An automatic grading and sorting device for green onions based on machine vision

Abstract

The application discloses a kind of automatic classification and sorting device of machine vision based on big green onion, including conveyor belt, grading detection mechanism, baffle and grading sorting unit, the conveyor belt is used to transport big green onion, the band body outer wall of the conveyor belt is fixedly connected with several partition plates at equal intervals, the accommodating cavity for accommodating big green onion is formed between the band body of adjacent two partition plates, the grading detection mechanism includes the detection box of being sleeved to the outside of conveyor belt, the inside top of the detection box is fixedly connected with mounting plate, the mounting plate is also inclined and is consistent with the inclination angle of conveyor belt, industrial camera is installed in the bottom of the mounting plate, the full automation process of first visual detection grading, after fixed point automatic shunting is formed, without manual sorting, manual specification, realize big green onion multidimensional automatic classification and sorting, reduce labor cost, improve sorting efficiency.

Description

Technical Field

[0001] This invention belongs to the technical field of agricultural product grading and sorting equipment, specifically relating to an automatic grading and sorting device for scallions based on machine vision. Background Technology

[0002] Scallions are a fresh vegetable with a large planting and distribution scale in my country. Grading and sorting after harvesting are the core processes to improve the added value of the product and ensure the effect of storage and preservation. Affected by growth factors such as light, water and fertilizer, scallions generally have uneven thickness and length after harvesting. The storage resistance and market price of scallions of different specifications are significantly different. Mixing them will not only accelerate the deterioration of high-quality scallions and shorten the overall shelf life, but also lead to insufficient product premium, directly affecting the economic benefits of planting and distribution. As scallion planting develops towards large-scale and industrialized development, the traditional sorting model is no longer able to meet the needs of mass production.

[0003] Currently, scallion sorting mainly relies on two solutions: manual labor and traditional mechanical equipment. Manual sorting depends on experience to judge the size of scallions and sort them manually, which is inefficient and labor-intensive. Moreover, the grading standards are affected by the subjective state of the operator, resulting in poor consistency of finished product specifications. With the continuous rise in labor costs, it can no longer meet the needs of large-scale continuous operation. Traditional mechanical grading equipment mostly uses structures such as drum screening and roller diameter sorting, which can only perform rough grading according to the maximum outer diameter or length. The grading dimension is single and cannot accurately identify fine indicators such as the diameter of the white part of the scallion and appearance defects. In addition, hard contact sorting is prone to causing scallion leaf breakage and white part skin abrasion, which greatly reduces the appearance and shelf life of the product and causes unnecessary economic losses.

[0004] Therefore, there is an urgent need to design an automatic grading and sorting device for scallions based on machine vision to improve the above problems. Summary of the Invention

[0005] To address the shortcomings of existing technologies, the present invention aims to provide an automatic grading and sorting device for scallions based on machine vision, which solves the problems of low efficiency and high labor intensity caused by excessive reliance on manual labor in the grading and sorting of scallions in existing technologies.

[0006] To address the aforementioned technical problems, this invention provides an automatic grading and sorting device for scallions based on machine vision, comprising: A conveyor belt for transporting scallions. The conveyor belt is inclined along the transport direction. A support frame is fixedly connected to the bottom of the conveyor belt. Several partition plates are fixedly connected at equal intervals on the outer wall of the conveyor belt. An accommodating cavity for accommodating scallions is formed between two adjacent partition plates and the belt body. A grading and testing mechanism includes a testing box fitted on the outside of a conveyor belt. Connecting legs are fixedly connected to both sides of the bottom of the testing box. The connecting legs are fixedly connected to a support frame. An installation plate is fixedly connected to the top of the inside of the testing box. The installation plate is also inclined and has the same inclination angle as the conveyor belt. An industrial camera is installed at the bottom of the installation plate. A baffle is provided along the length of the conveyor belt and is located at the lower end of the conveyor belt. The baffle is also inclined and has the same inclination angle as the conveyor belt. The baffle is fixedly connected to the support frame by a fixing frame. The grading and sorting unit includes an intermediate grading and sorting unit and a tail-end grading and sorting unit. The tail-end grading and sorting unit is located at the discharge end of the conveyor belt. Multiple sets of intermediate grading and sorting units are arranged between the detection box and the tail-end grading and sorting units. The intermediate grading and sorting unit includes a discharge mechanism on a baffle, a positioning blowing mechanism on the conveyor belt, and a receiving mechanism. The tail-end grading and sorting unit includes a receiving mechanism.

[0007] Preferably, the separator plate is equipped with an electronic tag at the higher end of the conveyor belt, and a first RFID reader is installed at the bottom of the mounting plate corresponding to the position of the electronic tag.

[0008] Preferably, the positioning blowing mechanism includes a mounting frame fixedly connected to the back of the support frame, and a second RFID reader corresponding to the position of the electronic tag is installed at the top of the mounting frame.

