Flow choking block of inner layer circuit board

Abstract

The invention discloses a choke block of an inner layer circuit board, which is characterized in that the choke block comprises a plurality of rows of regular hexagon copper blocks arranged on the board edges of unit boards of the inner layer circuit board and board splicing vacancies, the plurality of rows of regular hexagon copper blocks are arranged in a staggered manner, the side length of each regular hexagon copper block is 0.8-1.2 mm, every two adjacent regular hexagon copper blocks are arranged at an interval, and the distance between every two adjacent regular hexagon copper blocks is 0.35-0.4 mm. According to the choke block of the inner layer circuit board, the problems of board explosion and glue flowing caused by low heat dissipation efficiency of the board edge choke block can be effectively improved, and then the quality problem of product white spots is eliminated.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit board manufacturing, and in particular to a flow blocking block of an inner layer circuit board. Background Art

[0002] With the rapid development of the electronics industry, the demand for high-voltage and high-current printed circuit boards in the fields of automobiles, industrial equipment, electronic communications, etc. is increasing, and the application of multi-layer PCB boards is increasing.

[0003] During the production of multi-layer PCB boards, one or more core boards need to be pressed together. During the pressing process, prepreg (mainly epoxy resin) is used to press and thicken the layers. To ensure the overall thickness of the multi-layer board after pressing and the insulation between layers, there are strict requirements for the thickness between layers. During pressing, hot pressing is first performed, and then cold pressing is performed. During hot pressing, the prepreg will melt into liquid at high temperature, and then cold pressing is performed to firmly stick the core board and the outer copper foil together. To prevent the epoxy resin glue from flowing out of the core board area during hot pressing of the prepreg, copper blocks are designed at the edge of the inner circuit board to block the epoxy resin glue from flowing out, so as to avoid quality problems caused by thin layers after cold pressing.

[0004] In the prior art, multiple square baffles are often used to block the inner edge of the board. The design of the square baffle may result in a longer heat transfer path, and heat is easily accumulated during the transfer process, resulting in reduced heat dissipation efficiency. At the same time, the baffle will hinder the air flow, making it impossible to effectively dissipate heat. The obstruction of air flow will lead to poor heat dissipation. Since the coefficient of thermal expansion (CTE) of copper and epoxy resin in the Z direction is very different, it is easy for large copper surface areas to accumulate temperature in strong heat (referring to the integral of temperature over time). If the heat cannot be dissipated, it will cause board explosion and glue flow during the pressing process, and then cause white spot quality problems.

[0005] The purpose of the present invention is to provide a method for designing a flow block of an inner layer circuit board, so as to overcome the technical problems existing in the flow block in the prior art. Summary of the invention

[0006] The technical problem to be solved by the present invention is to provide a baffle block for an inner layer circuit board, which can effectively improve the problems of board bursting and glue flow caused by low heat dissipation efficiency of the baffle block at the edge of the board, thereby eliminating the quality problem of white spots on the product.

[0007] The technical solution of the present invention is as follows:

[0008] A blocking block for an inner circuit board comprises multiple rows of regular hexagonal copper blocks arranged at the edges of unit boards and the empty spaces of the inner circuit board. The multiple rows of regular hexagonal copper blocks are staggered, and the side length of each regular hexagonal copper block is 0.8-1.2 mm. Two adjacent regular hexagonal copper blocks are arranged at intervals, and the spacing is 0.35-0.4 mm.

[0009] Furthermore, there are at least four rows of regular hexagonal copper blocks at the board edges and the empty spaces of the panels.

[0010] Furthermore, the baffle block also includes a copper block in the hollow area laid on the edge of the hollow area of ​​the inner circuit board, and the single side of the copper block in the hollow area is ≥0.5mm.

[0011] Furthermore, the baffle block also includes a process edge copper block laid on the process edge of the inner circuit board, and the single side of the process edge copper block is ≥0.5mm.

[0012] Furthermore, the unit board shape leaves a 2 mm substrate space.

[0013] Compared with the prior art, the baffle block of the inner circuit board provided by the present invention has the following beneficial effects:

[0014] 1. The baffle block of the inner circuit board provided by the present invention is designed with multiple rows of regular hexagonal copper blocks as baffle blocks at the edge of the unit board and the empty space of the puzzle board. The multiple rows of regular hexagonal copper blocks are staggered, and two adjacent regular hexagonal copper blocks are spaced apart, with a spacing of 0.35-0.4mm. The gap between the copper blocks serves as a guide groove, and the overflowing colloid can be guided through the gap between the regular hexagonal copper blocks. In the present invention, a regular hexagonal baffle block design is adopted to change the flow path and velocity distribution of the fluid, thereby affecting the resistance of the fluid. When the fluid flows through the regular hexagonal structure, the flow of the fluid will be hindered by the edge of the hexagon, slowing down the flow rate, thereby increasing the resistance of the fluid.

[0015] Compared with the square baffles in the prior art, the regular hexagonal design has its unique performance in terms of fluid resistance, as follows: the square or rectangular baffle design may cause the fluid to generate eddies and turbulence at the corners, greatly increasing the fluid resistance; while the regular hexagonal baffle design in the present invention makes the fluid flow path smoother and significantly reduces the resistance.

