Preparation method of positioning hole of circuit board

Abstract

The preparation method of the positioning hole of the circuit board comprises the following steps that a conducting layer of a circuit substrate is prepared into a circuit layer, the circuit layer comprises a circuit part and a marking part, an annular gap is formed between the adjacent marking part and circuit part when observed relative to the circuit layer, and the marking part is provided with an etching gap; the etching gap and the annular gap are coaxially arranged; identifying an image of the etched void; and drilling the marking part according to the central coordinate of the image so as to form a positioning hole which is located in a region range limited by the annular gap. The preparation method provided by the invention has a hole position correction function, so that the relative position between the positioning hole and the circuit part does not deviate due to expansion and contraction of the circuit substrate, thereby being beneficial to improving the positioning precision of the circuit board and improving the forming quality of the circuit board. In addition, the preparation method provided by the invention is simple in steps, and is also beneficial to improving the production efficiency and reducing the preparation cost.

Description

Technical Field

[0001] This invention relates to the technical field of circuit boards, and more specifically to a method for preparing positioning holes for circuit boards. Background Technology

[0002] In the field of circuit board manufacturing, existing hole-forming methods typically involve drilling holes in a circuit substrate according to pre-set drilling coordinates, followed by forming the circuit layer through at least three steps: film coating, exposure and development, and etching. However, circuit substrates may expand or shrink during transportation or forming. Therefore, using pre-set drilling coordinates and existing photomasks can easily lead to deviations between the positioning holes and the circuit layer, which can affect the punching and positioning accuracy of the subsequent circuit board and may also affect the forming quality of the circuit board. Summary of the Invention

[0003] To overcome the shortcomings of existing technologies, the present invention aims to provide a method for preparing positioning holes on a circuit board. This method features hole position correction, ensuring that the relative position between the positioning holes and the circuit board remains unchanged despite expansion and contraction of the circuit board substrate. This improves the positioning accuracy and molding quality of the circuit board. Furthermore, the method is simplified, which also improves production efficiency and reduces manufacturing costs.

[0004] To solve the above problems, the technical solution adopted by the present invention is as follows: A method for preparing positioning holes on a circuit board includes the following steps: The conductive layer of the circuit substrate is fabricated into a circuit layer, the circuit layer including a circuit portion and a marking portion. When viewed relative to the circuit layer, there is an annular gap between adjacent marking portions and circuit portions, and the marking portion has an etched gap. The etched gap and the annular gap are coaxially arranged. Image identifying the etched gaps; The marking portion is drilled according to the center coordinates of the image to form a positioning hole, which is located within the area defined by the annular gap.

[0005] In some possible implementations, the annular gap includes a gap ring and at least two gap grooves, the gap grooves communicating with the gap ring and extending toward the center of the marking portion, and at least two of the gap grooves being spaced apart around the center of the marking portion; During the drilling process, the positioning hole is isolated from the gap ring and the gap groove.

[0006] In some possible implementations, the number of the gap grooves is four, and each pair of gap grooves is symmetrically arranged relative to the center position of the marking portion.

[0007] In some possible implementations, the following steps are also included: The quality of the circuit board opening is evaluated based on the distance between the positioning hole and each of the gap slots. If the positioning hole and each of the gap slots are separated, the opening is qualified. If the positioning hole and one of the gap slots are connected, the opening is unqualified.

[0008] In some possible implementations, the gap ring is circular in shape.

[0009] In some possible implementations, the cross-section of the gap groove is square.

[0010] In some possible implementations, the gaps are spaced at equal intervals between every two circumferentially adjacent gaps.

[0011] Compared with the prior art, the beneficial effects of the present invention are as follows: In this application, after the conductive layer of the circuit board is fabricated into a circuit layer to form a circuit board, etched gaps are pre-formed in the marked areas of the circuit layer. The image of the etched gaps is then identified, and holes are drilled in the marked areas based on the center coordinates of the image. Therefore, even if the circuit board expands or contracts, the drilling position in this application is at a preset position outside the corresponding circuit area. That is, the solution in this application has a corrective function, ensuring that the relative position between the positioning hole and the circuit area will not deviate due to the expansion or contraction of the circuit board. This improves the positioning accuracy of the circuit board and enhances its forming quality. Furthermore, the fabrication method of this application is simplified, which also helps to improve production efficiency and reduce manufacturing costs.

