Circuit board and gas meter

Abstract

The utility model relates to circuit board protection technical field especially relates to a kind of circuit board and gas meter.Circuit board includes main body board, protective layer and adhesive layer, and the upper end surface of main body board is equipped with component at least.The protective layer covers the upper end surface of main body board, and the protective layer is equipped with the hole and / or the avoidance slot of corresponding adaptation with component one by one, and the hole penetrates the both ends of protective layer thickness direction.Adhesive layer is located between the upper end surface of main body board and protective layer, and the protective layer is adhered to the upper end surface of main body board by adhesive layer.Gas meter includes the above-mentioned circuit board, and the protective layer in circuit board is connected by adhesive layer adhering with main body board, so that the assembly of circuit board is simple and easy to operate, improves assembly efficiency, and reduces the protection cost of circuit board.At the same time, it is convenient to tear off the protective layer from the main body board, realizes the quick disassembly of protective layer, and reduces the maintenance difficulty of circuit board.

Description

Technical Field

[0001] This utility model relates to the field of circuit board protection technology, and in particular to a circuit board and a gas meter. Background Technology

[0002] Existing gas meters typically use UV adhesive coating technology to form a UV adhesive layer on the circuit board surface for protection on their internal circuit boards. The problems with this protective structure are: the process is complex, requiring multiple steps such as dispensing and UV curing, which is time-consuming (approximately 5-10 minutes per circuit board). It also requires high precision in dispensing and a suitable curing environment, increasing the cost of protecting the circuit board. Furthermore, the UV adhesive layer has high hardness after curing, necessitating mechanical scraping or solvent dissolution during circuit board repair, which can easily damage the circuit board and its components, increasing the difficulty of repair. Utility Model Content

[0003] One objective of this invention is to provide a circuit board that reduces the protection cost and maintenance difficulty of the circuit board.

[0004] Another objective of this invention is to provide a gas meter that reduces the protection cost and maintenance difficulty of the circuit board.

[0005] To achieve this objective, the technical solution adopted by this utility model is as follows:

[0006] Circuit board, including:

[0007] The main body plate has at least one component mounted on its upper surface;

[0008] A protective layer is provided, which covers the upper surface of the main body plate. The protective layer has clearance holes and / or clearance grooves that correspond to and are adapted to the components. The clearance holes penetrate through both ends of the protective layer in the thickness direction.

[0009] An adhesive layer is located between the upper surface of the main body panel and the protective layer, and the protective layer is bonded to the upper surface of the main body panel through the adhesive layer.

[0010] As an alternative to the circuit board, along the thickness direction of the main board, the projection of the protective layer onto the main board falls entirely within the upper surface of the main board.

[0011] As an optional circuit board, the distance between the multiple circumferential sides of the protective layer projected onto the main board and the corresponding circumferential sides of the upper end surface is 1mm to 2mm.

[0012] As an optional circuit board solution, the gap between the inner wall of the clearance hole and the circumferential sidewall corresponding to the adapted component is 0.5mm to 2mm.

[0013] As an optional circuit board, the depth of the clearance groove is H1, and the height of the component that is adapted to the clearance groove is H2, then 1.2H2≤H1≤1.5H2.

[0014] As an optional circuit board, the thickness of the protective layer is 1mm to 5mm.

[0015] As an optional solution for the circuit board, the Shore hardness of the protective layer is less than or equal to 35 degrees.

[0016] As an optional solution for the circuit board, the protective layer is a foam layer or a silicone layer.

[0017] As an optional solution for the circuit board, the adhesive layer is made of one of the following materials: pressure-sensitive adhesive, silicone adhesive, acrylic adhesive, epoxy resin adhesive, silicone acrylic adhesive, and phenolic resin adhesive.

[0018] Gas meter, including the aforementioned circuit board.

[0019] The beneficial effects of this utility model are as follows:

[0020] The circuit board proposed in this utility model includes a main board, a protective layer, and an adhesive layer. The protective layer covers the upper surface of the main board and is bonded to it via the adhesive layer. Components on the upper surface of the main board are housed in corresponding clearance holes and / or clearance grooves to protect them. Because the protective layer is bonded to the main board via the adhesive layer, the circuit board assembly is simple and easy, improving assembly efficiency and reducing the protection cost. Simultaneously, the protective layer can be easily removed from the main board, enabling quick disassembly and reassembly of the protective layer and reducing the difficulty of circuit board repair.

