A forming die for preventing cracking of an exhaust heat shield of an automobile

Abstract

The application discloses a kind of automobile exhaust system heat shield anti-cracking forming processing die, including upper die structure and lower die structure, upper die structure, it has the structure of being punched to metal plate, and it is installed in the output end of hydraulic equipment by bolt;Lower die structure, it has the slot type of metal plate stamping forming, it is installed on specified mounting seat by bolt, and it is set directly below upper die structure;When working, hydraulic equipment pushes upper die structure to be close to lower die structure and is punched, replenishment tank provides release agent and realizes lubrication release by limiting column and pipeline, and the heat insulating layer is formed by spraying material to spraying part, and the heat transfer of inductive heating part and other components of lower die structure is carried out during stamping process to improve the plasticity of metal plate.The die effectively reduces the risk of stamping cracking, reduces the friction force and stress concentration between the metal plate and the die, while shortening the production cycle, improving the production quality and efficiency of the heat shield, and has practical value and market prospect.

Description

Technical Field

[0001] This invention relates to the field of automotive parts manufacturing technology, specifically to a molding die for preventing cracking of a heat shield for an automotive exhaust system. Background Technology

[0002] The exhaust system heat shield is a crucial automotive component, serving several key functions: First, it provides protection, preventing heat generated by the exhaust system from damaging surrounding parts such as the fuel tank, brake lines, wiring, and plastic components. It also protects passengers by reducing heat transfer into the vehicle, lowering interior temperature, and mitigating the risk of fire. Second, it enhances vehicle performance by optimizing engine performance, maintaining stable engine compartment temperature, improving combustion efficiency, power output, and fuel economy, while reducing noise. Typically made of high-temperature resistant materials such as stainless steel, aluminum alloy, and ceramic fiber, it is installed in critical areas of the exhaust system. The installation location must consider heat insulation effectiveness, convenience, and impact on other components, ensuring adequate clearance from the exhaust system and a secure fit. In short, the automotive exhaust system heat shield is essential for protecting vehicle components, improving vehicle performance, and enhancing passenger comfort.

[0003] In the molding and processing of heat shields, molds are typically made using processes such as stamping, die casting, or injection molding. Among these, conventional manufacturers often choose stamping for automotive exhaust system heat shields. Stamping dies are tools used to press metal sheets into the shape of heat shields. Stamping dies usually consist of an upper die and a lower die. Through the action of a press, the sheet metal is plastically deformed in the die to form the desired shape. This process offers advantages such as high production efficiency, low cost, and high dimensional accuracy, making it suitable for mass production.

[0004] Several significant technical challenges exist in the current manufacturing process of heat shields for automotive exhaust systems. Firstly, the material faces stress concentration during the forming and stamping stages, particularly when passing through corners, sharp angles, or small-radius areas, where this stress concentration is particularly pronounced and can easily lead to material cracking. Furthermore, the friction between the metal sheet and the mold surface also subjects the material to greater tensile stress during stamping, further increasing the risk of cracking.

[0005] In addition to the problems mentioned above, existing heat insulation covers require additional heat insulation treatment after stamping. Specifically, a layer of heat insulation material (such as ceramic fiber, glass fiber, asbestos, etc.) needs to be added between the two layers of molded sheets. This step not only increases the complexity of the manufacturing process but also extends the production cycle.

[0006] To address this issue, a molding die for preventing cracking of the heat insulation cover in an automotive exhaust system is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a molding die for preventing cracking of automotive exhaust system heat shields, in order to solve the problems of stamping cracking and long production cycle of automotive exhaust system heat shield molding dies mentioned in the background art.