[0012] The present invention will now be described in further detail with reference to the accompanying drawings and specific embodiments. Attached Figure Description

[0013] Figure 1 A flowchart illustrating a method for preparing positioning holes on a circuit board, as provided in one embodiment; Figure 2 A top view of a circuit board with etched gaps provided in one embodiment; Figure 3 This is a top view of a circuit board with positioning holes.

[0014] Explanation of reference numerals in the attached figures: 10 - Circuit section; 20 - Marking section; 2010 - Etching gap; 201 - Positioning hole; 30 - Annular gap; 301 - Gap ring; 302 - Gap groove. Detailed Implementation

[0015] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0016] The terms "first," "second," etc., in the specification, claims, and accompanying drawings of this application are constructed to distinguish different objects, not to describe a particular order. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion. It should be noted that when an element is referred to as "fixed to" another element, it can be directly on the other element or there may be an intervening element. When an element is referred to as "connected to" another element, it can be directly connected to the other element or there may be an intervening element. The accompanying drawings only depict the stacking relationship between different layers and do not limit their thickness relationships.

[0017] Reference Figure 1 , Figure 2 and Figure 3 One embodiment of this application provides a method for preparing positioning holes on a circuit board, comprising the following steps.

[0018] Step S101: The conductive layer of the circuit substrate is fabricated into a circuit layer. The circuit layer includes a line portion 10 and a marking portion 20. Viewed relative to the circuit layer, an annular gap 30 exists between adjacent marking portions 20 and line portions 10, and the marking portions 20 have etched gaps 2010. The etched gaps 2010 and the annular gap 30 are coaxially arranged. The specific operation of fabricating the conductive layer of the circuit substrate into a circuit layer can follow conventional circuit board fabrication processes. For example, copper is deposited on the circuit substrate, and then the conductive layer is formed into a circuit board through lamination, exposure and development, and etching. For example, the circuit substrate may or may not include an inner circuit board. When an inner circuit board is included, the number of inner circuit boards can be one or more. When the circuit substrate includes an inner circuit board, the inner circuit board can be fabricated first using conventional processes, and then a copper-clad substrate can be laminated to the top or bottom to form a circuit substrate containing an inner circuit board.

[0019] Step S102: Identify the image of the etched void 2010. For example, an image of the circuit board after the circuit layer has been formed can be acquired using a CCD camera. Then, the image is processed using methods including image denoising, image binarization, and region of interest extraction to identify the image of the etched void 2010 and obtain the center coordinates of the image. The above identification and center coordinate acquisition methods are conventional techniques. Forming an annular gap 30 facilitates rapid identification of the etched void 2010.

[0020] Step S103: Drill a hole in the marking part 20 according to the center coordinates of the image to form a positioning hole 201. The positioning hole 201 is located within the area defined by the annular gap 30, that is, the positioning hole 201 will not exceed the inner edge of the annular gap 30. Specifically, the lower computer controls the drill bit to move to the center position of the marking part 20 for drilling according to the center coordinate position obtained by the upper computer. For example, the size and type of the positioning hole 201 can be controlled according to the preset drill bit model and sinking amount. For example, the positioning hole 201 can be either a blind hole or a through hole. How the upper computer and the lower computer cooperate to realize the drill bit drilling to the predetermined position is a conventional technology, and the specific control logic will not be described in detail. During subsequent punching, the positioning hole 201 cooperates with the positioning part of the punching fixture to limit the circuit board in a fixed position.

[0021] In this application, after the conductive layer of the circuit board is fabricated into a circuit layer to form a circuit board, etched gaps 2010 are pre-formed in the marking portion of the circuit layer. Then, an image of the etched gaps 2010 is identified, and holes are drilled in the marking portion 20 according to the center coordinates of the image. Therefore, even if the circuit board expands or contracts, the drilling position in this application is at a preset position outside the corresponding circuit portion 10. That is, the solution in this application has a corrective function, ensuring that the relative position between the positioning hole 201 and the circuit portion 10 will not deviate due to the expansion or contraction of the circuit board. This improves the positioning accuracy of the circuit board and enhances its forming quality. Furthermore, the fabrication method in this application is simple, which also helps improve production efficiency and reduce manufacturing costs.

