An automatic drawing die temperature control apparatus and method

Abstract

This application relates to an automatic temperature control device and method for drawing dies. Through the coordinated operation of a temperature monitor, cooling pipeline structure, cooling execution components, and a control component, the control component uses the real-time cavity temperature collected by the temperature monitor as feedback. After comparing this with a preset temperature threshold, it dynamically adjusts the medium supply opening of the cooling execution component, replacing the traditional crude temperature control methods of passive natural heat dissipation, fixed-flow cooling, or workshop environment cooling. This achieves real-time sensing and fully closed-loop automated control of the drawing die's working temperature, effectively preventing heat accumulation and thermal deformation in the die cavity due to continuous stamping friction. It solves the core pain points of traditional solutions, such as low temperature control accuracy and inability to adapt to the dynamic temperature control requirements of high-speed continuous stamping conditions. This fundamentally reduces forming defects such as dark cracks and splits in sheet metal during drawing, significantly improving the production yield of automotive body stamping parts and the stability of the production line cycle time.

Description

Technical Field

[0001] This application relates to the field of automotive mold manufacturing and stamping, specifically to an automatic temperature control device and method for drawing dies. Background Technology

[0002] The automotive mold manufacturing and stamping industry is developing towards high-speed, high-efficiency, and high-precision production. The production cycle time of automotive body stamping production lines is continuously increasing. As the core tooling for body stamping, the stability of the working temperature of the drawing die directly determines the quality and yield of the sheet metal stamping. In the drawing and stamping process of automotive body parts, high-speed friction between the sheet metal and the drawing die's pressure ring and die cavity is an inevitable phenomenon in the production process. The industry's demand for precise temperature control of the drawing die is increasingly urgent to avoid part forming defects caused by abnormal temperatures and to ensure continuous high-speed production.

[0003] In related technologies, traditional drawing dies mostly adopt the basic structural design of the casting body. Some processes are equipped with simple cooling methods, or air conditioners are installed in the press for environmental cooling. Some dies do not have specific temperature control measures and rely solely on the natural heat dissipation of the die itself through heat conduction.

[0004] However, traditional drawing die structures cannot automatically sense temperature changes on the cavity surface, nor can they achieve automated, closed-loop control of the die temperature. The die surface is prone to heat accumulation due to friction, which leads to a rise in die temperature and causes slight deformation. This results in a smaller gap between the blank holder and the die, obstructing the flow of sheet metal. Consequently, the drawn automotive body parts are prone to forming defects such as dark cracks and cracks. Summary of the Invention

[0005] This application provides an automatic temperature control device and method for drawing dies, which can solve the technical problems of low temperature control accuracy, high cooling energy consumption, and easy occurrence of batch part forming defects caused by passive natural cooling or fixed flow cooling in the traditional drawing die stamping process.

[0006] In a first aspect, embodiments of this application provide an automatic temperature control device for a drawing die, comprising: Temperature monitor, used to collect temperature signals from the surface of the drawing mold cavity; Cooling piping structure, which is used to be embedded in the cavity of the drawing mold; A cooling actuator, which is connected to the cooling piping structure and is used to provide cooling medium to be delivered into the cooling piping structure; A control component is connected to the temperature monitor and the cooling execution component, and is used to receive the temperature signal collected by the temperature monitor, output a control signal to the cooling execution component according to a preset temperature threshold, and regulate the supply opening of the cooling execution component.

[0007] In conjunction with the first aspect, in one embodiment, the cooling actuation component includes a pneumatic solenoid valve, a vortex cooling cylinder, and a compressed air source; The pneumatic solenoid valve is connected between the vortex cooling cylinder and the compressed air source, and is used to receive the control signal from the control component to realize on / off switching and opening degree adjustment. The vortex cooling cylinder is used to convert the compressed air from the compressed air source into a low-temperature cold airflow, which is then transported to the cooling pipeline structure as a cooling medium.

[0008] In conjunction with the first aspect, in one embodiment, the control component includes a temperature threshold setting module, a temperature display module, and a signal control module; The temperature threshold setting module is used to preset the temperature control threshold of the drawing model cavity, the temperature display module is used to visualize the temperature signal collected by the temperature monitor, and the signal control module is used to output the corresponding control signal to the cooling execution component according to the temperature signal.

[0009] In conjunction with the first aspect, in one embodiment, the cooling pipeline structure includes two parallel cooling pipes, which are embedded in the drawing mold cavity and distributed on opposite inner sidewalls of the drawing mold cavity. One port of the cooling pipe is connected to the cooling execution component, and the other port is an exhaust port.

[0010] In conjunction with the first aspect, in one embodiment, the temperature monitor includes an infrared temperature sensor for non-contact acquisition of temperature signals from the surface of the drawing mold cavity and for real-time transmission of the temperature signals to the control component.

