Multi-layer circuit board pressing device and pressing method
By using a continuous coating process and a dual-roller design for the coating assembly, the problem of wasted prepreg in the lamination of multilayer circuit boards is solved, achieving efficient material utilization and cost reduction.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- HUIZHOU TAISHENG ELECTRONICS CO LTD
- Filing Date
- 2026-02-11
- Publication Date
- 2026-05-01
- Estimated Expiration
- Not applicable · inactive patent
AI Technical Summary
During the lamination process of multilayer circuit boards, the cutting and stacking of prepregs leads to significant waste of scrap materials, increasing production costs.
A continuous lamination process is adopted, in which the rolled prepreg is pulled by lamination rollers with corresponding left and right displacements, so that it is stretched to cover the inner circuit board. The double roller design of the lamination assembly reduces the oversize allowance reserved in the movement trajectory of the lamination rollers. Combined with the double roller structure of the film pulling assembly, it ensures that the prepreg is in a stable tension and within a controlled coverage range at the moment of laying.
It significantly reduces the amount of scrap material that needs to be cut after lamination, lowers the consumption of prepreg and the cost of scrap material disposal, and improves material utilization.
Smart Images
Figure CN121968477A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of circuit board manufacturing technology, and in particular to a multilayer circuit board laminating device and laminating method. Background Technology
[0002] Before the traditional lamination process of multilayer boards, the materials used, such as prepreg rolls, need to be cut into uniformly sized sheets. Then, multiple prepreg sheets are alternately stacked with multiple inner circuit boards. However, the prepreg sheets are prone to wrinkling during the stacking process, which affects the subsequent lamination.
[0003] In response, existing technologies propose to abandon the processing approach of equally cutting rolled prepreg sheets, and instead directly pull the rolled prepreg sheets by left and right corresponding displacement coating rollers, so that each layer of prepreg sheet is in a taut state, thus solving the wrinkling problem caused by alternating layers with the inner circuit board.
[0004] However, this method still has shortcomings, such as Figure 8 As shown, in the prior art, the prepreg 11, pulled into a roll by the coating roller 13, covers the inner circuit board 12. To ensure that the prepreg 11 remains taut and avoids wrinkles under the action of the coating roller 13, and can completely cover the inner circuit board 12, the coverage area of the prepreg 11 must exceed the actual size of the inner circuit board 12, leaving extra material allowance to accommodate the movement trajectory and traction of the coating roller 13. This extra material allowance is also known as scrap material (see...). Figure 1 (In the dashed box area), as the number of layers of prepreg 11 increases, the amount of reserved scrap material increases exponentially. After the lamination process is completed, all scrap material that exceeds the edge of the formed circuit board needs to be cut off. However, the cut scrap material cannot be directly reused, resulting in a large amount of material waste and increased production costs. Summary of the Invention
[0005] The purpose of this invention is to provide a multilayer circuit board lamination device and lamination method to solve the problem of excessive waste of prepreg when laminating multilayer circuit boards using a continuous coating process.
[0006] To achieve this objective, the present invention adopts the following technical solution: A multilayer circuit board laminating device is provided, including a base disposed on a workbench and a laminating mechanism disposed above the base, a film-coating assembly for laying a prepreg is provided between the base and the laminating mechanism, and a clamping assembly disposed on one side of the base, an unwinding roller disposed on one side of the laminating mechanism, and a support frame that is movably disposed between the clamping assembly and the unwinding roller. The coating assembly includes a left coating roller and a right coating roller that are synchronously and laterally slidably disposed on the support frame. The left coating roller and the right coating roller are spaced apart and their axes are both parallel to the axis of the unwinding roller. One side of the prepreg wound on the unwinding roller passes through the gap between the left coating roller and the right coating roller and is connected to the clamping assembly to straighten the prepreg and cover the surface of the inner circuit board before pressing.
[0007] Preferably, the support frame includes a front support plate and a rear support plate, with a horizontal plate connecting the two ends of the front and rear support plates, and an upper drive component for driving the support frame to rise and fall is provided between the horizontal plate and the worktable.
[0008] Preferably, the front support plate and the rear support plate are respectively provided with a sliding groove extending in the lateral direction, and a sliding slider is provided in the sliding groove. The two ends of the left coating roller and the right coating roller are respectively connected to the corresponding slider.
