Circuit board photographing detection device

Abstract

The invention belongs to the technical field of circuit boards, and relates to a circuit board photographing detection device which is characterized in that a circuit board front face detection position and a temporary storage position are sequentially arranged on a circuit board conveying track, a circuit board back face detection position and an unqualified product storage position are arranged on one side of the temporary storage position, and a first camera and a first light supplementing lamp set of the first camera are arranged on the upper side of the front face detection position; a vacuum suction cup conveying mechanism is arranged on the upper sides of the temporary storage position, the back face detection position and the unqualified product storage position, a second camera and a second light supplementing lamp set of the second camera are arranged on the lower side of the back face detection position, and the circuit board is taken and placed among the temporary storage position, the back face detection position and the unqualified product storage position through the vacuum suction cup conveying mechanism. The images, shot by the first camera and the second camera, of the front face and the back face of the circuit board are transmitted to the controller and compared with standard images pre-stored in the controller, compared qualified products and unqualified products are processed respectively, and the circuit board detection device has the advantages that detection work is optimized, detection efficiency is improved, and the circuit board detection device is suitable for an assembly line of the circuit board.

Description

Technical Field

[0001] This invention belongs to the field of circuit board technology, and in particular relates to a circuit board photographic inspection device. Background Technology

[0002] Circuit board production is mostly carried out using assembly line operations, with some processing done manually. Whether it is manual or machine assembly, due to various reasons, situations such as missing parts, incorrect parts, incorrect polarity, and reversed, open circuits, and short circuits of integrated circuits may occur. Therefore, the testing work after the circuit board is assembled is extensive and complicated. Summary of the Invention

[0003] The purpose of this invention is to provide a circuit board photographic inspection device that optimizes the inspection process and improves inspection efficiency.

[0004] The objective of this invention is achieved as follows: A circuit board photographic inspection device includes a worktable. A circuit board transport track is provided on one side of the worktable. A front-side inspection position and a temporary placement position are sequentially arranged on the transport track. A back-side inspection position and a defective product storage position are provided on one side of the temporary placement position. A first camera capable of photographing the front of the circuit board and its first supplementary light group are provided above the front-side inspection position. A vacuum suction cup transport mechanism is provided above the temporary placement position, the back-side inspection position, and the defective product storage position. A second camera capable of photographing the back of the circuit board and its second supplementary light group are provided below the back-side inspection position. The vacuum suction cup transport mechanism can... The circuit boards on the temporary placement position of the conveyor track are sequentially moved to the back inspection position, the temporary placement position, or the defective product storage position. The images of the front and back of the circuit board captured by the first and second cameras are transmitted to the controller. After being compared with the standard images stored in the controller, if the comparison results are consistent, the circuit board is judged as qualified and is sent back to the temporary placement position by the vacuum suction cup conveyor mechanism and then sent out by the circuit board conveyor track. If the comparison results are inconsistent, the circuit board is judged as defective and is sent to the defective product storage position by the vacuum suction cup conveyor mechanism. The defective product is a circuit board with incomplete coating of conformal adhesive on the circuit board being inspected.

[0005] As a further optimization of the above technical solution, circuit board placement racks are fixed at intervals on the conveying track. The circuit board placement racks are provided with positioning blocks, two or more positioning columns, and detection holes for sensing sensors to detect whether there are circuit boards. Lifting cylinders that drive the circuit board placement racks at the front detection position and the temporary placement position are provided on the worktable.

[0006] As a further optimization of the above technical solution, a first gantry is provided at the front detection position of the conveying track. A first camera is installed on a first bracket centrally located on the crossbeam above the first gantry, which can capture images of the circuit board at the front detection position. The first bracket is provided with a vertical strip hole. The first camera is fixed to the first bracket with adjustable height through the strip hole. The lens of the first camera is set downward and can capture the front image of the circuit board paused at the front detection position.