[0009] Preferably, the top of the baffle is provided with a discharge port, and the discharge mechanism includes a discharge port baffle disposed inside the discharge port. The bottom end of the discharge port baffle is rotatably connected to the baffle. A fixing rod is fixedly connected to the outside of the discharge port baffle. A cylinder is installed on the outer wall of the baffle below the discharge port. The output end of the cylinder is hinged to the end of the fixing rod away from the discharge port baffle with a hinge rod.

[0010] Preferably, a limiting block is fixedly connected to the outer wall of the discharge port baffle, and both ends of the limiting block extend to the outside of the discharge port baffle.

[0011] Preferably, the discharge mechanism further includes a discharge pipe fixedly connected to the outer wall of the baffle and located around the discharge port. The discharge pipe is inclined, and a clearance groove is provided at the end of the discharge pipe near the baffle for the movement of the fixing rod and the hinge rod.

[0012] Preferably, the positioning blowing mechanism further includes a blowing nozzle mounted on the mounting frame, wherein the blowing direction of the blowing nozzle is towards the discharge port.

[0013] Preferably, supplementary lights are installed on both sides of the bottom of the mounting plate located on the industrial camera.

[0014] Preferably, the receiving mechanism of the intermediate grading and sorting unit is used to collect the scallion material discharged from the discharge pipe, and the receiving mechanism of the tail-end grading and sorting unit is used to collect the scallion material discharged from the tail end of the conveyor belt. The receiving mechanism includes a receiving base, two placement seats are provided on the top of the receiving base, a receiving box is embedded in the top of the placement seats, a screw groove is opened along the length direction on the top of the receiving base, a screw is rotatably connected in the screw groove, a drive motor is installed on one side of the receiving base, the output end of the drive motor is fixedly connected to one end of the screw, a threaded sleeve is fixedly connected to the bottom of the placement seat and placed in the screw groove and threadedly connected to the screw, guide grooves are opened on both sides of the screw groove on the top of the receiving base, guide rods are fixedly connected in the guide grooves, and a guide sleeve is fixedly connected to the bottom of the placement seat and placed in the guide groove and slidably connected to the guide rod.

[0015] Preferably, a set of the placement base and the receiving box constitutes a receiving station, and the length of the receiving base is sufficient to accommodate three receiving stations.

[0016] Compared with the prior art, the beneficial effects of the present invention are as follows: This invention uses an inclined conveyor belt and partitions to form independent cavities that constrain the posture of scallions, preventing them from rolling, slipping, or tangling during transport. This ensures that each scallion remains independent and uniformly positioned as it is continuously transported to the grading and inspection mechanism. Physically separating each scallion guarantees individual imaging and sorting, reducing the probability of visual misjudgment and misclassification from the source. The industrial camera in the grading and inspection mechanism acquires the scallion's appearance parameters and determines its grade, providing sorting instructions to the downstream sorting unit. The graded scallions are matched using electronic tags, a first RFID reader, and a second RFID reader. The grading and sorting unit receives the grading instructions from the grading and inspection mechanism and completes the sorting and aggregation of scallions of the corresponding grades. This forms a fully automated process of visual inspection and grading followed by fixed-point automatic sorting, eliminating the need for manual sorting and specification differentiation. This achieves multi-dimensional automatic grading and sorting of scallions, reducing labor costs and improving sorting efficiency. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the overall structure of the automatic scallion grading and sorting device based on machine vision according to the present invention. Figure 2 This is a top view of the automatic grading and sorting device for scallions based on machine vision according to the present invention. Figure 3 This is a side view of the automatic grading and sorting device for scallions based on machine vision according to the present invention. Figure 4 This is a schematic diagram of the cross-sectional structure of the conveyor belt of the present invention; Figure 5 This is a schematic diagram of the grading detection mechanism of the present invention; Figure 6 This is a schematic diagram of the baffle and discharge mechanism of the present invention; Figure 7 This is a schematic diagram of the overall structure of the discharge mechanism of the present invention; Figure 8 This is a schematic diagram of the material discharge mechanism of the present invention. Figure 9 This is a schematic diagram of the positioning and blowing mechanism of the present invention; Figure 10 This is a schematic diagram of the material receiving mechanism of the present invention.

[0018] The labels in the attached diagram are: 1. Conveyor belt; 101. Support frame; 102. Divider plate; 1021. Electronic tag; 2. Baffle; 201. Fixing frame; 202. Discharge port; 3. Grading and detection mechanism; 301. Detection box; 302. Connecting support leg; 303. Mounting plate; 304. Industrial camera; 305. First RFID reader / writer; 306. Fill light; 4. Discharge mechanism; 401. Discharge port baffle; 402. Fixing rod; 403. Cylinder; 404. Hinge rod; 405. Limiting block; 406. Discharge pipe; 5. Positioning blowing mechanism; 501. Mounting frame; 502. Second RFID reader / writer; 503. Blowing nozzle; 6. Receiving mechanism; 601. Receiving base; 602. Placement seat; 603. Lead screw; 604. Guide rod; 605. Drive motor; 606. Receiving box. Detailed Implementation

[0019] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention.