[0009] Preferably, one side of the horizontal plate is provided with a first driving mechanism for driving the two sliders to move synchronously and in the same direction along the slide groove, so as to drive the left and right coating rollers to move laterally as a whole.
[0010] Preferably, the rear support plate has rotatable pressing arms on both sides of the groove, pressing rollers at the free ends of the pressing arms, and a second driving mechanism for driving the pressing arms to rotate on the rear support plate.
[0011] Preferably, a first connecting plate is provided between the two ends of the left and right coating rollers and the corresponding sliders. The first connecting plate is provided with an upwardly extending support rod. A second connecting plate is provided at the upper end of the support rod. A film pulling assembly is provided between the two second connecting plates.
[0012] Preferably, the film-pulling assembly includes a left traction roller and a right traction roller spaced apart. One side of the semi-cured sheet wound on the unwinding roller passes sequentially through the gap between the left traction roller and the right traction roller, and the gap between the left coating roller and the right coating roller, and is connected to the clamping assembly.
[0013] Preferably, the spacing between the film-drawing assembly and the film-coating assembly is greater than the thickness of a single inner layer circuit board.
[0014] A method for laminating multilayer circuit boards is also provided, relating to a multilayer circuit board laminating apparatus as described in any of the preceding claims, the method comprising: S1, place the inner circuit board on the pressing area of the base; S2, the prepreg is released by the unwinding roller, passes through the coating mechanism, and is fixed by the clamping assembly; S3, drive the support frame to rise, so that the coating mechanism presses the prepreg in a tensioned state onto the surface of the inner circuit board. S4. While maintaining the prepreg tension, adjust the lateral position of the coating mechanism so that the prepreg covers the effective area of the inner circuit board. S5, stack the next inner layer circuit board in the corresponding lamination area, repeat steps S3 to S4 to complete the alternating stacking of multiple inner layer circuit boards and prepreg. S6, start the pressing mechanism to complete the overall pressing and molding.
[0015] Compared with the prior art, the present invention has the following beneficial effects: Combining the aforementioned apparatus and method, the prepreg process is transformed from a discrete process of cutting and stacking to a continuous laying process. This ensures that each layer of prepreg is within a stable tension and controlled coverage range immediately upon laying, reducing the risk of rework due to wrinkles and curling edges from the outset. The dual-roller design of the laminating assembly reduces the oversize allowance reserved for the laminating roller's movement trajectory, significantly reducing the amount of scrap material that needs to be trimmed after lamination. This avoids the exponential increase in material waste that occurs with the number of layers, directly reducing prepreg consumption and scrap material costs. Attached Figure Description
[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.
[0017] The structures, proportions, sizes, etc., shown in the accompanying drawings of this specification are only for the purpose of assisting those skilled in the art in understanding and reading the content disclosed in the specification, and are not intended to limit the conditions under which the present invention can be implemented. Therefore, they have no substantial technical significance. Any modifications to the structure, changes in the proportions, or adjustments to the size, without affecting the effects and objectives that the present invention can produce, should still fall within the scope of the technical content disclosed in the present invention.
[0018] Figure 1 This is a schematic diagram of a multilayer circuit board laminating device with a front support plate. Figure 2 A schematic diagram of a multilayer circuit board laminating device for laying the first layer of prepreg; Figure 3 A schematic diagram of a multilayer circuit board laminating device where the edge-pressing arm is not pressed down when laying the second layer of prepreg; Figure 4 A schematic diagram of a multilayer circuit board laminating device where the edge-pressing arm has been pressed down when laying the second layer of prepreg; Figure 5This is a schematic diagram of a multilayer circuit board laminating device with a traction component. Figure 6 This is a schematic diagram of a multilayer circuit board laminating device with six inner circuit board layers stacked together. Figure 7 A flowchart illustrating the steps of a multilayer circuit board lamination method; Figure 8 This is a schematic diagram of the structure of the coating roller used in the background art.
