A PCB board blind hole detection machine and detection method

Abstract

The present invention provides a PCB board blind hole detection machine and detection method. Lines on a line board are scanned, and then the horizontal offset angle is determined according to the comparison between the scanned lines and preset lines, and the vertical offset angle is determined according to the angle between the emission point of a linear array scanning camera and the axis of the linear array scanning camera on a detection frame. Then, the position of the linear array scanning camera is adjusted according to the horizontal offset angle and the vertical offset angle, so that the scanning plane of the linear array scanning camera is flush with the plane of a workbench, and then the position of a light source module is adjusted by scanning the bright and dark areas of the blind hole image, so that the light source module can irradiate the blind hole to a greater extent; and then the PCB board is placed and then positioned, so that the problem of inaccurate detection caused by improper installation of the linear array scanning camera and improper installation of the PCB board can be prevented.

Description

Technical Field

[0001] The present invention relates to the technical field of PCB board detection, and in particular to a PCB board blind hole detection machine and a detection method. Background Art

[0002] PCB (Printed Circuit Board), also known as printed circuit board in Chinese, is an important electronic component, a support for electronic components and a carrier for electrical interconnection. Because it is made by electronic printing, it is called a "printed" circuit board.

[0003] During the production process of PCB boards, the dimensions of key parts on the PCB boards need to be measured. Currently, the market uses area array cameras for PCB board measurement. Area array cameras are used to identify defects on the surface of PCB boards. However, area array cameras have a small field of view and are only suitable for measuring smaller PCB boards. They are not applicable to large-area PCB boards.

[0004] For example, the Chinese patent application number is CN202311699246.8, and the publication date is 2024.04.16. It discloses a PCB board rapid measurement device, which belongs to the field of measurement technology. It solves the problem of slow measurement of larger PCB boards by area array cameras in the prior art. The PCB board rapid measurement device includes a measuring platform and a measuring unit for placing the PCB board, the measuring unit includes a linear array camera and an area array camera, the measuring unit is arranged on an X-direction moving mechanism, and the measuring platform is arranged on a Y-direction moving mechanism, and the moving direction of the X-direction moving mechanism is perpendicular to the moving direction of the Y-direction moving mechanism. This document uses a linear array camera to perform rapid scanning measurement of the key dimensions of the PCB board, drives the PCB board to move at high speed through a motion module, and cooperates with a high-resolution line scan camera to scan, so as to realize the measurement of the key dimensions of the PCB board, which is suitable for rapid measurement of large-size PCB boards.

[0005] The above document discloses measuring a PCB board by a line array camera, and scanning is achieved by only moving the line array camera in the horizontal and vertical directions. However, if the installation position of the line array camera and the PCB board does not correspond, for example, the center of the PCB board and the line array camera do not correspond, or the PCB board and the scanning plane of the line array camera are not arranged parallel, the line array camera will not be able to accurately scan the PCB board. For example, when the PCB board is not placed accurately on the workbench, the position of the scanned blind hole will deviate, so that the blind hole on the PCB board cannot be accurately scanned. In addition, since the blind hole on the PCB board is small, the camera needs to illuminate the blind hole with a light source when scanning to ensure that the line array camera can better scan the blind hole. Summary of the invention

[0006] The object of the present invention is to provide a PCB board blind hole detection machine and detection method, which can reliably position the PCB board, thereby reliably detecting the blind holes on the PCB board.

[0007] To achieve the above object, the present invention provides a detection method of a PCB board blind hole detection machine, which realizes detection by a PCB board detection machine, wherein the PCB board detection machine includes a workbench, a detection frame, a linear array scanning camera, a positioning device and a light source module, and the specific steps include:

[0008] (1) Place the line board on the workbench;

[0009] (2) The line array scanning camera scans the lines on the line board to obtain a scanned image of the lines on the line board.

[0010] (3) By comparing the line scan image with the lines on the preset actual line board, the angle between the lines in the line scan image and the lines on the actual line board is obtained, and the horizontal offset angle of the line array scan camera is determined based on the angle.

[0011] (4) The vertical offset angle of the line scan camera is determined by the angle between the position of the line scan camera's emission point on the plane below the detection mechanism and the axis of the line scan camera.

[0012] (5) The line scan camera is adjusted according to the horizontal offset angle of the line scan camera and the vertical angle between the axis of the line scan camera and the horizontal plane.

[0013] (6) Adjust the position of the light source module according to the size of the bright and dark areas of the blind hole image obtained by the linear array scanning camera.

[0014] (7) Place the PCB on the workbench and secure it.

[0015] (8) The positioning device scans the positioning points of the PCB board, and then drives the detection mechanism to move to the positioning hole based on the positioning points obtained by the scan, so that the scanning coordinates of the linear array scanning camera correspond to the pre-set PCB board coordinates.

[0016] (9) The inspection mechanism scans the blind holes on the PCB board and compares the blind hole image information of the current PCB board with the blind hole image information of the pre-set standard PCB board to determine whether the blind holes on the PCB board are qualified.

[0017] The above method first scans the lines on the line board, then determines the horizontal offset angle according to the comparison between the scanned lines and the preset lines, and determines the vertical offset angle according to the angle between the emission point of the line array scanning camera and the axis of the line array scanning camera on the detection frame, and then adjusts the position of the line array scanning camera according to the horizontal offset angle and the vertical offset angle, so that the scanning plane of the line array scanning camera is flush with the plane of the workbench, and then adjusts the position of the light source module by scanning the bright and dark areas of the blind hole image, so that the light source module can irradiate the blind hole to a greater extent, and then puts the PCB board to be tested, and then locates the starting position on the PCB board, and then moves the line array scanning camera to the starting position on the PCB board, so that the line array scanning camera can be positioned, and at the same time, the light source module can irradiate the blind hole at a larger angle, and then the PCB board is placed and then positioned, which can prevent the problem of inaccurate detection caused by improper installation of the line array scanning camera and improper installation of the PCB board.

