Pressing ring cooling system of drawing die, design method and cold stamping production line

Abstract

The invention provides a material pressing ring cooling system of a drawing die, a design method and a cold stamping production line, and relates to the technical field of cold stamping in automobile manufacturing. Specifically, the material pressing ring cooling system used for the drawing die comprises a material pressing ring, a cooling device, a cooling device and a cooling device, wherein a working molded surface is formed on one side, close to the drawing die, of the material pressing ring; and the cooling pipe is embedded into the material pressing ring and extends in the circumferential direction of the material pressing ring, and a constant preset distance is formed between the center line in the length direction of the cooling pipe and the working molded surface. The problems that in the prior art, the cooling design of the material pressing ring is high in randomness, and the cooling effect is not stable are solved.

Description

Technical Field

[0001] This invention relates to the field of cold stamping technology in automobile manufacturing, and more specifically, to a cooling system for the blank holder ring of a drawing die, a design method, and a cold stamping production line. Background Technology

[0002] In existing technologies, the cooling design of the blank holder ring in cold stamping dies largely relies on experience, employing either external spray cooling or internal straight-hole cooling. While external spray cooling is simple to operate, it has low cooling efficiency and can easily interfere with the die's lubrication system, leading to uneven lubrication and affecting workpiece quality. Internal straight-hole cooling is limited by the machining process; the cooling channel's direction is difficult to conform to the complex three-dimensional working surface of the blank holder, and the cooling medium cannot directly contact or approach the core area where frictional heat generation occurs, resulting in poor cooling performance, especially in high-load areas such as around the drawbead groove, where an excessively long cooling path significantly reduces cooling efficiency.

[0003] No effective solution has yet been proposed to address the above issues. Summary of the Invention

[0004] The main objective of this invention is to provide a cooling system, design method, and cold stamping production line for the blank holder ring of a drawing die, in order to solve the problems of arbitrary design and unstable cooling effect of the blank holder ring in the prior art.

[0005] To achieve the above objectives, according to one aspect of the present invention, a pressure ring cooling system for a drawing die is provided, comprising: a pressure ring, wherein a working surface is formed on the side of the pressure ring near the drawing die; and a cooling pipe embedded inside the pressure ring, the cooling pipe extending circumferentially along the pressure ring, wherein a constant preset distance is maintained between the centerline of the cooling pipe in the length direction and the working surface.

[0006] Furthermore, the cooling pipe and the pressure ring are constructed using solid foam casting.

[0007] Furthermore, mounting blocks are provided at both the inlet and outlet of the cooling pipe. The mounting blocks are connected to the pressure ring by bolts. An air inlet connector is provided on the side of the mounting block located at the inlet of the cooling pipe away from the cooling pipe, and a muffler is provided on the side of the mounting block located at the outlet of the cooling pipe away from the cooling pipe.

[0008] Furthermore, the inlet of the cooling pipe is connected to the press through an air intake pipe, and a connecting device is provided at the end of the air intake pipe near the press. The air intake pipe is connected to the press through the connecting device.

[0009] Furthermore, the mounting block has internal flow channels, the diameter of which corresponds to the diameter of the cooling pipe.

[0010] Furthermore, the cooling system also includes a cooling device, which is located on the intake pipe and connected to the intake pipe.

[0011] According to another aspect of the present invention, a design method for a pressure ring cooling system for a drawing die is provided. The design method is used to process the aforementioned cooling system. The design method includes: generating a casting model of the pressure ring based on drawing process parameters and structural parameters of the pressure ring, wherein the drawing process parameters include sheet material, thickness, and stamping speed, and the casting model is made of foam material; obtaining the high heat load region of the pressure ring, the high heat load region being the area on the pressure ring that contacts the sheet material and experiences severe friction, the high heat load region typically concentrated around the drawing bead groove and at the rounded corners of the profile; planning the extension path of the cooling pipe based on the high heat load region, generating a target cooling pipe that satisfies the extension path; obtaining a blank die using a foam casting process, and processing the blank die to obtain the pressure ring cooling system.

[0012] Furthermore, based on the information of the high heat load area, the planning of the extension path of the cooling pipe includes: obtaining the height information of the centerline of the cooling pipe in the length direction and the height information of the working surface of the pressure ring; and generating the extension path of the cooling pipe while ensuring that the height difference between the height information of the centerline of the cooling pipe in the length direction and the height information of the working surface of the pressure ring remains constant.

