Circuit board film pressing device with warping prevention function

Abstract

The application discloses a circuit board film pressing device with a warping prevention function, and relates to the technical field of circuit board film pressing. The film pressing device comprises an import preheating device, a magnetic flow film pressing device and a pressure relief discharging device. During operation, the circuit board is put into the feeding port of the import preheating device. After the dry film is peeled off and preheated by the import preheating device, the dry film is transported to the magnetic flow film pressing device together with the circuit board. After the circuit board enters the magnetic flow film pressing device, the PLC outputs a dynamic current to the magnetic flow film pressing device. The magnetic flow variable fluid in the magnetic flow film pressing device is affected by a magnetic field and becomes a semi-solid state to press and repair the warped part of the circuit board. The circuit board after film pressing enters the pressure relief discharging device. The pressure relief discharging device eliminates the residual rigid thermal stress of the circuit board and transports the circuit board to the discharging port for discharging. The application has the effect of preventing warping by pressing and repairing the warped part of the circuit board through the magnetic flow film pressing device.

Description

Technical Field

[0001] This invention relates to the field of circuit board lamination technology, specifically a circuit board lamination device with anti-warping function. Background Technology

[0002] As electronic products become thinner, lighter, faster, and more integrated, the manufacturing processes of printed circuit boards (PCBs), especially ultra-thin boards, flexible boards, and high-density rigid-flex boards, face extremely high requirements for dimensional stability. In the dry film lamination process, heat and pressure are needed to tightly adhere the dry film photoresist to the surface of the copper-clad laminate. However, in existing lamination processes, board warpage has become a core bottleneck restricting yield.

[0003] Traditional lamination equipment often employs rigid metal rollers or simple pneumatic rollers, which suffer from significant rigidity limitations. The rigid rollers and circuit board surface are in line-contact, resulting in hard pressing. When there are local thickness tolerances, slight undulations, or differences in thermal expansion and contraction of the substrate, localized stress concentration can easily occur, leading to dry film stretching, circuit lateral shift, and even irreversible warping of the circuit board substrate. Current anti-warping methods in the industry mostly use cold presses for physical leveling, which not only increases additional processes and manufacturing costs but also easily damages delicate circuitry. Furthermore, because the internal stress is not truly eliminated, it is prone to rebound during subsequent high-temperature processes. Therefore, the industry urgently needs an adaptive lamination device capable of dynamically eliminating internal stress. Summary of the Invention

[0004] The purpose of this invention is to provide a circuit board laminating device with anti-warping function to solve the problem of circuit board warping in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a circuit board laminating device with anti-warping function, comprising an inlet preheating device, a magnetorheological molding device, a pressure relief and discharge device, and a rack cabinet, wherein the inlet preheating device and the pressure relief and discharge device are both mounted on the rack cabinet, and the magnetorheological molding device comprises a movable magnetorheological pressure roller and a fixed magnetorheological pressure roller; The movable magnetorheological roller includes a stator shaft, an electromagnetic coil, a flexible sleeve, and a lifting component. The lifting component is mounted on a frame cabinet, and the stator shaft is mounted on the lifting component. An electromagnetic coil is axially arranged on the outer wall of the stator shaft. A sealing key is rotatably mounted on the stator shaft and connected to the flexible sleeve. The flexible sleeve has a double-layer composite structure; its inner side is a flexible rotating skeleton, and its outer side is covered with a thermally conductive silicone layer. A sealed annular cavity is formed between the stator shaft and the flexible sleeve, and this annular cavity is filled with magnetorheological fluid. The fixed magnetorheological roller is mounted on the frame cabinet. During operation, the circuit board to be processed is manually placed into the feed inlet of the preheating device. The preheating device then conveys the circuit board to the magnetohydrodynamic (MHD) molding device. Simultaneously, two sets of dry film rollers in the preheating device rotate, peeling and conveying the dry film. The dry film slides along the surface of the heating module on the preheating device, preheating and softening it before molding. Before the circuit board enters the MHD molding device, a detection element scans and detects the pressing gap and undulation profile of the circuit board. After the circuit board enters the MHD molding device, the moving magnetohydrodynamic (MHD) roller moves up and down according to the pressing gap detected by the detection element until it is adjusted to a suitable molding position. After the movable magnetorheological roller is positioned, the PLC outputs dynamic current to the electromagnetic coils inside both the movable and fixed magnetorheological rollers in real time, based on the undulating contour detected by the detection element. The stator shaft is a hollow shaft with a hollow channel inside for arranging the control lines of the electromagnetic coils. The movable and fixed magnetorheological rollers have the same internal structure. Under the influence of the magnetic field released by the energized electromagnetic coil, the magnetorheological fluid inside the annular cavity causes the nano-iron particles inside the magnetorheological fluid to arrange into iron chains, and the liquid immediately becomes a hard semi-solid. The flexible sleeve has strong internal support and can press down on the warped parts of the circuit board. After repair and lamination, the circuit board leaves the magnetofluid molding device and enters a pressure-relieving discharge device composed of small rollers arranged in an alternating pattern. The pressure-relieving discharge device allows the circuit board to move forward in an extremely small S-shaped wave trajectory. In this repeated up-and-down slight bending, the molecular chains of the dry film and substrate in a highly elastic state are continuously stretched and compressed. The residual rigid thermal stress is completely broken and released by this physical alternating yielding. While moving in a wave-like motion, the cooling components rapidly convect and cool the circuit board. The circuit board, whose stress has been cleared, is completely solidified and shaped. After processing, the pressure-relieving discharge device conveys the circuit board to the discharge port of the equipment to complete the unloading.