[0018] Furthermore, step (4) includes: (41) determining the emission point in the axial direction of the linear scanning camera in the detection plane, and then determining the position of the emission point of the linear array scanning camera on the plane below the detection mechanism, (42) comparing the emission point in the axial direction of the linear scanning camera with the position of the emission point of the linear array scanning machine on the plane below the detection mechanism to determine the distance difference between the two, and then determining the vertical offset angle of the linear array scanning camera based on the distance between the center of the preset linear scanning camera and the plane.

[0019] The above setting can determine the vertical offset angle of the line scan camera by the difference between the point emitted in the preset axis direction and the position of the actual emission point, which is convenient for calculation.

[0020] Furthermore, step (5) specifically includes:

[0021] S1 adjusts the verticality between the first adjustment component and the horizontal plane of the workbench.

[0022] S11 installs the first adjustment mounting plate on the first adjustment mounting shaft.

[0023] S12: rotating the first adjusting screw and the second adjusting screw so that the first adjusting screw and the second adjusting screw are close to each other and clamp the first adjusting block so that the first adjusting mounting plate is fixed.

[0024] S13: Rotate the first adjusting screw and the second adjusting screw in opposite directions according to the vertical angle of the linear array scanning camera, so that the first adjusting mounting plate is perpendicular to the horizontal plane of the workbench.

[0025] S2 adjusts the parallelism between the scanning line of the linear array scanning camera and the front surface line of the workbench.

[0026] S23 adjusts the third adjusting screw and the fourth adjusting screw to make the second mounting plate rotate in the opposite direction to adjust the horizontal offset angle of the linear array scanning camera, so that the third adjusting screw and the fourth adjusting screw are close to each other and clamp the second adjusting block to fix the second adjusting mounting plate.

[0027] Furthermore, step (6) includes: (61) comparing the bright and dark areas of the blind hole image with the bright and dark areas of the preset blind hole image; (62) if the dark area of ​​the blind hole image is larger than the dark area of ​​the preset blind hole image, increasing the tilt angle between the light source module and the linear array scanning camera; if the dark area of ​​the blind hole image is smaller than the dark area of ​​the preset blind hole image, decreasing the tilt angle between the light source module and the linear array scanning camera.

[0028] The above arrangement can more reliably enable the light source module to illuminate the blind hole by adjusting the tilt angle between the light source module and the linear array scanning camera.

[0029] Furthermore, step (9) includes: (91) if the difference between the current PCB board blind hole image information and the preset standard PCB board blind hole image information is within a preset difference range, it means that the current PCB board blind hole is qualified.

[0030] (92) If the difference between the current PCB board blind hole image information and the preset standard PCB board blind hole image information is not within the preset difference range, it means that the current PCB board blind hole is unqualified.

[0031] With the above arrangement, when it is detected that the blind hole image information and the preset image information are within a preset tolerance range, the blind hole is determined to be qualified, and the detection method is simple and reliable.

[0032] Furthermore, the inspection mechanism also includes a re-inspection camera, which is installed on the inspection frame through a re-inspection bracket. After step (92), step (10) is also included. If the current PCB board blind hole is unqualified, the re-inspection camera is driven to move to the unqualified blind hole position for further inspection.

[0033] The above settings, by setting up the re-inspection camera, can further refine the inspection of unqualified blind holes, thereby ensuring the accuracy of the inspection.

[0034] The present invention also provides a PCB board blind hole detection machine, the PCB board blind hole detection machine comprises a frame, a workbench is arranged on the frame, a detection mechanism is arranged above the workbench, the detection mechanism is arranged on the frame through a moving module, and the moving module drives the detection mechanism to move along the two side directions and the two end directions of the workbench; the detection mechanism comprises a detection frame, an adjustment device, a linear array scanning camera, a positioning device and a light source module, the detection frame is arranged on a second moving module, the linear array scanning camera is arranged on the detection frame through an adjustment device, the adjustment device is used to adjust the horizontal and vertical angles of the scanning plane of the linear array scanning camera, and a light source module is arranged on the detection frame below the linear array scanning camera; the light source module is detachably arranged on the detection frame, the detection end of the linear array scanning camera corresponds to the workbench, and a positioning device is also arranged on the detection frame, and the axis of the positioning device is arranged parallel to the axis of the linear array scanning camera.

[0035] The above setting, by setting a linear array scanning camera, drives the linear array scanning camera to move along the workbench through the moving module, thereby ensuring that the PCB board can be completely scanned, thereby ensuring that the blind holes of the PCB board can be detected. In addition, the scanning plane of the linear array scanning camera can be adjusted in the horizontal and vertical directions through the adjustment device, the starting point of the PCB board is adjusted through the positioning device, and the irradiation range of the light source module is adjusted through the light source module, thereby ensuring the range of the irradiation range of the linear camera, thereby ensuring the accuracy of the detection.

[0036] Furthermore, the light source module includes a mounting seat, a coaxial light source module and a side light source module, the coaxial light source module includes a coaxial light emitting body and a lens assembly, the coaxial light emitting body light source is arranged on one side of the mounting seat, the lens assembly includes one or more first lenses, fourth lenses, and fifth lenses, the first lenses and the second lenses are symmetrically arranged relative to the axis of the coaxial light emitting body, the first lens is tilted to the coaxial light source module, and the fifth lens is tilted to the axis of the coaxial light source module. The side light source module is arranged on the mounting seat and is located below the fifth lens, and the light emitted by the coaxial light source module is reflected by the first lens and then reflected by the fifth lens onto the object to be measured. The mounting seat is a hollow cavity structure, and a through groove is arranged on the upper surface of the mounting seat, the through groove is arranged on the fourth lens, the fifth lens is arranged below the fourth lens, and the fifth lens is tilted to the fourth lens, and the scanning end of the linear array scanning camera is located above the through groove.

