A dynamic weighing system based on machine vision

Abstract

The application relates to the field of article weighing detection, in particular to a dynamic weighing system based on machine vision. The dynamic weighing system based on machine vision comprises a rack, a weighing device, a feeding conveying device and a discharging conveying device. The weighing device comprises a weighing table and a display module. The feeding conveying device conveys materials to the weighing device, and the discharging conveying device carries the materials away from the weighing device. The dynamic weighing system based on machine vision further comprises a material pushing device and a weighing visual recognition device. The material pushing device pushes the materials from the feeding conveying device to the weighing table and pushes the materials from the weighing table to the discharging conveying device after the weighing is completed. The weighing visual recognition device recognizes the weight information displayed by the display module. The weight information of the weighing device is recognized by the weighing visual recognition device, and the weighing device does not need to be modified to be connected with a signal line. The accuracy of the weighing device is high.

Description

Technical Field

[0001] This invention relates to the field of weighing and inspection of goods, and in particular to a dynamic weighing system based on machine vision. Background Technology

[0002] The integration of microprocessors and load cells revolutionized the weighing field. Since then, microprocessors have been increasingly used in weighing, especially in dynamic weighing, largely replacing the previously complex computing systems. The continuous development of microelectronics technology and the emergence of large-scale and very large-scale integrated circuits have enabled the integration of weighing and process control functions into a single electronic unit. By the 1980s, electronic weighing instruments had permeated all areas, from micro-weighing to large-scale professional weighing, with thousands of specifications and varieties available. Static accuracy is generally above 0.1%, and dynamic accuracy is generally between 1% and 0.2%. During production line design, customers with high weighing accuracy requirements typically require that the internal structure of existing weighing devices, including external signal lines, not be altered to avoid affecting accuracy. Therefore, production lines with high-precision weighing devices usually require static measurement methods. Static measurement typically requires intelligent robotic arms for gripping or manual loading and unloading, which is costly.

[0003] Chinese utility model patent CN209601330U discloses an online data exchange automatic warehousing shared production line. This production line uses a visual barcode scanner to scan and identify packaged products to confirm their information. Then, an automatic weighing device weighs the product, and a networked industrial control computer compares the weight corresponding to the product's information with the actual weight measured by the automatic weighing device to determine if the product's weight is acceptable. This production line automates product conveying, barcode scanning, and weighing, improving work efficiency and achieving dynamic weighing. However, such production lines typically require modification of the weighing device's external signal line to enable rapid transmission of weight information to the production line's processing system. This modification significantly impacts the accuracy of the weighing device, leading to lower accuracy and potentially misjudging the actual weight, thus affecting the determination of product weight compliance. Summary of the Invention

[0004] The purpose of this invention is to provide a dynamic weighing system based on machine vision to solve the problem of low accuracy of weighing devices in existing production lines due to the need to modify the weighing devices with external signal lines.

[0005] The technical solution of the machine vision-based dynamic weighing system of the present invention is as follows:

[0006] The machine vision-based dynamic weighing system includes a frame, a weighing device mounted on the frame for weighing materials, a feeding conveyor, and a discharging conveyor, all mounted on the frame. The weighing device includes a weighing platform and a display module. The weighing platform is used to weigh the materials, and the display module displays the weight information of the materials. The feeding conveyor is located upstream of the weighing device and is used to transport materials from front to back onto the weighing device. The discharging conveyor is located downstream of the weighing device and is used to transport materials from front to back away from the weighing device. The machine vision-based dynamic weighing system also includes a material pushing device and a weighing vision recognition device. The material pushing device pushes the materials from the feeding conveyor onto the weighing platform and, after weighing, pushes the materials from the weighing platform to the discharging conveyor. The weighing vision recognition device recognizes the weight information displayed on the display module. The machine vision-based dynamic weighing system also includes a controller connected to the material pushing device to control its operation.

[0007] Beneficial effects: The feeding conveyor of the machine vision-based dynamic weighing system transports materials from front to back to the weighing platform of the weighing device. Under the action of the material pushing device, the materials are pushed onto the weighing platform for weighing. After weighing, the material pushing device pushes the materials to the unloading conveyor, which continues to transport the materials backward. When the weighing device weighs the materials, the weighing vision recognition device of the machine vision-based dynamic weighing system can identify the weight information of the materials displayed on the display module. The weight information of the weighing device of the machine vision-based dynamic weighing system of this invention is obtained through the weighing vision recognition device. Therefore, it is not necessary to modify the external signal line of the weighing device, and the accuracy of the weighing device will not be affected by the modification of the weighing device. The accuracy of the weighing device is high.

[0008] Furthermore, the weighing visual recognition device includes a weighing camera for taking pictures of the display module, a weighing photography light source for providing light to the symmetrical weighing camera, a weighing camera adjustment frame, and a light source adjustment frame. The weighing camera adjustment frame is used to adjust the shooting angle of the weighing camera, and the light source adjustment frame is used to adjust the angle of the light source provided by the symmetrical weighing camera to the weighing photography light source.