[0013] Furthermore, a foam casting process is used to obtain a blank mold, including: pre-embedding the target cooling pipe inside the casting model according to the extension path; and using a molten metal casting model to integrally form the target cooling pipe and the pressure ring to obtain the blank mold.

[0014] According to one aspect of the present invention, a cold stamping production line is provided, which is configured to perform the above-described design method to process and form a pressure ring cooling system.

[0015] By applying the technical solution of this invention, a constant distance between the cooling pipe and the working surface is maintained through a closely conformal design, ensuring uniform cooling effect and creating conditions for increasing stamping speed, directly improving production efficiency. Simultaneously, it stabilizes the thermal state of the mold, avoiding mold damage caused by localized overheating. This application solves the problems of arbitrary design and unstable cooling effect of the pressure ring in the prior art. Attached Figure Description

[0016] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:

[0017] Figure 1A schematic diagram of a first embodiment of the pressure ring cooling system according to the present invention is shown;

[0018] Figure 2 A schematic diagram of a second embodiment of the pressure ring according to the present invention is shown;

[0019] Figure 3 A schematic diagram showing the position of an embodiment of the cooling pipe according to the present invention is provided;

[0020] Figure 4 A schematic diagram of an embodiment of the connecting device according to the present invention is shown;

[0021] Figure 5 A schematic diagram of an embodiment of the mounting block according to the present invention is shown;

[0022] Figure 6 A schematic flowchart illustrating an embodiment of the design method for a pressure ring cooling system of a drawing die according to the present invention is shown.

[0023] The above figures include the following reference numerals:

[0024] 100. Pressure ring;

[0025] 200. Cooling pipe;

[0026] 300. Air intake connector;

[0027] 400. Muffler;

[0028] 500, Installation Block;

[0029] 600. Cooling device;

[0030] 700. Intake pipe;

[0031] 800. Connecting device. Detailed Implementation

[0032] It should be noted that, unless otherwise specified, the embodiments and features described in this application can be combined with each other. The present invention will now be described in detail with reference to the accompanying drawings and embodiments.

[0033] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0034] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such terms can be used interchangeably where appropriate so that the embodiments of this application described herein can be implemented, for example, in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0035] Exemplary embodiments according to this application will now be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided so that the disclosure of this application is thorough and complete, and that the concept of these exemplary embodiments is fully conveyed to those skilled in the art. In the drawings, for clarity, the thickness of layers and regions may be exaggerated, and the same reference numerals are used to denote the same devices, and therefore their description will be omitted.

[0036] Combination Figures 1 to 5 As shown in the specific embodiment of this application, a cooling system for the pressure ring of a drawing die is provided.

[0037] Specifically, such as Figure 1 , Figure 2 As shown, a pressure ring cooling system for a drawing die includes: a pressure ring 100, the side of the pressure ring 100 near the drawing die forming a working surface; and a cooling pipe 200, which is embedded inside the pressure ring 100 and extends circumferentially along the pressure ring 100. The centerline of the cooling pipe 200 in the length direction has a constant preset distance from the working surface.

[0038] In this embodiment, as Figure 3As shown, the cooling pipe extends circumferentially along the pressure ring, maintaining a constant preset distance between its centerline along its length and the working surface. This design ensures that the cooling pipe closely follows the undulations of the working surface of the pressure ring, forming a so-called "conformal cooling" structure. During cold stamping, the constant distance between the cooling pipe and the working surface allows the cooling medium to act directly on the vicinity of the heat source generated by the friction between the pressure ring and the sheet metal, effectively improving cooling efficiency while avoiding the problem of cooling effect attenuation caused by excessively long cooling paths. This "near-source cooling" method improves the temperature distribution on the working surface of the pressure ring, reducing workpiece quality defects caused by localized overheating, such as wrinkling, cracking, and surface burning, thereby improving product qualification rate and consistency.

[0039] By applying the technical solution of this invention, the cooling pipe 200 is designed to closely conform to the working surface, maintaining a constant distance between the cooling pipe 200 and the working surface. This ensures uniform cooling effect, creating conditions for increasing stamping speed and directly improving production efficiency. Simultaneously, it stabilizes the thermal state of the mold, preventing mold damage caused by localized overheating. This application solves the problems of arbitrary design and unstable cooling effect of the pressure ring in the prior art.