[0021] The gas meter proposed in this utility model includes the aforementioned circuit board. The protective layer of the circuit board is bonded to the main board with an adhesive layer, making the assembly of the circuit board simple and easy, improving assembly efficiency, and reducing the protection cost of the circuit board. At the same time, it is easy to remove the protective layer from the main board, realizing quick disassembly and assembly of the protective layer and reducing the difficulty of circuit board maintenance. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the main plate provided in this embodiment of the utility model;

[0023] Figure 2 This is a schematic diagram of the structure of the protective layer provided in an embodiment of this utility model;

[0024] Figure 3 This is a cross-sectional view of the circuit board provided in an embodiment of this utility model.

[0025] The component names and labels in the diagram are as follows:

[0026] 1. Main board; 11. Components; 12. Wiring harness; 2. Protective layer; 21. Clearance hole; 22. Clearance groove; 3. Adhesive layer. Detailed Implementation

[0027] To make the technical problem solved by this utility model, the technical solution adopted, and the technical effect achieved clearer, the technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are merely for explaining this utility model and not for limiting it. Furthermore, it should be noted that, for ease of description, only the parts related to this utility model are shown in the accompanying drawings, not all of them.

[0028] In the description of this utility model, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this utility model based on the specific circumstances.

[0029] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0030] In the description of this embodiment, the terms "upper," "lower," "right," and "left," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, 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. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0031] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0032] This embodiment presents a gas meter, an instrument used to measure gas consumption, widely used in homes, businesses, and industrial settings. By recording the amount of gas flowing through it, the gas meter helps users understand their gas usage and serves as a basis for billing.

[0033] like Figure 1 As shown, the gas meter includes a circuit board, which includes a main board 1. Various components 11, such as heat sinks and connectors, are mounted on the main board 1 by means of through-hole mounting, surface mounting, or soldering. The connectors have wire harnesses 12 for electrical connection with external devices. Since the circuit board is existing technology, its composition will not be described in detail.

[0034] Existing gas meters typically use UV adhesive coating technology to form a UV adhesive layer on the surface of the main board for protection on their internal circuit boards. This protective structure is complex, requiring multiple processes such as dispensing and UV curing, which is time-consuming and demands high precision in dispensing and a suitable curing environment, increasing the cost of protecting the circuit board. Moreover, the UV adhesive layer has high hardness after curing, requiring mechanical scraping or solvent dissolution during circuit board repair, which can easily damage the circuit board and the components mounted on it, increasing the difficulty of circuit board repair.

[0035] To solve the above problems, such as Figure 2 and Figure 3 As shown, this embodiment also proposes a circuit board, which includes a main board 1, a protective layer 2, and an adhesive layer 3. At least one component 11 is mounted on the upper surface of the main board 1. The protective layer 2 covers the upper surface of the main board 1 and has corresponding clearance holes 21 and / or clearance grooves 22 that fit each component 11. The clearance holes 21 penetrate both ends of the protective layer 2 in the thickness direction (vertical direction in the figure). The adhesive layer 3 is located between the upper surface of the main board 1 and the protective layer 2, and the protective layer 2 is bonded to the upper surface of the main board 1 through the adhesive layer 3. The components 11 on the upper surface of the main board 1 are accommodated one-to-one in the corresponding clearance holes 21 and / or clearance grooves 22 to protect the components 11. Because the protective layer 2 is bonded to the main board 1 via the adhesive layer 3, the assembly of the circuit board is simple and easy, improving assembly efficiency and reducing the protection cost of the circuit board. At the same time, it is easy to remove the protective layer 2 from the main board 1, enabling quick disassembly and reassembly of the protective layer 2 and reducing the difficulty of circuit board repair.

[0036] It should be noted that the aforementioned clearance hole 21 is a hollow structure of the protective layer 2, designed to avoid critical parts such as solder points, test points, and connectors on the main board 1. The clearance groove 22 surrounds other pin-type components 11 (such as capacitors and resistors), forming a wrap-around protection.