[0022] In some embodiments, refer to Figure 2 The annular gap 30 includes a gap ring 301 and at least two gap grooves 302. The gap grooves 302 communicate with the gap ring 301 and extend toward the center of the marking portion 20. The at least two gap grooves 302 are spaced apart around the center of the marking portion 20. For example, the gap grooves 302 can be formed together with the forming steps of the circuit portion 10 and the gap ring 301, or they can be formed after the forming of the circuit portion 10 and the gap ring 301 by means of coating, exposure development, and etching. In the drilling step, the positioning hole 201 is isolated from both the gap ring 301 and the gap grooves 302. The positioning hole 201 obtained in this way also helps to enhance the mechanical strength of the positioning hole 201 and further improve the positioning accuracy.

[0023] In some embodiments, the number of gap grooves 302 is four, and each pair of gap grooves 302 is symmetrically arranged relative to the center position of the marking part 20, which helps to further improve the positioning accuracy with fewer positioning points, and also helps to improve the mechanical strength of the positioning hole 201.

[0024] In some embodiments, the circumferentially adjacent gaps 302 are equally spaced, which helps to further improve the positioning accuracy and the mechanical strength of the positioning hole 201.

[0025] In some embodiments, the gap ring 301 has a circular shape. The gap structure helps to improve the utilization rate of the circuit board surface.

[0026] In another embodiment, the gap ring 301 can be a square structure or an irregular shape.

[0027] In some embodiments, the cross-section of the gap groove 302 is square, which helps to improve the ease of forming the gap groove 302.

[0028] In another embodiment, the cross-section of the gap groove 302 can be an irregular shape or a semi-circular shape.

[0029] In some embodiments, the manufacturing method further includes the step of: evaluating the pass / fail status of the circuit board opening based on the spacing between the positioning hole 201 and each gap groove 302; if the positioning hole 201 and each gap groove 302 are separated, the opening is pass / fail; if the positioning hole 201 and one of the gap grooves 302 are connected, the opening is fail / fail. Exemplarily, an AOI visual inspection instrument can be used to determine the pass / fail status of the opening, thereby improving the judgment speed. It is understood that manual judgment is also possible. Adding a step to determine the pass / fail status of the opening further ensures the quality of the circuit board.

[0030] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing positioning holes on a circuit board, characterized in that, Includes the following steps: The conductive layer of the circuit substrate is fabricated into a circuit layer, the circuit layer including a circuit portion and a marking portion. When viewed relative to the circuit layer, there is an annular gap between adjacent marking portions and circuit portions, and the marking portion has an etched gap. The etched gap and the annular gap are coaxially arranged. Image identifying the etched gaps; The marking portion is drilled according to the center coordinates of the image to form a positioning hole, which is located within the area defined by the annular gap.

2. The preparation method according to claim 1, characterized in that, The annular gap includes a gap ring and at least two gap grooves. The gap grooves are connected to the gap ring and extend toward the center of the marking portion. At least two of the gap grooves are spaced apart around the center of the marking portion. During the drilling process, the positioning hole is isolated from the gap ring and the gap groove.

3. The preparation method according to claim 2, characterized in that, The number of the gap grooves is four, and each pair of gap grooves is symmetrically arranged relative to the center position of the marking part.

4. The preparation method according to claim 2, characterized in that, It also includes the following steps: The quality of the circuit board opening is evaluated based on the distance between the positioning hole and each of the gap slots. If the positioning hole and each of the gap slots are separated, the opening is qualified. If the positioning hole and one of the gap slots are connected, the opening is unqualified.

5. The preparation method according to claim 2, characterized in that, The gap ring has a circular shape.

6. The preparation method according to claim 5, characterized in that, The cross-section of the gap groove is square.

7. The preparation method according to claim 3, characterized in that, The gaps are spaced at equal intervals between any two adjacent gaps in the circumferential direction.

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