[0016] Therefore, the baffle block of the inner circuit board provided by the present invention optimizes the flow path of the fluid through reasonable design, reduces fluid resistance, improves the heat dissipation effect, and effectively improves the problems of board bursting and glue flow caused by low heat dissipation efficiency of the baffle block at the edge of the board, thereby eliminating the quality problem of white spots in the product.

[0017] 2. The baffle block of the inner circuit board provided by the present invention has a 2mm substrate space left in the unit board shape, which can be used for riveting or hot-melt fixing before the circuit board is pressed together. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0019] Figure 1 It is a schematic diagram of a flow blocking block of an inner circuit board of the present invention;

[0020] Figure 2 This is a schematic diagram of the inner layer circuit board. DETAILED DESCRIPTION

[0021] In order to enable those skilled in the art to better understand the technical solutions in the embodiments of the present invention and to make the above-mentioned objects, features and advantages of the present invention more obvious and understandable, the specific implementation modes of the present invention are further described below.

[0022] It should be noted that the description of these embodiments is used to help understand the present invention, but does not constitute a limitation of the present invention. In addition, the technical features involved in each embodiment of the present invention described below can be combined with each other as long as there is no conflict between them.

[0023] Please refer to Figure 1 and Figure 2 ,in Figure 1 is a schematic diagram of a flow blocking block of an inner circuit board of the present invention, Figure 2 It is a schematic diagram of an inner circuit board. A flow block of an inner circuit board includes multiple rows of regular hexagonal copper blocks 1 arranged at the edge of the unit board and the empty space of the assembly board of the inner circuit board. The multiple rows of regular hexagonal copper blocks are staggered, and the side length of each regular hexagonal copper block is 0.8-1.2mm. Two adjacent regular hexagonal copper blocks are arranged at intervals, and the spacing is 0.35-0.4mm. The thickness of the copper block is adjusted according to the thickness of the bottom copper of the inner core board.

[0024] Two adjacent regular hexagonal copper blocks are arranged at intervals, and the gap serves as a guide groove 2, so that the filler can flow along the guide groove. By rationally designing multiple rows of regular hexagonal copper blocks, the flow path of the fluid is optimized. Compared with square baffles, the fluid resistance can be reduced, the heat dissipation effect is improved, and the problems of board bursting and glue flow caused by low heat dissipation efficiency of the board edge baffles are effectively improved, thereby eliminating the quality problem of white spots in the product.

[0025] Preferably, the side length of the regular hexagonal copper block is 1 mm, and the distance between two adjacent regular hexagonal copper blocks is 0.38 mm. More preferably, the regular hexagonal copper blocks at the board edge and the empty space of the panel are at least four rows.

[0026] As a further preferred solution, the baffle block also includes a copper block 3 in the hollow area laid on the edge of the hollow area of ​​the inner circuit board, and the single side of the copper block in the hollow area is ≥ 0.5mm. Since the pressing is to fill the etched inner circuit with the epoxy resin glue in the semi-cured sheet, and then form a whole with the outer copper foil, the purpose of copper laying in the hollow area is to reduce the filling of epoxy resin glue, which will not affect the thickness of the layer after cold pressing, and prevent quality problems such as white spots and voids caused by lack of glue.

[0027] As a further preferred solution, the flow block also includes a process edge copper block 4 laid on the process edge of the inner circuit board, and the single side of the process edge copper block is ≥0.5mm. The function of the process edge copper is the same as that of the gong blank area copper.

[0028] As a further preferred solution, the unit board has 2mm of substrate space outside, which can be used for riveting or hot-melt fixing before the circuit board is pressed together. The flow block of the inner circuit board provided by the present invention effectively reduces the fluid resistance and improves the heat dissipation effect by designing multiple rows of regular hexagonal copper blocks on the edge of the board as flow blocks, effectively improving the problems of board explosion and glue flow caused by low heat dissipation efficiency of the flow block on the edge of the board, thereby eliminating the quality problem of white spots on the product.

[0029] The embodiments of the present invention are described in detail above, but the present invention is not limited to the described embodiments. For those skilled in the art, various changes, modifications, substitutions and variations made to these embodiments without departing from the principles and spirit of the present invention are still within the protection scope of the present invention.

Claims

1. A flow block for an inner layer circuit board, characterized in that: It includes multiple rows of regular hexagonal copper blocks arranged on the edge of the unit board and the empty space of the assembly board of the inner circuit board. The multiple rows of regular hexagonal copper blocks are staggered, and the side length of each regular hexagonal copper block is 0.8-1.2mm. Two adjacent regular hexagonal copper blocks are arranged at intervals, and the spacing is 0.35-0.4mm.

2. The blocking block of the inner layer circuit board according to claim 1, characterized in that: There are at least four rows of regular hexagonal copper blocks on the edges of the board and in the empty spaces of the panels.

3. The blocking block of the inner circuit board according to claim 1, characterized in that: The baffle block also includes a copper block in the hollow area laid on the edge of the hollow area of ​​the inner circuit board, and the single side of the copper block in the hollow area is ≥0.5mm.

4. The blocking block of the inner circuit board according to claim 1, characterized in that: The blocking block also includes a process edge copper block laid on the process edge of the inner circuit board, and the single side of the process edge copper block is ≥0.5mm.

5. The blocking block of the inner circuit board according to claim 1, characterized in that: The unit board shape leaves 2mm of substrate space.

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