A coating device and control method for metal substrate

Abstract

The present application relates to a coating device and control method for metal substrates. The coating device includes a workbench provided on a mounting plane and a bracket connected thereto. The coating device is provided with a second cooling mechanism, which includes a trough provided on the mounting plane. The trough includes a first accommodating space filled with a coolant to contact the side of the metal substrate close to the workbench to control the second target cooling rate of the metal substrate away from the composite film side. A plurality of air knives arranged along a first direction are provided above the trough to form the first cooling mechanism. The air knife outlet is provided with a preset angle toward the composite film side to control the first target cooling rate of the composite film away from the metal substrate side. The temperature of the coolant is adjusted by a temperature controller. The two-way cooling structure in the coating device works synergistically to make the shrinkage rate of the composite film and the metal substrate consistent during the cooling process, thereby effectively reducing the residual stress at the bonding interface, avoiding defects such as warping and bubbling, and improving the coating quality and bonding strength.

Description

Technical Field

[0001] The present invention relates to a coating device, and in particular to a coating device for a metal substrate and a control method thereof. Background Art

[0002] As a composite material that combines the mechanical strength of a metal substrate with the decorative and protective properties of a composite film, laminated metal sheets are widely used in building curtain walls, household appliance housings, and automotive interior and exterior panels. This type of material is not only required to have good corrosion resistance, pollution resistance, and oxidation resistance, but also to have a certain aesthetic and surface processing adaptability. As the demand for high-quality laminated metal sheet products in downstream industries increases year by year, the market has set higher standards for their surface flatness, interlayer bonding strength, and durability. Therefore, how to achieve stable, efficient, and reliable lamination between the composite film and the metal substrate in a continuous industrial production process has become an important research direction in the current field of metal laminate processing.

[0003] Currently, the most common method for producing metal-clad laminates is a continuous hot-press lamination process. A typical production line includes a metal substrate heating unit, a glue coating unit, a composite film unwinding device, a lamination mechanism, and a cooling section. The process typically involves heating the metal substrate to a preset temperature (e.g., 140°C to 180°C). Adhesive is then applied to the surface to be laminated. Once the adhesive reaches the desired initial adhesion, a PET / PVC composite film is applied to the substrate surface using a pressure roller. This is then pressed to achieve initial bonding, followed by curing and setting in a natural cooling or liquid- or air-cooled environment.

[0004] However, although the above process can basically achieve the lamination operation, due to the large differences in physical properties such as thermal expansion coefficient, thermal conductivity, and thermal inertia between the PET / PVC composite film and the metal substrate, this type of laminated metal plate often produces large thermal response differences between different material layers during rapid cooling, causing uneven interface thermal stress, which in turn leads to residual stress at the bonding interface. Once the residual stress exceeds the buffering limit of the adhesive layer, quality defects such as film warping, bubble bulging, edge warping, and local delamination are likely to occur, seriously affecting the apparent performance and structural strength of the final product. Therefore, it is necessary to propose a laminating device and control method for metal substrates to solve the above problems. Summary of the Invention

[0005] The object of the present invention is to provide a coating device and control method for a metal substrate, which overcomes the defects of warping, bubbling, interface debonding, etc. of the composite film surface caused by the different thermal expansion coefficients and thermal conductivity between the PET / PVC composite film and the metal substrate during the cooling process.

[0006] The technical solution adopted by the present invention to solve the above-mentioned problem is: a coating device for metal substrates, which coats a composite film on the side of a moving metal substrate coated with an adhesive layer, comprising a workbench, a bracket, a second cooling mechanism and a first cooling mechanism. The workbench comprises a mounting plane; the bracket is connected to the workbench; the second cooling mechanism comprises a trough body and a temperature controller, wherein the trough body is arranged at the mounting plane, the trough body is open away from the workbench side, the trough body comprises a first accommodating space, a cooling liquid is introduced into the first accommodating space, a first inlet and a first outlet are respectively provided on the two oppositely facing inner walls of the first accommodating space for the metal substrate to pass through the first accommodating space, the first inlet and the first outlet are both located at the same target height, so that the liquid level of the cooling liquid in the first accommodating space is limited to the target height, so that the cooling liquid contacts the side of the metal substrate passing through the first accommodating space close to the workbench, so as to control the cooling rate of the metal substrate away from the composite film side. The cooling rate on the side of the metal substrate away from the composite film is defined as the second target cooling rate, and the direction from the first inlet to the first outlet is defined as the first direction; a temperature controller is connected to the first accommodating space to adjust the temperature of the coolant; a first cooling mechanism is connected to the bracket, and the first cooling mechanism includes a plurality of controlled air knives, each of which is arranged above the trough body, and each of the air knives is arranged in sequence along the first direction, the air outlet of the air knife is set toward the first inlet, and the angle between the air outlet of the air knife and the side of the metal substrate covered with the composite film passing through the first accommodating space is set to a preset angle to control the cooling rate of the composite film away from the metal substrate side, and the cooling rate of the composite film away from the metal substrate side is defined as the first target cooling rate. Wherein, the first target cooling rate and the second target cooling rate are configured so that after the metal substrate covered with the composite film passes through the first accommodating space, the residual stress at the bonding interface between the composite film and the metal substrate is within the target range.

[0007] Preferably, the second cooling mechanism further includes a plurality of partition components, the partition components are arranged in the first accommodating space, and the partition components are arranged in sequence along the first direction to divide the first accommodating space into a plurality of cooling slots; there are a plurality of temperature controllers, and each temperature controller is connected to each cooling slot in a one-to-one correspondence to control the temperature of the coolant in each cooling slot respectively, and the temperature of the coolant in each cooling slot decreases in sequence along the first direction. When the coating device is in working state, the metal substrate enters the first accommodating space from the first inlet and passes through each cooling slot in sequence until it leaves the first accommodating space from the first outlet, and in the process of passing through the first accommodating space, the side of the metal substrate close to the workbench contacts the coolant in each cooling slot in sequence.

[0008] Preferably, the second cooling mechanism also includes an overflow groove, which is arranged around the outer peripheral side of the groove body, and the overflow groove includes a second accommodating space, and the inner wall of the second accommodating space is open away from the workbench side to accommodate the coolant overflowing from the first inlet and / or the first outlet, a second inlet is provided on the inner wall of the second accommodating space opposite to the first inlet, a second outlet is provided on the inner wall of the second accommodating space opposite to the first outlet, and a drain port connected to the second accommodating space is provided on the inner wall of the overflow groove close to the mounting plane.

[0009] In particular, a control method for the above-mentioned laminating device includes:

[0010] Obtaining the ambient temperature, physical parameters of the metal substrate, physical parameters of the composite film, and physical parameters of the adhesive layer;

[0011] Determining an upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate based on the physical parameters of the composite film and the physical parameters of the adhesive layer;

[0012] determining an allowable range of the first target cooling rate and an allowable range of the second target cooling rate based on an upper limit of a difference between a cooling rate of the adhesive layer and a cooling rate of the composite film on the side close to the metal substrate, physical parameters of the metal substrate, physical parameters of the composite film, and physical parameters of the adhesive layer;

[0013] The operation of the first cooling mechanism is controlled according to the allowable range of the first target temperature drop rate, and the operation of the second cooling mechanism is controlled according to the allowable range of the second target temperature drop rate.

[0014] Preferably, determining the upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate based on the physical parameters of the composite film and the physical parameters of the adhesive layer comprises the following steps:

[0015] Determining the upper limit of the residual stress allowed at the bonding interface between the composite film and the bonding layer based on the physical parameters of the composite film and the physical parameters of the bonding layer;

[0016] The upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate is determined according to the upper limit of the residual stress, the physical parameters of the adhesive layer and the physical parameters of the composite film.

[0017] Preferably, determining the allowable range of the first target cooling rate and the allowable range of the second target cooling rate based on the upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate, the physical parameters of the metal substrate, the physical parameters of the composite film, and the physical parameters of the adhesive layer comprises the following steps:

[0018] Determining an allowable range of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate based on an upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate, physical parameters of the adhesive layer, and physical parameters of the composite film;

[0019] The allowable range of the cooling rate of the metal substrate close to the composite film is determined based on the allowable range of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate, the physical parameters of the metal substrate, and the combined effect of the metal substrate and the composite film on the cooling rate of the adhesive layer.

[0020] The allowable range of the second target cooling rate on the side of the metal substrate away from the composite membrane and the allowable range of the first target cooling rate on the side of the composite membrane away from the metal substrate are determined respectively based on the allowable range of the cooling rate on the side of the metal substrate close to the composite membrane, the physical parameters of the metal substrate and the physical parameters of the composite membrane.

[0021] The beneficial effects of the embodiments of the present invention are as follows:

[0022] 1. By adopting the technical means of providing a first cooling mechanism and a second cooling mechanism in the laminating device, a first target cooling rate on the side of the composite film away from the metal substrate and a second target cooling rate on the side of the metal substrate away from the composite film are controlled respectively. Furthermore, an array of wind knives with adjustable air outlet angles and a cooling liquid tank are provided, and the cooling liquid temperature is precisely adjusted by a temperature controller, thereby forming a bidirectional, independently adjustable cooling path. Furthermore, by matching the first target cooling rate with the second target cooling rate, the thermal contraction behavior of the composite film and the metal substrate during the cooling process is synchronized, ensuring that the residual stress at the bonding interface is controlled within the target range. Therefore, the problem of uneven thermal stress at the bonding interface caused by the inconsistent thermal expansion coefficient and thermal conductivity of the composite film and the metal substrate in the prior art is effectively solved, thereby significantly reducing the risk of bonding defects such as warping, blistering, edge lifting, and delamination caused by excessive residual stress at the interface after cooling. Furthermore, precise control of the thermal stress of the adhesive layer and stable maintenance of the interface morphology are achieved during the continuous laminating process, improving the surface flatness and bonding strength of the product, and ensuring the structural integrity and appearance quality of the metal-clad plate.