[0008] To achieve the above objectives, the present invention provides the following technical solution: a molding die for preventing cracking of a heat shield for an automotive exhaust system, comprising: The upper mold structure has a structure for stamping metal sheets, and it is bolted to the output end of the hydraulic equipment; The lower mold structure has a groove formed by stamping metal sheet, which is bolted to a designated mounting base and is located directly below the upper mold structure; The upper mold structure includes a stamping plate, on the upper surface of which a replenishing box is fixedly mounted. At least four limiting posts are provided on the periphery of the replenishing box between buffer springs, and all limiting posts are fixed to the upper surface of the stamping plate. Each limiting post has a transfer liquid chamber inside, and a positioning piston rod is slidably fixed inside the transfer liquid chamber by a spring. The lower end of the positioning piston rod slides through the transfer liquid chamber to the outside of the stamping plate, and a ball is rolled at the protruding end of the positioning piston rod. A portion of the limiting posts communicates with the interior of the replenishing box, and the sides of the other portion of the limiting posts are provided with spraying parts for spraying material onto the surface of the metal plate. The lower mold structure includes a lower mold, the surface of which has a stamping die groove, and the interior of the lower mold has symmetrically arranged hydraulic chambers on both sides of the stamping die groove. Multiple injection pipes and inlet pipes are respectively arranged on both sides of the upper part of the hydraulic chamber, near and away from the stamping die groove. The inlet pipes are correspondingly arranged with limiting posts and connected by retractable pipes. The injection pipes are evenly distributed on both sides of the stamping die groove, with one end of each injection pipe extending into the stamping die groove. Each injection pipe is equipped with a one-way valve. A piston lifting plate is slidably and sealed in the upper middle position of the hydraulic chamber. The upper surface of the piston lifting plate... A hydraulic spring and a telescopic rod are fixedly and movably installed at the center position. Multiple induction heating elements are fixedly installed on the lower surface of the piston lifting plate. A heat-conducting seat is fixedly installed at the bottom of the hydraulic chamber directly below the induction heating elements. An induction coil is sleeved between the induction heating elements and the heat-conducting seat. The side of the heat-conducting seat near the stamping die groove is fixed to an isolation heat-conducting frame. A heat-conducting support is integrally installed on the surface of the isolation heat-conducting frame facing the stamping die groove. The extension end of the support extends into the interior of the heat-conducting cavity and into the flat groove opened along the path at the opening of the stamping die groove, and makes contact with the heat-conducting material inside the heat-conducting cavity and the contact heat plate fixed in the flat groove for heat conduction.

[0009] Preferably, the upper mold structure further includes an assembly template. The assembly template has flanges integrally formed at the center of both its upper and lower surfaces for connection, and these flanges are respectively connected and fixed to the hydraulic equipment and the stamping part. The lower surface of the stamping part has a pre-set stamping pattern integrally formed. The assembly template has two rows of smooth, through-holes equidistantly spaced on both sides of the flanges. Each lifting hole has a corresponding buffer spring at its lower end. The buffer spring consists of a spring and a limiting slide rod. The spring is movably positioned between the assembly template and the stamping plate. The limiting slide rod is inserted at the center of the spring, with its lower end fixed to the stamping plate and its upper end slidably inserted into the lifting hole of the assembly template. A nut limits the upper end of the limiting slide rod as it passes through the lifting hole. The stamping plate has the same plate shape as the assembly template. Through-holes for limiting the lifting and sliding of the stamping part are formed at the center of both the stamping plate and the material replenishment box.

[0010] Preferably, an assembly is fixedly provided at the center position of the bottom of the lower mold.

[0011] Preferably, the telescopic rod is located at the center of the hydraulic spring, and the upper ends of both the hydraulic spring and the telescopic rod are fixed above the interior of the hydraulic chamber.

[0012] Preferably, the heat-conducting base has a heat-conducting core inside, and the core and the induction heat element are connected in an interlocking structure.

[0013] Preferably, initially, neither the induction heating element nor the heat-conducting base is within the loop of the induction coil, and the energized ends of the induction coil extend out of the lower mold after insulation and isolation, and are connected to external electrical control equipment.

[0014] Preferably, the heat-conducting isolation frame consists of an isolation sleeve and a heat-conducting core material fixed inside the isolation sleeve, wherein the isolation sleeve is fixedly disposed inside the lower mold, and one end of the heat-conducting core material is connected to the core inside the heat-conducting base.

[0015] Preferably, the heat conduction cavities are spaced apart and located directly below the stamping die groove inside the lower mold, and the heat conduction cavities are arranged to partially surround the tube diameter of the stamping die groove.

