A double-sided AOI detection mechanism for PCB circuit board

Abstract

The present application relates to AOI equipment technical field, especially in kind of double-sided AOI detection mechanism for PCB circuit board, single PCB board bearing space is provided with three clamping components, three clamping components are in triangular shape distribution, two of three clamping components are arranged in the inner side wall of outer ring, one of three clamping components is arranged in the outer side wall of inner ring, the clamping component is used for three-point fixation to PCB board, after the three-point fixation of PCB board by clamping component, the rest of PCB board is in the state of suspension.Compared with the prior art, the double-sided AOI detection mechanism for PCB circuit board can avoid the hard contact between components on the PCB and other components, effectively reduce the damage to the PCB during detection.

Description

[Technical Field]

[0001] This invention relates to the field of AOI equipment technology, and in particular to a double-sided AOI inspection mechanism for PCB circuit boards. [Background Technology]

[0002] AOI inspection equipment, also known as AOI optical automatic inspection equipment, is a device that detects common defects encountered in welding production based on optical principles. It is mainly used to detect whether there are defects in the surface printing of IC packaging, and whether there are dirt and spots on the display glass. During automatic inspection, the AOI inspection equipment automatically scans the display screen with a high-definition CCD camera, collects images, compares the test points with the qualified parameters in the database, detects defects in the display screen after image processing, and marks the defects on the display or through automatic marking.

[0003] In current PCB manufacturing processes, it is sometimes necessary to inspect both the top and bottom sides. Glass carriers are usually used to support the PCB for double-sided inspection. However, the side of the PCB that is in direct contact with the glass carrier is prone to damage during placement, which is not conducive to product inspection. [Summary of the Invention]

[0004] To overcome the above problems, this invention proposes a double-sided AOI inspection mechanism for PCB circuit boards that can effectively solve the above problems.

[0005] The present invention provides a technical solution to solve the above-mentioned technical problems: a double-sided AOI inspection mechanism for PCB circuit boards, including a support component and at least two inspection components, wherein the at least two inspection components are respectively disposed on the upper and lower sides of the support component, the support component is used to support and fix the PCB board, and the at least two inspection components are used to perform double-sided inspection on the PCB board;

[0006] The load-bearing component includes an inner ring and an outer ring, which are connected as a whole by a support frame. The outer ring is arranged around the inner ring, and a PCB board load-bearing space is formed between the inner ring and the outer ring. The PCB board load-bearing space is divided into four single PCB board load-bearing spaces by the support frame, and a PCB board can be fixed in each single PCB board load-bearing space.

[0007] The single PCB board bearing space is provided with three clamping components, which are distributed in a triangular shape. Two of the three clamping components are located on the inner sidewall of the outer ring, and one of the three clamping components is located on the outer sidewall of the inner ring. The clamping components are used to fix the PCB board at three points. After the PCB board is fixed at three points by the clamping components, the rest of the PCB board is in a suspended state.

[0008] Preferably, the four single PCB board bearing spaces are continuous in the horizontal direction, and the support frame only divides the four single PCB board bearing spaces in the vertical direction.

[0009] Preferably, the clamping assembly includes a fixed clamping plate and a movable clamping plate. The movable clamping plate is located above the fixed clamping plate, and a clamping micro-actuator is connected to the movable clamping plate. The clamping micro-actuator controls the lifting and lowering of the movable clamping plate to achieve clamping and releasing of the PCB board.

[0010] Preferably, the outer ring side has multiple through-holes, with one inlet corresponding to each single PCB board bearing space. The bottom surface of the inlet is flush with the top surface of the fixed clamping plate, and the PCB board is pushed into the single PCB board bearing space from the inlet for clamping and fixing.

[0011] Preferably, the inner wall of the outer ring is provided with a ring of horizontal LED light sources, which are used to illuminate the PCB board from the side. The upper and lower sides of the supporting component are provided with vertical LED light sources, which are used to illuminate the PCB board from the upper and lower sides.