[0023] 2. Since the present application establishes a residual stress control model based on the thermal properties of the material by obtaining the ambient temperature, the physical parameters of the metal substrate, the physical parameters of the PET / PVC composite film, and the physical parameters of the adhesive layer, and further, based on the thermal expansion difference and the interface effective modulus between the PET / PVC composite film and the adhesive layer, the allowable upper limit of the residual stress at the bonding interface is derived, and the maximum allowable cooling rate difference between the adhesive layer and the side of the PET / PVC composite film close to the metal substrate is reversely calculated, and then combined with the upper limit of the cooling rate difference and the thermal coupling relationship between the three layers of materials, the allowable range of the first target cooling rate and the second target cooling rate are derived in turn. Finally, according to the allowable range, the operating status of the first cooling mechanism and the second cooling mechanism is accurately controlled to achieve thermal synchronous cooling of the PET / PVC composite film and the metal substrate. This effectively addresses the uneven cooling problem inherent in existing technologies, caused by the lack of a coordinated cooling rate mechanism based on material parameters. Specifically, it addresses the inability to quantify the permissible thermal stress range at the bonding interface and the inability to control the temperature drop differential between the PET / PVC composite film and the metal substrate. This significantly reduces the risk of lamination defects such as warping, blistering, and delamination caused by excessive residual stress at the interface. Furthermore, the integration of numerical modeling and feedback control of the cooling process ensures a matching thermal response between the metal substrate and the PET / PVC composite film during the cooling phase, significantly improving the stability and long-term reliability of the lamination interface. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 A schematic structural view of a coating device proposed in an embodiment of the present invention is shown.

[0025] Figure 2 A schematic cross-sectional view of a coating device according to an embodiment of the present invention is shown.

[0026] Figure 3 Shown Figure 2 Schematic enlarged view at A in the middle.

[0027] Figure 4 A flow chart of a control method for a coating device proposed in one embodiment of the present invention is shown.

[0028] Figure 5 Shown Figure 4 The flowchart shown is for determining the upper limit of the difference between the temperature drop rate of the adhesive layer and the temperature drop rate of the composite film close to the metal substrate in step S200 of the control method.

[0029] Figure 6 Shown Figure 5 The flowchart of determining the allowable range of the first target temperature drop rate and the allowable range of the second target temperature drop rate in step S300 of the control method shown is shown.

[0030] Among them: 10, workbench; 110, installation plane; 20, bracket; 30, second cooling mechanism; 310, trough body; 311, first accommodating space; 312, first inlet; 313, first outlet; 320, partition assembly; 321, partition plate; 322, elastic sealing member; 330, overflow trough; 331, second accommodating space; 332, second inlet; 333, second outlet; 334, drain port; 340, guide assembly; 341, first guide roller; 342, second guide roller; 40, first cooling mechanism; 410, wind knife; 411, air outlet. DETAILED DESCRIPTION

[0031] The following embodiments of the present invention are described in further detail with reference to the accompanying drawings and examples. The following examples are used to illustrate the present invention but are not intended to limit the scope of the present invention.

[0032] The production and processing flow of the laminated metal plate is roughly as follows: heating the metal plate as a whole (heating to between 140 and 180 degrees), applying glue, curing the glue to a preset state (initial solid state), and using a pressure roller to stick the composite film to the side of the metal substrate coated with glue.

[0033] However, during the production process of existing PET / PVC coated metal sheets, due to the different thermal expansion coefficients of different materials, the temperature drop rates of different materials vary greatly during the cooling process, resulting in large uneven shrinkage deformation between different material layers, and then generating thermal stress differences at the interface. This stress will be retained in the form of residual stress after the material is finally solidified. When this residual stress is too large, it will cause defects such as pits, warping, and bubbles in the PET / PVC composite film layer, which will seriously affect the apparent appearance and interlayer bonding strength of the coated metal sheet.

[0034] Figure 1 A schematic structural diagram of a coating device proposed in an embodiment of the present invention is shown. Figure 2 A schematic cross-sectional view of a coating device according to an embodiment of the present invention is shown.

[0035] To solve the above problem, please refer to Figures 1 to 2. In a preferred embodiment of the present application, a coating device for a metal substrate is proposed, and the product is a coated metal plate. The coated metal plate includes a metal substrate (metal sheet or metal coil), an adhesive layer and a PET / PVC composite film, and the PET / PVC composite film is coated on the side of the metal substrate coated with the adhesive layer. Among them, PET / PVC composite films are widely used in fields such as home appliances and automobiles, and can effectively improve the appearance and performance of products. The coating device can independently control the cooling rate of the PET / PVC composite film away from the metal substrate side and the metal substrate away from the PET / PVC composite film side during the cooling process after the metal substrate and the PET / PVC composite film are bonded, thereby coordinating the thermal shrinkage response of the metal substrate and the PET / PVC composite film, thereby reducing the interface residual stress and improving the bonding quality and stability.

[0036] The coating device for metal substrates includes a workbench 10, a bracket 20, a first cooling mechanism 40 and a second cooling mechanism 30. The workbench 10 includes a mounting plane 110; the bracket 20 is connected to the workbench 10; the second cooling mechanism 30 includes a tank 310 and a temperature controller, wherein the tank 310 is arranged at the mounting plane 110, and the tank 310 is open away from the workbench 10. The tank 310 includes a first accommodating space 311, and a cooling liquid is introduced into the first accommodating space 311. A first inlet 312 and a first outlet 313 are respectively provided on two opposite inner walls of the first accommodating space 311 for the metal substrate to pass through the first accommodating space 311. The first inlet 312 and the first outlet 313 are both located at the same target height, so that the liquid level of the cooling liquid in the first accommodating space 311 is limited to the target height, so that the cooling liquid contacts the side of the metal substrate passing through the first accommodating space 311 close to the workbench 10, so as to control the temperature of the metal substrate away from the composite film. The cooling rate of the side, the cooling rate of the metal substrate away from the composite film side is defined as the second target cooling rate, and the direction of the first inlet 312 pointing to the first outlet 313 is defined as the first direction; the temperature controller is connected to the first accommodating space 311 to adjust the temperature of the coolant; the first cooling mechanism 40 is connected to the bracket 20, and the first cooling mechanism 40 includes a plurality of controlled air knives 410, each of the air knives 410 is arranged above the trough body 310, and each of the air knives 410 is arranged in sequence along the first direction, and the air outlet 411 of the air knife 410 is arranged toward the first inlet 312, and the angle between the air outlet 411 of the air knife 410 and the side of the metal substrate covered with the composite film passing through the first accommodating space 311 is set to a preset angle to control the cooling rate of the composite film away from the metal substrate side, and the cooling rate of the composite film away from the metal substrate side is defined as the first target cooling rate. The first target cooling rate and the second target cooling rate are configured so that after the metal substrate covered with the composite film passes through the first accommodating space 311 , the residual stress at the interface between the composite film and the metal substrate is within a target range.

[0037] Specifically:

[0038] The workbench 10 is a structural bearing platform for fixedly installing the second cooling mechanism 30. The workbench 10 is provided with a mounting plane 110 for arranging the trough 310. The bracket 20 is fixedly connected to the workbench 10 to support the first cooling mechanism 40. The second cooling mechanism 30 includes a trough 310 and a temperature controller. The trough 310 is arranged at the mounting plane 110. Its structure is a trough 310 with one side open, that is, the trough 310 is open on the side away from the workbench 10, and a first accommodating space 311 for containing coolant is formed inside the trough 310. The two opposite sides of the inner wall of the first accommodating space 311 are respectively provided with a first inlet 312 and a first outlet 313, both of which are located at the same target height, which is the stable liquid level of the coolant. The first direction is from the first inlet 312 to the first outlet 313, which is also the length direction of the workbench 10.

[0039] The metal substrate moves horizontally in a first direction, entering the first accommodating space 311 through the first inlet 312. This allows the metal substrate, facing away from the composite membrane, to contact the surface of the coolant in the first accommodating space 311, thereby cooling the metal substrate. The metal substrate then exits the first accommodating space 311 through the first outlet 313, completing the continuous cooling process for the metal substrate. In this embodiment, by setting the coolant level at a target height, the immersion depth of the metal substrate in the coolant remains approximately consistent throughout its passage through the first accommodating space 311. This allows for precise control of the cooling rate on the side of the metal substrate facing away from the composite membrane, which is defined as the second target cooling rate.

[0040] The temperature controller, connected to the first accommodating space 311, regulates the circulating temperature of the coolant within the tank 310. This control method can employ PID closed-loop feedback control or be linked to a host computer system to adjust the coolant temperature according to a set temperature curve. In this embodiment, precise regulation of the coolant temperature allows the cooling rate on the side of the metal substrate away from the composite film to be controlled, thereby achieving the second target cooling rate.

[0041] The first cooling mechanism 40 is mounted on the bracket 20, specifically located above the tank 310. This cooling mechanism comprises a plurality of air knife units 410, arranged sequentially along a first direction (the length of the workbench 10), with their air outlets 411 oriented toward the first inlet 312. The angle between the air outlet 411 of each air knife 410 and the side of the metal substrate covered with the composite film passing through the first accommodating space 311 is set to a predetermined angle. This predetermined angle can be adjusted by adjusting the orientation of the air outlet 411 of the air knife 410, thereby controlling the cooling rate of the composite film on the side away from the metal substrate. This cooling rate is the first target cooling rate.

[0042] In actual operation, the coated metal substrate (with the composite film facing upward) is transported horizontally at a constant speed, enters from the first inlet 312 on one side of the tank body 310, passes through the first accommodating space 311 in the tank body 310, and directly contacts the coolant of the set temperature at the bottom of the metal substrate. At the same time, the top receives the cold air spray from the wind knife 410 system, and finally leaves from the first outlet 313. In this embodiment, the independent control of the cooling rate of the bottom of the metal substrate and the top of the composite film is achieved by separately regulating the temperature of the coolant and the air outlet parameters (wind speed, wind temperature, angle) of the wind knife 410. The reasonable matching of the above two cooling rates can achieve a high degree of synchronization in the thermal shrinkage behavior, significantly reduce the residual stress of the bonding interface, and thus improve the stability and reliability of the bonding interface during subsequent use.

[0043] The laminating device of this embodiment can be widely adapted to metal substrates and PET / PVC composite film materials of different thicknesses and materials, and is suitable for integrated application in automated continuous production lines. The device has strong adaptability to external operating environments and can operate stably in the range of room temperature to medium temperature.

[0044] In this embodiment, a bidirectional independent cooling structure consisting of a cooling liquid tank and an array of wind knives 410 is adopted in the coating device, and the cooling rates of the metal substrate and the composite film are respectively regulated so that their thermal shrinkage responses during the cooling process tend to be consistent, thereby effectively solving the problem of uneven interface residual stress caused by differences in thermal expansion performance in the prior art, and thus significantly reducing the risk of bonding defects such as warping, edge lifting, and bulging during the cooling process, thereby improving the surface flatness and bonding strength of the composite board, and ensuring the structural integrity and stability of the metal coated product.

