Multi-light-source color sorting device, tomato color sorter and tomato color sorting method
By combining three rows of monochrome LED beads and photoelectric sensors in a multi-light source color sorting device, the problem of low detection accuracy in existing tomato color sorters is solved, achieving efficient and low-cost identification of tomatoes and foreign objects.
Patent Information
- Application Number
- CN202510986729.9
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-07-17
- Publication Date
- 2025-11-28
AI Technical Summary
Existing tomato color sorters have complex light source systems, high costs, and low detection accuracy, making it difficult to effectively distinguish between red tomatoes, green tomatoes, white stones, and black soil, especially in complex environments.
The device employs a multi-light source color sorting system, including three rows of monochrome LED beads (940nm, 870nm, 650nm, and 570nm LED beads). By sequentially illuminating LED beads of different wavelengths and combining this with photoelectric sensors to detect reflected light, it achieves accurate identification of tomatoes and foreign objects.
It improves detection accuracy, reduces equipment costs, minimizes interference from ambient light, avoids dependence on CCD cameras, and enhances equipment durability and detection efficiency.
Smart Images
Figure CN121017119A_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of color sorting machines, in particular, to a multi-light-source color sorting device, a tomato color sorting machine using the multi-light-source color sorting device and a tomato color sorting method. BACKGROUND
[0002] With the development of economy, the market requirements for tomato quality are gradually improved, and tomato color sorting machines have been widely used in the mechanical and automatic harvesting of tomatoes. The main function of the tomato color sorting machine is to quickly pick ripe red tomatoes and remove immature green tomatoes, white stones, black soil blocks and other foreign matters. In the color sorting process, sufficient light and appropriate spectral components need to be provided by the light source system to enable the color sorting machine to complete the color sorting work. Due to the particularity of the sorting objects of the tomato color sorting machine to the spectral characteristics and working environment, the light source has special requirements.
[0003] Specifically, the main principle of the color sorting machine is to irradiate the detected object by the light source system to generate reflected light. Since the reflected light intensity and spectrum of different color objects are different, the sorting of tomatoes is realized by distinguishing the parameters of the reflected light. However, the light source system of the existing tomato color sorting instrument basically adopts a composite white LED light source. In order to achieve sufficient brightness, the light source power needs to be continuously increased, which leads to the need to add a complex heat dissipation device, thereby increasing the equipment cost. Secondly, the composite white light is only suitable for image recognition using a face array CCD camera. For photoelectric sensor recognition, the color sensitivity is low, and it cannot effectively distinguish soil blocks and stones and other foreign matters, which has certain limitations. The use of multiple CCD cameras will further increase the equipment cost, and the calculation processing unit also needs higher configuration. The whole machine design is complex and high in cost. Moreover, the vibration of the tomato harvesting machine will have a great influence on the service life and imaging quality of the CCD camera. More importantly, the color temperature of the composite white light is similar to that of sunlight. The light interference in the outdoor harvesting environment will seriously affect the imaging quality, thereby reducing the detection accuracy. SUMMARY
[0004] The present application primarily provides a multi-light-source color sorting device to solve the technical problems of complex structure, high cost and low detection accuracy of the light source system of the existing tomato color sorting machine.
[0005] The present application also provides a tomato color sorting machine using the above multi-light-source color sorting device.
[0006] The present application also provides a tomato color sorting method using the above multi-light-source color sorting device.
[0007] According to one aspect of the present invention, a multi-light source color sorting device is provided for selecting ripe red tomatoes when installed in a tomato color sorter. The multi-light source color sorting device includes a mounting bracket and a light source circuit board disposed on the side of the mounting bracket. The light source circuit board is provided with a light source module for emitting light toward the item to be inspected, and the mounting bracket is provided with a photoelectric sensor for receiving the reflected light from the item to be inspected.
[0008] The light source module includes three rows of LED beads arranged vertically. Each row of LED beads includes multiple monochromatic LED beads arranged horizontally. The three rows of LED beads are respectively designated as the first row, second row, and third row from top to bottom. The monochromatic LED beads on both sides of the first row are 940nm LED beads, the monochromatic LED beads on both sides of the third row are 870nm LED beads, the monochromatic LED beads in the middle of the first and third rows are 650nm LED beads, and the monochromatic LED beads in the second row are 570nm LED beads. The light source circuit board is used to sequentially illuminate monochromatic LED beads of different wavelengths.
[0009] Preferably, the multi-light source color sorting device further includes a light source cover disposed on the light source module. The light source cover has multiple focusing holes that correspond one-to-one with the multiple monochrome LED beads. The focusing holes are used to constrain the light emission angle of the monochrome LED beads and prevent the light from different monochrome LED beads from interfering with each other.
[0010] Preferably, the light source cover is detachably connected to the light source circuit board.
[0011] Preferably, the light source circuit board is provided on both the upper and lower sides of the mounting bracket, and the end of the light source circuit board away from the mounting bracket is inclined toward the detection area.
[0012] Preferably, the light source circuit board is provided with a plurality of light source modules arranged in the horizontal direction, and the light source modules on the two light source circuit boards are arranged in a one-to-one correspondence.