[0037] With the above arrangement, the linear array scanning camera scans the PCB board on the workbench through the through slot. When the PCB board needs to be supplemented with brightness, the PCB board is illuminated by arranging light sources on both sides of the through slot, so that the blind holes on the PCB board can be easily scanned. At the same time, the light source module is provided with a coaxial light source module and a measuring light source module to provide light in different directions to meet the needs of different objects to be measured. The light source emitted by the coaxial light source enters the object to be measured after being reflected by the first lens and the fifth lens. Then the side light source module can illuminate the object to be measured from the side to eliminate shadows. The coaxial light source module and the side light source module are arranged in a mounting seat to form a closed area, which helps to reduce light scattering and external light interference. The coaxial light source module is guided by the lens assembly to achieve the expected lighting effect.

[0038] Furthermore, the adjustment device includes a first adjustment component and a second adjustment component, the first adjustment component is arranged on the detection frame, the second adjustment component is arranged on the first adjustment component, the linear array scanning camera is arranged on the second adjustment component, the first adjustment component is used to adjust the verticality of the second adjustment component and the horizontal plane of the workbench; the second adjustment component is used to adjust the parallelism of the scanning line of the linear array scanning camera and the front end surface line of the workbench.

[0039] The above arrangement adjusts the position of the linear array scanning camera through the adjusting device, thereby improving the accuracy of blind hole detection.

[0040] Furthermore, the first adjusting component includes a first adjusting mounting plate, a first adjusting mounting shaft, a first adjusting block, a first adjusting plate, a first adjusting screw and a second adjusting screw. The first adjusting mounting shaft is arranged on the detection frame. The center of the first adjusting mounting plate is provided with a mounting hole corresponding to the first adjusting mounting shaft. The first adjusting mounting plate is arranged on the first adjusting mounting shaft. A first adjusting plate is provided on the detection frame on one side of the first adjusting mounting plate. A first adjusting groove is provided on the first adjusting plate. A first adjusting block is provided on one side of the first adjusting mounting plate. The first adjusting block is located in the first adjusting groove. First adjusting screws and second adjusting screws are respectively provided on the first adjusting plates on both sides of the first adjusting block. A threaded hole is provided on the first adjusting plate. The first adjusting screw and the second adjusting screw are located in the threaded hole. The first adjusting screw and the second adjusting screw are close to each other and abut against both sides of the first adjusting block.

[0041] The second adjustment component includes a second adjustment mounting plate, a second adjustment connecting plate, a second adjustment block, a second adjustment plate, a third adjustment screw and a fourth adjustment screw. The second adjustment connecting plate is arranged on the first adjustment mounting plate, a through hole is arranged in the center of the second adjustment connecting plate, and a second adjustment mounting plate is arranged at the top of the first adjustment connecting plate. The linear array scanning camera is located below the first adjustment connecting plate and is connected to the first adjustment mounting plate through the through hole. A second adjustment plate is arranged on the second adjustment connecting plate at one end of the second adjustment mounting plate, a second adjustment groove is arranged on the second adjustment plate, and a second adjustment block is arranged at one end of the second adjustment mounting plate. The second adjustment block is located in the second adjustment groove, and a third adjustment screw and a fourth adjustment screw are respectively arranged on the second adjustment plates on both sides of the second adjustment block, and a threaded hole is arranged on the second adjustment plate. The third adjustment screw and the fourth adjustment screw are located in the threaded hole, and the third adjustment screw and the fourth adjustment screw are close to each other and abut against both sides of the second adjustment block.

[0042] The above arrangement, through the arrangement of the first adjusting screw and the second adjusting screw, allows the first adjusting screw and the second adjusting screw to be rotated so that the first adjusting mounting plate can be rotated when fine-tuning of the first adjusting mounting plate is required, thereby realizing vertical angle adjustment of the first adjusting mounting plate, and through the arrangement of the third adjusting screw and the fourth adjusting screw, allows the second adjusting mounting plate to be rotated when fine-tuning of the linear array scanning camera is required, thereby realizing rotation angle adjustment of the linear array scanning camera. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] Figure 1 It is a schematic diagram of the structure of the present invention.

[0044] Figure 2 for Figure 1 Enlarged schematic diagram at point A in the middle.

[0045] Figure 3 This is a simple schematic diagram showing that the vertical line of the first adjustment mounting plate of the present invention is in a vertical state with the end surface of the workbench.

[0046] Figure 4 It is a simple schematic diagram of the first adjustment of the offset of the mounting plate of the present invention.

[0047] Figure 5 It is a simple schematic diagram showing that the scanning lines emitted by the line scan camera of the present invention are in a parallel state with the standard lines set on the workbench.

[0048] Figure 6 FIG. 1 is a simple schematic diagram of the deviation of the scan line emitted by the line scan camera of the present invention.

[0049] Figure 7 for Figure 2 Enlarged view of point F in the middle.

[0050] Figure 8 It is the work flow chart of the present invention.

[0051] Fig. 9 It is a schematic structural diagram of the first adjustment component of the present invention.

[0052] Fig.10 This is an adjustment flow chart of the first adjustment mounting plate of the present invention.

[0053] Fig.11 This is a flow chart of adjusting the linear scan camera of the present invention.

[0054] Fig.12 It is a structural schematic diagram of the light source module in the present invention.

[0055] Fig.13 It is an exploded diagram of the light source module in the present invention.

[0056] Fig.14 It is a schematic diagram of adjusting the side light source illuminant in the present invention. DETAILED DESCRIPTION

[0057] The present invention is further described in detail below in conjunction with specific implementation modes.

[0058] Embodiment 1.