[0011] Secondly, embodiments of this application provide a temperature control method based on an automatic temperature control device for drawing dies as described in some of the above embodiments, which includes the following steps: The real-time temperature signal collected by the temperature monitor is transmitted to the control component, which then compares the real-time temperature with the preset temperature control threshold. If the real-time temperature reaches or exceeds the preset upper temperature threshold, the control component calculates the target flow rate of the cooling medium required based on the total heat generated by the drawing die, and outputs the corresponding opening control signal to the cooling execution component based on the target flow rate. If the real-time temperature drops to or below the preset lower temperature threshold, the control component outputs a cut-off signal to the cooling execution component, which then shuts off the media delivery path.

[0012] In conjunction with the second aspect, in one embodiment, if the real-time temperature reaches a preset upper temperature threshold, the control component calculates the target flow rate of the required cooling medium based on the total heat generated by the drawing die, including: When the real-time temperature reaches or exceeds the preset upper temperature threshold, the control component retrieves the preset stable working temperature of the mold and the preset cooling time that are bound to the upper temperature threshold. The first part of the heat generated by the temperature difference of the mold is calculated based on the mass of the pressure ring, the specific heat capacity of the casting, the temperature difference between the initial ambient temperature of the mold and the preset stable working temperature of the mold. Based on the real-time collected pressure of the blank holder, the friction coefficient between the sheet and the die, the press stamping speed, and the preset cooling time, the second part of the heat generated by the friction between the sheet and the die during the sheet drawing process is calculated. Based on the first part of the heat and the second part of the heat, the total heat generated during the drawing die stamping process is obtained.

[0013] In conjunction with the second aspect, in one embodiment, if the real-time temperature reaches a preset upper temperature threshold, the control component calculates the target flow rate of the required cooling medium based on the total heat generated by the drawing die, including: The specific heat capacity and inlet temperature of the cooling gas are obtained, and the heat exchange temperature difference between the stable working temperature of the mold and the inlet temperature of the cooling gas is calculated by combining the preset stable working temperature of the mold with the upper limit threshold temperature. Based on the principle of thermal balance, the total heat that the cooling gas can absorb within the preset cooling time is determined to match the total heat generated by the cooling medium during the stamping process of the drawing die. Based on the above thermal balance matching relationship, combined with the specific heat capacity of the cooling gas, the heat exchange temperature difference, and the preset cooling time, the target delivery flow rate of the cooling gas is calculated.

[0014] In conjunction with the second aspect, in one embodiment, the method further includes the following steps: based on the total heat generated during the drawing die stamping process, combined with the heat transfer characteristics of the cooling medium and the preset cooling time, the total design length of the cooling pipeline structure is calculated and determined by the principle of thermal balance.

[0015] In conjunction with the second aspect, in one embodiment, the total design length of the cooling pipe structure is determined by calculating based on the total heat generated during the drawing die stamping process, combined with the heat transfer characteristics of the cooling medium and a preset cooling time, using the principle of heat balance. This includes: The heat transfer coefficient of the cooling gas to the mold cast iron material and the preset pipe diameter parameters of the cooling pipe are obtained. Combined with the preset stable working temperature of the mold and the inlet temperature of the cooling gas, which are bound to the upper limit threshold of the temperature, the heat exchange temperature difference between the stable working temperature of the mold and the inlet temperature of the cooling gas is calculated. Based on the principle of thermal balance, the total heat that the cooling pipe needs to remove within the preset cooling time is determined to match the total heat generated by the cooling medium during the stamping process of the drawing die. Based on the above heat balance matching relationship, combined with the convective heat transfer coefficient of the cooling gas, the heat transfer temperature difference and the preset cooling time, the total heat transfer area required for the cooling pipeline is calculated. The total design length of the cooling pipe structure is calculated based on the preset pipe diameter parameters and total heat transfer area of ​​the cooling pipe.

[0016] The beneficial effects of the technical solutions provided in this application include: Through the coordinated operation of temperature monitors, cooling pipe structures, cooling actuators, and control components, the control component uses the real-time cavity temperature collected by the temperature monitor as feedback. After comparing it with a preset temperature threshold, it dynamically adjusts the medium supply opening of the cooling actuator, replacing the traditional crude temperature control methods of passive natural heat dissipation, fixed flow cooling, or workshop environment cooling. This achieves real-time sensing and fully closed-loop automated control of the drawing die's working temperature, effectively preventing heat accumulation and thermal deformation in the die cavity due to continuous stamping friction. It solves the core pain points of traditional solutions, such as low temperature control accuracy and inability to adapt to the dynamic temperature control requirements of high-speed continuous stamping conditions. It reduces forming defects such as dark cracks and cracks in sheet metal drawing from the root, significantly improving the production yield of body stamping parts and the stability of the production line cycle. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a structural block diagram of the automatic temperature control device for drawing dies provided in an embodiment of this application; Figure 2 This is a schematic flowchart illustrating the temperature control method of the automatic temperature control equipment for drawing dies according to an embodiment of this application. Detailed Implementation

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

[0020] This application provides an automatic temperature control device and method for drawing dies, which can solve the technical problems of low temperature control accuracy, high cooling energy consumption, and easy occurrence of batch part forming defects caused by passive natural cooling or fixed flow cooling in the traditional drawing die stamping process.