[0009] Beneficial effects: The weighing camera is used to take pictures of the display module, and the weighing camera light source is used to provide light for the camera to take pictures. By adjusting the light source adjustment frame and the weighing camera adjustment frame, the clarity of the pictures taken by the weighing camera can be effectively improved.

[0010] Furthermore, the weighing camera adjustment frame includes a left-right moving rod and a right-up moving rod. The left-right moving rod is guided and mounted on the frame, and the right-up moving rod is guided and mounted on the left-right moving rod. The weighing camera is rotatably mounted on the right-up moving rod. The light source adjustment frame includes a left-right moving rod and a right-up moving rod. The left-right moving rod is guided and mounted on the frame, and the right-up moving rod is guided and mounted on the left-right moving rod. The light source for weighing and taking pictures is rotatably mounted on the right-up moving rod.

[0011] Beneficial effects: The weighing camera adjustment frame and light source adjustment frame adopt this structure, which is simple and allows for flexible adjustment of the shooting angle of the weighing camera and the light source angle of the weighing photography light source, making adjustment more convenient.

[0012] Furthermore, the weighing platform includes at least two legs, which are fixed to the frame.

[0013] Beneficial effects: The weighing platform is fixed to the frame by the support legs, which makes the weighing platform less prone to shaking and the weighing results more accurate.

[0014] Furthermore, the material pushing device includes a ring chain, a ring chain drive wheel that drives the ring chain to move, and at least two push rods. The ring chain is connected to the push rods, and each push rod extends along the axial direction of the ring chain drive wheel. Each push rod moves with the ring chain to push the material, and each push rod is spaced apart along the extension direction of the ring chain.

[0015] Beneficial effects: The material pushing device pushes materials by driving push rods through a ring chain. The speed of pushing materials can be controlled by controlling the movement speed of the ring chain, making it easier to control the overall conveying speed of materials.

[0016] Furthermore, the push rod has a material separation position during the process of pushing the material onto the weighing platform. After pushing the material onto the weighing platform, the push rod retracts to the material separation position so that the push rod separates from the material.

[0017] Beneficial effect: After the push rod pushes the material to the weighing platform, it separates from the material, making the weight of the material measured by the weighing platform more accurate.

[0018] Furthermore, the machine vision-based dynamic weighing system also includes a model vision recognition device located upstream of the weighing platform. The model vision recognition device is used to identify the model of the material. During the movement, the push rod has a push rod falling position upstream of the model vision recognition device. The push rod falling position is located at the corner of the ring chain. After the push rod falls to the push rod falling position with the ring chain, it moves from the push rod falling position along with the material conveyed by the feeding conveyor to the weighing platform and pushes the material onto the weighing platform.

[0019] Beneficial effects: Compared to setting the push rod's drop position downstream of the model visual recognition device, placing the push rod's drop position upstream of the visual signal recognition device eliminates the need for additional material waiting space, resulting in a compact layout between the model visual recognition device and the material pushing device, and occupying less space.

[0020] Furthermore, the feeding and conveying device includes multiple spaced conveying rollers, which rotate to convey materials. The model visual recognition device includes a push rod for lifting materials. The push rod moves upward from the interval between adjacent conveying rollers to lift the materials on the conveying rollers. The model visual recognition device includes a visual recognition module located on the right side of the feeding and conveying device and a pushing mechanism for pushing the materials on the push rod toward the visual recognition module. The visual recognition module is used to identify the model of the materials. The model visual recognition device also includes a positioning detection sensor for detecting the position of the materials. At least two positioning detection sensors are arranged in the material conveying direction. After at least two positioning detection sensors detect that the materials have been pushed into place by the pushing mechanism, the controller controls the pushing mechanism to stop pushing the materials.

[0021] Beneficial effects: After the material is lifted by the push rod, the pushing mechanism pushes the material toward the vision recognition module. During the process of pushing the material, the pushing mechanism has a righting effect on the material, so that the material has a uniform posture after being pushed by the pushing mechanism. The righting of the material not only facilitates the subsequent pushing of the push rod, but also facilitates the vision recognition module to identify the material's model, making the identification faster and more accurate.

[0022] Furthermore, the machine vision-based dynamic weighing system also includes a model vision recognition device located upstream of the weighing platform. The feeding and conveying device includes multiple spaced conveying rollers that rotate to convey materials. The model vision recognition device includes a push rod for lifting materials. The push rod moves upward from the interval between adjacent conveying rollers to lift the materials on the conveying rollers. The model vision recognition device includes a vision recognition module located on the right side of the feeding and conveying device and a pushing mechanism for pushing the materials on the push rod toward the vision recognition module. The vision recognition module is used to identify the model of the materials. The model vision recognition device also includes a positioning detection sensor for detecting the position of the materials. At least two positioning detection sensors are arranged in the material conveying direction. After at least two positioning detection sensors detect that the materials have been pushed into place by the pushing mechanism, the controller controls the pushing mechanism to stop pushing the materials.

