Detection method and detection equipment for gold suspension ratio of PCB (Printed Circuit Board) golden finger
By using a ranging lens on the PCB to project and rotate the light source, the gold ratio is calculated and combined with automatic early warning, which solves the problem of low detection efficiency in the existing technology and realizes non-destructive and efficient gold ratio detection.
Patent Information
- Application Number
- CN202511870278.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-12-12
- Publication Date
- 2026-03-03
AI Technical Summary
Existing methods for detecting gold plating on PCB gold fingers are time-consuming and destructive, and cannot achieve full inspection, resulting in low inspection efficiency.
The detection equipment with a range measuring lens is used to measure the thickness and rotation angle of the gold finger area by projecting and rotating the light source, calculate the gold suspension ratio, and provide automatic early warning based on pre-stored experience data.
It achieves non-destructive testing of the gold finger suspension ratio on PCBs, improving testing efficiency and coverage, avoiding destructive cutting of PCBs, and ensuring that every PCB can be tested.
Smart Images
Figure CN121595585A_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of printed circuit board production and testing technology, and in particular to a method and equipment for testing the gold-to-gold ratio of PCB gold fingers. Background Technology
[0002] PCBs and main devices are typically connected via through-hole boards, which involve gold fingers designed on the PCB, commonly seen in computer graphics cards and memory modules. The typical manufacturing process for PCB gold fingers is as follows: conductive lines are designed to connect to the board edge; current is applied through the board edge; gold is electroplated onto the gold finger area; and then the conductive lines are etched away. Because the etching process involves the chemicals etching in the same direction along the lines, the conductive lines are cleaned vertically, but this process also allows the gold layer to penetrate below the gold fingers, resulting in a suspended gold layer, commonly known as "suspended gold." This suspended gold layer can cause the through-hole board to bend and detach during subsequent use, affecting connection stability. Suspended gold is relatively common, and as long as it is within acceptable limits, it does not significantly affect the use of the PCB. However, evaluating the extent of suspended gold on the manufactured gold fingers is a crucial quality control measure.
[0003] In existing technologies, the gold plating condition of PCBs is often detected by slicing. Although this method is accurate, it is very time-consuming and destructive, requiring the PCB to be cut open. Once cut, the PCB must be scrapped, so it can only be sampled for inspection. Summary of the Invention
[0004] Therefore, it is necessary to provide a method and equipment for detecting the gold suspension ratio of PCB gold fingers to address at least one of the problems mentioned above.
[0005] In a first aspect, the present invention provides a method for detecting the gold suspension ratio of PCB gold fingers, comprising the following steps: Place the PCB to be inspected on a worktable equipped with a rangefinder lens; The ranging lens illuminates the PCB from the normal direction to measure the thickness h of the gold finger area of the PCB; Move the ranging lens between the gold-plated clip area and the gold finger area of the PCB, and gradually rotate the ranging lens until the edge of the gold finger area is observed to be collinear with the bottom edge of the suspended area below the gold finger area, and record the rotation angle θ. The gold suspension ratio of the PCB gold fingers is determined based on the thickness h and the rotation angle.
[0006] In some implementations of the first aspect, the step of measuring the thickness h of the gold finger region of the PCB includes: The ranging lens illuminates the gold finger area of the PCB to obtain the height h1; Move the ranging lens outside the gold finger area to measure the distance h2 of the worktable surface; The thickness h of the gold finger region is obtained based on the height h1 and the spacing h2.
[0007] In combination with the first aspect and the above implementations, in some implementations of the first aspect, the ranging lens includes a laser rangefinder and a visual camera.
[0008] Combining the first aspect and the above implementation methods, in some implementation methods of the first aspect, after the step of determining the gold-plating ratio of the PCB gold fingers, the method further includes: comparing the gold-plating ratio with a pre-stored range of empirical data on gold-plating ratios; if the gold-plating ratio is outside the range of empirical data on gold-plating ratios, an early warning message is automatically issued.
[0009] Secondly, the present invention also provides a detection device for the gold-finger suspension ratio of PCB, for performing the detection method for the gold-finger suspension ratio of PCB as described in any one of the first aspects of the present invention, comprising a worktable and a ranging lens with a movable cantilever.