[0021] Firstly, such as Figure 1 As shown in the figure, this application provides an automatic temperature control device for a drawing die, comprising: a temperature monitor for collecting temperature signals from the surface of the drawing die cavity; a cooling pipeline structure for embedding within the drawing die cavity; a cooling execution component connected to the cooling pipeline structure and used to supply cooling medium to the cooling pipeline structure; and a control component connected to the temperature monitor and the cooling execution component, used to receive the temperature signals collected by the temperature monitor, output control signals to the cooling execution component according to a preset temperature threshold, and regulate the supply opening of the cooling execution component.

[0022] In this embodiment, a fully automated temperature control architecture is constructed through the coordinated operation of a temperature monitor, cooling pipeline structure, cooling execution components, and control components. This architecture encompasses real-time temperature acquisition, closed-loop signal processing, dynamic cooling execution, and directional cold energy delivery. The control component uses the real-time cavity temperature collected by the temperature monitor as feedback and dynamically adjusts the medium supply opening of the cooling execution components after comparing it with a preset temperature threshold. This replaces the traditional, crude temperature control methods of passive natural heat dissipation, fixed-flow cooling, or workshop environment cooling. This achieves real-time sensing and fully closed-loop automated control of the drawing die's working temperature, effectively preventing heat accumulation and thermal deformation in the die cavity due to continuous stamping friction. It solves the core pain points of traditional solutions, such as low temperature control accuracy and inability to adapt to the dynamic temperature control requirements of high-speed continuous stamping conditions. This fundamentally reduces forming defects such as dark cracks and splits in sheet metal during drawing, significantly improving the production yield of automotive body stamping parts and the stability of the production line cycle time.

[0023] In conjunction with the first aspect, in one embodiment, the cooling actuator includes a pneumatic solenoid valve, a vortex cooling cylinder, and a compressed air source; the pneumatic solenoid valve is connected between the vortex cooling cylinder and the compressed air source, and is used to receive control signals from the control component to realize on / off switching and opening adjustment; the vortex cooling cylinder is used to convert the compressed air from the compressed air source into a low-temperature cold airflow as a cooling medium and deliver it to the cooling pipeline structure.

[0024] In this embodiment, compressed air is used as the clean cooling medium, and a pneumatic solenoid valve is used as the core actuator for flow control. This valve receives linear electrical signals from the control components, enabling stepless and precise adjustment of valve on / off states and opening degree, achieving real-time matching between the cooling medium flow rate and the control signal. Simultaneously, utilizing the vortex tube physical effect of the vortex cooling cylinder, the ambient temperature compressed air input from the compressed air source is converted into a low-temperature cold airflow on-site. This eliminates the need for additional complex peripherals such as refrigeration units and water-cooled circulation systems, allowing for the directional delivery of cooling capacity to the mold cavity through the cooling pipeline structure. On one hand, the dynamic adjustment of the pneumatic solenoid valve opening achieves precise matching between the cooling medium flow rate and the mold's heating conditions, solving the problems of high energy consumption and insufficient temperature control accuracy inherent in traditional fixed-flow cooling. On the other hand, the vortex cooling air-cooling architecture avoids the industry risk of water-cooled system media leakage contaminating the mold and stamped parts. It can also be directly adapted to the common compressed air conditions in stamping workshops, resulting in low equipment modification costs, convenient installation, and rapid deployment without significant modifications to the existing drawing die structure.

[0025] In conjunction with the first aspect, in one embodiment, the control component includes a temperature threshold setting module, a temperature display module, and a signal control module; the temperature threshold setting module is used to preset a temperature control threshold for the drawing model cavity, the temperature display module is used to visually display the temperature signal collected by the temperature monitor, and the signal control module is used to output a corresponding control signal to the cooling execution component according to the temperature signal.

[0026] In this embodiment, a temperature threshold setting module enables personalized preset of the mold temperature control range, matching the differentiated temperature control requirements of different sheet metal materials, different vehicle parts, and different stamping processes. The temperature display module provides a synchronous and visual presentation of the cavity temperature in real time, facilitating continuous monitoring of the mold's operating status by production personnel and enabling timely troubleshooting of abnormal conditions. The signal control module, based on the comparison between the real-time temperature signal and the preset threshold, outputs a corresponding linear control signal to the cooling execution component, achieving automated, unmanned pre-execution of the temperature control logic. This achieves flexible configuration and full-process visual management of the drawing die temperature control parameters, significantly improving the equipment's versatility and ease of operation, and adapting to the drawing production needs of a full range of vehicle body stamping parts. Simultaneously, the linearized signal output of the signal control module ensures the response speed and control accuracy of the cooling flow regulation, effectively avoiding large fluctuations in mold temperature caused by temperature control lag, further enhancing the stability of the closed-loop temperature control system.

[0027] In conjunction with the first aspect, in one embodiment, the cooling pipeline structure includes two parallel cooling pipes, which are embedded in the drawing mold cavity and distributed on opposite inner sidewalls of the drawing mold cavity; one end of each cooling pipe is connected to the cooling execution component, and the other end is an exhaust port.