[0059] like Figure 1-Figure 7 , Fig. 9 as well as Figure 12-13 As shown, a PCB board blind hole detection machine includes a frame 1, a workbench 2 is arranged on the frame 1, the workbench is installed on the frame 1 through a first moving module 11, a detection mechanism 3 is arranged above the workbench 2, the detection mechanism 3 is arranged on the frame 1 through a second moving module 12, the second moving module 12 drives the detection mechanism 3 to move along the two sides of the frame 1, and the first moving module 11 drives the workbench 2 to move along the two ends of the frame 1. In this embodiment, the first moving module 11 and the second moving module 12 are devices that drive another device to slide along a guide rail through a driving device such as a motor or a cylinder, which is specifically a prior art and will not be repeated here.

[0060] In this embodiment, a limit bar (not shown in the figure) for limiting the PCB board is provided on the outer edge of the workbench 2. The limit bar is provided to position and limit the PCB board when it is placed on the workbench.

[0061] like Figure 1 and Figure 2As shown, the detection mechanism 3 includes a detection frame 31, an adjustment device 4, a linear scan camera 32, a positioning device 33 and a light source module 34. The detection frame 31 is arranged on the second moving module 12, and the linear scan camera 32 is arranged on the detection frame 31 through the adjustment device 4. A light source module 34 is arranged on the detection frame 31 below the linear scan camera 32; the detection end of the linear scan camera 32 corresponds to the workbench 2, and a positioning device 33 is also arranged on the detection frame 31. By arranging the linear scan camera 32, the linear scan camera 32 is driven by the second moving module to move along the workbench 2, thereby ensuring that all PCB boards can be scanned, thereby ensuring that the blind holes of the PCB board can be detected.

[0062] like Figure 12-13 As shown, the light source module includes a mounting seat 343, a coaxial light source module 341 and a side light source module 342. The coaxial light source module 341 includes a coaxial light emitting body 011 and a lens assembly 012. The lens assembly 012 includes one or more first lenses 0121 and second lenses 0122. The first lens 0121 is arranged on one side of the coaxial light emitting body 011 light source, the second lens 0122 is arranged on the other side of the first lens 0121, the third lens 0123 is arranged on one side of the side light emitting body light source 012, the coaxial light source module 341 is arranged on one side of the mounting seat 343, and the side light source module 342 is arranged in the middle of the mounting seat 343.

[0063] A through groove 3431 is provided on the upper surface of the mounting base 3, and the light source module includes a fourth lens 031 and a fifth lens 033. The fourth lens 031 is fixedly provided on the upper surface of the mounting base 343, and a semi-transparent and semi-reflective lens is obliquely provided below the fourth lens 031. The mounting base 343 is provided with an observation window. Generally, a linear scanning camera 32 is placed above the through groove 3431. The linear scanning camera 32 can shoot the object to be measured through the fourth lens 031, and a semi-transparent and semi-reflective lens is provided below the fourth lens 031 to reflect a part of the light emitted by the coaxial light emitting body 011, and then emit it to the object to be measured after passing through the semi-transparent and semi-reflective lens, and a part of the light emitted by the coaxial light emitting body 011 can pass through the semi-transparent and semi-reflective mirror to reach the shooting device, so that the shooting device can obtain a clearer image.

[0064] Mounting holes 3432 are arranged opposite to each other on both sides of the mounting seat 343, and a gap is arranged between the mounting holes 3432 and the side light source illuminator 021. The mounting holes 3432 include a first mounting hole 34321 and a second mounting hole 34322. The first mounting hole 34321 and the second mounting hole 34322 are symmetrically arranged relative to the axial direction of the mounting seat 3432, and the first mounting hole 34321 and the second mounting hole 34322 are connected. The first mounting hole 34321 and the second mounting hole 34322 are arranged downward and outward. Two side light source illuminators 021 are arranged in the mounting hole 3432. Specifically, the side light source illuminator 021 can be detachably mounted on the mounting seat by providing a side light source illuminator mounting piece 02111 on the side light source illuminator 021. The mounting seat 343 is provided with a mounting hole 3432, and the two side light source illuminators 34321 can be tilted and fixedly arranged in the mounting hole 3432.

[0065] In this embodiment, the first lens 0121 and the second lens 0122 are reflective lenses, and the third lens 0123 is a focusing lens.

[0066] The light source module is provided with a coaxial light source module 341 and a side light source module 342 which can provide light in different directions to meet the needs of different objects to be measured. The coaxial light source module 341 can illuminate the center of the object to be measured, and the side light source module 342 can illuminate the object to be measured from the side to eliminate shadows. The coaxial light source module 341 and the side light source module 342 are arranged in a mounting base 343 to form a closed area, which helps to reduce light scattering and external light interference. The light emitted by the coaxial light source module 341 is guided by using the lens assembly 012 to achieve the desired lighting effect.

[0067] The linear array scanning camera 32 scans the PCB board on the workbench 2 through the through slot 3431. When the PCB board needs to be supplemented with brightness, the PCB board is illuminated by setting light sources on both sides of the through slot 341, so that the blind holes on the PCB board can be easily scanned.

[0068] The positioning device 33 includes a positioning camera, and the positioning camera is installed on the detection frame 31 through a positioning bracket 331. By setting the positioning camera, it is convenient to locate the center of the PCB board and to scan the blind hole.

[0069] The detection mechanism 3 further includes a re-inspection camera 35, which is mounted on the detection frame 31 via a re-inspection bracket 351. By providing the re-inspection camera 35, it is convenient to re-inspect the blind hole, thereby increasing the accuracy of blind hole detection.

[0070] like Figure 2-Figure 6As shown, the adjusting device 4 includes a first adjusting component 41 and a second adjusting component 42, the first adjusting component 41 is arranged on the detection frame 31, the second adjusting component 42 is arranged on the first adjusting component 41, the linear array scanning camera 32 is arranged on the second adjusting component 42, the first adjusting component 41 is used to adjust the verticality α between the second adjusting component 42 and the horizontal plane of the workbench 2; the second adjusting component 42 is used to adjust the parallelism β between the scanning line of the linear array scanning camera 32 and the front end surface line of the workbench 2.