[0045] It should be noted that, during the laminating process, the equipment and devices related to the heating, gluing and laminating processes are not mentioned in this application. Since these devices are existing equipment, there is no need to elaborate on them here.

[0046] See also Figure 2. In order to further improve the temperature control accuracy and thermal stress regulation ability of the metal substrate away from the composite film side during the cooling process, in some embodiments, the second cooling mechanism 30 also includes a plurality of partition components 320, and the partition components 320 are arranged in the first accommodating space 311, and are arranged in sequence along the conveying direction (first direction) of the metal substrate, thereby dividing the first accommodating space into a plurality of continuously arranged cooling grooves. The partition components 320 form a liquid partition between each cooling groove to ensure that the coolant in different cooling grooves does not mix or interfere in the physical space. In addition, the number of temperature controllers is also several, and each temperature controller is connected to each cooling groove one by one to control the temperature of the coolant in each cooling groove respectively, and the temperature of the coolant in each cooling groove decreases in sequence along the first direction. In which, when the coating device is in working state, the metal substrate enters the first accommodating space 311 from the first inlet 312, and passes through each of the cooling grooves in turn until it leaves the first accommodating space 311 from the first outlet 313, and in the process of passing through the first accommodating space 311, the side of the metal substrate close to the workbench 10 contacts the coolant in each of the cooling grooves in turn.

[0047] Specifically:

[0048] The cooling tanks are structurally independent and continuously connected in their arrangement. To achieve segmented temperature control, each cooling tank is connected to a temperature controller. Each temperature controller forms a one-to-one control relationship with its corresponding cooling tank, enabling independent regulation of the coolant temperature in each cooling tank. When the laminating device is in operation, the coolant temperature in each cooling tank decreases sequentially along the direction of motion of the metal substrate, thus establishing a decreasing temperature liquid cooling path.

[0049] During operation of the laminating device, after being heated, glued, and laminated with the composite film, the metal substrate enters the first accommodating space 311 through the first inlet 312 under the action of the conveyor device (winding and unwinding device). It then passes through each cooling tank at a constant speed. During this process, the metal substrate, on the side closest to the worktable 10, comes into contact with coolant at different temperatures in each cooling tank. As the coolant temperature gradually decreases along the first direction, the cooling rate of the metal substrate on the side farther from the composite film also gradually changes. This avoids the stress abrupt change caused by instantaneous temperature drop under single cooling conditions, facilitates a gradual transition in the material's shrinkage process, and improves the residual stress distribution in the bonded structure.

[0050] The partition assembly 320 can be made of materials such as stainless steel, corrosion-resistant alloy, polytetrafluoroethylene, etc., and has good strength, temperature resistance and resistance to coolant corrosion. Its height needs to match the depth of the tank body 310 to ensure that the liquid level of the coolant can fit the metal substrate away from the composite membrane side, but overflow and cross-tank phenomenon will not occur. Furthermore, in order to enhance the sealing performance, a mosaic structure or a sealing rubber ring is set between each partition assembly 320 and the side wall of the tank body 310 to prevent the coolant from flowing and interfering between different cooling tanks. The temperature controller can be selected from an electric heating temperature control module, a compressor refrigeration unit or a heat exchange circulation system, etc., and can be flexibly configured according to the production rhythm and material properties.

[0051] The separation component 320 is suitable for a high-performance composite film lamination process that requires gradual control of the temperature change of the metal substrate, and can achieve more detailed temperature reduction rhythm control without additionally increasing the path length of the metal substrate.

[0052] This embodiment utilizes multiple cooling troughs and multiple, independent temperature controllers within the first accommodating space 311, creating a multi-stage, gradual liquid cooling path for the metal substrate as it passes through the cooling section. This effectively addresses the thermal stress concentration problem caused by sudden changes in cooling rate in the prior art, thereby achieving a delamination-based release of residual stress and significantly suppressing lamination defects, thereby improving the surface quality and interlayer bonding reliability of the film-clad laminate product. This structure offers excellent versatility and scalability for adapting to diverse material systems and multiple product specifications, providing a highly stable and flexible industrial film-clad cooling control method.

[0053] See also Figure 3 . In order to further improve the stability of the cooling process and the separation and sealing effect, in one embodiment, the separation component 320 includes a separation plate 321 and an elastic seal 322, wherein the separation plate 321 is installed in the first accommodating space 311, and its extension direction is perpendicular to the first direction, thereby dividing the entire first accommodating space 311 into a plurality of independent cooling slot areas, and the elastic seal 322 is installed on the side of the separation plate 321 away from the workbench 10, and the height of the elastic seal 322 away from the workbench 10 is the target height, so that the elastic seal 322 fits with the side of the metal substrate close to the workbench 10 when the metal substrate passes through the first accommodating space 311.

[0054] Specifically:

[0055] The partition plate 321 can be made of a rigid material, such as stainless steel, engineering plastics, or a composite structure metal plate, to ensure good dimensional stability and corrosion resistance in a long-term immersion in coolant and temperature alternating environment.

[0056] To enhance the dynamic sealing effect between the partition plate 321 and the metal substrate and reduce the possibility of coolant flowing between adjacent cooling slots, an elastic seal 322 is installed on the side of each partition plate 321 away from the workbench 10. The elastic seal 322 extends closely against the upper edge of the partition plate 321 (the side of the partition plate 321 away from the workbench 10) to form a flexible, conformable structure. The top of the elastic seal 322 is at a target height, i.e., consistent with the coolant level. This ensures that when the metal substrate enters the first accommodating space 311 from the first inlet 312 and passes through each cooling slot in sequence, the side of the metal substrate closest to the workbench 10 forms a close, conformable contact with the corresponding elastic seal 322 as it passes through each cooling slot.

[0057] The elastic seal 322 can be made of an elastic material with excellent coolant corrosion resistance and wear resistance, such as EPDM, fluororubber, or silicone, to ensure both flexibility and long service life. The hardness and thickness of the contact surface can be adjusted appropriately based on the substrate material and surface roughness, ensuring a continuous and effective liquid seal without scratching the metal surface. In the contacted state, the elastic seal 322 deforms slightly when the substrate moves, ensuring a continuous seal during dynamic operation. Furthermore, the elastic seal 322 effectively prevents scratches on the bottom of the metal substrate during movement.

[0058] During operation, the coated metal substrate enters the first accommodating space 311 through the first inlet 312 and passes through each cooling slot in a predetermined direction. Because each cooling slot is physically separated by a partition plate 321 and sealed to the metal substrate at its top by an elastic seal 322, convection exchange and heat interference between the coolants in different cooling slots are effectively prevented. In this embodiment, a stepped temperature differential environment is created by the multiple independently separated cooling slot sections, allowing the metal substrate to undergo segmented temperature control within the cooling path, avoiding sudden stress changes caused by a single, drastic temperature drop.

[0059] The connection between the partition plate 321 and the tank body 310 can be a slide-in slot, welding or detachable screw connection, which is convenient for maintenance and cleaning. The seal can also be replaced regularly as a wearing part to ensure stable cooling performance.

[0060] In this embodiment, due to the technical means of adopting an elastic seal 322 arranged above the partition plate 321 and highly matched to the liquid surface of the coolant, the metal substrate always maintains a stable heat exchange interface with the coolant when passing through multiple cooling grooves, and avoids thermal disturbances between the coolants and liquid cross-groove phenomena, thereby effectively solving the problem of unstable cooling process caused by liquid cross-flow or uneven cooling in the prior art, and further realizing segmented and fine control of the cooling temperature of the bottom surface of the metal substrate, enhancing the stability and uniformity of the stress adjustment of the bonding interface, and improving the bonding quality and dimensional consistency of the finished plate.

[0061] See also Figures 1 to 2 . In order to further improve the stability of the cooling process and the liquid level control capability, in some embodiments, the second cooling mechanism 30 further includes an overflow trough 330, which is arranged around the outer peripheral side of the tank body 310 and has a frame-shaped surrounding structure as a whole. The overflow trough 330 includes a second accommodating space 331, and the inner wall of the second accommodating space 331 is open away from the workbench 10 to accommodate the coolant overflowing from the first inlet 312 and / or the first outlet 313, so as to form a closed but open liquid collection zone between the tank body 310. A second inlet 332 is provided on the inner wall of the second accommodating space 331 opposite to the first inlet 312, a second outlet 333 is provided on the inner wall of the second accommodating space 331 opposite to the first outlet 313, and a drain port 334 communicating with the second accommodating space 331 is provided on the inner wall of the overflow trough 330 close to the mounting plane 110.

[0062] Specifically:

[0063] The overflow trough 330 is set upward with its top opening (away from the workbench 10 side), so that when the coolant level in the first accommodating space 311 exceeds the target height due to fluctuation, introduction or disturbance, the excess coolant can naturally flow into the overflow trough 330 along the direction of gravity, thereby preventing the coolant from overflowing the device boundary or flowing into the installation area, ensuring the safe operation of the equipment and the cleanliness of the environment.

[0064] The overflow trough 330 defines a second accommodating space 331 for collecting and temporarily storing coolant overflowing from the first accommodating space 311. The inner wall of the second accommodating space 331 is designed with a drain port 334 on the side facing the mounting plane 110, facilitating the discharge or recovery of coolant through the drainage system once it reaches a specified level.

[0065] In order to ensure the passability of the metal substrate, the inner wall of the second accommodating space 331 is provided with a second inlet 332 at a position opposite to the first inlet 312, and a second outlet 333 at a position opposite to the first outlet 313, so as to correspond to the positions of the metal substrate entering and exiting the first accommodating space 311, respectively. In this way, while ensuring that the metal substrate passes through the first accommodating space 311, the local overflow generated at both ends of the first accommodating space 311 can be guided into the second accommodating space.

[0066] The overflow tank 330 can be constructed from coolant-resistant stainless steel, aluminum alloy, or high-strength plastic. It can be connected to the tank body 310 via welding, flange sealing, or removable snap-on connections to accommodate varying maintenance requirements. The volume and opening width of the second accommodating space 331 are designed to match the coolant flow rate within the tank body 310, ensuring that even during high-speed production, any occasional liquid overflows can be quickly channeled and collected. The drain port 334 can be connected to an external coolant recovery system or waste liquid treatment unit, enabling closed-loop management of the system.

