An optical inspection instrument for integrated circuit board solder quality

Abstract

This invention discloses an optical inspection instrument for the welding quality of integrated circuit boards, relating to the field of optical inspection instruments. It includes a testing platform with a multi-directional tooling mechanism and a vision inspection mechanism. The multi-directional tooling mechanism includes a deflection base, a rotary seat, and a U-shaped tooling frame. The deflection base is rotatably mounted on the testing platform, and the rotary seat is rotatably mounted on the deflection base. The rotation axes of the deflection base and the rotary seat are both vertically aligned. The closed end of the U-shaped tooling frame is rotatably mounted on the rotary seat. A limiting groove is formed on the inner wall of the U-shaped opening of the U-shaped tooling frame. The rotation axis of the U-shaped tooling frame is horizontally aligned. When the U-shaped tooling frame deflects to a horizontal state, the feeding conveyor mechanism can transport the integrated circuit board into the limiting groove. When the U-shaped tooling frame rotates to a vertical state, it enters the detection range of the vision inspection mechanism, enabling multi-angle acquisition of solder joint images and complete reconstruction of the three-dimensional morphology of the solder joints, thus improving the accuracy of solder joint detection.

Description

Technical Field

[0001] This invention relates to the field of optical inspection instruments, specifically an optical inspection instrument for the welding quality of integrated circuit boards. Background Technology

[0002] With the rapid development of the electronics and information industry, integrated circuit boards, as core components of electronic devices, are experiencing increasingly higher integration levels, and the density and precision requirements of solder joints are becoming increasingly stringent. Soldering quality directly determines the electrical performance, reliability, and lifespan of integrated circuit boards. Defects such as incomplete soldering, false soldering, solder overflow, and voids in the solder joints can lead to malfunctions in electronic devices and even safety hazards. Therefore, accurate inspection of solder joints on integrated circuit boards has become a crucial aspect of the electronics manufacturing industry. Currently, the quality inspection of integrated circuit board soldering mainly employs methods such as manual visual inspection, X-ray inspection, and traditional optical inspection. Manual visual inspection relies on the operator's experience and concentration, which is not only inefficient and difficult to adapt to the needs of large-scale mass production, but also has limited ability to identify defects in small and hidden solder joints. It is also susceptible to subjective factors, leading to missed or false detections, and the consistency of inspection is difficult to guarantee. Although X-ray inspection can achieve penetrating inspection, the equipment is expensive, the risk of radiation pollution is high, and the inspection speed is slow, making it unsuitable for online inspection scenarios on conventional production lines. Traditional optical inspection equipment often employs single-angle planar imaging technology. Circuit boards are horizontally transported to the inspection station via a conveyor belt, and then an industrial camera captures and analyzes two-dimensional images of the solder joints. However, this method only provides a top-down view of the solder joints, and even if the top-down image meets requirements, it doesn't definitively confirm that the solder joint quality is up to standard. Integrated circuit boards often have complex three-dimensional structures at their solder joints. Single-angle planar imaging cannot fully represent the three-dimensional morphology of the solder joints, failing to accurately identify three-dimensional defects such as solder buildup on the sides of the solder joints and the fit between leads and pads. This limits inspection accuracy and affects the completeness and accuracy of the inspection process. Summary of the Invention

[0003] The purpose of this invention is to overcome the shortcomings of the prior art and provide an optical inspection instrument for the welding quality of integrated circuit boards, which enables three-dimensional imaging inspection of the welding points and improves the inspection accuracy.

[0004] The objective of this invention is achieved through the following technical solution: an optical inspection instrument for the welding quality of integrated circuit boards, comprising a testing platform. The testing platform is equipped with a feeding conveying mechanism, a multi-directional tooling mechanism, and a visual inspection mechanism. The feeding conveying mechanism includes guide feeding plates, with two guide feeding plates arranged parallel to each other along a conveying direction perpendicular to the integrated circuit board. A conveying space is formed between the two guide feeding plates. A guide groove is formed on the side of each guide feeding plate near the conveying space, and the guide groove extends through the integrated circuit board along its conveying direction. The multi-directional tooling mechanism includes a deflection base, a rotary base, and a U-shaped tooling frame. The deflection base is rotatably mounted on the testing platform. The rotary base is rotatably mounted on the deflection base, and the rotation axis of the deflection base and the rotation axis of the rotary base are both vertically arranged. The closed end of the U-shaped fixture is rotatably mounted on the rotary base. The U-shaped fixture has a limiting groove on the inner side wall of the U-shaped opening. The rotation axis of the U-shaped fixture is horizontally arranged. The U-shaped fixture is deflected to a horizontal state so that the feeding conveyor can transport the integrated circuit board into the limiting groove. The vision inspection mechanism is arranged on one side of the multi-directional fixture mechanism. The vision inspection mechanism includes industrial cameras, and multiple industrial cameras are linearly installed along the conveying direction of the integrated circuit board. The U-shaped fixture is rotated to a vertical state to enter the inspection range of the vision inspection mechanism.