[0012] Preferably, the horizontal LED light source and the vertical LED light source can emit light of different wavelengths.

[0013] Preferably, the detection component includes a support base, on the side of which a first detection component, a second detection component, and a third detection component are respectively disposed. A rotating shaft is connected to the center of the support base, and a driving mechanism is connected to the rotating shaft. The rotation of the rotating shaft drives the support base to rotate, so that the first detection component, the second detection component, and the third detection component can take turns facing the PCB board for detection.

[0014] Preferably, the support base is in the shape of a triangular prism, and the cross-section of the support base is an equilateral triangle.

[0015] Compared with existing technologies, the double-sided AOI inspection mechanism for PCB circuit boards of the present invention has three clamping components arranged in a triangular shape within the single PCB board bearing space. Two of the three clamping components are located on the inner sidewall of the outer ring, and one of the three clamping components is located on the outer sidewall of the inner ring. The clamping components are used to fix the PCB board at three points. After the PCB board is fixed at three points by the clamping components, the rest of the PCB board is in a suspended state, thus avoiding hard contact between the components on the PCB board and other parts, effectively reducing damage to the PCB board during inspection. The triangular distribution of the three clamping components provides good stability after fixing the PCB board at three points, fully meeting the inspection requirements. [Attached Image Description]

[0016] Figure 1This is a schematic diagram of the double-sided AOI inspection mechanism for PCB circuit boards according to the present invention;

[0017] Figure 2 This is a schematic diagram of the support component of the double-sided AOI inspection mechanism for PCB circuit boards according to the present invention;

[0018] Figure 3 This is a schematic diagram of the inspection components of the double-sided AOI inspection mechanism for PCB circuit boards according to the present invention.

Detailed Implementation Methods

[0019] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are for illustrative purposes only and are not intended to limit the invention.

[0020] It should be noted that in the embodiments of the present invention, all directional indications (such as up, down, left, right, front, back, etc.) are limited to relative positions on the specified view, rather than absolute positions.

[0021] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0022] Please see Figures 1 to 3 The present invention provides a double-sided AOI inspection mechanism for PCB circuit boards, comprising a support component 10 and at least two inspection components 20, wherein the at least two inspection components 20 are respectively disposed on the upper and lower sides of the support component 10, the support component 10 is used to support and fix the PCB board, and the at least two inspection components 20 are used to perform double-sided inspection on the PCB board.

[0023] The supporting component 10 includes an inner ring 11 and an outer ring 12, which are connected as a whole by a supporting frame 15. The outer ring 12 surrounds the inner ring 11, forming a PCB board supporting space between the inner ring 11 and the outer ring 12. The PCB board supporting space is divided into four single PCB board supporting spaces 13 by the supporting frame 15, and one PCB board can be fixed in each single PCB board supporting space 13. The detection component 20 is located on the upper and lower sides of the PCB board supporting space.

[0024] The four single PCB board carrying spaces 13 are continuous in the horizontal direction, and the support frame 15 only divides the four single PCB board carrying spaces 13 in the vertical direction, so as to reflect that the detection component 20 detects the PCB boards in different single PCB board carrying spaces 13.

[0025] Three clamping assemblies 14 are arranged in a triangular shape within the single PCB board bearing space 13. Two of the three clamping assemblies 14 are located on the inner sidewall of the outer ring 12, and one of the three clamping assemblies 14 is located on the outer sidewall of the inner ring 11. The clamping assemblies 14 are used to fix the PCB board at three points. After the PCB board is fixed at three points by the clamping assemblies 14, the rest of the PCB board is in a suspended state, thus avoiding hard contact between the components on the PCB board and other parts, effectively reducing damage to the PCB board during testing. The triangular arrangement of the three clamping assemblies 14 provides good stability after fixing the PCB board at three points, fully meeting the testing requirements.