[0037] like Figure 3 As shown, along the thickness direction of the main body plate 1 (vertical direction in the figure), the projection of the protective layer 2 onto the main body plate 1 falls entirely within the upper surface of the main body plate 1. Since both the main body plate 1 and the protective layer 2 are rectangular structures, the size of the protective layer 2 can be proportionally reduced from that of the main body plate 1, making the length and width of the protective layer 2 slightly smaller than those of the main body plate 1. This ensures that the circumferential edge of the protective layer 2 forms a complete circumferential seal with the upper surface of the main body plate 1, preventing external moisture from seeping into the center of the upper surface of the main body plate 1 from the edge of the protective layer 2, thus ensuring the dryness and cleanliness of the component 11 and further improving the protection of the component 11.

[0038] In an optional embodiment, the distance between the multiple circumferential sides of the protective layer 2 projected onto the main body plate 1 and the corresponding circumferential sides of the upper end face is 1mm to 2mm. The aforementioned distance can be 1mm, 1.2mm, 1.4mm, 1.6mm, 1.8mm, or 2mm, etc., so that a certain distance is maintained between the circumferential edge of the protective layer 2 and the edge of the corresponding upper end face of the main body plate 1. This ensures that even if irregular circumferential edges occur during die-cutting, a full circumferential seal is formed between the circumferential edge of the protective layer 2 and the upper end face of the main body plate 1.

[0039] like Figure 1 and Figure 2 As shown, the main body plate 1 has components 11 (connectors, etc.) with wire harnesses 12 inserted into it, as well as other components 11 fixed to the main body plate 1 by welding or other means. The protective layer 2 is pre-formed according to the size of the main body plate 1, the size of the components 11, and the installation position, through a die-cutting process. Then, an adhesive layer 3 with a release film is coated on the bottom surface of the protective layer 2. Finally, the release film is removed, and the protective layer 2 is aligned with the upper surface of the main body plate 1 and pasted. A specified pressure is applied by a roller pressing device to ensure that there are no air bubbles between the protective layer 2 and the main body plate 1 after bonding, so as to ensure good bonding quality.

[0040] like Figure 3 As shown, the gap between the inner wall of the clearance hole 21 and the corresponding circumferential sidewall of the adapted component 11 is 0.5mm to 2mm. In this embodiment, the gap L1 can be 0.5mm, 0.8mm, 1mm, 1.2mm, 1.5mm, 1.8mm, or 2mm, etc., to ensure that the component 11 with the wire harness 12 can pass smoothly through the clearance hole 21, avoiding interference or compression between the protective layer 2 and the component 11 with the wire harness 12, and ensuring a stable and reliable electrical connection between the component 11 and the main board 1. If the gap L1 is too large, the exposed area of ​​the main board 1 will increase, which is not conducive to the protection of the main board 1.

[0041] like Figure 3As shown, the depth of the clearance groove 22 is H1, and the height of the component 11 that is adapted to the clearance groove 22 is H2. Therefore, 1.2H2≤H1≤1.5H2. Through the above settings, the depth of the clearance groove 22 is 1.2 to 1.5 times the height of the component 11 contained in the clearance groove 22, which avoids the inner top wall of the clearance groove 22 from squeezing the component 11, thus improving the protection of the component 11. At the same time, it avoids the clearance groove 22 being too deep, which would cause the thickness of the protective layer 2 to increase excessively.

[0042] In an optional embodiment, the thickness of the protective layer 2 is 1mm to 5mm. In this embodiment, the thickness H3 can be 1mm, 2mm, 3mm, 4mm or 5mm, etc. Through the above settings, not only can the clearance groove 22 have sufficient groove depth to protect the component 11, but it also avoids the problem of increased cost and excessive overall thickness of the circuit board caused by excessive thickness of the protective layer 2. This helps to reduce the installation space occupied by the circuit board and ensures the compact installation of the circuit board.

[0043] In an optional embodiment, the Shore hardness of the protective layer 2 is less than or equal to 35 degrees, so that the protective layer 2 is relatively soft, avoiding damage to the component 11 during bonding or use, and further improving the protection of the component 11.