[0016] Compared with the prior art, the beneficial effects of the present invention are: This invention, through the arrangement of an assembly template, buffer spring, stamped part, stamping plate, replenishment box, limiting column, transfer liquid chamber, positioning piston rod, lower mold, assembly parts, hydraulic chamber, liquid inlet pipe, liquid injection pipe, stamping die groove, piston lifting plate, hydraulic spring, telescopic rod, induction heating element, heat conducting seat, insulating heat conducting frame, contact heat plate, and induction coil, allows the stamping process to utilize the stamping pressure to force the release agent inside the limiting column into the hydraulic chamber, causing the piston lifting plate inside the hydraulic chamber to move along the inner wall of the hydraulic chamber. During the downward movement, it works in conjunction with the induction coil to heat the induction heating element, and conducts the heat inside the induction heating element to the heat conducting seat, insulating heat conducting frame, and contact heat plate. This achieves heating of the metal plate and stamping die groove. Simultaneously, during stamping, the release agent can enter the interior of the stamping die groove and form a lubricating film at the contact interface between the metal plate and the stamping die groove. Based on the above design, not only can the heat be heated during the stamping process, but also the release agent can enter the interior of the stamping die groove and form a lubricating film at the contact interface between the metal plate and the stamping die groove. Heating the metal sheet significantly improves its plasticity and reduces internal stress caused by excessive material rigidity during stamping. This is especially beneficial in the forming of complex shapes, such as the curved parts and edges of heat shields. Localized heating allows the metal sheet to better adapt to changes in the mold shape, further reducing stress concentration and the possibility of cracking, thus improving product quality stability. Furthermore, the use of a release agent greatly reduces the friction between the metal sheet and the mold. During stamping, the reduced friction significantly lowers the tensile stress on the metal sheet. When the metal sheet undergoes plastic deformation in the mold, especially in areas prone to stress concentration such as corners, sharp angles, or small-radius areas, the reduced additional tensile stress due to friction effectively prevents cracking caused by excessive stress. The lubricating effect of the release agent also makes the deformation of the metal sheet in the mold smoother, improving forming quality and product yield. This invention, through the arrangement of a stamping plate, limiting column, transfer liquid chamber, positioning piston rod, spraying part, lower mold, assembly parts, hydraulic chamber, liquid inlet pipe, liquid injection pipe, stamping mold groove, heat conduction cavity, piston lifting plate, hydraulic spring, telescopic rod, induction heat element, heat conduction seat, isolation heat conduction frame, and induction coil, can spray specific materials onto the surface of a metal plate during the stamping process. These materials will form a heat insulation layer on the surface of the metal plate during the subsequent heating process, eliminating the need for additional heat insulation treatment after stamping in traditional processes. This innovative design greatly shortens the production cycle and improves production efficiency. In actual production, there is no need to transfer the stamped parts to other equipment or processes for heat insulation treatment, reducing time waste and operational complexity in intermediate links. At the same time, the simultaneous spraying and stamping can better ensure the bonding strength and uniformity of the heat insulation layer and the metal plate, improving the overall performance and quality of the product. This invention, through the design of the positioning piston rod, avoids damage to the metal sheet caused by excessive instantaneous impact force from the upper die. Simultaneously, the rolling ball design of the positioning piston rod and its accurate positioning function ensure the precision of the stamping position. During the stamping process, the metal sheet can be evenly stressed, reducing the risk of stress concentration and cracking caused by uneven local stress. Accurate positioning also improves the precision and consistency of product dimensions, reducing the scrap rate. Attached Figure Description

[0017] Figure 1 This is a three-dimensional structural view of the present invention; Figure 2 This is a structural breakdown diagram of the present invention; Figure 3 This is a cross-sectional view of the structure of the present invention; Figure 4 This is a cross-sectional view and a partially enlarged view of the stamping plate and its connecting structure of the present invention; Figure 5 This is an exploded view of the lower mold structure of the present invention; Figure 6 These are multiple cross-sectional views of the lower mold of the present invention; Figure 7 This is a schematic diagram of the internal structure of the lower mold of the present invention. Figure 1 ; Figure 8 This is a schematic diagram of the internal structure of the lower mold of the present invention. Figure 2 .

[0018] In the picture: 1. Upper mold structure; 11. Assembly template; 111. Buffer spring; 112. Stamped part; 12. Stamping plate; 121. Material replenishment box; 122. Limiting post; 1221. Transfer liquid chamber; 1222. Positioning piston rod; 1223. Painted part; 2. Lower mold structure; 21. Lower mold; 211. Assembly parts; 212. Hydraulic chamber; 2121. Liquid inlet pipe; 2122. Liquid injection pipe; 213. Stamping mold groove; 2131. Heat conduction cavity; 22. Piston lifting plate; 221. Hydraulic spring; 222. Telescopic rod; 223. Induction heating element; 224. Heat conduction base; 225. Insulating heat conduction frame; 226. Contact heat plate; 227. Induction coil. Detailed Implementation

[0019] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0020] Please see Figures 1 to 8 This invention provides a technical solution for forming a crack-resistant mold for a heat shield in an automotive exhaust system: A mold for forming and processing a crack-resistant heat shield for an automotive exhaust system, comprising: The upper mold structure 1 has a structure for stamping metal plates, and it is installed at the output end of the hydraulic equipment by bolts; The lower mold structure 2 has a groove formed by stamping a metal sheet, which is bolted to a designated mounting base and is located directly below the upper mold structure 1.