[0006] The lifting component includes a connecting plate, a drive source, a lead screw, and a moving block. The connecting plate is mounted on the rack and connected to the drive source. The output end of the drive source is connected to the lead screw, and the lead screw is threadedly connected to the moving block. The drive source is a drive motor. During operation, the moving magnetorheological roller detects the pressing gap using a detection element and needs to be adjusted to a suitable pressing position. When the drive source operates, its output shaft drives the lead screw to rotate. The moving block moves linearly along the axial direction of the lead screw, causing the entire moving magnetorheological roller to move up and down synchronously. This precisely adjusts the distance between the moving and fixed magnetorheological rollers to adapt to the pressing requirements of circuit boards of different thicknesses, ensuring that the initial setting of the pressing pressure is accurate.

[0007] The sealing key is equipped with a toothed ring, the moving block is equipped with a support plate, and the support plate is equipped with a second drive source. The output end of the second drive source is equipped with a gear, which meshes with the toothed ring. The second drive source is a drive motor. During the film pressing operation, the second drive source operates, and the output shaft of the second drive source drives the gear to rotate. Since the gear meshes with the toothed ring on the sealing key, the rotation of the gear drives the toothed ring to rotate synchronously, thereby driving the sealing key and the flexible sleeve connected to it to rotate around the axis of the stator shaft. When the moving magnetorheological roller and the fixed magnetorheological roller cooperate to press the circuit board, the flexible sleeve can rotate actively, cooperating with the conveying of the circuit board to achieve continuous and uniform rolling of the dry film on the surface of the circuit board, ensuring the stability of the film pressing process and the pressing quality.

[0008] It also includes a magnetic isolation ring, which is sleeved on the stator shaft and located between two electromagnetic coils. The electromagnetic coils are covered with magnetic pole shoes. During operation, a magnetic isolation ring is provided between every two coils to ensure that the magnetic field generated by each coil radiates only vertically outward, and the magnetic fields of adjacent sections do not interfere with each other, thus avoiding magnetic crosstalk. The magnetic pole shoes covering the outside of the electromagnetic coils ensure that the magnetic field will never leak and penetrate to the circuit board. This not only protects the electronic components of the circuit board, but also maximizes the magnetization efficiency of the magnetorheological fluid.

