A digital tube assembly structure and its assembly method

Abstract

The present invention discloses a digital tube assembly structure and an assembly method thereof. The method includes: printing matte ink on the front surface of a circuit board to form a matte ink layer; soldering a wick onto the circuit board through a pad; drilling exhaust holes at positions below each wick on the circuit board; soaking the circuit board in an acetone solution to form an acetone layer on the matte ink layer, and the acetone solution can penetrate into the gap area between the wick and the circuit board; initially installing the circuit board in a plastic shell through epoxy resin, and performing a high-temperature curing operation on the epoxy resin. During the high-temperature curing process, the acetone layer volatilizes due to heat, and the volatilized acetone takes the bubbles near the wick out through the exhaust holes. The present invention can take out the bubbles generated during the encapsulation process through the volatilization of acetone, preventing the bubbles from affecting the use effect of the digital tube, not only greatly reducing the defective rejection rate, reducing the production cost, but also improving the display effect of the digital tube and enhancing the product performance.

Description

Technical Field

[0001] The present invention belongs to the field of digital tube production, relates to digital tube assembly technology, and specifically relates to a digital tube assembly structure and an assembly method thereof. Background Art

[0002] With the increasing application fields and scopes of digital tubes, the market has higher and higher requirements for the display performance of digital tubes. The core components of digital tubes include a plastic shell and a circuit board (PCB). The windows on the plastic shell are lit by the lamp wicks on the circuit board to achieve the digital display function.

[0003] As Figure 1 shown, the existing digital tube includes a plastic shell 1, a circuit board 2, and several lamp wicks 3. Each lamp wick 3 is welded to the circuit board 2 through two solder pads 4. This makes there be a gap between the lamp wick 3 and the circuit board 2. During the assembly process of the digital tube, the circuit board 2 needs to be encapsulated into the plastic shell 1. The existing encapsulation method is achieved through epoxy resin. During the encapsulation process, since the epoxy resin used for encapsulation has a certain viscosity, the epoxy resin cannot flow into the gap under the lamp wick 3. This makes dark bubbles form between the lamp wick 3 and the circuit board 2. When the epoxy resin is cured at high temperature, the bubbles expand due to heat and escape. These bubbles are usually distributed near the lamp wick 3, which will cause uneven light emission of the lamp wick 3, seriously affecting the display effect of the digital tube, and also easily causing defective waste of the digital tube, increasing the production cost. Summary of the Invention

[0004] Object of the Invention: In order to overcome the deficiencies in the prior art, the present invention provides a digital tube assembly structure and an assembly method thereof, which can bring out the bubbles generated during the encapsulation process through the volatilization of acetone, preventing the bubbles from affecting the use effect of the digital tube. It not only greatly reduces the defective waste rate, reduces the production cost, but also improves the display effect of the digital tube and enhances the product performance.

[0005] Technical Solution: To achieve the above object, the present invention provides a digital tube assembly structure, including a plastic shell, a circuit board, and several lamp wicks. The lamp wicks are welded to the circuit board through two solder pads. There is a gap between the lamp wicks and the circuit board. The circuit board is encapsulated in the plastic shell through epoxy resin. A matte ink layer is provided on the front surface of the circuit board. An acetone layer is provided on the matte ink layer. Exhaust holes are provided on the circuit board at the positions below the lamp wicks.

[0006] Further, the matte ink layer is printed on the front surface of the circuit board.

[0007] Further, the exhaust holes are coaxially arranged with the lamp wicks.

[0008] The present invention provides an assembly method for a digital tube assembly structure, comprising the following steps:

[0009] S1: Print matte ink on the front side of the circuit board to form a matte ink layer;

[0010] S2: Solder the wick to the circuit board through the solder pad;

[0011] S3: Drill holes below each wick on the circuit board to form exhaust holes;

[0012] S4: Immerse the circuit board in an acetone solution. The acetone solution uniformly distributes and accumulates on the matte ink layer to form an acetone layer, and the acetone solution can penetrate into the gap area between the wick and the circuit board;

[0013] S5: Initially install the circuit board in the plastic shell through epoxy resin, and perform a high-temperature curing operation on the epoxy resin. During the high-temperature curing process, the acetone layer volatilizes when heated, and the volatilized acetone brings out the bubbles near the wick from the exhaust holes;

[0014] S6: After the high-temperature curing operation is completed, the circuit board is encapsulated in the plastic shell.

[0015] The design principle of the present invention is as follows: Due to the special properties of the matte ink, liquid acetone can adhere to the matte ink and be evenly distributed. Also, because of the low viscosity and good fluidity of acetone, acetone can penetrate into the gaps between the wick and the circuit board and be evenly distributed. Moreover, due to the volatile property of acetone, its volatilization temperature can match the curing temperature of epoxy resin (60 - 80 °C), enabling acetone to volatilize during the curing process of epoxy resin. The volatilization of acetone can bring out the bubbles near the wick from the exhaust holes, thus completely solving the bubble problem.

