Variable-diameter self-aligning hydraulic extruder for rapid demolding of hot-pressed sintered material

Abstract

The variable-diameter automatic aligning hydraulic extruder comprises an automatic aligning mechanism, a variable-diameter pressure head mechanism, a telescopic mechanism and a guide device, the automatic aligning mechanism can automatically detect the axis deviation of a die and a pressure head through cooperation of a laser sensor and a motor control system, real-time adjustment is carried out through a precise algorithm, and the precision of the automatic aligning mechanism is improved. Therefore, precise butt joint of the die and the axis of the pressing head is achieved. The telescopic mechanism adopts a pull rod oil cylinder, stepless adjustment can be achieved according to the size requirements of different sintered bodies, it is ensured that the applied axial pressure is more uniform, and therefore the common pressure deviation problem in a traditional hydraulic extruding machine is avoided; according to the variable-diameter pressure head mechanism, the diameter of the pressure head can be automatically adjusted according to the requirements of a mold, it is ensured that the pressure head can be accurately matched with the mold even under the condition that the size change of a sintered body is large, and high cost and time consumption caused by frequent mold replacement are avoided.

Description

Technical Field

[0001] The invention relates to a precision hydraulic extruder device for demoulding, in particular to a diameter-variable automatic centering hydraulic extruder for rapid demoulding of hot-pressed sintered materials. Background Art

[0002] With the continuous development of industrial manufacturing technology, diamond carbide materials are widely used in many demanding fields such as mining, mechanical processing, and oil drilling due to their excellent hardness, wear resistance, and good toughness. However, despite the excellent physical properties of these materials, the demolding problem during the sintering process has become a key technical challenge in the manufacturing process. Traditional demolding methods have the following core problems: 1. Demolding stress concentration: During the sintering process, the interfacial stress generated by the cooling and shrinkage of the material often reaches as high as 300-500 MPa, which can cause localized wear of the mold. Traditional rigid molds, unable to effectively adjust pressure distribution, often suffer severe wear during repeated use, even significantly reducing the mold life.

[0003] 2. Dimensional adaptation limitations: Existing molds can only be adjusted within a certain range, typically accommodating dimensional fluctuations of ±2mm. Significant changes in sintered body size require the entire mold to be replaced, and the manufacturing cost of a single mold can reach 80,000 to 150,000 yuan, significantly increasing production costs.

[0004] 3. Poor force uniformity: Traditional hydraulic systems apply uneven force during demolding, especially during manual pressure adjustment, with deviations often exceeding 15%. This uneven force can cause cracks on the sintered body surface, ultimately affecting the quality of the finished product and even reducing the yield rate to around 73%.

[0005] 4. Disadvantages of Traditional Hydraulic Extruders: Existing hydraulic extruders typically utilize a fixed mold and constant-pressure demolding mode, which can lead to significant surface stress deviations in the sintered body. Circumferential pressure deviations can reach 15-20%, easily leading to edge cracking and even significant surface damage. Furthermore, since different sintered body sizes require custom molds of varying sizes, mold changes are cumbersome and time-consuming (ranging from 4-6 hours), impacting overall production efficiency. Summary of the Invention

[0006] In order to solve the shortcomings of traditional hydraulic extruders in mold adaptability, force uniformity and demolding accuracy, the present invention provides a variable diameter automatic centering hydraulic extruder for rapid demolding of hot pressed sintered materials. The present invention combines "variable diameter control" and "intelligent centering" to break through the technical bottleneck of traditional hydraulic extruders.

[0007] In order to solve the above technical problems, the technical solution adopted by the present invention is: a variable diameter automatic centering hydraulic extruder for rapid demolding of hot pressed sintered materials, comprising a blanking cabinet, a frame installed on the top of the blanking cabinet, the frame comprising a horizontal plate and a vertical plate connected together at the ends, the horizontal plate of the frame is installed on the top of the blanking cabinet, an automatic centering mechanism is installed on the top of the horizontal plate of the frame, and connecting holes are provided at corresponding positions between the automatic centering mechanism, the horizontal plate of the frame and the blanking cabinet; a fixed plate is installed on the upper side of the vertical plate of the frame, a telescopic mechanism is installed on the fixed plate, a variable diameter pressure head mechanism is installed at the end of the telescopic end of the telescopic mechanism, and the variable diameter pressure head mechanism comprises a motor box, the top of the motor box is connected to the end of the telescopic end of the telescopic mechanism, and the chassis The first motor is installed inside the casing, and the output end of the first motor is extended out of the bottom of the casing and is fitted with a small gear, and the small gear is meshed with a large gear. A guide plate is fitted at the center of the large gear, and a center rod is fitted at the center of the guide plate. A small piston cylinder is installed at the bottom of the motor casing, and the small piston cylinder is connected to a small piston rod. The bottom of the small piston rod is coaxially connected to the center rod. The end surface of the guide plate is provided with a plurality of guide holes, and pressure rods are inserted in the guide holes. The lower side wall of the center rod is hinged with a support rod respectively connected to each pressure rod. When the large gear rotates, each pressure rod is simultaneously moved closer to or away from the center rod under the action of the guide holes, and a metal sheet is installed on the bottom side wall of the pressure rod; a travel switch is also installed on the side wall of the frame vertical plate, and the first motor is electrically connected to a controller.