[0026] The clamping assembly 14 includes a fixed clamping plate and a movable clamping plate. The movable clamping plate is located above the fixed clamping plate, and a clamping micro-actuator is connected to the movable clamping plate. The clamping micro-actuator controls the movable clamping plate to lift and lower to achieve clamping and releasing of the PCB board.

[0027] The outer ring 12 has multiple through-holes 16 on its side. Each single PCB board carrying space 13 corresponds to one inlet 16. The bottom surface of the inlet 16 is flush with the top surface of the fixed clamping plate. The PCB board is pushed into the single PCB board carrying space 13 from the inlet 16 for clamping and fixing, which facilitates the rapid loading and inspection of the PCB board.

[0028] The inner wall of the outer ring 12 is provided with a ring of horizontal LED light sources, which are used to illuminate the PCB board from the side. The upper and lower sides of the support component 10 are provided with vertical LED light sources, which are used to illuminate the PCB board from the upper and lower sides. The horizontal and vertical LED light sources are used to illuminate the PCB board from all directions without blind spots, which can better capture defects and achieve more accurate detection.

[0029] The LED horizontal light source and the LED vertical light source can emit light of different wavelengths. Using light of different wavelengths for detection can reveal specific defects on or inside the material surface.

[0030] The detection component 20 includes a support base 21, which is in the shape of a triangular prism and has an equilateral triangle cross-section.

[0031] The support base 21 is provided with a first detection component 23, a second detection component 24 and a third detection component 25 on its side. A rotating shaft 22 is connected to the axis of the support base 21. The rotating shaft 22 is connected to a driving mechanism. The rotation of the rotating shaft 22 drives the support base 21 to rotate, so that the first detection component 23, the second detection component 24 and the third detection component 25 can take turns facing the PCB board for detection.

[0032] The first detection component 23 includes a high-resolution camera and a lens. The lens is used in conjunction with the high-resolution camera. The lens affects the image quality and factors such as focal length, aperture size, and optical distortion correction need to be considered.

[0033] The first detection component 23 includes an image acquisition card, which is connected to a high-resolution camera and is used to transmit image data captured by the high-resolution camera to a computer or other data processing system.

[0034] The first detection component 23 is used to achieve high-resolution imaging, including the following steps:

[0035] Step A1, Image Acquisition:

[0036] Images of the target are captured using a high-resolution camera, which may include a single image or a sequence of images.

[0037] Step A2, Image Processing:

[0038] The acquired images undergo further processing, including denoising, enhancement, filtering, and feature extraction.

[0039] Step A3, Data Analysis:

[0040] The processed images are analyzed to extract useful information and perform tasks such as measurement, classification, and recognition.

[0041] Step A4, result verification:

[0042] Verify the accuracy and reliability of the imaging results, determine whether the detection results are OK, and make adjustments and optimizations if necessary.

[0043] High-resolution imaging can capture minute details and features, providing clearer images and increasing their usability and readability, especially when viewed at magnification. Because the image contains more pixels, it can provide richer data information, which is helpful for subsequent analysis and processing. High-resolution imaging helps reduce blur and artifacts in the image, improving image quality. High-resolution imaging can quickly and accurately inspect products, reducing the need for manual inspection and improving production efficiency.

[0044] The second detection component 24 includes a laser source, a scanning head, and a photodetector. The laser source emits a laser beam and can be one of a solid-state laser, a gas laser, a semiconductor laser, or a fiber laser. The scanning head includes a rotating prism or mirror to form a scanning line of the laser beam in space. The photodetector receives the laser light reflected from the surface of the object and converts it into an electrical signal.

[0045] The second detection component 24 is used to perform laser scanning, including the following steps:

[0046] Step B1, laser emission:

[0047] A laser beam is emitted, which can be continuous or pulsed. The laser beam is then shaped into scan lines in space by rotating mirrors or scanning prisms.

