Isostatic pressing forming equipment and high-pressure densification method for a magnesium oxide-based ceramic insulating tube

Abstract

The present invention discloses an isostatic pressing forming device and a high-pressure densification method for a magnesium oxide-based ceramic insulating tube, relating to the technical field of ceramic forming. In the present invention, four templates are movably installed in a pressurizing box. With the guidance and coordination of a moving and holding mechanism, after pressurization in the pressurizing box, the four templates can move synchronously, stably applying the same extrusion pressure to the raw materials in the forming cavity from the surrounding directions simultaneously, realizing the isostatic pressing forming of the ceramic insulating tube. At the same time, by opening a material discharging port above the forming cavity and cooperating with the column core to move up and down under the control of a first lifting mechanism, the isostatic pressing formed ceramic insulating tube can be lifted upward from the forming cavity, facilitating the staff to demold and take the material, and enabling continuous production, which improves the production efficiency of the isostatic pressing forming of the ceramic insulating tube to a certain extent.

Description

Technical Field

[0001] The present invention relates to the technical field of ceramic forming, and in particular to an isostatic pressing forming device and a high-pressure densification method for magnesium oxide-based ceramic insulating tubes. Background Art

[0002] Ceramic insulating tubes are widely used in industries such as electronics and power, aerospace, etc. due to their excellent insulation performance, high-temperature resistance characteristics, and good chemical stability. With the increasing demand for ceramic insulating tubes in various industries, the optimization and innovation of their production technology have become the key to the development of the industry. In the prior art, isostatic pressing forming equipment is usually used to process and produce ceramic insulating tubes.

[0003] Currently, when ceramic insulating tubes are produced by isostatic pressing forming, the commonly used method is to first fill the raw materials in a special isostatic pressing forming mold. After the raw materials are filled, the isostatic pressing forming mold is then put into a pressure chamber for isostatic pressing forming production. During the raw material filling process, manual meticulous operation is required to ensure that the raw materials are evenly distributed in the mold, which requires a high level of proficiency and concentration of the operator. A slight carelessness may result in uneven filling of the raw materials, affecting the quality of the product after isostatic pressing forming. Manual filling, mold loading, putting, and subsequent fishing and demolding result in a cumbersome production process. Each link takes a certain amount of time, lengthening the overall production cycle, leading to low production efficiency. Moreover, a large amount of manual raw material filling and disassembly of special molds result in high production costs, making it difficult to achieve continuous and efficient isostatic pressing production of ceramic insulating tubes.

[0004] Therefore, an isostatic pressing forming device and a high-pressure densification method for magnesium oxide-based ceramic insulating tubes are proposed to solve some problems existing in the above prior art. Summary of the Invention

[0005] The purpose of the present invention is to solve the drawbacks in the prior art that during the isostatic pressing forming production process of ceramic insulating tubes, manual raw material filling and mold disassembly and assembly result in a cumbersome forming production process, and inconvenient demolding and material taking, affecting production efficiency and production costs, and to propose an isostatic pressing forming device and a high-pressure densification method for magnesium oxide-based ceramic insulating tubes.

[0006] In order to solve the problems existing in the prior art, the present invention adopts the following technical solutions:

[0007] An isostatic pressing forming device for a magnesium oxide-based ceramic insulating tube, comprising a pressure box, in which a vertically arranged column core is slidably installed. Four templates evenly distributed around the column core are installed in the pressure box, and two adjacent templates are slidably connected. The upper and lower ends of the templates are respectively slidably connected to the inner end walls on the upper and lower sides inside the pressure box. The side of the numerous templates close to the column core in the counterclockwise direction is set as an arc wall. A discharge port corresponding to the column core is opened at the top of the pressure box, and a cover plate is sealed in the discharge port. An oil pipe is connected to the outer end wall of the pressure box. An outer frame is arranged below the pressure box, and an inner frame is installed in the outer frame. The lower end of the column core is vertically inserted into the inner frame. A first lifting mechanism for driving the inner frame to move up and down is installed in the outer frame.

[0008] Preferably, a moving and holding mechanism is installed in the pressure box. The moving and holding mechanism includes a first slide rail horizontally fixed on the end wall of each template away from the column core. A first sliding sleeve and a second sliding sleeve are slidably installed on the first slide rail. A second slide rail perpendicular to the first slide rail is horizontally fixed on the first sliding sleeve, and a third sliding sleeve fixedly connected to the inner end wall of the pressure box is slidably sleeved on the second slide rail.

[0009] Preferably, a gear column is rotatably installed in the pressure box. Horizontally rack bars symmetrically arranged about the center axis are meshed with the front and rear sides of the gear column, and vertically rack bars symmetrically arranged about the center axis are meshed with the left and right sides of the gear column. The horizontal rack bars and the vertical rack bars are in different planes. Connecting rods are connected to both the horizontal rack bars and the vertical rack bars. The front horizontal rack bar is fixedly connected to the second sliding sleeve on the left first slide rail through a connecting rod, the rear horizontal rack bar is fixedly connected to the second sliding sleeve on the right first slide rail through a connecting rod, the left vertical rack bar is fixedly connected to the second sliding sleeve on the rear first slide rail through a connecting rod, and the right vertical rack bar is fixedly connected to the second sliding sleeve on the front first slide rail through a connecting rod.