[0067] During operation, the metal substrate coated with the composite film passes through the tank 310 in a first direction, maintaining the coolant at a target level. If the coolant level rises slightly above the edge of the storage space due to disturbances, feed fluctuations, or coolant replenishment, the coolant flows into the overflow tank 330 through the first inlet 312 or first outlet 313 of the tank 310, preventing overflow and improving the automation and reliability of liquid level management.

[0068] In this embodiment, due to the use of technical means such as the surrounding overflow groove 330 and its accompanying second accommodating space 331, drain port 334, second inlet 332 and second outlet 333, the first accommodating space 311 forms an auxiliary structure with overflow buffering and drainage control capabilities during operation, thereby effectively solving the problems of coolant overflow and environmental pollution caused by liquid level fluctuations or disturbances in the prior art, and further realizing automatic adjustment of the coolant level, improvement of the cleanliness of the device and long-term stability of the cooling system operation.

[0069] To ensure that the bottom of the metal substrate (on the side closest to the workbench 10) remains in full contact with the coolant during its passage through the first accommodating space 311, thereby maintaining a predetermined heat transfer efficiency, in some embodiments, the second cooling mechanism 30 further includes a plurality of guide assemblies 340. The guide assemblies 340 are connected to the trough body 310 and disposed within the first accommodating space 311, arranged sequentially along the first direction. Each guide assembly 340 is typically arranged in a one-to-one correspondence with each partition assembly 320 disposed within the first accommodating space 311, thereby forming a consistent guide control structure within each cooling trough.

[0070] The guide assembly 340 includes a pair of guide units symmetrically arranged on either side of the corresponding partition plate 321. The guide units include a second guide roller 342 and two symmetrically arranged first guide rollers 341. The first guide rollers 341 are rotatably connected to the trough body 310. The axes of the first guide rollers 341 are parallel to the horizontal plane and perpendicular to the first direction. The two first guide rollers 341 are arranged in parallel, and the line connecting the midpoints of their axes is perpendicular to the horizontal plane. The height of the midpoints of the line is equal to the target height, and the distance between the two first guide rollers 341 is slightly greater than the thickness of the metal substrate. The second guide roller 342 is rotatably connected to the trough body 310 and arranged parallel to the first guide roller 341. The second guide roller 342 is located between the two first guide rollers 341 and between the first guide roller 341 and the partition plate 321. When the metal substrate passes through the first accommodating space 311 , the metal substrate passes between the pairs of the first guide rollers 341 in sequence, and the side of the metal substrate close to the workbench 10 abuts against the side of the second guide rollers 342 away from the workbench 10 in sequence.

[0071] Specifically:

[0072] The axial direction of the first guide roller 341 is perpendicular to the conveying direction (first direction) of the metal substrate and is arranged parallel to the mounting plane 110 of the workbench 10. The first guide roller 341 is rotatably connected to the trough body 310 via a bearing assembly. The two first guide rollers 341 are equidistant from each other, with the spacing slightly greater than the thickness of the metal substrate, thereby creating a stable guide gap to ensure that the metal substrate passes stably along the preset path during conveyance. The line connecting the midpoints of the axes of the two first guide rollers 341 is perpendicular to the mounting plane 110, and its height is set to the target height, that is, the same as the coolant level, to ensure that the bottom surface of the metal substrate (on the side closest to the workbench 10) is always below the coolant.

[0073] The second guide roller 342 is also rotatably connected to the trough body 310. Its axis is arranged parallel to the first guide roller 341, with the axis of the second guide roller 342 positioned at a height between the axes of the two first guide rollers 341. Furthermore, the second guide roller 342 is positioned adjacent to the corresponding partition plate 321. As the metal substrate enters the first accommodating space 311 through the first inlet 312 and passes through each cooling trough, it passes between each pair of first guide rollers 341, with the side of the metal substrate closest to the worktable 10 always abutting against the outer surface of the second guide roller 342, which is located away from the worktable 10. This three-point support structure achieves effective positioning and guidance. In this embodiment, the positioning of the first and second guide rollers 341 and 342 ensures that the side of the metal substrate closest to the worktable 10 always maintains contact with the side of the second guide roller 342, which is located away from the worktable 10, during passage through the first accommodating space 311. This reduces the probability of the bottom of the metal substrate contacting the elastic seal 322, further tensions the metal substrate, and ensures that the bottom of the metal substrate is in constant contact with the coolant, ensuring cooling efficiency.

[0074] The first and second guide rollers 341, 342 can be made of stainless steel or corrosion-resistant engineering plastics, depending on the conveying load. They can be coated with a scratch-resistant coating to prevent scratches on the metal substrate. They are connected using removable bearing seats for easy maintenance and replacement. The layout density and roller diameter of the guide assembly 340 are matched to the length of the cooling trough to ensure that the guide assembly 340 does not deviate or tilt during conveyance.

[0075] In this embodiment, a guide assembly 340 consisting of a pair of guide rollers arranged in sequence along the conveying direction and an auxiliary guide roller arranged in the center is adopted, and combined with the cooling trough body 310, so that the metal substrate maintains sufficient contact with the coolant during the process of passing through the first accommodating space 311, thereby effectively solving the poor contact problem caused by thin materials, structural warping or liquid level fluctuations in the prior art, and further achieving the stability of heat transfer during the cooling process, the consistency of the cooling rate and the reliability of the interface residual stress control, thereby greatly improving the bonding quality and appearance flatness of the laminate.

[0076] To further enhance the stability and linear conveyance of the metal substrate during the cooling process, in some embodiments, the laminating device further comprises two tensioning mechanisms (not shown), which are respectively disposed on the first inlet 312 and the first outlet 313. When the laminating device is in operation, the metal substrate enters the first inlet 312 via the tensioning mechanism on the first inlet 312 side, passes through the first accommodating space 311, exits the trough 310 through the first outlet 313, and then passes through the tensioning mechanism on the first outlet 313 side. This ensures that the metal substrate in the first accommodating space 311 remains in a tensioned state.

[0077] Specifically:

[0078] The tensioning mechanism located on the first inlet 312 side is positioned before the metal substrate enters the first accommodating space 311. It can be a mechanical or pneumatic guide wheel assembly, an active tensioning wheel, or an electric servo tensioning roller. This tensioning mechanism is used to apply front-end traction to stably guide the metal substrate into the cooling trough 310 and ensure that its lower surface (near the workbench 10) is in full contact with the coolant level. The tensioning mechanism located on the first outlet 313 side is positioned after the metal substrate exits the first accommodating space 311. Its structure may include a pressure roller with automatic tension adjustment, a synchronous belt mechanism, or an electric winding unit to provide continuous back tension to ensure that the metal substrate maintains a linear extension state throughout its passage through the trough 310.

[0079] The two tensioning mechanisms work together to pull the metal substrate through the first inlet 312 and first outlet 313, respectively, effectively eliminating nonlinear motion caused by the metal substrate's own weight, vibration, warping, or fluid flow disturbances within the tank. This tensioning configuration not only helps maintain the metal substrate's trajectory (height-wise) within the first accommodating space 311 but also enhances its contact stability with the coolant during the cooling process, preventing uneven cooling or cooling path deviation caused by material fluctuation or curling.

[0080] In order to adapt to metal substrates of different thicknesses, widths and materials, different clamping forces and drive modes can be set for the two tensioning mechanisms. In addition, the stress state of the metal substrate during operation can be adjusted and controlled in real time by configuring a tension sensor and a closed-loop feedback mechanism, thereby improving the stability and adaptability of the system.

[0081] In this embodiment, due to the technical means of arranging tensioning mechanisms on the first inlet 312 side and the first outlet 313 side of the trough body 310, a longitudinal tensioning constraint can be formed when the metal substrate passes through the cooling trough body 310, thereby effectively solving the problem of unstable bottom height of the metal substrate caused by fluctuation or position drift of the metal substrate in the prior art, thereby achieving precise position control and consistent cooling effect during the cooling process, and improving the overall coating quality and controllability of the bonding interface stress.

[0082] In order to accurately control the cooling rate of the composite film away from the metal substrate side to meet the cooling rate requirements of composite films of different thicknesses and different materials, in some embodiments, the wind knife 410 structure in the first cooling mechanism 40 is further optimized and designed as a linear air outlet structure, and the linear air outlet 411 is parallel to the installation plane 110 and perpendicular to the first direction, so that when the metal substrate moves along the first direction, stable and uniform cold air coverage of the composite film surface is achieved. To make the air outlet angle adjustable to suit different layout requirements, the first cooling mechanism 40 further includes a first adjustment component (not shown) and an air source (not shown). The first adjustment component is disposed on the bracket 20, and the air knife 410 is connected to the bracket 20 via the first adjustment component. The first adjustment component is configured for controlled rotation, thereby driving the air knife 410 to adjust its angle, causing the air outlet direction of the air knife 410 to rotate about its mounting axis to change the angle between the air outlet 411 of the air knife 410 and the side of the metal substrate coated with the composite film passing through the first accommodating space 311. This forms cooling airflows at different angles with the side of the metal substrate coated with the composite film, allowing the cooling airflow to more closely adhere to the surface of the composite film, thereby effectively controlling the cooling rate and uniformity of the composite film layer. The air source operates in a controlled manner and is connected to the air knife 410.

[0083] Specifically:

[0084] The air source provides high-pressure airflow as a cooling air source. This air source may include a blower, air compressor, etc., and can be connected to a temperature control system (not shown in the figure) to further adjust the outlet air temperature, thereby achieving dual adjustment of the cooling air flow temperature and wind speed.

[0085] Multiple air knives 410 are arranged sequentially along a first direction and set to appropriate air outlet angles and directions by a first adjustment component, so that their cool air jets form an angle-adjustable air curtain structure. This structure not only ensures air cooling intensity while covering the film surface, but also allows for rapid switching of air direction based on operating conditions, accommodating the cooling requirements of different film materials and lamination processes.

[0086] In this embodiment, the wind knife 410 with a linear air outlet 411 structure is used in conjunction with an adjustable first adjustment component and a controlled air source, thereby effectively solving the technical problems in the prior art such as fixed cooling airflow direction, poor adaptability, and uneven cooling that lead to warping of the bonding interface or excessive residual stress, thereby achieving precise control of the cooling rate of the composite film surface and improving the uniformity of the cooling process, enhancing the stability of the bonding interface morphology, and significantly improving the quality and consistency of the finished coated product.