[0021] The upper mold structure 1 includes an assembly template 11. Flanges for connection are integrally provided at the center of both the upper and lower surfaces of the assembly template 11, and are respectively connected and fixed to the hydraulic equipment and the stamping part 112 via the flanges. A pre-set stamping pattern is integrally provided on the lower surface of the stamping part 112. Two rows of smooth, through-holes are equidistantly provided on both sides of the flanges of the assembly template 11. A buffer spring 111 is provided at the lower end of each lifting hole. The buffer spring 111 consists of a spring and a limiting slide rod. The spring is movably positioned between the assembly template 11 and the stamping plate 12. The limiting slide rod is inserted at the center of the spring, with its lower end fixed to the stamping plate 12 and its upper end slidably inserted into the lifting hole of the assembly template 11. A nut is used to limit the limiting slide rod at the upper end where it passes through the lifting hole. The stamping plate 12 has the same plate shape as the assembly template 11, and a replenishment box 121 is fixedly provided on the upper surface of the stamping plate 12. Both the stamping plate 12 and the replenishment box 121 have through holes at their center for limiting the lifting and sliding of the stamped part 112. The replenishment box 121 stores a specified release agent. At least four limiting posts 122 are provided on the periphery of the replenishment box 121 between the buffer springs 111. The limiting posts 122 are all fixed to the upper surface of the stamping plate 12. Each limiting post 122 has a transfer liquid chamber 1221 inside. A positioning piston rod 1222 is provided inside the transfer liquid chamber 1221 by spring sliding limitation. The lower end of the positioning piston rod 1222 slides out of the transfer liquid chamber 1221 to the outside of the stamping plate 12. A ball is rolled at the protruding end of the positioning piston rod 1222 for easy movement. The limiting posts 122 in the same row as the buffer springs 111 are connected to the inside of the replenishment box 121 by a one-way valve. A one-way output interface is provided on the side and is fixedly connected to a retractable pipeline through the interface.

[0022] The lower mold structure 2 includes a lower mold 21. An assembly 211 is fixedly installed at the center of the bottom of the lower mold 21. A stamping die groove 213 is formed on the surface of the lower mold 21 facing the upper mold structure 1, which is used for stamping the stamped part 112. Hydraulic chambers 212 are symmetrically formed on both sides of the stamping die groove 213 inside the lower mold 21. Multiple injection pipes 2122 and inlet pipes 2121 are respectively formed on the upper sides of the hydraulic chambers 212, near and away from the stamping die groove 213. The inlet pipes 2121 are correspondingly arranged with the limiting post 122 and connected through a retractable pipe, thereby controlling the flow of hydraulic fluid into the hydraulic chambers 212. The internal fluid replenishment system 12 has fluid injection pipes 2122 evenly distributed on both sides of the stamping die groove 213, with one end of each pipe extending into the stamping die groove 213. Each pipe is equipped with a one-way valve opening into the stamping die groove 213. A piston lifting plate 22 is slidably and sealed in the upper middle position inside the hydraulic chamber 212. A retractable hydraulic spring 221 and a telescopic rod 222 are movably and fixedly installed at the center of the upper surface of the piston lifting plate 22, with the telescopic rod 222 positioned at the center of the hydraulic spring 221. The upper ends of both the hydraulic spring 221 and the telescopic rod 222 are fixed inside the hydraulic chamber 212. Above, multiple heat-insulating threaded mounting seats are symmetrically fixed on the lower surface of the piston lifting plate 22, and are connected to the induction heating element 223 through the threaded mounting seats. The induction heating element 223 is made of metal, and a heat-conducting seat 224 is fixedly installed at the bottom of the hydraulic chamber 212 directly below it. The heat-conducting seat 224 has a heat-conducting core inside, and the core and the induction heating element 223 are connected in an insert structure. An induction coil 227 is sleeved between the induction heating element 223 and the heat-conducting seat 224. Initially, neither the induction heating element 223 nor the heat-conducting seat 224 is within the loop of the induction coil 227. The terminals of the induction coil 227 are all extended through the induction heating element 227 after insulation. The lower mold 21 is exited and connected to an external electrical control device. The side of the heat conduction seat 224 near the stamping die groove 213 is fixed with a special-shaped heat conduction frame 225. The heat conduction frame 225 consists of an isolation sleeve and a heat conduction core material fixed inside the isolation sleeve. The isolation sleeve is fixed inside the lower mold 21. One end of the heat conduction core material is connected to the core inside the heat conduction seat 224. The surface of the heat conduction frame 225 facing the stamping die groove 213 is integrally provided with multiple upward-extending supports for heat conduction. The extended ends of the supports extend into the flat groove opened along the path at the groove opening of the stamping die groove 213 and make contact with the contact heat plate 226 fixed in the flat groove for heat conduction.