[0019] Illustration: 11. Prepreg; 12. Inner circuit board; 13. Coating roller; 131. Left coating roller; 132. Right coating roller; 14. Clamping assembly; 15. Unwinding roller; 16. Pressing mechanism; 17. Base; 21. Front support plate; 22. Rear support plate; 23. Horizontal plate; 24. Slider; 25. First drive mechanism; 26. Second drive mechanism; 27. Edge pressing arm; 271. Edge pressing roller; 28. First connecting plate; 29. Second connecting plate; 30. Left traction roller; 31. Right traction roller; 32. Arc transition section; 33. Top drive component. Detailed Implementation
[0020] To make the objectives, features, and advantages of this invention more apparent and understandable, the technical solutions of the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the embodiments described below are only some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.
[0021] In the description of this invention, it should be understood that the terms "upper," "lower," "top," "bottom," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. It should be noted that when a component is considered to be "connected" to another component, it can be directly connected to the other component or there may be a component positioned centrally in the connection.
[0022] The technical solution of the present invention will be further described below with reference to the accompanying drawings and specific embodiments.
[0023] Please see Figures 1-6 .
[0024] This invention provides a multilayer circuit board laminating device, including a base 17 disposed on a workbench and a laminating mechanism 16 disposed above the base 17. A film-coating assembly for laying a prepreg 11 is provided between the base 17 and the laminating mechanism 16.
[0025] The above-mentioned device also includes a clamping assembly 14 disposed on one side of the base 17, an unwinding roller 15 disposed on one side of the pressing mechanism 16, and a support frame that is movably disposed between the clamping assembly 14 and the unwinding roller 15.
[0026] The coating assembly includes a left coating roller 131 and a right coating roller 132 that are synchronously and laterally slidably disposed on the support frame. The left coating roller 131 and the right coating roller 132 are spaced apart and their axes are parallel to the axis of the unwinding roller 15. One side of the prepreg 11 wound on the unwinding roller 15 passes through the gap between the left coating roller 131 and the right coating roller 132 and is connected to the clamping assembly 14 so as to straighten the prepreg 11 and cover the surface of the inner circuit board 12 before pressing.
[0027] It should be noted that when implementing the above embodiments, it is necessary to ensure that the semi-cured sheet 11 always maintains continuity with the unwinding direction so that the coating assembly can play the role of pressing and tension control.
[0028] For example, in the lamination of 6-layer or 8-layer FR-4 multilayer boards, the size of the inner circuit board 12 is 457×610mm. Traditional technology requires the prepreg 11 to be cut into sheets larger than this size, such as 500×650mm. When using the above device, the prepreg 11 roll is directly unwound and is stretched and covered at the moment of lamination. The actual laying width is precisely controlled near the effective area of the inner board.
[0029] Specifically, such as Figure 2 As shown, the clamping assembly 14 is located on the left side and the unwinding roller 15 is located on the right side. The gripping mechanism or manual operation places the inner circuit board 12 of the first layer on the base 17 at the pressing area corresponding to the pressing mechanism 16. The coating assembly is adjusted to a preset height by controlling the up and down displacement of the support frame. The coating assembly is then further controlled to move to the right, so that the left coating roller 131 drives the semi-cured sheet 11 to cover the surface of the inner circuit board 12 of the first layer.
[0030] At this time, the coating assembly causes the coverage area of the prepreg 11 to continue to exceed the actual size of the inner circuit board 12, so as to leave space for the placement of the second inner circuit board 12 and to further tighten the first layer of prepreg 11 to avoid wrinkles.
[0031] Next, the same area is used to stack the second inner layer circuit board 12. Then, the coating assembly is raised to the height of the sum of the thickness of the inner layer circuit board 12 and the prepreg layer 11, and the coating assembly is moved to the left. The right coating roller 132 then pulls the subsequent prepreg 11 to cover the surface of the second inner layer circuit board 12. Simultaneously, the prepreg 11 wraps around the side of the second inner layer circuit board 12, forming an arc-shaped transition section 32. It should be noted that the diameter of this arc-shaped transition section 32 decreases with the traction force of the coating assembly moving continuously to the left, until it is maintained at a specific bending radius to prevent deformation or breakage.
