Method for improving copper sheet rolling aiming at PCB (printed circuit board) production hole design
During the CNC trimming process of the PCB board, the milling cutter is controlled to press the target copper skin area and then carry the knife to remove the target copper skin area, which solves the problem of copper skin rolling up, improves product quality and reduces the chance of scrapping.
Patent Information
- Application Number
- CN202411410490.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-10
- Publication Date
- 2025-03-21
AI Technical Summary
During the CNC trimming process of PCB board, the copper skin is easily rolled up by a rotating milling cutter, which affects the yield rate.
By controlling the starting point of the milling cutter, the starting point of the milling cutter falls into the center of the target copper skin area, and the target copper skin area is pressed at the cutting part of the milling cutter, and the milling cutter carries the cutter toward the edge of the PCB board to remove the target copper skin area.
It effectively prevents copper skin from rolling up, improves product quality, and reduces the chance of scrapping.
Smart Images
Figure CN119676957A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the field of PCB production, and in particular to a method for improving copper sheet rolling in hole design of PCB production. Background Art
[0002] PCB, full name Printed Circuit Board, is an electronic component used to achieve electronic connections in electronic devices. PCB consists of an insulating substrate, a conductive layer (copper foil) and possible connecting elements. These conductive layers are arranged according to the designed circuit diagram to achieve the transmission of electronic signals; In the process of PCB board production, the production process includes PTH, primary copper, negative dry film, secondary copper, secondary drilling, CNC trimming, etching and tin stripping, outer layer AOI, solder mask, and finished product packaging. In the CNC trimming process, the copper-clad part of the edge hole of the semi-finished product needs to be trimmed by a milling cutter. The direction of the milling cutter is often moved according to the edge of the semi-finished product. However, it is found in practice that this method will cause the copper sheet to be rolled up by the rotating milling cutter during the trimming process, affecting the yield rate. Therefore, there should be a more reasonable method to solve the above problems. Summary of the invention
[0003] The present invention provides a solution to the technical problem that in the production process of PCB boards in the prior art, the copper sheet is rolled up by the rotating milling cutter during the trimming process, thereby affecting the yield rate.
[0004] To achieve the above object, the present invention provides a method for improving copper foil rolling up in hole design of PCB production, comprising the following steps: S1, obtaining the target copper area in the semi-finished PCB board; S2, controlling the starting point of the milling cutter to fall into the center of the target copper skin area, controlling the cutting portion of the milling cutter to press the target copper skin area, and controlling the milling cutter to move toward the edge of the PCB board to remove the target copper skin area.
[0005] As an improved solution of the present application, before step S1, the semi-finished PCB board needs to be drilled and the formed holes need to be copper-plated; in step S1, the target copper area is determined based on the hole position.
[0006] As an improved solution of the present application, before the copper plating, it is also necessary to coat the edge of the semi-finished PCB board with a solder resist dry film, and the area of the solder resist dry film forms a copper-free area.
[0007] As an improved solution of the present application, the width of the copper-free area is 6-8 mil.
[0008] As an improved solution of the present application, before step S2, a pattern line is formed on the surface of the semi-finished PBC board, and the pattern line is provided with an avoidance area for avoiding the hole, and the target copper skin area is located in the avoidance area.
[0009] As an improvement scheme of the present application, in step S2, the cutting line formed by the milling cutter includes a first part and a second part, the first part is the starting point position reaching the copper-free area; the second part takes the end point of the first part as the starting point, and extends the template line toward the two ends of the semi-finished PCB board to remove the copper-free area.
[0010] As an improved solution of the present application, in step S2, the two milling cutters are controlled to simultaneously reach the end point of the first part, and then move in two opposite directions along the template to generate the second part.
[0011] As an improved solution of the present application, the cutting depth of the first part is greater than the thickness of the target copper skin area.
[0012] As an improved solution of the present application, the cutting depth of the second part is the thickness of the semi-finished PCB board.
[0013] The beneficial effects of the present invention are as follows: compared with the prior art, the present invention provides a method for improving copper sheet rolling for hole design of PCB board production, comprising the following steps: S1, obtaining a target copper sheet area in a semi-finished PCB board; S2, controlling the starting point of a milling cutter to fall into the center of the target copper sheet area, controlling the cutting part of the milling cutter to press the target copper sheet area, and controlling the milling cutter to cut toward the edge of the PCB board to remove the target copper sheet area; by changing the milling cutter to press the target copper sheet area first and then cut and trim the target copper sheet area, the target copper sheet area will not be pulled by force based on the rotation of the milling cutter to form a rolling portion, which can effectively improve product quality and reduce the probability of scrapping. BRIEF DESCRIPTION OF THE DRAWINGS
[0015] Figure 1 It is a schematic diagram of the processing effect of the prior art; Figure 2 Another schematic diagram of the processing effect of the prior art; Figure 3 It is a schematic diagram of the processing effect of the present invention; Figure 4 It is another schematic diagram of the processing effect of the present invention.
