A method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges

Abstract

This invention discloses a method for improving the dimensional accuracy of double-sided gold finger patterns to the outer edge, specifically relating to the field of printed circuit board manufacturing. The method includes the following steps: Step S1, creating a unique QR code on the PCB board for single-board identification; Step S2, a CCD milling machine captures the expansion and contraction data of the gold finger patterns on both the TOP and BOTTOM sides, and stores them in conjunction with the QR code; Step S3, before milling the outer edge, the CCD milling machine retrieves the double-sided expansion and contraction data corresponding to the QR code for comprehensive compensation; Step S4, based on the compensated data, the PCB outline is milled to achieve high-precision alignment between the double-sided gold finger patterns and the outer edge. In Step S1, the unique QR code is created on a non-functional area of ​​the PCB board using laser engraving or ink printing. This invention achieves precise compensation of double-sided gold finger expansion and contraction data through a single-board QR code, significantly improving dimensional accuracy and assembly yield, reducing rework and scrap, and is suitable for high-density PCB mass production.

Description

Technical Field

[0001] This invention relates to the field of printed circuit board manufacturing, and more specifically, to a method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges. Background Technology

[0002] PCB manufacturing requires multi-layer lamination, and the substrate is prone to dimensional expansion and contraction deformation, resulting in dimensional deviations between the gold finger patterns on the TOP / BOTTOM sides and the outer edge. Furthermore, the expansion and contraction on both sides are often inconsistent, further exacerbating the asymmetrical offset of the gold fingers relative to the outer edge.

[0003] Traditional PCB manufacturing relies solely on the top surface pattern, failing to provide synchronous alignment compensation for the bottom surface. This easily leads to excessive dimensional deviations between the two surfaces. In areas with fine-pitch gold fingers and high-density connectors, even minute positional deviations can cause functional issues such as short circuits, open circuits, gold finger misalignment, connector assembly failures, and poor contact. This severely reduces product reliability and yield, while increasing rework, scrap, and repair costs, hindering the mass production of high-precision PCB products such as high-frequency, high-speed, optical modules, and low-orbit satellites.

[0004] To address the aforementioned problems, a technical solution is provided. Summary of the Invention

[0005] In order to overcome the above-mentioned defects of the prior art, the embodiments of the present invention provide a method for improving the manufacturing accuracy of double-sided gold finger patterns to the outer edge dimensions to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: A method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges includes the following steps: Step S1: Create a unique QR code on the PCB board for single-board identification. Step S2: The CCD milling machine captures the expansion and contraction data of the gold finger graphics on the TOP and BOTTOM sides respectively, and stores them in conjunction with the QR code. Step S3: Before milling the outer shape, the CCD milling machine retrieves the double-sided expansion and contraction data of the corresponding QR code for comprehensive compensation. Step S4: Based on the compensated data, complete the PCB outline milling process to achieve high-precision alignment between the double-sided gold finger pattern and the outline edge.

[0007] In a preferred embodiment, in step S1, the unique identification QR code is made on the non-functional area of ​​the PCB board by laser engraving or ink printing. The QR code information corresponds one-to-one with a single PCB, realizing the independent identification of a single PCB.

[0008] By using the above methods, we can ensure that the expansion and contraction data of each PCB can be collected, stored, and retrieved independently, thus avoiding data confusion among multiple boards.

[0009] In a preferred embodiment, in step S2, the CCD milling machine automatically identifies the QR code on the PCB board using its built-in CCD lens and uses the board as a unique index for data storage and matching.

[0010] The above method enables rapid binding of QR codes with double-sided expansion and contraction data, achieving identity matching without manual intervention, improving data collection efficiency, and avoiding matching errors caused by manual recording.

[0011] In a preferred embodiment, in step S2, the CCD milling machine collects the target point position data of the gold finger pattern on the TOP surface and BOTTOM surface respectively, records the offset caused by lamination expansion and contraction on the two surfaces, and binds it to the corresponding QR code and saves it to the device system. The CCD milling machine grips the TOP and BOTTOM surfaces and sets 2 to 4 gold finger reference targets each.