[0009] It also includes a detection element and a control system. The detection element and the electromagnetic coil are electrically connected to the control system. During operation, the detection element scans the circuit board before it enters the magnetorheological molding device in real time, accurately acquiring the pressing gap data and surface undulation profile information of the circuit board, and transmitting this data to the control system in real time. Based on the received pressing gap data, the control system sends control commands to the lifting component of the moving magnetorheological roller, driving it to move up and down, thereby quickly and accurately adjusting the initial distance between the moving magnetorheological roller and the fixed magnetorheological roller to ensure that the molding requirements of circuit boards of different thicknesses are met. Meanwhile, the control system analyzes and processes the circuit board undulation profile information fed back by the detection element through an internally preset algorithm, generating dynamic current control signals for each electromagnetic coil inside the moving magnetorheological roller and the fixed magnetorheological roller. This allows the magnetorheological fluid in the annular cavity to rapidly change its viscosity and hardness according to the undulations of different positions on the circuit board, thereby causing the flexible sleeve to produce elastic deformation that matches the contour of the circuit board. This enables precise and dynamic pressing and repair of warped parts on the circuit board, ensuring the flatness of the circuit board surface and the adhesion quality of the dry film after lamination.

[0010] The preheating device includes an inlet component and a preheating component. The inlet component includes a conveyor roller, a high-position reel, and a low-position reel, all of which are rotatably mounted on a rack cabinet. The preheating component is connected to the rack cabinet. During operation, the circuit board is manually placed onto the conveyor roller, which rotates to transport the circuit board toward the magnetofluidic molding device. Simultaneously, the dry film wound on the high-position reel and the low-position reel begin to unwind. After being peeled off from the high-position and low-position reels, the dry film slides along the surface of the heating module of the preheating component. The heating module inside the preheating component quickly heats the dry film to a preset softening temperature, giving it good plasticity and preparing it for subsequent tight bonding with the circuit board. This ensures that the dry film is in the optimal bonding state when it enters the magnetofluidic molding device.

[0011] The preheating component includes an arc-shaped waste heat plate and a temperature monitoring element, both of which are mounted on a rack cabinet. A heating element is located on the back of the arc-shaped waste heat plate. During operation, the heating element is energized and generates heat. The heat is evenly radiated onto the dry film through the arc-shaped surface of the arc-shaped waste heat plate, allowing the dry film to fully absorb heat during transport and achieve a smooth transition from room temperature to softening temperature. The temperature monitoring element monitors the surface temperature of the arc-shaped waste heat plate and the actual temperature of the dry film in real time, ensuring that the dry film is always heated to the set optimal softening range.

[0012] The pressure-relieving discharge device includes an adjusting roller group, a fixed roller group, and a cooling air duct. The adjusting roller group is slidably mounted on the frame cabinet, and the fixed roller group is fixedly mounted on the frame cabinet. A cooling air duct is provided between every two roller shafts of the adjusting and fixed roller groups. During operation, the circuit board after lamination first enters the conveying channel formed by the adjusting and fixed roller groups. The adjusting roller group can be adaptively slidably adjusted on the frame cabinet according to the thickness of the circuit board to ensure a suitable clamping gap with the fixed roller group. This ensures that the circuit board can be conveyed smoothly and that appropriate pressure is applied to assist in stress release. During the conveying process, due to the staggered arrangement of the adjusting and fixed roller groups, the conveying path of the circuit board naturally forms an extremely small S-shaped wave trajectory. When the circuit board moves forward along this wave-shaped trajectory... The molecular chains inside the dry film and circuit board substrate, which are in a highly elastic state, are subjected to alternating stretching and compression as the circuit board bends. This repeated micro-bending deformation effectively breaks, disperses, and releases the residual rigid thermal stress generated by high temperature and pressure during the lamination process. At the same time, the cooling air ducts set between every two rollers of the adjusting roller group and the fixed roller group start working, blowing temperature-controlled cooling airflow onto the upper and lower surfaces of the circuit board to quickly and evenly convectively cool the circuit board. After the residual stress is fully released, the circuit board quickly solidifies and sets under the cooling effect, thereby effectively preventing possible warping deformation in the future. Finally, the circuit board that has undergone stress release and cooling and setting is smoothly conveyed to the discharge port of the equipment, completing the unloading of the entire lamination process.