[0048] Step B2, Reflection from the object's surface:

[0049] When a laser beam shines on the surface of an object, it is reflected according to the shape of the object.

[0050] Step B3, Receive reflected light:

[0051] Use a photodetector or other type of sensor to receive the reflected laser light.

[0052] Step B4, Position Detection:

[0053] The location of the reflection point in space is determined based on the time when the reflected light is received and the angular position of the scanning mechanism.

[0054] Step B5, Data Acquisition:

[0055] As the scan line moves, data is continuously collected to form point clouds or contour lines.

[0056] Step B6, Data Processing:

[0057] The collected point cloud data is processed, including filtering, noise reduction, and data fusion.

[0058] Step B7, 3D Reconstruction:

[0059] A 3D model of an object is generated using point cloud data and a surface reconstruction algorithm.

[0060] Step B8, Texture Mapping:

[0061] If needed, the texture information of the object's surface can be mapped onto the 3D model.

[0062] Step B9, Post-processing:

[0063] Post-processing such as smoothing and optimization is performed on the reconstructed model to improve its quality.

[0064] Laser scanning can be used to measure dimensions such as trace width, spacing, and hole diameter on PCBs, providing high-precision measurement results. For PCBs with three-dimensional features, such as raised components or recessed holes, laser scanning can acquire their three-dimensional morphology. Laser scanning can inspect the quality and consistency of solder joints, such as their height, shape, and volume. Laser scanning can be used to confirm the accuracy of component placement and whether they are correctly positioned according to design specifications. Laser scanning can detect cracks, gaps, or other physical defects on PCBs. Before wave soldering or selective soldering, laser scanning can inspect the distribution and amount of solder paste.

[0065] Laser scanning offers highly accurate measurements, making it ideal for PCB inspection where dimensional precision is critical. Laser scanning is non-contact, causing no physical damage to the PCB or its components. Its high speed makes it suitable for real-time inspection on high-speed production lines. Laser scanning can be used in various production environments and is highly resistant to ambient light interference. Laser scanning systems are easily integrated with automated production lines, enabling unattended automated inspection. It can simultaneously inspect both 2D and 3D features of the PCB. The data generated by laser scanning is standardized, facilitating subsequent data processing and analysis. The laser scanning head can be adjusted to accommodate PCBs of different sizes and shapes.

[0066] The third detection component 25 includes a projector, a camera, a light source controller, an image acquisition card, a synchronization controller, and a calibration device.

[0067] The projector is used to project specific light patterns (such as stripes, grids, or coded patterns) onto the surface of an object, and can be a DLP (Digital Light Processing) projector or an LCD projector.

[0068] The light source controller is used to control the brightness and on / off state of the projector to adapt to different scanning environments.

[0069] The synchronization controller is used to ensure that the projector and camera work in sync to obtain accurate 3D data.

[0070] The calibration device is used to calibrate the camera and projector, determining their geometric parameters and relative positions.

[0071] The third detection component 25 is used to perform structured light scanning, including the following steps:

[0072] Step C1, Projection Light Mode:

[0073] Use a projector to project specific light patterns, such as stripes, grids, or coded patterns, onto the surface of the object being measured.

[0074] Step C2 Image Capture:

[0075] A camera is used to capture the reflected light pattern from the surface of an object at a specific angle. Due to the unevenness of the object's surface, the reflected light pattern will be distorted.

[0076] Step C3 Image Processing:

[0077] The captured images are processed to extract the features of the deformed light patterns.

[0078] Step C4: Triangulation

[0079] Based on the relative positions of the projector and camera, and the distortion of the light pattern, the spatial coordinates of each point on the object's surface are calculated using the principle of triangulation.

[0080] Step C5: Point cloud generation

[0081] Through the above steps C1-C4, three-dimensional point cloud data of the object surface can be generated.

[0082] Step C5 Surface Reconstruction:

[0083] Point cloud data is used to generate a 3D surface model of an object through surface reconstruction algorithms, such as Poisson reconstruction.