[0013] Preferably, the multi-light source color sorting device further includes a convex lens disposed at the front end of the photoelectric sensor, the focal point of the convex lens being located at the detection port of the photoelectric sensor and used to converge the reflected light from the object to be detected to the detection port of the photoelectric sensor.
[0014] Preferably, the multi-light source color sorting device further includes a light shield with a cylindrical structure, the light shield being sleeved on the incident end of the convex lens and extending away from the convex lens along the axial direction of the convex lens.
[0015] Preferably, the multi-light source color sorting device further includes a first housing and a transparent window disposed on the first housing. The first housing and the transparent window together enclose a closed cavity. The mounting bracket, the light source circuit board, the light source module and the photoelectric sensor are all disposed in the closed cavity. The light source module and the photoelectric sensor are arranged facing the transparent window.
[0016] As a second aspect, the present invention also provides a tomato color sorter, including the above-mentioned multi-light source color sorting device.
[0017] As a third aspect, the present invention also provides a tomato color sorting method, which employs the above-mentioned multi-light source color sorting device, and the tomato color sorting method includes the following steps:
[0018] S100: Detects whether an item to be inspected has entered the inspection area using 940nm LED beads;
[0019] S200: When the item to be detected enters the detection area, the 940nm LED, 650nm LED, 570nm LED and 870nm LED are lit in sequence, with each single-color LED lasting for 2ms to 10ms.
[0020] S300: It uses photoelectric sensors to detect the reflected light generated by four monochrome LEDs on the object to be tested, combines the four reflected light to determine the color of the object to be tested, and determines the size of the object to be tested based on the time it takes for the object to pass through the detection area.
[0021] The present invention has the following beneficial effects:
[0022] The multi-light source color sorting device provided by this invention includes a light source module comprising multiple monochromatic LED beads, including 940nm LED beads, 870nm LED beads, 650nm LED beads, and 570nm LED beads. The 940nm LED beads are infrared light sources with a wavelength of 940nm, primarily used to detect whether an item to be detected has entered the detection area. The 650nm LED beads are red light sources, and the 570nm LED beads are green light sources. Since ripe red tomatoes absorb green light and reflect red light, while unripe green tomatoes absorb red light and reflect green light, the sequential illumination of the red and green light sources generates different reflected light on the item to be detected. By receiving the reflected light through a photoelectric sensor, red and green tomatoes can be accurately distinguished. Furthermore... The 870nm LED beads are infrared light sources with a wavelength of 870nm. In addition to red and green tomatoes, the items to be detected may also contain white stones and black soil. Since white stones have a very high reflectivity to 870nm light, it is possible to accurately determine whether the items to be detected are foreign objects. In summary, this invention uses four different wavelengths of monochromatic LED beads to generate four types of reflected light on the items to be detected in sequence. Compared with composite white light, it is not affected by ambient light and does not require a costly and vibration-sensitive CCD camera. The color, size and type of the items to be detected can be accurately determined by the detection data of the photoelectric sensor. It has lower computing power requirements. Furthermore, since each monochromatic LED bead is lit sequentially, mutual interference is reduced and instantaneous power is also reduced. The heat dissipation requirements can be met without the need for a complex heat dissipation device.
[0023] Secondly, the light source module includes three rows of LEDs arranged vertically. The monochromatic LEDs on both sides of the first row are 940nm LEDs, which can detect whether an item to be detected has entered the detection area immediately. The monochromatic LEDs on both sides of the third row are 870nm LEDs, which can be used for final inspection to determine whether the item to be detected is a foreign object. In addition, since ripe red tomatoes are larger and take longer to pass through the detection area, while unripe green tomatoes are smaller and take shorter to pass through the detection area, the monochromatic LEDs in the middle of the first and third rows are all 650nm LEDs, which can generate a large area and evenly distributed red light in the detection area to accurately identify the larger red tomatoes. The monochromatic LEDs in the second row are all 570nm LEDs, that is, the green light source is centrally located, which can generate a sufficiently strong green light to ensure that the smaller green tomatoes can be accurately identified when they pass through the detection area quickly. Therefore, this light source arrangement can effectively improve the detection accuracy and achieve the best detection effect.
[0024] In addition to the objectives, features, and advantages described above, the present invention has other objectives, features, and advantages. The invention will now be described in further detail with reference to the figures. Attached Figure Description
[0025] The accompanying drawings, which form part of this application, are used to provide a further understanding of the invention. The illustrative embodiments of the invention and their descriptions are used to explain the invention and do not constitute an undue limitation of the invention. In the drawings:
[0026] Figure 1 This is a schematic diagram of the multi-light source color sorting device provided in an embodiment of the present invention, showing the disassembled state;
[0027] Figure 2 for Figure 1 A schematic diagram of the light source module in the multi-light source color sorting device shown;
[0028] Figure 3 for Figure 1 The diagram shows the assembly structure of the light source cover and the light source circuit board in the multi-light source color sorting device.
[0029] Figure 4 for Figure 3 The diagram shows the optical path of a monochrome LED bead emitting light outwards through the focusing hole of the light source cover.