[0010] Preferably, a vertically arranged feeding channel is opened in the column core. A feeding port communicating with the feeding channel is opened above the column core. A feeding hose internally communicating with the feeding channel is installed at the bottom of the column core. A second lifting mechanism for driving the column core to move up and down is installed in the inner frame.

[0011] Preferably, there are two cover plates in total. A turning drive mechanism is connected between the two cover plates and the top of the pressure box. A groove adapted to the column core is opened on the cover plate. The first lifting mechanism includes a first toothed bar vertically fixed on the outer end wall of the inner frame. A first gear meshing with the first toothed bar is rotatably installed in the outer frame. A first motor is fixed in the outer frame, and the drive shaft of the first motor is in transmission connection with the first gear.

[0012] Preferably, the feeding port is opened on the cylindrical surface at the upper end of the feeding channel, and the thickness of the cover plate is set to be twice the inner diameter of the opening of the feeding port.

[0013] Preferably, the second lifting mechanism includes a sleeve fixedly installed inside the inner frame. A column core is slidably inserted into the sleeve. Tooth grooves are evenly distributed on the cylindrical surface of the column core from bottom to top. A second gear meshing with the tooth grooves is rotatably installed inside the sleeve. A second motor is fixed inside the inner frame, and the driving shaft of the second motor is in transmission connection with the second gear.

[0014] Preferably, a toothed disc is movably sleeved outside the column core. A vertically arranged chute is formed on the cylindrical surface of the column core. A slider adapted to the chute is fixed inside the toothed disc. A third gear meshing with the toothed disc is rotatably installed inside the inner frame. A first bevel gear is fixed on the driving shaft of the second motor. A second bevel gear meshing with the first bevel gear is fixed above the third gear. The bottom end of the column core is rotatably connected with a swivel joint, and the swivel joint is fixedly connected with a feeding hose. The tooth grooves are circumferentially formed on the cylindrical surface of the column core, and the depth of the chute is set to 1 / 2 of the depth of the tooth groove.

[0015] Preferably, the flipping drive mechanism includes two rotating shafts rotatably installed on the top of the pressurizing box. Two cover plates are respectively rotatably installed on the top of the pressurizing box through the corresponding rotating shafts. A fourth gear is fixed at the end of the rotating shaft. A second toothed rod meshing with the fourth gear is slidably installed on the top of the pressurizing box. A hydraulic push rod parallel to the second toothed rod is fixed on the top of the pressurizing box, and the telescopic end of the hydraulic push rod is fixedly connected with the second toothed rod.

[0016] Preferably, a high-pressure densification method for a magnesium oxide-based ceramic insulating tube, the high-pressure densification method includes the following steps:

[0017] S1. With the aid of the second lifting mechanism, drive the column core to move upward from bottom to top in the forming cavity formed by the cooperation of numerous templates and the arc-shaped wall, and through the communication of the feeding channel and the feeding port, as well as the rotation of the column core, evenly fill the magnesium oxide-based ceramic raw material from bottom to top in the forming cavity;

[0018] S2. After the top end of the column core rises to the top of the pressurizing box, control the left and right two cover plates to close in the discharging port through the flipping drive mechanism, and block the feeding port;

[0019] S3. Continuously supply the magnesium oxide-based ceramic raw material in the feeding channel. At the contact position between the feeding port and the groove, apply a lateral extrusion force on the cover plate, and cooperate with the restriction in the flipping drive mechanism to ensure the airtight stability at the discharging port;

[0020] S4. Continuously inject hydraulic oil into the pressurizing box through an oil pipe. Through the high-pressure push after hydraulic injection, drive the four templates to move and approach each other. With the coordinated guidance of the moving maintaining mechanism, make the four templates move synchronously, and apply a balanced and stable extrusion force synchronously from all around, and finally reduce the forming cavity to a cylindrical structure to complete the high-pressure densification extrusion molding of the magnesium oxide-based ceramic insulating tube.

[0021] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0022] 1. In the present invention, by movably installing four templates in the pressurizing box and with the guidance and coordination of the moving and holding mechanism, after pressurization in the pressurizing box, the four templates can move synchronously, stably applying the same extrusion pressure to the raw materials in the forming cavity from all around directions, realizing isostatic pressing forming of the ceramic insulating tube. At the same time, by opening the material discharging port above the forming cavity and cooperating with the lifting and moving of the column core under the control of the first lifting mechanism, the isostatically pressed ceramic insulating tube can be lifted upward from the forming cavity, facilitating the staff to demold and take the material, and enabling continuous production, which improves the production efficiency of isostatic pressing forming of ceramic insulating tubes to a certain extent;

[0023] 2. In the present invention, through the moving and holding mechanism coordinating the movement of the four templates, with the meshing of two transverse racks and the gear column, and the meshing of two longitudinal racks and the gear column, and cooperating with the sliding connection between adjacent two templates, the movement of the four templates in the front, back, left, and right directions is synchronous and the movement amplitude is consistent, thereby applying balanced and stable isostatic pressing extrusion to the raw materials in the forming cavity. After being pressurized, the four templates move synchronously towards the center position of the forming cavity, and can stably achieve high-pressure densification forming extrusion of the ceramic insulating tube;