[0007] As a further optimization of the above technical solution, the first supplementary light group is installed on both sides of the first bracket via the second bracket. The second bracket is provided with a vertical strip hole for adjusting the installation height of the first supplementary light group. The first bracket is installed on the crossbeam above the first gantry through the strip hole with adjustable height. The second bracket is provided with an arc-shaped hole for adjusting the illumination angle of the first supplementary light group. The first supplementary light group is installed on the second bracket with adjustable angle through the arc hole. The first supplementary light group can provide supplementary lighting when taking images of the circuit board paused at the front detection position.

[0008] As a further optimization of the above technical solution, the first and second supplementary light groups have the same structure, both of which have multiple rows and columns of LED lights arrayed on the front of the lamp holder, each LED light is installed in its own lamp bowl, and all LED lights are covered with a light-diffusing plate.

[0009] As a further optimization of the above technical solution, two or more sensing sensors are respectively provided on the worktable where the front detection position, the temporary placement position and the back detection position are located. The sensing sensors are used to detect whether there is a circuit board on the front detection position, the temporary placement position and the back detection position and transmit the information to the controller so that the controller can control the next action.

[0010] As a further optimization of the above technical solution, the vacuum suction cup conveying mechanism includes a second gantry frame set on the workbench. The crossbeam above the second gantry frame is located above the temporary placement position, the back inspection position, and the defective product storage position. A first slider, driven by a power source, slides on a first slide rail set on the crossbeam of the second gantry frame. A vertical slide rail is set on the lower side of the first slider, and a first cylinder is fixed on the upper side. The piston rod of the first cylinder is connected to the second slider that slides on the vertical slide rail. The second slider is connected to an upper moving plate. Several vacuum suction cups capable of adhering to circuit boards are set on the lower surface of the lower moving plate. A three-dimensional buffer mechanism formed by springs is arrayed between the upper and lower moving plates. The elastic coefficient of the springs is 14-16 N / mm. The three-dimensional buffer mechanism has a non-linear damping compression stroke of 2±0.2 mm. The vacuum suction cups are connected to a solenoid valve, a vacuum tank, and a vacuum pump in sequence through conduits. The opening and closing of the solenoid valve is controlled by a controller to facilitate the adsorption or release of the circuit board.

[0011] As a further optimization of the above technical solution, the conveying track includes an outer track and an inner track that are parallel to each other. Two or more parallel lead screws and guide rods perpendicular to the outer track are provided on the fixed beams on the inner sides of the outer track and the inner track. A threaded sleeve fixed on the inner track is fitted onto the lead screw. The guide rod passes through the guide hole of the inner track. A servo motor fixed on the outer track drives all the lead screws to rotate through a synchronous belt and synchronous pulley assembly to drive the inner track to move closer to or away from the outer track. The outer track is fixed on the worktable, and the inner track and the fixed beam slide on the worktable.

[0012] As a further optimization of the above technical solution, a through hole is provided on the worktable at the back detection position. A vertical strip hole is provided on the third bracket fixed on the lower surface of the worktable on one side of the through hole. The second camera is fixed on the third bracket with adjustable height through the strip hole. The lens of the second camera is set upward and can capture the back image of the circuit board paused at the back detection position through the through hole.

[0013] As a further optimization of the above technical solution, a second supplementary light group is installed on the table surface on both sides of the through hole through a fourth bracket. The fourth bracket is provided with an arc-shaped hole for adjusting the illumination angle of the second supplementary light group. The second supplementary light group is installed on the fourth bracket at an adjustable angle through the arc-shaped hole. The second supplementary light group can provide supplementary lighting when taking images of the circuit board paused at the back detection position.

[0014] The advantages of this invention compared to the prior art are: 1. The first and second supplementary light groups of this invention are configured with adjustable illumination angles, which can accurately adjust the illumination range of circuit boards of different sizes and heights, resulting in good supplementary lighting effect. The first and second cameras are configured with adjustable heights, which are suitable for focusing and capturing images of circuit boards of different sizes and heights, resulting in high image clarity.

