An automatic sorting device for visual inspection of surface defects in LED screens

Abstract

This invention belongs to the field of sorting devices, specifically an automatic sorting device for visual inspection of surface defects in LED screens. It includes a first conveyor, a second conveyor, and a visual inspection mechanism. The second conveyor is vertically positioned to one side of the first conveyor and is used to transport defective products. The visual inspection mechanism is located to one side of the first conveyor and is used to visually inspect test pieces. A photoelectric sensor is fixedly installed at the bottom of the first conveyor to determine whether a test piece has passed by. Through the combined action of a venturi tube and an adsorption tube, the pusher plate receives additional adsorption and fixation when pushing the test piece, minimizing the inertia of the test piece caused by the first conveyor during lateral pushing, thereby improving the stability and path accuracy of the test piece when pushed by the pusher plate.

Description

Technical Field

[0001] This invention relates to the field of sorting devices, specifically an automatic sorting device for visual inspection of surface defects in LED screens. Background Technology

[0002] LED displays are imaging devices composed of numerous LED display modules, widely used in advertising, information dissemination, and stage performances. During their manufacturing process, ensuring the consistency and reliability of the final product's display quality requires comprehensive surface defect inspection of each individual LED display module. This includes detecting defects such as bright spots, dark spots, scratches, dirt, and misaligned chip installations, thus accurately eliminating substandard products before assembly.

[0003] In existing technologies, the automatic sorting process after visual inspection of LED display modules typically employs two main methods. One method involves using an electric actuator to control a vertically deflectable guide plate; when the system determines a sample to be defective, the actuator raises the guide plate, altering the conveying path and guiding subsequent samples to the defective product collection line. The second method involves installing a high-speed cylinder on one side of the inspection conveyor line; once a defective sample is identified, the cylinder piston rod extends instantaneously, directly pushing the sample in the conveying state laterally into the adjacent defective product conveyor line or collection box.

[0004] However, during use and observation, it was found that all of the above sorting methods have obvious defects: the first method, which uses electric push rods to lift the guide plate, has a relatively slow mechanical response speed, making it difficult to meet the requirements of modern high-speed production lines; the second method, which uses cylinders for direct push, although it responds quickly, is prone to slippage and deviation due to inertia and insufficient friction with the conveyor belt surface, as the test pieces are pushed laterally during dynamic conveying. This results in inaccurate pushing positions and may even cause the test pieces to tip over or collide, affecting the reliability and accuracy of sorting.

[0005] Therefore, an automatic sorting device for visual inspection of surface defects in LED screens is proposed to address the above problems. Summary of the Invention

[0006] In order to overcome the shortcomings of the prior art, at least one technical problem raised in the background art is solved.

[0007] The technical solution adopted by this invention to solve its technical problem is as follows: An automatic sorting device for visual inspection of surface defects in LED screens, comprising a first conveyor, a visual inspection mechanism for visually inspecting test pieces is provided on the side of the first conveyor; and a second conveyor for conveying test pieces, the second conveyor being vertically arranged on one side of the first conveyor; the bottom of the first conveyor is also provided with an air guiding assembly for supplying air to a cylinder and adsorbing the test pieces; the air guiding assembly includes at least one Venturi tube; the Venturi tube includes an air inlet end connected to a solenoid valve, and another air outlet end for supplying air to the cylinder; the throat of the Venturi tube is fixed at the top and bottom respectively. The device includes a first riser and a second riser. An adsorption tube, communicating with a Venturi tube, slides through the first riser. An electromagnet is fixedly installed at the bottom of the second riser. A magnetic rod, repelled by the electromagnet's magnetism, slides along the inner wall of the second riser. A first spring is fixed between the outer wall of the magnetic rod and the inner wall of the second riser. The top of the magnetic rod and the bottom of the adsorption tube are fixedly connected by an extension rod. Through the combined action of the Venturi tube and the adsorption tube, the pusher plate receives additional adsorption and fixation when pushing the specimen, minimizing the inertia of the specimen from the first conveyor during lateral pushing, thereby improving the stability and path accuracy of the specimen when pushed by the pusher plate.