[0087] It should be noted that the traditional metal lamination production line adopts a continuous hot-pressing lamination process. Although it can complete the lamination process, it has the following technical bottlenecks:

[0088] Differences in material properties lead to asynchronous thermal responses during the cooling process. PET / PVC composite films and metal substrates (such as steel and aluminum) exhibit fundamental differences in thermal expansion coefficient, thermal conductivity, and specific heat capacity. During rapid cooling, the composite film and substrate cool at different rates, leading to differential interfacial thermal stress.

[0089] Residual stress at the bonding interface is difficult to control. Cooling stages typically rely solely on air or liquid cooling, lacking independent cooling control mechanisms for different material layers. Once the residual stress caused by asynchronous thermal contraction exceeds the adhesive layer's buffering capacity, defects such as warping and bulging can occur.

[0090] In addition, the existing cooling equipment has a simple structure and does not consider the thermal stress relief mechanism of the composite structure in the cooling path after bonding. It is easy for stress concentration to occur in the initial or final section and lacks the ability of "stress layered release".

[0091] The technical solution proposed in this application addresses the stress problem caused by inconsistent thermal responses, and proposes innovations in two dimensions: device structure and cooling control logic:

[0092] At the structural improvement level:

[0093] First, a two-way independent cooling system is implemented. The first cooling mechanism 40 (air knife system 410) controls the cooling rate on the side of the composite film away from the substrate, while the second cooling mechanism 30 (cooling liquid tank system) controls the cooling rate on the side of the metal substrate away from the composite film. These two systems are physically independent, and their operating parameters can be controlled independently, fundamentally breaking away from the limitations of existing unified cooling structures.

[0094] Secondly, a gradient cooling structure with multiple segmented cooling troughs and temperature control units is set up. The first accommodating space 311 is divided into cooling troughs by multiple partition components 320. The temperature of each trough body 310 can be set individually, forming a liquid cooling channel that sequentially reduces the temperature along the movement direction of the metal substrate, realizing temperature difference distribution control, thereby "segmented stress release".

[0095] In addition, a guide assembly 340 and a tensioning mechanism are provided to provide stable substrate path control and a tensioning stress mechanism, thereby assisting in achieving geometric stability and cooling uniformity during the material cooling process.

[0096] At the same time, an overflow structure is set on the outside of the coolant tank to improve the system liquid level stability and operation safety.

[0097] At the control logic level:

[0098] This application controls the interfacial thermal stress by controlling the difference between the first target cooling rate (composite film side) and the second target cooling rate (metal substrate side) within an allowable range: based on the thermal stress formation mechanism, the cooling rate difference is limited to ensure that the residual stress is within the target range; and a rate control method for thermophysical property matching is proposed; and an adaptive control closed loop can be formed through sensors and feedback control or prediction models.

[0099] It should be emphasized that, under current circumstances, it is often difficult for those skilled in the art to directly conceive of the technical solutions proposed in this application. This is because, for metal substrates such as PET / PVC composite films, existing literature and patents do not clearly distinguish and treat the laminated composite structure as a double-sided cooling target. Most solutions focus on improving film uniformity (such as glue coating uniformity and heating temperature) rather than regulating interfacial stress during the subsequent cooling stage. Traditional cooling devices mostly control cold air / cold water in a unified manner and do not have a structural configuration that allows for separate control of the upper and lower layers.

[0100] Starting from the simplification of the model, this application proposes to use the target cooling rate difference as the core control indicator, which has engineering feasibility, rather than staying at the theoretical thermal stress simulation level. In addition, the system integration design is difficult and requires high structural coordination. To achieve the coordinated operation of independent air-cooling / liquid-cooling systems, it is necessary to take into account the spatial layout, structural stress matching, and control system stability, which far exceeds the complexity of the traditional simple natural air-cooling design. Among them, the cooling segmentation and temperature control zoning technology require the cross-border integration of liquid cooling technology and mechanical conveying control technology. The idea of ​​introducing cooling tank segmentation and independent temperature control in this application is a structural breakthrough in the traditional coating process, and is not a natural extension of the conventional thinking path in this field.

[0101] In summary, this application, starting from the fundamental physical reasons for the control of interfacial thermal stress, proposes for the first time to control the difference in shrinkage rates between the metal substrate and the composite film through a two-way independent cooling system. A three-dimensional cooling control system with segmented cooling troughs, dynamic liquid level control and adjustable cold air angle is creatively constructed. The technical means of this application are fundamentally different from the existing cooling section structure in configuration logic, control objectives and adaptability. It solves the problem of fitting defects that are difficult to avoid under traditional structures. It is a technical solution that is difficult for those skilled in the art to directly associate with before seeing the content of this application, and it has obvious creativity.

[0102] See also Figure 4Based on the above-mentioned laminating device, the present invention addresses the problem of thermal residual stress imbalance between the PET / PVC composite film and the metal substrate during the cooling process by proposing a stress coordination method based on separate control of target cooling rates. This control method uses the side of the composite film away from the metal substrate and the side of the metal substrate away from the composite film as independent cooling targets. The first cooling mechanism 40 and the second cooling mechanism 30 are used to regulate the cooling rates of the corresponding sides, ultimately achieving dynamic coordinated control of the bonding interface stress.

[0103] Specifically, this control method incorporates a residual stress model for the adhesive layer interface. Based on material physical parameters (including thermal expansion coefficient, thermal conductivity, specific heat capacity, thickness, and Young's modulus), it derives the upper limit of the permissible difference in cooling rate per unit time between the adhesive layer and the composite film. This upper limit is then used to reversely analyze the target cooling rate range for the metal substrate and composite film away from the interface. By constructing a coupled thermal diffusion expression, the cooling behavior of the non-directly coolable region is equivalently expressed as a function of the controllable side, establishing a control linkage between the cooling paths.

[0104] On this basis, the laminating device employs an adjustable air knife 410 as the first cooling mechanism 40, equipped with an angle adjustment component and an air source control module, enabling precise control of air speed, temperature, and air outlet direction. The second cooling mechanism 30 is a multi-segment liquid cooling tank 310, each equipped with a temperature control module, a liquid level adjustment mechanism, and a thermal sensor, enabling gradient cooling control along the feed direction. Specifically, infrared temperature sensors or thermocouples are used to collect real-time surface temperatures on each side, forming a cooling rate feedback loop. The main control device then implements PID control based on the target rate range, ensuring that the actual cooling process matches the stress safety range, thus preventing defects such as warping, blistering, and delamination at the interface.

[0105] This control method, by adopting a thermal response inverse mechanism with residual stress modeling as the core, combined with the cooling structure decoupling design and the multi-parameter adjustable air knife 410 / liquid cooling control module, can effectively solve the problem of interface stress imbalance caused by asynchronous cooling in the existing technology, thereby minimizing the interface stress and controlling the composite bonding defects during the cooling process, thereby significantly improving the interface stability and comprehensive bonding quality of the coated products.

[0106] Moreover, compared with the prior art, this control method has the following significant creative features and beneficial effects:

[0107] From a control logic perspective, this control method breaks through the limitations of traditional single-sided temperature control or overall cooling and temperature equalization modes. For the first time, the present invention treats the side of the composite film away from the metal substrate and the side of the metal substrate away from the composite film as independent cooling targets, proposes a dual-target cooling rate control strategy, and establishes a thermal coupling boundary constraint relationship centered on residual stress, achieving reverse analysis of the temperature path for stress control and extraction of adjustable targets. This approach differs from existing technologies that rely on empirical temperature settings or equivalent thermal balance control methods, and is more scientific and precise.

[0108] In terms of thermal control modeling, this method introduces the upper limit of interfacial residual stress as a core constraint. A stress response model is established using multiple physical parameters, such as thermal expansion differences, Young's modulus, and layer thickness ratios. Based on this, the maximum allowable range of the difference in cooling rate per unit time is derived. Furthermore, combining the thermal diffusion delay and interlayer thermal resistance of the multilayer structure, a complete temperature-stress-cooling path coupling chain is established, achieving a physical and logical closed loop from material parameters, temperature response, stress response, to target control value. This method is a calculable, controllable, and feasible method for active residual stress control.

[0109] In terms of structural implementation, this method utilizes an angle-adjustable air knife 410 mechanism and a multi-stage, zoned, temperature-controlled liquid cooling tank 310, each acting on the distal ends of the composite film and metal substrate. The cooling mechanism coordinates with the target rate range to achieve closed-loop control. The air knife 410 is equipped with an adjustable angle mechanism and air pressure and temperature control components, while the liquid cooling tank 310 incorporates a zoned PID temperature control module and liquid level management structure, creating a highly dynamic, dual-channel thermal control system that far surpasses traditional static cooling structures in terms of dynamic thermal shock response.

[0110] At the system execution level, this invention uses real-time temperature measurement (e.g., infrared sensors or thermocouple arrays) to provide feedback on the current cooling rate, and then implements closed-loop PID control based on the target rate range. This control method is not only dynamic and real-time, but also allows for real-time adjustment of cooling parameters based on varying operating conditions (e.g., material thickness variations, ambient temperature fluctuations), offering high adaptability and significantly improving its applicability and reliability in industrial settings.

[0111] In summary, the present invention not only realizes the independent control of bilateral collaborative cooling in the system structure, but also realizes the target rate derivation and dynamic adjustment based on residual stress modeling in the control method, which significantly improves the interface stress control ability of the composite bonding process, effectively avoids defects such as interface warping and peeling, and has obvious innovation and practical value.

[0112] The control method specifically includes the following steps:

[0113] Step S100: Obtaining the ambient temperature T e, physical parameters of the metal substrate, physical parameters of the PET / PVC composite film and physical parameters of the adhesive layer;

[0114] Step S200: Determining an upper limit of the difference between a cooling rate of the adhesive layer and a cooling rate of the PET / PVC composite film on the side close to the metal substrate based on the physical parameters of the PET / PVC composite film and the physical parameters of the adhesive layer;

[0115] Step S300: Determining an allowable range of the first target cooling rate and an allowable range of the second target cooling rate based on an upper limit of a difference between a cooling rate of the adhesive layer and a cooling rate of the PET / PVC composite film on the side close to the metal substrate, physical parameters of the metal substrate, physical parameters of the PET / PVC composite film, and physical parameters of the adhesive layer;

[0116] Step S400: controlling the operation of the first cooling mechanism 40 according to the allowable range of the first target temperature drop rate, and controlling the operation of the second cooling mechanism 30 according to the allowable range of the second target temperature drop rate.