[0008] As a further limitation of the technical solution of the present invention, the automatic centering mechanism includes a workbench installed on the top of the frame cross plate, two second motors are installed on the workbench, the output end of the second motor is equipped with a fixture pinion, the fixture pinion is engaged with a fixture rack, the adjacent ends of the two fixture racks are respectively equipped with symmetrically arranged V-shaped chassis bayonet mounts, and FSR402 film pressure sensors are respectively installed on the adjacent sides of the V-shaped chassis bayonet mounts. A laser sensor is installed on the workbench located at the symmetry axis of the two V-shaped chassis bayonet mounts, and the laser sensor is located on the outside of the two V-shaped chassis bayonet mounts. The outer cover of the second motor, the fixture pinion and the fixture rack is provided with a chassis, the middle part of the chassis is open, and an STM32F1 single-chip microcomputer is also installed on the chassis. A button bracket vertical plate is installed on the workbench located at the edge of the chassis, and the laser sensor, the second motor, the STM32F1 single-chip microcomputer and the FSR402 film pressure sensor are all electrically connected to the controller.

[0009] As a further limitation of the technical solution of the present invention, the telescopic mechanism includes a tie rod cylinder and a guide shaft installed on a fixed plate. After the tie rod cylinder core inside the tie rod cylinder extends out of the fixed plate, it is connected to a pressure sensor and a pressure block mounting block arranged from top to bottom through a hydraulic cylinder transition joint. The pressure block mounting block is connected to the top of the motor box, and a stroke pressure plate is also installed on the side wall of the pressure block mounting block. A cylinder guide rod connecting plate is jointly installed between the tie rod cylinder core and the guide shaft located below the fixed plate.

[0010] As a further limitation of the technical solution of the present invention, metal sheet electrodes are respectively installed on the top and bottom of the pressure rod, wherein the metal sheet electrode on the top is connected to the control signal circuit of the pull rod cylinder.

[0011] As a further limitation of the technical solution of the present invention, the pressure sensor is connected to the hydraulic cylinder transition joint through a pressure sensor fixing plate.

[0012] As a further limitation of the technical solution of the present invention, the guide shaft is mounted on the fixing plate via a guide shaft fixing plate and a guide shaft fixing flange.

[0013] As a further limitation of the technical solution of the present invention, upper reinforcing plates are respectively installed at both ends of the top of the fixing plate, and one end of the upper reinforcing plate is fixed to the side wall of the rack vertical plate.

[0014] As a further limitation of the technical solution of the present invention, two supporting vertical plates are installed on the side walls of the rack vertical plate from top to bottom, and a sensor fixing frame is detachably connected between the two supporting vertical plates, and the travel switch is installed on the sensor fixing frame.

[0015] As a further limitation of the technical solution of the present invention, the large gear and the guide plate are connected via a key socket.

[0016] Compared with the prior art, the present invention has the following beneficial effects: 1. Intelligent centering technology: Through the cooperation of laser sensors and motor control systems, it can automatically detect the axis deviation between the mold and the indenter, and make real-time adjustments through a precise algorithm to achieve precise docking of the mold and indenter axes. The centering process of this invention not only improves accuracy, but also greatly improves production efficiency.

[0017] 2. Hydraulic uniform pressure technology: This device uses a tie rod cylinder and introduces a precision adjustment mechanism in the hydraulic system, which can achieve stepless adjustment according to the size requirements of different sintered bodies, ensuring that the applied axial pressure is more uniform, thereby avoiding the pressure deviation problem common in traditional hydraulic extruders.

