A precision stamping device and method for heat exchange plates with in-situ degassing and oil removal functions

Abstract

This invention discloses a precision stamping device and method for heat spreader plates with in-situ degassing and degreasing functions, relating to the field of heat spreader plate stamping technology. The invention includes a sealed chamber module for establishing a partially sealed stamping chamber at the die-joining position of the punch and die. An atmosphere control module controls the evacuation of the stamping chamber via a first control valve and the injection of protective gas into the chamber via a second control valve. A heating system heats the die and / or workpiece located within the stamping chamber. A control system controls the operation of the drive mechanism, the sealed chamber module, the atmosphere control module, and the heating system. The heating system features a staged heating mode: heating the workpiece to a first preset temperature before stamping, and heating it to a second preset temperature higher than the first preset temperature and holding it at that temperature after stamping. This invention ensures stamping accuracy while removing contaminants from the workpiece surface in-situ during stamping, reducing the burden on the annealing furnace and improving subsequent annealing efficiency.

Description

Technical Field

[0001] This invention relates to the field of heat exchanger stamping technology, specifically to a precision stamping device and method for heat exchangers with in-situ degassing and degreasing functions. Background Technology

[0002] A vapor chamber, as a highly efficient heat transfer element, is a passive heat dissipation component that utilizes the principle of phase change (liquid absorbs heat and evaporates, gas releases heat and condenses) for efficient heat transfer. It is widely used in electronic equipment, new energy vehicles, aerospace, and other fields. Its core function is to rapidly diffuse and transfer concentrated heat to heat dissipation components through its own structure, thereby ensuring the stable operation of the equipment. The performance of a vapor chamber depends not only on its materials but also on its manufacturing process, with stamping forming being one of the mainstream technologies for vapor chamber processing.

[0003] During the stamping process of heat exchangers, stamping lubricant is typically applied to the sheet metal surface to reduce the coefficient of friction between the die and the sheet metal, decrease stamping pressure, and prevent scratches on the workpiece surface and die wear. These lubricants are mostly mineral oils, synthetic oils, or emulsions, with complex compositions including base oils, extreme pressure additives, and rust inhibitors. After stamping, they remain as an oil film on the workpiece surface, especially in structurally complex areas such as recesses and crevices. Furthermore, the oil film comes into direct contact with air, and water vapor, dust, and volatile organic compounds (VOCs) from the production environment (such as solvent vapors and hydrocarbons from lubricating greases in the workshop) are adsorbed onto the workpiece surface, forming composite contaminants.

[0004] If the aforementioned surface contaminants are not effectively treated, they will negatively impact subsequent annealing processes and the final performance of the heat spreader. Annealing is a crucial step in heat spreader manufacturing. Its purpose is to eliminate internal stress generated during stamping, refine grains, and improve material mechanical properties through high-temperature heating and holding, thereby ensuring the dimensional stability and thermal conductivity of the heat spreader. However, residual lubricating oil and hydrocarbons on the workpiece surface will decompose, carbonize, or oxidize under the high-temperature environment of the annealing furnace. On the one hand, the volatile gases produced by decomposition may alter the preset atmosphere inside the furnace, leading to oxidation, decarburization, or the formation of discolored spots on the workpiece surface, affecting surface quality and thermal conductivity. On the other hand, incompletely volatilized carbonaceous residues will deposit on the furnace inner wall, heating elements, and furnace bottom, forming carbon deposits. This not only reduces the heat transfer efficiency of the furnace and causes uneven temperature distribution but also increases the frequency of equipment cleaning and maintenance costs. In severe cases, it may even cause short circuits in heating elements or localized overheating of the furnace, shortening the equipment's lifespan. Simultaneously, adsorbed water vapor may react with the workpiece surface at high temperatures to form an oxide layer, further reducing the thermal conductivity of the heat spreader.

[0005] To address these issues, existing technologies typically add a separate cleaning process after stamping and before annealing, such as solvent cleaning, ultrasonic cleaning, or high-temperature degreasing. However, this not only increases the complexity and time cost of the production process but also brings environmental pressure and additional wastewater treatment problems. For example, solvent cleaning requires the use of cleaning agents such as kerosene and alcohol, which not only increases production costs but may also cause secondary pollution due to cleaning agent residue. Furthermore, the treatment of cleaning wastewater must meet environmental protection requirements, further increasing the complexity of the process. Ultrasonic cleaning has limited effectiveness in removing contaminants from gaps and blind holes in complex workpiece structures, and the workpiece surface still absorbs moisture and impurities from the air after cleaning. Although high-temperature degreasing can evaporate grease through heating, it requires additional heating equipment, and the separate degreasing process extends the production cycle and reduces overall production efficiency.

[0006] Therefore, properly removing surface contaminants from the heat exchanger before annealing, and reducing the total amount of contaminants entering the annealing furnace, has become a pressing technical problem in this field. Summary of the Invention

[0007] The purpose of this invention is to provide a precision stamping device and method for heat spreaders with in-situ degassing and degreasing functions, so as to remove contaminants from the surface of the workpiece in-situ while ensuring stamping accuracy, thereby reducing the burden on the annealing furnace and improving the efficiency of subsequent annealing.

[0008] The technical solution adopted in this invention is as follows:

[0009] A precision stamping device for heat spreaders with in-situ degassing and degreasing functions includes an upper die base, a lower die base, and a driving mechanism for driving the upper die base to close with the lower die base. The upper die base is provided with a punch, and the lower die base is provided with a die that mates with the punch. The precision stamping device for heat spreaders with in-situ degassing and degreasing functions further includes: a sealed chamber module disposed between the upper die base and the lower die base, used to establish a partially sealed stamping chamber at the die-closing position of the punch and the die; and an atmosphere control module connected to the stamping chamber, which controls the atmosphere through a first control valve. The system includes: evacuating the stamping chamber and filling it with protective gas via a second control valve; a heating system for heating the die and / or workpiece located within the stamping chamber; and a control system for controlling the operation of the drive mechanism, the sealed chamber module, the atmosphere control module, and the heating system. The heating system, controlled by the control system, executes a phased heating mode: heating the workpiece to a first preset temperature before stamping, and heating the workpiece to a second preset temperature higher than the first preset temperature and maintaining that temperature after stamping.

