A multilayer printed flexible circuit board

Abstract

A multilayer printed flexible circuit board includes a substrate and copper foil. The upper end of the substrate is fixedly connected to the copper foil, the upper end of the copper foil is fixedly connected to a cover layer, the upper end of the cover layer is fixedly connected to a reinforcing plate, and the upper end of the reinforcing plate is fixedly connected to a shielding layer. A protective mechanism is connected to the outer wall of the shielding layer. The protective mechanism's outer shell and shielding layer are connected in a movable manner, allowing for quick installation or disassembly without complex tools. The sliding engagement of the trapezoidal groove and connecting strip further reduces assembly steps, making the installation of the limiting mechanism more convenient. Simultaneously, the snap-fit ​​between the connecting cap and connecting rod shortens the operation of limiting multiple positions; simple pressing is sufficient for fixation, achieving installation without the need for special tools. This efficient and rapid assembly greatly facilitates practical applications.

Description

Technical Field

[0001] This utility model relates to the field of flexible circuit board technology, and in particular to a multilayer printed flexible circuit board. Background Technology

[0002] Flexible circuit boards are lightweight, thin, and can be bent and folded freely, making them widely used in electronic products. As circuit board designs become increasingly precise and dense, they have broken through traditional interconnection technologies. The materials that make up the structure of flexible circuits are insulating films, conductors, and adhesives.

[0003] For example, a multilayer printed flexible circuit board with publication number "CN217693844U" solves the problem that existing multilayer printed flexible circuit boards cannot guarantee the dustproof effect of the internal circuit after installation. However, the user needs to remove the card strip from the pre-set card slot and then pull the second pin out from the inner wall of the second blind hole. Subsequently, the user uses the slider to pull the card block to the left. At this time, the card block will form a sliding connection with the inner wall of the round hole. When the outer edge of the right side of the card block reaches the inner wall of the left side of the second blind hole, the second pin is inserted into the inner wall of the second blind hole. At this time, under the blocking action of the second pin and the elastic force of the first spring, the outer edge of the right side of the slider will overlap with the outer edge of the left side of the second pin. Considering that existing multilayer printed flexible circuit boards require special tools to achieve this during the assembly process, such as the installation of the pin or the positioning of the card block, the overall assembly speed will be significantly affected. Summary of the Invention

[0004] This invention aims to solve the problems existing in the prior art by providing a multilayer printed flexible circuit board that can be assembled without the need for special tools, thereby improving the overall assembly speed.

[0005] The technical solution adopted by this utility model to solve its technical problem is as follows: Design a multilayer printed flexible circuit board, including a substrate and copper foil. The upper end of the substrate is fixedly connected to the copper foil, the upper end of the copper foil is fixedly connected to a cover layer, the upper end of the cover layer is fixedly connected to a reinforcing plate, the upper end of the reinforcing plate is fixedly connected to a shielding layer, and a protective mechanism is connected to the outer wall of the shielding layer.

[0006] This setup uses PI as the substrate 1, which is heat-resistant and high-strength; copper foil 2 is rolled copper, which is bend-resistant, and its thickness affects performance; cover film 3 is PET, with a thickness of 12.5μm-50μm, protecting the circuit insulation; adhesive bonding reinforcement plate 4, made of FR-4 material, supports the circuit board and prevents bending; and shielding layer 5 is conductive cloth.

[0007] Further improvements include a protective mechanism comprising an outer shell, the inner wall of which is movably connected to a shielding layer, the upper end of which is fixedly connected to a connecting frame, and the upper end of which is fixedly connected to a dustproof layer.

[0008] This protective mechanism effectively isolates external dust and impurities, ensuring stable operation of the internal circuitry, and exhibiting enhanced reliability, especially in highly polluted environments. The synergistic effect of the dustproof layer and the outer casing further improves the overall sealing performance, thereby significantly reducing the failure rate. To further improve the design, a trapezoidal groove is machined on the side end of the outer shell, and a limit mechanism is connected to the outer wall of the trapezoidal groove.

[0009] The trapezoidal groove design makes the installation of the limiting mechanism more convenient, while ensuring the firmness of the connection, thereby improving the reliability of the overall structure.