[0013] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention breaks through the limitations of traditional rigid or pneumatic pressure rollers by using a magnetorheological pressing device. The pressure roller assembly adopts an innovative coaxial nested layout of "stationary electromagnetic stator + rotating flexible sleeve + magnetorheological fluid". When encountering local thickness tolerance or undulations on the plate surface, the stiffness of the local magnetorheological fluid is instantly changed by adjusting the current of the electromagnetic coil. While perfectly ensuring the dry film filling rate, it avoids stress concentration and elongation deformation caused by rigid extrusion.

[0014] 2. The flexible sleeve of the present invention adopts a composite design of flexible rotating skeleton + thermally conductive silicone layer, which not only ensures that the outer shell can stably transmit the driving torque of the motor without torsion tearing when the laminator is conveying the circuit board, but also allows the outer shell to closely follow the stiffness change of the internal magnetorheological fluid in the radial direction to produce local micro deformation, thereby achieving adaptive coverage of the circuit board thickness tolerance, fundamentally eliminating the stress concentration and laminator warping problems caused by rigid pressure rollers. Attached Figure Description

[0015] Figure 1 This is an overall structural diagram of the present invention; Figure 2This is a structural diagram of the magnetohydrodynamic molding device of the present invention; Figure 3 For the present invention Figure 2 A magnified view of a portion of region A in the middle; Figure 4 This is a diagram showing the internal structure of the magnetohydrodynamic molding device of the present invention; Figure 5 This is a structural diagram of the movable magnetorheological roller of the present invention; Figure 6 This is a structural diagram of the fixed magnetorheological roller of the present invention; Figure 7 This is a half-sectional view of the fixed magnetorheological roller of the present invention; Figure 8 This is an overall isometric view of the present invention.

[0016] In the diagram: 1. Inlet preheating device; 11. Inlet component; 111. Conveyor roller; 112. High-position reel; 113. Low-position reel; 12. Preheating component; 121. Arc-shaped waste heat plate; 2. Magnetorheological pressing device; 21. Moving magnetorheological roller; 210. Lifting component; 2101. Connecting plate; 2102. Drive source; 2103. Lead screw; 2104. Moving block; 2105. Support plate; 2106. Drive source two; 2107. Gear; 211. Stator shaft; 212. Electromagnetic coil; 213. Flexible sleeve; 214. Sealing key; 2141. Gear ring; 216. Annular cavity; 217. Magnetic isolation ring; 22. Fixed magnetorheological roller; 3. Pressure relief discharge device; 31. Adjusting roller group; 32. Fixed roller group; 4. Frame cabinet. Detailed Implementation

[0017] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0018] Example: Figures 1-8As shown, the present invention provides a technical solution: a circuit board laminating device with anti-warping function, comprising an inlet preheating device 1 and a rack cabinet 4. The inlet preheating device 1 includes an inlet component 11 and a preheating component 12. The inlet component 11 includes a conveyor roller 111, a high-position roller 112, and a low-position roller 113. The conveyor roller 111, the high-position roller 112, and the low-position roller 113 are all rotatably mounted on the rack cabinet 4. The preheating component 12 is connected to the rack cabinet 4. During operation, the circuit board is manually placed onto the conveyor roller 111. 111 rotates to transport the circuit board toward the magnetofluid molding device 2. At the same time, the dry film wound on the high-position reel 112 and the low-position reel 113 begin to unwind. After the dry film is peeled off from the high-position reel 112 and the low-position reel 113, the dry film slides along the surface of the heating module of the preheating component 12. The heating module in the preheating component 12 quickly heats the dry film to the preset softening temperature, so that the dry film has good plasticity, which is ready for subsequent tight pressing with the circuit board, ensuring that the dry film is in the best pressing state when it enters the magnetofluid molding device 2.