[0012] Using the above method, multi-target acquisition can comprehensively cover the expansion and contraction distribution of the gold finger area, avoiding the random errors of single-point acquisition and ensuring the accuracy of expansion and contraction data.

[0013] In a preferred embodiment, in step S3, the CCD milling machine retrieves the expansion and contraction data of the TOP and BOTTOM sides of the PCB by scanning the QR code, and the system automatically calculates the comprehensive compensation value.

[0014] The above method enables rapid retrieval and automatic calculation of expansion and contraction data, eliminating the need for manual input of compensation parameters, shortening processing preparation time, avoiding compensation errors caused by manual calculation, and improving compensation accuracy.

[0015] In a preferred embodiment, step S3 includes comprehensive compensation, which includes uniformly correcting the positional deviation, dimensional expansion and contraction, and double-sided asymmetric offset of the gold finger pattern.

[0016] By employing the above methods, the problem of multiple dimensional deviations caused by the lamination process is specifically addressed, enabling comprehensive and precise correction of the double-sided gold finger pattern and eliminating the asymmetric deviations caused by single-sided datum processing.

[0017] In a preferred embodiment, in step S4, the CCD milling machine automatically generates the contour milling path based on the compensated data. The contour milling uses a carbide end mill and the milling feed speed is 5-15 m / min.

[0018] By using the above methods, carbide end mills, when paired with appropriate feed rates, ensure the stability and machining accuracy of profile milling, and avoid dimensional deviations caused by tool wear or excessive feed rate during milling.

[0019] In a preferred embodiment, in step S4, after the outline milling is completed, the dimensional deviations of the gold fingers on the TOP surface and BOTTOM surface relative to the outline edge are consistent.

[0020] By using the above methods, we can ensure the dimensional consistency between the double-sided gold fingers and the outer edge, meet the assembly requirements of high-precision PCB products such as fine-pitch connectors and high-frequency, high-speed connectors, and avoid assembly failures and poor contact caused by dimensional deviations.

[0021] The technical effects and advantages of the present invention regarding a method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges are as follows: 1. This invention binds double-sided expansion and contraction data through a unique QR code, enabling precise and personalized compensation for a single PCB, completely solving the problem of double-sided dimensional deviation caused by traditional single-sided reference processing, and controlling the dimensional accuracy from the gold fingers to the outer edge within ±0.05mm; 2. This invention employs multi-target data acquisition and automatic system comprehensive compensation, eliminating the need for manual intervention, thereby improving processing efficiency, avoiding human error, and significantly reducing product rework and scrap rates. It is suitable for the mass production needs of high-precision PCBs such as optical modules and low-orbit satellites. 3. This invention is compatible with existing CCD milling machines. The function can be realized simply by upgrading the software. There is no need to invest in a large number of new equipment. The transformation cost is low and the practicality is strong. At the same time, the data is traceable, which facilitates quality control and problem investigation in the production process. Attached Figure Description

[0022] Figure 1 This is a flowchart illustrating a method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to the present invention. Detailed Implementation

[0023] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0024] Example 1 Figure 1 This invention provides a method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges, specifically including the following steps: Step S1: Create a unique QR code on the PCB board for single-board identification. Step S2: The CCD milling machine captures the expansion and contraction data of the gold finger graphics on the TOP and BOTTOM sides respectively, and stores them in conjunction with the QR code. Step S3: Before milling the outer shape, the CCD milling machine retrieves the double-sided expansion and contraction data of the corresponding QR code for comprehensive compensation. Step S4: Based on the compensated data, complete the PCB outline milling process to achieve high-precision alignment between the double-sided gold finger pattern and the outline edge.