[0028] In this embodiment, a dual-path parallel straight-through cooling pipe structure is adopted. The cooling pipes are pre-embedded in the inner sidewall of the drawing die cavity, allowing the cold airflow to be delivered directly close to the forming surface of the die. The cooling energy is directly applied to the core area of ​​frictional heat generation in the cavity through heat conduction from the cast iron body of the die, achieving directional and precise heat exchange. The pipes adopt a straight-through flow channel design with air inlet at one end and air outlet at the other, which ensures the continuous and stable flow of cold air in the pipes and avoids the heat exchange efficiency reduction caused by cold energy stagnation and excessive flow channel resistance. By using dual-path cooling pipes arranged according to the shape of the cavity, directional and precise cooling of the heat generation area of ​​the die cavity is achieved, significantly improving heat exchange efficiency and solving the problems of large cold energy loss and poor cooling targeting in traditional workshop cooling methods. At the same time, the straight-through flow channel design can effectively avoid dust and liquid accumulation and blockage in the pipes, adapting to the long-term stable operation requirements of continuous stamping production. The pre-embedded structure does not affect the normal die closing and stamping action of the drawing die and has strong compatibility with existing die structures.

[0029] In conjunction with the first aspect, in one embodiment, the temperature monitor includes an infrared temperature sensor for non-contact acquisition of temperature signals from the surface of the drawing mold cavity and for real-time transmission of the temperature signals to the control component.

[0030] In this embodiment, a non-contact infrared temperature sensor is used as the core component for temperature acquisition. Based on the principle of infrared thermal radiation detection, it can acquire dynamic temperature signals of the working surface of the mold cavity in real time at high frequency without direct contact with the mold cavity surface. This completely avoids mechanical impact damage to the temperature acquisition element caused by the mold closing and stamping action, ensuring the stability of acquisition under high temperature and high impact stamping conditions. It achieves non-contact, high real-time, and accurate acquisition of the temperature of the drawing mold cavity, providing accurate and reliable input data for the closed-loop temperature control system and ensuring temperature control accuracy from the source. At the same time, the non-contact installation method avoids damage to the monitoring element caused by mechanical impact and high-temperature aging during the stamping process, greatly improving the service life and operational reliability of the equipment, and perfectly adapting to the harsh working environment of high-speed continuous stamping.

[0031] In conjunction with the first aspect, in one embodiment, the automatic temperature control device for the drawing die further includes a power supply component. The power supply component provides stable operating power to the temperature monitor, cooling actuator, and control component. The power supply component includes a first power supply branch and a second power supply branch, both of which can be selectively activated. The first power supply branch is adapted to the power supply configuration of a press with a reserved power supply interface, while the second power supply branch is adapted to the power supply configuration of a press without a reserved power supply interface. The first power supply branch includes a Harding die heavy-duty connector assembly, which is an industrial heavy-duty connector assembly. Its input end is electrically connected to the reserved power supply interface of the press, and its output end is electrically connected to the power supply terminals of the temperature monitor, cooling actuator, and control component, respectively, to connect the operating current of the press power supply circuit to the power supply system of the automatic temperature control device for the drawing die. The second power supply branch includes an external mobile power supply, the output end of which is electrically connected to the power supply terminals of the temperature monitor, cooling actuator, and control component, respectively, to provide independent offline power supply for the device.

[0032] In this embodiment, a dual-branch switchable compatible power supply architecture is designed to address the pain point of different power supply conditions for presses with different configurations in the automotive stamping workshop. The two independent power supply branches cover all working conditions of the presses, whether they have reserved power supply interfaces or not, so as to achieve rapid deployment of the equipment without any barriers. The first power supply branch uses Harding heavy-duty connectors, a common component in the mold industry, as the core of the power transfer. These connectors are vibration-resistant, oil-resistant, have a high protection level, are easy to plug and unplug, and can stably transmit large currents. They are perfectly suited to the harsh production environment of the stamping workshop, characterized by high temperature, high vibration, and high oil content. They can directly reuse the standardized power supply interface reserved on the press without any modification to the press's original electrical circuit. This allows the press's stable operating current to be connected to the equipment control system, ensuring a continuous and stable power supply for the equipment during continuous production. The second power supply branch uses a rechargeable external mobile power supply as an independent power source. This is suitable for situations where older presses do not have a reserved standardized power supply interface, temporary mold change production is required, or the press's power supply circuit is difficult to modify. It can provide independent power supply for the equipment throughout the entire process without modifying the existing electrical facilities in the workshop, significantly reducing the on-site deployment threshold and modification costs of the equipment. This embodiment solves the industry pain points of traditional drawing die temperature control equipment, such as a single power supply scheme, inability to adapt to all types of stamping press conditions, high difficulty in on-site deployment, and high modification costs, through a dual-branch compatible power supply design. It enables the equipment to be quickly adapted and deployed in different stamping production lines. At the same time, the independent design of the two power supply branches can effectively avoid the interference of press power supply circuit fluctuations on the equipment temperature control accuracy, further ensuring the operational stability and reliability of the automatic temperature control system, and avoiding the risk of temperature control failure and batch forming defects of parts due to power outages or power fluctuations.