[0117] It should be noted that, in this embodiment, the composite film is selected as a PET / PVC composite film.

[0118] Wherein, step S100 obtains the ambient temperature T e , the physical parameters of the metal substrate, the physical parameters of the PET / PVC composite film and the physical parameters of the adhesive layer are as follows:

[0119] Ambient temperature T e The real-time temperature of the outside air serves as the initial boundary condition for the cooling process of the laminating device. Its changes directly impact the natural convection heat transfer capacity of the metal substrate and composite film, thus affecting the actual cooling rate. Ambient temperature can be collected and recorded in real time within the device's working area using a thermistor or thermocouple; or by using an infrared temperature sensor for non-contact temperature measurement of the surrounding air. Alternatively, a manual input port can be provided within the system's user interface for the operator to enter the plant temperature or set a constant temperature.

[0120] The physical parameters of the metal substrate are the basic physical parameters used to analyze the thermal diffusion and thermal stress changes of the metal substrate during the cooling process. The physical parameters of the metal substrate include the thermal expansion coefficient α of the metal substrate m : Characterizes the linear expansion capacity caused by a unit temperature change. It is one of the key parameters for thermal stress caused by temperature gradient. Its unit is 1 / K. It can be found in material data sheets or standard material databases (such as MATWEB, ASM Handbooks). For specially customized materials, actual testing can be performed using a thermomechanical analyzer (TMA); the thermal conductivity of the metal substrate is λ m: Characterizes the thermal conductivity of a material under a unit temperature difference, affecting the temperature propagation speed. The unit is W / (m·K). It can be measured using a laser thermal conductivity meter or hot wire method equipment (such as HotDisk). For general metal materials (such as aluminum and steel), refer to ASTME1952 and ASTMC177 standards. The physical thickness of the metal substrate d m :The thickness of the metal plate directly determines the length of the heat conduction path and is an important basis for calculating the heat flux density. It is directly measured using precision measuring instruments such as micrometers and laser thickness gauges. For large quantities of standard plates, the values ​​given in the supplier's specifications can be used; the specific heat capacity of the metal substrate c m : The amount of heat required to increase the temperature of a unit mass of material by 1°C, reflecting the thermal inertia of the material. The unit is J / (kg·K). You can refer to the room-temperature specific heat capacity data provided in the material standard manual or database. For special steel grades or treated materials, it is recommended to use a differential scanning calorimeter (DSC) for actual measurement; the density of the metal substrate ρ m : That is, the mass of material per unit volume, which is involved in the calculation of thermal diffusivity. Consult the supplier's product data sheet or authoritative material manual. If there is no clear data, it can be calculated by weighing and measuring the volume; Elastic modulus Em of metal substrate: Characterizes the elastic modulus of the metal, that is, the stress corresponding to unit strain, the unit is GPa. When performing thermal-mechanical coupling calculations, it is used to estimate the stress response caused by temperature difference. You can query the standard data of metal materials (such as steel, aluminum, copper, etc.), or use compression tests or static load tensile tests to obtain it.

[0121] The physical parameters of PET / PVC composite film include the thermal expansion coefficient of PET / PVC composite film (composite direction) α f : Reflects the thermal expansion trend of the composite film, especially in the in-plane direction, which affects the fitting stress. The expansion coefficient of each layer can be obtained through TMA testing, and then the weighted average is used to obtain the overall value. If it is a standard commercial film, it can be provided by the supplier or consult the film material manual; PET / PVC composite film thermal conductivity λ f : Determines the cooling rate of the film layer and affects the difference in thermal response between it and the metal substrate. You can refer to literature databases such as PolymerHandbook, or use a laser thermal conductivity meter or infrared steady-state plate method for actual measurement; the thermal conductivity of PET / PVC composite film thickness d f :The overall thickness of the composite film determines its thermal inertia and the thermal resistance of the bonding interface, which can be directly obtained by a non-contact laser thickness measurement system or an ultrasonic thickness gauge. For multi-layer structures, the thickness of each layer can be measured using a layered dissection method combined with a scanning electron microscope (SEM). The interlayer thermal resistance R of the PET / PVC composite film is i: Reflects the ability of multilayer film materials to pass heat through, especially affecting the uniformity of temperature drop. The unit is m²·K / W. The actual measurement process of this parameter is relatively cumbersome and can be estimated based on empirical literature data (such as papers on composite processing technology). If experimental modeling is required, the steady-state method or inversion method can be used to fit and derive the overall thermal diffusivity; PET / PVC composite film specific heat capacity: It affects the temperature change rate of the composite film. The overall or single-layer specific heat of the composite film can be measured by DSC, or the average value in the literature can be used as a reference (such as PET is about 1.0J / g·K to 1.3J / g·K); PET / PVC composite film Young's modulus E f Information provided by suppliers or available through DMA.

[0122] The physical parameters of the adhesive layer include the thermal expansion coefficient α of the adhesive layer b : Determines the ability of the adhesive layer to change volume with temperature and is one of the main factors in the formation of interfacial stress. It can be obtained by testing the cured adhesive layer through TMA or referring to the public data of polymer adhesives with similar performance; the thermal conductivity of the adhesive layer λ b : Determines the efficiency of heat transfer from the composite film to the metal substrate. It is the key to matching the heat flux between the upper and lower structures. It can be measured using a hot wire method (such as a TPS probe) or by referring to the polymer thermal conductivity range provided by the supplier (commonly 0.1W / m·K to 0.5W / m·K). The physical thickness of the adhesive layer d b : The thickness of the adhesive layer, usually in the order of tens to hundreds of microns, affects the thermal resistance and mechanical buffering effect. It can be measured using a layered scanning microscope or laser confocal microscopy. It can be estimated on site by calculating the coating parameters and the shrinkage rate after curing. The specific heat capacity of the adhesive layer is used for fine modeling of thermal strain. It can be directly measured by DSC or approximated by using a reference value based on the polymer type. The Young's modulus E of the adhesive layer is b : The stress-strain relationship of the adhesive within the elastic range after curing, in MPa, determines the ability of the adhesive layer to buffer thermal deformation. It can be obtained by DMA (dynamic mechanical analyzer) at different temperature ranges. For standard adhesives, the room temperature modulus can also be obtained from the manufacturer's data sheet; the yield strength of the adhesive layer : Characterizes the stress limit at which the adhesive layer begins to produce irreversible deformation. The unit is MPa. It can be obtained through the adhesive instructions, third-party test reports, or experimental methods. When obtaining it through experimental methods, standard film specimens must be prepared for tensile testing (refer to ASTM D638 or ISO 527).

[0123] The upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate is obtained according to the ambient temperature, the physical parameters of the PET / PVC composite film and the physical parameters of the adhesive layer in step S200. Figure 5 , including the following steps:

[0124] Step S210: determining an upper limit of the allowable residual stress between the bonding interface of the PET / PVC composite film and the bonding layer according to the physical parameters of the metal substrate and the physical parameters of the bonding layer;

[0125] Step S220: determining an upper limit of the difference in cooling rate between the adhesive layer and the composite film according to the allowable upper limit of the residual stress, the physical parameters of the adhesive layer, and the physical parameters of the PET / PVC composite film.

[0126] Specifically:

[0127] Step S210 derives the maximum thermal residual stress allowed at the bonding interface during the cooling process in the composite structure. , exceeding this value may cause defects such as peeling, blistering, and warping. Step S210 includes:

[0128] Step S211: Determine the interface stress conduction relationship model.

[0129] The basic form of interface residual stress can refer to the approximate formula of thermal stress: This formula is derived from the standard thermal stress formula in engineering thermal stress analysis. It is used to predict the interface stress caused by the difference in thermal expansion between different material layers. It is widely used in the analysis of interface residual stress in multi-layer structures (such as PCBs, thin film coatings, and composite materials). , that is, the thermal expansion coefficient of the composite film Thermal expansion coefficient of the bonding layer The difference between is the temperature difference during the cooling process; is the effective modulus of the interface, Eeff=(E f ·t f +E b ·t b ) / (d f +d b Furthermore, since residual stress is an irreversible stress generated after curing and setting, it is necessary to consider the yield behavior of the bonding layer material.

[0130] Step S212: Calculate the effective modulus of the interface .

[0131] Eeff=(E f ·t f +E b ·t b ) / (d f +d b ), where E f 、E b are the Young's modulus of the composite film and the adhesive layer, d f d bis the respective thickness. The modulus of the adhesive layer can be measured using TMA / DMA or by referring to polymer literature data. The modulus of PET / PVC composite films is generally determined by the primary PET / PVC material. This formula is used to estimate the combined stiffness of the two-layer composite under thermal deformation at the interface. It is a thickness-weighted average expression of linear elastic superposition. In this scenario, the composite film and adhesive layer are in close contact, and the thermal deformation process affects each other. This is simplified to a one-dimensional tensile model, assuming synchronous deformation and no slip between the two layers.

[0132] S213: Set the interface failure stress limit.

[0133] Interface failure is often caused by shear stress or peeling stress, and a safety limit needs to be introduced to calculate the maximum residual stress. ,in, is the safety factor. It is recommended to take any value between 0.6 and 0.8, depending on the reliability level of the working condition. It can be used to control the long-term reliability of the interface. This formula is a safety limit treatment, which is a conventional redundancy strategy in engineering design. It uses the yield strength (or fracture strength) of the adhesive layer multiplied by the safety factor. , and obtain the allowable upper limit that the residual stress cannot exceed. If the residual stress exceeds this limit, defects such as interface delamination, bubbles or stress cracking may occur.

[0134] Step S220 uses the interfacial residual stress expression mentioned in step S211 to reversely infer the upper limit of the difference in the unit time cooling rate between the PET / PVC composite film and the adhesive layer (i.e., the ultimate tolerance value of the degree of cooling unevenness). Step S220 includes:

[0135] Step S221: transforming the interface residual stress expression into a cooling rate model.

[0136] According to the thermal strain and stress principle, we can get: , rewritten as a time derivative, focusing on the stress increment per unit time, we can get .

[0137] remember: is the cooling rate of the composite membrane, is the cooling rate of the bonding layer.

[0138] but:

[0139] .

[0140] when When, among them, The cooling process time is set to the upper limit of the residual stress. , we can get .