[0071] The above arrangement adjusts the position of the linear array scanning camera through the adjusting device, thereby improving the accuracy of blind hole detection.

[0072] like Figure 2-Figure 4 As shown, the first adjustment component 41 includes a first adjustment mounting plate 411, a first adjustment mounting shaft 412, a first adjustment block 413, a first adjustment plate 414, a first adjustment screw 415 and a second adjustment screw 416. The first adjustment mounting shaft 412 is arranged on the detection frame 31. The center of the first adjustment mounting plate 411 is provided with a mounting hole corresponding to the first adjustment mounting shaft 412. The first adjustment mounting plate 411 is arranged on the first adjustment mounting shaft 412. The detection frame 31 on one side of the first adjustment mounting plate 411 is provided with a first adjustment plate 414. 14 is provided with a first adjustment slot 4141, a first adjustment block 413 is provided on one side of the first adjustment mounting plate 411, the first adjustment block 413 is located in the first adjustment slot 4141, a first adjustment screw 415 and a second adjustment screw 416 are respectively provided on the first adjustment plate 414 on both sides of the first adjustment block 413, a threaded hole (not shown in the figure) is provided on the first adjustment plate 414, the first adjustment screw 415 and the second adjustment screw 416 are located in the threaded hole, and the first adjustment screw 415 and the second adjustment screw 416 are close to each other and abut against both sides of the first adjustment block 413. Through the provision of the first adjustment screw 415 and the second adjustment screw 416, when it is necessary to fine-tune the first adjustment mounting plate 411, the first adjustment screw 415 and the second adjustment screw 416 are rotated so that the first adjustment mounting plate 411 can be rotated, thereby realizing the vertical angle adjustment of the first adjustment mounting plate 411.

[0073] like Figure 2 , 5 - Figure 7As shown, the second adjustment component 42 includes a second adjustment mounting plate 421, a second adjustment connecting plate 422, a second adjustment block 423, a second adjustment plate 424, a third adjustment screw 425 and a fourth adjustment screw 426. The second adjustment connecting plate 422 is arranged on the first adjustment mounting plate 411. A through hole is provided in the center of the second adjustment connecting plate 422. A second adjustment mounting plate 421 is provided at the top of the first adjustment connecting plate 422. After the second adjustment mounting plate 421 is clamped at the upper end of the first adjustment connecting plate 422, it can be fine-tuned on the first adjustment connecting plate 422. In this embodiment, a mounting hole is provided on the second adjustment mounting plate 421, and a first mounting hole corresponding to the mounting hole is provided on the first adjustment connecting plate 422. Screws are provided in the mounting hole and the first mounting hole. When fine-tuning, the screws in the mounting hole and the first mounting hole are loosened, and then the position is adjusted and locked to achieve fine-tuning and fixation. The linear array scanning camera 32 is located below the first adjusting connecting plate 422 and is fixedly connected to the first adjusting mounting plate 421 through a through hole. A second adjusting plate 424 is provided on the second adjusting connecting plate 422 at one end of the second adjusting mounting plate 421, and a second adjusting groove 4241 is provided on the second adjusting plate 424. A second adjusting block 423 is provided at one end of the second adjusting mounting plate 421. The second adjusting block 423 is located in the second adjusting groove 4241. A third adjusting screw 425 and a fourth adjusting screw 426 are respectively provided on the second adjusting plates 424 on both sides of the second adjusting block 423. A threaded hole (not shown in the figure) is provided on the second adjusting plate 424. The third adjusting screw 425 and the fourth adjusting screw 426 are located in the threaded hole. The third adjusting screw 425 and the fourth adjusting screw 426 are close to each other and abut against both sides of the second adjusting block 423. By setting the third adjusting screw 425 and the fourth adjusting screw 426, when the linear array scanning camera 32 needs to be fine-tuned, the third adjusting screw 425 and the fourth adjusting screw 426 are rotated to allow the second adjustment mounting plate 421 to rotate, thereby achieving the rotation angle adjustment of the linear array scanning camera 32.

[0074] Embodiment 2.

[0075] like Figure 1-Figure 13 As shown, a detection method of a PCB board blind hole detection machine includes the following specific steps:

[0076] (1) A line board (not shown) is placed on a workbench 2; lines or blind holes arranged in a matrix are arranged on the line board;

[0077] (2) The line array scanning camera 32 scans the lines on the line board to obtain a scanned image of the lines on the line board.

[0078] (3) By comparing the line scan image with the preset lines on the actual line board, the angle between the lines in the line scan image and the lines on the actual line board is obtained, and the horizontal offset angle of the line scan camera is determined according to the angle. In this embodiment, a part of the lines on the line board can be scanned first. For example, if there are 3 lines on the line board, they can be scanned one by one, thereby reducing the amount of data processed by the line scan camera.

[0079] (4) The vertical offset angle of the line scan camera is determined by the angle between the position of the emission point of the line scan camera 32 on the plane below the detection mechanism and the axis of the line scan camera 32.

[0080] (5) The line scan camera is adjusted according to the horizontal offset angle of the line scan camera and the vertical angle between the axis of the line scan camera and the horizontal plane.

[0081] (6) Adjust the position of the light source module according to the size of the bright and dark areas of the blind hole image obtained by the linear array scanning camera 32.

[0082] (7) Place the PCB board on workbench 2 and fix it.

[0083] (8) The positioning device 33 scans the positioning point of the PCB board, and then drives the detection mechanism 3 to move to the positioning hole based on the positioning point obtained by scanning, so that the scanning coordinates of the linear array scanning camera correspond to the preset PCB board coordinates. In this embodiment, a positioning point is set on the PCB board, and the positioning device scans the positioning point on the PCB board, and then compares the positioning point with the preset starting point of the linear array scanning camera. If they are not at the same point, the coordinates of the positioning point are set as the starting point of the linear array scanning camera, and then the linear array scanning camera is moved to the positioning point to start scanning. The linear array scanning camera can locate each point to the coordinate point on the workbench after scanning a point. This belongs to the prior art and will not be repeated here.