[0084] Step C6 Texture Mapping:

[0085] An optional step is to map the captured image textures onto the reconstructed 3D model to obtain more detailed visual effects.

[0086] Post-processing in step C7:

[0087] Post-processing such as smoothing and denoising is performed on the reconstructed model to improve its quality.

[0088] Structured light scanning provides three-dimensional topographic information of PCB board surfaces, aiding in the detection of component height, solder joint volume, and surface unevenness. Structured light technology achieves micron-level measurement accuracy, making it suitable for detecting fine features on PCB boards. Its high-resolution image acquisition capabilities allow structured light scanning to capture minute defects and details on PCB boards. As a non-contact inspection method, structured light scanning avoids the risk of physical damage to the PCB board or its components. It can quickly scan PCB boards, making it suitable for rapid inspection needs on production lines. It is suitable for inspecting PCB boards with complex shapes or irregular surfaces. It can simultaneously detect multiple features on the PCB board, such as component positions, solder joint quality, and trace width. Structured light scanning technology is easily integrated into automated inspection systems, enabling unattended automated inspection. It is suitable for inspecting various materials, including metals, plastics, and other materials commonly used in PCB manufacturing. Structured light scanning systems can operate under various environmental conditions and have good anti-interference capabilities. Structured light scanning systems can be adjusted and expanded to meet different inspection needs.

[0089] Compared with the prior art, the double-sided AOI inspection mechanism for PCB circuit boards of the present invention has three clamping components 14 arranged in a triangular shape within the single PCB board bearing space 13. Two of the three clamping components 14 are located on the inner sidewall of the outer ring 12, and one of the three clamping components 14 is located on the outer sidewall of the inner ring 11. The clamping components 14 are used to fix the PCB board at three points. After the PCB board is fixed at three points by the clamping components 14, the rest of the PCB board is in a suspended state, thus avoiding hard contact between the components on the PCB board and other parts, effectively reducing damage to the PCB board during inspection. The triangular arrangement of the three clamping components 14 provides good stability after fixing the PCB board at three points, fully meeting the inspection requirements.

[0090] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. Any modifications, equivalent substitutions and improvements made within the concept of the present invention should be included within the patent protection scope of the present invention.