[0018] 3. Variable-diameter pressure head design: The diameter of the pressure head can be automatically adjusted according to the mold requirements, ensuring that it can accurately fit the mold even when the sintered body size varies greatly. This innovative design can achieve stepless adjustment from 0 to 10 mm, greatly improving the adaptability of the equipment.

[0019] 4. Efficient mold adaptation: Unlike traditional molds, the indenter and automatic centering system used in this invention can adapt to over 95% of sintered body specifications, eliminating the high cost and time consumption of frequent mold changes. This significantly reduces mold manufacturing costs and production cycles.

[0020] 5. Intelligent control system: The present invention is equipped with high-precision pressure sensors and intelligent algorithms, which can monitor the stress changes during the mold demolding process in real time and automatically adjust the output pressure of the hydraulic system to ensure a more uniform stress distribution during the demolding process and avoid damage to the sintered body due to stress concentration.

[0021] The hydraulic extruder provided by this invention provides a more precise, efficient, and economical solution for the sintering and demolding of diamond carbide materials. Through an innovative combination of automatic centering, variable diameter control, and uniform hydraulic pressure, this device addresses the shortcomings of traditional hydraulic extruders in terms of mold adaptability, force uniformity, and demolding accuracy. The following is a detailed technical solution of this invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is one of the structural schematic diagrams of the variable diameter automatic centering hydraulic extruder used in the present invention.

[0023] Figure 2 This is the second structural diagram of the variable diameter automatic centering hydraulic extruder used in the present invention.

[0024] Figure 3 Schematic diagram of the variable diameter pressure head mechanism.

[0025] Figure 4 This is one of the structural diagrams of the automatic centering mechanism.

[0026] Figure 5 This is the second structural diagram of the automatic centering mechanism.

[0027] Figure 6 It is a schematic diagram of the connection between the telescopic mechanism and the variable diameter pressure head mechanism.

[0028] Figure 7 This is a schematic diagram of the telescopic mechanism installation.

[0029] Figure 8 This is a schematic diagram of the connection between the pressure rod, center rod and large gear.

[0030] Figure 9Schematic diagram of the connection between the pressure rod, support rod and support rod pin.

[0031] The following are marked in the figure: 1- workbench, 2- fixed plate, 3- button bracket vertical plate, 4- pressure sensor fixed plate, 5- guide shaft, 6- pressure sensor, 7- pressure block mounting block, 8- hydraulic cylinder transition joint, 9- oil cylinder guide rod connecting plate, 10- upper reinforcement plate, 11- tie rod oil cylinder, 12- tie rod cylinder core, 13- sensor fixing frame, 14- support vertical plate, 15- guide shaft fixed plate, 16- stroke pressure piece, 17- guide shaft fixing flange, 18- center rod, 19- Pressure rod, 20-support rod, 21-support rod pin, 22-guide plate, 23-small piston cylinder, 24-small piston rod, 25-, motor box, 26-chassis, 27-V-shaped chassis bayonet, 28-first motor, 29-pinion shaft, 30-large gear, 31-pinion, 32-frame, 33-second motor, 34-clamp pinion, 35-clamp rack, 36-key, 37-unloading cabinet, 38-travel switch, 39-laser sensor, 40- STM32F1 microcontroller, 41-metal sheet, 42- FSR402 thin film pressure sensor. DETAILED DESCRIPTION

[0032] The present invention will be further described below with reference to specific embodiments. Example 1