[0024] 3. In the present invention, by opening the feeding channel in the column core and opening the feeding port above the column core, and cooperating with the meshing drive of the second gear and the tooth groove in the second lifting mechanism, when feeding raw materials, the column core can be driven to move upward in the forming cavity from bottom to top. With the sliding adaptation of the chute and the slider, the column core can also rotate during the driving process of the second lifting mechanism, more evenly transporting the ceramic raw materials into the forming cavity, which can improve the densification and stability of the device when isostatically pressing and producing ceramic insulating tubes to a certain extent;

[0025] 4. In the present invention, by symmetrically arranging the cover plate in the material discharging port, the opening and closing of the material discharging port are convenient. Cooperating with the lifting control of the column core, after the isostatic pressing forming of the ceramic insulating tube, it can be taken out of the forming cavity and separated, which is beneficial to further improving the convenience of demolding and taking the material. At the same time, by setting the thickness of the cover plate greater than the inner diameter of the feeding port, during the forming process, the continuous raw material feeding operation in the feeding channel will apply a lateral extrusion force on the cover plate at the contact position of the feeding port and the groove, and with the limitation in the flipping drive mechanism, it can effectively ensure the airtight stability at the material discharging port, which is beneficial to improving the sealing performance in the forming cavity after the material discharging port is closed. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of this application. The schematic embodiments of the present invention and their descriptions are used to explain the present invention and do not constitute an improper limitation to the present invention. In the drawings:

[0027] Figure 1 is the front elevation sectional view of the present invention;

[0028] Figure 2 is the perspective view of the present invention;

[0029] Figure 3 is the perspective view of the template of the present invention when not pressurized;

[0030] Figure 4 is the top plan sectional view of the pressure chamber of the present invention when not pressurized;

[0031] Figure 5 is the perspective view of the template of the present invention when pressurized;

[0032] Figure 6 is the top plan sectional view of the pressure chamber of the present invention when pressurized;

[0033] Figure 7 is the perspective view of the cover plate, groove and flipping drive mechanism of the present invention;

[0034] Figure 8 is the perspective view of the structure on the inner frame of the present invention;

[0035] Figure 9 is the top plan sectional view of the toothed disc and the third gear of the present invention;

[0036] Figure 10 is the perspective view of the second lifting mechanism of the present invention.

[0037] Reference numerals in the figures:

[0038] 1. Pressure chamber; 101. Column core; 102. Template; 103. Arc wall; 104. Discharging opening; 105. Cover plate; 106. Groove; 107. Oil pipe;

[0039] 2. First slide rail; 201. First sliding sleeve; 202. Second sliding sleeve; 203. Second slide rail; 204. Third sliding sleeve; 205. Gear column; 206. Transverse rack; 207. Longitudinal rack;

[0040] 3. Feeding channel; 301. Feeding port; 302. Feeding hose; 303. Adapter;

[0041] 4. Outer frame; 401. Inner frame; 402. First toothed bar; 403. First gear; 404. First motor;

[0042] 5. Sleeve; 501. Tooth groove; 502. Second gear; 503. Second motor; 504. Toothed disc; 505. Chute; 506. Slide block; 507. Third gear; 508. First bevel gear; 509. Second bevel gear;

[0043] 6. Rotating shaft; 601. Fourth gear; 602. Second toothed rod; 603. Hydraulic push rod. Specific embodiments

[0044] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

[0045] Embodiment: This embodiment provides an isostatic pressing forming device for a magnesium oxide-based ceramic insulating tube. Refer to Figure 1 - Figure 10 , specifically, it includes a pressurizing box 1. A vertically arranged core 101 is slidably installed in the pressurizing box 1. Four templates 102 evenly distributed around the core 101 are installed in the pressurizing box 1, and adjacent two templates 102 are slidably connected. The upper and lower ends of the template 102 are respectively slidably connected to the inner end walls on the upper and lower sides in the pressurizing box 1. The side of the numerous templates 102 close to the core 101 in the counterclockwise direction is set as an arc wall 103. A material discharging port 104 corresponding to the core 101 is opened at the top of the pressurizing box 1, and a cover plate 105 is blocked in the material discharging port 104. An oil pipe 107 is connected to the outer end wall of the pressurizing box 1. An outer frame 4 is arranged below the pressurizing box 1, and an inner frame 401 is installed in the outer frame 4. The lower end of the core 101 is vertically inserted into the inner frame 401.

[0046] When the device is in use, the four circumferentially distributed templates 102 and the arc wall 103 provided on their end walls cooperate with the inner end walls on the upper and lower sides of the pressurizing box 1 to form a relatively independent forming cavity. This forming cavity is used for the forming process of the magnesium oxide-based ceramic insulating tube. The core 101 is located at the center of this forming cavity. In the initial state, the internal space of this forming cavity is larger than the volume of the actually formed ceramic insulating tube. This makes the four circumferentially distributed templates 102 in a state of being away from each other in the initial state. The arc wall 103 is set to a radian of 1 / 4 circle. When the four templates 102 are extruded and synchronously approach the center position of the forming cavity, finally, the four arc walls 103 will cooperate with each other to form a complete cylindrical space. The magnesium oxide-based ceramic raw material is filled in the forming cavity. During the process of the forming cavity shrinking to a cylinder, the extrusion of the magnesium oxide-based ceramic raw material is completed, and it is densified and formed into a ceramic insulating tube.