[0033] Secondly, embodiments of this application provide a temperature control method based on an automatic temperature control device for drawing dies as described in some of the above embodiments, which includes the following steps: S100: The real-time temperature signal collected by the temperature monitor is transmitted to the control component. The control component compares the real-time temperature with the preset temperature control threshold. The temperature control threshold includes an upper temperature threshold for triggering cooling start and a lower temperature threshold for triggering cooling termination. S200: If the real-time temperature reaches or exceeds the preset upper temperature threshold, the control component calculates the target flow rate of the cooling medium required based on the total heat generated by the drawing die, and outputs the corresponding opening control signal to the cooling execution component based on the target flow rate. S300: If the real-time temperature drops to or below the preset lower limit threshold, the control component outputs a cut-off signal to the cooling execution component, and the cooling execution component shuts off the medium delivery path.

[0034] In this embodiment, a hysteresis closed-loop temperature control logic is constructed, consisting of "real-time temperature comparison - dynamic flow calculation for over-temperature - automatic stop when cooling is achieved." Using the real-time temperature of the mold cavity as the sole feedback basis, a stable temperature control hysteresis range is established through upper and lower temperature thresholds, effectively avoiding frequent start-stop of cooling actuators at critical temperature points. Simultaneously, the target flow rate of the cooling medium is dynamically calculated based on the real-time total heat generated by the drawing die, replacing the traditional fixed flow rate cooling method and achieving dynamic and precise matching between the cooling supply and the heat generated by the mold. This achieves fully automated closed-loop temperature control of the drawing die stamping process, requiring no manual intervention throughout and perfectly adapting to the production cycle of continuous high-speed stamping. The hysteresis temperature control logic avoids equipment wear caused by frequent valve start-stops, extending equipment lifespan. Furthermore, the dynamic flow rate calculation based on the total heat generated ensures that the mold temperature remains stable within the preset process range, solving the industry pain points of low temperature control accuracy and mold temperature runaway leading to defects in batch parts, as in traditional solutions. It also significantly reduces the ineffective consumption of cooling medium, achieving the dual effects of high-precision temperature control and energy saving.

[0035] In conjunction with the second aspect, in one implementation, S200 includes the following steps: S201: When the real-time temperature reaches or exceeds the preset upper temperature threshold, the control component retrieves the preset stable working temperature of the mold and the preset cooling time that are bound to the upper temperature threshold. S202: Based on the mass of the pressure ring, the specific heat capacity of the casting, and the temperature difference between the initial ambient temperature of the mold and the preset stable working temperature of the mold, the first part of the heat generated by the temperature difference of the mold is calculated. S203: Based on the real-time collected pressure of the blank holder, the friction coefficient between the sheet and the die, the press stamping speed, and the preset cooling time, the second part of the heat generated by the friction between the sheet and the die during the sheet drawing process is calculated. S204: Based on the first part of the heat and the second part of the heat, the total heat generated during the drawing die stamping process is obtained.

[0036] In this embodiment, the total heat generated during the drawing die stamping process is broken down into two core heat sources for precise quantitative calculation, fully covering the heat generation scenario of the entire die process: The first part is the heat generated by the temperature difference in the mold, which is the basic heat generated when the mold heats up from the initial ambient temperature to the preset stable operating temperature. The calculation formula is: E1=m·c p ·ΔT1, where E1 is the heat generated by the temperature difference, m is the mass of the pressure ring, and c p The specific heat capacity of the mold casting is ΔT1 = T2 - T1, where T2 is the preset stable working temperature of the mold and T1 is the initial ambient temperature of the mold. The second part is the frictional heat generated by the die, which is the dynamic heat generated by the high-speed friction between the sheet metal and the working surface of the die during the sheet metal drawing process. The calculation formula is: E2=μ·N·v·t, where E2 is the frictional heat generated, μ is the friction coefficient between the sheet metal and the die, N is the pressure of the blank holder, v is the stamping speed of the press, and t is the preset cooling time. The total heat generated during the drawing die stamping process that needs to be carried away by the cooling medium is: Etotal = E1 + E2. By disassembling the heat sources of the mold and performing full-scenario quantitative calculations, the system fully covers the two core heat sources: basic heat generation during mold heating and dynamic frictional heat generation during continuous stamping. This solves the problem that traditional temperature control solutions cannot accurately quantify the real-time heat generation conditions of the mold, providing accurate input for the subsequent precise calculation of the target flow rate of the cooling medium. This fundamentally improves the temperature control accuracy and the rationality of the cooling flow rate matching of the temperature control system.