[0030] Figure 5 for Figure 1 The diagram shows the assembly structure of the light source circuit board and mounting bracket in the multi-light source color sorting device.
[0031] Figure 6 for Figure 5 The diagram shows the usage status of the multi-light source color sorting device.
[0032] Figure 7 This is a schematic diagram of the structure of a tomato color sorter provided in an embodiment of the present invention;
[0033] Figure 8 for Figure 7 The diagram shows the assembly structure of multiple rejection devices in a tomato color sorter.
[0034] Figure 9 for Figure 7 The diagram shows a single rejection device in a tomato color sorter.
[0035] Legend:
[0036] 1. Multi-light source color sorting device; 11. Mounting bracket; 12. Light source circuit board; 13. Light source module; 131. 940nm LED bead; 132. 870nm LED bead; 133. 650nm LED bead; 134. 570nm LED bead; 14. Photoelectric sensor; 15. Light source cover; 151. Focusing hole; 16. Convex lens; 17. Light shield; 18. First housing; 181. Base plate; 182. Outer cover; 183. Hinge; 19. Transparent window; 2. First conveying device; 3. Second conveying device; 4. Rejection device; 41. Linear drive assembly; 411. Cylinder; 42. Spring finger; 421. Baffle; 43. First hinge seat; 44. Second hinge seat; 45. Control valve; 5. Second housing; 51. Receiving cavity; 100. Item to be inspected. Detailed Implementation
[0037] The embodiments of the present invention will be described in detail below with reference to the accompanying drawings. However, the present invention can be implemented in many different ways as defined and covered below. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and should not be construed as limiting the present invention.
[0038] Those skilled in the art will understand that, unless specifically stated otherwise, the term "comprising" as used in this specification means the presence of the stated features, integers, steps, operations, components, and / or components, but does not exclude the presence or addition of one or more other features, integers, steps, operations, components, and / or combinations thereof. It should be understood that when we say a component is "connected" to another component, it can be directly connected to the other component or connected via an intermediate component. The term "and / or" as used herein includes all or any unit and all combinations of one or more associated listed items. The terms "first" and "second," etc., in this specification and claims are used to distinguish different objects, not to describe a particular order.
[0039] Figures 1 to 9 The invention provides a multi-light source color sorting device and a tomato color sorter. The multi-light source color sorting device emits detection light toward the item to be tested and determines the color and type of the item by the different reflected light. By illuminating multiple light sources in a sequential manner, it can accurately identify ripe red tomatoes and improve color sorting accuracy.
[0040] Please combine Figure 1 and Figure 2The multi-light source color sorting device 1 includes a mounting bracket 11 and a light source circuit board 12 disposed on the side of the mounting bracket 11. The light source circuit board 12 is provided with a light source module 13 for emitting light toward the item to be tested. The mounting bracket 11 is provided with a photoelectric sensor 14 for receiving the reflected light from the item to be tested. The photoelectric sensor 14 includes a photodiode.
[0041] Furthermore, the light source module 13 includes three rows of LED beads arranged vertically, each row of LED beads including multiple monochromatic LED beads arranged horizontally. The three rows of LED beads are respectively designated as the first row, second row, and third row of LED beads from top to bottom. The monochromatic LED beads located on both sides of the first row are 940nm LED beads 131, the monochromatic LED beads located on both sides of the third row are 870nm LED beads 132, the monochromatic LED beads located in the middle of the first and third rows are all 650nm LED beads 133, and the monochromatic LED beads in the second row are all 570nm LED beads 134. The light source circuit board 12 is used to sequentially illuminate monochromatic LED beads of different wavelengths. It should be understood that the 940nm LED bead 131 refers to an infrared light source with a wavelength of 970nm, the 870nm LED bead 132 refers to an infrared light source with a wavelength of 870nm, the 650nm LED bead 133 refers to a red light source with a wavelength of 650nm, and the 570nm LED bead 134 refers to a green light source with a wavelength of 570nm.
[0042] The working principle of the multi-light source color sorting device 1 is as follows: the light source module 13 illuminates the object 100 to be detected, and the object 100 generates reflected light. When the reflected light shines on the photodiode, electron-hole pairs are generated, thereby generating photocurrent. Since different intensities and wavelengths of reflected light will cause different current changes, and different colored objects have different reflectivities of different colors of light, by measuring the changes in circuit current or voltage, the intensity or ratio of reflected light can be inferred, thereby detecting the color of the object 100 to be detected. This working principle is completely different from the detection principle of CCD cameras. It does not require the acquisition of high-precision images, nor does it require the setting of complex computing processing units to analyze images. The detection structure is simple, efficient, low-cost, and durable.