[0023] During operation, the metal plate is first placed in the stamping groove 213 on the upper surface of the lower mold 21. The hydraulic equipment is then activated to push the upper mold structure 1 closer to the lower mold structure 2. The stamping plate 12 in the upper mold structure 1 moves downward with the assembly template 11. The lower end of the positioning piston rod 1222's ball contacts the metal plate and slides upward under the reaction force, stretching the spring. At the same time, it compresses the release agent and spraying material in the transfer liquid chamber 1221. The release agent enters the hydraulic chamber 212, pressing the piston lifting plate 22 downward, simultaneously stretching the hydraulic spring 221 and the telescopic rod 222, and causing the induction heating element 223 to enter the range of the induction coil 227 and be heated. Heat is conducted to the contact heat plate 226 and the heat conduction cavity 2131 to preheat the metal plate and the stamping die 213. The coating material is sprayed onto the surface of the metal plate. When the release agent breaks through the pressure limit of the one-way valve of the injection pipeline 2122, it enters the stamping die 213 for lubrication. After the stamping plate 12 moves down and attaches to the surface of the lower mold 21, the piston lifting plate 22 is reset, stopping heating and heat conduction. At this time, the positioning piston rod 1222 is fully retracted, and the hydraulic equipment continues to push the assembly template 11 down, compressing the buffer spring 111 and pushing the stamping part 112 to stamp the metal plate. The release agent diffuses, and the coating material forms a heat insulation protective layer.

[0024] In summary, through the assembly template 11, buffer spring 111, stamped part 112, stamping plate 12, material replenishment box 121, limiting column 122, transfer liquid chamber 1221, positioning piston rod 1222, lower mold 21, assembly part 211, hydraulic chamber 212, liquid inlet pipe 2121, liquid injection pipe 2122, stamping die groove 213, piston lifting plate 22, hydraulic spring 221, telescopic rod 222, induction heating element 223, heat conducting seat 224, isolation heat conducting frame 225, contact heat plate 226, and induction coil 227, During the stamping process, the pressure of the stamping can be used to force the release agent inside the limiting column 122 into the hydraulic chamber 212, causing the piston lifting plate 22 inside the hydraulic chamber 212 to move along the inner wall of the hydraulic chamber 212. During the downward movement, it works with the induction coil 227 to heat the induction heating element 223, and conducts the heat inside the induction heating element 223 to the heat conduction seat 224, the heat isolation frame 225, and the contact heat plate 226. This can heat the metal plate and the stamping die 213. At the same time, the release agent can enter during stamping. Inside the stamping die groove 213, a lubricating film is formed at the contact interface between the metal sheet and the stamping die groove 213. According to the above design, the metal sheet can be heated during the stamping process, significantly improving its plasticity and reducing the internal stress generated during stamping due to excessive material rigidity. Especially in the forming process of some complex shapes, such as the bending parts and edge areas of the heat shield, local heating allows the metal sheet to better adapt to the changes in the shape of the die, further reducing the possibility of stress concentration and cracking, and improving the quality stability of the product. Moreover, the use of the mold release agent greatly reduces the friction between the metal sheet and the die. During the stamping process, the reduction of friction significantly reduces the tensile stress borne by the metal sheet. When the metal sheet undergoes plastic deformation in the die, especially in areas prone to stress concentration such as corners, sharp corners, or small radius areas, the additional tensile stress caused by friction is reduced, thereby effectively avoiding cracking caused by excessive stress. Furthermore, the lubricating effect of the mold release agent makes the deformation of the metal sheet in the die smoother, improving the forming quality and the product qualification rate.

[0025] As one embodiment of the present invention, such as Figures 1 to 6 As shown, the sides of the limiting posts 122 located at the front and rear sides of the replenishment box 121 are respectively provided with input and output one-way interfaces. The output one-way interface is fixedly connected to the spraying component 1223 for spraying material onto the surface of the metal plate, and the input one-way interface is connected to the paint supply equipment.

[0026] The heat-conducting isolation frame 225 has multiple upward-extending supports for heat conduction integrally provided on the surface facing the stamping die groove 213. The extended ends of the supports extend into the interior of the heat-conducting cavity 2131 and contact the heat-conducting material provided inside the heat-conducting cavity 2131 for heat conduction. The heat-conducting cavity 2131 is spaced apart and located directly below the stamping die groove 213 inside the lower mold 21. The heat-conducting cavity 2131 is arranged to partially enclose the tube diameter of the stamping die groove 213.