[0032] This process is repeated to create a multilayer circuit board with a predetermined number of layers to be laminated. For example... Figure 6 As shown, multiple arc transition portions 32 are alternately formed on both sides of the multilayer circuit board to be pressed. Obviously, the diameter of each arc transition portion 32 is smaller than the diameter of any coating roller. The multilayer circuit board to be pressed only occupies a small amount of extra material to avoid deformation or breakage of the prepreg 11. There is no need to reserve a spare amount for the traction of the coating roller, thus avoiding large-area waste of scrap material.
[0033] In another embodiment, the support frame includes a front support plate 21 and a rear support plate 22, with a horizontal plate 23 connecting the two ends of the front support plate 21 and the rear support plate 22. An upper drive member 33 for driving the support frame to rise and fall is provided between the horizontal plate 23 and the worktable.
[0034] It should be noted that the upper drive component 33 can be a lifting cylinder, and this embodiment is not limited to this. The front support plate 21, the rear support plate 22, and the horizontal plate 23 between the two ends form a rectangular frame structure, which is synchronously raised and lowered by the upper drive component 33. For example, when laying the first inner layer circuit board, the support frame drives the film coating assembly to the upper position so that the prepreg 11 is above the first inner layer circuit board. Under the adjustment action of the stroke movement of the upper drive component 33, before laying the prepreg 11 on the first inner layer circuit board, the bottom surface of the prepreg 11 is placed against the top corner of the first inner layer circuit board.
[0035] In another embodiment, the front support plate 21 and the rear support plate 22 are respectively provided with transversely extending grooves, and the grooves are provided with slidable sliders 24. The two ends of the left coating roller 131 and the right coating roller 132 are respectively connected to the corresponding sliders 24.
[0036] The left coating roller 131 and the right coating roller 132 move synchronously along the groove between the two sliders 24 to ensure that when sliding to the right, the left coating roller 131 can act on one side of the prepreg 11; when sliding to the left, the right coating roller 132 can act on the other side of the prepreg 11.
[0037] In this embodiment, the driving force of the coating component is not limited.
[0038] On the other hand, the left coating roller 131 and the right coating roller 132 are arranged in parallel and are both perpendicular to the slider 24. When the whole slides, the two rollers restrict each other and the rollers on one side cannot be deflected. The structure is more rigid and avoids the phenomenon of horizontal tilting caused by sliding on one side, which would cause the semi-cured sheet 11 to wrinkle obliquely.
[0039] One side of the horizontal plate 23 is provided with a first driving mechanism 25 for driving the two sliders 24 to move synchronously and in the same direction along the slide groove, so as to drive the left coating roller 131 and the right coating roller 132 to move laterally as a whole.
[0040] A drive mechanism is set up to drive the two sliders 24 to move synchronously, thereby controlling the overall movement of the coating assembly. For example, the first drive mechanism 25 may include a lead screw and a drive motor. Lead screws are provided in both sliding grooves, passing through the corresponding sliders 24. The lead screws are threadedly engaged with the sliders 24, and the ends of the two lead screws on the same side extend to the outside of the horizontal plate 23. One end of one lead screw is connected to the drive motor and then connected to the end of the other lead screw via a belt drive, thereby enabling the drive motor to synchronously drive the two lead screws to rotate in the same direction, thus moving the sliders 24. The drive mechanism can also be other drive forms such as rodless cylinders; this embodiment is not limited to these.
[0041] In another embodiment, the rear support plate 22 has rotatable pressing arms 27 on both sides of the groove, the free end of the pressing arms 27 is provided with pressing rollers 271, and the rear support plate 22 is provided with a second driving mechanism 26 for driving the pressing arms 27 to rotate.
[0042] It should be noted that during the process of laying the second or higher layers of the prepreg 11, the edge of the corresponding inner circuit board is easily lifted or curled up under the action of traction, causing edge wrinkles.
[0043] The second drive mechanism 26 drives the free end of the pressing arm 27 to swing, so that the pressing roller 271 presses the starting edge of the prepreg 11 at the moment when the current layer begins to be laid, which can prevent it from lifting up, thereby eliminating edge wrinkles and improving the edge pressing consistency of the multilayer board.
[0044] In another embodiment, a first connecting plate 28 is provided between the two ends of the left coating roller 131 and the right coating roller 132 and the corresponding slider 24. The first connecting plate 28 is provided with an upwardly extending support rod. The upper end of the support rod is provided with a second connecting plate 29. A film pulling assembly is provided between the two second connecting plates 29.