[0010] In this technical solution, a partially sealed stamping chamber is directly constructed at the stamping station using a sealed chamber module, integrating an atmosphere control and heating system, all managed collaboratively by a unified control system. The atmosphere control module first evacuates the stamping chamber to remove air and impurities such as moisture, oxygen, and hydrocarbons, then fills it with a protective gas to replace the atmosphere within the chamber. This effectively avoids secondary contamination of the workpiece surface by airborne pollutants and utilizes the chemical inertness of protective gases such as nitrogen and argon to inhibit oxidation reactions and prevent the formation of an oxide layer on the workpiece surface. Combined with the heating system, a staged heating mode is implemented. First, before stamping, the workpiece is heated to a relatively low first preset temperature. This temperature aims to soften the workpiece material, eliminate internal stress, and optimize the stamping quality, while avoiding excessive softening that could lead to wrinkles or tears. Then, immediately after stamping, the workpiece is heated to a higher second preset temperature and held at that temperature. This allows the lubricating oil, moisture, and hydrocarbons adsorbed on the surface of the stamped workpiece to evaporate rapidly, while the protective gas atmosphere promptly removes the volatiles, preventing them from re-adhering to the workpiece surface. Therefore, this device enables the continuous completion of three processes—stamping, preheating, and high-temperature purification—within the original stamping station of a stamping unit. This fundamentally improves the problem of contaminated workpieces polluting subsequent expensive annealing furnace heat treatment equipment. It provides semi-finished products with better surface conditions for subsequent high-temperature annealing and final encapsulation welding. Workpieces entering the annealing furnace no longer need to deal with large amounts of oil and water vapor. The annealing furnace can reach the required high vacuum level more quickly and focus most of its heat energy and process time on completing its core task, reducing the load on the annealing furnace. Moreover, because the furnace is less affected by contaminants, the vacuuming time and air exchange time can be shortened. Theoretically, the annealing heating rate can be appropriately increased without worrying about workpiece surface deterioration, thereby further shortening the entire annealing cycle.

[0011] The sealed chamber module includes: a fixed platform, fixedly mounted on the lower die base and surrounding the die cavity, the fixed platform having a material conveying channel for conveying workpieces to the stamping station between the punch and the die cavity via an external conveying structure; a lifting sealing ring, surrounding the die cavity and capable of vertically lifting relative to the lower die base, the top of the lifting sealing ring having a sealing element; and a flexible sealing body, the upper and lower ends of which are respectively sealed to the upper die base and the fixed platform; wherein, the lifting sealing ring is controlled by the control system to rise so that the sealing element at its top presses against the bottom surface of the fixed platform, thereby forming the stamping chamber together with the fixed platform and the flexible sealing body.

[0012] In this technical solution, a reliable dynamic sealing closed stamping chamber structure is achieved through a combination of a fixed platform, a lifting sealing ring, and a flexible sealing body. The lifting sealing ring, through its pressing action with the fixed platform, solves the problem of creating a reliable seal in work areas requiring external conveying structures to enter and exit for material feeding. When sealing is needed, the lifting sealing ring rises and presses against the fixed platform, forming a closed chamber surrounding the stamping station together with the flexible sealing body. When loading and unloading are needed, it lowers to create space, allowing external conveying structures to feed and retrieve workpieces through the material conveying channel, providing a basis for in-situ processing. The sealing element ensures the sealing performance of the stamping chamber, ensuring that the atmosphere control module and heating system effectively act on the workpiece. Simultaneously, the flexible sealing body adapts to the movement of the upper die base, avoiding interference with the stamping action, thus achieving compatibility between the closed environment and the stamping process.

[0013] The flexible sealing body is a metal bellows. The top of the fixed platform is provided with a first flange face. The lower end of the metal bellows is detachably and sealed to the first flange face through a first transition connector. The bottom of the upper mold base is provided with a second flange face. The upper end of the metal bellows is detachably and sealed to the second flange face through a second transition connector.

[0014] In this technical solution, a metal bellows is used as a flexible sealing body. The excellent fatigue resistance and high temperature resistance of the metal bellows can withstand the frequent expansion and contraction movements during the stamping process. The upper and lower ends of the metal bellows are detachably connected to the flange face through transition connectors, which ensures the sealing of the connection. At the same time, this vulnerable part, the metal bellows, can be easily replaced after it reaches the end of its service life, reducing the long-term maintenance cost and difficulty of the equipment, and avoiding the irreplaceable problem caused by direct welding to the fixed table and upper mold base.

[0015] The fixed platform includes a top annular platform and multiple legs supporting the annular platform and the lower mold base, with the material conveying channel formed between adjacent legs.

[0016] In this technical solution, the fixed platform is a frame structure composed of an annular platform and legs. The annular platform and legs of the fixed platform ensure the stability of the support for the flexible sealing body and the lifting sealing ring. At the same time, the material conveying channel formed between adjacent legs provides space for workpiece conveying, avoids structural interference, and the lightweight design reduces heat capacity, which is conducive to the rapid heating of the heating system and improves temperature control efficiency.

[0017] The atmosphere control module is controlled by the control system and has a gas washing mode and a dynamic flushing mode: in the gas washing mode, the atmosphere control module performs the action of first evacuating and then filling with protective gas at least twice in a cycle; in the dynamic flushing mode, the atmosphere control module opens the first control valve and the second control valve and adjusts the opening degree so that the protective gas forms a continuous flow in the stamping chamber, so as to carry the volatiles away from the stamping chamber.

[0018] This technical solution employs an intelligent atmosphere control strategy, utilizing two modes—gas scrubbing and dynamic flushing—to ensure optimal process performance. The gas scrubbing mode, through multiple cycles of vacuuming and gas filling, efficiently and thoroughly replaces the air in the chamber with pure protective gas, creating an oxygen-free environment for the stamping and heating processes. This prevents moisture and oxygen in the air from interfering with the stamping and decontamination processes. The dynamic flushing mode, by simultaneously controlling the opening of the first and second control valves during the heat preservation stage, establishes a continuous flow of protective gas within the stamping chamber. This airflow continuously carries away the heated and volatilized contaminant molecules from the workpiece surface and the stamping chamber, achieving continuous purification and preventing the re-condensation of contaminants within the chamber and on the workpiece surface, thus enhancing the degassing and degreasing effects.