[0047] A feeding channel 3 is vertically arranged inside the column core 101. A feeding port 301 communicating with the feeding channel 3 is arranged above the column core 101. A feeding hose 302 communicating with the inside of the feeding channel 3 is installed at the bottom of the column core 101. A second lifting mechanism for driving the column core 101 to lift up and down is installed inside the inner frame 401. The second lifting mechanism includes a sleeve 5 fixedly installed inside the inner frame 401. The column core 101 is slidably inserted into the sleeve 5. Tooth grooves 501 are evenly distributed on the cylindrical surface of the column core 101 from bottom to top. A second gear 502 meshing with the tooth grooves 501 is rotatably installed inside the sleeve 5. A second motor 503 is fixed inside the inner frame 401, and the drive shaft of the second motor 503 is in transmission connection with the second gear 502.

[0048] When using this device to produce ceramic insulating tubes, the oil pipe 107 is externally connected to a hydraulic oil pressurizing device, and the feeding hose 302 is externally connected to a magnesium oxide-based ceramic raw material supply device. The magnesium oxide-based ceramic raw material is composed of high-purity magnesium oxide powder, mixed with materials such as strontium titanate powder, yttrium oxide, silicon carbide, and alumina. Among them, yttrium oxide is used as a flux, which can effectively reduce the sintering temperature and improve the thermal shock resistance of the magnesium oxide-based ceramic insulating tube after sintering and forming. Silicon carbide and alumina are used as reinforcing agents, and they are evenly dispersed in the magnesium oxide matrix, which can improve the toughness and wear resistance of the ceramic insulating tube after sintering. During the production and processing process, the raw material supply device continuously transports the raw materials into the feeding channel 3 through the feeding hose 302, and then sprays them out through the feeding port 301 to fill the raw materials in the forming cavity.

[0049] In the initial state, the top end of the column core 101 is located below the forming cavity. During the raw material supply process, driven by the second lifting mechanism, along with the continuous supply of raw materials, the column core 101 will rise from bottom to top in the forming cavity. In this state, the second motor 503 is powered on and started, driving the second gear 502 connected to its drive shaft to rotate. Then, by means of the meshing of the second gear 502 and the tooth grooves 501, the column core 101 is driven to move upward. After the raw material supply is completed, the top end of the column core 101 passes through the material discharging port 104 and is located above the top of the pressure box 1. The upper cylindrical surface of the column core 101 is smooth, and the tooth grooves 501 are only arranged on the lower cylindrical surface of the column core 101. During the isostatic pressing forming process of the ceramic insulating tube, the tooth grooves 501 will not enter the forming cavity to ensure the smoothness and stability of the inner wall of the formed ceramic insulating tube.

[0050] In the specific implementation process, such as Figure 7As shown in the figure, there are two cover plates 105 in total. A flipping drive mechanism is connected between the two cover plates 105 and the top of the pressure box 1. A groove 106 adapted to the column core 101 is provided on the cover plate 105. The feeding port 301 is opened on the cylindrical surface at the upper end of the feeding channel 3. The thickness of the cover plate 105 is set to be twice the inner diameter of the opening of the feeding port 301. The flipping drive mechanism includes two rotating shafts 6 rotatably installed on the top of the pressure box 1. The two cover plates 105 are respectively rotatably installed on the top of the pressure box 1 through the corresponding rotating shafts 6. A fourth gear 601 is fixed at the end of the rotating shaft 6. A second toothed rod 602 meshing with the fourth gear 601 is slidably installed on the top of the pressure box 1. A hydraulic push rod 603 parallel to the second toothed rod 602 is fixed on the top of the pressure box 1, and the telescopic end of the hydraulic push rod 603 is fixedly connected to the second toothed rod 602.

[0051] When the device is in use, the rotation of the cover plate 105 can be controlled by the flipping drive mechanism to realize the opening and closing control of the discharging port 104. After the hydraulic push rod 603 is powered on and started, its telescopic end can move left and right. By moving the telescopic end of the hydraulic push rod 603, the second toothed rod 602 is controlled to move left and right. With the meshing of the second toothed rod 602 and the fourth gear 601, the fourth gear 601 is driven to drive the rotating shaft 6 to rotate, thereby realizing the flipping control of the left and right cover plates 105. Fourth gears 601 are fixed at both the front and rear ends of each rotating shaft 6, and a second toothed rod 602 is meshed outside each fourth gear 601. Through the meshing control of the fourth gears 601 and the second toothed rods 602 on the front and rear sides, the stability of the flipping opening and closing control of the left and right cover plates 105 can be effectively guaranteed. When the raw materials are filled inside the forming cavity, the flipping drive mechanism is started to control the left and right cover plates 105 to rotate synchronously and relatively, and fill the discharging port 104 to block the discharging port 104. With the grooves 106 provided on the left and right cover plates 105 and adapted to the outer end wall of the column core 101, the upper end of the column core 101 can be clamped in the grooves 106 on the left and right cover plates 105 to realize the stable holding of the upper end of the column core 101.