[0037] In conjunction with the second aspect, in one implementation, at S200, the following step is further included: S205: Obtain the specific heat capacity and cooling gas inlet temperature of the cooling gas, and calculate the heat exchange temperature difference between the mold stable operating temperature and the cooling gas inlet temperature by combining the preset mold stable operating temperature bound to the upper temperature threshold. S206: Based on the principle of thermal balance, determine the total heat that the cooling gas can absorb within the preset cooling time, and match it with the total heat generated that needs to be carried away by the cooling medium during the stamping process of the drawing die. S207: Based on the above heat balance matching relationship, combined with the specific heat capacity of the cooling gas, the heat exchange temperature difference, and the preset cooling time, the target delivery flow rate of the cooling gas is calculated.

[0038] In this embodiment, based on the core principle of thermodynamic thermal balance, a complete equivalence relationship is established between the heat absorbed by the cooling gas and the total heat generated by the mold, enabling accurate derivation and calculation of the target flow rate of the cooling medium. First, calculate the heat exchange temperature difference between the mold and the cooling medium: ΔT2 = T2 - T in , among which, T in ΔT2 is the inlet temperature of the cooling gas, and ΔT2 is the heat exchange temperature difference between the stable working temperature of the mold and the inlet temperature of the cooling gas. Further clarify the total heat that the cooling gas can absorb within the preset cooling time. The calculation formula is: E3=m_gas·t·c_pgas·ΔT2, where m_gas is the target mass flow rate of the cooling gas, c_pgas is the specific heat capacity of the cooling gas, and t is the preset cooling time. Based on the principle of heat balance, the total heat absorbed by the cooling gas is exactly equal to the total heat generated by the mold, i.e., E3 = Etotal. Substituting these values ​​into the formula, we can derive the final calculation formula for the target flow rate of the cooling gas: m_gas=(m·c p ·ΔT1+μ·N·v·t) / (c_pgas·t·ΔT2); By using the principle of thermal balance, the flow rate of the cooling medium is accurately quantified and calculated, so that the cooling supply is perfectly matched with the real-time heating conditions of the mold. This avoids problems such as insufficient mold cooling and temperature runaway caused by insufficient cooling flow, as well as energy waste and poor sheet forming caused by excessive cooling flow and mold overcooling. It completely solves the core pain points of low temperature control accuracy and high energy consumption of traditional fixed flow cooling, and further improves the accuracy and economy of closed-loop temperature control.

[0039] In conjunction with the second aspect, one implementation also includes the following steps: S000: Based on the total heat generated during the drawing die stamping process, combined with the heat transfer characteristics of the cooling medium and the preset cooling time, the total design length of the cooling pipeline structure is determined by calculation using the principle of thermal balance.

[0040] In this embodiment, the pre-parametric pre-design of the cooling pipeline structure is completed before the mold goes into production. Using the total heat generated during the drawing die stamping process as the core design basis, and combining the heat transfer characteristics of the cooling medium with the preset cooling time, the total heat transfer capacity required by the cooling pipeline is determined through the principle of thermal balance. This leads to the derivation of the total design length of the cooling pipeline, ensuring that the hardware heat dissipation capacity of the cooling pipeline is perfectly matched to the mold's heating conditions. This pre-parameter pre-design of the cooling pipeline ensures, from a hardware perspective, that the heat transfer capacity of the cooling pipeline structure can match the maximum heating conditions of the mold stamping process. This avoids the problems of insufficient heat transfer capacity and substandard cooling effect caused by traditional cooling pipeline designs based on experience. It provides a reliable hardware foundation for the subsequent implementation of the closed-loop temperature control method, further improving the stability and reliability of the equipment's temperature control.

[0041] In conjunction with the second aspect, in one implementation, S000 includes the following steps: S001: Obtain the convective heat transfer coefficient of the cooling gas to the mold cast iron material and the preset pipe diameter parameters of the cooling pipe. Combine the preset stable working temperature of the mold and the cooling gas inlet temperature, which are bound to the upper limit temperature threshold, to calculate the heat exchange temperature difference between the stable working temperature of the mold and the cooling gas inlet temperature. S002: Based on the principle of thermal balance, determine the total heat that the cooling pipeline needs to remove within the preset cooling time, and match it with the total heat generated by the cooling medium that needs to be removed during the stamping process of the drawing die. S003: Based on the above heat balance matching relationship, combined with the convective heat transfer coefficient of the cooling gas, the heat transfer temperature difference and the preset cooling time, the total heat transfer area required for the cooling pipeline is calculated. S004: Calculate the total design length of the cooling pipe structure based on the preset pipe diameter parameters and total heat transfer area of ​​the cooling pipe.