[0019] The preheating component 12 includes an arc-shaped waste heat plate 121 and a temperature detection element. Both the arc-shaped waste heat plate 121 and the temperature detection element are mounted on the rack cabinet 4. A heating tube is provided on the back of the arc-shaped waste heat plate 121. During operation, the heating tube is energized and heats up. The heat is evenly radiated onto the dry film through the arc-shaped surface of the arc-shaped waste heat plate 121, so that the dry film can fully absorb heat during the transport process and achieve a smooth transition from room temperature to softening temperature. The temperature detection element monitors the surface temperature of the arc-shaped waste heat plate 121 and the actual temperature of the dry film in real time to ensure that the dry film is always heated to the set optimal softening range.

[0020] It also includes a magnetorheological molding device 2, which includes a movable magnetorheological roller 21 and a fixed magnetorheological roller 22. The movable magnetorheological roller 21 includes a stator shaft 211, an electromagnetic coil 212, a flexible sleeve 213, and a lifting component 210. The lifting component 210 is mounted on the rack cabinet 4, and the stator shaft 211 is mounted on the lifting component 210. An electromagnetic coil 212 is axially mounted on the outer wall of the stator shaft 211. A sealing key 214 is rotatably mounted on the stator shaft 211 and is connected to the flexible sleeve 213. The flexible sleeve 213 has a double-layer composite structure. The inner side of the flexible sleeve 213 is a flexible rotating skeleton, and the outer side of the flexible rotating skeleton is covered with a thermally conductive silicone layer. A closed annular cavity 216 is formed between the stator shaft 211 and the flexible sleeve 213. The annular cavity 216 is filled with magnetorheological fluid. The fixed magnetorheological roller 22 is mounted on the rack cabinet 4. During operation, when the circuit board enters the magnetic field... Before the magnetic flux molding device 2, the pressing gap and undulation profile of the circuit board are scanned and detected by the detection element. After the circuit board enters the magnetic flux molding device 2, the moving magnetic flux pressure roller 21 moves up and down according to the pressing gap detected by the detection element until it is adjusted to a suitable pressing position. After the moving magnetic flux pressure roller 21 is adjusted, according to the undulation profile detected by the detection element, the PLC outputs dynamic current to the electromagnetic coil 212 inside the moving magnetic flux pressure roller 21 and the fixed magnetic flux pressure roller 22 in real time. The hollow channel inside the stator shaft 211 is a hollow shaft used to arrange the control line of the electromagnetic coil 212. Under the influence of the magnetic field released by the electromagnetic coil 212, the magnetic flux fluid in the annular cavity 216 causes the nano-iron particles inside the magnetic flux fluid to arrange into iron chains, and the liquid immediately becomes a hard semi-solid. The flexible sleeve 213 has strong internal support and can press and repair the warped parts on the circuit board.

[0021] It also includes a detection element and a control system. The detection element and the electromagnetic coil 212 are electrically connected to the control system. When working, the detection element scans the circuit board before it enters the magnetorheological molding device 2 in real time, accurately obtains the pressing gap data and the surface undulation profile information of the circuit board, and transmits this data to the control system in real time. According to the received pressing gap data, the control system sends a control command to the lifting component 210 of the moving magnetorheological roller 21 to drive it to move up and down, thereby quickly and accurately adjusting the initial distance between the moving magnetorheological roller 21 and the fixed magnetorheological roller 22 to ensure that the pressing requirements of circuit boards of different thicknesses are met. Meanwhile, the control system analyzes and processes the circuit board undulation profile information fed back by the detection element through an internally preset algorithm to generate dynamic current control signals for each electromagnetic coil 212 inside the moving magnetorheological roller 21 and the fixed magnetorheological roller 22. This allows the magnetorheological fluid in the annular cavity 216 to rapidly change its viscosity and hardness according to the undulations of different positions on the circuit board, thereby causing the flexible sleeve 213 to produce elastic deformation that matches the circuit board profile. This enables precise and dynamic pressing and repair of warped parts on the circuit board, ensuring the flatness of the circuit board surface and the adhesion quality of the dry film after lamination.