[0040] Specifically, the cooling pipe 200 and the pressure ring 100 are formed using foam solid casting. This design fully utilizes the process characteristics of foam solid casting, allowing the cooling pipe 200 to be pre-embedded on the complex three-dimensional surface of the pressure ring 100. By precisely placing the cooling pipe 200 inside the foam model and solidifying it together with the body material of the pressure ring 100 during the subsequent casting process, a gapless and tight fit between the cooling pipe 200 and the pressure ring 100 is ensured, thereby greatly improving heat transfer efficiency. The one-piece molded cooling pipe 200 can accurately follow the undulations of the working surface of the pressure ring 100, forming an efficient and uniform "conformal cooling" effect, effectively reducing the temperature in high-friction areas and improving the thermal balance of the mold. This design not only improves the efficiency and reliability of the cooling system but also simplifies the mold assembly process, avoids common leakage and maintenance problems in traditional cooling systems, and thus improves the stability and efficiency of the entire production line.

[0041] Specifically, mounting blocks 500 are provided at both the inlet and outlet of the cooling pipe 200. The mounting blocks 500 are connected to the pressure ring 100 by bolts. An air inlet connector 300 is provided on the side of the mounting block 500 at the inlet of the cooling pipe 200 away from the cooling pipe 200, and a silencer 400 is provided on the side of the mounting block 500 at the outlet of the cooling pipe 200 away from the cooling pipe 200. This layout not only simplifies the assembly process of the cooling system, but also ensures that the cooling medium smoothly enters the cooling pipe 200 from the air inlet connector 300 and is smoothly discharged through the silencer 400 after heat exchange, minimizing noise pollution.

[0042] Optionally, the mounting block 500 acts as a bridge between the cooling pipe 200 and the external cooling device. By placing mounting blocks at the inlet and outlet of the cooling pipe 200, the mounting block 500 provides standardized connection interfaces, facilitating the matching of various sizes of air intake connectors 300 and mufflers 400. This design not only simplifies the installation and maintenance process but also promotes the system's versatility and replaceability. It achieves a seamless connection between the cooling pipe and the external system, ensuring a smooth and leak-free inflow and outflow of the cooling medium.

[0043] To prevent coolant leakage, the connection between the mounting block 500 and the cooling pipe 200 must be sealed with a sealing ring or high-temperature resistant sealant. This not only ensures leak-free transmission of the coolant but also guarantees stable operation of the cooling system even in high-temperature environments.

[0044] Specifically, such as Figure 4 As shown, the inlet of the cooling pipe 200 is connected to the press via the air intake pipe 700. A connecting device 800 is provided at the end of the air intake pipe 700 closest to the press, ensuring a secure and sealed connection between the air intake pipe 700 and the press. This design allows the cooling system to automatically receive the cooling medium supplied from the press, thus achieving automated integration of the cooling function. Through the precise connection of the connecting device 800, the cooling medium is smoothly transferred from the press to the cooling pipe 200, effectively removing the heat generated by the pressure ring during operation and maintaining its thermal stability during the stamping process.

[0045] The intake pipe 700 acts as a bridge connecting the inlet of the cooling pipe 200 to the stamping machine. It is responsible for transporting the processed cooling medium, such as compressed air, into the cooling pipe to achieve the cooling process. The intake pipe 700 must have good pressure resistance and thermal stability to adapt to the high-temperature and high-pressure environment during the stamping production process.

[0046] The connecting device 800 is located at the end of the air inlet pipe 700 near the press. The connecting device 800 is typically a quick-connect self-sealing connector or other form of sealing interface, used to tightly connect with the air source outlet of the press. The design of the connecting device 800 must ensure both quick connection and sealing, so as to achieve instant connection and disconnection during production, while preventing leakage of the cooling medium during transmission, ensuring cooling effect and production safety.

[0047] The connecting device 800 ensures leak-free transmission of the cooling medium through a tight seal with the air source outlet of the press, avoiding reduced cooling effect or safety issues in the production environment caused by medium leakage. Meanwhile, the pressure resistance of the air inlet pipe 700 ensures stable transmission of the cooling medium under high pressure, maintaining the normal operation of the cooling system even under high-speed operation of the press.