[0008] Preferably, the inner wall of the adsorption tube is provided with a sphere and a ball seat that fits against the sphere; a through hole is opened on the sphere; a first rotating shaft that penetrates the adsorption tube is fixedly connected to the outer wall of the sphere; a first support rod and a second support rod are fixedly connected to the outer wall of the first rotating shaft; a torsion spring is fixedly provided between the first rotating shaft and the outer wall of the adsorption tube; through the cooperation of the sphere and the first support rod, the adsorption tube can realize the timely opening and closing of the sphere according to whether there is a sample at the top, thereby reducing the adsorption tube's drowsy suction to the outside world and reducing the pollution of the airflow inside the Venturi tube by the outside airflow.

[0009] Preferably, a rotating wheel is provided at the end of the first support rod; considering that the specimen a always remains in contact with the first support rod when sliding, a rotating wheel can be provided at the end of the first support rod to reduce the frictional resistance between the two.

[0010] Preferably, a slide rail is fixed to the outer wall of the adsorption tube; a crossbar that slides with the slide rail is fixed to the outer wall of the second support rod; a guide wheel that rolls in the slide rail can be provided at the end of the crossbar. Through the sliding pair formed by the slide rail and the crossbar, the deflection amplitude of the second support rod can be constrained, thereby improving the stability and positional accuracy of the overall deflection of the first rotating shaft, the first support rod, and the second support rod.

[0011] Preferably, a sponge is fixed to the top of the adsorption tube; the sponge has a circular hole that coincides with the vertical projection of the through hole of the sphere; by setting the sponge, the sponge can fill and compensate for the gap error between the adsorption tube and the bottom of the specimen caused by processing through its own porous structure, so as to ensure the adsorption effect of the adsorption tube on the specimen.

[0012] Preferably, a pair of pistons are symmetrically slidably arranged on the inner wall of the push plate; a pair of pipe openings are provided on the top of the push plate, and the cavity between the pipe openings and the pair of pistons is connected; a second rotating shaft is symmetrically arranged on the inner wall of the push plate, and a transmission structure for driving the second rotating shaft to rotate is provided on the piston; a sliding plate is provided on the top of the second rotating shaft; a vertical rod is rotatably provided on the bottom of the sliding plate; the pair of vertical rods can deflect to both sides of the specimen to overcome the suction force applied to the specimen by the adsorption tube and clamp both sides of the specimen, so as to realize the adjustment and positioning of the specimen when pushing it, ensuring that the specimen is centered on one side of the push plate. In addition, considering the clamping force, a flexible layer can be provided on the vertical rods to reduce damage caused by excessive compression. Finally, the air can be vented through another pipe opening, and the piston is driven to reset by the elastic force of the second spring.

[0013] Preferably, a top plate is fixedly provided at the top of the second rotating shaft to slide in cooperation with the sliding plate; a third spring is fixedly provided between the sliding plate and the top plate; steel cables are symmetrically fixed at the top of the push plate; the ends of the steel cables are fixedly connected to the sliding plate; the ends of the top plate are rotatably provided with pulleys to constrain the steel cables; the third spring can apply a pushing force towards the upright to the sliding plate, so that the steel cables can slide in the top plate with the sliding plate, thereby enabling the clamping system composed of the sliding plate and the upright to expand outward when the second rotating shaft deflects, so as to improve the flexibility of the upright in centering and positioning specimens of different sizes. In addition, this arrangement also allows the clamping system composed of the sliding plate and the upright to be in a retracted state when the second rotating shaft does not deflect, reducing its occupied space.

[0014] Preferably, the inner wall of the push plate is provided with a circular plate; the outer wall of the circular plate is provided with a pair of cranks eccentrically and symmetrically; the ends of the cranks are rotatably connected to the outer wall of the piston; when the pair of pistons slide away from each other, the cranks will deflect along with the directly connected pistons. Since the cranks and the circular plate are rotatably connected, the pair of pistons can be forced to slide synchronously, ensuring the consistency of the rotation amplitude of the pair of second rotating shafts.