[0020] Example: Please refer to Figures 1-10This embodiment provides an automatic grading and sorting device for scallions based on machine vision, including a conveyor belt 1, a grading and detection mechanism 3, baffles 2, and a grading and sorting unit. The conveyor belt 1 is used to transport scallions and is inclined along the conveying direction. A support frame 101 is fixedly connected to the bottom of the conveyor belt 1, and the support frame 101 is welded and fixed to the frame of the conveyor belt 1. Several partition plates 102 are fixedly connected at equal intervals on the outer wall of the conveyor belt 1. Adjacent partition plates 102 and the belt body form a receiving cavity for accommodating scallions. The baffles 2 are inclined along the conveyor belt 1. Conveyor belt 1 is positioned along its length and located at the lower end of conveyor belt 1. Baffle 2 is also inclined and at the same angle as conveyor belt 1. Baffle 2 is fixedly connected to support frame 101 via fixing frame 201. Fixing frame 201 is welded to baffle 2 and fixed to support frame 101 via bolts. The operator places single scallions one by one from the feed end of conveyor belt 1 into the receiving cavity formed between two adjacent partition plates 102 and the belt body. The inclined conveyor belt 1 transports the scallions at a uniform speed, with the roots of the scallions resting against the... On baffle 2, the scallions are prevented from sliding outwards onto the conveyor belt 1, providing lateral restraint and straightening for the long scallions. During transport, each separator 102 physically separates the scallions in front and behind. The inclined conveyor belt 1, together with the independent cavities formed by the separators 102, constrains the posture of the scallions, preventing them from rolling, slipping, or tangling and stacking during transport. This ensures that each scallion remains independent and maintains a uniform posture as it is continuously transported to the grading and inspection mechanism 3. Physically separating each scallion ensures that each scallion is imaged and sorted individually, reducing the risk of contamination at the source. The probability of visual recognition errors and misclassifications is reduced. The grading and detection mechanism 3 is responsible for acquiring the appearance parameters of the scallions and determining their specifications and grades, providing sorting instructions to the back-end sorting unit. The grading and sorting unit is the execution mechanism that performs sorting, unloading, and classifying and collecting finished products. It receives the grading instructions issued by the grading and detection mechanism 3 and completes the diversion and collection of scallions of corresponding specifications, forming a fully automated process of first visual detection and grading, and then fixed-point automatic diversion. There is no need for manual sorting or manual specification differentiation, realizing multi-dimensional automatic grading and sorting of scallions, reducing labor costs and improving sorting efficiency.

[0021] In this embodiment, as Figure 1 and Figure 5As shown, the grading and inspection mechanism 3 includes an inspection box 301 fitted onto the outside of the conveyor belt 1. Connecting legs 302 are fixedly connected to both sides of the bottom of the inspection box 301. The connecting legs 302 are fixedly connected to the support frame 101. One end of the connecting legs 302 is welded to the inspection box 301, and the other end is bolted to the support frame 101. A mounting plate 303 is fixedly connected to the top of the interior of the inspection box 301. The mounting plate 303 is bolted to the inspection box 301. The mounting plate 303 is also inclined and its angle matches that of the conveyor belt 1. An industrial camera 304 is mounted on the bottom of the mounting plate 303. The inclined mounting plate 303, fixed to the top of the interior of the inspection box, matches the angle of the mounting plate 303 to the conveyor belt 1, ensuring that the lens of the industrial camera 304 is perpendicularly facing the surface of the conveyor belt 1 below, thus reducing costs. Like distortion, the scallions are conveyed at a uniform speed by the inclined conveyor belt 1, entering the closed detection area inside the detection box 301 from one end. Under the support of the partition plate 102, they maintain a stable posture and continue to move forward. The detection box 301 forms an independent and closed imaging space, which can isolate the interference of natural light and ambient light in the workshop, avoid shadows and reflections caused by uneven lighting, ensure that the lighting conditions are consistent for each scallion, and improve the stability and accuracy of visual inspection. When the receiving cavity carrying the scallions passes directly below the industrial camera 304, the industrial camera 304 takes a complete picture of a single scallion, obtaining a scallion appearance image with uniform proportions, clarity and no distortion. The industrial camera 304 transmits the acquired scallion image data to the back-end control and recognition system, providing raw visual data support for subsequent scallion size calculation and grade determination.

[0022] In the specific implementation process, the industrial camera 304 can be a global shutter area array industrial camera, such as Hikvision MV-CH120-10GM, Dahua Huarui A5201MG500, etc. The industrial camera 304 acquires images and transmits them to the industrial control vision algorithm to extract the visual information of the scallion for classification. For example, it can be classified according to the diameter of the white part of the scallion or the length of the whole plant. The pixels of the white part of the scallion are extracted, the diameter of the white part of the scallion is calculated, the overall outline of the scallion is identified, the total length of the whole plant is calculated, and the classification is automatically determined according to the preset classification threshold. Of course, it is also applicable to other vision classification methods. This is the existing technology and will not be elaborated on here.