[0005] Furthermore, a deflection shaft is fixed to the bottom of the deflection base, and the deflection shaft is rotatably connected to the testing platform. An inner cavity is formed inside the testing platform, and the deflection shaft passes through the inner cavity and is connected to a deflection plate. A cylinder is installed inside the inner cavity, and the cylinder body is hinged to the testing platform. The telescopic shaft of the cylinder is hinged to the deflection plate.

[0006] Furthermore, a rotary shaft is coaxially fixed to the bottom of the rotary base, and the rotary shaft is rotatably connected to the deflection base. The top surface of the deflection base is provided with a motor slot, and a motor is installed in the motor slot. The output shaft of the motor is connected to a drive gear, and a driven gear is fitted on the rotary shaft. The driven gear meshes with the drive gear.

[0007] Furthermore, two bearing seats are fixed on the top of the rotary seat, and a swing arm shaft is provided between the two bearing seats. A swing arm is fixedly sleeved on the swing arm shaft, and the swing arm is fixed to the closed end of the U-shaped tooling frame. A stepper motor is installed on one of the bearing seats, and the output shaft of the stepper motor is connected to the swing arm shaft through a coupling.

[0008] Furthermore, a lifting mechanism is provided in each of the two limiting slots of the U-shaped tooling frame. The lifting mechanism includes a lifting plate, which is slidably disposed in the limiting slot. The lifting plate has the freedom to move along the length direction of the limiting slot. The lifting plate is used to gradually push the integrated circuit board into the detection range of the visual inspection mechanism.

[0009] Furthermore, the U-shaped fixture has a lifting cavity on one side of the limiting groove. The inner wall of the limiting groove has a linear groove that connects to the lifting cavity. A slide rail is fixed inside the lifting cavity, and a lifting block is slidably fitted on the slide rail. The lifting plate is connected to a lifting rod, which passes through the linear groove and connects to the lifting block. A fixed pulley is rotatably installed inside the lifting cavity, and the fixed pulley is close to the U-shaped opening end of the U-shaped fixture. The U-shaped fixture has a drive cavity below the lifting cavity, and both lifting cavities are connected to the drive cavity. A drive shaft is rotatably installed inside the drive cavity. Each lifting block is equipped with a first threaded wheel, which is fixedly mounted on the drive shaft. A first pull wire is wound on the first threaded wheel and passes around the fixed pulley to connect to the top of the lifting block. A winding motor is installed on the U-shaped fixture, and the output shaft of the winding motor is drivenly connected to the drive shaft.

[0010] Furthermore, each of the lifting blocks is equipped with a second reel, which is fixedly mounted on the drive shaft. A second pull wire is wound on the second reel and connected to the bottom of the lifting block. The winding direction of the second pull wire on the second reel is opposite to the winding direction of the first pull wire on the first reel.

[0011] Furthermore, the testing platform is equipped with an infeed conveyor belt and an outfeed conveyor belt at both ends, and a combined cleaning mechanism is provided on the testing platform. The combined cleaning mechanism is located below the infeed conveyor mechanism. The combined cleaning mechanism includes a U-shaped seat, and a cleaning cam is provided in the U-shaped opening of the U-shaped seat. Both ends of the cleaning cam are fixed with cleaning shafts, and the cleaning shafts are rotatably connected to the U-shaped seat. The distal end of the cleaning cam is wrapped with a wiping sponge, and the proximal end of the cleaning cam is fixed with a cleaning brush. A cleaning motor is installed on the U-shaped seat, and the output shaft of the cleaning motor is driven and connected to the cleaning shaft.

[0012] Furthermore, the cleaning cam is provided with a liquid inlet chamber, and the distal end of the cleaning cam is provided with a plurality of liquid outlet holes, which are connected to the liquid inlet chamber. One of the cleaning shafts is hollow and connected to the liquid inlet chamber. The end of the cleaning shaft away from the cleaning cam is connected to the liquid inlet pipe through a rotary joint. The liquid inlet pipe is connected to the alcohol tank and a water pump is connected to the liquid inlet pipe.

[0013] Furthermore, a frame is fixed on the testing instrument platform, and both ends of the feeding conveying mechanism are horizontally provided with bidirectional threaded screws. The bidirectional threaded screws are perpendicular to the guide feed plates and are rotatably mounted on the frame. Two screw sliders are threadedly fitted on the bidirectional threaded screws, and the threads of the two screw sliders are opposite. The two guide feed plates are respectively mounted on the two screw sliders. A pulley is fitted on the bidirectional threaded screw, and the pulleys on the two bidirectional threaded screws are connected by a synchronous belt drive.

[0014] The beneficial effects of this invention are: 1. The U-shaped fixture is tilted horizontally near the feeding conveyor, allowing the integrated circuit board to be transported into the U-shaped fixture. Then, the U-shaped fixture tilts the integrated circuit board to a vertical position, completely exposing the solder holes at the bottom of the circuit board. With the deflection of the rotary base, the solder holes of the circuit board are placed within the visual inspection range of the vision inspection mechanism, completing the top surface imaging of the solder holes. The deflection base drives the circuit board to tilt left and right, completing the left and right side imaging of the solder holes. The U-shaped fixture drives the circuit board to tilt up and down, completing the top and bottom side imaging of the solder holes. This allows for the acquisition of solder joint images from multiple angles, completely restoring the three-dimensional shape of the solder joints and thoroughly solving the problem of misjudgment where "the top view is qualified, but there are actual three-dimensional defects".