[0022] The lifting component 210 includes a connecting plate 2101, a drive source 2102, a lead screw 2103, and a moving block 2104. The connecting plate 2101 is mounted on the rack cabinet 4 and is connected to the drive source 2102. The output end of the drive source 2102 is connected to the lead screw 2103, and the lead screw 2103 is threadedly connected to the moving block 2104. The drive source 2102 is a drive motor. During operation, the moving magnetorheological roller 21 detects the pressing gap according to the detection element and needs to be adjusted to a suitable pressing position. When the drive source 2102 runs, the output shaft of the drive source 2102 drives the lead screw 2103 to rotate. The moving block 2104 moves linearly along the axial direction of the lead screw 2103, which drives the entire moving magnetorheological roller 21 to move up and down synchronously. This precisely adjusts the distance between the moving magnetorheological roller 21 and the fixed magnetorheological roller 22 to adapt to the pressing requirements of circuit boards of different thicknesses and ensures that the initial setting of the pressing pressure is accurate.

[0023] A gear ring 2141 is provided on the sealing key 214, and a support plate 2105 is provided on the moving block 2104. A second drive source 2106 is provided on the support plate 2105, and a gear 2107 is provided at the output end of the second drive source 2106. The gear 2107 is meshed with the gear ring 2141. The second drive source 2106 is a drive motor. When the film pressing operation is performed, the second drive source 2106 runs, and the output shaft of the second drive source 2106 drives the gear 2107 to rotate. Because the gear 2107 and the sealing key 2141 are connected, the second drive source 2106 rotates. The gear ring 2141 meshes with the gear 2107, so the rotation of the gear 2107 will drive the gear ring 2141 to rotate synchronously, which in turn drives the sealing key 214 and the flexible sleeve 213 connected to it to rotate around the axis of the stator shaft 211. When the moving magnetorheological roller 21 and the fixed magnetorheological roller 22 cooperate to press the circuit board, the flexible sleeve 213 can rotate actively, cooperate with the conveying of the circuit board, realize the continuous and uniform rolling of the dry film on the surface of the circuit board, and ensure the stability of the pressing process and the pressing quality.

[0024] It also includes a magnetic isolation ring 217, which is sleeved on the stator shaft 211 and located between two electromagnetic coils 212. The electromagnetic coils 212 are covered with magnetic pole shoes. During operation, a magnetic isolation ring 217 is provided between every two coils to ensure that the magnetic field generated by each coil radiates only vertically outward, and the magnetic fields of adjacent sections do not interfere with each other, thus avoiding magnetic crosstalk. The magnetic pole shoes covering the outside of the electromagnetic coils 212 ensure that the magnetic field will never leak and penetrate to the circuit board outside. This not only protects the electronic components of the circuit board, but also maximizes the magnetization efficiency of the magnetorheological fluid.

[0025] It also includes a pressure relief and discharge device 3, which comprises an adjusting roller group 31, a fixed roller group 32, and a cooling air duct. The adjusting roller group 31 is slidably mounted on the frame cabinet 4, and the fixed roller group 32 is fixedly mounted on the frame cabinet 4. A cooling air duct is provided between every two rollers of the adjusting roller group 31 and the fixed roller group 32. During operation, the circuit board after pressing first enters the conveying channel formed by the adjusting roller group 31 and the fixed roller group 32. The adjusting roller group 31 can be adaptively slidably adjusted on the frame cabinet 4 according to the thickness of the circuit board to ensure that a suitable clamping gap is formed between it and the fixed roller group 32. This ensures that the circuit board can be conveyed smoothly and that appropriate pressure is applied to assist in stress release. During the conveying process, due to the staggered arrangement of the adjusting roller group 31 and the fixed roller group 32, the conveying path of the circuit board naturally forms an extremely small S-shaped wave trajectory. As the circuit moves forward along this wave-shaped trajectory, the molecular chains inside the highly elastic dry film and the circuit board substrate are subjected to alternating stretching and compression as the circuit board bends. This repeated micro-bending deformation effectively breaks, disperses, and releases the residual rigid thermal stress generated by high temperature and pressure during the lamination process. At the same time, the cooling air ducts set between every two rollers of the adjusting roller group 31 and the fixed roller group 32 start working, blowing temperature-controlled cooling airflow onto the upper and lower surfaces of the circuit board to rapidly and uniformly cool the circuit board through convection. After the residual stress is fully released, the circuit board quickly solidifies and sets under the cooling effect, thereby effectively preventing possible warping deformation in the future. Finally, the circuit board that has undergone stress release and cooling and setting is smoothly conveyed to the discharge port of the equipment, completing the unloading of the entire lamination process.