[0084] (9) The detection mechanism 3 scans the blind holes on the PCB board and compares the blind hole image information of the current PCB board with the blind hole image information of the pre-set standard PCB board to determine whether the blind holes on the PCB board are qualified.

[0085] Wherein, step (4) comprises: (51) determining the point b emitted in the axial direction of the linear scanning camera 32 in the detection plane, and then determining the position b1 of the point emitted by the linear array scanning camera 32 on the plane below the detection mechanism, (52) comparing the point emitted in the axial direction of the linear scanning camera with the position of the point emitted by the linear array scanning machine on the plane below the detection mechanism to determine the distance difference between the two, and then determining the vertical offset angle A of the linear array scanning camera according to the distance between the preset center of the linear scanning camera and the plane. In this embodiment, the distance difference D1 between the point preset in the detection plane and the point measured by the linear array scanning machine can be measured by a rangefinder, and then the distance between the preset center of the linear scanning camera and the detection plane can be set by a distance detector at the center of the detection frame, and then the distance D between the center of the detection frame and the detection plane can be measured, and then the vertical offset angle A of the linear array scanning camera can be calculated by arctan (D1 / D).

[0086] Wherein, step (5) specifically includes:

[0087] S1 adjusts the verticality between the first adjusting component 41 and the horizontal plane of the workbench 2.

[0088] S11: Install the first adjustment mounting plate 411 on the first adjustment mounting shaft 412.

[0089] S12 rotates the first adjusting screw 415 and the second adjusting screw 416 so that the first adjusting screw 415 and the second adjusting screw 416 are close to each other and clamp the first adjusting block 413 so that the first adjusting mounting plate 411 is fixed.

[0090] S13 reversely rotates the first adjusting screw 415 and the second adjusting screw 416 according to the vertical angle of the line scan camera, so that the first adjusting mounting plate 411 is perpendicular to the horizontal plane of the workbench 2 .

[0091] Step S13 specifically includes: in this embodiment, if Figure 3 As shown, at this time, the axis a of the first adjustment mounting plate 411 is perpendicular to the straight line b where the upper end surface of the workbench 2 is located. If the angle of the first adjustment mounting plate 411 is offset, as shown in FIG. Figure 4 As shown, the first adjustment mounting plate 411 is offset to the left. At this time, the first adjustment screw 415 is unscrewed away from the first adjustment block 413, and the second adjustment screw 416 is screwed so that the second adjustment screw 416 pushes the first adjustment block 413 to move in the direction of the first adjustment screw 415, thereby driving the first adjustment mounting plate 411 to rotate with the first adjustment mounting shaft 412 as the fulcrum so that the first adjustment mounting plate 411 is offset to the right and returned to normal (as shown in FIG. Figure 4As shown by the arrow in the middle, when the vertical line a of the first adjustment mounting plate 411 is perpendicular to the end surface b of the workbench 2, the first adjustment screw 415 and the second adjustment screw 416 are tightened at the same time, thereby clamping and fixing the first adjustment block 413, thereby realizing the vertical angle adjustment of the first adjustment mounting plate 411.

[0092] S2 adjusts the parallelism between the scanning line of the linear scan camera and the front surface line of the workbench.

[0093] S23 adjusts the third adjusting screw and the fourth adjusting screw so that the second mounting plate rotates in the opposite direction to adjust the horizontal offset angle of the linear scan camera so that the third adjusting screw and the fourth adjusting screw are close to each other and clamp the second adjusting block so that the second adjusting mounting plate is fixed.

[0094] Step S23 specifically includes: In this embodiment, Figure 5 As shown, at this time, the line c scanned by the line scan camera 32 is parallel to the line d of the actual line board (that is, the line of the line scan image can overlap with the line of the actual line board). If the rotation angle of the line scan camera 32 is offset, such as Figure 6 As shown, the rotation angle of the line scan camera 32 is offset to the rear side. At this time, an angle is formed between the line c and the line d. At this time, the fourth adjusting screw 426 is unscrewed away from the second adjusting block 423, and the third adjusting screw 425 is screwed so that the third adjusting screw 425 pushes the second adjusting block 423 to move in the direction of the fourth adjusting screw 426, thereby driving the second adjusting mounting plate 421 to rotate so that the second adjusting mounting plate 421 is offset to the front side and returned to normal (as shown in FIG. Figure 6 As shown by the arrow in the middle, when the scanning line of the linear array scanning camera 32 is parallel to the standard line, the third adjusting screw 425 and the fourth adjusting screw 426 are tightened at the same time, thereby clamping and fixing the second adjusting block 423, thereby achieving the adjustment of the rotation angle of the linear array scanning camera 32.

[0095] Wherein, step (6) includes: (61) comparing the bright and dark areas of the blind hole image with the bright and dark areas of the preset blind hole image; (62) if the bright area of ​​the blind hole image is larger than the bright area of ​​the preset blind hole image, increasing the inclination angle of the light source module and the linear array scanning camera; if the bright area of ​​the blind hole image is smaller than the bright area of ​​the preset blind hole image, decreasing the inclination angle of the light source module and the linear array scanning camera; after each adjustment, comparing the bright and dark areas of the blind hole image with the bright and dark areas of the preset blind hole image again, and adjusting again according to the comparison situation until the bright and dark areas of the blind hole image match the bright and dark areas of the preset blind hole image.