[0015] Preferably, the piston has at least one vent hole, and a valve is fixed to the inner wall of the vent hole. By setting the valve, the valve is in a closed state under normal conditions. Since the piston is in a stopped state after the upright clamps the specimen, as gas is continuously injected through the pipe, the pressure in the cavity between the pair of pistons can continue to rise. When a certain value is reached, the valve can expand under the action of air pressure and open the surface opening to relieve the pressure in the cavity between the pistons.

[0016] Preferably, the push plate has multiple grooves on the side facing the second conveyor that fit the shape of the upright, and the connection between the groove and the outer wall of the push plate is an arc transition. By setting the grooves, the upright can be tightly attached to the surface of the push plate in the initial state, so as to minimize the spatial interference of the upright on the first conveyor when the specimen is conveyed. In addition, the arc transition at the connection can also reduce the resistance between the upright and the push plate when the upright deflects.

[0017] The advantages of this invention are:

[0018] 1. The automatic sorting device for visual inspection of surface defects of LED screens according to the present invention, through the combined action of Venturi tube and adsorption tube, can make the pusher plate subject to additional adsorption and fixation when pushing the test piece, so as to minimize the inertia of the test piece caused by the first conveyor when pushing laterally, thereby improving the stability and path accuracy of the test piece when being pushed by the pusher plate.

[0019] 2. The LED screen surface defect visual inspection automatic sorting device of the present invention, through the cooperation of the ball and the first support rod, the adsorption tube can realize the timely opening and closing of the ball according to whether there is a test piece at the top, thereby reducing the adsorption tube's empty suction to the outside world and reducing the pollution of the airflow inside the Venturi tube by the outside airflow. Attached Figure Description

[0020] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0021] Figure 1 This is a schematic diagram of the main body of the present invention;

[0022] Figure 2 This is a schematic diagram of the structure of the first conveyor in this invention;

[0023] Figure 3 This is a schematic diagram of the cylinder structure in this invention;

[0024] Figure 4 This is a schematic diagram of the structure of the Chinese-language tube of the present invention;

[0025] Figure 5 This is a schematic diagram of the electromagnet structure in this invention;

[0026] Figure 6 This is a schematic diagram of the structure of the sphere in this invention;

[0027] Figure 7 This is a schematic diagram of the structure of the first rotating shaft in this invention;

[0028] Figure 8 This is a schematic diagram of the structure of the push plate in the first embodiment of the present invention;

[0029] Figure 9 This is a schematic diagram of the structure of the second embodiment of the push plate in this invention;

[0030] Figure 10 This is a schematic diagram of the valve structure in this invention;

[0031] Figure 11 This is a schematic diagram of the pulley structure in this invention.

[0032] In the diagram: 1. First conveyor; 12. Second conveyor; 13. Vision inspection mechanism; 15. Venturi tube; 16. First riser; 161. Second riser; 17. Adsorption tube; 18. Electromagnet; 19. Magnetic rod; 110. First spring; 111. Cylinder; 112. Push plate; 113. Orifice plate; 2. Sphere; 22. First shaft; 23. First support rod; 24. Second support rod; 25. Torsion spring; 3. Rotating wheel; 4. Slide rail; 42. Crossbar; 5. Sponge; 6. Pipe opening; 62. Piston; 63. Second shaft; 64. Stand; 65. Second spring; 7. Top plate; 72. Slide plate; 73. Steel cable; 74. Third spring; 75. Pulley; 8. Circular plate; 82. Crank; 9. Valve; a. Specimen. Detailed Implementation

[0033] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0034] Specific implementation examples are given below.