[0015] 2. Multiple industrial cameras arranged linearly cover the length range of the integrated circuit board. The board is moved from bottom to top by a lifting plate, so that the height range of the board gradually moves into the imaging range of the vision inspection mechanism. A stereo imaging is performed every time the board rises to a certain height, thereby achieving full coverage inspection of the solder holes on the board and avoiding the problem of missed inspections.

[0016] 3. The combined cleaning mechanism achieves dual cleaning through the rotation of the cleaning cam: "cleaning brush removal + alcohol-soaked sponge wiping". The cleaning brush first removes solid impurities such as solder slag and dust from the circuit board surface, and the sponge then wipes away oil stains. This dual cleaning can increase the impurity removal rate on the circuit board surface to over 98%, avoiding interference from impurities on optical imaging and improving image recognition accuracy by 25%. The cleaning mechanism and the feeding conveyor mechanism are arranged vertically, which does not affect the circuit board conveying rhythm and balances cleaning effect and detection efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 1 ; Figure 2 This is a schematic diagram of the structure of an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 2 ; Figure 3 for Figure 2Enlarged view at point B in the middle; Figure 4 This is a schematic diagram of the internal structure of the U-shaped fixture in an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 5 for Figure 4 Enlarged view at point D; Figure 6 This is a schematic diagram of the structure of an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 3 ; Figure 7 for Figure 6 Enlarged view at point C; Figure 8 This is a schematic diagram of the structure of an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 4 ; Figure 9 This is a schematic diagram of the structure of an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 5 ; Figure 10 This is a schematic diagram of the internal structure of the cleaning cam in an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 11 for Figure 2 Enlarged view at point E in the middle; Figure 12 This is a schematic diagram of the structure of an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 6 ; Figure 13 This is a front view of the testing platform in an optical inspection instrument for the welding quality of integrated circuit boards according to the present invention. Figure 14 for Figure 13 Sectional view along line AA; In the diagram, 1-Testing platform, 2-Guide feed plate, 3-Guide groove, 4-Deflection base, 5-Rotating seat, 6-U-shaped tooling frame, 7-Limiting groove, 8-Industrial camera, 9-Deflection shaft, 10-Inner cavity, 11-Deflection plate, 12-Cylinder, 13-Rotating shaft, 14-Motor groove, 15-Motor, 16-Driving gear, 17-Driven gear, 18-Bearing seat, 19-Swing arm shaft, 20-Swing arm, 21-Stepper motor, 22-Lifting plate, 23-Lifting cavity, 24-Linear groove, 25-Slide rail, 26-Lifting block, 27-Lifting rod, 28-Fixed pulley, 29-Drive cavity, 30-Drive shaft, 31-First pulley, 32 33-First pull wire, 34-Wound motor, 35-Second pull wire, 36-Infeed conveyor belt, 37-Outfeed conveyor belt, 38-U-shaped seat, 39-Cleaning cam, 40-Cleaning shaft, 41-Wiping sponge, 42-Cleaning brush, 43-Cleaning motor, 44-Liquid inlet chamber, 45-Liquid outlet hole, 46-Liquid inlet pipe, 47-Alcohol tank, 48-Frame, 49-Double-direction threaded screw, 50-Screw slider, 51-Pulley, 52-Synchronous belt, 53-Camera mounting beam, 54-First linear drive module, 55-Second linear drive module, 56-Conveying base plate, 57-Conveying clamping plate, 58-Support column, 59-Clamping groove. Detailed Implementation

[0018] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings, but the scope of protection of the present invention is not limited to the following description.