[0016] The main component symbols are described as follows: A. Cutting direction; B. Unintended copper plating part; C. Hole part; 1. Target copper area; 2. First part; 3. Second part; 4. Copper-free area; 5. Hole part. DETAILED DESCRIPTION
[0018] In order to more clearly illustrate the present invention, the present invention is further described below in conjunction with the accompanying drawings.
[0019] In the following description, the example details are given to provide a deeper understanding of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all embodiments. It should be understood that the specific embodiments are only used to explain the present invention and are not used to limit the present invention.
[0020] It should be understood that when the terms "include" and / or "comprises" are used in this specification, they indicate the existence of the stated features, integers, steps, operations, elements or components, but do not exclude the existence or addition of one or more other features, integers, steps, operations, elements, components or combinations thereof.
[0021] In the process of PCB board production, the production process includes PTH, primary copper, negative film, secondary copper, secondary drilling, CNC trimming, etching and tin stripping, outer layer AOI, solder mask, and finished product packaging. In the CNC trimming process, the copper-clad part of the edge hole of the semi-finished product needs to be trimmed by a milling cutter. Please refer to Figure 1 The cutting direction A of the milling cutter is often moved according to the edge of the semi-finished product, and the blade of the milling cutter is used to cut and trim the unexpected copper-plated part B on the edge of the PCB board. After completion, the hole C is exposed. However, it is found in actual operation that this method will cause the copper sheet to roll up due to the force of the rotating milling cutter during the trimming process, affecting the yield rate; therefore, there should be a more reasonable method to solve the above problems.
[0022] In order to solve the above-mentioned technical problems, the present application provides a method for improving the copper foil rolling up in the design of the hole portion 5 of the PCB board production. Figure 3 To Attachment Figure 4 , including the following steps: S1, obtaining the target copper area 1 in the semi-finished PCB board; S2, controlling the starting point of the milling cutter to fall into the center of the target copper skin area 1, controlling the cutting portion of the milling cutter to press the target copper skin area 1, and controlling the milling cutter to move toward the edge of the PCB board to remove the target copper skin area 1.
[0023] By changing the milling cutter to first press the target copper skin area 1 and then cut and trim it, the target copper skin area 1 will not be pulled by the rotation of the milling cutter to form a rolled-up portion, which can effectively improve product quality and reduce the probability of scrap.
[0024] In the present embodiment, before step S1, it is necessary to perform hole drilling on the semi-finished PCB board and perform copper plating on the formed hole portion 5; in step S1, the target copper skin area 1 is determined based on the position of the hole portion 5; hole drilling and copper plating are common in the production of PCB boards, and the copper plating of the hole portion formed by drilling can ensure the connectivity of the printed circuit, ensuring that the components carried later can function normally; in the present embodiment, the target copper skin area 1 is determined according to the position of the hole portion 5, and the area is removed and trimmed with a milling cutter to ensure the stability of the circuit conduction.
[0025] In a further solution, before copper plating, it is necessary to coat the edge of the semi-finished PCB board with a solder mask dry film, and the area of the solder mask dry film is used to form a copper-free area 4. It is not difficult to understand that by coating the solder mask dry film, the covered part is not covered by the copper sheet during copper plating and attached to the edge of the semi-finished PCB. The semi-finished PCB board can be better cut by the milling cutter due to the lack of copper sheet interference, and there will be no curling or poor flatness caused by material differences during cutting; in the specific solution, the width of the copper-free area 4 is 6-8 mil.
[0026] In this embodiment, before step S2, a pattern line is formed on the surface of the semi-finished PBC board, and the pattern line is provided with an avoidance area for avoiding the hole portion 5, and the target copper skin area 1 is located in the avoidance area; it is not difficult to understand that due to the various forms of electronic equipment, the internal assembly structure is also different. Therefore, according to the actual application of the user, the expected pattern can be obtained by cutting along the pattern line with a milling cutter, and the corresponding hole portion 5 is correspondingly formed with an avoidance area, and the target copper skin area 1 is exposed through the avoidance area to facilitate cutting correction by the milling cutter.