[0052] When the ceramic insulating tube is isostatically formed in the forming cavity, the supply operation of the magnesium oxide-based ceramic raw materials will be continuously maintained in the feeding channel 3. At the contact position between the feeding port 301 and the groove 106, a lateral pushing force is applied to the cover plate 105, and with the limitation in the flipping drive mechanism, the sealing stability at the discharging port 104 can be effectively guaranteed.

[0053] In the specific implementation process, such as Figure 3 - Figure 6As shown in the figure, a moving and holding mechanism is installed in the pressure box 1. The moving and holding mechanism includes a first slide rail 2 horizontally fixed on the end wall of each template 102 away from the column core 101. A first sliding sleeve 201 and a second sliding sleeve 202 are slidably installed on the first slide rail 2. A second slide rail 203 perpendicular to the first slide rail 2 is horizontally fixed on the first sliding sleeve 201. A third sliding sleeve 204 fixedly connected to the inner end wall of the pressure box 1 is slidably sleeved on the second slide rail 203. A gear column 205 is rotatably installed in the pressure box 1. Horizontally rack bars 206 symmetrically arranged about the center axis are engaged and connected to the front and rear sides of the gear column 205. Vertically rack bars 207 symmetrically arranged about the center axis are engaged and connected to the left and right sides of the gear column 205. The horizontally rack bars 206 and the vertically rack bars 207 are in different planes. Connecting rods are connected to both the horizontally rack bars 206 and the vertically rack bars 207. The front horizontally rack bar 206 is fixedly connected to the second sliding sleeve 202 on the left first slide rail 2 through a connecting rod. The rear horizontally rack bar 206 is fixedly connected to the second sliding sleeve 202 on the right first slide rail 2 through a connecting rod. The left vertically rack bar 207 is fixedly connected to the second sliding sleeve 202 on the rear first slide rail 2 through a connecting rod. The right vertically rack bar 207 is fixedly connected to the second sliding sleeve 202 on the front first slide rail 2 through a connecting rod.

[0054] When the device is in use, by virtue of the sliding connection between the first slide rail 2 outside each template 102 and the first sliding sleeve 201, and the sliding connection between the second slide rail 203 and the third sliding sleeve 204, the movement of each template 102 in the pressure box 1 is stable. Since the two horizontally rack bars 206 are engaged and connected to the front and rear sides of the gear column 205, and the two horizontally rack bars 206 are respectively connected to the left and right templates 102, the movement of the left and right templates 102 after being pressurized is synchronous, and the directions are opposite, and they will approach synchronously. Similarly, since the two vertically rack bars 207 are engaged and connected to the left and right sides of the gear column 205, and the two vertically rack bars 207 are respectively connected to the front and rear templates 102, the movement of the front and rear templates 102 after being pressurized is synchronous, and the directions are opposite, and they will approach synchronously. Also, since the two horizontally rack bars 206 and the two vertically rack bars 207 are both engaged with the gear column 205, and in combination with the sliding connection between adjacent two templates 102, the movement of the four templates 102 in the front, rear, left and right directions is synchronous. When one template 102 moves due to the extrusion and pushing of hydraulic oil, by virtue of the engagement between the gear column 205 and the horizontally rack bars 206 and the vertically rack bars 207, the templates 102 in the other directions will move uniformly and synchronously, and the movement amplitudes are the same, so as to apply balanced and stable isostatic extrusion molding to the raw materials in the molding cavity. The four templates 102 move synchronously towards the center position of the molding cavity after being pressurized, ensuring the stability of the isostatic molding of the ceramic insulating tube in the molding cavity.

[0055] During the actual operation process, when the material discharge port 104 is closed, the hydraulic oil pressurizing device transports high-pressure hydraulic oil to the pressurizing tank 1 through the oil pipe 107. Along with the high-pressure filling of the hydraulic oil, the four templates 102 are extruded and pushed, and synchronously move towards the center position in the forming cavity. When the four templates 102 move to the limit position, the raw materials are isostatically pressed and formed in the forming cavity. After the magnesium oxide-based ceramic insulating tube is isostatically pressed and formed, the staff controls the cover plate 105 to turn outwards through the flipping driving mechanism, and reopens the material discharge port 104. Then, the high-pressure injected hydraulic oil in the pressurizing tank 1 is pumped out. Along with the pumping out of the hydraulic oil filled during the isostatic pressing process, each template 102 is reset to the initial state. During this process, the arc-shaped wall 103 is separated from the outer end wall of the ceramic insulating tube, and the staff can take out the isostatically pressed magnesium oxide-based ceramic insulating tube through the opened material discharge port 104 above.