[0019] The atmosphere control module includes a vacuum pump, a protective gas source, a vacuum pumping line, and an air inlet line. The vacuum pump is connected to the stamping chamber through the vacuum pumping line, the protective gas source is connected to the stamping chamber through the air inlet line, the first control valve is connected to the fluid path of the vacuum pumping line, and the second control valve is connected to the fluid path of the air inlet line.

[0020] In this technical solution, the combination of a vacuum pump, a protective gas source, a vacuuming pipeline, an air inlet pipeline, and two control valves enables precise control of the vacuuming and protective gas filling of the pressurization chamber. The structure is simple and easy to operate. The first control valve and the second control valve independently control the vacuuming and air inlet paths, ensuring stable switching between the gas washing mode and the dynamic flushing mode, and improving the reliability of atmosphere control.

[0021] The heating system includes a heating element embedded in the lower mold base, and the heating element is a heating tube arranged around the concave mold.

[0022] In this technical solution, the heating element adopts a heating tube arranged around the die cavity and embedded in the lower die base. It can evenly transfer heat to the workpiece through the die cavity, realizing precise heating of the workpiece. The surrounding layout ensures uniform heating of the workpiece, avoids local excessively high or low temperatures, and improves the effect of staged heating. This layout does not interfere with the normal stamping action and ejection function of the die. It has a compact structure and is suitable for integrating heating functions in dies with limited space.

[0023] The lower mold base is also provided with a heat-conducting ring and a heat-insulating structure. The heat-conducting ring is sleeved on the outer periphery of the die, the heating tube surrounds and contacts the outer periphery of the heat-conducting ring, and the heat-insulating structure is provided on the side of the heating tube away from the die.

[0024] In this technical solution, the thermal management performance of the heating system is further optimized. The heat-conducting ring is tightly fitted around the die, increasing the heat conduction contact area between the heating tube and the die. This allows for rapid and uniform heat transfer to the die, eliminating the risk of local overheating or overcooling and making the workpiece heat up more quickly and evenly. Meanwhile, the heat insulation structure set on the side of the heating tube away from the die effectively blocks heat from being transferred to other parts such as the die base and the press worktable. Almost all the heat is conducted to the die and workpiece through the heat-conducting ring, which reduces energy waste, lowers equipment operating costs, and prevents heat conduction from causing thermal damage or thermal interference to other precision components of the equipment.

[0025] The present invention provides a precision stamping method for heat spreaders, which employs the precision stamping device for heat spreaders with in-situ degassing and degreasing functions as described above, and includes the following steps:

[0026] The sealed chamber module creates a partially sealed stamping chamber at the mold closing position of the punch and die;

[0027] The atmosphere control module enters the gas washing mode: it performs multiple vacuuming and protective gas filling operations on the stamping chamber to replace the gas in the stamping chamber with protective gas.

[0028] Before stamping, the die and workpiece in the stamping chamber are heated to the first preset temperature;

[0029] Stamping is performed under protective gas and a first preset temperature condition;

[0030] After stamping is completed, the punch and die remain in the closed state, and the die and the formed workpiece in the stamping chamber are heated to a second preset temperature higher than the first preset temperature and kept at that temperature for a predetermined time.

[0031] In this technical solution, the method integrates multiple dispersed processes such as stamping, cleaning, preheating, and degassing into a continuous and automated process by establishing a sealed environment in situ at the stamping station, performing atmosphere replacement, and conducting staged heating and stamping. By establishing a sealed stamping chamber and replacing it with a protective gas through a gas washing mode, the influence of air pollutants is avoided; heating to a first preset temperature before stamping optimizes the stamping performance of the workpiece, and stamping under a protective gas atmosphere improves the forming accuracy; heating to a second preset temperature after stamping and holding it at that temperature efficiently promotes the volatilization of surface adsorbates, reducing the pollutant load on the subsequent annealing furnace. The overall process balances stamping quality and decontamination efficiency, achieving a highly efficient, clean, and high-quality precision manufacturing process.

[0032] During the heat preservation stage after stamping, the atmosphere control module enters the dynamic flushing mode: the first control valve and the second control valve are opened and the opening is adjusted so that the air intake flow of the second control valve is greater than the air extraction flow of the first control valve. Simultaneously, the vacuuming action and the filling of protective gas are performed, so that the protective gas forms a continuous flow state in the chamber, and the volatiles generated on the molded workpiece are discharged with the airflow.

[0033] In this technical solution, a dynamic flushing mode is activated during the heat preservation stage after stamping. The continuous flow of protective gas promptly removes volatiles from the chamber, preventing them from circulating within the chamber and re-adhering to the workpiece surface. This further enhances the thoroughness of degassing and degreasing, providing a cleaner workpiece surface for subsequent annealing and indirectly improving annealing quality. Furthermore, by ensuring that the intake flow rate of the second control valve is greater than the exhaust flow rate of the first control valve, any minor leaks in the stamping chamber will only result in gas leakage from the inside to the outside, preventing external air from entering and ensuring the purity of the protective atmosphere during the dynamic flushing process. Attached Figure Description

[0034] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings:

[0035] Figure 1 This is a schematic diagram of the structure of the precision stamping device for heat-spreading plates with in-situ degassing and degreasing functions provided in an embodiment of the present invention. Figure 1 It shows the state when the punch and die are open;

[0036] Figure 2 for Figure 1 Enlarged view of point A in the middle;

[0037] Figure 3 This is a schematic diagram of the structure of the precision stamping device for heat-spreading plates with in-situ degassing and degreasing functions provided in an embodiment of the present invention. Figure 2 It shows the state in which the punch and die are closed and the lifting sealing ring is pressed against the fixed table through the sealing element to form the stamping chamber;

[0038] Figure 4 This is a schematic diagram of the structure of the fixing platform provided in an embodiment of the present invention;

[0039] Figure 5 This is a cross-sectional view of the lifting sealing ring provided in an embodiment of the present invention.