[0044] In an optional embodiment, the protective layer 2 is a foam layer or a silicone layer. If the material of the protective layer 2 is foam, a density of 0.4 g / cm³ can be selected. 3 ~0.8g / cm 3 The protective layer 2 is made of EPDM or PU foam with a closed-cell rate of ≥95%, effectively isolating water and gas, and passing the IP65 waterproof test without penetration. Furthermore, the foam layer possesses physical properties such as tear strength ≥5N / mm and tensile strength ≥0.5MPa, which not only improves the structural strength of the foam layer but also provides mechanical protection from the closed-cell foam, absorbing the vibration and impact energy received by the circuit board, reducing the vibration stress on component 11, and acting as an environmental barrier, thus enhancing the protection of component 11. In this embodiment, the protective layer 2 can be EPDM foam treated with UV resistance and oil resistance, meeting the temperature resistance range of -40℃ to 120℃, and having a water absorption rate of <0.1%.

[0045] In optional embodiments, the adhesive layer 3 is made of one of the following: pressure-sensitive adhesive, silicone adhesive, acrylic adhesive, epoxy resin adhesive, silicone acrylic adhesive, and phenolic resin adhesive. In this embodiment, the adhesive layer 3 is an acrylic pressure-sensitive adhesive or a silicone pressure-sensitive adhesive. The thickness of the adhesive layer 3 is 0.1mm to 0.3mm, with an initial tack of not less than 10N / 25mm and a holding power of not less than 24 hours (at 80°C), to achieve a peelable bond between the protective layer 2 and the main board 1. Through the above settings, no adhesive residue is left when the protective layer 2 is removed from the main board 1, ensuring that the surface cleanliness of the upper surface of the main board 1 after repair is not less than 98%. For example, the adhesive layer 3 can be a 0.2mm thick acrylic pressure-sensitive adhesive that complies with RoHS environmental standards and has an initial peel strength of not less than 15N / 25mm.

[0046] The above embodiments merely illustrate the basic principles and characteristics of this utility model. This utility model is not limited to the above embodiments. Various changes and modifications can be made to this utility model without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed utility model. The scope of protection of this utility model is defined by the appended claims and their equivalents.

Claims

1. A circuit board, characterized by, include: The main body plate (1) has at least one component (11) mounted on its upper surface; A protective layer (2) is provided, which covers the upper surface of the main body plate (1). The protective layer (2) has clearance holes (21) and / or clearance grooves (22) that correspond to and are adapted to the components (11). The clearance holes (21) penetrate both ends of the protective layer (2) in the thickness direction. The adhesive layer (3) is located between the upper surface of the main body plate (1) and the protective layer (2), and the protective layer (2) is bonded to the upper surface of the main body plate (1) through the adhesive layer (3).

2. The circuit board of claim 1, wherein Along the thickness direction of the main body plate (1), the projection of the protective layer (2) onto the main body plate (1) falls entirely within the upper surface of the main body plate (1).

3. The circuit board of claim 2, wherein, The distance between the multiple circumferential sides of the protective layer (2) projected onto the main body plate (1) and the corresponding circumferential sides of the upper end surface is 1mm to 2mm.

4. The circuit board of claim 1, wherein The gap between the inner wall of the clearance hole (21) and the corresponding circumferential sidewall of the adapted component (11) is 0.5mm to 2mm.

5. The circuit board of claim 1, wherein, The depth of the clearance groove (22) is H1, and the height of the component (11) that is adapted to the clearance groove (22) is H2, then 1.2H2≤H1≤1.5H2.

6. The circuit board according to any one of claims 1 to 5, characterized by The thickness of the protective layer (2) is 1mm to 5mm.

7. The circuit board according to any one of claims 1 to 5, characterized by The Shore hardness of the protective layer (2) is less than or equal to 35 degrees.

8. The circuit board according to any one of claims 1 to 5, characterized by The protective layer (2) is a foam layer or a silicone layer.

9. The circuit board according to any one of claims 1 to 5, characterized by The adhesive layer (3) is made of one of the following: pressure-sensitive adhesive, silicone adhesive, acrylic adhesive, epoxy resin adhesive, silicone acrylic adhesive, and phenolic resin adhesive.

10. A gas meter characterised in that, The circuit board includes any one of claims 1 to 9.

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