[0010] In a further improvement, the limiting mechanism includes a connecting strip, the outer wall of which is slidably connected to a trapezoidal groove, the outer wall of which is fixedly connected to a limiting frame, the outer wall of which is movably connected to a connecting rod, the outer wall of the protrusion on the connecting rod engaging with a connecting cap, and the outer wall of the connecting cap abutting against the limiting frame.

[0011] This design, through the cooperation of the connecting strip and the trapezoidal groove, achieves flexible adjustment, while the linkage design of the limit frame and the connecting rod enhances the convenience of modular operation. The snap-fit ​​method of the connecting cap ensures tightness and durability after assembly, preventing loosening issues. Further improvements include a fixed connection between the outer wall of the substrate and the outer connector.

[0012] This external connector design facilitates the connection of the circuit board to other devices, improving the ease of installation and disassembly.

[0013] To further improve the design, the side of the outer shell is machined with an opening.

[0014] This opening helps dissipate internal heat and also facilitates later maintenance and inspection.

[0015] The beneficial effects of this utility model are as follows: By using a movable connection between the outer shell and the shielding layer in the protective mechanism, this utility model can be quickly installed or disassembled without complicated tools. The sliding cooperation between the trapezoidal groove and the connecting strip further reduces the assembly steps, making the installation of the limiting mechanism more convenient. At the same time, the snap-fit ​​between the connecting cap and the connecting rod shortens the operation of limiting too many positions. It can be fixed with just a simple press, achieving an installation method that does not require special tools. This realizes efficient and fast assembly and provides great convenience for practical applications. Attached Figure Description

[0016] Figure 1 This is a three-dimensional schematic diagram of the present invention; Figure 2 for Figure 1 A schematic diagram of the protective structure; Figure 3 for Figure 1 A schematic diagram of the limiting mechanism; Figure 4 for Figure 2 Middle connecting rod structure diagram: Figure 5 for Figure 3 Diagram of the connecting cap structure: Figure 6 for Figure 1 Assembly structure diagram of the substrate and the external connector.

[0017] Explanation of reference numerals in the attached figures: 1. Substrate, 2. Copper foil, 3. Covering layer, 4. Reinforcing plate, 5. Shielding layer, 6. Protective mechanism, 601. Outer shell, 602. Connecting frame, 603. Dustproof layer, 7. Trapezoidal groove, 8. Limiting mechanism, 801. Connecting strip, 802. Limiting frame, 803. Connecting rod, 804. Connecting cap, 9. External base, 10. Opening. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings: Example

[0019] See attached document Figure 1-6 In this embodiment, a multilayer printed flexible circuit board includes a substrate 1 and a copper foil 2. The upper end of the substrate 1 is fixedly connected to the copper foil 2, the upper end of the copper foil 2 is fixedly connected to the cover layer 3, the upper end of the cover layer 3 is fixedly connected to the reinforcing plate 4, the upper end of the reinforcing plate 4 is fixedly connected to the shielding layer 5, and a protective mechanism 6 is connected to the outer wall of the shielding layer 5.

[0020] The protective mechanism 6 includes a housing 601, which shields the upper end through the housing 601 and the dustproof layer 603, thereby achieving the effect of protecting the upper end of the multilayer printed flexible circuit board. The inner wall of the housing 601 is movably connected to the shielding layer 5, the upper end of the housing 601 is fixedly connected to the connecting frame 602, and the upper end of the connecting frame 602 is fixedly connected to the dustproof layer 603.

[0021] The outer end of the outer shell 601 is machined with a trapezoidal groove 7. The outer wall of the trapezoidal groove 7 is connected to a limiting mechanism 8. Through the snap-fit ​​between the connecting cap 804 and the connecting rod 803, the connecting cap 804 tightens the upper and lower space of the outer side of the limiting frame 802. The limiting mechanism 8 includes a connecting strip 801. The outer wall of the connecting strip 801 is slidably connected to the trapezoidal groove 7. The outer wall of the connecting strip 801 is fixedly connected to the limiting frame 802. The outer wall of the limiting frame 802 is movably connected to the connecting rod 803. The outer wall of the connecting rod 803 with the protrusion is snapped with the connecting cap 804. The outer wall of the connecting cap 804 abuts against the limiting frame 802. The outer shell 601 and the shielding layer 5 in the protective mechanism 6 are connected by a movable connection, which can be quickly installed or disassembled without complicated tools. The sliding cooperation between the trapezoidal groove 7 and the connecting bar 801 further reduces the assembly steps, making the installation of the limiting mechanism 8 more convenient. At the same time, the snap-fit ​​between the connecting cap 804 and the connecting rod 803 shortens the operation of limiting multiple positions. It can be fixed by simply pressing, achieving an installation method without the need for special tools. This realizes efficient and fast assembly and provides great convenience for practical applications.