[0040] List of components and reference numerals:

[0041] 10 Upper mold base, 11 Lower mold base, 12 Punch, 13 Die, 14 First control valve, 15 Second control valve, 16 Pressure plate, 17 Ejector, 18 Fixed platform, 181 Annular platform, 182 Support leg, 19 Lifting sealing ring, 191 Seal, 20 Flexible sealing body, 21 Vacuum pump, 22 Protective gas source, 23 Vacuum pumping pipeline, 24 Inlet pipeline, 25 Heating tube, 26 Heat conducting ring, 27 Heat insulation structure. Detailed Implementation

[0042] To more clearly illustrate the overall concept of the present invention, a detailed description will be provided below with reference to the accompanying drawings and examples.

[0043] Many specific details are set forth in the following description in order to provide a full understanding of the invention. However, the invention may also be practiced in other ways different from those described herein, and therefore the scope of protection of the invention is not limited to the specific embodiments disclosed below.

[0044] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection, an electrical connection, or a communication connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] In the description of this specification, references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of the invention. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] In embodiments of the present invention, such as Figures 1 to 5 As shown, a precision stamping device for heat spreaders with in-situ degassing and oil removal functions is provided. For ease of explanation and understanding, the following descriptions are based on the illustrated product structure. Of course, those skilled in the art will understand that the above structure is merely a specific example and illustrative illustration, and does not constitute a specific limitation on the technical solution provided by this invention.

[0047] like Figure 1 and Figure 3As shown, the precision stamping device for heat spreaders includes an upper die holder 10, a lower die holder 11, and a drive mechanism for driving the upper die holder 10 to close with the lower die holder 11. The upper die holder 10 is provided with a punch 12, and the lower die holder 11 is provided with a die 13 that mates with the punch 12. The precision stamping device for heat spreaders also includes a sealed chamber module, an atmosphere control module, a heating system, and a control system. The sealed chamber module is located between the upper die holder 10 and the lower die holder 11 and is used to create a partially sealed stamping chamber at the die-closing position of the punch 12 and the die 13. The atmosphere control module is connected to the stamping chamber and allows for... The first control valve 14 controls the evacuation of the stamping chamber and the second control valve 15 controls the filling of the stamping chamber with protective gas, such as nitrogen or argon; the heating system is used to heat the die 13 and / or workpiece located in the stamping chamber; the control system is used to control the operation of the drive mechanism, the sealed chamber module, the atmosphere control module and the heating system; wherein, the heating system is controlled by the control system to execute a staged heating mode: heating the workpiece to a first preset temperature before stamping, and heating the workpiece to a second preset temperature higher than the first preset temperature and holding it at that temperature after stamping. Figure 1 The image shows the state when the punch 12 and die 13 are open. Figure 3 The image shows the state when the punch 12 and die 13 are closed and the stamping chamber is constructed.

[0048] Specifically, the precision stamping device for heat-spreading sheets of the present invention can be applied to a stamping press specifically designed for heat-spreading sheet stamping, such as a multi-station progressive die stamping press. The precision stamping device constitutes the stamping station module of this stamping press. The upper die holder 10 can be mounted on the slide of the stamping press, and the upper die holder 10 is driven up and down by a drive mechanism to achieve die opening and closing. In actual production processing, after the strip enters the stamping press and is positioned, it is cut around the area to be formed to prepare for material flow. Then, after at least one pre-stretch, it enters this device for the stamping process. To improve the thermal conductivity and heat resistance of the die 13 and the punch 12, both can be made of tungsten carbide, die steel, or other suitable materials. In addition, as Figure 1 As shown, a pressure plate 16 can also be arranged around the punch 12. The upper end of the pressure plate 16 can be connected to the upper die holder 10 by a spring or other suitable elastic element, allowing the pressure plate 16 to float up and down. Before the punch 12 contacts the workpiece, the pressure plate 16 will first press down on the perimeter of the stamped area of ​​the workpiece, providing sufficient blank holder force to prevent wrinkling of the workpiece during the stretching process. In addition, as Figure 1As shown, an ejector 17 can also be provided in the center of the die 13. After stamping, the ejector 17 can rise under the drive of the drive structure and remove the formed workpiece from the die 13 for delivery to the next station. To ensure the vacuum level of the stamping chamber during vacuuming, appropriate sealing treatments can be performed at locations where there are likely to be fitting clearances, such as adding existing high-temperature resistant sealing rings or filling with existing high-temperature resistant sealing materials, without affecting the operation of the process.

[0049] In this invention, by setting a sealed chamber module between the upper mold base 10 and the lower mold base 11, a partially sealed stamping chamber can be formed at the mold closing position of the punch 12 and the die 13. This structure provides a closed space basis for subsequent atmosphere control and heat treatment, and avoids the entry of pollutants from the external environment that may affect the treatment effect.

[0050] The atmosphere control module can remove the original air and impurities such as water vapor, oxygen, and hydrocarbons contained in the stamping chamber by evacuating the first control valve 14. Then, protective gas is introduced through the second control valve 15, realizing the replacement of the atmosphere in the chamber. This not only prevents the pollutants in the air from causing secondary pollution to the surface of the workpiece, but also uses the inertness of the protective gas to isolate oxygen during the heating process, avoiding oxidation reaction of the workpiece during the staged heating, and ensuring the surface quality of the workpiece.

[0051] The heating system can directly heat the workpiece or indirectly heat it through heat conduction via the die 13. Controlled by the control system, the heating system executes a staged heating mode. First, before stamping, the workpiece is heated to a relatively low first preset temperature. This temperature reduces the yield strength of the workpiece material to a certain extent, thereby reducing the driving force required for stamping and reducing die wear. Simultaneously, it avoids excessive softening of the material due to excessive temperature, which could cause wrinkles or tears, ensuring that the size and shape of the heat spreader in the stamped form meet the requirements. Then, immediately after stamping, the workpiece is heated to a higher second preset temperature and held at that temperature. This allows the lubricating oil, moisture, and hydrocarbons adsorbed on the surface of the stamped workpiece to evaporate rapidly. Simultaneously, a protective gas atmosphere is used to promptly remove the volatiles, preventing them from re-adhering to the workpiece surface. The control system coordinates the control of each component, ensuring the orderly execution of the entire stamping, heating, and atmosphere conditioning process.