[0023] Beneficial effects: After the material is lifted by the push rod, the pushing mechanism pushes the material toward the vision recognition module. During the process of pushing the material, the pushing mechanism has a righting effect on the material, so that the material has a uniform posture after being pushed by the pushing mechanism. The righting of the material makes it easier for the vision recognition module to identify the model of the material, and the identification is faster and more accurate.

[0024] Furthermore, the machine vision-based dynamic weighing system also includes a material blocking mechanism, which is used to prevent subsequent materials from moving onto the weighing platform when the platform is weighing the material.

[0025] Beneficial effects: The material blocking mechanism enables the machine vision-based dynamic weighing system to weigh materials in an orderly manner, avoiding interference from subsequently conveyed materials to the material being weighed. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the appearance of the machine vision-based dynamic weighing system in Embodiment 1 of the present invention.

[0027] Figure 2 This is a schematic diagram of the structure of the machine vision-based dynamic weighing system after the protective cover is hidden in Embodiment 1 of the present invention.

[0028] Figure 3 This is a partial structural schematic diagram of the dynamic weighing system based on machine vision in Embodiment 1 of the present invention.

[0029] Figure 4 This is a schematic diagram showing the connection of the light source for taking model photos, the model camera, and the model camera adjustment bracket in the model visual recognition device of Embodiment 1 of the dynamic weighing system based on machine vision of the present invention.

[0030] Figure 5 This is a schematic diagram of the material pushing device in Embodiment 1 of the machine vision-based dynamic weighing system of the present invention;

[0031] Figure 6 This is a schematic diagram of the lifting device in Embodiment 1 of the machine vision-based dynamic weighing system of the present invention;

[0032] Figure 7 This is a schematic diagram of the weighing device in Embodiment 1 of the machine vision-based dynamic weighing system of the present invention;

[0033] Figure 8 This is a schematic diagram of the rejection device in Embodiment 1 of the machine vision-based dynamic weighing system of the present invention.

[0034] Explanation of reference numerals in the attached drawings: 1. Frame; 2. Weighing device; 201. Weighing platform; 2011. Support leg; 202. Display module; 3. Feeding conveyor; 4. Discharging conveyor; 5. Model visual recognition device; 6. Conveyor roller mounting plate; 7. Conveyor roller; 8. Visual recognition module; 9. Model camera; 10. Model camera adjustment frame; 101. Base plate; 102. Guide rod; 103. Left and right adjustment rod; 104. Left and right adjustment block; 105. Up and down adjustment rod; 106. Up and down adjustment block; 11. Light source for model photography; 12. Top rod; 13. Pushing mechanism; 131. Push plate; 1311. Top rod through groove; 132. Push plate drive cylinder; 14. Alignment detection sensor; 15. Material pushing device; 151. Push rod; 152. Circular chain; 153. Circular chain drive wheel; 154. Material pushing frame; 155. 156. Sprocket drive motor; 157. Transmission chain; 158. Transmission sprocket; 159. Drive shaft; 16. Material blocking mechanism; 161. First material blocking plate; 162. Second material blocking plate; 17. First position sensor; 18. Second position sensor; 19. Weighing vision recognition device; 20. Weighing camera; 21. Weighing and photographing light source; 22. Light source adjustment frame; 221. Light source left and right movement rod; 222. Light source up and down movement rod; 23. Weighing camera adjustment frame; 231. Camera left and right movement rod; 232. Camera up and down movement rod; 24. Rejection device; 241. Rejection plate; 242. Rejection plate drive cylinder; 243. Moving plate; 244. Connecting rod; 25. Third position sensor; 26. Protective cover; 27. Lifting device mounting base; 28. Movable rod; 29. ​​Push rod drive cylinder; 30. Push plate; 31. Push rod fixing rod. Detailed Implementation

[0035] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention; that is, the described embodiments are merely some embodiments of the invention, not all embodiments. The components of the embodiments of the invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0036] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0037] It should be noted that, in specific embodiments of the present invention, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply such an actual relationship or order between these entities or operations. Furthermore, terms such as "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, the use of phrases such as "comprising a…" to define an element does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0038] In the description of this invention, unless otherwise explicitly specified and limited, terms such as "installation," "connection," and "linkage" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium, or they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0039] In the description of this invention, unless otherwise explicitly specified and limited, the term "provided with" should be interpreted broadly. For example, the object "provided with" can be a part of the body, or it can be separately arranged from the body and connected to the body. This connection can be a detachable connection or a non-detachable connection. Those skilled in the art can understand the specific meaning of the above terms in this invention through specific circumstances.

[0040] The present invention will be further described in detail below with reference to the embodiments.