[0056] In the specific implementation process, as Figure 1 and Figure 8 shown, a first lifting mechanism for driving the inner frame 401 to move up and down is installed in the outer frame 4. The first lifting mechanism includes a first toothed rod 402 vertically fixed on the outer end wall of the inner frame 401. A first gear 403 meshing with the first toothed rod 402 is rotatably installed in the outer frame 4. A first motor 404 is fixed in the outer frame 4, and the driving shaft of the first motor 404 is in transmission connection with the first gear 403. When this device is used, during the process of taking out the formed ceramic insulating tube, after the arc-shaped wall 103 is separated from the outer end wall of the insulating ceramic tube, the ceramic insulating tube is still sleeved on the upper outer side of the column core 101. At this time, the staff can control the first lifting mechanism to start and continue to transport the column core 101 upwards. The first motor 404 is powered on and started, driving the first gear 403 connected to its driving shaft to rotate. By means of the meshing of the first gear 403 and the first toothed rod 402, the inner frame 401 is driven to rise in the outer frame 4. Since the lower end of the column core 101 is installed in the sleeve 5 fixed in the inner frame 401, the rising of the inner frame 401 will drive the column core 101 to rise further, thereby driving the ceramic insulating tube sleeved on the upper outer side of the column core 101 to move upwards, and moving through the material discharge port 104 to above the top of the pressurizing tank 1. Then, the staff controls the cover plate 105 to close in the material discharge port 104 again through the flipping driving mechanism. In this state, the ceramic insulating tube sleeved on the upper outer side of the column core 101 is located above the closed cover plate 105. Then, the staff drives the first lifting mechanism to start in the reverse direction and controls the column core 101 to move downwards. Since the bottom of the ceramic insulating tube will be blocked by the cover plate 105, while the descent of the column core 101 is not restricted, the ceramic insulating tube will be separated from the column core 101. After the column core 101 descends and retracts into the interior of the forming cavity, the isostatically pressed ceramic insulating tube is completely separated from the column core 101 and stays on the cover plate 105, which is more convenient for the staff to demold and take out the material.

[0057] During the operation of the device, four templates 102 are movably installed in the pressurizing box 1, and with the help of the guidance and coordination of the moving holding mechanism, the four templates 102 can move synchronously after the pressurization in the pressurizing box 1, and stably and synchronously apply the same extrusion pressure to the raw materials in the molding cavity from all directions, so as to realize the isostatic pressing of the magnesium oxide-based ceramic insulating tube. At the same time, the withdrawal port 104 is opened at the top of the pressurizing box 1, which is above the molding cavity, and the column core 101 can move up and down under the control of the first lifting mechanism, so that the ceramic insulating tube after isostatic pressing can be separated from the molding cavity upward through the withdrawal port 104, which is convenient for the staff to demold and take out the material. Compared with the prior art of filling the raw materials into a special isostatic pressing mold, and then putting the isostatic pressing mold into the pressurizing equipment for isostatic pressing production, the device can avoid the staff from assembling the mold before isostatic pressing, and disassembling the mold after isostatic pressing, and can realize rapid demolding and resetting, as well as continuous production, which can effectively improve the isostatic pressing production efficiency of magnesium oxide-based ceramic insulating tubes.

[0058] In the specific implementation process, Figure 1 and Figure 8 - Figure 10 As shown, a gear disc 504 is provided on the outer movable sleeve of the column core 101, a vertically arranged slide groove 505 is provided on the cylindrical surface of the column core 101, a slider 506 adapted to the slide groove 505 is fixed in the gear disc 504, a third gear 507 meshing with the gear disc 504 is rotatably installed in the inner frame 401, a first bevel tooth 508 is fixed on the driving shaft of the second motor 503, a second bevel tooth 509 meshing with the first bevel tooth 508 is fixed above the third gear 507, an adapter 303 is rotatably connected to the bottom end of the column core 101, and the adapter 303 is fixedly connected to the feed hose 302, a tooth groove 501 is arranged around the cylindrical surface of the column core 101, and the depth of the slide groove 505 is set to 1 / 2 of the depth of the tooth groove 501.

[0059] When the device is in use, the staff uses the second lifting mechanism to control the column core 101 to rise from bottom to top in the forming cavity. During the process of raw material supply, when the second motor 503 is powered on and starts, it will drive the first bevel gear 508 to rotate. By means of the meshing of the first bevel gear 508 and the second bevel gear 509, the third gear 507 will be driven to rotate synchronously. Then, by means of the meshing of the third gear 507 and the tooth disc 504, the tooth disc 504 is driven to rotate. Since the slider 506 fixed in the tooth disc 504 is slidably inserted into the chute 505 opened on the cylindrical surface of the column core 101, the slider 506 will drive the column core 101 to rotate during the rotation process. Furthermore, when the column core 101 rises from bottom to top in the forming cavity, it will also rotate, driving the feeding port 301 opened on the upper cylindrical surface of the column core 101 to move around in the forming cavity, and conveying the magnesium oxide-based ceramic raw materials to the forming cavity more evenly, which can improve the density and stability of the isostatic pressing of ceramic insulating tubes to a certain extent.