[0052] Therefore, this device enables the continuous completion of three processes—stamping, preheating, and high-temperature purification—within a single stamping station. This fundamentally improves the process of preventing contaminated workpieces from polluting subsequent expensive annealing furnace heat treatment equipment. It provides semi-finished products with better surface conditions for subsequent high-temperature annealing and final encapsulation welding. Workpieces entering the annealing furnace no longer need to be treated with large amounts of oil and water vapor. The annealing furnace can reach the required high vacuum level more quickly and focus most of its heat energy and process time on completing its core task, reducing the load on the annealing furnace. Moreover, because the furnace is less affected by contaminants, the vacuuming time and air exchange time can be shortened. Theoretically, the annealing heating rate can be appropriately increased without worrying about workpiece surface deterioration, thereby further shortening the entire annealing cycle.

[0053] Regarding the sealed chamber module, as a preferred embodiment of the present invention, such as Figure 1 and Figure 5 As shown, the sealed chamber module includes a fixed platform 18, a lifting sealing ring 19, and a flexible sealing body 20. The fixed platform 18 is fixedly mounted on the lower die base 11 and surrounds the die cavity 13. The fixed platform 18 is provided with a material conveying channel for conveying workpieces to the stamping station between the punch 12 and the die cavity 13 by an external conveying structure. The lifting sealing ring 19 surrounds the die cavity 13 and can be vertically lifted relative to the lower die base 11. The top of the lifting sealing ring 19 is provided with a sealing element 191. The upper and lower ends of the flexible sealing body 20 are respectively sealed to the upper die base 10 and the fixed platform 18. The lifting sealing ring 19 is controlled by the control system to rise so that the sealing element 191 at its top presses against the bottom surface of the fixed platform 18, thereby forming a stamping chamber together with the fixed platform 18 and the flexible sealing body 20. Figure 1 The image shows the lifting sealing ring 19 lowered and hidden inside the lower mold base 11. In this state, interference with the external conveying structure's workpiece feeding and receiving is avoided. Figure 3The image shows the state where the lifting sealing ring 19 rises, causing the sealing element 191 to abut and press against the fixed platform 18. The fixed platform 18 in the sealed chamber module is fixed on the lower mold base 11 and surrounds the die 13. The hollow area in the middle of the fixed platform 18 is used for the punch 12 and the die 13 to close. The material conveying channel set in the fixed platform 18 can facilitate the stable conveying of the workpiece to the stamping station between the punch 12 and the die 13 by external conveying structures (such as robots), ensuring the smoothness of workpiece conveying and avoiding jamming during the conveying process that affects production efficiency. The lifting sealing ring 19 surrounds the die cavity 13 and can be vertically lifted relative to the lower die base 11. When the lifting sealing ring 19 rises, its top seal 191 presses against the bottom surface of the fixed platform 18, thus forming a stamping chamber together with the fixed platform 18 and the flexible sealing body 20. This structural design simplifies the formation and opening of the stamping chamber. The seal 191 ensures the chamber's airtightness, reducing the risk of leakage of the protective gas introduced by the atmosphere control module. It also ensures the desired vacuum level is achieved during vacuuming. The seal 191 is preferably a high-temperature resistant sealing ring made of perfluoroether rubber. The upper and lower ends of the flexible sealing body 20 are respectively sealed to the upper die base 10 and the fixed platform 18, adapting to the up-and-down movement of the upper die base 10 during the stamping process. This avoids damage to the chamber's airtightness due to the movement of the upper die base 10, achieving compatibility between the sealed environment and the stamping action, and ensuring a stable protective gas atmosphere and temperature environment during the stamping process. Specifically, the lifting and lowering drive method of the lifting sealing ring 19 is not specifically limited or illustrated in this invention. For example, it can be driven by a cylinder, a hydraulic cylinder, or other suitable methods.

[0054] In a preferred embodiment, such as Figure 1As shown, the flexible sealing body 20 is a metal bellows. The top of the fixed platform 18 has a first flange face, and the lower end of the metal bellows is detachably and sealingly connected to the first flange face via a first transition connector. The bottom of the upper die holder 10 has a second flange face, and the upper end of the metal bellows is detachably and sealingly connected to the second flange face via a second transition connector. The metal bellows has good flexibility and high-temperature resistance, allowing it to adapt to the frequent up-and-down movement of the upper die holder 10 during the stamping process without easily being damaged, thus extending the service life of the sealing body. The first flange face at the top of the fixed platform 18 and the second flange face at the bottom of the upper die holder 10, together with the first and second transition connectors, enable the upper and lower ends of the metal bellows to be detachably and sealingly connected to the fixed platform 18 and the upper die holder 10. This connection method not only ensures the sealing performance of the connection, preventing leakage of protective gas and the entry of external air, but also facilitates disassembly and replacement when the metal bellows is damaged, reducing maintenance difficulty and cost. At the same time, the transition connector also enhances the stability of the connection, preventing the metal bellows from loosening due to vibration or other reasons during long-term use. Although the first flange face, second flange face, first transition connector, and second transition connector are not shown in the accompanying drawings, in a preferred embodiment, the first and second transition connectors can be flanges. The upper and lower flanges can be welded to the upper and lower ends of the metal bellows, respectively. The flanges at both ends are connected to the first and second flange faces, respectively, by bolts. A sealing gasket can also be provided between the connecting surfaces. The metal bellows can be made of materials such as stainless steel, nickel-based alloys, or titanium alloys.

[0055] In other embodiments, the flexible sealing body 20 can adopt other suitable structures besides metal bellows, such as high-temperature fluororubber composite seals, which are composed of multiple layers of high-temperature resistant fluororubber or silicone rubber and a metal skeleton, in the form of annular bellows or pleats, and can be flanged at both ends to the upper mold base 10 and the fixed platform 18; or a metal and rubber combined sealing body, which uses a thin metal plate as the main frame, and a high-temperature resistant rubber layer is attached to the inner or outer side of the metal pleats to form a composite structure of metal support combined with rubber sealing, and can be flanged at both ends to the upper mold base 10 and the fixed platform 18.