[0023] In this embodiment, as Figure 5 As shown, the bottom of the mounting plate 303 is equipped with supplementary lights 306 on both sides of the industrial camera 304. The supplementary lights 306 illuminate the scallion plant, allowing the industrial camera to capture scallion images with clear outlines, uniform brightness, and sharp edges, providing a high-quality raw image basis for subsequent visual algorithms to extract the length of the whole plant and calculate the diameter of the white part of the scallion.

[0024] In this embodiment, as Figure 1 and Figure 2As shown, the grading and sorting unit includes an intermediate grading and sorting unit and a tail-end grading and sorting unit. The tail-end grading and sorting unit is located at the discharge end of the conveyor belt 1. Multiple intermediate grading and sorting units are located between the detection box 301 and the tail-end grading and sorting units. Each intermediate grading and sorting unit includes a discharge mechanism 4 mounted on the baffle 2, a positioning blowing mechanism 5 mounted on the conveyor belt 1, and a receiving mechanism 6. Each tail-end grading and sorting unit includes the receiving mechanism 6. Each intermediate grading and sorting unit corresponds to a preset scallion grading level. The tail-end grading and sorting unit is located at the discharge port at the very end of the conveyor belt, responsible for collecting any remaining scallion material. After the grading and detection mechanism 3 completes the scallion grading determination, the grading information is simultaneously conveyed to the grading and sorting unit along with the scallions. The sorting unit is an independent functional module, and the number of groups can be flexibly increased or decreased according to actual grading needs. It is suitable for different scenarios from two-level basic grading to multi-level refined grading. It adopts a unidirectional linear layout of detection grading - grade-by-grade sorting - end collection. The green onions pass through each grade sorting station in sequence along the conveying direction. If they match, they are discharged; if they do not match, they are released. Finally, the remaining green onion material is collected by the tail-end grading and sorting unit. The positioning blowing mechanism 5 is used to position the green onions that have been graded by the grading detection mechanism 3 at the corresponding intermediate grading and sorting unit. Then, the discharge mechanism 4 in the corresponding intermediate grading and sorting unit opens and discharges the green onions from the conveyor belt 1. They are then collected by the receiving mechanism 6 in the corresponding intermediate grading and sorting unit, realizing continuous grading and sorting of large batches of green onions.

[0025] In this embodiment, as Figure 1 , Figure 5 and Figure 9As shown, an electronic tag 1021 is installed on the higher end of the partition plate 102 on the conveyor belt 1. A first RFID reader 305 corresponding to the position of the electronic tag 1021 is installed on the bottom of the mounting plate 303. The positioning blowing mechanism 5 includes a mounting frame 501 fixedly connected to the back of the support frame 101. The mounting frame 501 is fixedly connected to the support frame 101 by bolts. A second RFID reader 502 corresponding to the position of the electronic tag 1021 is installed on the top of the mounting frame 501. The electronic tag 1021 with a unique identification code is set on each partition plate 102. 02. Near the high end of the conveyor belt, calibrate the installation height and horizontal position of the first RFID reader 305 and the second RFID reader 502 so that their reading range covers the running trajectory of the electronic tag 1021, ensuring stable and reliable reading of the electronic tag 1021 during the conveying process. When the partition plate 102 carrying the scallions enters the grading and detection mechanism 3 along the inclined conveyor belt 1, the first RFID reader 305 first reads the electronic tag 1021ID on the current partition plate 102 and simultaneously sends a trigger signal to the industrial control system, linking the industrial camera 304 to complete the scallion image. After the visual algorithm calculates information such as the diameter of the white part of the scallion and the length of the whole plant and generates a grading result, the industrial control system uniquely binds and stores the grading result with the electronic tag 1021ID, completing the association between the identification mark of a single scallion and the grading information. The scallions with the bound grading information are transported sequentially to the intermediate grading and sorting units of each group by the conveyor belt. The second RFID reader 502 at the current workstation reads the electronic tag 1021ID on the passing separator 102 in real time and uploads the ID information to the industrial control system. The industrial control system retrieves the pre-grading result corresponding to the ID and compares it with the current workstation. The corresponding grading level is compared. If they match, a sorting command is issued to trigger the unloading mechanism 4 to unload. If they do not match, no action is triggered. The scallions continue to be conveyed to the next station with the separator 102. The scallions pass through all intermediate grading and sorting stations in sequence. The second RFID reader 502 at each station independently completes the reading of the electronic tag 1021 and the matching of the grading level. The electronic tag 1021ID is used as the material tracking carrier throughout the process until the scallions are sorted and discharged by the corresponding grading station or conveyed to the end of the conveyor belt 1 to enter the end grading and sorting unit, thereby improving the accuracy of scallion grading and sorting.