[0060] Since the feeding hose 302 is fixedly connected to the adapter 303, and the adapter 303 is rotationally connected to the bottom of the column core 101, the rotation of the column core 101 will not cause winding interference to the feeding hose 302. By arranging the tooth groove 501 around the lower cylindrical surface of the column core 101, and the opening depth of the tooth groove 501 is greater than the opening depth of the chute 505, the rotation of the column core 101 will not interfere with the meshing of the second gear 502 and the tooth groove 501, effectively ensuring the stability of the device during operation. During the actual use of the device, the lifting control of the column core 101 by the first lifting mechanism and the second lifting mechanism can be flexibly adjusted according to actual needs, effectively ensuring the flexibility of the device during actual use.

[0061] Specifically, the working principle and operation method of the present invention are as follows:

[0062] With the help of the second lifting mechanism, the column core 101 is driven to move upward from bottom to top in the forming cavity composed of numerous templates 102 and the arc-shaped wall 103. Through the connection of the feeding channel 3 and the feeding port 301, and the rotation of the column core 101, the magnesium oxide-based ceramic raw material is uniformly filled in the forming cavity from bottom to top. After the top of the column core 101 rises to the top of the pressurizing box 1, the left and right two cover plates 105 are controlled by the flipping drive mechanism to be closed in the discharging port 104, and the feeding port 301 is blocked. The supply operation of the magnesium oxide-based ceramic raw material is continuously maintained in the feeding channel 3. At the contact position between the feeding port 301 and the groove 106, a lateral pushing force is applied to the cover plate 105, and with the restriction in the flipping drive mechanism, the airtight stability at the discharging port 104 is ensured. Hydraulic oil is continuously injected into the pressurizing box 1 through the oil pipe 107. Through the high pressure generated after hydraulic injection, the four templates 102 are driven to move and approach each other. With the coordinated guidance of the moving maintaining mechanism, the four templates 102 move synchronously, and a balanced and stable extrusion force is applied synchronously from all around, finally reducing the forming cavity to a cylindrical structure, completing the high-pressure densification extrusion forming of the magnesium oxide-based ceramic insulating tube. After the ceramic insulating tube is extrusion formed, the cover plate 105 is turned outwards again, so that the discharging port 104 is opened. Along with the extraction of the hydraulic oil filled in the column core 101, each template 102 moves reversely to return to the initial state. Then the first lifting mechanism is started, driving the inner frame 401 to drive the column core 101 to continue moving upward, taking out the statically formed ceramic insulating tube from the forming cavity. Then the cover plate 105 is closed in the discharging port 104 again, and the first lifting mechanism is started reversely, driving the inner frame 401 to drive the column core 101 to descend. Blocked by the cover plate 105, the magnesium oxide-based ceramic insulating tube stays on the top of the cover plate 105. The staff collects the statically formed ceramic insulating tubes and then conducts sintering operations uniformly.

[0063] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution and inventive concept of the present invention, makes equivalent substitutions or changes, and all should be covered within the protection scope of the present invention.

Claims

1. An isostatic pressing forming device for a magnesium oxide-based ceramic insulating tube, comprising a pressure box (1), characterized in that: A vertical column core (101) is slidably installed in the pressure box (1). Four templates (102) evenly distributed around the column core (101) are installed in the pressure box (1), and two adjacent templates (102) are slidably connected to each other. The upper and lower ends of the template (102) are respectively slidably connected to the inner end walls on the upper and lower sides in the pressure box (1). The side of the numerous templates (102) close to the column core (101) in the counterclockwise direction is provided with an arc-shaped wall (103). A discharge port (104) corresponding to the column core (101) is opened at the top of the pressure box (1), and a cover plate (105) is plugged in the discharge port (104). An oil pipe (107) is connected to the outer end wall of the pressure box (1). An outer frame (4) is arranged below the pressure box (1), and an inner frame (401) is installed in the outer frame (4). The lower end of the column core (101) is vertically inserted into the inner frame (401). A first lifting mechanism for driving the inner frame (401) to move up and down is installed in the outer frame (4). A moving and holding mechanism is installed in the pressure box (1). The moving and holding mechanism includes a first slide rail (2) horizontally fixed on the end wall of each template (102) away from the column core (101). A first sliding sleeve (201) and a second sliding sleeve (202) are slidably installed on the first slide rail (2). A second slide rail (203) perpendicular to the first slide rail (2) is horizontally fixed on the first sliding sleeve (201), and a third sliding sleeve (204) fixed to the inner end wall of the pressure box (1) is slidably sleeved on the second slide rail (203). A gear column (205) is rotatably installed in the pressure box (1). Horizontally rack bars (206) symmetrically arranged about the center axis are engaged and connected to the front and rear sides of the gear column (205). Vertically rack bars (207) symmetrically arranged about the center axis are engaged and connected to the left and right sides of the gear column (205). The horizontally rack bars (206) and the vertically rack bars (207) are in different planes. Connecting rods are connected to both the horizontally rack bars (206) and the vertically rack bars (207). The front horizontally rack bar (206) is fixedly connected to the second sliding sleeve (202) on the left first slide rail (2) through a connecting rod. The rear horizontally rack bar (206) is fixedly connected to the second sliding sleeve (202) on the right first slide rail (2) through a connecting rod. The left vertically rack bar (207) is fixedly connected to the second sliding sleeve (202) on the rear first slide rail (2) through a connecting rod. The right vertically rack bar (207) is fixedly connected to the second sliding sleeve (202) on the front first slide rail (2) through a connecting rod. A feeding channel (3) vertically arranged is opened in the column core (101). A feeding port (301) communicating with the feeding channel (3) is opened above the column core (101). A feeding hose (302) internally communicating with the feeding channel (3) is installed at the bottom of the column core (101). A second lifting mechanism for driving the column core (101) to move up and down is installed in the inner frame (401). There are two cover plates (105) provided. A flipping drive mechanism is connected between the two cover plates (105) and the top of the pressurizing box (1). A groove (106) adapted to the column core (101) is formed on the cover plate (105). The first lifting mechanism includes a first toothed rod (402) vertically fixed on the outer end wall of the inner frame (401). A first gear (403) meshing with the first toothed rod (402) is rotatably installed in the outer frame (4). A first motor (404) is fixed in the outer frame (4), and the drive shaft of the first motor (404) is in transmission connection with the first gear (403).