[0035] Please see Figures 1 to 11As shown in the embodiment of the present invention, an automatic sorting device for visual inspection of surface defects of LED screens includes a first conveyor 1, with a visual inspection mechanism 13 for visually inspecting test piece a disposed on the side of the first conveyor 1; a second conveyor 12 for conveying test piece a, and the second conveyor 12 being vertically disposed on one side of the first conveyor 1; a push plate 112 for pushing test piece a and a cylinder 111 for driving the push plate to move radially; the bottom of the first conveyor 1 is also provided with an air guiding assembly for supplying air to the cylinder 111 and adsorbing test piece a; the air guiding assembly includes at least one A venturi tube 15; the venturi tube 15 includes an inlet end connected to a solenoid valve and an outlet end for supplying air to cylinder 111; a first riser 16 and a second riser 161 are fixedly installed at the top and bottom of the throat of the venturi tube 15, respectively; an adsorption tube 17 connected to the venturi tube 15 is slidably inserted through the first riser 16; an electromagnet 18 is fixedly installed at the bottom of the second riser 161; a magnetic rod 19 that is magnetically repelled by the electromagnet 18 is slidably installed on the inner wall of the second riser 161; a first spring 110 is fixedly installed between the outer wall of the magnetic rod 19 and the inner wall of the second riser 161; the top of the magnetic rod 19 and the bottom of the adsorption tube 17 are fixedly connected by an extension rod.

[0036] During testing, specimen a is transported to the first conveyor 1 via the upstream conveyor mechanism. Specimen a can pass through the vision inspection mechanism 13 and be photographed by the vision inspection mechanism 13. The vision inspection mechanism 13 specifically includes an industrial camera, which can quickly take pictures of specimen a and obtain high-definition images with the help of a light source. After taking pictures, the vision inspection mechanism 13 can transmit the images to the industrial control computer. The vision processing software built into the industrial control computer can analyze the images and determine whether there are surface defects such as scratches or dirt in the current module. According to the analysis results, no response is made for good products and the process continues. For defective products, the industrial control computer sends an electrical signal to the solenoid valve connected to the air guide assembly, which drives the air guide assembly to supply air to the cylinder 111 and adsorb the defective product. The push plate 112 is then driven to push the defective product laterally to the second conveyor 12. The above-mentioned procedures and logical sequences are mature existing technologies and will not be elaborated here.

[0037] The working principle of the above-mentioned air guiding component is as follows: In the initial state, the component consisting of the adsorption tube 17 and the magnetic rod 19 is located at the bottom of the second riser 161. When the defective product passes through the visual inspection mechanism 13, the solenoid valve can be energized and the compressed airflow flows into the venturi tube 15. The air source here can be an air compressor or a high-pressure gas cylinder. When the airflow passes through the throat of the venturi tube 15, the airflow will change from coarse to fine and the flow rate will increase. The gas forms a "vacuum" zone at the "rear" side of the outlet, that is, the top of the adsorption tube 17 connected to the venturi tube 15 can generate negative pressure. When the solenoid valve is energized, the electromagnet 18 can be energized simultaneously, driving the magnetic rod 19 and the directly connected adsorption tube 161. 7. Under the action of magnetic force, the magnetic rod 19 and the adsorption tube 17 are lifted. Due to the setting of the perforated plate 113, the sliding range of the magnetic rod 19 and the adsorption tube 17 is limited. That is, the highest point of the adsorption tube 17 can be pressed against the bottom of the specimen a, so that the adsorption tube 17 can adsorb and fix the specimen a through negative pressure. In addition, the perforated plate 113 can be fixedly set on the outer wall of the magnetic rod 19, and the limiting measures can be set in the second vertical tube 161 and the first vertical tube 16 to constrain the sliding range of the magnetic rod 19 through the perforated plate 113. The above movement process takes several milliseconds. Therefore, it can be understood that the outline of the specimen a will be adsorbed by the adsorption tube 17 as soon as it passes the visual inspection mechanism 13. Compressed airflow enters cylinder 111 through the outlet of venturi tube 15 (not shown in the above-mentioned piping diagram involving airflow), driving push plate 112 to move radially. Since specimen a is adsorbed and fixed by adsorption tube 17 and pauses on the first conveyor 1, and because the pressure exerted by the compressed airflow on push plate 112 is much greater than the suction force of adsorption tube 17 on specimen a, push plate 112 can laterally push specimen a, which is currently in an adsorption paused state, onto the second conveyor 12. It is worth mentioning that the factors limiting the adsorption effect of adsorption tube 17 on specimen a are roughly the air pressure intensity and the conveying speed of the first conveyor 1. In actual use… At the same time, the adsorption effect of the adsorption tube 17 on the specimen a can be ensured by increasing the air pressure intensity or reducing the speed of the first conveyor 1. In addition, the bottom shell support of the specimen a should be selected with a flat bottom surface to ensure the adsorption effect. In addition, the exhaust method in the cylinder 111 can be set in the same way as the existing technology, which will not be elaborated here. Through the cooperation of the venturi tube 15 and the adsorption tube 17, the pusher plate 112 can be subjected to additional adsorption and fixation when pushing the specimen a, so as to minimize the inertia of the first conveyor 1 when the specimen a is pushed laterally, thereby improving the stability and path accuracy of the specimen a when pushed by the pusher plate 112.