[0045] like Figure 4 , 5As shown, it should be noted that relying solely on the tensioning of the laminating assembly requires a relatively long stretch allowance. Specifically, when the laminating assembly rises to begin laying a new layer, the front and rear prepreg sheets 11 at the stretching point can easily form an "angle." To avoid interference from this angle with the new inner circuit board, the laminating assembly needs to move further outward, which requires a longer stretching path and results in material redundancy.
[0046] The film-pulling assembly moves the "angle" upward through upstream pre-tensioning, perfectly avoiding the new inner circuit board and facilitating its stacking. At this time, the film-coating assembly only needs to undertake the horizontal laying task without excessive stroke, making the overall structure more compact. This significantly reduces the allowance required for the prepreg 11, improves material utilization, and reduces production costs.
[0047] The film-pulling assembly includes a left traction roller 30 and a right traction roller 31 spaced apart. One side of the semi-cured sheet 11 wound around the unwinding roller 15 passes sequentially through the gap between the left traction roller 30 and the right traction roller 31, and the gap between the left coating roller 131 and the right coating roller 132, and is connected to the clamping assembly 14.
[0048] The distance between the film-drawing assembly and the film-coating assembly is greater than the thickness of a single inner layer circuit board 12.
[0049] By setting the film-pulling mechanism to a dual-roller structure, the prepreg 11 is made into a stable pre-tensioned state before entering the coating mechanism, avoiding uneven tension and material wrinkling caused by single-point traction. Specifically, considering that the prepreg 11 is made of resin and is not fully cured, and has a certain degree of stickiness on its surface, the mechanism avoids the prepreg 11 vibrating when a single traction roller moves in one direction and momentarily detaches from the prepreg 11, causing local deformation of the prepreg 11 and affecting the laying effect.
[0050] Furthermore, the use of dual traction rollers can also homogenize the tensile stress of the pre-passed prepreg 11 in the width direction, so that the prepreg 11 entering the coating assembly has a uniform shape and avoids laying wrinkles.
[0051] By setting the spacing between the film-pulling assembly and the film-coating assembly to be greater than the thickness of a single inner layer circuit board 12, on the one hand, the film-pulling mechanism is prevented from interfering with the placement of the inner layer circuit board, and on the other hand, a free-suspension tensioned film segment is formed between the film-pulling mechanism and the film-coating mechanism. The tension of this film segment is sufficiently stable within the segment, and the prepreg 11 is in a uniformly stretched state during film coating.
[0052] In combination with any of the above embodiments, such as Figure 7 As shown, this application also provides a method for laminating multilayer circuit boards, including: S1, place the inner circuit board 12 on the pressing area of the base 17; S2, the semi-cured sheet 11 is released by the unwinding roller 15, so that the semi-cured sheet 11 passes through the coating mechanism and is fixed by the clamping assembly 14; S3, drive the support frame to rise, so that the coating mechanism presses the prepreg 11 in a tensioned state onto the surface of the inner circuit board 12. S4. While maintaining the prepreg 11 in a taut state, adjust the lateral position of the coating mechanism so that the prepreg 11 covers the effective area of the inner circuit board 12. S5, the next inner layer circuit board 12 is stacked in the corresponding pressing area, and steps S3 to S4 are repeated to complete the alternating stacking of the multi-layer inner layer circuit board 12 and the prepreg 11. S6, start the pressing mechanism 16 to complete the overall pressing and molding.
[0053] Combining the aforementioned apparatus and method, the prepreg process is transformed from a discrete process of cutting and stacking to a continuous laying process. This ensures that each layer of prepreg is within a stable tension and controlled coverage range immediately upon laying, reducing the risk of rework due to wrinkles and curling edges from the outset. The dual-roller design of the laminating assembly reduces the oversize allowance reserved for the laminating roller's movement trajectory, significantly reducing the amount of scrap material that needs to be trimmed after lamination. This avoids the exponential increase in material waste that occurs with the number of layers, directly reducing prepreg consumption and scrap material costs.
[0054] The above-described embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit it. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some of the technical features. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.