[0056] In a preferred embodiment, such as Figure 4As shown, the fixed platform 18 includes a top annular platform 181 and multiple legs 182 supporting the annular platform 181 and the lower die base 11, with a material conveying channel formed between adjacent legs 182. This structure ensures the stability of the fixed platform 18 in supporting the flexible seal 20 and the lifting seal ring 19, while reducing the overall weight of the fixed platform 18 and lowering material costs. The material conveying channel formed between adjacent legs 182 provides ample space for workpiece conveying, avoiding interference from the fixed platform 18 structure and ensuring that the workpiece can smoothly enter the stamping station. In addition, the lightweight structural design reduces the heat capacity of the fixed platform 18, so that the fixed platform 18 absorbs less heat when the heating system heats the die 13 and the workpiece, which is conducive to the rapid rise and stabilization of the temperature in the stamping cavity, improving heating efficiency and temperature control accuracy.

[0057] Regarding the atmosphere control module, in a preferred embodiment of the present invention, it is controlled by the control system and has a gas washing mode and a dynamic flushing mode: In the gas washing mode, the atmosphere control module performs the action of first evacuating and then filling with protective gas at least twice; in the dynamic flushing mode, the atmosphere control module opens the first control valve 14 and the second control valve 15 and adjusts the opening degree to make the protective gas form a continuous flow in the stamping chamber, so as to carry away the volatiles from the stamping chamber. In this embodiment, an intelligent atmosphere control strategy is formed, which ensures the process effect through two modes: gas washing and dynamic flushing. Among them, the gas washing mode can more thoroughly replace the air in the stamping chamber through multiple cycles of evacuation and filling with protective gas. The first evacuation and filling with protective gas can remove most of the air impurities, and the second and subsequent cycles can further remove residual air and contaminants, ensuring that a pure protective gas atmosphere is formed in the chamber, providing a good environment for the subsequent heating and stamping process. In dynamic flushing mode, by opening the first control valve 14 and the second control valve 15 and adjusting their opening, the protective gas forms a continuous flow in the stamping chamber. After stamping, when the workpiece is heated to the second preset temperature, the lubricating oil, water vapor, hydrocarbons and other contaminants volatilized on the workpiece surface can be promptly carried away from the stamping chamber by the continuously flowing protective gas, preventing these volatiles from accumulating in the chamber and re-adhering to the workpiece surface. This enhances the degassing and deoiling effect, making the workpiece surface cleaner and reducing contamination of the subsequent annealing furnace.

[0058] In a preferred embodiment, such as Figure 1As shown, the atmosphere control module includes a vacuum pump 21, a protective gas source 22, a vacuum pumping line 23, and an inlet line 24. The vacuum pump 21 is connected to the pressurization chamber through the vacuum pumping line 23, and the protective gas source 22 is connected to the pressurization chamber through the inlet line 24. The first control valve 14 is connected to the fluid path of the vacuum line, and the second control valve 15 is connected to the fluid path of the inlet line 24. The atmosphere control module has a simple overall structure and clearly defined functions for each component. The vacuum pump 21 can effectively evacuate the pressurization chamber through the vacuum pumping line 23, and the protective gas source 22 can stably fill the chamber with protective gas through the inlet line 24. The first control valve 14 is connected to the fluid path of the vacuum pipeline, enabling precise control of the vacuuming process and degree. The second control valve 15 is connected to the fluid path of the inlet pipeline 24, accurately adjusting the amount and rate of protective gas injection. Together, they allow the atmosphere control module to stably switch between the gas washing mode and the dynamic flushing mode, ensuring the accuracy and reliability of the atmosphere control within the chamber and guaranteeing the degassing, oil removal, and anti-oxidation effects. Specifically, the first control valve 14 can be an electromagnetic vacuum baffle valve, a pneumatic vacuum butterfly valve, etc., and the second control valve 15 can be an electromagnetic proportional valve, a pneumatic diaphragm regulating valve, etc. The preferred combination of the first control valve 14 and the second control valve 15 is an electromagnetic vacuum baffle valve and an electromagnetic proportional valve. The former meets the requirements for rapid vacuum switching and sealing, while the latter achieves precise flow control of the protective gas. Both can be linked through the system's electrical signals to adapt to the automation requirements of the gas washing mode and the dynamic flushing mode.

[0059] Regarding the heating system, as a preferred embodiment of the present invention, such as Figure 1 and Figure 2 As shown, the heating system includes a heating element embedded in the lower mold base 11. The heating element is a heating tube 25 arranged around the die cavity 13, allowing the heat generated by the heating tube 25 to be evenly transferred from the lower mold base 11 to the die cavity 13, and then from the die cavity 13 to the workpiece placed on it. This ensures uniform heating of the workpiece and avoids localized overheating or underheating of the workpiece. The heating tube 25 is embedded in the lower mold base 11, reducing heat loss to the external environment, improving heating efficiency, and protecting the heating tube 25 from external impacts and other damage, thus extending its service life. The heating tube 25 arranged around the die cavity 13 can concentrate the heating of the die cavity 13 and the workpiece, enabling the workpiece to quickly reach the first and second preset temperatures, shortening the heating time and improving production efficiency. Specifically, the heating tube 25 can be a resistance heating tube with a U-shaped or annular structure. The heating power is adjustable, which can accurately match the requirements of the first and second preset temperatures. It has a wide operating temperature range, good stability, and a corrosion-resistant metal shell, making it suitable for protective gas environments.