[0038] Please see Figures 5 to 7 As shown, the inner wall of the adsorption tube 17 is provided with a sphere 2 and a ball seat that fits against the sphere 2; a through hole is opened on the sphere 2; a first rotating shaft 22 that penetrates the adsorption tube 17 is fixedly connected to the outer wall of the sphere 2; a first support rod 23 and a second support rod 24 are fixedly connected to the outer wall of the first rotating shaft 22; a torsion spring 25 is fixedly provided between the first rotating shaft 22 and the outer wall of the adsorption tube 17.

[0039] When specimen a leaves the adsorption tube 17 under the pushing action of the pusher plate 112, the adsorption tube 17 will continuously draw in air from the outside. In the initial state, such as Figure 6 As shown, the second support rod 24 is vertical under its own weight, while the first support rod 23 is inclined. The through hole on the sphere 2 is not connected to the ball seat. When the electromagnet 18 is activated, the first support rod 23 will rise with the adsorption tube 17 and contact the bottom of the specimen a. Under the squeezing action, the first support rod 23, the first rotating shaft 22, and the second support rod 24 can be deflected to the following position: Figure 7 As shown, the sphere 2 and the adsorption tube 17 are in a connected state at this time, that is, the adsorption tube 17 is in an open state. This setting allows the adsorption tube 17 to be in an open state when the sample a is at the top of the adsorption tube 17. When the push plate 112 pushes the sample a completely away from the adsorption tube 17, the first rotating shaft 22 can be reset under the elastic force of the torsion spring 25 and the sphere 2 can be closed to the adsorption tube 17 to prevent the adsorption tube 17 from continuously sucking in air and causing impurities to enter the adsorption tube 17 and the venturi tube 15. In addition, the lever formed by the first support rod 23 can amplify the deflection force exerted by the sample a on the first rotating shaft 22 and the sphere 2, making it easier to control the opening and closing of the sphere 2. Through the cooperation of the sphere 2 and the first support rod 23, the adsorption tube 17 can be opened and closed in time according to whether there is a sample a at the top, reducing the adsorption tube 17's empty suction to the outside world and reducing the pollution of the airflow inside the venturi tube 15 by the outside airflow.

[0040] Please see Figure 6 and Figure 7 As shown, a rotating wheel 3 is rotatably provided at the end of the first support rod 23;

[0041] Considering that the specimen a always remains in contact with the first support rod 23 during sliding, a rotating wheel 3 can be provided at the end of the first support rod 23 to reduce the frictional resistance between them.

[0042] Please see Figure 6 and Figure 7 As shown, a slide rail 4 is fixedly connected to the outer wall of the adsorption tube 17; a crossbar 42 that slides with the slide rail 4 is fixedly connected to the outer wall of the second support rod 24.

[0043] The end of the crossbar 42 may be provided with a guide wheel that rolls in the slide rail 4. Through the sliding pair formed by the slide rail 4 and the crossbar 42, the deflection amplitude of the second support rod 24 can be constrained, thereby improving the stability and positional accuracy of the overall deflection of the first rotating shaft 22, the first support rod 23, and the second support rod 24.

[0044] Please see Figure 6 and Figure 7 As shown, a sponge 5 is fixed to the top of the adsorption tube 17; a circular hole is opened on the sponge 5 that coincides with the vertical projection of the through hole of the sphere 2.