[0026] In this embodiment, as Figure 6 , Figure 7 and Figure 8As shown, the top of the baffle 2 has a discharge port 202, which corresponds to the position of the receiving cavity above the conveyor belt 1. The width of the discharge port 202 is slightly larger than the width of the receiving cavity. The discharge mechanism 4 includes a discharge port baffle 401 disposed inside the discharge port 202. The bottom end of the discharge port baffle 401 is rotatably connected to the baffle 2. A fixing rod 402 is fixedly connected to the outside of the discharge port baffle 401. The fixing rod 402 is welded and fixed to the discharge port baffle 401. A cylinder 403 is installed on the outer wall of the baffle 2 below the discharge port 2. The cylinder 403 is fixed on the outer wall of the baffle 2. The output end of the cylinder 403 and the end of the fixing rod 402 away from the discharge port baffle 401 are hinged to a hinge rod 404. The two ends of the hinge rod 404 are respectively hinged to the output end of the cylinder 403 and the fixing rod 402. The cylinder 403 is initially in an extended state. In this state, the discharge port baffle 401 is pushed by the hinge rod 404 and the fixed rod 402, so that the discharge port baffle 401 is closed inside the discharge port 202. Its inner wall is flush with the inner wall of the baffle 2, forming a continuous and complete lateral limiting surface. The scallions carrying the scallions can move smoothly along the conveyor belt 1. Scallions that are not in this position will not fall out from the side. When the scallion that is currently passing matches the grading position of this station, that is, when the second RFID reader 502 detects that the electronic tag 1021ID on the current separator 102 matches, the cylinder 403 retracts and pulls the hinge rod 404. The hinge rod 404 drives the fixed rod 402 to rotate outward around the bottom of the discharge port baffle 401. The maximum rotation angle of the discharge port baffle 401 can reach 90°, which fully opens the discharge port 202 and forms a lateral discharge channel. The scallions in the receiving cavity can then be discharged from the discharge port 202 to complete the grading and sorting work.

[0027] In this embodiment, a limiting block 405 is fixedly connected to the outer wall of the discharge port baffle 401. The limiting block 405 is welded and fixed to the discharge port baffle 401. Both ends of the limiting block 405 extend to the outside of the discharge port baffle 401. When the discharge port baffle 401 closes and seals the discharge port 202, the protruding parts at both ends of the limiting block 405 directly abut against the outer wall of the baffle 2, restricting the discharge port baffle 401 from continuing to rotate inward, thus preventing the discharge port baffle 401 from flipping into the inside of the conveyor belt 1 and ensuring the sealing effect of the discharge port baffle 401 on the discharge port 202.

[0028] In this embodiment, as Figure 7As shown, the discharge mechanism 4 also includes a discharge pipe 406 fixedly connected to the outer wall of the baffle 2 and located around the discharge port 202. The discharge pipe 406 is inclined, and a clearance groove is provided at the end of the discharge pipe 406 near the baffle 2 for the fixed rod 402 and the hinge rod 404 to move. The discharge pipe 406 surrounds the discharge port 202 and is arranged at an inclination to completely receive the green onions discharged from the discharge port 202. The green onions are guided to slide down the pipe by their own weight by the inclined slope and fall into the collection mechanism 6 below for centralized collection. This avoids the long strips of green onions from deflecting, bouncing, or falling outside the collection box when they are discharged laterally, ensuring that all materials are collected, maintaining the cleanliness of the work site, and eliminating the need for manual repeated picking up of scattered materials. The clearance groove on the discharge pipe provides sufficient space for the swing stroke of the fixed rod 402 and the hinge rod 404, avoiding jamming and scraping problems during the transmission process.

[0029] In this embodiment, as Figure 9 As shown, the positioning blowing mechanism 5 also includes a blowing nozzle 503 mounted on the mounting frame 501. The blowing direction of the blowing nozzle 503 is towards the discharge port 202. The blowing nozzle 503 is connected to the air supply equipment through an air pipe. After the discharge port baffle 401 is rotated open, the air supply equipment delivers gas to the blowing nozzle 503. The blowing nozzle 503 blows gas into the receiving cavity. The working air pressure of the blowing nozzle is 0.2-0.3MPa. It acts on the scallion in the receiving cavity, applying a uniform lateral thrust, pushing the scallion to overcome the surface friction of the conveyor belt 1, and moving it from the receiving cavity towards the discharge port 202. It passes through the opened discharge port 202 and enters the outer discharge pipe 406, completing the unloading of a single scallion.

[0030] In this embodiment, the preferred tilt angle of the conveyor belt 1 is 10°-15°, ensuring stable conveying posture. At this angle, the scallions will not slide down or fall over on their own. With the physical separation of the partition plate, each scallion remains close to the baffle plate, maintaining a uniform posture. This ensures consistent imaging position and stable dimensional measurement accuracy during visual inspection. The lateral weight of the scallions can offset some of the friction force on the belt surface. After the discharge port 202 is opened, it can be smoothly discharged with the help of low-pressure airflow. Compared with a horizontal conveyor belt, the blowing pressure can be reduced by about 30%, avoiding high-pressure airflow from scratching the white skin of the scallions. The conveyor belt 1 conveys at a uniform speed under normal conditions. When it is matched to the corresponding grade level, it briefly pauses to unload the material. After unloading, the conveying resumes.