[0033] like Figure 1-8As shown, a variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressed sintered materials includes a blanking cabinet 37. A frame 32 is installed on the top of the blanking cabinet 37. The frame 32 includes a horizontal plate and a vertical plate connected together at the ends. The horizontal plate of the frame 32 is installed on the top of the blanking cabinet 37. An automatic centering mechanism is installed on the top of the horizontal plate of the frame 32. Connecting holes are opened at corresponding positions between the automatic centering mechanism, the horizontal plate of the frame 32 and the blanking cabinet 37; a fixed Plate 2, a telescopic mechanism is installed on the fixed plate 2, and a reducing head mechanism is installed at the end of the telescopic end of the telescopic mechanism. The reducing head mechanism includes a motor box 25, the top of the motor box 25 is connected to the end of the telescopic end of the telescopic mechanism, and a first motor 28 is installed inside the box 25. The output end of the first motor 28 extends out of the bottom of the box 25 and is covered with a small gear 31. The small gear 31 is connected to the output end of the first motor 28 through a small gear shaft 29. The small gear 31 is meshed with a large gear 30. The center of the gear 30 is provided with a guide plate 22, and the center of the guide plate is provided with a center rod 18. A small piston cylinder 23 is installed at the bottom of the motor box 25. The small piston cylinder 23 is connected to a small piston rod 24. The bottom of the small piston rod 24 is coaxially connected to the center rod 18. The end face of the guide plate 22 is provided with a plurality of guide holes, and a pressure rod 19 is inserted into each guide hole. The lower side wall of the center rod 18 is hinged with a support rod 20 between each pressure rod 19, and the two ends of the support rod 20 are connected to the center rod 18 by a support rod pin 21. The small piston rod 24 is hinged to the pressure rod 19. When the large gear 30 rotates, the small piston rod 24 rotates along with the small piston cylinder 23, controlling the pressure rod 19 to rotate along the guide plate 22. At the same time, the support rod 20 moves along the movable range of the small piston cylinder 23 to change the working range of the pressure rod 19, so that each pressure rod 19 simultaneously moves toward or away from the center rod 18 under the action of the guide hole. The bottom side wall of the pressure rod 19 is installed with a metal sheet 41; the side wall of the vertical plate of the frame 32 is also installed with a limit switch 38, and the first motor 28 is electrically connected to the controller. Under the setting of the metal sheets 41 on both sides of the pressure rod, when the metal sheets 41 on both sides of the pressure rod 19 contact the mold, the telescopic mechanism increases the downward pressure and begins to press down, and the hydraulic material falls into the discharge cabinet 37. After reaching the limit switch 38, the variable diameter automatic centering hydraulic extruder device stops working and resets.

[0034] Furthermore, the automatic centering mechanism includes a workbench 1 installed on the top of the horizontal plate of the frame 32, two second motors 33 are installed on the workbench 1, the output end of the second motor 33 is equipped with a clamp pinion 34, the clamp pinion 34 is engaged with a clamp rack 35, the adjacent ends of the two clamp racks 35 are respectively installed with symmetrically arranged V-shaped chassis bayonet 27, and the adjacent sides of the V-shaped chassis bayonet 27 are respectively installed with FSR402 film pressure sensors 42, and the workbench 1 located at the symmetric axis of the two V-shaped chassis bayonet 27 is installed with an excitation sensor. Optical sensors 39 and laser sensors 39 are located outside the two V-shaped chassis bayonet holes 27. The chassis 26, which covers the outer sides of the second motor 33, the fixture pinion 34, and the fixture rack 35, is open in the middle and is also mounted with an STM32F1 single-chip microcomputer 40. A button bracket stand 3 is mounted on the workbench 1 at the edge of the chassis 26. The laser sensor 39, the second motor 33, the STM32F1 single-chip microcomputer 40, and the FSR402 thin-film pressure sensor 42 are all electrically connected to the controller. The laser sensor 39 can sense whether a hydraulic object is placed. If a mold is placed in the center, the laser sensor 39 transmits a signal to the second motor 33 to control its movement. The second motor 33 then provides a power source for the fixture pinion 34, enabling fixed movement. When the second motor 33 receives a signal from the laser sensor 39, the fixture pinion 34 is connected to the power source of the second motor 33 via a shaft. When the power source drive shaft rotates, the fixture pinion 34 rotates accordingly, and its teeth engage with the fixture rack 35, interacting to push the rack to make linear motion, thereby driving the V-shaped chassis bayonet 27 to contract or expand. When the two diagonally opposite FSR402 film pressure sensors 42 both contact the mold, they transmit a signal to the motor 33, reducing the torque, thereby firmly fixing the mold in the center of the chassis workbench 1 axis. After the mold is firmly fixed in the center of the chassis workbench 1 axis, the STM32F1 microcontroller 40 transmits a signal to the press head motor box 22, causing it to start working.