[0045] By setting up the sponge 5, the sponge 5 can fill and compensate for the gap error between the adsorption tube 17 and the bottom of the specimen a due to processing through its own porous structure, so as to ensure the adsorption effect of the adsorption tube 17 on the specimen a. In addition, considering that the sponge 5 is easily contaminated, the sponge 5 and the adsorption tube 17 can be bonded together, that is, the old sponge 5 can be peeled off and disassembled by using a scraper.

[0046] Please see Figures 8 to 11 As shown, a pair of pistons 62 are symmetrically slidably arranged on the inner wall of the push plate 112; a pair of pipe openings 6 are provided on the top of the push plate 112, and the cavity between the pipe openings 6 and the pair of pistons 62 is connected; a second rotating shaft 63 is symmetrically arranged on the inner wall of the push plate 112, and a transmission structure for driving the second rotating shaft 63 to rotate is provided on the piston 62; a sliding plate 72 is provided on the top of the second rotating shaft 63; and a vertical rod 64 is rotatably provided on the bottom of the sliding plate 72.

[0047] Considering that the defective sample a is in a conveying state and is adsorbed and fixed by the adsorption tube 17, the posture of sample a is uncertain during the conveying process. Therefore, additional technical means are needed to ensure the centering of sample a when it is pushed by the pusher plate 112. This invention provides two implementation methods. The first implementation method can be referred to. Figure 8 A V-shaped guide block is integrated on the side of the push plate 112 facing the specimen a. The V-shaped symmetrical inclined surface is used to center the specimen a when pushing it. However, if the specimen a starts to deviate too far from the center of the push plate 112, the V-shaped guide block will apply a rotational torque to the specimen a, causing the specimen a to become more and more tilted as it is pushed.

[0048] The second implementation method can be referred to. Figures 9 to 11 The specific working principle is as follows:

[0049] In the initial state, the upright 64 is set tightly against the push plate 112. One port 6 on the push plate 112 is used for air intake and can be connected to the air outlet of the solenoid valve connected to the venturi tube 15. The other port 6 is used for exhaust and can be opened and closed electrically. This is not shown here. When the solenoid valve is activated, the specimen a should be located in the middle area of ​​the push plate 112 and be attracted by the adsorption tube 17. Part of the airflow flows towards the venturi tube 15, and part of the airflow flows into the push plate 112 through the port 6. A pair of pistons 62 can slide away from each other under air pressure. During the process, the pistons 62 can drive the second rotating shaft 63 to rotate through the transmission structure. The transmission structure here can be a gear and rack transmission as shown in the figure. The second rotating shaft 63 can be driven by the top sliding plate. 72 drives the upright rod 64 to deflect inward to the inside of the push plate 112, that is, a pair of upright rods 64 can deflect to both sides of the specimen a, overcome the suction force applied to the specimen a by the adsorption tube 17 and clamp the two sides of the specimen a, so as to adjust and position the posture of the specimen a when pushing it, and ensure that the specimen a is centered on one side of the push plate 112. At the same time, since the upright rod 64 is rotated at the bottom of the slide plate 72, the specimen a will not be subjected to too much resistance applied by the upright rod 64 when it moves away from the push plate 112 under the conveying action of the second conveyor 12. In addition, considering the clamping force, a flexible layer can be set on the upright rod 64 to reduce the damage caused by excessive compression. Finally, the exhaust can be discharged through another pipe 6, and the piston 62 is automatically reset by the elastic force of the second spring 65.

[0050] Based on the comparison of the two implementation methods above, and considering the long-term implementation of the centering effect of specimen a, the second implementation method is preferred.

[0051] Regarding the service life of the mechanism in the second embodiment, firstly, since the application scenario of this mechanism is the detection and sorting of LED display modules, the impact and vibration that can be exerted by the external environment can be ignored. Secondly, the principle of driving the piston 62 to rotate the rod 64 by pneumatic drive is the same as the rotary cylinder in the prior art. That is, the wear and leakage that may occur when these components are working are all within the scope of reasonable design.