[0031] In this embodiment, as Figure 1 , Figure 2 and Figure 10As shown, the receiving mechanism 6 of the intermediate grading and sorting unit is used to collect the scallion material discharged from the discharge pipe 406, and the receiving mechanism 6 of the tail-end grading and sorting unit is used to collect the scallion material discharged from the tail end of the conveyor belt 1. The receiving mechanism 6 includes a receiving base 601, and two placement seats 602 are provided on the top of the receiving base 601. A receiving box 606 is embedded in the top of the placement seat 602. A placement groove is opened on the top of the placement seat 602, and the receiving box 606 is placed in the placement groove of the placement seat 602. A screw groove is opened on the top of the receiving base 601 along the length direction, and a screw 603 is rotatably connected in the screw groove. A drive motor 605 is installed on one side, and the output end of the drive motor 605 is fixedly connected to one end of the lead screw 603. A threaded sleeve is fixedly connected to the bottom of the placement seat 602, which is placed in the lead screw groove and threadedly connected to the lead screw 603. The top of the receiving base 601 has guide grooves on both sides of the lead screw groove, and a guide rod 604 is fixedly connected in the guide groove. A guide sleeve is fixedly connected to the bottom of the placement seat 602, which is placed in the guide groove and slidably connected to the guide rod 604. One set of placement seats 602 and receiving box 606 constitutes one receiving station. The length of the receiving base 601 is used to accommodate three receiving stations. The three receiving stations are respectively for receiving... The material receiving station, the waiting transfer station, and the standby station are initially positioned with two placement seats 602 located at the receiving station and the standby station, respectively. The receiving box 606 is placed directly below the discharge end of the discharge pipe 406 or directly below the material drop point at the end of the conveyor belt 1. The scallions slide down from the discharge pipe 406 or fall naturally from the end of the conveyor belt 1 into the receiving box 606 at the current receiving station. Scallions of the corresponding grade are continuously collected and stored. When the receiving box 606 reaches a full state, the drive motor 605 starts and drives the lead screw 603 to rotate at a constant speed. The threaded sleeve drives the two placement seats 602 to move horizontally through the threaded transmission, and the full receiving box 606 is placed accordingly. The placement seat 602 is moved to the side waiting transfer station, and at the same time, the spare empty receiving box 606 is moved to the bottom of the discharge pipe 406 to take over the receiving operation. The entire equipment switching process does not require machine shutdown, and the sorting operation is continuous and uninterrupted. The operator can directly take out the full receiving box 606 from the side waiting transfer station and replace it with an empty receiving box 606, which is then embedded into the placement seat 602 to complete the replacement. The three-station base 601 is designed to provide an independent operating space for manual box changing. The box changing process does not interfere with the normal receiving station. The equipment continuously cycles through receiving, switching between full and empty boxes, and replenishing boxes, realizing non-stop sorting operations, improving work efficiency and the convenience of manual operation.

[0032] In practical implementation, the full state of the receiving bin 606 can be triggered by sorting count, time accumulation, or photoelectric detection. Sorting count trigger does not require additional detection sensors; it directly reuses the existing sorting action signals of the device, using the matching unloading command of the second RFID reader 502 and the magnetic switch signal of the cylinder 403 extending to the position as the counting basis. The high-speed counter module inside the PLC controller completes the quantity accumulation. Time accumulation trigger can be implemented using the timer module inside the PLC controller, without adding any external detection components. The fullness is determined by accumulating the effective sorting time of the equipment. Photoelectric detection trigger can be achieved by installing a through-beam photoelectric sensor at the rated full height position of each receiving bin 606. The sensor transmitter and receiver are respectively installed on the placement brackets on both sides of the receiving bin 606. The detection signal is connected to the digital input port of the PLC controller. Waterproof photoelectric sensors are preferred to adapt to the dusty and humid working conditions of the scallion sorting workshop.

[0033] In this embodiment, the automatic grading and sorting device for scallions based on machine vision is controlled by a PLC controller and an industrial computer. The industrial computer and the PLC controller achieve bidirectional data interaction through an industrial Ethernet. The industrial computer is electrically connected to the industrial camera 304, the first RFID reader 305, and the second RFID reader 502. The PLC controller is electrically connected to the conveyor belt 1, the supplementary light 306, the air supply source for the cylinder 403, the air supply equipment for the blowing nozzle 503, and the drive motor 605. The control program of the controller and the industrial control system of the industrial computer can be implemented by those skilled in the art through programming. Therefore, the control method and circuit connection will not be explained in detail in this invention.