[0096] like Fig.14As shown, if the size of the blind hole set on the detection line board or the PCB board to be tested matches the size of the preset blind hole, for example, the actually measured bright area S2 of the blind hole is smaller than the preset bright area S1 of the blind hole, then a side light source illuminant 021 with an increased inclination angle with the mounting seat will be manually replaced. After the inclination angle between the side light source illuminant 021 and the axis of the linear array scanning camera is increased, in this embodiment, the light source module has an adjustment angle range of less than 10 degrees, which belongs to fine-tuning. Since a gap is provided between the mounting hole and the side light source illuminant, fine-tuning can be achieved by tightening or loosening the fixing bolts between the side light source illuminants, or the side light source illuminant within the mounting range of the mounting hole can be replaced to achieve adjustment, so that the emitted light source can illuminate a larger blind hole area, thereby increasing the detection accuracy.

[0097] Wherein, step (9) includes: (91) if the difference between the current PCB board blind hole image information and the preset standard PCB board blind hole image information is within a preset difference range, it means that the current PCB board blind hole is qualified. In this embodiment, the preset difference range is 10%.

[0098] (92) If the difference between the current PCB board blind hole image information and the preset standard PCB board blind hole image information is not within the preset difference range, it means that the current PCB board blind hole is unqualified.

[0099] In step (10), if the blind hole of the current PCB board is unqualified, the re-inspection camera is driven to move to the position of the unqualified blind hole for further inspection. When it is detected that the blind hole of the PCB board is unqualified, the controller determines the position of the unqualified blind hole. The coordinate point can be determined by the coordinate system obtained by scanning with the linear scanning camera, and then the positioning device is moved to the position of the determined coordinate point to achieve further scanning.

[0100] The working principle of the present invention is as follows: by adjusting the detection mechanism 3, the linear array scanning camera can be perpendicular to the workbench, and the scanning line of the linear array scanning camera 32 can be kept parallel to the front end surface line of the workbench 2, so that when the blind holes are scanned and detected, the position of each scanned blind hole can be determined, thereby maintaining a high measurement accuracy when the blind holes of the current PCB board are subsequently compared with the standard blind holes, and at the same time, by adjusting the verticality of the linear array scanning camera, it is ensured that the linear array scanning camera can scan the bottom of the blind hole, avoiding the problem of inaccurate depth measurement of the blind hole caused by the linear array scanning camera 32 only being able to scan the inner wall of the blind hole due to angle deviation.

Claims

1. A method for detecting blind holes in a PCB board, which is realized by a PCB board detection machine, and is characterized by: The PCB board inspection machine includes a frame, a workbench, an inspection frame, a linear array scanning camera, a positioning device and a light source module. The specific steps include: (1) Place the line board on the workbench; (2) The line array scanning camera scans the lines on the line board to obtain a scanned image of the lines on the line board; (3) By comparing the line scan image with the lines on the preset actual line board, the angle between the lines in the line scan image and the lines on the actual line board is obtained, and the horizontal offset angle of the line scan camera is determined according to the angle; (4) Determine the vertical offset angle of the line scan camera by taking the position of the line scan camera emission point on the plane below the detection mechanism and the angle between the line scan camera axis; (5) adjusting the line scan camera according to the horizontal offset angle of the line scan camera and the vertical angle between the axis of the line scan camera and the horizontal plane; (6) Adjust the position of the light source module according to the size of the bright and dark areas of the blind hole image obtained by the linear array scanning camera; (7) Place the PCB board on the workbench and fix it; (8) The positioning device scans the positioning points of the PCB board, and then drives the detection mechanism to move to the positioning hole according to the positioning points obtained by the scan, so that the scanning coordinates of the linear array scanning camera correspond to the pre-set coordinates of the PCB board; (9) The testing mechanism scans the blind holes on the PCB board and compares the blind hole image information of the current PCB board with the blind hole image information of the pre-set standard PCB board to determine whether the blind holes on the PCB board are qualified; The light source module includes a mounting seat, a coaxial light source module and a side light source module. The coaxial light source module includes a coaxial light emitting body and a lens assembly. The coaxial light emitting body light source is arranged on one side of the mounting seat. The lens assembly includes more than one first lens, fourth lens, and fifth lens. The first lens and the second lens are symmetrically arranged relative to the axis of the coaxial light emitting body. The first lens is tilted with the coaxial light source module, and the fifth lens is tilted with the axis of the coaxial light source module. The side light source module is arranged on the mounting seat and is located below the fifth lens. The light emitted by the coaxial light source module is reflected by the first lens and then reflected by the fifth lens onto the object to be measured. The mounting seat is a hollow cavity structure. A through groove is arranged on the upper surface of the mounting seat, and a fourth lens is arranged on the through groove. The fifth lens is arranged below the fourth lens, and the fifth lens is tilted with the fourth lens. The scanning end of the linear array scanning camera is located above the through groove.

2. A PCB board blind hole detection method according to claim 1, characterized in that: Step (4) includes: (41) determining the emission point in the axial direction of the linear scanning camera in the detection plane, and then determining the position of the emission point of the linear array scanning camera on the plane below the detection mechanism, (42) comparing the emission point in the axial direction of the linear scanning camera with the position of the emission point of the linear array scanning machine on the plane below the detection mechanism to determine the distance difference between the two, and then determining the vertical offset angle of the linear array scanning camera based on the distance between the center of the preset linear scanning camera and the plane.

3. A PCB board blind hole detection method according to claim 1, characterized in that: Step (5) specifically includes: S1 adjusts the verticality between the first adjustment component and the horizontal plane of the workbench; S11: installing the first adjustment mounting plate on the first adjustment mounting shaft; S12: rotating the first adjusting screw and the second adjusting screw so that the first adjusting screw and the second adjusting screw are close to each other and clamp the first adjusting block so that the first adjusting mounting plate is fixed; S13: rotating the first adjusting screw and the second adjusting screw in opposite directions according to the vertical angle of the line scan camera, so that the first adjusting mounting plate is perpendicular to the horizontal plane of the workbench; S2 adjusts the parallelism between the scanning line of the linear scan camera and the front surface line of the workbench; S23 adjusts the third adjusting screw and the fourth adjusting screw to make the second mounting plate rotate in the opposite direction to adjust the horizontal offset angle of the linear array scanning camera, so that the third adjusting screw and the fourth adjusting screw are close to each other and clamp the second adjusting block to fix the second adjusting mounting plate.