[0015] 2. This invention uses a first camera and a second camera to capture images of the front and back of the circuit board, which can accurately determine the installation position and soldering status of electronic components. Once missing, incorrect, reversed polarity components and integrated circuits, open circuits, short circuits, etc. are found, the circuit is immediately sent to the non-conforming product storage location and no further testing is required. This optimizes the testing process, reduces the workload of subsequent testing, and improves testing efficiency.

[0016] 3. This invention utilizes a dynamic matching technology for dual track spacing, based on a multi-screw transmission mechanism. It employs a servo motor to drive the bidirectional rotation of the multi-screw, and features an equidistant thread structure with a lead of 8mm. This allows the track spacing to be adjusted within a range of 50-200mm, making it suitable for the stable transport of circuit boards of different widths.

[0017] 4. The layout of the front inspection position and temporary placement position of the horizontally arranged circuit board, and the back inspection position and defective product storage position arranged vertically are reasonable, the equipment operates smoothly, forming a complete node of the circuit board assembly line, and can be connected to the operation process of the circuit board assembly line. Attached Figure Description

[0018] Figure 1 This is one of the three-dimensional schematic diagrams of the present invention.

[0019] Figure 2 This is the second three-dimensional schematic diagram of the present invention.

[0020] Figure 3 yes Figure 1 Enlarged view of part A.

[0021] Figure 4 yes Figure 1 Enlarged view of part B.

[0022] Figure 5 yes Figure 2 Enlarged view of part C.

[0023] Figure 6 yes Figure 2 Enlarged view of part D.

[0024] Figure 7 This is an enlarged view of the structure near the first camera and the first supplementary light group of the present invention.

[0025] Figure 8 This is an enlarged view of the structure near the vacuum suction cup conveying mechanism of the present invention.

[0026] Figure 9 This is a three-dimensional schematic diagram of a partial structure at the transport track.

[0027] Figure 10 This is a three-dimensional schematic diagram of a portion of the transmission structure of the conveyor track. Detailed Implementation

[0028] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. See also: Figures 1-10 : A circuit board photographic inspection device includes a worktable 10. A circuit board transport track 35 is provided on one side of the worktable 10. A front inspection position 11 and a temporary placement position 12 for the circuit boards are sequentially arranged on the transport track 35. A back inspection position 13 and a defective product storage position 14 for the circuit boards are provided on one side of the temporary placement position 12. A first camera 46 capable of photographing the front of the circuit board and its first supplementary light group 38 are provided above the front inspection position 11. The temporary placement position 12, the back inspection position 13, and the defective product storage position 14 are located above... A vacuum suction cup conveying mechanism is provided on the side. A second camera 26 and its second supplementary light group 30 are provided below the back detection position 13 to capture images of the back of the circuit board. The vacuum suction cup conveying mechanism can sequentially move the circuit board on the temporary placement position 12 of the conveying track 35 to the back detection position 13, the temporary placement position 12, or the defective product 16 storage position 14. The images of the front and back of the circuit board 15 captured by the first camera 46 and the second camera 26 are transmitted to the controller. After comparison with the standard images pre-stored in the controller, if the comparison results are consistent, the circuit board is judged to be a qualified product. The circuit board is returned to the temporary placement position 12 by the vacuum suction cup conveyor mechanism and then sent out by the circuit board conveyor track 35. If the comparison results are inconsistent, it is judged as a defective product 16 (a defective circuit board) and sent to the defective product 16 storage position 14 by the vacuum suction cup conveyor mechanism, thus realizing the rejection of defective products. The defective product is a circuit board with incomplete coating of conformal coating or a circuit board that should have been coated with conformal coating but was not. The qualified product is a circuit board with complete conformal coating or a circuit board that should have been coated with conformal coating. Circuit boards coated with conformal coating are used in various locations. Because the spectral or image information of products coated with and without conformal coating in captured images is easily identified, analyzed, measured, and processed by a computer (controller), the controller classifies and processes them according to whether they are qualified or unqualified. The conformal coating, also known as circuit board protective adhesive or coating adhesive, is a silicone-modified resin used to protect circuit boards and related equipment from harsh environments, thereby improving and extending product lifespan and ensuring safety and reliability during use. The conformal coating is applied to the surface of the circuit board, forming a thin, lightweight, and flexible film only 40-60 micrometers thick. It protects the circuit from damage under conditions such as those containing chemicals (e.g., fuel, coolant), vibration, moisture, salt spray, humidity, and high temperatures. Under these conditions, circuit boards may corrode, develop mold, and short circuit, leading to malfunctions in circuits without conformal coating. The protective film formed by conformal coating can effectively isolate and protect circuits from corrosion by chemicals, moisture and other contaminants, thereby improving the reliability of the circuit board, increasing its safety factor and ensuring its service life.