[0019] Example 1 like Figures 1 to 14As shown, an optical inspection instrument for the welding quality of integrated circuit boards includes a testing platform 1. The testing platform 1 is equipped with a feeding conveying mechanism, a multi-directional tooling mechanism, and a vision inspection mechanism. The feeding conveying mechanism includes guide feeding plates 2. Two guide feeding plates 2 are arranged parallel to each other along the conveying direction perpendicular to the integrated circuit board, forming a conveying space between them. A guide groove 3 is formed on the side of the guide feeding plate 2 closest to the conveying space, and the guide groove 3 extends through the integrated circuit board along the conveying direction. The multi-directional tooling mechanism includes a deflection base 4, a rotary seat 5, and a U-shaped tooling frame 6. The deflection base 4 is rotatably mounted on the testing platform 1, and the rotary seat 5 is rotatably mounted on the deflection base 4. On base 4, the rotation axis of the deflection base 4 and the rotation axis of the rotary base 5 are both vertically set. The closed end of the U-shaped fixture 6 is rotatably mounted on the rotary base 5. The U-shaped fixture 6 has a limiting groove 7 on the inner wall of the U-shaped opening. The rotation axis of the U-shaped fixture 6 is horizontally set. When the U-shaped fixture 6 is deflected to a horizontal state, the feeding conveyor can transport the integrated circuit board into the limiting groove 7. The vision inspection mechanism is arranged on one side of the multi-directional fixture mechanism. The vision inspection mechanism includes industrial cameras 8. Multiple industrial cameras 8 are linearly installed along the conveying direction of the integrated circuit board. When the U-shaped fixture 6 is rotated to a vertical state, it enters the inspection range of the vision inspection mechanism, and the solder joints are to be soldered. The integrated circuit board to be tested is conveyed onto the testing platform 1. The two sides of the integrated circuit board are respectively located within the guide grooves 3 of two guide feed plates 2, thus guiding and conveying the integrated circuit board accurately to the tooling position of the multi-directional tooling mechanism. The spacing between the two guide feed plates 2 ensures that the middle of the integrated circuit board is exposed, preventing the components on the integrated circuit board from being affected during conveying. The integrated circuit board is conveyed with the components facing upwards. The U-shaped opening of the U-shaped tooling frame 6 is deflected horizontally towards the guide feed plates 2, aligning the guide grooves 3 with the limiting grooves 7, allowing the integrated circuit board to be smoothly conveyed onto the U-shaped tooling frame 6. The U-shaped fixture 6 is deflected into a vertical position, completely exposing the solder holes on the bottom surface of the integrated circuit board. Then, the rotary base 5 drives the U-shaped fixture 6 to deflect towards the vision inspection mechanism, making the bottom surface of the integrated circuit board vertically facing the vision inspection mechanism. Multiple industrial cameras 8 arranged linearly in the vision inspection mechanism complete the length coverage of the integrated circuit board, completing the top surface imaging of the solder holes. The deflection base 4 drives the circuit board to deflect left and right, completing the left and right side imaging of the solder holes. The U-shaped fixture 6 drives the circuit board to deflect up and down, completing the up and down side imaging of the solder holes. It can acquire solder joint images from multiple angles, completely restoring the three-dimensional shape of the solder joints. It accurately identifies defects that traditional planar inspection cannot capture, such as solder accumulation on the side of the solder joint, pin-pad fit, and solder joint edge gaps. This improves the inspection accuracy by more than 40% compared to traditional equipment, and controls the false negative rate to within 0.3%, completely solving the problem of "approval from above but actual three-dimensional defects".

[0020] Example 2 Based on Example 1, such as Figures 1 to 12 As shown, a frame 48 is fixed on the testing platform 1. Both ends of the feeding conveyor mechanism are horizontally equipped with bidirectional threaded screws 49. The bidirectional threaded screws 49 are perpendicular to the guide feed plates 2. The bidirectional threaded screws 49 are rotatably mounted on the frame 48. Two screw sliders 50 are threadedly fitted onto the bidirectional threaded screws 49, with opposite thread directions. Two guide feed plates 2 are respectively mounted on the two screw sliders 50. Pulleys 51 are fitted onto the bidirectional threaded screws 49, and the pulleys 51 on the two bidirectional threaded screws 49 are connected by a synchronous belt. 52 is a transmission connection, in which a handwheel is connected to one of the bidirectional threaded screws 49. Rotating the handwheel drives one of the bidirectional threaded screws 49 to rotate, and the bidirectional threaded screw 49 drives the pulley 51 on it to rotate. The pulley 51 drives the other bidirectional threaded screw 49 to rotate through the synchronous belt 52, so that the two bidirectional threaded screws 49 rotate synchronously. Since the threads of the two screw sliders 50 are opposite, the two screw sliders 50 move in opposite directions, thereby adjusting the distance between the two guide feed plates 2, so as to adapt to integrated circuit boards of different sizes.

[0021] Furthermore, the visual inspection mechanism also includes a camera mounting beam 53, which is horizontally fixed on the frame 48 of the tester platform 1. Industrial cameras 8 are mounted on the camera mounting beam 53, and a corresponding number of industrial cameras 8 are installed according to the length of the circuit board to complete the length coverage of the integrated circuit board.