[0026] Working principle of the invention: During operation, the circuit board is manually placed onto the conveyor roller 111. The conveyor roller 111 rotates to transport the circuit board toward the magnetofluidic molding device 2. At the same time, the dry film wound on the high-position roller 112 and the low-position roller 113 begin to unwind. After the dry film is peeled off from the high-position roller 112 and the low-position roller 113, the heating tube is energized and heats up. The dry film slides along the surface of the heating module of the preheating component 12. The heat is evenly radiated onto the dry film through the arc-shaped residual heat plate 121. The heating module in the preheating component 12 quickly heats the dry film to the preset softening temperature, giving the dry film good plasticity and preparing it for subsequent tight pressing with the circuit board.

[0027] Before the circuit board enters the magnetorheological molding device 2, the pressing gap and undulation profile of the circuit board are scanned and detected by the detection element. After the circuit board enters the magnetorheological molding device 2, the movable magnetorheological roller 21 is adjusted to a suitable pressing position according to the pressing gap detected by the detection element. The drive source 2102 runs, and the output shaft of the drive source 2102 drives the lead screw 2103 to rotate. The moving block 2104 moves linearly along the axial direction of the lead screw 2103, which drives the entire movable magnetorheological roller 21 to move up and down synchronously, thereby accurately adjusting the distance between the movable magnetorheological roller 21 and the fixed magnetorheological roller 22 to adapt to the pressing requirements of circuit boards of different thicknesses.

[0028] After the movable magnetorheological roller 21 is adjusted to the correct position, the PLC outputs dynamic current to the electromagnetic coils 212 inside the movable magnetorheological roller 21 and the fixed magnetorheological roller 22 in real time according to the undulating contour detected by the detection element. The stator shaft 211 is a hollow shaft with a hollow channel inside for arranging the control lines of the electromagnetic coils 212. Under the influence of the magnetic field released by the energized electromagnetic coils 212, the magnetorheological fluid in the annular cavity 216 causes the nano-iron particles inside the magnetorheological fluid to arrange into iron chains, and the liquid immediately becomes a hard semi-solid. The flexible sleeve 213 has strong internal support and can press and repair the warped parts on the circuit board. After the molding is completed, the circuit board leaves the magnetorheological molding device 2.

[0029] After lamination, the circuit board first enters the conveying channel composed of the adjusting roller group 31 and the fixed roller group 32. The adjusting roller group 31 can be adaptively slidably adjusted on the rack cabinet 4 according to the thickness of the circuit board to ensure that a suitable clamping gap is formed between it and the fixed roller group 32. This ensures that the circuit board can be conveyed smoothly and that appropriate pressure is applied to assist in stress release. During the conveying process, due to the staggered arrangement of the adjusting roller group 31 and the fixed roller group 32, the conveying path of the circuit board naturally forms an extremely small S-shaped wave trajectory. When the circuit board moves forward along this wave-shaped trajectory, the molecular chains inside the highly elastic dry film and the circuit board substrate will be continuously subjected to alternating stretching and compression as the circuit board bends. This repeated micro-bending deformation can effectively break, disperse and release the residual rigid thermal stress generated by high temperature and pressure during the lamination process.

[0030] At the same time, the cooling air ducts set between every two rollers of the adjusting roller group 31 and the fixed roller group 32 start working, blowing temperature-controlled cooling airflow onto the upper and lower surfaces of the circuit board, performing rapid and uniform convective cooling on the circuit board. After the residual stress is fully released, the circuit board quickly solidifies and sets under the cooling effect, thereby effectively preventing possible warping deformation in the future. Finally, the circuit board that has undergone stress release and cooling and setting is smoothly conveyed to the discharge port of the equipment, completing the unloading of the entire lamination process.