[0048] Specifically, such as Figure 5 As shown, the mounting block 500 has a flow channel inside, and the diameter of the flow channel corresponds to the diameter of the cooling pipe 200. The purpose of keeping the diameter of the flow channel consistent with the diameter of the cooling pipe 200 is to ensure that the flow rate and pressure of the cooling medium remain stable throughout the system, and to avoid a decrease in cooling effect due to increased flow resistance.

[0049] Optionally, the cooling device, the air intake pipe and the air source connection device of the press together constitute an external cooling circuit to provide the system with the processed cooling medium.

[0050] In this embodiment, the cooling pipe 200 is made of metal material, and the cross-sectional shape of the cooling pipe 200 is circular or elliptical.

[0051] In other embodiments not shown, the internal flow channels of the mounting block 500 can also be adapted and adjusted according to the different diameters or shapes of the cooling pipes 200 to meet the diverse requirements of different mold structures and cooling needs.

[0052] Specifically, the cooling system also includes a cooling device 600, which is installed on the air inlet pipe 700 and connected to it. The function of the cooling device 600 is to pre-treat the compressed air from the press air source, including filtering impurities, reducing humidity, and lowering temperature to ensure the purity and low temperature of the cooling medium. By installing the cooling device on the air inlet pipe, the cooling system can continuously supply treated compressed air to the cooling pipes within the pressure ring, effectively absorbing the heat generated by the mold during the stamping process, maintaining the mold's operating temperature within an ideal range, thereby improving production efficiency and product quality.

[0053] The cooling unit 600 is the heart of the entire cooling system. Its main responsibility is to filter, dry, and cool the compressed air from the factory air source, ensuring the cooling medium is in optimal condition before entering the cooling pipe 200. The cooling unit 600 includes, but is not limited to: a filter: used to remove oil, dust, and other impurities from the compressed air, maintaining the purity of the cooling medium and preventing blockage of the cooling pipe or contamination of the pressure ring and workpiece; a dryer: removing moisture from the cooling medium to prevent condensation during cooling, which could affect the cooling effect or damage the mold; and a cooler: using refrigerant or water cooling to lower the temperature of the compressed air to a suitable cooling temperature, thereby improving cooling capacity.

[0054] According to another aspect of the invention, such as Figure 6 As shown, a design method for a cooling system of the blank holder ring of a drawing die is provided. The design method is used to process the aforementioned cooling system and includes:

[0055] Step S102: Based on the drawing process parameters and the structural parameters of the pressure ring, generate a casting model of the pressure ring. The drawing process parameters include the sheet material, thickness, and stamping speed. The casting model is made of foam material.

[0056] Sheet material: refers to the type of metal sheet used for cold stamping, such as steel, aluminum, alloy steel, etc. Different materials will affect the thermal conductivity, deformation characteristics, and wear resistance of the sheet during the drawing process, and will impose different requirements on the design of the cooling system.

[0057] Sheet thickness: This determines the stress and heat load on the sheet during the drawing process. Thicker sheets generate more heat during drawing due to greater friction, requiring a cooling system with stronger heat exchange capacity and a more rational cooling pipe layout.

[0058] Stamping speed: This refers to the operating speed of the die during the drawing process. Higher stamping speeds result in a greater conversion of kinetic energy into heat energy, increasing the thermal load on the blank holder and requiring a cooling system with faster response and higher cooling efficiency.

[0059] These process parameters not only affect the efficiency of the drawing process and the quality of the workpiece, but also directly determine the heat distribution and heat load of the pressure ring under working conditions. Therefore, the model generated based on the drawing process parameters can ensure that the model design fully considers the thermal management needs in actual production, providing accurate data support for the subsequent design of the cooling system.

[0060] The structural parameters of the pressure ring include its overall length, width, and height, as well as various key internal and external dimensions, such as the depth and width of the drawbead grooves and the radius of the fillet radius. These dimensions determine the physical space of the pressure ring and also affect the layout and orientation of the cooling pipes.

[0061] Based on the drawing process parameters (such as sheet material, thickness, and stamping speed) and the structural parameters of the pressure ring, a comprehensive analysis is conducted to design a three-dimensional digital model of the pressure ring. This model can reflect the heat load distribution of the pressure ring under real production conditions, guide the rational layout of cooling pipes, and ensure that the cooling medium can directly act on high heat load areas. A casting model of the pressure ring is made using foam material. The selection of the foam material must consider its stability and solubility during the high-temperature molten metal pouring process to ensure that the model can accurately disappear during the casting process without leaving any residue.