[0027] During operation, the positioning piston rod 1222 slides upward under the reaction force to stretch the spring, while compressing the spraying material in the transfer liquid chamber 1221. The spraying material is sprayed onto the surface of the metal plate through the spraying component 1223 and forms a heat insulation protective layer on the surface of the metal plate under the action of heating.

[0028] In summary, by configuring the stamping plate 12, limiting column 122, transfer liquid chamber 1221, positioning piston rod 1222, spraying part 1223, lower mold 21, assembly 211, hydraulic chamber 212, liquid inlet pipe 2121, liquid injection pipe 2122, stamping die groove 213, heat conduction cavity 2131, piston lifting plate 22, hydraulic spring 221, telescopic rod 222, induction heating element 223, heat conduction seat 224, isolation heat conduction frame 225, and induction coil 227, specific materials can be sprayed onto the surface of the metal plate during the stamping process. These materials form a heat insulation layer on the surface of the metal plate during the subsequent heating process, eliminating the need for additional heat insulation treatment after stamping in traditional processes. This innovative design greatly shortens the production cycle and improves production efficiency. In actual production, there is no need to transfer the stamped parts to other equipment or processes for heat insulation treatment, reducing time waste and operational complexity in intermediate links. At the same time, the simultaneous spraying and stamping can better ensure the bonding strength and uniformity between the heat insulation layer and the metal plate, improving the overall performance and quality of the product.

[0029] Working Principle: First, the upper mold structure 1 is bolted to the output end of the hydraulic equipment, ensuring a secure installation so that it can accurately receive power from the hydraulic equipment and perform corresponding actions. The lower mold structure 2 is bolted to the designated mounting base, ensuring that the upper mold structure 1 and lower mold structure 2 are accurately aligned and positioned directly below each other, preparing for subsequent stamping operations. Simultaneously, check the sufficiency of the release agent in the replenishment tank 121, and the sealing of the connections to the replenishment tank 121 and components such as the limiting post 122. Inspect the hydraulic chamber 212, injection pipe 2122, and inlet pipe 2121 in the lower mold structure 2 to ensure unobstructed flow and no leaks, and that the check valve functions properly. Also check the sensing wire. Check whether the connection between ring 227 and external electrical control equipment is normal, and the installation stability of components such as induction heating element 223 and heat conduction seat 224. After the inspection is completed, it can be used. During use, first cut the metal plate (mostly aluminum plate or honeycomb aluminum plate) to the specified size, then place the metal plate on the upper surface of the lower mold 21, so that the metal plate is stably placed in the position of the stamping die groove 213. Then start the hydraulic equipment to push the upper mold structure 1 downward, so that the upper mold structure 1 moves closer to the lower mold structure 2. At this time, the stamping plate 12 in the upper mold structure 1 moves downward together with the assembly template 11. The ball at the lower end of the positioning piston rod 1222 will first contact the metal plate. As the upper mold structure 1 continues to move downward, the positioning piston rod 1222 is subjected to the reaction force of the metal plate. The force will slide upward along the transfer liquid chamber 1221 to stretch the spring, which plays a certain role in buffering and positioning, ensuring the accuracy of the stamping position. The rolling design of the ball can reduce the friction with the surface of the metal plate, avoiding damage to the surface of the metal plate before and during stamping. At the same time, during the sliding process, the positioning piston rod 1222 will compress the mold release agent and spraying material in the transfer liquid chamber 1221, so that the mold release agent and spraying material enter the corresponding pipeline. Among them, the mold release agent will enter the interior of the hydraulic chamber 212 along the pipeline and hydraulically force the piston lifting plate 22 to slide downward along the inner wall of the hydraulic chamber 212. During the downward movement of the piston lifting plate 22, the synchronous stretching hydraulic spring 221 and telescopic rod 222 are stretched, and the induction heating element 22 is pushed. 