[0060] Furthermore, such as Figure 1 and Figure 2As shown, the lower die base 11 is also provided with a heat-conducting ring 26 and a heat-insulating structure 27. The heat-conducting ring 26 is sleeved around the outer periphery of the die cavity 13, and the heating tube 25 surrounds and contacts the outer periphery of the heat-conducting ring 26. The heat-insulating structure 27 is located on the side of the heating tube 25 away from the die cavity 13, which further optimizes the thermal management performance of the heating system. The heat-conducting ring 26 is tightly sleeved around the die cavity 13, which increases the heat conduction contact area between the heating tube 25 and the die cavity 13, and can quickly and evenly transfer heat to the die cavity 13, eliminating the risk of local overheating or overcooling, and making the workpiece heatd more quickly and evenly. The heat-insulating structure 27 located on the side of the heating tube 25 away from the die cavity 13 can effectively block the heat from being transferred to the body of the lower die base 11 and other parts such as the press worktable. Almost all of the heat is conducted to the die cavity 13 and the workpiece through the heat-conducting ring 26, which reduces energy waste, lowers equipment operating costs, and prevents heat conduction from causing thermal damage or thermal interference to other precision components of the equipment. In a preferred embodiment, the heat-conducting ring 26 can be made of copper alloy, aluminum alloy, high thermal conductivity graphite material, etc., and the heat insulation structure 27 can be made of ceramic fiber board, aerogel felt, rock wool board, etc.

[0061] The present invention provides a precision stamping method for heat spreaders, which employs the precision stamping device for heat spreaders with in-situ degassing and degreasing functions as described above, and includes the following steps:

[0062] The sealed chamber module establishes a partially sealed stamping chamber at the mold closing station of the punch 12 and the die 13, providing a relatively independent and stable spatial environment for subsequent atmosphere control and heating operations, avoiding interference from external air and impurities to the internal process; specifically, after the workpiece to be stamped is transported to the stamping station between the punch 12 and the die 13 through the material conveying channel by the external conveying structure, the lifting sealing ring 19 is driven to move upward, so that the sealing element 191 is pressed against the annular platform 181, and then together with the annular platform 181 and the flexible sealing body 20, they form a stamping chamber;

[0063] The atmosphere control module enters the gas washing mode: it performs multiple vacuuming and protective gas filling operations on the stamping chamber to replace the gas in the stamping chamber with protective gas, and removes as much of the air originally contained in the chamber as possible, including oxygen, water vapor and other impurities that may affect the quality of the workpiece; specifically, the first control valve 14 and the second control valve 15 are opened alternately, the vacuum pump 21 is given priority to vacuum, and then the protective gas source 22 delivers protective gas, and the cycle is performed at least twice.

[0064] Before stamping, the die 13 and the workpiece in the stamping chamber are heated to a first preset temperature. Specifically, since the heat spreader is mostly made of metal materials such as copper and aluminum, the heating tube 25 can be energized and heated by the control system at a first preset power. The first preset temperature can be set to 80°C to 150°C. Within this temperature range, the yield strength of the heat spreader material decreases and the plasticity increases, achieving the goal of softening the material, but not to the extent that it melts or deforms excessively, thereby reducing the stamping force required during stamping, reducing the wear of the die, and extending the service life of the die.

[0065] Stamping is performed under protective gas and a first preset temperature, that is, the upper die holder 10 moves down to close the punch 12 and the die 13.

[0066] After stamping, the punch 12 and die 13 remain in the closed state. The die 13 and the formed workpiece in the stamping chamber are heated to a second preset temperature higher than the first preset temperature and held for a predetermined time. The high temperature promotes the rapid volatilization of these contaminants. Since the punch 12 and die 13 remain in the closed state, it is equivalent to heating in a relatively closed small space, which is more conducive to the heat being concentrated on the workpiece and improving the volatilization efficiency. The predetermined holding time is to ensure that the contaminants have enough time to fully volatilize. At the same time, with the protective gas atmosphere, the volatilized contaminants can be carried out of the stamping chamber with the flow of the protective gas, preventing them from re-adhering to the workpiece surface. This greatly reduces the total amount of contaminants entering the subsequent annealing furnace, reduces the cleaning burden and maintenance cost of the annealing furnace, and reduces the impact on the subsequent annealing quality. This provides a strong guarantee for the efficient and high-quality production of the entire heat spreader. Specifically, for common heat spreader materials such as aluminum alloy and copper alloy, the heating tube 25 can be energized and heated at a second preset power through the control system. The second preset temperature can be set from 250°C to 350°C. Below 250℃, the degreasing time becomes excessively long, making it unsuitable for efficient production cycles. Above 350℃, stringent requirements are placed on the system's heat resistance, sealing materials, insulation design, and energy consumption, resulting in undesirable outcomes. Within the 250℃ to 350℃ range, oil molecules can quickly acquire enough energy to overcome their adsorption forces with the metal surface, transforming from a liquid or surface-adsorbed state into a gaseous state and being carried away by the protective gas flow. If the heat spreader uses special materials, such as certain high-temperature alloys or novel composite materials that are extremely sensitive to temperature, or if a special formula or stamping lubricant with a significantly different boiling point range is used, then the aforementioned first and second preset temperature ranges may need to be adjusted appropriately based on the actual situation.

[0067] In this method, by establishing a sealed environment in situ at the stamping station, performing atmosphere replacement, and conducting staged heating and stamping, multiple dispersed processes such as stamping, cleaning, preheating, and degassing are integrated into a continuous and automated process. By establishing a sealed stamping chamber and replacing it with a protective gas through a gas washing mode, the influence of airborne pollutants is avoided; heating to a first preset temperature before stamping optimizes the stamping performance of the workpiece, and stamping under a protective gas atmosphere improves forming accuracy; heating to a second preset temperature after stamping and holding it at that temperature efficiently promotes the volatilization of surface adsorbates, reducing the pollutant load on the subsequent annealing furnace. The overall process balances stamping quality and decontamination efficiency, achieving a highly efficient, clean, and high-quality precision manufacturing process.

[0068] Furthermore, during the heat preservation stage after stamping, the atmosphere control module enters a dynamic flushing mode: the first control valve 14 and the second control valve 15 are opened and their openings are adjusted. The air intake flow rate of the second control valve 15 is greater than the air extraction flow rate of the first control valve 14. Simultaneously, vacuuming and protective gas filling are performed, creating a continuous flow of protective gas within the chamber. This allows volatiles generated on the formed workpiece to be discharged with the airflow, preventing them from circulating within the chamber and re-adhering to the workpiece surface. This further enhances the thoroughness of degassing and degreasing, providing a cleaner workpiece surface for subsequent annealing and indirectly improving annealing quality. In dynamic flushing mode, the first control valve 14 and the second control valve 15 can be adjusted to a slightly open state, establishing a continuous and slow directional airflow of protective gas. This facilitates precise control of the intake and extraction volumes, forming a low-speed, laminar protective gas flow field. This airflow can smoothly and evenly sweep across the workpiece surface, effectively carrying away the volatilized contaminant molecules. In addition, by precisely adjusting the air intake flow rate to be slightly greater than the air extraction flow rate, the pressure in the stamping chamber will be maintained at a slightly positive pressure. If there is any tiny leak in the stamping chamber, the gas will only leak from the inside to the outside, while the outside air cannot enter, thus ensuring the purity of the protective atmosphere during the dynamic rinsing process.