[0043] Specifically, in the multi-light source color sorting device 1, the light source module 13 includes multiple monochromatic LED beads, including 940nm LED beads 131, 870nm LED beads 132, 650nm LED beads 133, and 570nm LED beads 134. The 940nm LED bead 131 is an infrared light source with a wavelength of 940nm, mainly used to detect whether the item to be detected 100 has entered the detection area of the light source module 13. The 650nm LED bead 133 is a red light source, and the 570nm LED bead 134 is a green light source. Since ripe red tomatoes absorb green light and reflect red light, while unripe green tomatoes absorb red light and reflect green light, the sequential lighting of the red and green light sources generates different reflected light on the item to be detected 100. The photoelectric sensor 14 receives the reflected light, thus accurately distinguishing between red and green tomatoes. Furthermore, the 870nm LED bead 132 is an infrared light source with a wavelength of 870nm, used to detect whether the item to be detected... In addition to red and green tomatoes, item 100 may also contain white stones and black soil. Since white stones have a very high reflectivity to 870nm light, it is possible to accurately determine whether the item 100 to be tested is a foreign object. In summary, this invention uses four different wavelengths of monochromatic LED beads to generate four types of reflected light on the item 100 to be tested in sequence. Compared with composite white light, it is not affected by ambient light and does not require a costly and vibration-sensitive CCD camera. The color, size and type of the item can be accurately determined by the detection data of the photoelectric sensor 14. It has low computing power requirements. Furthermore, since each monochromatic LED bead is lit sequentially, mutual interference is reduced and instantaneous power is also reduced. It can meet the heat dissipation requirements without the need for a complex heat dissipation device.
[0044] Secondly, the light source module 13 includes three rows of LED beads arranged vertically. The monochromatic LED beads on both sides of the first row are 940nm LED beads 131, which can detect whether the item to be detected 100 has entered the detection area in the first time. The monochromatic LED beads on both sides of the third row are 870nm LED beads 132, which can be used for final inspection to determine whether the item to be detected 100 is a foreign object. In addition, since ripe red tomatoes are larger and take longer to pass through the detection area, while unripe green tomatoes are smaller and take shorter to pass through the detection area, the monochromatic LED beads in the middle of the first and third rows are all 650nm LED beads 133, which can generate a large area and evenly distributed red light in the detection area to accurately identify the larger red tomatoes. The monochromatic LED beads in the second row are all 570nm LED beads 134, that is, the green light source is set in the center, which can generate a sufficiently strong green light to ensure that the smaller green tomatoes can be accurately identified when they pass through the detection area quickly. Therefore, this light source arrangement can effectively improve the detection accuracy and achieve the best detection effect.
[0045] Through testing, it was verified that when different items 100 to be tested passed through the detection area of the multi-light source color sorting device 1, the changes in the detection voltage value (mV) of the photoelectric sensor 14 corresponding to different monochrome LED beads are shown in Tables 1-4 respectively:
[0046] Table 1 shows the changes in detection voltage (mV) when the item to be tested is a red tomato:
[0047] Detection times 650 nm LED lamp beads 570 nm LED lamp beads 940 nm LED lamp beads 870 nm LED lamp beads 1 338 91 206 213 2 336 112 202 220 3 327 106 218 216
[0048] Table 2 shows the changes in detection voltage (mV) when the item to be tested is a green tomato:
[0049] Detection times 650 nm LED lamp beads 570 nm LED lamp beads 940 nm LED lamp beads 870 nm LED lamp beads 1 145 230 214 223 2 165 250 211 225 3 155 239 208 232
[0050] Table 3 shows the changes in detection voltage (mV) when the object to be tested is a white stone:
[0051] Detection times 650 nm LED lamp beads 570 nm LED lamp beads 940 nm LED lamp beads 870 nm LED lamp beads 1 427 223 247 376 2 417 226 234 372 3 419 234 236 372
[0052] Table 4 shows the changes in detection voltage (mV) when the item to be tested is a black clod of soil:
[0053] Detection times 650 nm LED lamp beads 570 nm LED lamp beads 940 nm LED lamp beads 870 nm LED lamp beads 1 132 87 198 185 2 125 85 187 186 3 127 78 192 193
[0054] As can be clearly seen from Tables 1-4, when the item to be detected 100 is a ripe red tomato, it absorbs green light and reflects red light. Therefore, the photoelectric sensor 14 detects a relatively strong 650nm wavelength red reflected light, while the 570nm wavelength green reflected light is relatively weak. This indicates that the item to be detected 100 is a red tomato. At this time, both the 940nm and 870nm wavelength infrared reflected light have a certain intensity, mainly used to confirm that the item to be detected 100 has passed through the detection area, and the time it takes for the item to be detected 100 to pass through the detection area can be used to determine its presence. The size of a red tomato is calculated. Similarly, when the item to be detected 100 is an unripe green tomato, it absorbs red light and reflects green light. Therefore, the photoelectric sensor 14 detects a strong 570nm wavelength green reflected light, while the 650nm wavelength red reflected light is weak, indicating that the item to be detected 100 is a green tomato. At this time, the 940nm and 870nm wavelength infrared reflected light are also used to confirm that the item to be detected 100 has passed through the detection area. Secondly, when the item to be detected 100 is a white stone, it absorbs red light. Both red and green light sources produce strong reflections, making accurate identification difficult using only red and green light sources. However, because white stones have extremely high reflectivity to 870nm wavelength infrared light, when the photoelectric sensor 14 detects strong red and green reflected light, and the detected 870nm wavelength infrared reflected light exceeds a preset voltage threshold, it can accurately determine that the object to be detected 100 is a white stone. Furthermore, when the object to be detected 100 is a black clod of earth, it absorbs a large amount of both red and green light, making identification difficult using only red and green light sources. Accurate identification is possible, but since black soil clods can reflect both 940nm and 870nm infrared light sources with similar reflectivity, when the photoelectric sensor 14 detects strong 940nm and 870nm infrared reflected light, and receives weak 650nm red and 570nm green reflected light, it can accurately determine that a black soil clod has passed through the detection area. Thus, the accurate identification of red tomatoes, green tomatoes, white stones, and black soil clods can be achieved by using four different wavelengths of reflected light.