[0041] Embodiment 1 of the machine vision-based dynamic weighing system provided in this invention:

[0042] like Figures 1 to 8As shown, the machine vision-based dynamic weighing system includes a frame 1, a weighing device 2 for weighing materials mounted on the frame 1, a feeding conveyor 3, and a discharging conveyor 4. The weighing device 2 includes a weighing platform 201 and a display module 202. The weighing platform 201 is used to weigh the materials and is located between the feeding conveyor 3 and the discharging conveyor 4. The display module 202 is used to display the weight information of the materials. Both the feeding conveyor 3 and the discharging conveyor 4 are mounted on the frame 1. The feeding conveyor 3 is used to convey materials from front to back onto the weighing platform 201, and the discharging conveyor 4 is used to transport materials from front to back away from the weighing platform 201. In addition, a model vision recognition device 5 is provided upstream of the weighing platform 201. The model vision recognition device 5 can identify the model of the material to confirm the standard weight of the material. The machine vision-based dynamic weighing system has a controller. The controller can compare and analyze the standard weight data of the material with the actual weight data of the material measured by the weighing platform 201 to determine whether the weight of the material meets the standard. The judgment standard can be set according to actual needs, for example, the difference between the actual weight of the material and the standard weight does not exceed 0.1%.

[0043] It should be noted that the coordinated movement of each motion mechanism in the machine vision-based dynamic weighing system is also controlled by the controller.

[0044] In this embodiment, both the feeding conveying device 3 and the unloading conveying device 4 include two conveying roller mounting plates 6 arranged at left and right intervals. The conveying roller mounting plates 6 extend forward and backward, and multiple conveying rollers 7 are arranged at front and back intervals on the two conveying roller mounting plates 6. The conveying rollers 7 are driven by a motor to rotate so as to convey materials.

[0045] The model visual recognition device 5 includes a visual recognition module 8 for identifying material models. The visual recognition module 8 includes a model camera 9 for taking pictures of the material and a model recognition processor for processing the material pictures and determining the material model. After determining the material model, the model recognition processor transmits the relevant material information to the controller. The model camera 9 is mounted on a model camera adjustment frame 10. Specifically, the model camera adjustment frame 10 includes a base plate 101 fixed to the frame 1 and two guide rods 102 fixed to the base plate 101 with a front-to-back spacing. The two guide rods 102 extend left and right, and left and right adjustment rods 103 are provided on the guide rods 102. The left and right adjustment rods 103 are slidably mounted on the guide rods 102 by left and right adjustment blocks 104. The left-right adjustment lever 103 is equipped with a right-right adjustment lever 105. The right-right adjustment lever 105 is slidably mounted on the left-right adjustment lever 103 via a right-right adjustment block 106. The camera 9 is rotatably mounted on the right-right adjustment lever 105. The camera 9 can be adjusted up and down and left and right via the right-right adjustment lever 105 and the left-right adjustment lever 103. Furthermore, the camera 9 can also be rotated on the right-right adjustment lever 105. In addition, the camera adjustment bracket 10 is also equipped with a camera light source 11 to provide light for the camera 9. The camera light source 11 can also be adjusted up and down, left and right, and rotated. The structure for adjusting the camera light source 11 is the same as the structure for adjusting the camera 9, and will not be described in detail here. By coordinating the adjustment of the camera light source 11 and the camera 9, the clarity of the photos taken by the camera 9 can be effectively improved, which is beneficial for the model recognition processor to process and recognize the photos.

[0046] The model vision recognition device 5 also includes a lifting device for lifting materials, a pushing mechanism 13 for pushing materials toward the vision recognition module 8, and a positioning detection sensor 14 for detecting the position of materials.

[0047] The lifting device is located below the feeding and conveying device 3. The lifting device includes a lifting rod 12, a lifting device mounting base 27 fixed to the frame 1, movable rods 28 movably mounted on the lifting device mounting base 27, and a lifting rod drive cylinder 29 fixed to the lifting device mounting base 27. Four movable rods 28 are provided, and the top of each movable rod 28 is connected to the top of the piston rod of the lifting rod drive cylinder 29 on the same push plate 30. The push plate 30 is connected to the lifting rod 12 via a lifting rod fixing rod 31. When the piston rod of the lifting rod drive cylinder 29 extends or retracts, it drives the push plate 30 to move up and down. The up-and-down movement of the push plate 30 drives the lifting rod 12 to move up and down. When the lifting rod 12 moves upward, it can lift the material. Multiple push rods 12 are provided and spaced apart on the push plate 30. The push rods 12 move upward from the intervals of adjacent conveying rollers 7 of the feeding conveying device 3 to lift the material on the conveying rollers 7. In this embodiment, the pushing mechanism 13 includes a push plate 131 and a push plate driving cylinder 132 that drives the push plate 131 to move left and right. The push plate 131 is provided with a push rod passage groove 1311. When the push plate 131 pushes the material towards the vision recognition module 8 from left to right, the push rods 12 pass through the push rod passage groove 1311 to avoid interference between the push plate 131 and the push rods 12. In this embodiment, the push plate 131 is driven by the push plate driving cylinder 132, and the push rods 12 are driven by the push rod driving cylinder 29. In other embodiments, the push plate and the push rods can also be driven by a screw and nut mechanism, a hydraulic cylinder, or a linear motor.