[0010] The technical solutions provided in the embodiments of the present invention bring the following beneficial technical effects: The PCB gold finger suspension ratio detection method provided by this invention uses light sources projected at different angles. Based on the signals appearing at different positions of the light source on the gold fingers of the printed circuit board, the copper thickness is calculated through the signals, and the suspension ratio of the PCB gold fingers is estimated. There is no need to destroy and disassemble the PCB. The measurement is accurate and convenient, and it can detect every PCB, with a high quality inspection coverage.
[0011] Additional aspects and advantages of this application will be set forth in the following sections and will be understood in detail from the following description, or may be learned by specific practice of the invention. Attached Figure Description
[0012] Figure 1 This is a flowchart illustrating a method for detecting the gold suspension ratio of PCB gold fingers in one embodiment of the present invention. Figure 2 This is a schematic diagram of the operation of S200 in one embodiment of the present invention; Figure 3 This is a schematic diagram of the operation of S300 in one embodiment of the present invention; Figure 4 This is a schematic diagram of the operation of S400 in one embodiment of the present invention.
[0013] Explanation of reference numerals in the attached figures: 10-Worktable, 20-Range measuring lens, 30-PCB, 31-Gold-plated fingers. Detailed Implementation
[0014] To facilitate understanding of the present invention, a more complete description will be given below with reference to the accompanying drawings. Possible embodiments of the invention are shown in the drawings. However, the invention can be implemented in many different forms and is not limited to the embodiments described herein with reference to the drawings. The embodiments described with reference to the drawings are exemplary and intended to provide a more thorough and complete understanding of the disclosure of the invention, and should not be construed as limiting the invention. Furthermore, detailed descriptions of known techniques may be omitted where such details are not essential to the features of the illustrated invention.
[0015] Those skilled in the art will understand that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the same meaning as in the prior art and should not be interpreted in an idealized or overly formal sense unless specifically defined as herein.
[0016] Those skilled in the art will understand that, unless specifically stated otherwise, the singular forms “a,” “an,” “the,” and “the” used herein may also include the plural forms. It should be further understood that the term “comprising” as used in the specification of this application means the presence of the stated features, integers, steps, operations, elements, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof. It should be understood that the term “and / or” as used herein includes all or any units and all combinations of one or more associated listed items.
[0017] The technical solution of the present invention and how the technical solution solves the above-mentioned technical problems will be described in detail below with specific embodiments.
[0018] An embodiment of the first aspect of the present invention provides a method for detecting the gold suspension ratio of PCB gold fingers, such as... Figure 1 As shown, it includes the following steps: S100: Place the PCB to be inspected on a worktable equipped with a rangefinder lens. In one specific implementation, the rangefinder lens includes a laser rangefinder and a vision camera.
[0019] S200: The rangefinder lens illuminates the PCB from the normal direction to measure the thickness h of the gold finger area of the PCB.
[0020] S300: Move the rangefinder lens between the gold-plated clip area and the gold finger area on the PCB, and gradually rotate the rangefinder lens until the edge of the gold finger area is observed to be collinear with the bottom edge of the suspended area below the gold finger area. Record the rotation angle θ.
[0021] S400: Determine the gold suspension ratio of the PCB gold fingers based on the thickness h and rotation angle.
[0022] The PCB gold finger suspension ratio detection method provided by this invention uses light sources projected at different angles. Based on the signals appearing at different positions of the light source on the gold fingers of the printed circuit board, the copper thickness is calculated through the signals, and the suspension ratio of the PCB gold fingers is estimated. There is no need to destroy and disassemble the PCB. The measurement is accurate and convenient, and it can detect every PCB, with a high quality inspection coverage.
[0023] Specifically, in some implementations of the first aspect of the present invention, such as Figure 2 As shown, the steps for measuring the thickness h of the gold finger area of the PCB include: Illuminate the gold finger area of the PCB with a rangefinder lens to obtain the height h1; Move the rangefinder lens outside the gold finger area and measure the distance h2 between the worktable surface; The thickness h of the gold finger region is obtained based on the height h1 and the spacing h2.
[0024] In a further embodiment of the first aspect of the present invention, following the step of determining the gold-plating ratio of the PCB gold fingers in S400, the method further includes: comparing the gold-plating ratio with a pre-stored range of empirical gold-plating ratio data; if the gold-plating ratio is outside the range of empirical gold-plating ratio data, automatically issuing a warning. By comparing the measured data with historical empirical data on the gold-plating ratio of the PCB gold fingers, if there is a significant deviation, a warning is issued in a timely manner, automatically realizing detection reminders and improving work efficiency.