[0055] Furthermore, each row of LEDs includes three monochromatic LEDs arranged horizontally to form a three-row, three-column matrix structure, achieving a relatively concentrated light source effect and avoiding the impact of excessive spacing between monochromatic LEDs of different wavelengths on the detection performance. In other embodiments, the number of monochromatic LEDs in each row also exceeds three. Increasing the number of monochromatic LEDs enhances the light source intensity and coverage area, meeting the color sorting requirements for a larger detection range.
[0056] Please combine Figure 3 andFigure 4 The multi-source color sorting device 1 further includes a light source cover 15 disposed on the light source module 13. The light source cover 15 has multiple focusing holes 151 corresponding to the multiple monochrome LED beads. The focusing holes 151 are used to constrain the light emission angle of the monochrome LED beads and prevent interference between the light from different monochrome LED beads. In this embodiment, by adjusting the inner diameter and length of the focusing holes 151, the light emission angle of the monochrome LED beads is set to 15°. This ensures the emission effect while effectively preventing interference between the light from different monochrome LED beads. Simultaneously, it enables the focusing effect of each monochrome LED bead, increasing the relative brightness of the detection area and improving the luminous efficiency of the light source.
[0057] In other embodiments, the inner diameter and length of the focusing aperture 151 can be adjusted as needed to adjust the light emission angle of the monochromatic lamp bead. That is, the light emission angle of the monochromatic lamp bead is not limited to 15°, so as to meet different detection requirements.
[0058] Preferably, the light source cover 15 is detachably connected to the light source circuit board 12, so as to disassemble and replace the light source cover 15 of different specifications, thereby flexibly adjusting the light emission angle of the monochrome lamp bead. When the monochrome lamp bead is damaged, the monochrome lamp bead can be directly exposed by removing the corresponding light source cover 15, which facilitates the disassembly and replacement of the monochrome lamp bead.
[0059] Please combine Figure 5 and Figure 6 Preferably, the light source circuit board 12 is provided on both the upper and lower sides of the mounting bracket 11. The end of the light source circuit board 12 away from the mounting bracket 11 is inclined toward the detection area. It should be understood that the detection area refers to the area in which the multi-light source color sorting device 1 can fully illuminate the item to be detected 100 and generate reflected light toward the photoelectric sensor 14 through the item to be detected 100. That is, the detection area is located at the front end of the light emission direction of the light source module 13.
[0060] Because the end of the light source circuit board 12 furthest from the mounting bracket 11 is tilted towards the detection area, the light emission direction of the light source module 13 is tilted towards the mounting bracket 11, thereby ensuring that the reflected light can be accurately reflected back to the detection port of the photoelectric sensor 14, ensuring the detection effect. More importantly, the light source circuit board 12 is provided on both the upper and lower sides of the mounting bracket 11. When the item to be detected 100 enters the detection area, the item to be detected 100 can be simultaneously illuminated by the corresponding light source modules 13 on the two light source circuit boards 12. This increases the light intensity and generates reflected light from different directions. When the shape of the item to be detected 100 is irregular or the light from one of the light source modules 13 cannot be fully reflected to the detection port of the photoelectric sensor 14 due to the influence of ambient light, the light from the light source module 13 in another direction can still be reflected to the detection port of the photoelectric sensor 14, effectively avoiding false detections or missed detections, and further improving the detection accuracy.
[0061] Please combine Figure 1 and Figure 2 The light source circuit board 12 is provided with a plurality of light source modules 13 arranged in the horizontal direction. The light source modules 13 on the two light source circuit boards 12 are arranged in a one-to-one correspondence. The photoelectric sensors 14 are arranged in a one-to-one correspondence with the light source modules 13, so that multiple detection areas are formed by the cooperation of multiple light source modules 13 and multiple photoelectric sensors 14, which can simultaneously perform color sorting operations on multiple items 100 to be inspected, realize batch operations, and improve color sorting efficiency.
[0062] like Figure 6 As shown, preferably, the multi-light source color sorting device 1 further includes a convex lens 16 disposed at the front end of the photoelectric sensor 14. The focal point of the convex lens 16 is located at the detection port of the photoelectric sensor 14 and is used to converge the reflected light from the object to be detected 100 to the detection port of the photoelectric sensor 14. Secondary focusing by the convex lens 16 effectively increases the intensity of the reflected light, improves the detection sensitivity of the photoelectric sensor 14, results in a larger induced current value, and is more conducive to distinguishing object colors, thereby improving detection accuracy.