[0035] Furthermore, the telescopic mechanism includes a tie rod cylinder 11 and a guide shaft 5 mounted on the fixed plate 2. The tie rod cylinder core 12 inside the tie rod cylinder 11 extends out of the fixed plate 2 and is connected to a pressure sensor 6 and a pressure block mounting block 7 arranged from top to bottom through a hydraulic cylinder transition joint 8. The pressure block mounting block 7 is connected to the top of the motor box 25. A stroke pressure plate 16 is also installed on the side wall of the pressure block mounting block 7. A cylinder guide rod connecting plate 9 is installed between the tie rod cylinder core 12 and the guide shaft 5 below the fixed plate 2. The guide device limits the movement trajectory of the piston rod to prevent deviation or jamming, thereby ensuring the accuracy and stability of the linear motion of the pressure head. The pressure sensor 6 and the tie rod cylinder 11 are both electrically connected to the controller. Metal electrodes are respectively installed on the top and bottom of the pressure rod 19, wherein the metal electrode on the top is connected to the control signal circuit of the tie rod cylinder 11. When the metal sheet electrode at the bottom of the pressure rod 19 in the variable diameter pressure head mechanism contacts the sintered material to be demoulded, the metal sheet electrode at the bottom of the pressure rod is connected to the metal sheet electrode at the top of the pressure rod. After the top and bottom metal sheet electrodes of the pressure rod are connected, the pull rod oil cylinder 11 stops the pressure head movement and the pull rod oil cylinder 11 is lifted (in the initial state, the top metal sheet electrode is energized, and the bottom and side are disconnected. When the bottom metal sheet electrode is connected, the pull rod oil cylinder 11 is lifted. After the centering is completed, the side is energized to short-circuit the bottom and top. At this time, it can be regarded as a separate control circuit for the side (equivalent to the bottom and top being a branch connected in parallel with the side (another branch)). With the first A motor 28 operates, rotating the small gear 31 and the large gear 30. The pressure rod 19 follows the trajectory of the guide hole in the guide plate 22. Simultaneously, the support rod 20 moves along the range of motion of the small piston cylinder 23, changing the total diameter of the pressure heads formed by the multiple pressure rods 19. After the metal sheet electrodes 41 on both sides of the pressure rods simultaneously contact the mold and reach the specified radius, they stop rotating, transmitting a signal to the tie rod cylinder 11 to begin pressing down. The tie rod cylinder 11 increases torque and applies hydraulic pressure downward. When the workpiece in the mold is transferred into the unloading cabinet 37, the metal sheet electrode 41 at the bottom of the pressure rod stops, and the tie rod cylinder 11 stops moving.

[0036] As a further limitation of the technical solution of the present invention, the pressure sensor 6 is connected to the hydraulic cylinder transition joint 8 through the pressure sensor fixing plate 4.

[0037] As a further limitation of the technical solution of the present invention, the guide shaft 5 is mounted on the fixing plate 2 via a guide shaft fixing plate 15 and a guide shaft fixing flange 17 .

[0038] As a further limitation of the technical solution of the present invention, upper reinforcing plates 10 are respectively installed at both ends of the top of the fixing plate 2 , and one end of the upper reinforcing plate 10 is fixed to the side wall of the vertical plate of the frame 32 .

[0039] As a further limitation of the technical solution of the present invention, two supporting vertical plates 14 are installed from top to bottom on the vertical plate side walls of the frame 32, and a sensor fixing frame 13 is detachably connected between the two supporting vertical plates 14, and the limit switch 38 is installed on the sensor fixing frame 13.

[0040] As a further limitation of the technical solution of the present invention, the large gear 30 and the guide plate 22 are connected via a key 36 .

[0041] The working process of the above-mentioned variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials is as follows: (1) After the mold is successfully fired, place it on the automatic centering chassis workbench 1 and start the motor switch.

[0042] (2) After the alignment is successful, a signal is transmitted to the tie rod cylinder 11 and the motor box 25. The pressure rod starts at the minimum radius, and the tie rod cylinder 11 starts to press down. During the downward movement of the pressure head, when the positive and negative electrodes of the pressure rod 19 are connected, the tie rod cylinder 11 is lifted, and the pressure head composed of multiple pressure rods 19 begins to change diameter. It moves downward into the mold hole and stops rotating when it reaches the set radius.

[0043] (3) When the metal sheet electrodes on both sides of the pressure rod contact the inner wall of the mold, the tie rod cylinder 11 begins to increase the torque and press down, and the workpiece officially begins to be demolded.

[0044] (4) When the travel switch is reached and the diamond carbide material is demoulded, the material enters the unloading cabinet 37 below, and all parts stop moving and reset.

[0045] The working principle of the variable diameter automatic centering hydraulic extruder of the present invention is as follows: 1. Automatic centering mechanism The automatic centering mechanism of the present invention utilizes a combination of a photoelectric sensor and a motor control system to automatically sense the mold's placement. When the mold is placed on the workbench, a laser sensor 39 detects contact between the mold and the chassis 26 and transmits this information to the motor control system. Upon receiving this signal, the motor control system activates the second motor 33, driving the fixture rack 35 to precisely adjust the position of the V-shaped chassis bayonet 27.