[0029] As a further optimization of the above technical solution, circuit board placement racks 33 are fixed at intervals on the conveying track 35. The circuit board placement racks 33 are provided with positioning blocks 34, two or more positioning posts 32, and detection holes 36 for sensing sensors 31 (such as magnetic induction sensors or photoelectric induction sensors) to detect the presence or absence of circuit boards 15. Lifting cylinders are provided on the worktables at the front detection position 11 and the temporary placement position 12 to drive the circuit board placement racks 33 at these positions to rise and fall. After the lifting cylinders drive the circuit board placement racks 33 to rise, they abut against the lower surface of the guide plate on the conveying track 35 to position the height of the circuit board, so as to facilitate the camera to focus and capture the image of the circuit board, and to facilitate the vacuum suction cup to accurately adsorb the circuit board, and to protect the conveying track 35 from impact after the vacuum suction cup descends.

[0030] As a further optimization of the above technical solution, a first gantry frame 40 is provided at the front detection position 11 of the conveying track 35. A first camera 46 is installed on a first bracket 44 centrally located on the crossbeam 49 above the first gantry frame 40. The first camera 46 can capture images of the circuit board on the front detection position 11. A vertical strip hole 45 is provided on the first bracket 44. The first camera 46 is fixed to the first bracket 44 with adjustable height through the strip hole 45. The lens 47 of the first camera 46 is set downward and can capture the front image of the circuit board 15 paused at the front detection position 11.

[0031] As a further optimization of the above technical solution, the first supplementary light group 38 is installed on both sides of the first bracket 44 through the second bracket 43. The second bracket 43 is provided with a vertical strip hole 42 for adjusting the installation height of the first supplementary light group 38. The first bracket 44 is installed on the crossbeam 49 above the first gantry frame 40 through the strip hole 45 for adjustable height. The second bracket 43 is provided with an arc hole 37 for adjusting the illumination angle of the first supplementary light group 38. The first supplementary light group 38 is installed on the second bracket 43 for adjustable angle through the arc hole 37. The first supplementary light group 38 can provide supplementary lighting when the circuit board 15 is paused at the front detection position 11 to capture images.

[0032] As a further optimization of the above technical solution, the first fill light group 38 and the second fill light group 30 have the same structure. Both have multiple rows and columns of LED lights 22 arrayed on the front of the lamp holder 23. Each LED light 22 is installed in its own lamp bowl. A light-diffusing plate is provided on the outer side of all LED lights 22. The first fill light group 38 and the second fill light group 30 are each provided with two groups. With the light-diffusing plate, the captured image can be ensured to be shadow-free.

[0033] As a further optimization of the above technical solution, two or more sensing sensors 31 are respectively provided on the worktable 10 where the front detection position 11, the temporary placement position 12 and the back detection position 13 are located. The sensing sensors 31 are used to detect whether there is a circuit board 15 on the front detection position 11, the temporary placement position 12 and the back detection position 13 and transmit the information to the controller so that the controller can control the next action.