[0063] Preferably, the multi-source color sorting device 1 further includes a cylindrical light shield 17, which is sleeved on the incident end of the convex lens 16 and extends away from the convex lens 16 along the axial direction of the convex lens 16. The light shield 17 blocks ambient light from other directions, allowing only the light from the detection area to enter the convex lens 16, effectively reducing the interference of ambient light on the reflected light and preventing the convex lens 16 from converging the surrounding ambient light to the detection port of the photoelectric sensor 14.
[0064] likeFigure 1 As shown, the multi-light source color sorting device 1 further includes a first housing 18 and a transparent window 19 disposed on the first housing 18. The first housing 18 and the transparent window 19 together enclose a closed cavity. The mounting bracket 11, the light source circuit board 12, the light source module 13, and the photoelectric sensor 14 are all disposed within the closed cavity. The light source module 13 and the photoelectric sensor 14 are positioned facing the transparent window 19. The transparent window 19 is made of light-transmitting materials such as glass or acrylic sheet to allow light to pass through. The closed cavity formed by the first housing 18 and the transparent window 19 shields and protects the relevant electronic components, preventing foreign objects from entering the interior and affecting the detection accuracy, thus improving the service life.
[0065] Furthermore, the first housing 18 includes a base plate 181 and an outer cover 182 covering the base plate 181, and a hinge 183 disposed between the base plate 181 and the outer cover 182. That is, one side of the outer cover 182 is hinged to the base plate 181 via the hinge 183, so that the outer cover 182 can rotate and open relative to the base plate 181, facilitating the maintenance of components in the enclosed cavity.
[0066] like Figure 7 As shown, as a second aspect, the present invention also provides a tomato color sorter, including the aforementioned multi-light source color sorting device 1. The tomato color sorter is used to sort the items 100 to be inspected according to the color sorting results of the multi-light source color sorting device 1. Since the light source structure of the multi-light source color sorting device 1 is simple and efficient, it can reduce equipment costs and improve color sorting accuracy, thereby improving the sorting precision of the tomato color sorter. This allows the tomato color sorter to quickly select ripe red tomatoes and accurately remove unripe green tomatoes, white stones, black clods of soil, and other foreign objects.
[0067] Furthermore, the tomato color sorter also includes a first conveying device 2, a second conveying device 3, and a rejection device 4. The first conveying device 2 is used to convey the item to be inspected 100. The second conveying device 3 is located below the end of the first conveying device 2 and is arranged vertically at intervals relative to the first conveying device 2. The conveying directions of the first conveying device 2 and the second conveying device 3 are the same. The first conveying device 2 is used to convey the item to be inspected 100 to its end and throw the item to be inspected 100 onto the second conveying device 3 at a certain speed. The multi-light source color sorting device 1 and the rejection device 4 are arranged sequentially along the parabolic trajectory of the item to be inspected 100 after it leaves the first conveying device 2. The rejection device 4 is used to reject unripe tomatoes and foreign objects identified by the multi-light source color sorting device 1, thereby selecting ripe tomatoes and causing the ripe tomatoes to fall onto the second conveying device 3.
[0068] Specifically, both the first conveying device 2 and the second conveying device 3 include a conveyor belt and a conveyor motor for driving the conveyor belt to rotate. Through the cooperation of the first conveying device 2 and the second conveying device 3, the item to be inspected 100 can move a certain distance in the air according to a preset parabolic trajectory, so that color sorting and sorting operations can be performed in the air, avoiding interference of the conveying structure with the color sorting operation, improving the color sorting accuracy and efficiency, and ensuring the sorting effect.
[0069] Preferably, the first conveying device 2 is provided with multiple conveying channels side by side, and the tomato color sorter also includes a grading device (not shown in the figure, the same below) located at the feed end of the first conveying device 2. The grading device is used to grade the items 100 to be tested according to their size and to guide the items 100 to be tested of different size ranges into different conveying channels one by one.
[0070] Furthermore, multiple light source modules 13, photoelectric sensors 14, and rejection devices 4 are provided corresponding to each of the conveying channels, meaning that each conveying channel has an independent detection area at its end. Secondly, the structure and working principle of the grading device are existing technologies and will not be elaborated upon. The grading device guides different sizes of items 100 to be tested into different conveying channels, allowing each conveying channel to transport items 100 of different sizes. This enables each detection area in the multi-light source color sorting device 1 to detect items 100 of different sizes. The illumination time of the monochrome LEDs can be set according to the size. For example, for larger items 10, which take longer to pass through the detection area, the illumination time of each monochrome LED in the corresponding light source module 13 can be extended to improve detection accuracy; conversely, for smaller items 10, which take shorter to pass through the detection area, the illumination time of each monochrome LED in the corresponding light source module 13 can be shortened to avoid missed detections.
[0071] Furthermore, the second conveying device 3 is provided with multiple discharge channels that correspond one-to-one with the multiple conveying channels, so that ripe tomatoes of different sizes can fall into different discharge channels to achieve graded discharge.