Claims

1. A double-sided AOI inspection mechanism for PCB circuit boards, characterized in that, It includes a support component and at least two sets of detection components, wherein the at least two sets of detection components are respectively disposed on the upper and lower sides of the support component, the support component is used to support and fix the PCB board, and the at least two sets of detection components are used to perform double-sided detection on the PCB board; The load-bearing component includes an inner ring and an outer ring, which are connected as a whole by a support frame. The outer ring is arranged around the inner ring, and a PCB board load-bearing space is formed between the inner ring and the outer ring. The PCB board load-bearing space is divided into four single PCB board load-bearing spaces by the support frame, and a PCB board can be fixed in each single PCB board load-bearing space. Three clamping components are provided in the single PCB board bearing space. The three clamping components are distributed in a triangular shape. Two of the three clamping components are located on the inner side wall of the outer ring, and one of the three clamping components is located on the outer side wall of the inner ring. The clamping components are used to fix the PCB board at three points. After the PCB board is fixed at three points by the clamping components, the rest of the PCB board is in a suspended state. Each set of the detection components includes a support base, on the side of which a first detection component, a second detection component, and a third detection component are respectively arranged. A rotating shaft is connected to the center of the support base, and a driving mechanism is connected to the rotating shaft. The rotation of the rotating shaft drives the support base to rotate, so that the first detection component, the second detection component, and the third detection component take turns facing the PCB board for detection. The four single PCB board bearing spaces are continuous in the horizontal direction, and the support frame only divides the four single PCB board bearing spaces in the vertical direction. The clamping assembly includes a fixed clamping plate and a movable clamping plate. The movable clamping plate is located above the fixed clamping plate, and a clamping micro-actuator is connected to the movable clamping plate. The clamping micro-actuator controls the lifting and lowering of the movable clamping plate to achieve clamping and releasing of the PCB board. The PCB board is placed between the inner ring and the outer ring. The clamping components on the outer side wall of the inner ring abut against the outside and the clamping components on the inner side wall of the outer ring abut against the inside, forming a counter-fixing force system, so that the rest of the PCB board is in a suspended state. The first detection component includes an image acquisition card, which is connected to a high-resolution camera and is used to transmit image data captured by the high-resolution camera to a computer or other data processing system; The first detection component is used to achieve high-resolution imaging, including the following steps: Step A1, Image Acquisition: Capture target images using a high-resolution camera, including single images or image sequences; Step A2, Image Processing: The acquired images are further processed, including denoising, enhancement, filtering, and feature extraction; Step A3, Data Analysis: Analyze the processed images, extract useful information, and perform measurement, classification, and recognition tasks; Step A4, result verification: Verify the accuracy and reliability of the imaging results, determine whether the detection results are OK, and make adjustments and optimizations accordingly; The second detection component is used to perform laser scanning, including the following steps: Step B1, laser emission: A laser beam is emitted by a laser, which may be continuous or pulsed, and the laser beam is shaped into a scanning line in space by a rotating mirror or scanning prism. Step B2, Reflection from the object's surface: When a laser beam shines on the surface of an object, it is reflected according to the shape of the object. Step B3, Receive reflected light: Use a photodetector or other type of sensor to receive the reflected laser light; Step B4, Position Detection: The location of the reflection point in space is determined based on the time when the reflected light is received and the angular position of the scanning mechanism. Step B5, Data Acquisition: As the scan line moves, data is continuously acquired to form point clouds or contour lines; Step B6, Data Processing: The collected point cloud data is processed; Step B7, 3D Reconstruction: A 3D model of an object is generated using point cloud data and a surface reconstruction algorithm. Step B8, Texture Mapping: Map the texture information of the object's surface onto a 3D model; The third detection component is used to perform structured light scanning, including the following steps: Step C1, Projection Light Mode: Use a projector to project a specific light pattern onto the surface of the object being tested; Step C2 Image Capture: Use a camera to capture the reflected light patterns from the surface of an object from a specific angle; Step C3 Image Processing: The captured images are processed to extract the deformed light pattern features; Step C4: Triangulation Based on the relative positions of the projector and camera, and the distortion of the light pattern, the spatial coordinates of each point on the object's surface are calculated using the principle of triangulation. Step C5: Point cloud generation Through the above steps C1-C4, three-dimensional point cloud data of the object surface is generated; Step C5 Surface Reconstruction: Point cloud data is used to generate a 3D surface model of an object through a surface reconstruction algorithm.

2. The double-sided AOI inspection mechanism for PCB circuit boards as described in claim 1, characterized in that, The outer ring side has multiple through-holes, and each single PCB board bearing space corresponds to one inlet. The bottom surface of the inlet is flush with the top surface of the fixed clamping plate. The PCB board is pushed into the single PCB board bearing space from the inlet for clamping and fixing.

3. The double-sided AOI inspection mechanism for PCB circuit boards as described in claim 1, characterized in that, The inner wall of the outer ring is provided with a ring of horizontal LED light sources, which are used to illuminate the PCB board from the side. The upper and lower sides of the supporting component are provided with vertical LED light sources, which are used to illuminate the PCB board from the upper and lower sides.

4. The double-sided AOI inspection mechanism for PCB circuit boards as described in claim 3, characterized in that, Both the horizontal and vertical LED light sources can emit light of different wavelengths.

5. The double-sided AOI inspection mechanism for PCB circuit boards as described in claim 1, characterized in that, The support base is in the shape of a triangular prism, and the cross-section of the support base is an equilateral triangle.

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