[0034] As a further optimization of the above technical solution, the vacuum suction cup conveying mechanism includes a second gantry 53 mounted on the workbench 10. A crossbeam 17 above the second gantry 53 is located above the temporary placement position 12, the back inspection position 13, and the defective product 16 storage position 14. A first slide rail 55 mounted on the crossbeam 17 of the second gantry 53 is equipped with a first slider 56 driven by a power source. A vertical slide rail 50 is mounted on the lower side of the first slider 56, and a first cylinder 18 is fixed on its upper side. The piston rod of the first cylinder 18 is connected to a second cylinder 56 that slides on the vertical slide rail 50. On slider 19, an upper moving plate 57 is connected to the second slider 19. Several vacuum suction cups capable of adhering to circuit boards are provided on the lower surface of the lower moving plate 59. A three-dimensional buffer mechanism formed by springs 58 is arrayed between the upper and lower moving plates 57 and 59. The elastic coefficient of the springs 58 is 14-16 N / mm. The three-dimensional buffer mechanism has a non-linear damping compression stroke of 2±0.2 mm. The vacuum suction cups 51 are connected to a solenoid valve, a vacuum tank and a vacuum pump in sequence through conduits. The opening and closing of the solenoid valve is controlled by a controller to facilitate the adsorption or release of the circuit board.

[0035] As a further optimization of the above technical solution, the conveying track 35 includes an outer track 351 and an inner track 352 that are parallel to each other. Two or more parallel lead screws 61 and guide rods 62, perpendicular to the outer track, are installed on the fixed beam 60 inside the outer track 351 and the inner track 352. A threaded sleeve 63 fixed on the inner track 352 is fitted onto the lead screw 61. The guide rod 62 passes through the guide hole of the inner track 352. A servo motor 64 fixed on the outer track 351 drives all the lead screws 61 to rotate via a synchronous belt 66 and a synchronous pulley 65 assembly, thereby moving the inner track 352 closer to or away from the outer track, achieving fine-tuning of the track distance between the outer track 351 and the inner track 352. The outer track 351 is fixed on the worktable 10, and the inner track 352 and the fixed beam 60 slide on the worktable 10. The lead of the thread on the lead screw 61 is 8mm, and the adjustment range is 50-200mm. The action of the servo motor 64 is controlled by a controller.

[0036] As a further optimization of the above technical solution, a through hole 24 is provided on the table surface of the workbench 10 at the back detection position 13. A vertical strip hole 28 is provided on the third bracket 27 fixed on the lower surface of the table surface on one side of the through hole 24. The second camera 26 is mounted on the camera mounting base 29 and fixed on the third bracket 27 with adjustable height through the strip hole 28. The lens 25 of the second camera 26 is set upward and can capture the back image of the circuit board 15 paused at the back detection position 13 through the through hole 24.

[0037] As a further optimization of the above technical solution, a second supplementary light group 30 is installed on the table surface on both sides of the through hole 24 through a fourth bracket 20. The fourth bracket 20 is provided with an arc-shaped hole 21 for adjusting the illumination angle of the second supplementary light group 30. The second supplementary light group 30 is installed on the fourth bracket 20 at an adjustable angle through the arc-shaped hole 21. The second supplementary light group 30 can provide supplementary lighting when the circuit board 15 is paused at the back detection position 13 to capture images.

[0038] The working process of this invention is as follows: The circuit board 15 placed on the circuit board placement rack 33 on the circuit board conveying track 35 is moved to the front detection position 11 of the circuit board under the control of the controller. Simultaneously, the controller controls the first supplementary lighting group 38 to provide supplementary lighting, while the first camera 46 captures an image of the front of the circuit board at the front detection position 11 and transmits it to the controller for a first comparison with the standard image of the circuit board 15 pre-stored in the controller. Then, the controller controls the conveying track 35 to move the circuit board 15 to the temporary placement position 12. The controller then controls the vacuum suction cup 51 of the vacuum suction cup conveying mechanism to adhere to the circuit board 15 at this location and move it to the circuit board... At the back detection position 13, while the controller controls the second supplementary light group 30 to provide supplementary light, the second camera 26 captures an image of the back of the circuit board at the back detection position 13 and transmits it to the controller for a second comparison with the standard image stored in the controller. If the comparison results of the first and second comparisons are consistent, the product is judged as qualified and is sent back to the temporary placement position 12 by the vacuum suction cup conveying mechanism and then sent out to the next work station by the circuit board conveying track 35. If either comparison result is inconsistent, the product is judged as unqualified 16 and is sent to the unqualified product 16 storage position 14 by the vacuum suction cup conveying mechanism. The above actions are repeated to achieve continuous detection of the circuit board 15.