[0072] Please combine Figure 8 and Figure 9The tomato color sorter also includes a second housing 5. The rejection device 4 includes a linear drive assembly 41 and a spring finger 42 mounted on the second housing 5. The top end of the spring finger 42 is hinged to the second housing 5. The bottom end of the spring finger 42 is provided with a baffle 421 for rejecting unripe tomatoes or foreign objects. The drive end of the linear drive assembly 41 is hinged to the middle of the spring finger 42 and is used to drive the spring finger 42 to rotate relative to the second housing 5, thereby causing the baffle 421 to swing in a direction closer to or away from the first conveying device 2. The linear drive assembly 41 drives the spring 42 to rotate, which can cause the baffle 421 to swing onto the falling path of the item to be inspected 100 to remove unripe tomatoes and foreign objects. It can also cause the baffle 421 to swing away from the falling path of the item to be inspected 100 so that ripe tomatoes can fall to the second conveying device 3. The sorting structure is simple and efficient. Furthermore, since the driving end of the linear drive assembly 41 is hinged to the middle of the spring 42, the lever principle is used to drive the baffle 421 to swing, which can increase the swing stroke and swing speed of the baffle 421 and realize fast sorting operation.
[0073] Furthermore, the rejection device 4 also includes a first hinge seat 43 and a second hinge seat 44 respectively mounted on the second housing 5. The top end of the spring finger 42 is hinged to the first hinge seat 43, and the fixed end of the linear drive assembly 41 is hinged to the second hinge seat 44, so that the linear drive assembly 41 and the spring finger 42 form a multi-link structure on the second housing 5.
[0074] Furthermore, multiple rejection devices 4 are arranged sequentially on the second housing 5 along a straight line. Each rejection device 4 is installed through an independent first hinge seat 43 and a second hinge seat 44, so that each rejection device 4 can move flexibly, and it is also convenient to disassemble and install any rejection device 4, which is beneficial for later maintenance.
[0075] Preferably, the baffle 421 extends downward and the bottom end of the baffle 421 is inclined along the conveying direction of the first conveying device 2. The inclined structure is more conducive to avoiding the falling path of the item to be tested 100, and can also decelerate and guide the item to be tested 100 that is moving too fast. For example, when the horizontal speed of a ripe tomato is too fast, it can be buffered and decelerated by the baffle 421 and slide down the inclined structure onto the second conveying device 3, preventing it from flying outward.
[0076] Preferably, the second housing 5 has a receiving cavity 51, and the rejection device 4 further includes a control valve 45 disposed within the receiving cavity 51. The linear drive assembly 41 includes a cylinder 411 connected to the control valve 45, and the cylinder 411 is disposed at the bottom of the second housing 5. The receiving cavity 51 shields and protects the control valve 45, and the cylinder 411 is mounted at the bottom of the second housing 5, which facilitates flexible rotation of the spring 42 while preventing foreign objects from falling onto the cylinder 411.
[0077] As a third aspect, the present invention also provides a tomato color sorting method, employing the aforementioned multi-light source color sorting device 1, the tomato color sorting method comprising the following steps:
[0078] Step S100: Detect whether the item to be detected 100 has entered the detection area using a 940nm LED bead 131;
[0079] Step S200: When the item to be detected 100 enters the detection area, the 940nm LED bead 131, 650nm LED bead 133, 570nm LED bead 134, and 870nm LED bead 132 are lit in sequence according to the time interval. The lighting duration of each monochrome LED bead is 2ms to 10ms.
[0080] Step S300: The photoelectric sensor 14 detects the reflected light generated by the four monochrome LED beads on the item to be tested 100, and combines the four reflected light to determine the color of the item to be tested 100, and determines the size of the item to be tested 100 based on the time it takes for the item to be tested 100 to pass through the detection area.
[0081] In this embodiment, the illumination duration of each monochrome LED bead is 5ms with no time interval, ensuring that the smallest diameter item to be detected 100 is detected at least once by each wavelength monochrome LED bead when passing through the detection area at the fastest speed, thus avoiding missed detections. In other embodiments, the illumination duration of each monochrome LED bead can be adjusted between 2ms and 10ms to adapt to items to be detected 100 of different sizes. For example, the illumination duration of the monochrome LED bead should be appropriately shortened for smaller items to be detected 100, and appropriately extended for larger items to be detected 100.