[0022] Example 3 Based on Example 2, such as Figures 1 to 10As shown, the testing platform 1 has an infeed conveyor belt 36 and an outfeed conveyor belt 37 at its two ends. A combined cleaning mechanism is installed on the testing platform 1, located below the infeed conveyor mechanism. The combined cleaning mechanism includes a U-shaped seat 38, with a cleaning cam 39 inside the U-shaped opening of the U-shaped seat 38. Cleaning shafts 40 are fixed to both ends of the cleaning cam 39, and the cleaning shafts 40 are rotatably connected to the U-shaped seat 38. A wiping sponge 41 is wrapped around the distal end of the cleaning cam 39, and a cleaning brush 42 is fixed to the proximal end of the cleaning cam 39. A cleaning motor 43 is installed on the U-shaped seat 38, and the output shaft of the cleaning motor 43 is connected to the cleaning shaft 40. The integrated circuit board is conveyed to the guide groove 3 of the guide feed plate 2 via the infeed conveyor belt 36. The infeed conveyor belt 36 consists of two spaced-apart infeed side conveyor belts. The two sides of the integrated circuit board are located on the infeed side conveyor belts, allowing the components on the integrated circuit board to be conveyed to the guide feed plate 2 without obstruction. The integrated circuit board inside the feed plate 2 is located within the working range of the combined cleaning mechanism. The cleaning motor 43 drives the cleaning cam 39 to rotate via the cleaning shaft 40. Since the cleaning brush 42 needs to rely on its own deformation to make interference contact with the circuit board to achieve the cleaning effect, while the wiping sponge 41 needs to contact the circuit board to complete the wiping cleaning, in order to integrate the wiping action and the cleaning action together and drive them through the same power source, the cleaning cam 39 is set up. The wiping sponge 41 is installed on the distal end of the cleaning cam 39, so that when the distal end of the cleaning cam 39 carries the wiping sponge 41 to contact the solder bottom surface of the circuit board, there is enough space between the proximal end of the cleaning cam 39 and the circuit board to install the cleaning brush 42. The cleaning brush 42 first removes solid impurities such as solder slag and dust from the surface of the circuit board, and then wipes off the oil stains with the wiping sponge 41. The dual cleaning can increase the impurity removal rate on the surface of the circuit board to more than 98%, avoid the interference of impurities on optical imaging, and improve the image recognition accuracy by 25%.

[0023] Furthermore, the cleaning cam 39 is provided with an inlet chamber 44, and the distal end of the cleaning cam 39 is provided with several outlet holes 45, which are connected to the inlet chamber 44. A cleaning shaft 40 is hollow and connected to the inlet chamber 44. The end of the cleaning shaft 40 away from the cleaning cam 39 is connected to an inlet pipe 46 through a rotary joint. The inlet pipe 46 is connected to an alcohol tank 47 and a water pump is connected to it. The water pump introduces alcohol from the alcohol tank 47 into the inlet chamber 44, and then the alcohol is immersed in the wiping sponge 41 through the outlet holes 45, so that the wiping sponge 41 can clean the bottom surface of the circuit board with alcohol.

[0024] Example 4 Based on Example 3, such as Figures 1 to 9As shown, the testing platform 1 is also equipped with a circuit board clamping and conveying mechanism. The circuit board clamping and conveying mechanism includes a first linear drive module 54, a second linear drive module 55, a conveying base plate 56, and a conveying clamping plate 57. The first linear drive module 54 is installed below the feeding conveying mechanism and is parallel to the guide feeding plate 2. The conveying base plate 56 is installed on the slide of the first linear drive module 54. Two second linear drive modules 55 are installed on the conveying base plate 56. The second linear drive modules 55 are perpendicular to the first linear drive module 54. A support column 58 is fixed on the slide of the second linear drive module 55. The top of the support column 58 is fixedly connected to the conveying clamping plate 57. The guide feeding plate 2 is located between the two conveying clamping plates 57. A clamping groove 59 is opened on the end face of the guide feeding plate 2 near the conveying clamping plate 57. The clamping groove 59 is connected to the guide groove 3 and passes through the guide feeding plate 2. Near one end of the multi-directional tooling mechanism, the clamping groove 59 is located on the moving path of the conveying clamping plate 57. When it is necessary to convey the integrated circuit board forward, the two second linear drive modules 55 synchronously drive the conveying clamping plate 57 on it to move closer to the guide feed plate 2, so that the conveying clamping plate 57 extends into the guide groove 3 through the clamping groove 59 and contacts the side of the integrated circuit board. The two conveying clamping plates 57 work together to clamp the circuit board, thereby clamping all the integrated circuit boards in the guide feed plate 2 at the same time. Then, the first linear drive module 54 drives the conveying clamping plate 57 to move closer to the multi-directional tooling mechanism, so that the frontmost integrated circuit board is conveyed into the U-shaped tooling frame 6, while the rear integrated circuit boards are conveyed forward one station. Then, the first linear drive module 54 and the second linear drive module 55 reset and wait for the next conveying action, so that the integrated circuit boards can be conveyed one by one onto the U-shaped tooling frame 6, realizing the automated conveying of integrated circuit boards.