[0039] The standard image of the circuit board 15 pre-stored in the controller is a pre-shot image of the shape and position of electronic components, circuits and wires on the front and back of the circuit board. The defective product 16 of the circuit board is defined as one that does not conform to the standard image of the circuit board 15. For example, it may be missing, incorrect, reversed polarity of components and integrated circuits, open circuit, short circuit, etc.

[0040] The controller (computer) compares the standard image of the circuit board with the shape and position image of the circuit board 15 to be compared one by one. If the shape and position image of the circuit board 15 being tested is inconsistent with the standard image of the circuit board, it will be judged as a defective product 16. If they are all consistent, it will be judged as a qualified product. Missing parts, wrong parts, reversed polarity components and integrated circuits, open circuits, short circuits, etc. will all result in differences in shape and position from the standard image. These are also easily identified and processed by the controller (computer's image recognition system). This eliminates unnecessary circuit boards for the next step of inspection, optimizes and reduces the workload of the next step of inspection, and improves the efficiency of the inspection.

[0041] The above embodiments are only used to illustrate the technical solutions of the present invention, and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that simple substitutions or modifications can still be made to the technical solutions or technical features described in the foregoing embodiments, and these simple substitutions or modifications do not cause the essence of the corresponding technical solutions to deviate from the spirit and substance of the technical solutions of the embodiments of the present invention, and are still within the protection scope of the present invention.

Claims

1. A circuit board photographic inspection device, comprising a worktable, characterized in that: A circuit board conveying track is provided on one side of the workbench. A front inspection position and a temporary placement position are sequentially arranged on the conveying track. A back inspection position and a defective product storage position are arranged on one side of the temporary placement position. A first camera and its first supplementary light group are arranged above the front inspection position to capture images of the front of the circuit board. A vacuum suction cup conveying mechanism is arranged above the temporary placement position, the back inspection position, and the defective product storage position. A second camera and its second supplementary light group are arranged below the back inspection position to capture images of the back of the circuit board. The vacuum suction cup conveying mechanism can sequentially move the circuit board from the temporary placement position on the conveying track to the back inspection position, the temporary placement position, or the defective product storage position. The images of the front and back of the circuit board captured by the first and second cameras are transmitted to the controller. These images are compared with pre-stored standard images in the controller. If the comparison results match, the circuit board is judged as a qualified product and is sent back to the temporary placement position by the vacuum suction cup conveying mechanism and then sent out by the circuit board conveying track. If the comparison results do not match, the circuit board is judged as a defective product and is sent to the defective product storage position by the vacuum suction cup conveying mechanism. The defective product is a circuit board with incomplete application of conformal coating.

2. The circuit board photographic inspection device according to claim 1, characterized in that: Circuit board placement racks are fixed at intervals on the conveying track. The circuit board placement racks are equipped with positioning blocks, two or more positioning columns, and detection holes for sensors to detect the presence or absence of circuit boards. Lifting cylinders that drive the circuit board placement racks at the front detection position and temporary placement position are provided on the worktable.

3. The circuit board photographic inspection device according to claim 1, characterized in that: A first gantry is provided at the front detection position of the conveying track. A first camera is installed on a first bracket centrally located on the crossbeam above the first gantry. The first camera is capable of capturing images of the circuit board at the front detection position. The first bracket has a vertical strip hole. The first camera is fixed to the first bracket at an adjustable height through the strip hole. The lens of the first camera is set downward and can capture the front image of the circuit board paused at the front detection position.