3. Gradually entering the range of induction coil 227, the energized induction coil 227 can adjust the magnetic field strength and heating temperature according to actual needs to generate eddy currents inside the induction heating element 223 by alternating magnetic fields. This causes the electrons inside the induction heating element 223 to move at high speed and randomly, generating heat and thus heating the induction heating element 223. The heated induction heating element 223 will continue to move down and insert into the heat-conducting base 224. Then, the heat from the induction heating element 223 will be conducted to the interior of the heat-conducting base 224 and extend to the heat-conducting core of the heat-conducting base 224 and the heat-conducting frame 225, conducting heat to the contact heat plate 226 and the heat-conducting cavity 2131, heating the contact heat plate 226 and the heat-conducting cavity 2131. Among them, the contact heat plate 226 will conduct heat to the surface of the metal plate.The heat-conducting material inside the heat-conducting cavity 2131 absorbs and radiates heat to the stamping die groove 213, preheating the stamping die groove 213. Meanwhile, the coating material is evenly sprayed onto the metal plate surface through the spraying part 1223 along the pipeline. As the stamping plate 12 continues to descend and before adhering to the surface of the lower mold 21, the release agent continuously enters the hydraulic chamber 212, exceeding the opening pressure limit of the one-way valve relief valve inside the injection pipeline 2122. The release agent inside the hydraulic chamber 212 then exits through the one-way valve into the stamping die groove 213, lubricating its interior. As the release agent leaks out of the hydraulic chamber 212, the hydraulic force of the piston lifting plate 22 gradually decreases and approaches the initial hydraulic pressure. During this process, the metal plate remains heated. This localized heating improves the plasticity of the metal plate, further reducing stress concentration during stamping and preventing cracking. The material sprayed on the surface of the metal plate is in a micro-cured state, while the stamping die 213 is also preheated. When the stamping plate 12 moves down and adheres to the surface of the lower die 21, the piston lifting plate 22 returns to its initial position with the assistance of the hydraulic spring 221. Then, the induction heating element 223 moves out of the effective range of the induction coil 227, stopping the heating of the induction heating element 223 and the heat conduction of the induction heating element 223 to the heat conduction seat 224, the isolation heat conduction frame 225, the contact heat plate 226, and the heat conduction cavity 2131. At this time, the positioning piston rod 1222 fully retracts into the transfer liquid chamber 122. Inside 1, the hydraulic equipment continues to push the assembly template 11 downwards, which then compresses the buffer spring 111. Simultaneously, the compression of the buffer spring 111 stably pushes the stamped part 112 towards the metal plate, initiating the stamping process. This causes the metal plate to gradually deform and enter the stamping die groove 213 of the lower die structure 2. During the stamping process, under the influence of the extrusion pressure, the release agent evenly diffuses between the stamping die groove 213 and the stamped heat insulation cover. Meanwhile, the sprayed material forms a dense heat insulation protective layer on the surface of the metal plate under the continuous residual heat. After stamping is completed (after the heat insulation protective layer and heat insulation cover have stabilized), the hydraulic equipment drives the upper die structure 1 upwards. At this time, the stamping plate 12 and the stamped part 112 move upwards along with the assembly... Template 11 rises together, and positioning piston rod 1222 returns to its original position under the action of a spring in transfer chamber 1221. The return of positioning piston rod 1222 directly causes a change in the volume of transfer chamber 1221 below it, specifically an increase in volume after compression and reset. This means that if the volume of a closed system increases without new gas or liquid being added, the pressure within the system will decrease, creating a negative pressure environment below atmospheric pressure. This negative pressure environment further triggers the opening mechanism of the one-way valve between limiting column 122 and replenishment box 121, opening it to limiting column 122. The release agent then enters the interior of limiting column 122, thus replenishing the release agent inside the limiting column 122.After the upper mold structure 1 and the lower mold structure 2 have completely separated, the heat insulation cover can be demolded. After demolding, the inside of the stamping die groove 213 needs to be cleaned to ensure its cleanliness before proceeding with the stamping operation of the next metal sheet.