Claims
1. A multilayer circuit board laminating device, comprising a base (17) disposed on a workbench and a laminating mechanism (16) correspondingly disposed above the base (17), wherein a coating assembly for laying a prepreg (11) is provided between the base (17) and the laminating mechanism (16), characterized in that, It also includes a clamping assembly (14) disposed on one side of the base (17), an unwinding roller (15) disposed on one side of the pressing mechanism (16), and a support frame that is movably disposed between the clamping assembly (14) and the unwinding roller (15). The coating assembly includes a left coating roller (131) and a right coating roller (132) that are synchronously and laterally slidably mounted on the support frame. The left coating roller (131) and the right coating roller (132) are spaced apart and their axes are parallel to the axis of the unwinding roller (15). One side of the prepreg (11) wound on the unwinding roller (15) passes through the gap between the left coating roller (131) and the right coating roller (132) and is connected to the clamping assembly (14) to straighten the prepreg (11) and cover the surface of the inner circuit board (12) before pressing.
2. The multilayer circuit board laminating device according to claim 1, characterized in that, The support frame includes a front support plate (21) and a rear support plate (22). A horizontal plate (23) is connected between the two ends of the front support plate (21) and the rear support plate (22). An upper drive component (33) for driving the support frame to rise and fall is provided between the horizontal plate (23) and the worktable.
3. The multilayer circuit board laminating device according to claim 2, characterized in that, The front support plate (21) and the rear support plate (22) are respectively provided with transversely extending grooves, and the grooves are provided with slidable sliders (24). The two ends of the left coating roller (131) and the right coating roller (132) are respectively connected to the corresponding sliders (24).
4. The multilayer circuit board laminating device according to claim 3, characterized in that, The horizontal plate (23) is provided with a first driving mechanism (25) on one side for driving the two sliders (24) to move synchronously and in the same direction along the slide groove, so as to drive the left coating roller (131) and the right coating roller (132) to move laterally as a whole.
5. The multilayer circuit board laminating device according to claim 2, characterized in that, The rear support plate (22) has rotatable pressing arms (27) on both sides of the groove. The free end of the pressing arm (27) is provided with a pressing roller (271). The rear support plate (22) is provided with a second driving mechanism (26) for driving the pressing arm (27) to rotate.
6. The multilayer circuit board laminating device according to claim 3, characterized in that, The left coating roller (131) and the right coating roller (132) are provided with a first connecting plate (28) between their ends and the corresponding slider (24). The first connecting plate (28) is provided with an upwardly extending support rod. The upper end of the support rod is provided with a second connecting plate (29). A film pulling assembly is provided between the two second connecting plates (29).
7. The multilayer circuit board laminating device according to claim 6, characterized in that, The film-pulling assembly includes a left traction roller (30) and a right traction roller (31) spaced apart. One side of the semi-cured sheet (11) wound on the unwinding roller (15) passes sequentially through the gap between the left traction roller (30) and the right traction roller (31), as well as the gap between the left coating roller (131) and the right coating roller (132), and is connected to the clamping assembly (14).
8. The multilayer circuit board laminating device according to claim 6, characterized in that, The distance between the film-drawing assembly and the film-coating assembly is greater than the thickness of a single inner layer circuit board (12).
9. A method for laminating multilayer circuit boards, relating to the multilayer circuit board laminating apparatus according to any one of claims 1-8, characterized in that, The method includes: S1, place the inner circuit board (12) on the pressing area of the base (17); S2, the prepreg (11) is released by the unwinding roller (15), so that the prepreg (11) passes through the coating mechanism and is fixed by the clamping assembly (14); S3, drive the support frame to rise, so that the coating mechanism presses the prepreg (11) in a tensioned state onto the surface of the inner circuit board (12); S4. While keeping the prepreg (11) in a taut state, adjust the lateral position of the coating mechanism so that the prepreg (11) covers the effective area of the inner circuit board (12). S5, stack the next inner layer circuit board (12) in the corresponding pressing area, repeat steps S3 to S4 to complete the alternating stacking of the multi-layer inner layer circuit board (12) and the prepreg (11); S6, start the pressing mechanism (16) to complete the overall pressing and molding.