[0046] The coordination of the second motor 33 and the fixture rack 35 enables synchronous adjustment of the V-shaped bayonet on either side, precisely correcting the deviation between the mold axis and the ram axis. Alignment is performed gradually through small displacements until the mold axis and the ram axis are completely aligned. This ensures uniform pressure during hydraulic extrusion, avoiding the uneven pressure caused by axis deviation in traditional methods. After alignment is complete, that is, after the thin film pressure sensor makes contact, the motor continuously applies force to the bayonet with a low torque, preventing mold deviation caused by the radial force of the ram.

[0047] 2. Variable diameter pressure head mechanism The variable-diameter ram mechanism is a key innovation of this invention. Its core design allows it to automatically adjust the ram's diameter to suit different mold requirements. The variable-diameter ram is driven by a first motor 28, which drives a driving wheel. This driving wheel engages a driven wheel, which in turn drives the ram 19 along the guide hole. When the ram's diameter meets the mold's requirements—that is, when the metal sheets on both sides of the ram contact the mold's inner wall—the motor automatically stops.

[0048] This design can not only be adjusted according to molds of different specifications, but also ensure that the force applied during the demolding process is more uniform and precise by continuously adjusting the diameter of the pressure head, thus avoiding surface damage and cracks of the sintered body caused by uneven force in traditional hydraulic extruders.

[0049] 3. Hydraulic uniform pressure technology The hydraulic system of this invention utilizes a tie-rod cylinder 11, which precisely applies axial pressure through the linear motion of a piston rod within the cylinder. A hydraulic pump, driven by an electric motor, pushes high-pressure oil into the cylinder, controlling the direction and speed of the piston rod's movement, thereby achieving the push-pull action. The operating pressure and hydraulic flow of the hydraulic pump can be adjusted in real time based on actual needs, ensuring uniform pressure during the demolding process.

[0050] Unlike the constant-pressure demolding method used by traditional hydraulic extruders, the hydraulic pressure system of the present invention can adjust the pressure in real time through an intelligent control system according to the size and material of different sintered bodies, ensuring that the pressure fluctuations during the entire demolding process are controlled within an extremely low range, greatly reducing the damage to the sintered bodies caused by uneven pressure.

[0051] 4. Automatic control and intelligent system The automated control system of this invention utilizes high-precision sensors and intelligent algorithms to monitor and regulate the entire hydraulic extruder process. The system monitors the docking status between the ram and the die, hydraulic system pressure fluctuations, and various parameters during the demolding process in real time. If the system detects abnormal pressure fluctuations or misalignment between the die and ram, the intelligent control system automatically adjusts the motor speed, hydraulic system pressure, and ram diameter to ensure optimal operation at every stage of production.

[0052] The intelligent control system can also automatically select appropriate process parameters according to different production requirements, reducing the complexity and errors of manual operations, thereby improving production efficiency and product quality.

[0053] 5. Multifunctional adaptability and application scenarios The hydraulic extruder of this invention demonstrates excellent adaptability. Its variable-diameter ram design allows for rapid adaptation to molds of varying specifications, meeting the production requirements for sintered bodies of varying sizes and shapes. Furthermore, the design of the hydraulic uniform pressure system makes this device suitable not only for conventional cylindrical molds but also for complex, special-shaped molds.

[0054] Furthermore, the introduction of an intelligent centering system enables the equipment to quickly and automatically adjust to inaccurate mold placement or minor changes in mold specifications, ensuring precision and stability during every production process. This invention provides significant technical support for the sintering and demolding of specialized materials such as diamond carbide and ceramics, which require high-precision demolding. Example 2

[0055] Sintering demolding of diamond carbide materials Background and Requirements: During the sintering process of diamond carbide materials, mold release accuracy directly impacts the quality of the final product. Traditional hydraulic extruders often suffer from uneven force application, inaccurate centering, and poor mold adaptability. These issues can lead to cracks or defects on the sintered body surface, reducing product yield.

[0056] Device Setup and Operation Procedure: This embodiment uses the variable diameter automatic centering hydraulic extruder of the present invention to perform sintering and demolding of diamond carbide materials. The specific operation procedure is as follows: Mold Placement and Automatic Centering: After the sintered body is completed, it is first placed on the automatically centering base on the workbench. At this point, the laser sensor 39 detects contact between the mold and the base and transmits this information to the motor control system. The second motor 33 then starts, driving the clamp rack 35 and clamp pinion 34 for synchronous adjustment.