[0030] It should be noted that the release agent should be a high-temperature resistant release agent, such as silicone oil release agent, fluorinated release agent, siloxane release agent, etc., and the best product can be selected according to the actual situation; the side of the replenishment box 121 has an interface for replenishing the release agent; the heat-conducting material inside the heat-conducting cavity 2131 can be any suitable solid, liquid, etc.; the spraying material inside the limiting column 122 can be a liquid or solution material that easily forms a heat insulation layer on the surface of the metal plate or aluminum plate after heating, such as ceramic precursor solution, organosilicon resin solution, etc., and the specific selection can be made according to the actual situation.

[0031] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A mold for forming and processing a heat shield for an automotive exhaust system to prevent cracking, comprising: The upper mold structure (1) has a structure for stamping metal plates and is installed at the output end of the hydraulic equipment by bolts; The lower mold structure (2) has a groove formed by stamping a metal sheet, which is bolted to a designated mounting base and is located directly below the upper mold structure (1). Its features are: The upper mold structure (1) includes a stamping plate (12). A feeding box (121) is fixedly provided on the upper surface of the stamping plate (12). At least four limiting posts (122) are provided on the peripheral side of the feeding box (121) between buffer springs (111), and the limiting posts (122) are all fixed on the upper surface of the stamping plate (12). A transfer liquid chamber (1221) is opened inside each of the limiting posts (122), and the transfer liquid chamber (1221) is located inside the transfer liquid chamber (1221). The part is provided with a positioning piston rod (1222) by means of a spring sliding limit. The lower end of the positioning piston rod (1222) slides through the transfer liquid chamber (1221) to the outside of the stamping plate (12). The protruding end of the positioning piston rod (1222) is provided with a rolling ball. A part of the limiting post (122) is connected to the inside of the replenishment box (121), and the side of the other part of the limiting post (122) is provided with a spraying part (1223) for spraying material onto the surface of the metal plate. The lower mold structure (2) includes a lower mold (21). A stamping groove (213) is formed on the surface of the lower mold (21), and hydraulic chambers (212) are symmetrically formed on both sides of the stamping groove (213) inside the lower mold (21). Multiple injection pipes (2122) and inlet pipes (2121) are respectively formed on both sides above and near the stamping groove (213) inside the hydraulic chambers (212). The inlet pipes (...) 2121) is correspondingly set with the limiting column (122) and connected by a retractable pipe. The injection pipe (2122) is evenly distributed on both sides of the stamping die groove (213), and one end of the injection pipe (2122) extends into the stamping die groove (213). The injection pipe (2122) is equipped with a one-way valve inside. A piston lifting plate (22) is sealed and slidably set in the upper middle position inside the hydraulic chamber (212). The piston lifting plate (2121) is... 2) A hydraulic spring (221) and a telescopic rod (222) are movably fixed at the center of the upper surface. A plurality of induction heating elements (223) are fixedly installed on the lower surface of the piston lifting plate (22). A heat-conducting seat (224) is fixedly installed at the bottom of the hydraulic chamber (212) directly below the induction heating elements (223). An induction coil (227) is sleeved between the induction heating elements (223) and the heat-conducting seat (224). The heat-conducting seat (224) is close to One side of the stamping die groove (213) is fixed to an insulating heat-conducting frame (225). The insulating heat-conducting frame (225) is integrally provided with a heat-conducting support on the surface facing the stamping die groove (213). The extended ends of the support extend into the interior of the heat-conducting cavity (2131) and into the flat groove opened along the path at the groove position of the stamping die groove (213), and make contact with the heat-conducting material provided inside the heat-conducting cavity (2131) and the contact heat plate (226) fixed in the flat groove for heat conduction.

2. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: The upper mold structure (1) also includes an assembly template (11). The assembly template (11) has flanges integrally provided at the center of both the upper and lower surfaces for connection. The flanges are connected and fixed to the hydraulic equipment and the stamping part (112) respectively. The lower surface of the stamping part (112) is integrally provided with a preset stamping model. The assembly template (11) has two rows of smooth lifting holes equidistantly opened on both sides of the flange. A buffer spring (111) is provided at the lower end of each lifting hole. The buffer spring (111) consists of a spring and a limiting slide. The assembly consists of a spring that is movably disposed between the assembly template (11) and the stamping plate (12), and a sliding rod that is inserted at the center of the spring. The lower end of the sliding rod is fixed to the stamping plate (12), and the upper end is slidably inserted into the lifting hole of the assembly template (11). The upper end of the sliding rod that passes through the lifting hole is limited by a nut. The plate shape of the stamping plate (12) is the same as that of the assembly template (11). The center of both the stamping plate (12) and the feeding box (121) is provided with through holes for limiting the lifting and sliding of the stamped part (112).

3. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: The lower mold (21) is fixedly provided with an assembly (211) at the center of its bottom.

4. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: The telescopic rod (222) is located at the center of the hydraulic spring (221), and the upper ends of both the hydraulic spring (221) and the telescopic rod (222) are fixed above the inside of the hydraulic chamber (212).

5. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: The heat-conducting base (224) is provided with a heat-conducting core inside, and the core and the induction heat element (223) are arranged in an interlocking structure.

6. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: Initially, the induction heating element (223) and the heat-conducting base (224) are not within the ring range of the induction coil (227). The power-connecting terminals of the induction coil (227) extend out of the lower mold (21) after insulation and isolation, and are connected to the external electrical control equipment.

7. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: The heat-conducting isolation frame (225) consists of an isolation sleeve and a heat-conducting core material fixed inside the isolation sleeve. The isolation sleeve is fixed inside the lower mold (21), and one end of the heat-conducting core material is connected to the core inside the heat-conducting seat (224).

8. The anti-cracking forming mold for a heat shield of an automotive exhaust system according to claim 1, characterized in that: The heat conduction cavity (2131) is spaced apart and located directly below the stamping die groove (213) inside the lower mold (21), and the heat conduction cavity (2131) is arranged to surround the tube diameter of the stamping die groove (213) in a semi-enclosed manner.

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