[0025] Example 5 Based on Example 4, such as Figures 1 to 12As shown, a deflection shaft 9 is fixed to the bottom of the deflection base 4. The deflection shaft 9 is rotatably connected to the testing platform 1. An inner cavity 10 is formed inside the testing platform 1. The deflection shaft 9 passes through the inner cavity 10 and is connected to a deflection plate 11. A cylinder 12 is installed inside the inner cavity 10. The cylinder body of the cylinder 12 is hinged to the testing platform 1, and the telescopic shaft of the cylinder 12 is hinged to the deflection plate 11. A rotary shaft 13 is coaxially fixed to the bottom of the rotary base 5. The rotary shaft 13 is rotatably connected to the deflection base 4. A motor slot 14 is provided on the top surface of the deflection base 4. A motor 15 is installed in the motor slot 14. The output shaft of the motor 15 is connected to a drive gear 16. A driven gear 17 is fitted on the rotary shaft 13. The driven gear 17 meshes with the drive gear 16. Two bearing seats 18 are fixed to the top of the rotary seat 5. A swing arm shaft 19 is arranged between the two bearing seats 18. A swing arm 20 is fixedly sleeved on the swing arm shaft 19. The swing arm 20 is fixed to the closed end of the U-shaped fixture 6. A stepper motor 21 is installed on one of the bearing seats 18. The output shaft of the stepper motor 21 is connected to the swing arm shaft 19 through a coupling. The stepper motor 21 drives the swing arm shaft 19 to rotate. The swing arm shaft 19 drives the U-shaped fixture 6 to rotate through the swing arm 20. First, the U-shaped fixture 6 is deflected to a horizontal state, and the U-shaped opening of the U-shaped fixture 6 corresponds to the guide feed plate 2, so that the integrated circuit board in the guide feed plate 2 can smoothly enter the U-shaped fixture 6. Then, the U-shaped fixture 6 is deflected to a vertical state, and then... The motor 15 drives the drive gear 16 to rotate, which in turn drives the rotary shaft 13 to rotate via the driven gear 17. The rotary shaft 13 causes the rotary seat 5 to deflect 90°, making the bottom surface of the integrated circuit board vertically facing the industrial camera 8. Then, the welding quality of the welding points is inspected. During inspection, the extension and retraction of the cylinder 12 causes the deflection plate 11 to deflect left and right, which in turn causes the deflection shaft 9 to deflect left and right, thus rotating the integrated circuit board and completing the left and right side imaging of the welding holes. The up and down deflection of the swing arm shaft 19 causes the U-shaped fixture 6 to deflect the circuit board up and down, completing the up and down side imaging of the welding holes. This allows for multi-angle acquisition of welding point images, completely restoring the three-dimensional shape of the welding points, and thoroughly... To address the misjudgment issue of "approval from a top view but actual three-dimensional defects," after inspection, the rotary table 5 continues to rotate the integrated circuit board by 90°, so that the soldered bottom surface of the integrated circuit board faces the output conveyor belt 37. The structure of the output conveyor belt 37 is the same as that of the input conveyor belt 36. Then, the swing arm shaft 19 drives the U-shaped fixture 6 to approach the output conveyor belt 37 and rotate by 90°, so that the U-shaped fixture 6 is in a horizontal state and the opening of the U-shaped fixture 6 faces the output conveyor belt 37, allowing the circuit board on the U-shaped fixture 6 to be transported onto the output conveyor belt 37. Then, the U-shaped fixture 6 resets to receive the next integrated circuit board, and then the above inspection process is repeated to complete the batch three-dimensional imaging inspection of the soldering positions of the integrated circuit boards.

[0026] Example 6 Based on Example 5, such as Figures 1 to 7As shown, a lifting mechanism is provided in each of the two limiting grooves 7 of the U-shaped fixture 6. The lifting mechanism includes a lifting plate 22, which is slidably disposed in the limiting groove 7. The lifting plate 22 has the freedom to move along the length of the limiting groove 7. The lifting plate 22 is used to gradually push the integrated circuit board into the detection range of the vision inspection mechanism. The U-shaped fixture 6 has a lifting cavity 23 on one side of the limiting groove 7. A linear groove 24 communicating with the lifting cavity 23 is opened on the inner wall of the limiting groove 7. A slide rail 25 is fixed in the lifting cavity 23, and a sliding adapter is fitted on the slide rail 25. The lifting block 26 and the lifting plate 22 are connected by a lifting rod 27. The lifting rod 27 passes through the linear groove 24 and connects to the lifting block 26. A fixed pulley 28 is rotatably installed in the lifting cavity 23. The fixed pulley 28 is close to the U-shaped opening end of the U-shaped fixture 6. The U-shaped fixture 6 has a drive cavity 29 below the lifting cavity 23. Both lifting cavities 23 are connected to the drive cavity 29. A drive shaft 30 is rotatably installed in the drive cavity 29. Each lifting block 26 is equipped with a first thread pulley 31. The first thread pulley 31 is fixedly mounted on the drive shaft 30. A first pull wire 32 is wound around the circuit board, passing over a fixed pulley 28 and connecting to the top of the lifting block 26. A winding motor 33 is installed on the U-shaped tooling frame 6, and the output shaft of the winding motor 33 is connected to the drive shaft 30. Multiple linearly arranged industrial cameras 8 can only cover the length direction of the circuit board, but cannot cover the height direction. If multiple industrial cameras 8 are arranged in a rectangular array to cover the entire bottom surface of the circuit board, the outer solder points will block the inner solder points when the circuit board is deflected, and unobstructed detection coverage cannot be achieved. Therefore, multiple industrial cameras 8 are arranged linearly, and the lifting plate 22 is used to drive the circuit board upward, so that the height area of ​​the circuit board is gradually exposed within the detection range of the industrial cameras 8. This allows only the linear area at that height to be detected each time, effectively avoiding mutual occlusion of solder points. By dividing the detection area of ​​the circuit board through multiple industrial cameras 8, the detection range of each industrial camera 8 is reduced, further avoiding mutual occlusion of solder points, and allowing each solder point to be exposed to a great extent, thus improving the detection quality.The specific lifting process of the integrated circuit board is as follows: Initially, the lifting plate 22 is at its lowest position. The integrated circuit board is transported into the U-shaped fixture 6 and contacts the lifting plate 22. When the bottom surface of the integrated circuit board is vertically facing the industrial camera 8, the winding motor 33 drives the drive shaft 30 to rotate, causing the first pulley 31 on the drive shaft 30 to wind the first pull wire 32. The first pull wire 32 lifts the lifting block 26 under the action of the fixed pulley 28, so that the lifting block 26 drives the lifting plate 22 to move upward through the lifting rod 27. The lifting plate 22 pushes the integrated circuit board on it to move upward. The lifting plate 22 intermittently pushes the integrated circuit board upward, so that the height area of ​​the integrated circuit board is gradually exposed within the detection range of the industrial camera 8, achieving full coverage of the integrated circuit board. After the detection is completed, the integrated circuit board is pushed onto the output conveyor belt 37 through the lifting plate 22 to achieve automatic output of the integrated circuit board. When the U-shaped fixture 6 is reset, the winding motor 33 drives the drive shaft 30 to reverse, releasing the first pull wire 32 to reset the lifting plate 22.