[0062] Step S104: Obtain the high heat load area of ​​the pressure ring. The high heat load area is the area on the pressure ring that comes into contact with the sheet metal and experiences severe friction. The high heat load area is usually concentrated around the draw bead groove and at the rounded corners of the profile.

[0063] By using numerical simulation, thermal analysis software, or based on production experience, identify the areas on the blank holder that come into contact with the sheet metal and experience intense friction—the high-heat-load areas. These areas are typically concentrated around the drawbead grooves and at the fillet corners of the profile, where the heat generated by friction is concentrated and requires focused cooling. Accurate identification of these high-heat-load areas ensures that the cooling system can be designed to target these heat sources, thus optimizing thermal energy management.

[0064] Step S106: Based on the high heat load area, plan the extension path of the cooling pipe and generate the target cooling pipe that meets the extension path.

[0065] In 3D design software, the 3D extension path of the cooling pipe is planned based on the location of high heat load areas. This design must ensure that the cooling pipe closely follows the complex working surface of the pressure ring, undulating in 3D space to achieve "near-source cooling." The planning of the extension path must take into account the flow characteristics of the cooling medium, ensuring that the inner diameter of the cooling pipe matches the flow rate of the cooling medium to provide optimal cooling effect. Based on the planned extension path, a target cooling pipe model that meets the design requirements is generated. The cooling pipe model must include specific dimensions, material, bending radius, and other parameters to ensure feasibility and efficiency in subsequent manufacturing processes.

[0066] Step S108: Using foam casting process, obtain blank mold, and process blank mold to obtain pressure ring cooling system.

[0067] Steps S102 to S108 generate a casting model based on the drawing process parameters and the pressure ring structure parameters, accurately identifying the high heat load area of ​​the pressure ring. This allows for the planning of the cooling pipe's extension path, and finally, the pre-embedding of the target cooling pipe is achieved using foam casting. This method not only ensures that the cooling pipe precisely conforms to the working surface of the pressure ring, forming a "conformal cooling" structure, improving cooling efficiency and uniformity, but also achieves deep integration of the cooling structure and mold manufacturing process by considering cooling requirements in the early design stages. Compared to traditional straight-hole cooling methods, this design method overcomes the limitation of the cooling path being far from the core heat source, effectively improving the design flexibility and cooling efficiency of the cooling system.

[0068] Specifically, step S106, based on information about high heat load areas, plans the extension path of the cooling pipes, including:

[0069] Step S1061: Obtain the height information of the centerline of the cooling pipe along its length and the height information of the working surface of the pressure ring;

[0070] In 3D CAD software, by drawing or importing a digital model of the pressure ring 100, the height information of each point on the working surface of the pressure ring can be obtained. Simultaneously, the centerline of the cooling pipe 200 along its length is defined, and the height data of this centerline at various locations is recorded.

[0071] Step S1062: Under the condition that the height difference between the height information of the centerline of the cooling pipe in the length direction and the height information of the working surface of the pressure ring remains constant, the extension path of the cooling pipe is generated.

[0072] In one specific embodiment, firstly, the height information of the centerline of the cooling pipe 200 along its length and the height information of the working surface of the pressure ring 100 at corresponding points need to be collected. This data can be obtained through 3D scanning, CAD modeling, or other measurement methods. Then, based on the collected height information, the height difference between the centerline of the cooling pipe and the working surface of the pressure ring at any point is calculated. This height difference should remain constant to ensure a constant optimal distance between the cooling pipe and the working surface. Under the premise of ensuring a constant height difference, a 3D extension path of the cooling pipe is generated using 3D design software or algorithms. This path needs to ensure that the cooling pipe can cover all high heat load areas and minimize detours and repetitions to improve cooling efficiency. The generated path also needs to be optimized to eliminate any corners or narrow sections that may cause poor medium flow. Finally, the effectiveness of the path is verified through simulation analysis or physical experiments to ensure that the cooling medium can be evenly distributed to the required cooling parts, achieving a stable and efficient cooling effect.