[0057] Automatic centering process: The movement of the rack enables precise adjustment of the V-shaped chassis bayonet 27. When the FSR402 thin film pressure sensors 42 on either side of the V-shaped chassis bayonet 27 simultaneously contact, a signal is transmitted to the motor 33, causing it to output a low torque to ensure that the mold axis and the indenter axis are completely aligned. The centering accuracy is monitored in real time by sensors in the system until the deviation is minimized. This process is automatically controlled by the motor, requiring no human intervention, greatly improving production efficiency and accuracy.

[0058] Hydraulic pressure and pressure head adjustment: After alignment is complete, the system activates the tie rod cylinder 11, which applies axial pressure to the mold. Due to the use of a variable diameter pressure head design, the diameter of the pressure head can be automatically adjusted according to the mold specifications, ensuring uniform pressure distribution during each pressure application process.

[0059] Demolding process: The hydraulic system controls the tie rod cylinder core 12 to perform precise linear motion, pushing the mold for demolding. During this process, when the metal sheet electrode at the bottom of the pressure rod 19 connects with the metal sheet electrode at the top of the pressure rod, the tie rod cylinder 11 stops pressing down and lifts upward to begin the centering process. When the metal sheets 41 on both sides of the pressure rod 19 contact the mold, the tie rod cylinder 11 increases torque and begins to press down. The hydraulic pump adjusts the pressure according to actual needs to ensure that there is no uneven stress distribution during the demolding process, avoiding the stress concentration phenomenon common in traditional hydraulic extruders.

[0060] End and mold removal: Once demolding is complete, the automatic centering device separates the mold and the pressing head, the hydraulic pressure system stops, and the equipment completes the demolding process. At this point, there are no obvious cracks on the sintered body surface, and there is no damage between the mold and the pressing head due to uneven pressure.

[0061] Results and Advantages: After demolding using the device of the present invention, the surface of the diamond carbide sintered body showed no cracks or defects, demonstrating excellent demolding results. Compared to traditional hydraulic extruders, the die life was extended by approximately 30%, and the yield rate increased by 12%. Thanks to its variable-diameter ram and automatic centering system, the device can accommodate sintered bodies of varying sizes and shapes, significantly improving production flexibility and versatility. Example 3

[0062] Sintering and demolding of ceramic materials Background and Requirements: Demolding accuracy is crucial during the sintering process of ceramic materials. Traditional hydraulic extruders are unable to cope with the high brittleness of ceramic materials, and mold breakage or cracks in the sintered body often occur during the demolding process.

[0063] Device setup and operation procedures: Mold Placement and Automatic Alignment: After the ceramic material is sintered, the mold is placed on the automatically aligning chassis workbench. The system automatically detects the mold's placement using a photoelectric sensor. The second motor 33 then begins operating, pushing the rack 35 for precise alignment, ensuring that the mold and the indenter's axis are fully aligned.

[0064] Hydraulic Pressure and Pressure Head Adjustment: Once the molds are docked, the hydraulic pump begins operating, and the tie rod cylinder 11 precisely controls the movement of the tie rod core 12, applying the appropriate demolding pressure to the ceramic material. The diameter of the pressure head is automatically adjusted through a motor-driven variable diameter design, ensuring uniform pressure application even with varying mold sizes.

[0065] Demolding and removal: After precise pressure application, the ceramic material is smoothly demolded. Because the hydraulic pressure system distributes pressure more evenly, no cracks form on the ceramic surface, preserving the integrity of the mold and significantly reducing damage to the sintered body caused by uneven pressure.

[0066] Results and Advantages: During the sintering and demolding process of ceramic materials, the hydraulic extruder device of the present invention achieved a demolding success rate of over 98%, a 15% improvement in demolding efficiency compared to conventional equipment. Furthermore, the ceramic materials experienced no cracks or breakage caused by uneven force application during demolding, significantly improving product quality.