[0082] The tomato color sorting method optimizes the lighting sequence and duration of different monochrome LEDs based on the LED layout of the light source module 13. It prioritizes lighting the 940nm LEDs 131 in the first row to ensure the item 100 fully enters the detection area. Then, it lights the 650nm LEDs 133 with a wider coverage area to provide red light illumination. Next, it lights the 570nm LEDs 134 in the second row with a relatively concentrated coverage area to provide green light illumination. Finally, it lights the 870nm LEDs 132 in the third row to detect foreign objects. This method enables the sequential and thorough detection of multiple light sources during the falling process of the item 100, achieving optimal detection results. Secondly, the illumination duration of each monochrome LED bead is 2ms to 10ms. This ensures the illumination effect of each monochrome LED bead while guaranteeing that all four monochrome LED beads can illuminate the item to be detected 100. When the illumination duration of each monochrome LED bead is less than 2ms, the illumination intensity will decrease, and the light from different monochrome LED beads will interfere with each other, causing the photoelectric sensor 14 to be unable to accurately identify the reflected light. Conversely, when the illumination duration of each monochrome LED bead exceeds 10ms, smaller items to be detected 100 may not be illuminated sequentially by the four monochrome LED beads when passing quickly through the detection area, which will also affect the detection effect. Therefore, the tomato color sorting method, by setting the illumination order and duration of different monochrome LED beads, can ensure the color sorting effect, thereby enabling the accurate identification of red tomatoes, green tomatoes, white stones, and black soil using four different wavelengths of reflected light.
[0083] The above description is merely a preferred embodiment of the present invention and is not intended to limit the invention. Various modifications and variations can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.
Claims
1. A multi-light source color sorting device, used for installation in a tomato color sorter to select ripe red tomatoes, characterized in that, The multi-light source color sorting device includes a mounting bracket (11) and a light source circuit board (12) disposed on the side of the mounting bracket (11). The light source circuit board (12) is provided with a light source module (13) for emitting light toward the item to be tested (100). The mounting bracket (11) is provided with a photoelectric sensor (14) for receiving the reflected light from the item to be tested (100). The light source module (13) includes three rows of LED beads arranged vertically. Each row of LED beads includes multiple monochromatic LED beads arranged horizontally. The three rows of LED beads are respectively designated as the first row, the second row, and the third row from top to bottom. The monochromatic LED beads located on both sides of the first row are designated as 940nm LED beads (131). The monochromatic LED beads located on both sides of the third row are designated as 870nm LED beads (132). The monochromatic LED beads located in the middle of the first and third rows are designated as 650nm LED beads (133). The monochromatic LED beads in the second row are designated as 570nm LED beads (134). The light source circuit board (12) is used to sequentially light up monochromatic LED beads of different wavelengths.
2. The multi-light source color sorting device according to claim 1, characterized in that, The multi-source color sorting device also includes a light source cover (15) covering the light source module (13). The light source cover (15) has multiple focusing holes (151) that correspond one-to-one with the multiple monochrome LED beads. The focusing holes (151) are used to constrain the light emission angle of the monochrome LED beads and prevent the light from different monochrome LED beads from interfering with each other.
3. The multi-light source color sorting device according to claim 2, characterized in that, The light source cover (15) is detachably connected to the light source circuit board (12).
4. The multi-light source color sorting device according to claim 1, characterized in that, The mounting bracket (11) is provided with the light source circuit board (12) on both the upper and lower sides, and the end of the light source circuit board (12) away from the mounting bracket (11) is tilted towards the detection area.
5. The multi-light source color sorting device according to claim 4, characterized in that, The light source circuit board (12) is provided with a plurality of light source modules (13) arranged in the horizontal direction, and the light source modules (13) on the two light source circuit boards (12) are arranged in a one-to-one correspondence.
6. The multi-light source color sorting device according to claim 1, characterized in that, The multi-light source color sorting device also includes a convex lens (16) disposed at the front end of the photoelectric sensor (14). The focal point of the convex lens (16) is located at the detection port of the photoelectric sensor (14) and is used to converge the reflected light of the item to be detected (100) to the detection port of the photoelectric sensor (14).
7. The multi-light source color sorting device according to claim 6, characterized in that, The multi-light source color sorting device also includes a light shield (17) with a cylindrical structure. The light shield (17) is sleeved on the incident end of the convex lens (16) and extends away from the convex lens (16) along the axial direction of the convex lens (16).
8. The multi-light source color sorting device according to claim 1, characterized in that, The multi-light source color sorting device further includes a first housing (18) and a transparent window (19) disposed on the first housing (18). The first housing (18) and the transparent window (19) together enclose a closed cavity. The mounting bracket (11), the light source circuit board (12), the light source module (13) and the photoelectric sensor (14) are all disposed in the closed cavity. The light source module (13) and the photoelectric sensor (14) are arranged facing the transparent window (19).
9. A tomato color sorter, characterized in that, Includes the multi-light source color sorting device as described in any one of claims 1 to 8.
10. A method for color sorting tomatoes, characterized in that, The tomato color sorting method, employing the multi-light source color sorting device as described in any one of claims 1 to 8, includes the following steps: S100: Detects whether an item to be tested (100) has entered the detection area using 940nm LED beads (131); S200: When the item to be detected (100) enters the detection area, 940nm LED beads (131), 650nm LED beads (133), 570nm LED beads (134), and 870nm LED beads (132) are lit in sequence in a time-division manner. The lighting duration of each monochrome LED bead is 2ms to 10ms. S300: The photoelectric sensor (14) detects the reflected light generated by the four monochrome LED beads on the item to be tested (100), and combines the four reflected light to judge the color of the item to be tested (100), and judges the size of the item to be tested (100) based on the time it takes for the item to be tested (100) to pass through the detection area.