[0073] The cooling pipe extension path, generated when the height difference between the centerline of the cooling pipe 200 and the working surface of the pressure ring 100 remains constant, ensures that during the die stamping process, regardless of changes in the working surface of the pressure ring 100, the cooling medium remains in close contact with the heat source, achieving precise heat conduction and rapid heat dissipation. This design effectively overcomes the problems of low cooling efficiency and unstable temperature control caused by excessive distance between the cooling pipe and the working surface in traditional cooling methods.

[0074] By acquiring precise height information and using a path planning method with a constant height difference, the present invention achieves a perfect match between the working surface of the cooling pipe and the pressure ring, ensuring that the cooling medium can directly act on the vicinity of the heat source, thereby improving cooling efficiency and uniformity.

[0075] Specifically, step S108 employs a foam casting process to obtain a blank mold, including:

[0076] Step S1081: Embed the target cooling pipe inside the casting model according to the extension path;

[0077] In the 3D design software, the 3D extension path of the cooling pipes has been planned based on the information of the high heat load area. This ensures that the cooling pipes closely follow the changes in the working surface of the pressure ring, achieving "conformal cooling." Inside the foam casting model of the pressure ring, the foam model of the cooling pipes is precisely placed along the planned 3D path. Fixtures or adhesives are used to fix their position, ensuring they do not move during subsequent casting processes and maintain consistency with the planned path.

[0078] Step S1082: Use a molten metal casting model to integrally form the target cooling pipe and the pressure ring, and obtain a blank mold.

[0079] The foam casting model with pre-embedded cooling pipe foam model is placed in the sand mold, and a sand mold shell is formed around the foam casting model by filling with sand mold material (such as quartz sand).

[0080] Inside the sand mold shell, the metal material is melted into a liquid state at high temperature, and then the molten metal is injected into the sand mold to cover the entire foam casting model, including the pre-embedded cooling pipe foam model.

[0081] After the molten metal is poured into the sand mold, it rapidly heats the foam casting model, causing the foam to quickly disappear and be released as gas. Simultaneously, the molten metal begins to cool and solidify, gradually forming the metal pressure ring. The pre-embedded cooling pipes are also encased in metal, achieving integrated molding of the cooling pipes and the pressure ring. After the metal has completely solidified and cooled, post-processing steps such as sand mold stripping and excess metal removal are performed to obtain the blank mold.

[0082] Through the steps described above, the foam solid casting process employed in this invention not only achieves integrated molding of the cooling pipe and the pressure ring, improving the manufacturing precision and reliability of the cooling system, but also reduces production costs. Compared to traditional machining methods, the foam solid casting process reduces a large number of post-processing steps, such as drilling and welding, significantly lowering manufacturing costs and shortening the production cycle.

[0083] Specifically, the machining of the blank mold to obtain the pressure ring cooling system includes: using a CNC machine tool to precision machine the outer surface of the pressure ring to meet the dimensional tolerances and surface roughness requirements specified in the design drawings. Ensuring the matching accuracy between the pre-embedded area of ​​the cooling pipe and the working surface of the pressure ring is crucial for the cooling effect. Next, the various mounting surfaces of the blank mold are precision machined, especially the mounting positions of the mounting blocks, ensuring flatness and perpendicularity to guarantee a good fit between the mounting blocks and the pressure ring, achieving a seal and a stable connection. The channels of the cooling pipes inside the pressure ring are cleaned using a high-pressure air gun or specialized cleaning tools to remove residues generated during the casting process, such as sand particles and oxide scale, ensuring unobstructed channels and smooth flow of the cooling medium. The mounting blocks are machined using a CNC machine tool, with pre-set flow channels inside for connecting the cooling pipes to the external cooling device. The mounting blocks are fixed to the pre-reserved mounting surface on the pressure ring with bolts, ensuring sealing and stability. Standard parts such as air inlet connectors and silencers that meet the requirements are procured according to the design specifications of the standardized integration phase. These standard parts need to have good pressure resistance and temperature resistance to adapt to the working conditions of the cooling system. The pressure ring cooling system is obtained by connecting the above standard parts with the blank mold.

[0084] According to one aspect of the present invention, a cold stamping production line is provided, which is configured to perform the above-described design method to process and form a pressure ring cooling system.

[0085] In one specific embodiment, the specific steps for forming the pressure ring cooling system by design method are as follows: A digital model of the pressure ring 100 is established in 3D CATIA software. Based on a comprehensive analysis of drawing process parameters such as sheet material, thickness, and stamping speed, the high heat load areas on the pressure ring that contact the sheet material and experience severe friction are located. These areas are typically concentrated around the draw bead grooves and at the rounded corners of the profile.