2. The isostatic pressing forming equipment for a magnesium oxide-based ceramic insulating tube according to claim 1, wherein: The feeding port (301) is formed on the cylindrical surface at the upper end of the feeding channel (3). The thickness of the cover plate (105) is set to be twice the inner diameter of the opening of the feeding port (301).

3. An isostatic pressing forming device for a magnesium oxide-based ceramic insulating tube according to claim 1, characterized in that: The second lifting mechanism includes a sleeve (5) fixedly installed in the inner frame (401). The column core (101) is slidably inserted into the sleeve (5). Tooth grooves (501) evenly distributed are formed on the cylindrical surface of the column core (101) from bottom to top. A second gear (502) meshing with the tooth grooves (501) is rotatably installed in the sleeve (5). A second motor (503) is fixed in the inner frame (401), and the drive shaft of the second motor (503) is in transmission connection with the second gear (502).

4. An isostatic pressing forming device for a magnesium oxide-based ceramic insulating tube according to claim 3, characterized in that: A toothed disc (504) is movably sleeved outside the column core (101). A vertically arranged chute (505) is formed on the cylindrical surface of the column core (101). A slider (506) adapted to the chute (505) is fixed in the toothed disc (504). A third gear (507) meshing with the toothed disc (504) is rotatably installed in the inner frame (401). A first bevel gear (508) is fixed on the drive shaft of the second motor (503). A second bevel gear (509) meshing with the first bevel gear (508) is fixed above the third gear (507). The bottom end of the column core (101) is rotatably connected to a swivel joint (303), and the swivel joint (303) is fixedly connected to the feeding hose (302). The tooth grooves (501) are formed around the cylindrical surface of the column core (101). The depth of the chute (505) is set to be 1 / 2 of the depth of the tooth grooves (501).

5. An isostatic pressing forming device for a magnesium oxide-based ceramic insulating tube according to claim 1, characterized in that: The flipping drive mechanism includes two rotating shafts (6) rotatably installed on the top of the pressurizing box (1). The two cover plates (105) are respectively rotatably installed on the top of the pressurizing box (1) through the corresponding rotating shafts (6). A fourth gear (601) is fixed at the end of the rotating shaft (6). A second toothed rod (602) meshing with the fourth gear (601) is slidably installed on the top of the pressurizing box (1). A hydraulic push rod (603) parallel to the second toothed rod (602) is fixed on the top of the pressurizing box (1), and the telescopic end of the hydraulic push rod (603) is fixedly connected to the second toothed rod (602).

6. A high-pressure densification method for a magnesium oxide-based ceramic insulating tube, characterized in that, The high-pressure densification method is realized by using the isostatic pressing equipment for magnesium oxide-based ceramic insulating tubes as described in any one of claims 1-5. The high-pressure densification method includes the following steps: S1. With the aid of the second lifting mechanism, drive the column core (101) to move upward from bottom to top in the forming cavity constituted by the numerous templates (102) and the arc-shaped wall (103), and through the connection of the feeding channel (3) and the feeding port (301), as well as the rotation of the column core (101), uniformly fill the magnesium oxide-based ceramic raw material from bottom to top in the forming cavity; S2. After the top of the column core (101) rises to the top of the pressure box (1), control the left and right two cover plates (105) to close in the discharging port (104) through the flipping drive mechanism, and block the feeding port (301); S3. Continuously maintain the supply operation of the magnesium oxide-based ceramic raw material in the feeding channel (3), apply a lateral pushing force on the cover plate (105) at the contact position of the feeding port (301) and the groove (106), and cooperate with the restriction in the flipping drive mechanism to ensure the airtight stability at the discharging port (104); S4. Continuously inject hydraulic oil into the pressure box (1) through the oil pipe (107), drive the four templates (102) to move and approach each other through the high pressure after hydraulic injection, and with the coordinated guidance of the moving maintaining mechanism, make the four templates (102) move synchronously, apply an evenly stable extrusion pressure synchronously from all around, and finally reduce the forming cavity to a cylindrical structure to complete the high-pressure dense extrusion forming of the magnesium oxide-based ceramic insulating tube.

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