[0069] For any parts not mentioned in this invention, existing technologies can be used or referenced.

[0070] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments.

[0071] The above description is merely an 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 principle of the present invention should be included within the scope of the claims of the present invention.

Claims

1. A precision stamping device for heat-spreading sheets with in-situ degassing and degreasing functions, comprising an upper die holder, a lower die holder, and a driving mechanism for driving the upper die holder to close with the lower die holder, wherein the upper die holder is provided with a punch, and the lower die holder is provided with a die that cooperates with the punch, characterized in that, The precision stamping device for heat-spreading plates with in-situ degassing and oil removal functions also includes: A sealed chamber module is disposed between the upper mold base and the lower mold base, and is used to create a partially sealed stamping chamber at the mold closing position of the punch and the die; An atmosphere control module is connected to the stamping chamber and controls the evacuation of the stamping chamber through a first control valve and the filling of the stamping chamber with protective gas through a second control valve. A heating system for heating the die and / or workpiece located in the stamping chamber; A control system is used to control the operation of the drive mechanism, the sealed chamber module, the atmosphere control module, and the heating system; The heating system is controlled by the control system to perform a phased heating mode: before stamping, the workpiece is heated to a first preset temperature, and after stamping, the workpiece is heated to a second preset temperature higher than the first preset temperature and kept at that temperature. The sealed chamber module includes: A fixed platform is fixedly mounted on the lower die base and surrounds the die cavity. The fixed platform is provided with a material conveying channel for conveying workpieces to the stamping station between the punch and the die cavity by an external conveying structure. The fixed platform includes a ring-shaped platform at the top and multiple legs supporting the ring-shaped platform and the lower die base, with the material conveying channel formed between adjacent legs. A lifting sealing ring surrounds the concave mold and can be vertically lifted relative to the lower mold base; a sealing element is provided on the top of the lifting sealing ring. A flexible sealing body, the upper and lower ends of which are respectively sealed to the upper mold base and the fixed platform; The lifting sealing ring is raised under the control of the control system so that the sealing element at its top presses against the bottom surface of the fixed platform, thereby forming the stamping chamber together with the fixed platform and the flexible sealing body.

2. The precision stamping device for heat-spreading plates with in-situ degassing and deoiling functions according to claim 1, characterized in that, The flexible sealing body is a metal bellows. The top of the fixed platform is provided with a first flange face. The lower end of the metal bellows is detachably and sealed to the first flange face through a first transition connector. The bottom of the upper mold base is provided with a second flange face. The upper end of the metal bellows is detachably and sealed to the second flange face through a second transition connector.

3. The precision stamping device for heat-spreading plates with in-situ degassing and deoiling functions according to claim 1, characterized in that, The atmosphere control module is controlled by the control system and has a gas washing mode and a dynamic flushing mode: in the gas washing mode, the atmosphere control module performs the action of first evacuating and then filling with protective gas at least twice in a cycle; in the dynamic flushing mode, the atmosphere control module opens the first control valve and the second control valve and adjusts the opening degree so that the protective gas forms a continuous flow in the stamping chamber, so as to carry the volatiles away from the stamping chamber.

4. The precision stamping device for heat-spreading plates with in-situ degassing and degreasing functions according to claim 3, characterized in that, The atmosphere control module includes a vacuum pump, a protective gas source, a vacuum pumping line, and an air inlet line. The vacuum pump is connected to the stamping chamber through the vacuum pumping line, the protective gas source is connected to the stamping chamber through the air inlet line, the first control valve is connected to the fluid path of the vacuum pumping line, and the second control valve is connected to the fluid path of the air inlet line.

5. The precision stamping device for heat-spreading plates with in-situ degassing and deoiling functions according to claim 1, characterized in that, The heating system includes a heating element embedded in the lower mold base, and the heating element is a heating tube arranged around the concave mold.

6. The precision stamping device for heat-spreading plates with in-situ degassing and degreasing functions according to claim 5, characterized in that, The lower mold base is also provided with a heat-conducting ring and a heat-insulating structure. The heat-conducting ring is sleeved on the outer periphery of the die, the heating tube surrounds and contacts the outer periphery of the heat-conducting ring, and the heat-insulating structure is provided on the side of the heating tube away from the die.

7. A method for precision stamping of a heat spreader, characterized in that, The precision stamping device for heat-spreading sheets with in-situ degassing and degreasing functions as described in any one of claims 1 to 6, the precision stamping method for heat-spreading sheets includes the following steps: The sealed chamber module creates a partially sealed stamping chamber at the mold closing position of the punch and die; The atmosphere control module enters the gas washing mode: it performs multiple vacuuming and protective gas filling operations on the stamping chamber to replace the gas in the stamping chamber with protective gas. Before stamping, the die and workpiece in the stamping chamber are heated to the first preset temperature; Stamping is performed under protective gas and a first preset temperature condition; After stamping is completed, the punch and die remain in the closed state, and the die and the formed workpiece in the stamping chamber are heated to a second preset temperature higher than the first preset temperature and kept at that temperature for a predetermined time.

8. The precision stamping method for heat spreader plates according to claim 7, characterized in that, During the heat preservation stage after stamping, the atmosphere control module enters the dynamic flushing mode: the first control valve and the second control valve are opened and the opening is adjusted so that the air intake flow of the second control valve is greater than the air extraction flow of the first control valve. Simultaneously, the vacuuming action and the filling of protective gas are performed, so that the protective gas forms a continuous flow state in the chamber, and the volatiles generated on the molded workpiece are discharged with the airflow.

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