[0086] Subsequently, 3D wiring design of the cooling pipes 200 was carried out in these key areas. It was ensured that the centerline of the cooling pipes 200 always maintained a basically constant optimal distance from the working surface of the pressure ring 100, thereby forming a "conformal" path that closely follows the three-dimensional undulations of the surface, ensuring the maximization and uniformity of cooling efficiency.

[0087] The pre-embedding of the cooling tube 200 is achieved using a foam casting process. First, a foam mold is machined based on the CAD model of the pressure ring 100 using CNC equipment. Then, the pre-bent and verified metal cooling tube 200 is fixed inside the foam mold strictly according to the design path. Next, the traditional casting processes such as molding and pouring are completed. Finally, the molten metal solidifies in the cavity, forming a one-piece pressure ring casting that completely encloses the cooling tube 200.

[0088] The cast pressure ring blank is machined as necessary, and the inlet and outlet of the cooling pipe 200 are cleaned. Then, a non-standard, self-made mounting block 500 is installed at the inlet and outlet positions. This mounting block 500 is securely fixed to the body of the pressure ring 100 with bolts. The connection between the mounting block 500 and the end of the cooling pipe 200 can be secured with a sealing ring or a high-temperature sealant such as silicone sealant to ensure airtightness. The other end of the mounting block 500 is connected to the air inlet connector 300 or the muffler 400.

[0089] The pressure ring 100, with the air inlet connector 300 and silencer 400 installed, is mounted onto the mold. The air inlet connector 300 is connected to the output end of the cooling device 600 via the air inlet pipe 700 (such as a pressure-resistant hose). The cooling device 600 filters, dries, and cools the compressed air from the factory air source. Finally, the cooling device 600 is connected to the air source provided by the stamping press via a connection device 800, such as a quick-connect self-sealing connector, forming a complete, automatically operating cooling circuit.

[0090] During the production process, the treated cooling compressed air enters through the air inlet joint 300, flows through the conformal cooling pipe 200 embedded inside the pressure ring 100, and after fully absorbing heat, it becomes hot air and is discharged from the silencer 400, thereby achieving continuous and efficient cooling of the pressure ring.

[0091] As can be seen from the above description, the embodiments of the present invention achieve the following technical effects:

[0092] 1. Achieved scientific and standardized cooling system design: This invention elevates traditional "experience-based" cooling design into a replicable and verifiable systems engineering method. By establishing a complete design specification from requirements analysis and flow channel design to process implementation, it significantly improves the reliability and consistency of the design and shortens the development cycle.

[0093] 2. Improved cooling efficiency and uniformity: Through "pre-embedded" and "conformal" design, the cooling pipes are brought as close as possible to the core area of ​​frictional heat generation, forming a highly efficient "near-source cooling" channel. This structure allows the cooling medium to directly and uniformly remove heat from the main heat source, solving the inherent defects of traditional cooling methods such as long heat dissipation paths and uneven effects.

[0094] 3. Significantly Improved Product Quality and Production Efficiency: By precisely controlling the temperature of key areas of the blank holder, the temperature field in the sheet metal flow zone is effectively stabilized, fundamentally reducing quality defects such as wrinkling, cracking, and surface burning caused by localized overheating of the workpiece, thus significantly improving product qualification rate and consistency. Simultaneously, the stable thermal state of the die creates conditions for increasing stamping speed, thereby directly improving production efficiency.

[0095] 4. Extended mold life and reduced overall costs: Efficient thermal management significantly reduces the operating temperature and thermal cycling range of the pressure ring, effectively delaying thermal fatigue, thermal wear, and thermal deformation, thereby greatly extending the mold's service life. Furthermore, standardized design reduces the types of non-standard parts, lowering manufacturing and maintenance complexity and spare parts inventory costs.

[0096] 5. This invention creatively combines foam solid casting process with conformal cooling channel design, breaking through the limitations of traditional machining (drilling) on ​​the shape of cooling channels, making it possible to achieve ideal conformal cooling in a pressure ring with a complex three-dimensional surface, and has significant technological advancements.