[0025] Specifically, in step S1, a unique QR code is created on a non-functional area of ​​the PCB board using laser engraving or ink printing. The QR code information corresponds one-to-one with each individual PCB, achieving independent identification for each board. In step S2, the CCD milling machine automatically recognizes the QR code on the PCB board using its built-in CCD lens and uses the board as the unique index for data storage and matching. In step S2, the CCD milling machine collects the target point position data of the gold finger patterns on the TOP and BOTTOM surfaces, records the offset caused by lamination expansion and contraction on both surfaces, and binds it to the corresponding QR code, saving it to the device system. The CCD milling machine grasps the TOP and BOTTOM surfaces... Two gold finger reference target points are set on each of the OM surfaces; in step S3, the CCD milling machine retrieves the expansion and contraction data of the TOP and BOTTOM surfaces of the PCB by scanning the QR code, and the system automatically calculates the comprehensive compensation value; in step S3, the comprehensive compensation includes uniform correction of the gold finger graphic position deviation, dimensional expansion and contraction, and double-sided asymmetric offset; in step S4, the CCD milling machine automatically generates the outline milling path based on the compensated data, and the outline milling uses a carbide end mill with a milling feed speed of 5m / min; in step S4, after the outline milling is completed, the dimensional deviation of the gold fingers on the TOP and BOTTOM surfaces relative to the outline edge is consistent.

[0026] Example 2 Figure 1 This invention provides a method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges, specifically including the following steps: Step S1: Create a unique QR code on the PCB board for single-board identification. Step S2: The CCD milling machine captures the expansion and contraction data of the gold finger graphics on the TOP and BOTTOM sides respectively, and stores them in conjunction with the QR code. Step S3: Before milling the outer shape, the CCD milling machine retrieves the double-sided expansion and contraction data of the corresponding QR code for comprehensive compensation. Step S4: Based on the compensated data, complete the PCB outline milling process to achieve high-precision alignment between the double-sided gold finger pattern and the outline edge.

[0027] Specifically, in step S1, the unique identity QR code is made on the non-functional area of the PCB board by laser engraving or ink printing. The QR code information corresponds to each single PCB board one by one, realizing the unique identity identification of each single piece. In step S2, the CCD milling machine automatically identifies the QR code on the PCB board through its own CCD lens, and uses this board as the only index for data storage and matching. In step S2, the CCD milling machine respectively collects the target position data of the gold finger patterns on the TOP side and the BOTTOM side, records the offset generated by lamination expansion and contraction on both sides, and binds it to the corresponding QR code and saves it to the device system. The CCD milling machine grabs 3 gold finger reference targets on each of the TOP side and the BOTTOM side. In step S3, the CCD milling machine调取the expansion and contraction data of the corresponding TOP and BOTTOM sides of this PCB board by scanning the QR code, and the system automatically calculates the comprehensive compensation value. In step S3, the comprehensive compensation includes uniformly correcting the position deviation, size expansion and contraction, and double-sided asymmetric offset of the gold finger pattern. In step S4, the CCD milling machine automatically generates the profile milling path according to the compensated data. The profile milling uses a carbide milling cutter, and the milling feed speed is 10 m / min. In step S4, after the profile milling is completed, the size deviation of the gold finger relative to the profile edge on the TOP side and the BOTTOM side is the same.

[0028] Embodiment 3 Figure 1 A method for improving the dimensional accuracy of the double-sided gold finger pattern to the profile edge of the present invention is given, which specifically includes the following steps: Step S1, make a unique identity QR code on the PCB board for single-board identity identification; Step S2, the CCD milling machine respectively grabs the expansion and contraction data of the gold finger patterns on the TOP and BOTTOM sides, and binds and stores them with the QR code; Step S3, before milling the profile, the CCD milling machine调取the double-sided expansion and contraction data of the corresponding QR code for comprehensive compensation; Step S4, complete the PCB profile milling process based on the compensated data, and achieve high-precision alignment of the double-sided gold finger pattern and the profile edge.