4. The circuit board photographic inspection device according to claim 3, characterized in that: The first supplementary light group is mounted on both sides of the first bracket via the second bracket. The second bracket is provided with a vertical strip hole for adjusting the installation height of the first supplementary light group. The first bracket is mounted on the crossbeam above the first gantry frame with adjustable height through the strip hole. The second bracket is provided with an arc-shaped hole for adjusting the illumination angle of the first supplementary light group. The first supplementary light group is mounted on the second bracket with adjustable angle through the arc-shaped hole. The first supplementary light group can provide supplementary lighting when capturing images of the circuit board paused at the front detection position.

5. The circuit board photographic inspection device according to claim 1, characterized in that: The first and second fill light groups have the same structure, both of which have multiple rows and columns of LEDs arrayed on the front of the lamp holder, with each LED installed in its own lamp bowl, and all LEDs covered with a light-diffusing plate.

6. The circuit board photographic inspection device according to claim 1, characterized in that: The worktables where the front detection position, temporary placement position, and back detection position are located are each equipped with two or more sensing sensors. The sensing sensors are used to detect whether there is a circuit board on the front detection position, temporary placement position, and back detection position and transmit the information to the controller so that the controller can control the next action.

7. The circuit board photographic inspection device according to claim 1, characterized in that: The vacuum suction cup conveying mechanism includes a second gantry frame set on the workbench. The crossbeam above the second gantry frame is located above the temporary placement position, the back inspection position, and the defective product storage position. A first slider, driven by a power source, slides on a first slide rail set on the crossbeam of the second gantry frame. A vertical slide rail is set on the lower side of the first slider, and a first cylinder is fixed on the upper side. The piston rod of the first cylinder is connected to the second slider that slides on the vertical slide rail. The second slider is connected to an upper moving plate. Several vacuum suction cups capable of adhering to circuit boards are set on the lower surface of the lower moving plate. A three-dimensional buffer mechanism formed by springs is arrayed between the upper and lower moving plates. The elastic coefficient of the springs is 14-16 N / mm. The three-dimensional buffer mechanism has a non-linear damping compression stroke of 2±0.2 mm. The vacuum suction cups are connected to a solenoid valve, a vacuum tank, and a vacuum pump in sequence through conduits. The opening and closing of the solenoid valve is controlled by a controller to facilitate the adsorption or release of the circuit board.

8. The circuit board photographic inspection device according to claim 7, characterized in that: The conveying track includes an outer track and an inner track that are parallel to each other. Two or more parallel lead screws and guide rods are installed on the fixed beams on the inner sides of the outer and inner tracks, perpendicular to the outer track. A threaded sleeve fixed on the inner track is fitted onto the lead screw. The guide rod passes through the guide hole of the inner track. A servo motor fixed on the outer track drives all the lead screws to rotate through a synchronous belt and synchronous pulley assembly to move the inner track closer to or away from the outer track. The outer track is fixed on the worktable, and the inner track and the fixed beam slide on the worktable.

9. The circuit board photographic inspection device according to claim 1, characterized in that: A through hole is provided on the workbench at the back detection position. A vertical strip hole is provided on the third bracket fixed to the lower surface of the workbench on one side of the through hole. The second camera is fixed to the third bracket at an adjustable height through the strip hole. The lens of the second camera is set upward and can capture the back image of the circuit board paused at the back detection position through the through hole.

10. A circuit board photographic inspection device according to claim 9, characterized in that: On the platforms on both sides of the through hole, a second supplementary light group is installed by a fourth bracket. The fourth bracket is provided with an arc-shaped hole for adjusting the illumination angle of the second supplementary light group. The second supplementary light group is installed on the fourth bracket at an adjustable angle through the arc-shaped hole. The second supplementary light group can provide supplementary lighting when taking images of the circuit board that is paused at the back detection position.

Images