[0097] For ease of description, spatial relative terms such as "above," "on top of," "on the upper surface of," "above," etc., are used herein to describe the spatial positional relationship of a device or feature as shown in the figures to other devices or features. It should be understood that spatial relative terms are intended to encompass different orientations in use or operation beyond the orientation of the device as described in the figures. For example, if the device in the figures were inverted, a device described as "above" or "on top of" other devices or structures would subsequently be positioned as "below" or "under" other devices or structures. Thus, the exemplary term "above" can include both "above" and "below." The device may also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatial relative descriptions used herein will be interpreted accordingly.

[0098] In addition to the above, it should be noted that the terms "one embodiment," "another embodiment," and "embodiment" used in this specification refer to specific features, structures, or characteristics described in connection with that embodiment, which are included in at least one embodiment described in the general description of this application. The appearance of the same expression in multiple places in the specification does not necessarily refer to the same embodiment. Furthermore, when a specific feature, structure, or characteristic is described in connection with any embodiment, the intention is to suggest that implementing such a feature, structure, or characteristic in conjunction with other embodiments also falls within the scope of this invention.

[0099] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions in other embodiments.

[0100] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A cooling system for the blank holder ring of a drawing die, characterized in that, include: A pressure ring (100) is provided, wherein the side of the pressure ring (100) near the drawing die forms a working surface; Cooling pipe (200) is embedded inside the pressure ring (100). The cooling pipe (200) extends circumferentially along the pressure ring (100). The center line of the cooling pipe (200) in the length direction has a constant preset distance from the working surface.

2. The cooling system according to claim 1, characterized in that, The cooling pipe (200) and the pressure ring (100) are formed by solid foam casting.

3. The cooling system according to claim 2, characterized in that, The inlet and outlet of the cooling pipe (200) are provided with mounting blocks (500), and the mounting blocks (500) are connected to the pressure ring (100) by bolts. The mounting block (500) located at the inlet of the cooling pipe (200) is provided with an air inlet connector (300) on the side away from the cooling pipe (200), and the mounting block (500) located at the outlet of the cooling pipe (200) is provided with a muffler (400) on the side away from the cooling pipe (200).

4. The cooling system according to claim 2, characterized in that, The inlet of the cooling pipe (200) is connected to the press through the air intake pipe (700). The end of the air intake pipe (700) near the press is provided with a connecting device (800). The air intake pipe (700) is connected to the press through the connecting device (800).

5. The cooling system according to claim 3, characterized in that, The mounting block (500) has a flow channel inside, and the diameter of the flow channel is set to correspond to the diameter of the cooling pipe (200).

6. The cooling system according to claim 4, characterized in that, The cooling system also includes: A cooling device (600) is provided on the air intake pipe (700) and is connected to the air intake pipe (700).

7. A design method for a cooling system of the blank holder ring of a drawing die, characterized in that, The design method is used to manufacture the cooling system according to any one of claims 1 to 6, and the design method includes: Based on the drawing process parameters and the structural parameters of the pressure ring, a casting model of the pressure ring is generated. The drawing process parameters include the sheet material, thickness, and stamping speed. The casting model is made of foam material. The high heat load area of ​​the pressure ring is obtained. The high heat load area is the area on the pressure ring that comes into contact with the sheet metal and experiences severe friction. The high heat load area is usually concentrated around the draw bead groove and at the rounded corners of the profile. Based on the high heat load region, the extension path of the cooling pipe is planned, and a target cooling pipe that meets the extension path is generated; A foam casting process is used to obtain a blank mold, and the blank mold is then processed to obtain a pressure ring cooling system.

8. The design method according to claim 7, characterized in that, Based on the information about the high heat load area, the planned extension path of the cooling pipe includes: Obtain the height information of the centerline along the length of the cooling pipe and the height information of the working surface of the pressure ring; The extension path of the cooling pipe is generated when the height difference between the height information of the centerline in the length direction of the cooling pipe and the height information of the working surface of the pressure ring is kept constant.

9. The design method according to claim 7, characterized in that, The blank mold is obtained by using a foam casting process, including: The target cooling pipe is pre-embedded inside the casting model according to the extension path; The casting model is formed by pouring molten metal into it, so that the target cooling pipe and the pressure ring are integrally formed to obtain the blank mold.

10. A cold stamping production line, characterized in that, The cold stamping production line is configured to perform the design method as described in any one of claims 7 to 9 to process and form the pressure ring cooling system.

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