[0048] In this embodiment, three positioning detection sensors 14 are provided. These three sensors are positioned on the right-side conveyor roller mounting plate 6 of the feeding conveyor device 3, spaced apart. The material moves from left to right towards the vision recognition module 8 under the push of the push plate 131. When at least two positioning detection sensors 14 detect that the material has been pushed into position by the push plate 131, the controller controls the push plate drive cylinder 132 to stop the push plate 131 from pushing the material and return the push plate 131 to its starting position. After the material is lifted by the push rod 12, the pushing mechanism 13 pushes the material towards the vision recognition module 8. During the pushing process, the pushing mechanism 13 has a straightening effect on the material, ensuring that the material has a uniform posture after being pushed by the pushing mechanism 13. This facilitates the vision recognition module 8 in detecting the material's type, making identification faster and more accurate.

[0049] To facilitate the transport of materials to the weighing platform 201 and to enable the materials to be weighed sequentially, the machine vision-based dynamic weighing system also includes a material pushing device 15 and a material blocking mechanism 16.

[0050] The material blocking mechanism 16 includes a first baffle plate 161 and a second baffle plate 162. The first baffle plate 161 is located upstream of the second baffle plate 162. Additionally, a first positioning sensor 17 and a second positioning sensor 18 are provided on the conveyor roller mounting plate 6 on the left side of the feeding conveyor device 3. The first positioning sensor 17 corresponds to the first baffle plate 161, and the second positioning sensor 18 corresponds to the second baffle plate 162. When material is conveyed to the position of the first positioning sensor 17, the first positioning sensor 17 transmits a positioning signal to the controller. If the second positioning sensor 18 detects material at its position (i.e., material is undergoing model identification), the controller will control the first baffle plate 161 to block the material. If the second positioning sensor 18 does not detect material at its position (i.e., no material is undergoing model identification), the first baffle plate 161 remains inactive, and the material continues to be conveyed backward. When the material is conveyed to the position of the second positioning sensor 18, the second positioning sensor 18 transmits a positioning signal to the controller. After receiving the signal from the second positioning sensor 18, the controller controls the second baffle 162 to block the material. Then, the controller controls the push rod 12 to lift the material, and then the pushing mechanism 13 pushes the material towards the model vision recognition device 5 for model recognition. After the model recognition is completed, the controller controls the push rod 12 to retract and the second baffle 162 to no longer block the material, so that the material can continue to be conveyed for weighing.

[0051] Both the first baffle plate 161 and the second baffle plate 162 extend from the intervals between adjacent conveying rollers 7 of the feeding conveyor device 3 to block the material. In this embodiment, both the first baffle plate 161 and the second baffle plate 162 are driven by cylinders. When the piston rod of the cylinder extends, it can drive the first baffle plate 161 and the second baffle plate 162 to extend, thereby blocking the material. When the piston rod of the cylinder retracts, it can drive the first baffle plate 161 and the second baffle plate 162 to retract, allowing the material to pass smoothly. In other embodiments, the first baffle plate and the second baffle plate can also be driven by a lead screw and nut mechanism, a hydraulic cylinder, or a linear motor.

[0052] The material pushing device 15 includes a material pushing frame 154, push rods 151, annular chains 152, and annular chain drive wheels 153 that drive the annular chains 152. Two annular chains 152 are symmetrically arranged on the material pushing frame 154. Connecting pieces are provided on the annular chains 152. The push rods 151 extend axially along the annular chain drive wheels 153, and both ends of the push rods 151 are fixedly connected to one of the annular chains 152 via connecting pieces. In this embodiment, four push rods 151 are provided, spaced apart along the extension direction of the annular chains 152. Each push rod 151 moves with the annular chains 152 to push the material. The material pushing device 15 pushes the material through the push rods 151 and cooperates with the loading conveyor 3 and unloading conveyor 4 to ensure that the material can be smoothly conveyed to and removed from the weighing platform 201.

[0053] In addition, a drive mechanism for rotating the annular chain drive wheel 153 is also installed on the material pusher 154. The drive mechanism includes a sprocket drive motor 155, a transmission chain 156 driven by the sprocket drive motor 155, and a transmission sprocket 157. The transmission sprocket 157 is connected to the annular chain drive wheel 153 via a drive shaft 158. When the sprocket drive motor 155 rotates, the transmission chain 156 drives the transmission sprocket 157 to move, which in turn drives the drive shaft 158 ​​to rotate. The rotating drive shaft 158 ​​drives the annular chain drive wheel 153 connected to it to rotate, and the annular chain drive wheel 153 then drives the annular chain 152 to rotate, ultimately realizing the movement of the push rod 151.