[0034] Working principle: At the feeding end of conveyor belt 1, the operator places one scallion at a time into the independent receiving cavity formed by the adjacent partition plates 102 and the belt body. The inclined conveyor belt 1 transports the scallion material at a uniform speed. The root of the scallion abuts against the baffle 2 on the lower side of the conveyor belt 1. The baffle 2 provides lateral restraint, preventing the scallion from sliding outward. The partition plates 102, which are arranged at equal intervals, form a physical separation between the front and rear scallions. Together with the inclined belt body, they constrain the posture of the scallions, preventing them from rolling, sliding, or tangling and stacking during the transportation process. This ensures that each scallion maintains an independent and uniform placement posture and is continuously transported to the grading and testing mechanism. The scallions enter the closed inspection area of ​​the inspection box 301 along with the conveyor belt 1. The first RFID reader 305 first reads the electronic tag 1021ID on the current partition plate 102 and sends a trigger signal to the industrial control computer. The supplementary lights 306 on both sides of the industrial camera 304 are lit to provide uniform illumination for the inspection area. The industrial camera 304 takes a complete picture of the scallions directly below. The inspection box 301 isolates the interference of external natural light and ambient light to ensure that the lighting conditions are consistent for each scallion when it is photographed. Finally, it obtains a scallion appearance image with uniform proportions, clear outlines, and no perspective distortion. The vision algorithm of the industrial control computer processes the scallion image, extracts the overall outline of the scallion, calculates the length of the whole plant, locates the white part of the scallion and converts the diameter of the white part, and automatically determines the sorting grade of the scallion according to the preset grading threshold. The industrial control computer uniquely binds and stores the generated grading result with the electronic tag 1021ID through the first RFID reader 305, completing the identification mark and grading information association of a single scallion. Scallions bound with grading information pass sequentially through each intermediate grading and sorting unit on conveyor belt 1. The second RFID reader 502 at the current workstation reads the electronic tag 1021ID of the passing scallions in real time and uploads the ID information to the industrial control computer. The industrial control computer retrieves the pre-grading result bound to the ID and compares it with the grading level of the current workstation. If the level does not match, the discharge mechanism 4 remains closed, and the scallions continue to be conveyed to the next workstation with the separator 102. If the level matches, the industrial control computer sends a sorting command to the PLC controller. The PLC controller controls the conveyor belt 1 to stop conveying. Then, the PLC controller simultaneously controls two actions: first, the cylinder 403 of the discharge mechanism 4 retracts, pulling the fixed rod 402 through the hinge rod 404, causing the discharge port baffle 401 to rotate outward around the bottom end, fully opening the discharge port 202; second, the gas supply equipment works to deliver gas to... The blowing nozzle 503 sprays a directional airflow into the receiving cavity. The directional airflow applies a uniform lateral thrust to the scallions, pushing them to overcome surface friction and move them out of the discharge port 202 and into the outer discharge pipe 406. The discharge pipe 406 is tilted and guided, and the scallions slide down the pipe by their own weight, accurately falling into the receiving box 606 of the corresponding grade below, completing the sorting and collection of the scallions at that grade. After the preset blowing time ends, the cylinder 403 extends and resets, causing the discharge port baffle 401 to flip inward and close. The limiting blocks 405 abut against the outer wall of the baffle 2 at both ends to achieve precise limiting, preventing the discharge port baffle from flipping inward too much, waiting for the next group of materials to pass. The scallions pass through all intermediate grading and sorting stations in sequence. Each station independently completes label reading, grade matching and unloading actions. The entire process uses the electronic tag 1021ID as the material tracking carrier to achieve accurate grading. During the sorting process, each receiving mechanism 6 synchronously performs uninterrupted material receiving and automatic box changing to ensure continuous sorting. During normal operation, the receiving box 606 at the aligned discharge pipe 406 continuously receives the corresponding grade of scallions to complete material collection. When the current receiving box 606 reaches the full state, the PLC controller controls the drive motor 605 to start. The threaded sleeve drives the two placement seats 602 to move horizontally through the threaded transmission. The full receiving box 606 moves with the placement seat 602 to the side waiting transfer station. At the same time, the empty spare receiving box 606 moves to the bottom of the discharge pipe 406 to take over the material receiving operation. The entire equipment switching process does not require machine shutdown, and the sorting operation is continuous and uninterrupted. The operator can directly take out the full receiving box 606 at the side waiting transfer station and replace it with an empty receiving box 606, which is embedded into the placement seat 602 to complete the replacement. The three-station base provides an independent operating space for box changing. The box changing operation and normal material receiving do not interfere with each other. The equipment cycles through the material receiving, full box switching, and box replenishment process. The scallions that are not sorted out by all the intermediate grading and sorting units are continuously transported to the end of the discharge end by the conveyor belt 1. They fall naturally from the end of the conveyor belt 1 by their own weight and fall directly into the receiving box 606 of the end grading and sorting unit, thus completing the complete collection of all the scallions without any material residue or leakage.

[0035] The above embodiments are preferred implementations of the present invention. In addition, the present invention can be implemented in other ways. Any obvious substitutions without departing from the concept of the present technical solution are within the protection scope of the present invention.