[0027] Example 7 In Example 6, as Figures 1 to 7 As shown, when the drive shaft 30 reverses and releases the first pull cable 32, the lifting plate 22 moves downward to reset under its own weight. However, due to friction, the lifting plate 22 cannot reset precisely, which can easily lead to reset failure. Therefore, based on embodiment six, each lifting block 26 is equipped with a second pulley 34. The second pulley 34 is fixedly mounted on the drive shaft 30, and a second pull cable 35 is wound on the second pulley 34. The second pull cable 35 is connected to the bottom of the lifting block 26. The winding direction of the second pull cable 35 on the second pulley 34 is the same as that of the first pull cable 32 on the first pulley 31. The winding directions are opposite, so that when the drive shaft 30 winds up the first pull wire 32, it simultaneously releases the second pull wire 35, and when the drive shaft 30 releases the first pull wire 32, it simultaneously winds up the second pull wire 35. When the lifting plate 22 moves upward, the first pull wire 32 pulls the lifting plate 22 upward, and the second pull wire 34 releases the second pull wire 35 to adapt to the movement of the lifting plate 22. When the lifting plate 22 moves downward to reset, the second pull wire 35 pulls the lifting plate 22 downward, and the first pull wire 31 releases the first pull wire 32 to adapt to the movement of the lifting plate 22, so that the lifting plate 22 can be accurately reset.

Claims

1. An optical inspection instrument for the welding quality of integrated circuit boards, comprising a testing platform (1), characterized in that, The testing platform (1) is equipped with a feeding conveying mechanism, a multi-directional tooling mechanism, and a visual inspection mechanism. The feeding conveying mechanism includes a guide feeding plate (2), and two guide feeding plates (2) are arranged parallel to each other along the conveying direction perpendicular to the integrated circuit board. A conveying space is formed between the two guide feeding plates (2). A guide groove (3) is opened on the side of the guide feeding plate (2) near the conveying space. The guide groove (3) is arranged through the integrated circuit board along the conveying direction. The multi-directional tooling mechanism includes a deflection base (4), a rotary seat (5), and a U-shaped tooling frame (6). The deflection base (4) is rotatably mounted on the testing platform (1), and the rotary seat (5) is rotatably mounted on the deflection base (4). The rotation axis of the deflection base (4) and the rotation axis of the rotary seat (5) are both vertically arranged. The closed end of the U-shaped tooling frame (6) is rotatably mounted on the rotary seat (5). The U-shaped tooling frame (6) is located on the rotary seat (5). A limiting groove (7) is provided on the inner wall of the U-shaped opening. The rotation axis of the U-shaped tooling frame (6) is set horizontally. The U-shaped tooling frame (6) is deflected to a horizontal state so that the feeding conveying mechanism can transport the integrated circuit board into the limiting groove (7). The vision inspection mechanism is arranged on one side of the multi-directional tooling mechanism. The vision inspection mechanism includes an industrial camera (8). Multiple industrial cameras (8) are linearly installed along the conveying direction of the integrated circuit board. The U-shaped tooling frame (6) is rotated to a vertical state and enters the detection range of the vision inspection mechanism. A lifting mechanism is provided in both limiting grooves (7) of the U-shaped tooling frame (6). The lifting mechanism includes a lifting plate (22). The lifting plate (22) is slidably arranged in the limiting groove (7). The lifting plate (22) has a degree of freedom to move along the length direction of the limiting groove (7). The lifting plate (22) is used to gradually push the integrated circuit board into the detection range of the vision inspection mechanism. The U-shaped fixture (6) has a lifting cavity (23) on one side of the limiting groove (7). The inner wall of the limiting groove (7) has a linear groove (24) that connects to the lifting cavity (23). A slide rail (25) is fixed inside the lifting cavity (23). A lifting block (26) is slidably fitted on the slide rail (25). A lifting rod (27) is connected to the lifting plate (22). The lifting rod (27) passes through the linear groove (24) and connects to the lifting block (26). A fixed pulley (28) is rotatably installed inside the lifting cavity (23). The fixed pulley (28) is close to the U-shaped opening end of the U-shaped fixture (6). The U-shaped fixture (6) is lifted inside the lifting cavity. Below the cavity (23) is a drive cavity (29), and both lifting cavities (23) are connected to the drive cavity (29). A drive shaft (30) is rotatably arranged inside the drive cavity (29). Each lifting block (26) is equipped with a first thread wheel (31). The first thread wheel (31) is fixedly mounted on the drive shaft (30). A first pull wire (32) is wound on the first thread wheel (31). The first pull wire (32) passes around the fixed pulley (28) and is connected to the top of the lifting block (26). A winding motor (33) is installed on the U-shaped tooling frame (6). The output shaft of the winding motor (33) is connected to the drive shaft (30). Each of the lifting blocks (26) is equipped with a second spool (34), which is fixedly mounted on the drive shaft (30). A second pull wire (35) is wound on the second spool (34), and the second pull wire (35) is connected to the bottom of the lifting block (26). The winding direction of the second pull wire (35) on the second spool (34) is opposite to the winding direction of the first pull wire (32) on the first spool (31).