[0031] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

Claims

1. A circuit board laminating device with anti-warping function, characterized in that: It includes an inlet preheating device (1), a magnetorheological molding device (2), a pressure relief and discharge device (3), and a frame cabinet (4). The inlet preheating device (1) and the pressure relief and discharge device (3) are both installed on the frame cabinet (4). The magnetorheological molding device (2) includes a movable magnetorheological pressure roller (21) and a fixed magnetorheological pressure roller (22). The movable magnetorheological roller (21) includes a stator shaft (211), an electromagnetic coil (212), a flexible sleeve (213), and a lifting component (210). The lifting component (210) is mounted on the frame cabinet (4), and the stator shaft (211) is mounted on the lifting component (210). An electromagnetic coil (212) is axially mounted on the outer wall of the stator shaft (211), and a sealing key (214) is rotatably mounted on the stator shaft (211). (214) is connected to the flexible sleeve (213). The flexible sleeve (213) is a double-layer composite structure. The inner side of the flexible sleeve (213) is a flexible rotating skeleton. The outer side of the flexible rotating skeleton is covered with a thermally conductive silicone layer. A closed annular cavity (216) is formed between the stator shaft (211) and the flexible sleeve (213). The annular cavity (216) is filled with magnetorheological fluid. The fixed magnetorheological pressure roller (22) is set in the rack cabinet (4).

2. The circuit board laminating device with anti-warping function according to claim 1, characterized in that: The lifting component (210) includes a connecting plate (2101), a drive source (2102), a lead screw (2103), and a moving block (2104). The connecting plate (2101) is mounted on the rack cabinet (4). The connecting plate (2101) is connected to the drive source (2102). The output end of the drive source (2102) is connected to the lead screw (2103). The lead screw (2103) is threadedly connected to the moving block (2104).

3. A circuit board laminating device with anti-warping function according to claim 2, characterized in that: A toothed ring (2141) is provided on the sealing key (214), a support plate (2105) is provided on the moving block (2104), a second drive source (2106) is provided on the support plate (2105), and a gear (2107) is provided at the output end of the second drive source (2106). The gear (2107) meshes with the toothed ring (2141).

4. A circuit board laminating device with anti-warping function according to claim 1, characterized in that: It also includes a magnetic shielding ring (217), which is sleeved on the stator shaft (211) and located between two electromagnetic coils (212), with magnetic pole shoes covering the outside of the electromagnetic coils (212).

5. A circuit board laminating device with anti-warping function according to claim 1, characterized in that: It also includes a detection element and a control system, both of which are electrically connected to the control system.

6. A circuit board laminating device with anti-warping function according to claim 1, characterized in that: The inlet preheating device (1) includes an inlet component (11) and a preheating component (12). The inlet component (11) includes a conveyor roller (111), a high-position reel (112), and a low-position reel (113). The conveyor roller (111), the high-position reel (112), and the low-position reel (113) are all rotatably mounted on the rack cabinet (4). The preheating component (12) is connected to the rack cabinet (4).

7. A circuit board laminating device with anti-warping function according to claim 6, characterized in that: The preheating component (12) includes an arc-shaped waste heat plate (121) and a temperature detection element. The arc-shaped waste heat plate (121) and the temperature detection element are both mounted on the rack cabinet (4). A heating tube is provided on the back of the arc-shaped waste heat plate (121).

8. A circuit board laminating device with anti-warping function according to claim 1, characterized in that: The pressure relief discharge device (3) includes an adjusting roller group (31), a fixed roller group (32) and a cooling air duct. The adjusting roller group (31) is slidably mounted on the frame cabinet (4), and the fixed roller group (32) is fixedly mounted on the frame cabinet (4). A cooling air duct is provided between every two roller shafts of the adjusting roller group (31) and the fixed roller group (32).

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