[0042] In this embodiment, the core heat exchange temperature difference between the mold and the cooling medium is first clearly defined, and the calculation formula is completely reused with the overall temperature control parameter system: ΔT2=T2-T in In the formula: ΔT2 is the heat exchange temperature difference between the stable operating temperature of the mold and the inlet temperature of the cooling gas; T2 is the preset stable operating temperature of the mold, which is bound to the upper temperature threshold; T in This is to cool the gas inlet temperature; Simultaneously acquire the convective heat transfer coefficient h of the cooling gas to the cast iron mold material and the preset pipe diameter d of the cooling pipe. Based on the above parameters, determine the rated heat dissipation capacity per unit area of ​​the cooling pipe. The calculation formula is as follows: q=h·ΔT2 In the formula: q is the rated heat dissipation capacity of the cooling pipe per unit time and per unit area; h is the convective heat transfer coefficient of the cooling gas to the cast iron material of the mold. Based on the thermodynamic principle of thermal balance, the total heat that the cooling pipes can remove within a preset cooling time must be perfectly matched with the total heat generated by the cooling medium during the drawing die stamping process. The core formula for thermal balance is: E_pipe = E_total In the formula: E_pipe is the total heat that the cooling pipe can remove within the preset cooling time; E_total is the total heat generated during the stamping process of the drawing die, and E_total = E1 + E2, where E1 is the first part of the heat generated by the temperature difference of the die, and E2 is the second part of the heat generated by the friction of the sheet metal during drawing, which is completely consistent with the heat generation calculation system of the aforementioned steps S201-S204. Based on Newton's law of cooling, the total heat transfer of a cooling pipe is positively correlated with the total heat transfer area, the heat dissipation capacity per unit area, and the preset cooling time. The calculation formula is as follows: E_tube = q·A·t = h·A·ΔT²·t In the formula: A is the total heat transfer area required for the cooling pipeline; t is the preset cooling time, which is completely reused from the preset cooling time in the aforementioned cooling flow calculation step; Combining the aforementioned heat balance formula Epipe = Etotal, the final calculation formula for the total heat transfer area of ​​the cooling pipes is derived through modification: A = E_total / (h·ΔT²·t) = (m·c) p ·ΔT1+μ·N·v·t) / (h·ΔT2·t) In the formula: m is the mass of the blank holder, c p ΔT1 is the specific heat capacity of the mold casting, ΔT1 is the temperature difference between the initial ambient temperature of the mold and the preset stable working temperature, μ is the friction coefficient between the sheet metal and the mold, N is the pressure of the blank holder, and v is the press stamping speed. All of these are completely consistent with the parameter definitions of the aforementioned heat generation calculation formula. The cooling piping uses circular cross-section tubes, and its total heat transfer area is linearly related to the pipe diameter and total design length. The general formula for calculating the heat transfer area of ​​a circular tube is: A=π·d·L Where: d is the preset diameter of the cooling pipe; L is the total design length of the cooling pipe structure; π is the constant of pi; By transforming the above formula for total heat transfer area and substituting it into the formula for calculating total heat transfer area derived from heat balance, we finally obtain a precise quantitative calculation formula for the total design length of the cooling pipes: L=A / (π·d)=(m·c p ·ΔT1+μ·N·v·t) / (π·d·h·ΔT2·t) Through progressive, full-chain quantitative calculations, a parameter system fully unified with mold heat generation and cooling flow calculations was constructed. This enabled precise and standardized design of the total length of cooling pipes, completely replacing the traditional, experience-based, extensive pipe design approach used in the automotive mold industry. On one hand, by deeply binding the heat exchange capacity of the pipe hardware with the actual heat generation conditions of the mold through the principle of thermal balance, the design ensures that the heat exchange capacity of the cooling pipes can fully cover the maximum heat generation requirements of the mold stamping process. This avoids both insufficient heat exchange capacity and substandard cooling effect caused by pipes that are too short, and increased mold modification costs, excessive flow resistance, and ineffective loss of cooling capacity caused by pipes that are too long. On the other hand, the core parameters of the entire calculation process are fully reused with the closed-loop temperature control parameters in the production stage, realizing a closed-loop logic of "pre-matching in the design stage - dynamic control in the production stage." This significantly improves the rationality of the cooling pipe design and the actual heat exchange efficiency, providing a reliable hardware foundation for the subsequent implementation of closed-loop automatic temperature control of the drawing die, and further enhancing the temperature control stability and versatility of the entire solution.

[0043] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0044] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0045] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. An automatic temperature control device for drawing dies, characterized in that, It includes: Temperature monitor, used to collect temperature signals from the surface of the drawing mold cavity; Cooling piping structure, which is used to be embedded in the cavity of the drawing mold; A cooling actuator, which is connected to the cooling piping structure and is used to provide cooling medium to be delivered into the cooling piping structure; A control component is connected to the temperature monitor and the cooling execution component, and is used to receive the temperature signal collected by the temperature monitor, output a control signal to the cooling execution component according to a preset temperature threshold, and regulate the supply opening of the cooling execution component.

2. The automatic temperature control equipment for drawing dies as described in claim 1, characterized in that, The cooling actuator includes a pneumatic solenoid valve, a vortex cooling cylinder, and a compressed air source; The pneumatic solenoid valve is connected between the vortex cooling cylinder and the compressed air source, and is used to receive the control signal from the control component to realize on / off switching and opening degree adjustment. The vortex cooling cylinder is used to convert the compressed air from the compressed air source into a low-temperature cold airflow, which is then transported to the cooling pipeline structure as a cooling medium.