[0022] The outer wall of the substrate 1 is fixedly connected to the outer seat 9, and the side end of the outer shell 601 is machined with an opening 10.

[0023] Working principle: The substrate 1 is made of PI (polyimide), which has high temperature resistance and high mechanical strength. The copper foil 2 on top of the substrate 1 is rolled copper (RA) due to its better bending resistance. The thickness (0.5oz, 1oz, etc.) affects the current carrying capacity and flexibility. The cover film 3 on top of the copper foil 2 is made of PET material, with a thickness of 12.5μm~50μm, used to protect the circuit and provide insulation. The upper end of the cover film 3 is connected to the reinforcing plate 4 with epoxy resin adhesive. The reinforcing plate 4 is made of FR-4 glass fiber material, which has excellent electrical insulation and mechanical strength, and can effectively support the entire circuit board structure and prevent bending damage. The shielding layer 5 is made of conductive cloth (such as nickel-copper composite cloth) for EMI protection, forming a multi-layer printed flexible circuit board. The flexible circuit board passes through the outer shell 601. The dustproof layer 603 on the upper end of the outer shell 601 is made of microporous filter material, which can block dust particles from entering the circuit board while allowing air circulation for heat dissipation. The outer shell 601 is made of aluminum alloy, which is lightweight and sturdy. Its surface is anodized to enhance corrosion resistance. The flexible printed circuit board is pushed into the trapezoidal groove 7 by the connecting strip 801 on the limiting frame 602. The connecting frame 602 is made of PVC plastic. The upper and lower inner walls of the connecting frame 602 contact the substrate 1 and the shielding layer 5, respectively. The connecting rod 803 passes through the connecting frames 602 on both sides and is engaged with the protrusion on the outer wall of the connecting rod 803 by the connecting cap 804. This ensures that the connecting rod 803 is stable and does not loosen. The outer wall of the connecting cap 804 is tightly pressed against the limiting frame 802 to form a reliable mechanical locking structure, thereby further enhancing the stability of the flexible printed circuit board in the connecting frame 602.

[0024] Although the present invention has been illustrated and described with reference to preferred embodiments, those skilled in the art should understand that various changes in form and detail are possible within the scope of the claims.

Claims

1. A multi-layer printed flexible circuit board, comprising a base material (1) and a copper foil (2), the base material (1) is fixedly connected with the copper foil (2) at the upper end, characterized in that: The upper end of the copper foil (2) is fixedly connected to the cover layer (3), the upper end of the cover layer (3) is fixedly connected to the reinforcing plate (4), the upper end of the reinforcing plate (4) is fixedly connected to the shielding layer (5), and the outer wall of the shielding layer (5) is connected to a protective mechanism (6). ​ 2. The multilayer printed flexible circuit board of claim 1, wherein: The protective mechanism (6) includes a shell (601), the inner wall of the shell (601) is movably connected to the shielding layer (5), the upper end of the shell (601) is fixedly connected to the connecting frame (602), and the upper end of the connecting frame (602) is fixedly connected to the dustproof layer (603).

3. The multilayer printed flexible circuit board of claim 2, wherein: The outer shell (601) has a trapezoidal groove (7) machined on its side end, and the outer wall of the trapezoidal groove (7) is connected to a limit mechanism (8).

4. The multilayer printed flexible circuit board of claim 3, wherein: The limiting mechanism (8) includes a connecting strip (801), the outer wall of the connecting strip (801) is slidably connected to the trapezoidal groove (7), the outer wall of the connecting strip (801) is fixedly connected to the limiting frame (802), the outer wall of the limiting frame (802) is movably connected to the connecting rod (803), the outer wall of the protrusion of the connecting rod (803) is engaged with the connecting cap (804), and the outer wall of the connecting cap (804) is pressed against the limiting frame (802).

5. The multilayer printed flexible circuit board of claim 1, wherein: The outer wall of the substrate (1) is fixedly connected to the outer seat (9).

6. The multilayer printed flexible circuit board of claim 2, wherein: The outer casing (601) has an opening (10) machined on its side.

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