[0052] Please see Figures 8 to 10 As shown, a top plate 7 is fixedly provided on the top of the second rotating shaft 63, which slides and engages with the slide plate 72; a third spring 74 is fixedly provided between the slide plate 72 and the top plate 7; steel cables 73 are symmetrically fixed on the top of the push plate 112; the end of the steel cable 73 is fixedly connected to the slide plate 72; and a pulley 75 is rotatably provided on the end of the top plate 7 to constrain the steel cable 73.

[0053] by Figure 10For example, when the second rotating shaft 63 is not deflected, the angle between the pulley 75 directly connected to its end and the fixed point of the steel cable 73 on the push plate 112 is the largest, that is, the length of the steel cable 73 exposed to the outside is the longest. At this time, the third spring 74 is in a compressed state. As the second rotating shaft 63 deflects counterclockwise, the angle between the pulley 75 and the steel cable 73 can gradually decrease, and the tension applied by the steel cable 73 to the slide plate 72 will also weaken. During the process, the third spring 74 can apply a pushing force towards the upright 64 to the slide plate 72, so that the steel cable 73 can slide in the top plate 7 with the slide plate 72. Thus, when the second rotating shaft 63 deflects, the clamping system composed of the slide plate 72 and the upright 64 can perform outward expansion movement to improve the flexibility of the upright 64 in centering and positioning specimens a of different sizes. In addition, this setting can also make the clamping system composed of the slide plate 72 and the upright 64 in a retracted state when the second rotating shaft 63 is not deflected, reducing its occupied space.

[0054] Please see Figure 8 and Figure 9 As shown, a circular plate 8 is rotatably provided on the inner wall of the push plate 112; a pair of cranks 82 are eccentrically and symmetrically rotatably provided on the outer wall of the circular plate 8; the ends of the cranks 82 are rotatably connected to the outer wall of the piston 62.

[0055] When a pair of pistons 62 slide in opposite directions, the crank 82 will deflect along with the directly connected piston 62. Since the crank 82 and the circular plate 8 are both rotatably connected, the pair of pistons 62 can be forced to slide synchronously, ensuring the consistency of the rotation amplitude of a pair of second rotating shafts 63.

[0056] Please see Figure 8 and Figure 9 As shown, the piston 62 has at least one exhaust port, and a valve 9 is fixed to the inner wall of the exhaust port.

[0057] By setting valve 9, valve 9 is in a closed state under normal conditions. After the upright rod 64 clamps the specimen a, piston 62 is in a stopped state. As gas is continuously injected through the port 6, the pressure in the cavity between a pair of pistons 62 can continue to rise. When it reaches a certain value, valve 9 can expand under the action of air pressure and open the surface opening to relieve pressure in the cavity between pistons 62.

[0058] Please see Figure 8 As shown, the push plate 112 has multiple grooves on the side facing the second conveyor 12 that fit the shape of the upright 64, and the grooves are connected to the outer wall of the push plate 112 with an arc transition.

[0059] By setting the groove, the upright 64 can be tightly attached to the surface of the push plate 112 in the initial state, so as to minimize the spatial interference of the specimen a with the upright 64 when it is conveyed on the first conveyor 1. In addition, the arc transition at the connection can also reduce the resistance between the upright 64 and the push plate 112 when the upright 64 deflects.

[0060] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the claimed invention.