3. The automatic temperature control equipment for drawing dies as described in claim 1, characterized in that, The control components include a temperature threshold setting module, a temperature display module, and a signal control module; The temperature threshold setting module is used to preset the temperature control threshold of the drawing model cavity, the temperature display module is used to visualize the temperature signal collected by the temperature monitor, and the signal control module is used to output the corresponding control signal to the cooling execution component according to the temperature signal.

4. The automatic temperature control equipment for drawing dies as described in claim 1, characterized in that, The cooling pipe structure includes two parallel cooling pipes, which are embedded in the drawing mold cavity and distributed on the two opposite inner sidewalls of the drawing mold cavity. One port of the cooling pipe is connected to the cooling execution component, and the other port is an exhaust port.

5. The automatic temperature control equipment for drawing dies as described in claim 1, characterized in that, The temperature monitor includes an infrared temperature sensor, which is used to acquire temperature signals from the surface of the drawing mold cavity in a non-contact manner and transmit the temperature signals to the control component in real time.

6. A temperature control method based on the automatic die temperature control apparatus according to any one of claims 1 to 5, characterized by, It includes the following steps: The real-time temperature signal collected by the temperature monitor is transmitted to the control component, which then compares the real-time temperature with the preset temperature control threshold. If the real-time temperature reaches or exceeds the preset upper temperature threshold, the control component calculates the target flow rate of the cooling medium required based on the total heat generated by the drawing die, and outputs the corresponding opening control signal to the cooling execution component based on the target flow rate. If the real-time temperature drops to or below the preset lower temperature threshold, the control component outputs a cut-off signal to the cooling execution component, which then shuts off the media delivery path.

7. The temperature control method of the automatic temperature control equipment for drawing dies as described in claim 6, characterized in that, If the real-time temperature reaches the preset upper temperature threshold, the control component calculates the target flow rate of the cooling medium based on the total heat generated by the drawing die, including: When the real-time temperature reaches or exceeds the preset upper temperature threshold, the control component retrieves the preset stable working temperature of the mold and the preset cooling time that are bound to the upper temperature threshold. The first part of the heat generated by the temperature difference of the mold is calculated based on the mass of the pressure ring, the specific heat capacity of the casting, the temperature difference between the initial ambient temperature of the mold and the preset stable working temperature of the mold. Based on the real-time collected pressure of the blank holder, the friction coefficient between the sheet and the die, the press stamping speed, and the preset cooling time, the second part of the heat generated by the friction between the sheet and the die during the sheet drawing process is calculated. Based on the first part of the heat and the second part of the heat, the total heat generated during the drawing die stamping process is obtained.

8. The temperature control method of the automatic temperature control equipment for drawing dies as described in claim 6, characterized in that, If the real-time temperature reaches the preset upper temperature threshold, the control component calculates the target flow rate of the cooling medium based on the total heat generated by the drawing die, including: The specific heat capacity and inlet temperature of the cooling gas are obtained, and the heat exchange temperature difference between the stable working temperature of the mold and the inlet temperature of the cooling gas is calculated by combining the preset stable working temperature of the mold with the upper limit threshold temperature. Based on the principle of thermal balance, the total heat that the cooling gas can absorb within the preset cooling time is determined to match the total heat generated by the cooling medium during the stamping process of the drawing die. Based on the above thermal balance matching relationship, combined with the specific heat capacity of the cooling gas, the heat exchange temperature difference, and the preset cooling time, the target delivery flow rate of the cooling gas is calculated.

9. The temperature control method of the drawing die temperature automatic control apparatus according to claim 6, wherein It also includes the following steps: Based on the total heat generated during the drawing die stamping process, combined with the heat transfer characteristics of the cooling medium and the preset cooling time, the total design length of the cooling pipeline structure is calculated and determined by the principle of heat balance.

10. The temperature control method of the automatic temperature control equipment for drawing dies as described in claim 9, characterized in that, The total heat generated during the drawing die stamping process, combined with the heat transfer characteristics of the cooling medium and the preset cooling time, is used to calculate and determine the total design length of the cooling pipe structure based on the principle of heat balance, including: The heat transfer coefficient of the cooling gas to the cast iron material of the mold and the preset pipe diameter parameters of the cooling pipe are obtained. Combined with the preset stable working temperature of the mold and the inlet temperature of the cooling gas, which are bound to the upper limit threshold of the temperature, the heat exchange temperature difference between the stable working temperature of the mold and the inlet temperature of the cooling gas is calculated. Based on the principle of thermal balance, the total heat that the cooling pipe needs to remove within the preset cooling time is determined to match the total heat generated by the cooling medium during the drawing die stamping process. Based on the above heat balance matching relationship, combined with the convective heat transfer coefficient of the cooling gas, the heat transfer temperature difference and the preset cooling time, the total heat transfer area required for the cooling pipeline is calculated. The total design length of the cooling pipe structure is calculated based on the preset pipe diameter parameters and total heat transfer area of ​​the cooling pipe.

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