[0054] It is particularly important to note that the push rod 151 has a material separation position during the process of pushing the material onto the weighing platform 201. After pushing the material onto the weighing platform 201, the push rod 151 retracts to the material separation position to separate itself from the material. This separation after the push rod 151 pushes the material onto the weighing platform 201 makes the weight measured by the weighing platform 201 more accurate. Furthermore, during its movement, the push rod 151 has a push rod falling position upstream of the model visual recognition device 5. The push rod falling position is located at the corner of the annular chain 152. After falling to the push rod falling position with the annular chain 152, the push rod 151 moves from the push rod falling position along with the material conveyed by the feeding conveyor 3 to the weighing platform 201 and pushes the material onto the weighing platform 201. Compared to setting the push rod's drop position downstream of the model visual recognition device 5, placing the push rod's drop position upstream of the model visual recognition device 5 eliminates the need for additional material waiting space, resulting in a compact layout between the model visual recognition device 5 and the material pushing device 15, and reducing the space required.

[0055] The machine vision-based dynamic weighing system also includes a weighing vision recognition device 19. The weighing vision recognition device 19 includes a weighing camera 20 for taking pictures of the display module 202 and a weight recognition processor for processing the pictures to identify the weight of the material. The weighing vision recognition device 19 also includes a weighing photography light source 21, a light source adjustment frame 22, and a weighing photography camera adjustment frame 23. The weighing photography camera adjustment frame 23 is used to adjust the shooting angle of the weighing photography camera 20, and the light source adjustment frame 22 is used to adjust the angle of the light source provided by the weighing photography light source 21 to the light source provided by the weighing photography camera 20. Specifically, the weighing camera adjustment frame 23 includes a left-right moving rod 231 and a right-down moving rod 232. The left-right moving rod 231 is guided left and right and mounted on the frame 1, while the right-down moving rod 232 is guided up and down and mounted on the left-right moving rod 231. The weighing camera 20 is rotatably mounted on the right-down moving rod 232. The light source adjustment frame 22 includes a left-right moving rod 221 and a right-down moving rod 222. The left-right moving rod 221 is guided left and right and mounted on the frame 1, while the right-down moving rod 222 is guided up and down and mounted on the left-right moving rod 221. The weighing and photographing light source 21 is rotatably mounted on the right-down moving rod 222. Adjusting the light source adjustment frame 22 and the weighing camera adjustment frame 23 effectively improves the clarity of the photos taken by the weighing camera 20. After recognizing the weight of the material, the weight recognition processor transmits the relevant material information to the controller.

[0056] The machine vision-based dynamic weighing system also includes a rejection device 24. The rejection device 24 includes a rejection plate 241 mounted on the feeding conveyor 4 and a rejection plate drive cylinder 242 that drives the rejection plate 241 to move from right to left. The piston rod of the rejection plate drive cylinder 242 is fixed to a moving plate 243. The rejection plate 241 is connected to the moving plate 243 via a connecting rod 244. When the piston rod of the rejection plate drive cylinder 242 extends or retracts, it drives the moving plate 243 to move left and right, thereby driving the rejection plate 241 to move left and right. Furthermore, a third positioning sensor 25 is provided on the conveyor roller mounting plate 6 on the right side of the feeding conveyor 4. When the third positioning sensor 25 detects material, the controller controls the rejection plate 241 based on the weight judgment result of the material. When the material is qualified, the piston rod of the rejection plate drive cylinder 242 remains in the retracted state, and the material is conveyed to the next station by the feeding conveyor 4. When the material is unqualified, the controller controls the piston rod of the rejection plate drive cylinder 242 to extend, and the rejection plate 241 pushes the material to the NG area from right to left (the NG area is the material unqualified area).

[0057] In this embodiment, the weighing platform 201 includes four support legs 2011, which are fixed to the frame 1. The support legs prevent the weighing platform 201 from wobbling, resulting in more accurate weighing results.

[0058] In this embodiment, the machine vision-based dynamic weighing system also includes a protective cover 26, which is used for the personal safety protection of the staff.

[0059] The workflow of the machine vision-based dynamic weighing system of the present invention is as follows:

[0060] When the material is conveyed from front to back to the position of the first positioning sensor 17 by the feeding conveyor 3, according to the detection result of the second positioning sensor 18, if there is material at the second positioning sensor 18, the controller controls the first baffle plate 161 to extend and block the material; if there is no material at the second positioning sensor 18, the controller controls the first baffle plate 161 to remain retracted, and the material continues to be conveyed backward. When the material is conveyed to the position of the second positioning sensor 18, the controller controls the second baffle plate 162 to extend and block the material, the push rod 12 extends and lifts the material, and then the push plate 131 pushes the material towards the model visual recognition device 5. The model visual recognition device 5 identifies the model of the material and transmits the model information of the material to the controller. Under the joint action of the push rod 151 of the material pushing device 15 and the feeding conveyor 3, the material is conveyed to the weighing platform 201. The weighing platform 201 weighs the material, and the weighing visual recognition device 19 takes a picture of the display module 202 and transmits the actual weight information of the material to the controller. Under the push of the push rod 151 of the material pushing device 15, the material is conveyed to the unloading conveyor 4. When the third positioning sensor 25 detects the material, the controller controls the rejection plate 241 according to the weight judgment result of the material. When the material weight is qualified, the piston rod of the rejection plate drive cylinder 242 remains in the retracted state, and the material is conveyed to the next station by the unloading conveyor 4. When the material weight is unqualified, the controller controls the piston rod of the rejection plate drive cylinder 242 to extend, and the rejection plate 241 pushes the material to the NG area from right to left.