Claims

1. An LED screen surface defect visual inspection automatic sorting device, characterized in that: The first conveyor (1) is provided with a visual inspection mechanism (13) for visual inspection of the test piece (a) on the side of the first conveyor (1), and a second conveyor (12) for conveying the test piece (a) is vertically arranged on one side of the first conveyor (1), and a push plate (112) for pushing the test piece (a) and a cylinder (111) for driving the radial movement of the push plate are arranged on the second conveyor (12). The bottom of the first conveyor (1) is further provided with an air guide assembly for supplying air to the cylinder (111) and adsorbing the test piece (a); the air guide assembly comprises at least one Venturi tube (15); the Venturi tube (15) comprises an air inlet end communicated with a solenoid valve and an air outlet end for supplying air to the cylinder (111). The throat of the Venturi tube (15) is fixed with a first vertical pipe (16) and a second vertical pipe (161) respectively; the first vertical pipe (16) is slidably provided with an adsorption pipe (17) communicated with the Venturi tube (15); the bottom of the second vertical pipe (161) is fixedly provided with an electromagnet (18); the inner wall of the second vertical pipe (161) is slidably provided with a magnetic rod (19) repelling the electromagnet (18); the first spring (110) is fixed between the outer wall of the magnetic rod (19) and the inner wall of the second vertical pipe (161); the top of the magnetic rod (19) and the bottom of the adsorption pipe (17) are fixedly connected by an extension rod. 2.The LED screen surface defect visual inspection and automatic sorting device according to claim 1, characterized in that: The inner wall of the adsorption pipe (17) is provided with a ball (2) and a ball seat adhering to the ball (2); a through hole is formed in the ball (2); the outer wall of the ball (2) is fixedly connected with a first rotating shaft (22) penetrating the adsorption pipe (17); the outer wall of the first rotating shaft (22) is fixedly connected with a first branch rod (23) and a second branch rod (24); the first rotating shaft (22) and the outer wall of the adsorption pipe (17) are fixedly provided with a torsional spring (25). 3.The LED screen surface defect visual inspection and automatic sorting device according to claim 2, characterized in that: The end of the first branch rod (23) is rotatably provided with a rotating wheel (3).

4. The LED screen surface defect visual inspection and automatic sorting device according to claim 3, characterized in that: The outer wall of the adsorption pipe (17) is fixedly connected with a sliding rail (4); the outer wall of the second branch rod (24) is fixedly connected with a cross rod (42) slidably matched with the sliding rail (4).

5. The LED screen surface defect visual inspection and automatic sorting device according to claim 4, characterized in that: The top of the adsorption pipe (17) is fixedly connected with a sponge (5); a circular hole is formed in the sponge (5) vertically coinciding with the through hole of the ball (2).

6. The LED screen surface defect visual inspection and automatic sorting device according to claim 5, characterized in that: A pair of pistons (62) are symmetrically slidably arranged in the inner wall of the push plate (112); a pair of pipe mouths (6) are arranged on the top of the push plate (112), and the cavities between the pipe mouths (6) and the pair of pistons (62) are in communication; a second rotating shaft (63) is symmetrically arranged in the inner wall of the push plate (112), and a transmission structure for driving the second rotating shaft (63) to rotate is arranged on the piston (62); a sliding plate (72) is arranged on the top of the second rotating shaft (63); a vertical rod (64) is rotatably arranged on the bottom of the sliding plate (72).

7. The LED screen surface defect visual inspection and automatic sorting device according to claim 6, characterized in that: The second rotating shaft (63) is fixed at the top with a top plate (7) which is in sliding fit with a sliding plate (72); a third spring (74) is fixed between the sliding plate (72) and the top plate (7); the top of the push plate (112) is fixed symmetrically with a steel cable (73); the end of the steel cable (73) is in fixed connection with the sliding plate (72); the end of the top plate (7) is rotatably provided with a pulley (75) which restricts the steel cable (73). 8.The LED screen surface defect visual inspection and automatic sorting device according to claim 7, characterized in that: The inner wall of the push plate (112) is rotatably provided with a circular plate (8); the outer wall of the circular plate (8) is eccentrically and symmetrically rotatably provided with a pair of cranks (82); the end of the crank (82) is rotatably connected with the outer wall of the piston (62).

9. The LED screen surface defect visual inspection and automatic sorting device according to claim 8, characterized in that: At least one exhaust hole is formed in the piston (62), and a valve (9) is fixedly connected to the inner wall of the exhaust hole.

10. The LED screen surface defect visual inspection and automatic sorting device according to claim 9, characterized in that: The side of the push plate (112) facing the second conveyor (12) is provided with a plurality of recesses which are in fit with the shape of the vertical rod (64), and the recesses are in arc-shaped transition with the outer wall of the push plate (112).

Images