Claims

1. An automatic grading and sorting device for scallions based on machine vision, characterized in that, include: Conveyor belt (1), the conveyor belt (1) is used to transport scallions, the conveyor belt (1) is inclined along the conveying direction, the bottom of the conveyor belt (1) is fixedly connected to a support frame (101), and a number of partition plates (102) are fixedly connected at equal intervals on the outer wall of the conveyor belt (1), and two adjacent partition plates (102) and the belt body form a receiving cavity for accommodating scallions; The grading and testing mechanism (3) includes a testing box (301) sleeved on the outside of the conveyor belt (1). Connecting legs (302) are fixedly connected to both sides of the bottom of the testing box (301). The connecting legs (302) are fixedly connected to the support frame (101). An installation plate (303) is fixedly connected to the top inside the testing box (301). The installation plate (303) is also inclined and has the same inclination angle as the conveyor belt (1). An industrial camera (304) is installed at the bottom of the installation plate (303). Baffle (2), the baffle (2) is arranged along the length of the conveyor belt (1) and is located at the lower end of the conveyor belt (1). The baffle (2) is also inclined and has the same inclination angle as the conveyor belt (1). The baffle (2) is fixedly connected to the support frame (101) by a fixing frame (201). The grading and sorting unit includes an intermediate grading and sorting unit and a tail-end grading and sorting unit. The tail-end grading and sorting unit is located at the discharge end of the conveyor belt (1). Multiple sets of intermediate grading and sorting units are located between the detection box (301) and the tail-end grading and sorting unit. The intermediate grading and sorting unit includes a discharge mechanism (4) on the baffle (2), a positioning blowing mechanism (5) on the conveyor belt (1), and a receiving mechanism (6). The tail-end grading and sorting unit includes a receiving mechanism (6).

2. The automatic grading and sorting device for scallions based on machine vision according to claim 1, characterized in that, The separator plate (102) is equipped with an electronic tag (1021) at the higher end of the conveyor belt (1), and the bottom of the mounting plate (303) is equipped with a first RFID reader (305) corresponding to the position of the electronic tag (1021).

3. The automatic grading and sorting device for scallions based on machine vision according to claim 2, characterized in that, The positioning blowing mechanism (5) includes a mounting frame (501) fixedly connected to the back of the support frame (101), and a second RFID reader (502) corresponding to the position of the electronic tag (1021) is installed at the top of the mounting frame (501).

4. The automatic grading and sorting device for scallions based on machine vision according to claim 3, characterized in that, The top of the baffle (2) is provided with a discharge port (202). The discharge mechanism (4) includes a discharge port baffle (401) disposed inside the discharge port (202). The bottom end of the discharge port baffle (401) is rotatably connected to the baffle (2). A fixing rod (402) is fixedly connected to the outside of the discharge port baffle (401). A cylinder (403) is installed on the outer side wall of the baffle (2) below the discharge port (202). A hinge rod (404) is hinged to the output end of the cylinder (403) and the end of the fixing rod (402) away from the discharge port baffle (401).

5. The automatic grading and sorting device for scallions based on machine vision according to claim 4, characterized in that, A limiting block (405) is fixedly connected to the outer wall of the discharge port baffle (401), and both ends of the limiting block (405) extend to the outside of the discharge port baffle (401).

6. The automatic grading and sorting device for scallions based on machine vision according to claim 5, characterized in that, The discharge mechanism (4) further includes a discharge pipe (406) fixedly connected to the outer wall of the baffle (2) and located around the discharge port (202). The discharge pipe (406) is inclined and has a clearance groove at one end near the baffle (2) for the fixed rod (402) and the hinge rod (404) to move.

7. The automatic grading and sorting device for scallions based on machine vision according to claim 4, characterized in that, The positioning blowing mechanism (5) also includes a blowing nozzle (503) mounted on the mounting frame (501), and the blowing direction of the blowing nozzle (503) is towards the outlet (202).

8. The automatic grading and sorting device for scallions based on machine vision according to claim 1, characterized in that, The bottom of the mounting plate (303) is equipped with fill lights (306) on both sides of the industrial camera (304).

9. The automatic grading and sorting device for scallions based on machine vision according to claim 6, characterized in that, The receiving mechanism (6) of the intermediate grading and sorting unit is used to collect the scallion material discharged from the discharge pipe (406), and the receiving mechanism (6) of the tail-end grading and sorting unit is used to collect the scallion material discharged from the tail end of the conveyor belt (1). The receiving mechanism (6) includes a receiving base (601), and two placement seats (602) are provided on the top of the receiving base (601). A receiving box (606) is embedded in the top of the placement seat (602). A screw groove is opened on the top of the receiving base (601) along the length direction, and a screw (606) is rotatably connected in the screw groove. 03), a drive motor (605) is installed on one side of the receiving base (601). The output end of the drive motor (605) is fixedly connected to one end of the lead screw (603). A threaded sleeve is fixedly connected to the bottom of the placement seat (602), which is placed in the lead screw groove and threadedly connected to the lead screw (603). Guide grooves are opened on both sides of the top of the receiving base (601) at the lead screw groove. A guide rod (604) is fixedly connected in the guide groove. A guide sleeve is fixedly connected to the bottom of the placement seat (602), which is placed in the guide groove and slidably connected to the guide rod (604).

10. The automatic grading and sorting device for scallions based on machine vision according to claim 9, characterized in that, A set of the placement seat (602) and the receiving box (606) constitutes a receiving station, and the length of the receiving base (601) is used to accommodate three receiving stations.

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