[0061] In Embodiment 2 of the dynamic weighing system based on machine vision of the present invention, the difference from Embodiment 1 is that the light source for weighing and taking pictures of the weighing visual recognition device is fixedly mounted on the light source mounting bracket, and the weighing and taking pictures camera is mounted on the weighing and taking pictures camera adjustment bracket. Both the light source for weighing and taking pictures and the weighing and taking pictures camera are fixedly mounted and cannot be adjusted.

[0062] In Embodiment 3 of the dynamic weighing system based on machine vision of the present invention, unlike Embodiment 1, the weighing platform is directly welded and fixed to the frame, or in other embodiments, the weighing platform is placed on the frame.

[0063] Embodiment 4 of the machine vision-based dynamic weighing system of the present invention differs from Embodiment 1 in that the weighing platform includes two legs, which are located diagonally opposite each other. Alternatively, in other embodiments, the weighing platform includes three, five, six, or more legs.

[0064] Embodiment 5 of the machine vision-based dynamic weighing system of the present invention differs from Embodiment 1 in that the material pushing device includes a material driving cylinder, which pushes the material through the extension and retraction of the piston rod of the material pushing cylinder. Alternatively, in other embodiments, the material pushing cylinder can be replaced with a material driving hydraulic cylinder, a linear motor, etc.

[0065] In Embodiment 6 of the dynamic weighing system based on machine vision of the present invention, unlike Embodiment 1, the push rod does not have a material separation position during the process of pushing the material onto the weighing platform, and the push rod remains in contact with the material after pushing the material onto the weighing platform.

[0066] The seventh embodiment of the dynamic weighing system based on machine vision of the present invention differs from the first embodiment in that the push rod has a push rod falling position downstream of the model vision recognition device during the movement process. The length of the material pusher in the material conveying direction in this embodiment is shorter than the length of the material pusher in the material conveying direction in the first embodiment.

[0067] The 8th embodiment of the dynamic weighing system based on machine vision of the present invention differs from the 1st embodiment in that the model vision recognition device does not include a pushing mechanism. After the top rod lifts the material, the vision recognition module directly identifies the model of the material.

[0068] The embodiment 9 of the dynamic weighing system based on machine vision of the present invention differs from embodiment 1 in that both the loading and unloading conveying devices include conveyor belts, and the loading and unloading conveying devices transport materials through the conveyor belts.

[0069] The embodiment 10 of the dynamic weighing system based on machine vision of the present invention differs from embodiment 1 in that it does not have a material blocking mechanism. The feeding and conveying device adopts a step-type conveying. When the material is conveyed to the position of the first or second position sensor, the controller controls the feeding and conveying device to stop conveying so that the material stops in place. When the material needs to be conveyed, the controller controls the feeding and conveying device to convey the material again.

[0070] The embodiment 11 of the dynamic weighing system based on machine vision of the present invention differs from embodiment 1 in that the dynamic weighing system based on machine vision in this embodiment transports materials of a single type. Therefore, no type visual recognition device is set up upstream of the weighing platform, and the materials are directly transported to the weighing platform via the feeding conveyor.

[0071] The above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. The scope of patent protection of the present invention shall be determined by the claims. Similarly, any equivalent structural changes made based on the description and drawings of the present invention shall also be included within the scope of protection of the present invention.

Claims

1. A dynamic weighing system based on machine vision, characterized in that, The system includes a frame (1), a weighing device (2) mounted on the frame (1) for weighing materials, a feeding conveyor (3) mounted on the frame (1), and a discharging conveyor (4). The weighing device (2) includes a weighing platform (201) and a display module (202). The weighing platform (201) is used to weigh materials, and the display module (202) is used to display the weight information of the materials. The feeding conveyor (3) is located upstream of the weighing device (2) and is used to transport materials from front to back to the weighing device (2). The discharging conveyor (4) is located downstream of the weighing device (2) and is used to transport materials from front to back away from the weighing device (2). The machine vision-based dynamic weighing system also includes a material pushing device (15) and a weighing vision recognition device (19). The material pushing device (15) includes a fixed... The machine includes a material pusher on the frame, an annular chain (152) arranged on the material pusher, an annular chain drive wheel (153) that drives the annular chain, and at least two push rods (151). The annular chain is connected to the push rods, and each push rod extends along the axial direction of the annular chain drive wheel. Each push rod is spaced apart along the extension direction of the annular chain. Each push rod moves with the annular chain to push the material from the loading conveyor (3) to the weighing platform (201) and pushes the material from the weighing platform (201) to the unloading conveyor (4) after weighing. The weighing vision recognition device (19) is used to recognize the weight information displayed by the display module (202). The machine vision-based dynamic weighing system also includes a controller, which is connected to the material pusher (15) to control the operation of the material pusher (15).