[0141] Step S222: Determine the actual cooling process time .

[0142] This is the temperature from the completion of bonding Reduce to preset temperature The average cooling period is In some cases it is equal to the ambient temperature, but in most cases it is generally higher than the ambient temperature. It can be estimated based on the production line speed and cooling section length, or provided by on-site temperature control records.

[0143] Step S223: Obtaining the upper limit of the cooling rate difference.

[0144] The data obtained in step S222 Substitute into step S221 In the formula, we can get , This is the maximum allowable difference in cooling rate between the composite film and the adhesive layer per unit time. If the actual cooling rate between the composite film and the adhesive layer exceeds this value, the bonding interface between the adhesive layer and the composite film is at risk of instability.

[0145] In step S300, the allowable range of the first target cooling rate and the allowable range of the second target cooling rate are obtained based on the upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the PET / PVC composite film near the metal substrate, the physical parameters of the metal substrate, the physical parameters of the PET / PVC composite film, and the physical parameters of the adhesive layer. Figure 6 , including the following steps:

[0146] Step S310: determining an allowable range for the difference between the cooling rate of the adhesive layer and the cooling rate of the PET / PVC composite film on the side closest to the metal substrate based on an upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the PET / PVC composite film on the side closest to the metal substrate, physical parameters of the adhesive layer, and physical parameters of the PET / PVC composite film;

[0147] Step S320: determining the allowable range of the cooling rate of the metal substrate near the PET / PVC composite film based on the allowable range of the cooling rate of the adhesive layer, the physical parameters of the metal substrate, the allowable range of the cooling rate of the PET / PVC composite film near the metal substrate, and the combined effect of the metal substrate and the PET / PVC composite film on the cooling rate of the adhesive layer;

[0148] Step S330: determining an allowable range of the second target cooling rate on the side of the metal substrate away from the PET / PVC composite film based on the allowable range of the cooling rate on the side of the metal substrate close to the composite film and the physical parameters of the metal substrate;

[0149] Step S340: determining the allowable range of the first target cooling rate on the side of the PET / PVC composite film away from the metal substrate based on the allowable range of the cooling rate on the side of the PET / PVC composite film close to the metal substrate and the physical parameters of the PET / PVC composite film.

[0150] in:

[0151] Step S310 may determine an allowable range of a difference between a cooling rate of the adhesive layer and a cooling rate of the PET / PVC composite film on the side close to the metal substrate.

[0152] This step uses the maximum allowable cooling rate difference per unit time between the near side of the composite film and the adhesive layer (from step S200) and the cooling rate of the near side of the metal substrate to infer the cooling synergy that satisfies the residual stress limit. The details are as follows:

[0153] Step S311 : Modeling the residual stress tolerance boundary (from step S200 ).

[0154] .

[0155] The residual thermal stress control requirement is derived from the thermal strain formula, which establishes the direct boundary of the temperature gradient's effect on stress control, providing a strict and verifiable limit standard for engineering control.

[0156] Step S312: establishing a temperature response model of the bonding layer.

[0157] .

[0158] in:

[0159] , , ;

[0160] is the thermal resistance between the composite film and the adhesive layer, is the thermal resistance between the metal substrate and the adhesive layer, and The thermal conductivity of the bonding layer λ can be approximated b It is understandable that if there is a need for detailed modeling, the effective interface thermal resistance can be obtained through steady-state heat flow testing combined with a heat flow meter.

[0161] Step 313: Substitute the expression into the residual stress tolerance formula.

[0162] .

[0163] Through this inequality, we construct and The coupling relationship range of the two should be within the residual stress safety range. It should be noted that it is impossible to obtain the The value of is determined by the cooling regulation and heat diffusion of the composite film away from the metal substrate side, and will be derived through step S340 described later.

[0164] Step S320 can further analyze and obtain an acceptable cooling rate of the metal substrate close to the composite film side based on the constraint relationship obtained in step S310. Scope. The specific steps are as follows:

[0165] Step S321: Inversely solve the residual stress relationship in S310 scope.

[0166] .

[0167] Step S322: The data derived from S310 is and Substitute into the formula in step S321 and inversely deduce .

[0168] Step S330 can be based on the cooling rate of the metal plate close to the membrane side obtained in step S320. , combined with the physical parameters of the metal substrate, the allowable range of the adjustable cooling rate of the metal substrate away from the composite film side (ie, the contact surface with the coolant in the tank body 310) is derived.

[0169] Step S331: The metal substrate is a thick layer of metal, and its heat diffusion direction is assumed to be a one-dimensional plane heat conduction model:

[0170] ,in, .

[0171] This formula is derived from a combination of the classic one-dimensional heat diffusion model (Fourier's law) and the semi-infinite body heat conduction approximation. The heat diffusion delay ε approximates the hysteresis of the near-surface temperature response in thick plate heat transfer systems. This formula can link the actual cooling behavior at the far end with the development of near-surface stresses. By introducing ε, it also enables modeling of the internal thermal response of layered structures.

[0172] in, is the thermal diffusion hysteresis of the metal substrate, and Δt represents the time it takes to drop from the bonding completion temperature to the preset target temperature. In essence, it is the length of the critical cooling stage during which the bonding interface experiences thermal stress development. Δt determines how long it will take for residual thermal stress to form, and is the time basis for the residual stress change rate (dσ / dt). Therefore, it directly affects the size of ΔRmax (the allowable temperature drop difference per unit time). The shorter Δt is, the greater the allowable temperature drop difference per unit time, and the higher the control requirements. Δt can be obtained through production line parameter estimation, on-site temperature measurement, or production process. The production line parameter estimation method is based on the cooling section length and conveying speed, and is suitable for continuous production lines. ,in, The physical length of the cooling section (unit: m), which can be obtained from the equipment design drawings or actual measurements. is the metal plate conveying speed (unit: m / s), which can be read by the conveying control system or measured by the speed measuring wheel; on-site temperature measurement is applicable to devices with temperature monitoring points, and Δt is obtained through the actual temperature-time data curve, and a starting temperature measuring point (or default bonding temperature) is set after the bonding point; an end temperature measuring point is set at the outlet of the cooling section, and an infrared thermometer, thermocouple or thermal imager is used to record the temperature change of the same plate point along the conveying direction. The temperature curve is converted into a time curve by combining position and speed, and Δt is the time interval from the bonding completion temperature to the preset target temperature. This scheme can dynamically reflect the change of cooling efficiency and the data is accurate; the production process determination method is applicable to sensorless conditions. If the laminating equipment process has been standardized, Δt can be directly set as an empirical value, which can be specifically determined through the equipment manual or historical process specifications, the cooling station rhythm set by the operator's experience, the average cooling time at a fixed combination temperature in the experimental record, etc.

[0173] Step S332: The reverse solution is: (the allowable range of the second target temperature drop rate) is used as the liquid cooling target range of the second cooling mechanism 30.

[0174] In step S340, under the premise of ensuring that the residual stress between the film side and the adhesive layer is controllable, the allowable range of the cooling rate of the composite film side away from the metal substrate is determined according to the obtained cooling rate range of the metal substrate side away from the composite film.

[0175] Step S341: Obtained from step S330:

[0176] .

[0177] Step S342 is obtained from the thermal coupling relationship:

[0178] ,constraint: .

[0179] Step S343 Substituting in, we get the final constraint:

[0180] .

[0181] in, is the thermal diffusion hysteresis of the metal substrate, .

[0182] Step S344 transforms the above inequality and solves it inversely The value range of (the allowable range of the first target cooling rate) is:

[0183] ;

[0184] ;

[0185] in:

[0186] ; ; .

[0187] In getting After reaching the allowable range, the first cooling mechanism 40 controls the air output intensity of the air knife 410 to achieve the adjustment target.

[0188] It should be noted that, in the embodiment, there are the following coupling paths:

[0189] First, the cooling rate of the bonding layer is determined by the side of the composite film close to the metal substrate and the side of the metal substrate close to the composite film: .

[0190] Secondly, the cooling rate of the composite film close to the metal substrate , is not affected by direct cooling, but is determined by the heat conduction through the composite film layer on the side of the composite film away from the metal substrate: .

[0191] The cooling rate of the metal substrate close to the composite film side , which is also not affected by direct cooling, but is determined by the heat conduction from the metal substrate away from the composite film side: .

[0192] in: , are the thermal diffusion hysteresis in the thickness direction of the film layer and the plate, respectively.

[0193] And, in step S340 It is actually a control variable, but its control must be subject to the following conditions:

[0194] .

[0195] but: ,and ,and .

[0196] therefore, Must be with Linkage design is required, otherwise the temperature drop near the membrane side will be out of the controlled range, causing the temperature drop of the bonding layer to exceed the limit and causing the residual stress to exceed the standard.

[0197] Step S400 can control the operation of the first cooling mechanism 40 according to the allowable range of the cooling rate of the composite film away from the metal substrate side (the allowable range of the first target cooling rate) obtained in step S300, and control the operation of the second cooling mechanism 30 according to the allowable range of the cooling rate of the metal substrate away from the composite film side (the allowable range of the second target cooling rate), so as to maintain thermal coordination in the cooling process on both sides of the coated metal plate and avoid excessive interface residual stress.

[0198] The first cooling mechanism 40 adjusts the parameters of the air knife 410 (wind speed / angle adjustment, wind pressure, wind temperature, wind angle) to keep the composite film away from the metal substrate at a first target cooling rate. The second cooling mechanism 30 adjusts the cooling liquid parameters (temperature, liquid level, flow rate, and temperature gradient distribution of the cooling liquid in each cooling tank) to move the metal substrate away from the composite film side at a second target cooling rate. Cooling. The specific control process is as follows:

[0199] The control method of the first cooling mechanism 40 (the air knife 410 system) is to control the actual cooling rate of the composite film away from the metal plate side. Always within its allowed range Within.

[0200] An infrared temperature sensor or thermocouple array can be arranged above the surface of the composite film away from the substrate to continuously collect the temperature of the composite film. , calculate the instantaneous cooling rate:

[0201] .

[0202] Then, compare the current And control target range: If :Insufficient cooling, need to increase wind speed; if : Cooling is too fast, so the wind speed needs to be reduced or the outlet air temperature needs to be increased.