[0029] It should be noted that the text "调取" in the original text seems to be a misspelling or an incomplete expression. It might need to be further clarified in the actual context to ensure more accurate translation. Here, a more general translation is used for the sake of presenting the overall meaning.Specifically, in step S1, a unique QR code is created on a non-functional area of ​​the PCB board using laser engraving or ink printing. The QR code information corresponds one-to-one with a single PCB, achieving independent identification for each PCB. In step S2, the CCD milling machine automatically recognizes the QR code on the PCB board using its built-in CCD lens and uses the board as the unique index for data storage and matching. In step S2, the CCD milling machine collects the target point position data of the gold finger patterns on the TOP and BOTTOM surfaces, records the offset caused by lamination expansion and contraction on both surfaces, and binds it to the corresponding QR code and saves it to the device system. The CCD milling machine grasps the TOP and BOTTOM surfaces. Four gold finger reference target points are set on each of the M surfaces; in step S3, the CCD milling machine retrieves the expansion and contraction data of the TOP and BOTTOM surfaces of the PCB by scanning the QR code, and the system automatically calculates the comprehensive compensation value; in step S3, the comprehensive compensation includes uniform correction of the gold finger graphic position deviation, dimensional expansion and contraction, and double-sided asymmetric offset; in step S4, the CCD milling machine automatically generates the outline milling path according to the compensated data, and the outline milling uses a carbide end mill with a milling feed speed of 15m / min; in step S4, after the outline milling is completed, the dimensional deviation of the gold fingers on the TOP and BOTTOM surfaces relative to the outline edge is consistent.

[0030] Using the manufacturing methods of Examples 1-3 and the conventional method as comparative examples, the dimensional accuracy of the gold fingers to the outer edge on the TOP surface and the dimensional accuracy of the gold fingers to the outer edge on the BOTTOM surface were statistically analyzed. The results are shown in the table below: The core difference between Examples 1-3 lies in the number of benchmark targets and the compensation range. The more targets and the more comprehensive the compensation coverage, the higher the accuracy and yield. Example 3 is the best example.

[0031] The above are merely specific embodiments of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

[0032] In conclusion, the above are merely preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges, characterized in that, Includes the following steps: Step S1: Create a unique QR code on the PCB board for single-board identification. Step S2: The CCD milling machine captures the expansion and contraction data of the gold finger graphics on the TOP and BOTTOM sides respectively, and stores them in conjunction with the QR code. Step S3: Before milling the outer shape, the CCD milling machine retrieves the double-sided expansion and contraction data of the corresponding QR code for comprehensive compensation. Step S4: Based on the compensated data, complete the PCB outline milling process to achieve high-precision alignment between the double-sided gold finger pattern and the outline edge.

2. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 1, characterized in that: In step S1, the unique identification QR code is made on the non-functional area of ​​the PCB board by laser engraving or ink printing. The QR code information corresponds one-to-one with a single PCB, realizing the independent identification of a single PCB.

3. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 2, characterized in that: In step S2, the CCD milling machine automatically identifies the QR code on the PCB board using its built-in CCD lens and uses the board as a unique index for data storage and matching.

4. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 3, characterized in that: In step S2, the CCD milling machine collects the target point position data of the gold finger pattern on the TOP surface and BOTTOM surface respectively, records the offset caused by lamination expansion and contraction on the two surfaces, and binds it to the corresponding QR code and saves it to the device system. The CCD milling machine grips the TOP and BOTTOM surfaces and sets 2 to 4 gold finger reference targets each.

5. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 4, characterized in that: In step S3, the CCD milling machine retrieves the expansion and contraction data of the TOP and BOTTOM sides of the PCB by scanning the QR code, and the system automatically calculates the comprehensive compensation value.

6. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 5, characterized in that: In step S3, the comprehensive compensation includes uniformly correcting the positional deviation, dimensional expansion and contraction, and double-sided asymmetric offset of the gold finger pattern.

7. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 6, characterized in that: In step S4, the CCD milling machine automatically generates the contour milling path based on the compensated data. The contour milling uses a carbide end mill with a milling feed rate of 5-15 m / min.

8. The method for improving the dimensional accuracy of double-sided gold finger patterns to their outer edges according to claim 7, characterized in that: In step S4, after the outer contour milling is completed, the dimensional deviations of the gold fingers on the TOP surface and BOTTOM surface relative to the outer contour edge are consistent.

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