[0025] refer to Figures 2-4 The following are the specific operating procedures: Step 1: Place the PCB to be tested at the preset position on the workbench, and illuminate it at two positions using the rangefinder lens, such as... Figure 2 As shown, the thickness data h of the gold finger area of the PCB is obtained.
[0026] Step 2: View vertically through the magnifying glass in the rangefinder lens, such as... Figure 3 As shown, only point a of the PCB is visible; point c is not.
[0027] Step 3: Tilt and rotate the rangefinder lens until point c is visible, as shown below. Figure 4 As shown, record the angle θ of the tilt rotation.
[0028] Based on the above measurement results, the length of the suspended part of the gold finger is estimated to be m=h(1+tan(x)), and the bottom corner etching amount is n=h·tan(x). The ratio of the two is recorded as the gold suspension ratio n / m. The gold suspension ratio data guides the adjustment of the gold finger production process.
[0029] Based on the same inventive concept, an embodiment of the second aspect of the present invention provides a PCB gold finger suspension ratio detection device for performing the PCB gold finger suspension ratio detection method of any of the first aspects of the present invention, which includes at least a worktable and a ranging lens with a movable cantilever, and may also include corresponding fixtures or automated mobile loading devices, etc.
[0030] Those skilled in the art will understand that the steps, measures, and solutions in the various operations, methods, and processes discussed in this application can be alternated, modified, combined, or deleted. Furthermore, other steps, measures, and solutions in the various operations, methods, and processes discussed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted. Furthermore, steps, measures, and solutions in the prior art that are similar to those disclosed in this application can also be alternated, modified, rearranged, decomposed, combined, or deleted.
[0031] The terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this application, unless otherwise stated, "a plurality of" means two or more.
[0032] In the description of this application, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal communication between two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0033] In the description of this specification, specific features, structures, materials, or characteristics may be combined in any suitable manner in one or more embodiments or examples.
[0034] It should be understood that although the steps in the flowcharts of the accompanying figures are shown sequentially as indicated by the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the accompanying figures may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily completed at the same time, but can be executed at different times, and their execution order is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the sub-steps or stages of other steps.
[0035] The above description is only a partial embodiment of this application. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of this application, and these improvements and modifications should also be considered within the scope of protection of this application.
Claims
1. A method for detecting the gold suspension ratio of PCB gold fingers, characterized in that, Includes the following steps: Place the PCB to be inspected on a worktable equipped with a rangefinder lens; The ranging lens illuminates the PCB from the normal direction to measure the thickness h of the gold finger area of the PCB; Move the ranging lens between the gold-plated clip area and the gold finger area of the PCB, and gradually rotate the ranging lens until the edge of the gold finger area is observed to be collinear with the bottom edge of the suspended area below the gold finger area, and record the rotation angle θ. The gold suspension ratio of the PCB gold fingers is determined based on the thickness h and the rotation angle.
2. The method for detecting the gold suspension ratio of PCB gold fingers according to claim 1, characterized in that, The step of measuring the thickness h of the gold finger area of the PCB includes: The ranging lens illuminates the gold finger area of the PCB to obtain the height h1; Move the ranging lens outside the gold finger area to measure the distance h2 of the worktable surface; The thickness h of the gold finger region is obtained based on the height h1 and the spacing h2.
3. The method for detecting the gold suspension ratio of PCB gold fingers according to claim 1, characterized in that, The ranging lens includes a laser rangefinder and a vision camera.
4. The method for detecting the gold suspension ratio of PCB gold fingers according to claim 1, characterized in that, After determining the gold-plating ratio of the PCB gold fingers, the method further includes: comparing the gold-plating ratio with a pre-stored range of empirical gold-plating ratio data; if the gold-plating ratio is outside the range of empirical gold-plating ratio data, an early warning message is automatically issued.
5. A testing device for the gold suspension ratio of PCB gold fingers, characterized in that, The method for detecting the gold-fingered ratio of PCB gold fingers according to any one of claims 1 to 4 includes a worktable and a ranging lens with a movable cantilever.