[0027] In this embodiment, in step S2, the cutting line formed by the movement of the milling cutter includes a first part 2 and a second part 3, the first part 2 is the starting point to reach the copper-free area 4; the second part 3 takes the end point of the first part 2 as the starting point, and extends the value pattern line toward the two ends of the semi-finished PCB board to remove the copper-free area 4; it is not difficult to understand that during the first part 2, the milling cutter has been pressing the target copper skin area 1, which can effectively prevent the copper skin in this area from rolling up. After the first part 2 is completed, the second part 3 is implemented, and the second part 3 cuts the copper-free area 4, because this part has no copper skin connected to the target copper skin area 1, and there will be no copper skin in the adjacent area pulled in the second part 3 to cause damage to the circuit.
[0028] In a more optimal solution, in order to achieve more efficient cutting, in this embodiment, in step S2, the two milling cutters are controlled to move at the same time to reach the end point of the first part 2, and then move in two opposite directions along the template to generate the second part 3; by processing the target copper area 1 when the two milling cutters pass through, the obtained template semi-finished PCB board can be quickly obtained, and then the subsequent processing steps can be quickly entered to complete the overall processing.
[0029] In a more optimal solution, the cutting depth of the first part 2 is greater than the thickness of the target copper skin area 1; it is not difficult to understand that by determining the cutting depth of the first part 2, the copper skin covering the hole 5 can be effectively removed; further, the cutting depth of the second part 3 is the thickness of the semi-finished PCB board, and the semi-finished PCB board can be trimmed as a whole.
[0030] The advantages of the present invention are: 1. By changing the milling cutter to press the target copper area first and then cut and trim, the target copper area will not be pulled by the rotation of the milling cutter to form a rolled-up part, which can effectively improve product quality and reduce the chance of scrap.
[0031] 2. By applying the solder mask dry film, the covered part will not be covered by the copper foil during copper plating and attached to the edge of the semi-finished PCB. The semi-finished PCB board can be better cut by the milling cutter without the interference of the copper foil, and there will be no curling or poor flatness caused by uneven materials during cutting.
[0032] The above disclosures are only several specific embodiments of the present invention, but the present invention is not limited thereto, and any changes that can be conceived by those skilled in the art should fall within the protection scope of the present invention.
Claims
1. A method for improving copper foil rolling up in hole design of PCB production, characterized in that: The following steps are involved: S1, obtaining the target copper area in the semi-finished PCB board; S2, controlling the starting point of the milling cutter to fall into the center of the target copper skin area, controlling the cutting portion of the milling cutter to press the target copper skin area, and controlling the milling cutter to move toward the edge of the PCB board to remove the target copper skin area.
2. The method for improving copper foil rolling up in hole design of PCB production according to claim 1, characterized in that: Before step S1, the semi-finished PCB board needs to be drilled and the formed holes need to be copper plated. In step S1, the target copper area is determined based on the hole position.
3. The method for improving copper foil rolling up in hole design of PCB production according to claim 2, characterized in that: Before the copper plating, it is also necessary to coat the edge of the semi-finished PCB board with a solder resist dry film, and the area of the solder resist dry film forms a copper-free area.
4. The method for improving copper foil rolling up in hole design of PCB production according to claim 3, characterized in that: The width of the copper-free area is 6-8 mil.
5. The method for improving copper foil rolling up in hole design of PCB production according to claim 3, characterized in that: Before step S2, a pattern line is formed on the surface of the semi-finished PBC board, and the pattern line is provided with a avoidance area for avoiding the hole, and the target copper skin area is located in the avoidance area.
6. The method for improving copper foil rolling up in hole design of PCB production according to claim 5, characterized in that: In step S2, the cutting line formed by the milling cutter includes a first part and a second part, wherein the first part is the starting point to reach the copper-free area; the second part takes the end point of the first part as the starting point, and extends along the template line toward the two ends of the semi-finished PCB board to remove the copper-free area.
7. The method for improving copper foil rolling up in hole design of PCB production according to claim 6, characterized in that: In step S2, the two milling cutters are controlled to reach the end point of the first part at the same time, and then move in two opposite directions along the template to generate the second part.
8. The method for improving copper foil rolling up in hole design of PCB production according to claim 7, characterized in that: The cutting depth of the first portion is greater than the thickness of the target copper skin area.
9. The method for improving copper foil rolling up in hole design of PCB production according to claim 7, characterized in that: The cutting depth of the second portion is equal to the thickness of the semi-finished PCB board.