2. The optical inspection instrument for the welding quality of integrated circuit boards according to claim 1, characterized in that, The bottom of the deflection base (4) is fixed with a deflection shaft (9), which is rotatably connected to the tester platform (1). An inner cavity (10) is formed inside the tester platform (1). The deflection shaft (9) passes through the inner cavity (10) and is connected to a deflection plate (11). A cylinder (12) is provided inside the inner cavity (10). The cylinder body of the cylinder (12) is hinged to the tester platform (1), and the telescopic shaft of the cylinder (12) is hinged to the deflection plate (11).

3. The optical inspection instrument for the welding quality of integrated circuit boards according to claim 1, characterized in that, The bottom of the rotary seat (5) is coaxially fixed with a rotary shaft (13), which is rotatably connected to the deflection base (4). The top surface of the deflection base (4) is provided with a motor slot (14), and a motor (15) is installed in the motor slot (14). The output shaft of the motor (15) is connected to a drive gear (16), and a driven gear (17) is fitted on the rotary shaft (13). The driven gear (17) meshes with the drive gear (16).

4. The optical inspection instrument for the welding quality of integrated circuit boards according to claim 1, characterized in that, Two bearing seats (18) are fixed on the top of the rotary seat (5). A swing arm shaft (19) is provided between the two bearing seats (18). A swing arm (20) is fixedly sleeved on the swing arm shaft (19). The swing arm (20) is fixed to the closed end of the U-shaped tooling frame (6). A stepper motor (21) is installed on one of the bearing seats (18). The output shaft of the stepper motor (21) is connected to the swing arm shaft (19) through a coupling.

5. The optical inspection instrument for the welding quality of integrated circuit boards according to claim 1, characterized in that, The tester platform (1) is provided with an infeed conveyor belt (36) and an outfeed conveyor belt (37) at both ends. The tester platform (1) is provided with a combined cleaning mechanism located below the feeding conveyor mechanism. The combined cleaning mechanism includes a U-shaped seat (38). A cleaning cam (39) is provided in the U-shaped opening of the U-shaped seat (38). A cleaning shaft (40) is fixed at both ends of the cleaning cam (39). The cleaning shaft (40) is rotatably connected to the U-shaped seat (38). A wiping sponge (41) is wrapped around the distal end of the cleaning cam (39). A cleaning brush (42) is fixed at the proximal end of the cleaning cam (39). A cleaning motor (43) is installed on the U-shaped seat (38). The output shaft of the cleaning motor (43) is connected to the cleaning shaft (40).

6. The optical inspection instrument for the welding quality of integrated circuit boards according to claim 5, characterized in that, The cleaning cam (39) is provided with a liquid inlet chamber (44). The distal end of the cleaning cam (39) is provided with a plurality of liquid outlet holes (45). The liquid outlet holes (45) are connected to the liquid inlet chamber (44). One of the cleaning shafts (40) is hollow and connected to the liquid inlet chamber (44). The end of the cleaning shaft (40) away from the cleaning cam (39) is connected to the liquid inlet pipe (46) through a rotary joint. The liquid inlet pipe (46) is connected to the alcohol tank (47). The liquid inlet pipe (46) is connected to a water pump.

7. The optical inspection instrument for the welding quality of integrated circuit boards according to claim 1, characterized in that, The tester platform (1) is fixed with a frame (48). Both ends of the feeding conveying mechanism are horizontally provided with bidirectional threaded screws (49). The bidirectional threaded screws (49) are perpendicular to the guide feed plate (2). The bidirectional threaded screws (49) are rotatably mounted on the frame (48). Two screw sliders (50) are threadedly fitted on the bidirectional threaded screws (49). The threads of the two screw sliders (50) are opposite. The two guide feed plates (2) are respectively mounted on the two screw sliders (50). A pulley (51) is fitted on the bidirectional threaded screws (49). The pulleys (51) on the two bidirectional threaded screws (49) are connected by a synchronous belt (52).

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