4. A PCB board blind hole detection method according to claim 1, characterized in that: Step (6) includes: (61) comparing the bright and dark areas of the blind hole image with the bright and dark areas of the preset blind hole image; (62) if the dark area of ​​the blind hole image is larger than the dark area of ​​the preset blind hole image, increasing the tilt angle between the light source module and the linear array scanning camera; if the dark area of ​​the blind hole image is smaller than the dark area of ​​the preset blind hole image, decreasing the tilt angle between the light source module and the linear array scanning camera.

5. A PCB board blind hole detection method according to claim 1, characterized in that: Step (9) includes: (91) if the difference between the current PCB board blind hole image information and the preset standard PCB board blind hole image information is within a preset difference range, it means that the current PCB board blind hole is qualified; (92) If the difference between the current PCB board blind hole image information and the preset standard PCB board blind hole image information is not within the preset difference range, it means that the current PCB board blind hole is unqualified.

6. A PCB board blind hole detection method according to claim 5, characterized in that: The inspection mechanism also includes a re-inspection camera, which is installed on the inspection frame through a re-inspection bracket. After step (92), step (10) is also included. If the current PCB board blind hole is unqualified, the re-inspection camera is driven to move to the unqualified blind hole position for further inspection.

7. A PCB board blind hole detection machine, comprising a frame, a workbench is arranged on the frame, a detection mechanism is arranged above the workbench, the detection mechanism is arranged on the frame through a moving module, and the moving module drives the detection mechanism to move along the two side directions and the two end directions of the workbench; characterized in that: The detection mechanism includes a detection frame, an adjustment device, a linear scan camera, a positioning device and a light source module. The detection frame is arranged on the second moving module. The linear scan camera is arranged on the detection frame through the adjustment device. The adjustment device is used to adjust the horizontal and vertical angles of the scanning plane of the linear scan camera. A light source module is arranged on the detection frame below the linear scan camera; the light source module is detachably arranged on the detection frame, the detection end of the linear scan camera corresponds to the workbench, and a positioning device is also arranged on the detection frame, and the axis of the positioning device is arranged parallel to the axis of the linear scan camera; the light source module includes a mounting seat, a coaxial light source module and a side light source module, the coaxial light source module includes a coaxial light emitter and a lens assembly, the coaxial light emitter The light source of the light body is arranged on one side of the mounting seat, and the lens assembly includes more than one first lens, fourth lens, and fifth lens. The first lens and the second lens are symmetrically arranged relative to the axis of the coaxial light emitting body, the first lens and the coaxial light source module are tilted, and the fifth lens and the axis of the coaxial light source module are tilted. The side light source module is arranged on the mounting seat and is located below the fifth lens. The light emitted by the coaxial light source module is reflected by the first lens and then reflected by the fifth lens onto the object to be measured. The mounting seat is a hollow cavity structure, and a through groove is arranged on the upper surface of the mounting seat, and the fourth lens is arranged on the through groove. The fifth lens is arranged below the fourth lens, and the fifth lens is tilted with the fourth lens, and the scanning end of the linear array scanning camera is located above the through groove.

8. A PCB board blind hole detection machine according to claim 7, characterized in that: The adjustment device includes a first adjustment component and a second adjustment component, the first adjustment component is arranged on the detection frame, the second adjustment component is arranged on the first adjustment component, the linear array scanning camera is arranged on the second adjustment component, the first adjustment component is used to adjust the verticality of the second adjustment component and the horizontal plane of the workbench; the second adjustment component is used to adjust the parallelism of the scanning line of the linear array scanning camera and the front end surface line of the workbench.

9. A PCB board blind hole detection machine according to claim 8, characterized in that: The first adjustment component comprises a first adjustment mounting plate, a first adjustment mounting shaft, a first adjustment block, a first adjustment plate, a first adjustment screw and a second adjustment screw, the first adjustment mounting shaft being arranged on the detection frame, a mounting hole corresponding to the first adjustment mounting shaft being arranged at the center of the first adjustment mounting plate, the first adjustment mounting plate being arranged on the first adjustment mounting shaft, a first adjustment plate being arranged on the detection frame on one side of the first adjustment mounting plate, a first adjustment groove being arranged on the first adjustment plate, a first adjustment block being arranged on one side of the first adjustment mounting plate, the first adjustment block being located in the first adjustment groove, a first adjustment screw and a second adjustment screw being arranged on the first adjustment plates on both sides of the first adjustment block respectively, a threaded hole being arranged on the first adjustment plate, the first adjustment screw and the second adjustment screw being located in the threaded hole, the first adjustment screw and the second adjustment screw being close to each other and abutting against both sides of the first adjustment block; The second adjustment component includes a second adjustment mounting plate, a second adjustment connecting plate, a second adjustment block, a second adjustment plate, a third adjustment screw and a fourth adjustment screw. The second adjustment connecting plate is arranged on the first adjustment mounting plate, a through hole is arranged in the center of the second adjustment connecting plate, and a second adjustment mounting plate is arranged at the top of the first adjustment connecting plate. The linear array scanning camera is located below the first adjustment connecting plate and is connected to the first adjustment mounting plate through the through hole. A second adjustment plate is arranged on the second adjustment connecting plate at one end of the second adjustment mounting plate, a second adjustment groove is arranged on the second adjustment plate, and a second adjustment block is arranged at one end of the second adjustment mounting plate. The second adjustment block is located in the second adjustment groove, and a third adjustment screw and a fourth adjustment screw are respectively arranged on the second adjustment plates on both sides of the second adjustment block, and a threaded hole is arranged on the second adjustment plate. The third adjustment screw and the fourth adjustment screw are located in the threaded hole, and the third adjustment screw and the fourth adjustment screw are close to each other and abut against both sides of the second adjustment block.

Images