintering furnace according to claim 1, characterized in that: The vacuum sintering furnace also includes a conveying material box; the conveying material box includes a conveying material box shell, a material box clamping and lifting device, a longitudinal moving device, a transverse moving device and a second isolating valve; the second isolating valve is connected to the conveying material box shell; the conveying material shell is installed on the transverse moving device, and the longitudinal moving device drives the conveying material box shell together with the second isolating valve to move on the transverse moving device; the conveying material box carrying the multi-layer sintering material box containing the pressed blank can be moved to the opposite side of the vacuum sintering furnace and docked with the vacuum sintering furnace, the first isolating valve and the second isolating valve are opened, and the multi-layer sintering material box in the conveying material box is conveyed into the vacuum sintering furnace, and then, the first isolating valve and the second isolating valve are closed, and the conveying material box is separated from the vacuum sintering furnace; after the vacuum sintering process of the vacuum sintering furnace is completed, the conveying material box and the vacuum sintering furnace are docked again, the first isolating valve and the second isolating valve are opened, and the sintering material box containing the sintered blank is conveyed into the conveying material box, and then, the first isolating valve and the second isolating valve are closed, and the conveying material box and the vacuum sintering furnace are separated.
7. The vacuum sintering furnace according to claim 5, characterized in that: After the vacuum sintering process is completed, the vacuum sintering furnace and the conveying material box are connected, and the sintering material box containing the sintered blanks is transferred from the vacuum sintering furnace to the conveying material box through the bottom plate assembly; before and after the vacuum sintering furnace and the conveying material box are connected, the atmosphere in the conveying material box and the vacuum sintering furnace is kept isolated from the atmosphere.
8. The vacuum sintering furnace according to claim 1, characterized in that: The vacuum sintering furnace also includes a material box cover opening device and a cover opening assembly; a sintering material box is placed on a sintering material box bracket; the cover opening assembly is located on the inner side of the heater and distributed on both sides of the sintering material box; the material box cover opening device is located on the upper part of the vacuum furnace shell, and a guide shaft passes through the vacuum furnace shell and the heat preservation screen of the heating chamber and is connected to the cover opening assembly; the material box cover opening device can drive the guide shaft to drive the cover opening assembly to move up and down.