[0203] When executing control actions, multiple parameters of the air knife 410 system are controlled to achieve feedback regulation, including:

[0204] Air pressure regulation, adjusting the air supply volume through the fan inverter;

[0205] Air temperature regulation: adjust the outlet air temperature through hot air / cold air mixing valve or air duct preheating device;

[0206] Angle adjustment of the wind knife 410 (if equipped with the first adjustment component), which adjusts the outlet angle of the wind knife 410 through the servo motor to change the range of the local flow field;

[0207] The wind knife 410 array is zonal regulated, and the wind speed in different areas can be subdivided and controlled to adapt to the dynamic temperature difference of the composite membrane.

[0208] During the above adjustment process, the controller (PLC or industrial PC) collects temperature signals in real time to form a closed-loop PID control system to keep the actual cooling rate stable within the set range.

[0209] The control method of the second cooling mechanism 30 (liquid cooling tank system) is to ensure that the cooling rate of the metal substrate away from the composite film side is Always within the allowed range Within.

[0210] A zoned temperature control structure has been established, with the tank body 310 divided into several cooling tanks. Each cooling tank is equipped with a thermostat (heating / cooling module) and a temperature sensor, forming an independent temperature control unit. The coolant temperature decreases gradually along the feed direction to control the cooling rate.

[0211] In addition, a thermocouple sensor must be placed near the liquid surface of each cooling tank to record the coolant temperature in each zone in real time. , combined with the transmission speed And the substrate inlet and outlet temperatures, derive the substrate cooling rate per unit time .

[0212] Comparison calculated With target interval: If : If the liquid temperature is too low, increase the inlet temperature; if : If the liquid temperature is too high, lower the set temperature or increase the flow rate.

[0213] When executing control actions, the following control methods are included:

[0214] Liquid temperature control adjustment, adjust the set temperature of each zone thermostat;

[0215] Liquid flow rate regulation, controlling the liquid circulation rate through a variable frequency pump to improve heat exchange efficiency;

[0216] Overflow channel management: maintains a stable coolant level to avoid fluctuations in liquid cooling intensity.

[0217] Moreover, during the above adjustment process, a partitioned PID control system can also be used, with each cooling tank independently feeding back the corrected temperature to coordinately achieve full-length cooling gradient control.

[0218] The above contents described in this specification are merely examples of the present invention. Those skilled in the art may make various modifications, additions, or substitutions to the described embodiments, without departing from the contents of this specification or exceeding the scope defined by the claims, and such modifications, additions, or substitutions may be made to the described embodiments. Such modifications, additions, or substitutions may be made by persons skilled in the art. Such modifications, additions, or substitutions may be made to the described embodiments without departing from the contents of this specification or exceeding the scope defined by the claims, and such modifications shall fall within the scope of protection of the present invention.

Claims

1. A coating device for a metal substrate, for coating a composite film on a side of a moving metal substrate coated with an adhesive layer, characterized in that: include: Workbench, including mounting surface; a bracket connected to the workbench; The second cooling mechanism comprises: a trough body, arranged at the mounting plane, the trough body being open away from the workbench side, the trough body comprising a first accommodating space, a cooling liquid flowing into the first accommodating space, a first inlet and a first outlet being respectively provided on two oppositely facing inner walls of the first accommodating space for the metal substrate to pass through the first accommodating space, the first inlet and the first outlet being located at the same target height, so that the liquid level of the cooling liquid in the first accommodating space is limited to the target height, so that the cooling liquid contacts the side of the metal substrate passing through the first accommodating space close to the workbench, so as to control the cooling rate of the metal substrate away from the composite film side, the cooling rate of the metal substrate away from the composite film side being defined as the second target cooling rate, and the direction in which the first inlet points to the first outlet being defined as the first direction; a plurality of partitioning components, wherein the partitioning components are disposed in the first accommodating space, and the partitioning components are sequentially arranged along the first direction to divide the first accommodating space into a plurality of cooling slots; a temperature controller, connected to the first accommodating space, to adjust the temperature of the coolant; there are a plurality of temperature controllers, each of which is connected to each of the cooling slots in a one-to-one correspondence to control the temperature of the coolant in each of the cooling slots, and the temperature of the coolant in each of the cooling slots decreases sequentially along the first direction; a first cooling mechanism connected to the bracket, the first cooling mechanism comprising a plurality of controlled air knives, each of the air knives being disposed above the trough body and arranged sequentially along the first direction, the air outlets of the air knives being disposed toward the first inlet, and an angle between the air outlets of the air knives and a side of the metal substrate covered with the composite film passing through the first accommodating space being set to a preset angle, so as to control a cooling rate of the composite film away from the metal substrate, the cooling rate of the composite film away from the metal substrate being defined as a first target cooling rate; In which, when the coating device is in working state, the metal substrate enters the first accommodating space from the first inlet and passes through each of the cooling grooves in sequence until it leaves the first accommodating space from the first outlet, and in the process of passing through the first accommodating space, the side of the metal substrate close to the workbench contacts the coolant in each of the cooling grooves in sequence, and the first target cooling rate and the second target cooling rate are configured so that after the metal substrate coated with the composite film passes through the first accommodating space, the residual stress at the bonding interface between the composite film and the metal substrate is within the target range.

2. The laminating device according to claim 1, characterized in that The partition assembly comprises: a partition plate, disposed in the first accommodating space to partition the first accommodating space; An elastic seal is arranged on the side of the partition plate away from the workbench, and the height of the elastic seal away from the workbench is the target height, so that the elastic seal fits with the side of the metal substrate close to the workbench when the metal substrate passes through the first accommodating space.

3. The coating device according to claim 1, wherein: The second cooling mechanism also includes an overflow groove, which is arranged around the outer peripheral side of the groove body. The overflow groove includes a second accommodating space, and the inner wall of the second accommodating space is open away from the workbench side to accommodate the coolant overflowing from the first inlet and / or the first outlet. A second inlet is provided on the inner wall of the second accommodating space opposite to the first inlet, a second outlet is provided on the inner wall of the second accommodating space opposite to the first outlet, and a drain port connected to the second accommodating space is provided on the inner wall of the overflow groove close to the mounting plane.

4. The laminating device according to claim 2, characterized in that: The second cooling mechanism further comprises: A plurality of guide assemblies, each of which is connected to the trough body and is disposed in the first accommodating space and arranged sequentially along the first direction. Each of the guide assemblies is disposed in one-to-one correspondence with each of the partition assemblies. The guide assemblies include paired guide units, which are symmetrically distributed on both sides of the corresponding partition plate. The guide units include: Two symmetrically arranged first guide rollers, the first guide rollers being rotatably connected to the trough body, the axes of the first guide rollers being parallel to the horizontal plane and perpendicular to the first direction, the two first guide rollers being arranged in parallel, and a line connecting the midpoints of the axes of the two first guide rollers being perpendicular to the horizontal plane, the height of the midpoint of the line being equal to the target height, and the spacing between the two first guide rollers being slightly greater than the thickness of the metal substrate; a second guide roller, rotatably connected to the trough body, the second guide roller being parallel to the first guide roller, the second guide roller being located between two of the first guide rollers, and the second guide roller being located between the first guide roller and the partition plate; When the metal substrate passes through the first accommodating space, the metal substrate passes between each pair of the first guide rollers in sequence, and the side of the metal substrate close to the workbench abuts against each second guide roller away from the workbench in sequence.

5. The coating device according to claim 4, characterized in that: Also includes: Two tensioning mechanisms, the two tensioning mechanisms being respectively arranged at the first inlet side and the first outlet side; Wherein, when the coating device is in working state, the metal substrate enters the first inlet through the tensioning mechanism on the first inlet side, passes through the first accommodating space, leaves the trough body through the first outlet, and then passes through the tensioning mechanism on the first outlet side, so that the metal substrate in the first accommodating space is always kept in a tensioned state.

6. The laminating device according to claim 4, characterized in that: The air outlet of the wind knife is a linear air outlet, and the linear air outlet is arranged parallel to the installation plane and perpendicular to the first direction; The first cooling mechanism further comprises: a first adjustment component, disposed on the bracket and connected to the air knife, the first adjustment component being configured to rotate in a controlled manner to adjust an angle between the air outlet of the air knife and the side of the metal substrate covered with the composite film passing through the first accommodating space; An air source operates in a controlled manner, wherein the air source is connected to the air knife.

7. A control method for the coating device according to claim 6, characterized in that: include: Obtaining the ambient temperature, physical parameters of the metal substrate, physical parameters of the composite film, and physical parameters of the adhesive layer; Determining an upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate based on the physical parameters of the composite film and the physical parameters of the adhesive layer; determining an allowable range of the first target cooling rate and an allowable range of the second target cooling rate based on an upper limit of a difference between a cooling rate of the adhesive layer and a cooling rate of the composite film on the side close to the metal substrate, physical parameters of the metal substrate, physical parameters of the composite film, and physical parameters of the adhesive layer; The operation of the first cooling mechanism is controlled according to the allowable range of the first target temperature drop rate, and the operation of the second cooling mechanism is controlled according to the allowable range of the second target temperature drop rate.

8. The control method according to claim 7, characterized in that: The method of determining the upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate according to the physical parameters of the composite film and the physical parameters of the adhesive layer comprises the following steps: Determining the upper limit of the residual stress allowed at the bonding interface between the composite film and the bonding layer based on the physical parameters of the composite film and the physical parameters of the bonding layer; The upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate is determined according to the upper limit of the residual stress, the physical parameters of the adhesive layer and the physical parameters of the composite film.

9. The control method according to claim 7, characterized in that: The method of determining the allowable range of the first target cooling rate and the allowable range of the second target cooling rate based on the upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate, the physical parameters of the metal substrate, the physical parameters of the composite film, and the physical parameters of the adhesive layer comprises the following steps: Determining an allowable range of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate based on an upper limit of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film on the side close to the metal substrate, physical parameters of the adhesive layer, and physical parameters of the composite film; The allowable range of the cooling rate of the metal substrate close to the composite film is determined based on the allowable range of the difference between the cooling rate of the adhesive layer and the cooling rate of the composite film close to the metal substrate, the physical parameters of the metal substrate, and the combined effect of the metal substrate and the composite film on the cooling rate of the adhesive layer. The allowable range of the second target cooling rate on the side of the metal substrate away from the composite membrane and the allowable range of the first target cooling rate on the side of the composite membrane away from the metal substrate are determined respectively based on the allowable range of the cooling rate on the side of the metal substrate close to the composite membrane, the physical parameters of the metal substrate and the physical parameters of the composite membrane.

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