Claims

1. A variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials, characterized in that: The invention comprises a feeding cabinet (37), wherein a frame (32) is installed on the top of the feeding cabinet (37), wherein the frame (32) comprises a horizontal plate and a vertical plate connected together at the ends, wherein the horizontal plate of the frame (32) is installed on the top of the feeding cabinet (37), and an automatic centering mechanism is installed on the top of the horizontal plate of the frame (32), and corresponding positions between the automatic centering mechanism, the horizontal plate of the frame (32) and the feeding cabinet (37) are provided with a connecting hole; a fixing plate (2) is installed on the upper side of the vertical plate of the frame (32), and a telescopic mechanism is installed on the fixing plate (2), and a reducing head mechanism is installed at the end of the telescopic end of the telescopic mechanism, and the reducing head mechanism comprises a motor box (25), the top of the motor box (25) is connected to the end of the telescopic end of the telescopic mechanism, and a first motor (28) is installed inside the box (25), and a pinion (31) is installed after the output end of the first motor (28) extends out of the bottom of the box (25). (31) is meshed with a large gear (30), a guide plate (22) is mounted at the center of the large gear (30), a center rod (18) is mounted at the center of the guide plate, a small piston cylinder (23) is mounted at the bottom of the motor box (25), the small piston cylinder (23) is connected to a small piston rod (24), the bottom of the small piston rod (24) is coaxially connected to the center rod (18), a plurality of guide holes are opened on the end face of the guide plate (22), and pressure rods (19) are inserted into the guide holes. A support rod (20) is hinged between the lower side wall of the center rod (18) and each pressure rod (19), and when the large gear (30) rotates, each pressure rod (19) is simultaneously moved closer to or away from the center rod (18) under the action of the guide hole. A metal sheet (41) is mounted on the bottom side wall of the pressure rod (19); a travel switch (38) is also mounted on the side wall of the vertical plate of the frame (32), and the first motor (28) is electrically connected to a controller.

2. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 1, characterized in that: The automatic centering mechanism includes a workbench (1) installed on the top of the horizontal plate of the frame (32), two second motors (33) are installed on the workbench (1), the output end of the second motor (33) is sleeved with a fixture pinion (34), the fixture pinion (34) is engaged with a fixture rack (35), the adjacent ends of the two fixture racks (35) are respectively installed with symmetrically arranged V-shaped chassis bayonet (27), the adjacent side surfaces of the V-shaped chassis bayonet (27) are respectively installed with FSR (402) film pressure sensors (42), and a laser sensor is installed on the workbench (1) located at the symmetry axis of the two V-shaped chassis bayonet (27). (39), the laser sensor (39) is located outside the two V-shaped chassis bayonet (27), the outer cover of the second motor (33), the fixture pinion (34) and the fixture rack (35) is provided with a chassis (26), the middle part of the chassis (26) is opened, and the chassis (26) is also installed with an STM32F1 single-chip computer (40), and the workbench (1) located at the edge of the chassis (26) is installed with a button bracket vertical plate (3), and the laser sensor (39), the second motor (33), the STM32F1 single-chip computer (40), and the FSR402 film pressure sensor (42) are all electrically connected to the controller.

3. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 1, characterized in that: The telescopic mechanism includes a pull rod cylinder (11) and a guide shaft (5) installed on a fixed plate (2). After the pull rod cylinder core (12) inside the pull rod cylinder (11) extends out of the fixed plate (2), it is connected to a pressure sensor (6) and a pressure block mounting block (7) arranged from top to bottom through a hydraulic cylinder transition joint (8). The pressure block mounting block (7) is connected to the top of the motor box (25). A stroke pressure plate (16) is also installed on the side wall of the pressure block mounting block (7). A cylinder guide rod connecting plate (9) is commonly installed between the pull rod cylinder core (12) located below the fixed plate (2) and the guide shaft (5). The pressure sensor (6) and the pull rod cylinder (11) are both electrically connected to the controller.

4. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 3, characterized in that: The top and bottom of the pressure rod (19) are respectively provided with metal sheet electrodes, wherein the metal sheet electrode at the top is connected to the control signal circuit of the pull rod cylinder (11).

5. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 3, characterized in that: The pressure sensor (6) is connected to the hydraulic cylinder transition joint (8) via the pressure sensor fixing plate (4).

6. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 3, characterized in that: The guide shaft (5) is mounted on the fixing plate (2) via the guide shaft fixing plate (15) and the guide shaft fixing flange (17).

7. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 3, characterized in that: Upper reinforcing plates (10) are respectively installed at both ends of the top of the fixed plate (2), and one end of the upper reinforcing plate (10) is fixed to the side wall of the vertical plate of the frame (32).

8. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 1, characterized in that: Two supporting uprights (14) are installed on the vertical side walls of the frame (32) from top to bottom, and a sensor fixing frame (13) is detachably connected between the two supporting uprights (14), and the travel switch (38) is installed on the sensor fixing frame (13).

9. The variable diameter automatic centering hydraulic extruder for rapid demoulding of hot pressing sintering materials according to claim 1, characterized in that: The large gear (30) and the guide plate (22) are sleeve-connected via a key (36).

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