[0016] Beneficial effects: Compared with the prior art, the present invention can bring out the bubbles generated during the encapsulation process through the volatilization of acetone, preventing the bubbles from affecting the use effect of the digital tube. It not only significantly reduces the defective rejection rate, lowers the production cost, but also improves the display effect of the digital tube and enhances the product performance. Description of the Drawings

[0017] Figure 1 It is an assembly schematic diagram of an existing digital tube;

[0018] Figure 2 It is a structural schematic diagram of the circuit board in the present invention;

[0019] Figure 3 It is a planar cross-sectional view of the wick on the circuit board in the present invention. Detailed Embodiments

[0020] The present invention will be further clarified below in conjunction with the accompanying drawings and specific embodiments. It should be understood that these embodiments are only used to illustrate the present invention and not to limit the scope of the present invention. After reading the present invention, various equivalent modifications made by those skilled in the art to the present invention fall within the scope defined by the appended claims of this application.

[0021] As Figures 1 to 3 shown, the present invention provides a digital tube assembly structure, including a plastic shell 1, a circuit board 2, and a plurality of lamp cores 3. Each lamp core 3 is welded to the circuit board 2 through two solder pads 4, and there is a gap between the lamp core 3 and the circuit board 2. A matte ink layer 6 is printed on the front side of the circuit board 2, and an acetone layer 7 is provided on the matte ink layer 6. An exhaust hole 5 is provided on the circuit board 2 below the lamp core 3, and the exhaust hole 5 and the lamp core 3 are coaxially arranged.

[0022] In this embodiment, it is necessary to encapsulate the circuit board 2 in the plastic shell 1 with epoxy resin, and an assembly method of a digital tube assembly structure is provided, which specifically includes the following steps:

[0023] S1: Print matte ink on the front side of the circuit board 2 to form a matte ink layer 6;

[0024] S2: Weld each lamp core 3 to the designated position on the circuit board 2 through two solder pads 4;

[0025] S3: Drill holes below each lamp core 3 on the circuit board 2 to form exhaust holes 5;

[0026] S4: Immerse the circuit board 2 in an acetone solution. After soaking for 10 seconds, due to the mutual matching characteristics of the matte ink and acetone, the acetone solution can be evenly distributed on the matte ink layer 6, accumulate to form acetone 7, and the acetone solution can penetrate into the gap area between the lamp core 3 and the circuit board 2, specifically as Figure 2 shown;

[0027] S5: Enter the circuit board 2 from the bottom of the plastic shell 1 from bottom to top with the front side facing up into the plastic shell 1, and initially install the circuit board 2 in the plastic shell 1 with epoxy resin. Due to the relatively high viscosity of the epoxy resin, it cannot flow into the gap space between the lamp core 3 and the circuit board 2, so dark bubbles will be formed in the gap space between the lamp core 3 and the circuit board 2;

[0028] S6: Place the plastic shell 1 in a high-temperature curing chamber to perform high-temperature curing operation on the epoxy resin. The curing temperature is 60 - 80 °C. During the high-temperature curing process, the dark bubbles formed in step S5 expand due to heat and will escape from the gap space. These bubbles will be distributed near the lamp core 3;

[0029] During the high-temperature curing process, the acetone layer 7 volatilizes due to heat, and the volatilized acetone brings out the bubbles near the lamp core 3 from the exhaust hole 5;

[0030] S7: After the high-temperature curing operation is completed, the circuit board 2 is encapsulated in the plastic shell 1.

[0031] When the circuit board 2 is initially installed in the plastic shell 1 through epoxy resin in step S5 of this embodiment, since the circuit board 2 is manually placed in the plastic shell 1, there are errors in both the angle and position accuracy. Once the error is relatively large, dark bubbles will also be generated at the edges of the circuit board 2 and the plastic shell 1. However, after step S6, these bubbles will also be carried out by the volatilized acetone, ensuring that there are no bubbles on the encapsulated circuit board 2.

[0032] It should also be noted in this embodiment that the implementation difficulties and innovations of the above solution include the following points:

[0033] 1. How to stably distribute the liquid acetone on the circuit board 2.

[0034] 2. Since the curing temperature of the epoxy resin itself is not very high, how to enable other substances to volatilize during the curing process.

[0035] 3. How to achieve exhaust after volatilization.

[0036] 4. During the existing high-temperature curing process, the plastic shell 1 is inverted and the front side of the circuit board 2 is facing down.

[0037] Therefore, based on the above three difficulties, the solution of this embodiment cannot be equivalently achieved by conventional means. In the present invention, through the combined use of the matte ink layer 6, acetone 7 and the exhaust hole 5, the above difficulties are solved, and the performance of the finally assembled digital tube is substantially improved.

Claims

1. An assembly method for a digital tube assembly structure, characterized in that, It includes the following steps: S1: Print matte ink on the front side of the circuit board to form a matte ink layer; S2: Solder the wick to the circuit board through the pad; S3: Drill holes below each wick on the circuit board to form exhaust holes; S4: Immerse the circuit board in the acetone solution. The acetone solution uniformly distributes and accumulates on the matte ink layer to form an acetone layer, and the acetone solution can penetrate into the gap area between the wick and the circuit board; S5: Initially install the circuit board in the plastic shell through epoxy resin, and perform high-temperature curing operation on the epoxy resin. During the high-temperature curing process, the acetone layer volatilizes when heated, and the volatilized acetone takes out the bubbles near the wick from the exhaust holes; S6: After the high-temperature curing operation is completed, the encapsulation of the circuit board in the plastic shell is achieved.

2. The assembling method of a digital tube assembling structure according to claim 1, characterized in that, In step S3, the exhaust holes and the wicks are coaxially arranged.

3. The assembling method of a digital tube assembling structure according to claim 1, characterized in that, In step S5, the temperature of the high-temperature curing is 60~80°C.

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