2. The machine vision-based dynamic weighing system according to claim 1, characterized in that, The weighing visual recognition device (19) includes a weighing camera (20) for taking pictures of the display module (202), a weighing photography light source (21) for providing light to the symmetrical weighing camera (20), a weighing camera adjustment frame (23), and a light source adjustment frame (22). The weighing camera adjustment frame (23) is used to adjust the shooting angle of the weighing camera (20), and the light source adjustment frame (22) is used to adjust the angle of the light source provided by the weighing photography light source (21) to the symmetrical weighing camera (20).

3. The machine vision-based dynamic weighing system according to claim 2, characterized in that, The weighing camera adjustment frame (23) includes a camera left and right moving rod (231) and a camera up and down moving rod (232). The camera left and right moving rod (231) is guided to move left and right on the frame (1), and the camera up and down moving rod (232) is guided to move up and down on the camera left and right moving rod (231). The weighing camera (20) is rotated and mounted on the camera up and down moving rod (232). The light source adjustment frame (22) includes a light source left and right moving rod (221) and a light source up and down moving rod (222). The light source left and right moving rod (221) is guided to move left and right on the frame (1), and the light source up and down moving rod (222) is guided to move up and down on the light source left and right moving rod (221). The weighing and photographing light source (21) is rotated and mounted on the light source up and down moving rod (222).

4. The machine vision-based dynamic weighing system according to any one of claims 1-3, characterized in that, The weighing platform (201) includes at least two legs (2011) and is fixed to the frame (1) by the legs (2011).

5. The machine vision-based dynamic weighing system according to claim 4, characterized in that, The push rod (151) has a material separation position during the process of pushing the material onto the weighing platform (201). After pushing the material onto the weighing platform (201), the push rod (151) retracts to the material separation position so that the push rod (151) is separated from the material.

6. The machine vision-based dynamic weighing system according to claim 4, characterized in that, The machine vision-based dynamic weighing system also includes a model vision recognition device (5) located upstream of the weighing platform (201). The model vision recognition device (5) is used to identify the model of the material. During the movement, the push rod (151) has a push rod falling position upstream of the model vision recognition device (5). The push rod falling position is located at the corner of the ring chain (152). After the push rod (151) falls to the push rod falling position with the ring chain (152), it moves from the push rod falling position along with the material conveyed by the feeding conveyor (3) to the weighing platform (201) to push the material to the weighing platform (201).

7. The machine vision-based dynamic weighing system according to claim 6, characterized in that, The feeding and conveying device (3) includes multiple spaced conveying rollers (7), which rotate to convey materials. The model visual recognition device (5) includes a push rod (12) for lifting materials. The push rod (12) moves upward from the interval between adjacent conveying rollers (7) to lift the materials on the conveying rollers (7). The model visual recognition device (5) includes a visual recognition module (8) on the right side of the feeding and conveying device (3) and a pushing mechanism (13) for pushing the materials on the push rod (12) toward the visual recognition module (8). The visual recognition module (8) is used to identify the model of the materials. The model visual recognition device (5) also includes a positioning detection sensor (14) for detecting the position of the materials. At least two positioning detection sensors (14) are set in the material conveying direction. After at least two positioning detection sensors (14) detect that the materials are pushed into place by the pushing mechanism (13), the controller controls the pushing mechanism (13) to stop pushing the materials.

8. The machine vision-based dynamic weighing system according to any one of claims 1-3, characterized in that, The machine vision-based dynamic weighing system also includes a model vision recognition device (5) located upstream of the weighing platform (201). The feeding conveying device (3) includes multiple spaced conveying rollers (7). The rotating conveying rollers (7) convey the material. The model vision recognition device (5) includes a push rod (12) for lifting the material. The push rod (12) moves upward from the interval between adjacent conveying rollers (7) to lift the material on the conveying rollers (7). The model vision recognition device (5) includes a vision recognition module (8) located on the right side of the feeding conveying device (3) and a pushing mechanism (13) for pushing the material on the push rod (12) toward the vision recognition module (8). The vision recognition module (8) is used to identify the model of the material. The model vision recognition device (5) also includes a positioning detection sensor (14) for detecting the position of the material. At least two positioning detection sensors (14) are set in the material conveying direction. After at least two positioning detection sensors (14) detect that the material has been pushed into place by the pushing mechanism (13), the controller controls the pushing mechanism (13) to stop pushing the material.

9. The machine vision-based dynamic weighing system according to any one of claims 1-3, characterized in that, The machine vision-based dynamic weighing system also includes a blocking mechanism (16) for preventing subsequent materials from moving onto the weighing platform (201) while the platform is weighing the material.

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