A sampling device and sampling method for detecting microplastics in farmland soil

Abstract

The application provides a sampling device and method for detecting farmland soil microplastics, and belongs to the field of soil microplastic detection sampling devices. The device comprises a box body, a soil sample supporting unit and a soil sample flattening unit. The soil sample flattening unit comprises a scraper, a rotating assembly and an up-down lifting assembly. The rotating assembly drives the scraper to rotate, and the up-down lifting assembly drives the scraper to lift. The soil sample dividing unit comprises a plurality of pressing blocks, a front-back moving assembly and a left-right moving assembly. The front-back moving assembly drives the scraper to move forward and backward, and the left-right moving assembly drives the scraper to move left and right. The soil sample flattening unit and the soil sample dividing unit can realize the rotation and descent of the scraper, flatten the soil sample, and divide the flattened soil sample into four parts through the forward-backward and left-right movement of the scraper. Then, two parts are discarded, the soil sample is taken, and the operation steps of the four-part sampling method can be fully and truly simulated, so that the representativeness of the sampling can be ensured.

Description

Technical Field

[0001] This invention belongs to the field of soil microplastic detection and sampling devices, and in particular relates to a sampling device and sampling method for detecting microplastics in farmland soil. Background Technology

[0002] Microplastics, as one of the four major emerging pollutants, have become a key focus of global ecological and environmental concerns. Farmland soil is a significant accumulation site for microplastics. The migration and transformation of microplastics in farmland soil can alter the ecotoxicity of heavy metals and persistent organic pollutants, threatening food safety. Therefore, monitoring microplastics in farmland soil is necessary to provide a scientific basis for microplastic risk control.

[0003] When monitoring microplastics in farmland soil, soil samples are taken using specific methods (diagonal sampling, quincunx sampling, checkerboard sampling, serpentine sampling, or soil auger sampling, etc.). All soil samples are then mixed and discarded using a quartering method to improve the representativeness of the soil samples. For the quartering method, all soil is first piled into a cone shape. The cone-shaped soil sample is then flattened into a frustum shape using scraping and pressing techniques, and then divided into four portions, from which two portions are taken.

[0004] Chinese invention patent CN107643190A discloses "An Asphalt Mixture Mixing and Quartering Sampling Device and Sampling Method", which specifically discloses a silo, an internal bucket, and a dividing component. The dividing component divides the silo into four parts. When the sample is mixed from above and falls into the silo, it will be divided into four parts, thereby realizing the quartering sampling of the sample. However, this technical solution divides the sample into four parts during the fall, but does not follow the normal quartering process. It simply divides the sample into four parts, and its sampling is not representative. Summary of the Invention

[0005] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a sampling device and sampling method for detecting microplastics in farmland soil, which solves the problem that the prior art simply divides the sample into four parts, and the sampling is not representative.

[0006] To achieve the above and other related objectives, the present invention provides a sampling device for detecting microplastics in farmland soil, the sampling device comprising:

[0007] The container has a soil sample inlet.

[0008] A soil sample support unit, comprising a support plate and a flexible film; the support plate is fixed inside a box, with a gap between the support plate and the box, and the flexible film is placed on the transparent support plate, with the soil samples to be separated stacked in a cone shape on the flexible film;

[0009] The soil sample leveling unit includes a scraper, a rotating assembly, and an up-and-down lifting assembly. The scraper is installed inside the box. The rotating assembly drives the scraper to rotate, and the up-and-down lifting assembly drives the scraper to rise and fall. The rotation axis of the scraper is parallel to the lifting direction of the scraper, and the rotation axis of the scraper is perpendicular to the upper end face of the support plate. The scraper rotates and descends to level the soil sample to be divided.

[0010] The soil sample division unit includes several clamping blocks, a front-to-back moving assembly, and a left-to-right moving assembly. The clamping blocks are all raised and lowered inside the housing. The clamping blocks are used to press the flexible film onto the support plate. The front-to-back moving assembly drives the scraper to move back and forth, and the left-to-right moving assembly drives the scraper to move left and right. The front-to-back movement direction, the left-to-right movement direction, and the up-and-down movement direction of the scraper are perpendicular to each other.

[0011] As an optional solution, the scraper includes a main scraper, a through groove, a first auxiliary scraper, a second auxiliary scraper, and a telescopic power module;

[0012] The main scraper has a through groove along its length direction. A first auxiliary scraper and a second auxiliary scraper are slidably installed in the through groove along its length direction. The first auxiliary scraper and the second auxiliary scraper slide in opposite directions along the length direction of the through groove and can extend out of the main scraper.

[0013] The telescopic power module is fixedly installed on the main scraper. The telescopic power module includes two telescopic ends. One of the telescopic ends of the telescopic power module is fixedly connected to the first auxiliary scraper and drives the first auxiliary scraper to slide. The other telescopic end of the telescopic power module is fixedly connected to the second auxiliary scraper and drives the second auxiliary scraper to slide.

[0014] The rotating assembly drives the main scraper to rotate.

[0015] As an optional solution, the rotating assembly includes a rotating plate and a first rotational power source;

[0016] The rotating plate is rotatably installed inside the box, and the rotation axis of the rotating plate is perpendicular to the upper end face of the support plate. The first rotation power source drives the rotating plate to rotate.

[0017] The rotating plate rotates, causing the scraper to rotate.

[0018] As an optional solution, the lifting assembly includes a lifting power source;

[0019] One end of the lifting power source is fixedly installed on the rotating plate, and the other end of the lifting power source is fixedly connected to the scraper. The lifting power source drives the scraper to move up and down.

[0020] As an optional solution, the forward and backward moving assembly includes a sliding plate, a first slider, a first sliding rod, and a second telescopic power source;

[0021] The first slider is slidably mounted on the front wall / rear wall of the housing;

[0022] The first slide rod is fixedly installed on the first slider. The axis of the first slide rod is perpendicular to the front wall of the box. The direction of the axis of the first slide rod is perpendicular to the sliding direction of the first slider. The sliding plate is slidably connected to the first slide rod.

[0023] The second telescopic power source is fixedly installed on the first slider, and the telescopic end of the second telescopic power source is fixedly connected to the sliding plate;

[0024] The rotating plate is rotatably mounted on the lower end face of the sliding plate.

[0025] As an optional solution, the left and right moving component includes a second slider, a second sliding rod, and a third telescopic power source;

[0026] The second slider is slidably mounted on the left wall / right wall of the box, and the sliding direction of the second slider is parallel to the axial direction of the first slider.

[0027] The second slide rod is fixedly installed on the first slider, the axis of the second slide rod is parallel to the sliding direction of the first slider, and the second slide rod is slidably connected to the sliding plate;

[0028] The third telescopic power source is fixedly installed on the second slider, and the telescopic end of the third telescopic power source is fixedly connected to the sliding plate. The sliding direction of the second slider is parallel to the axial direction of the first slider.

[0029] As an optional solution, the soil sample segmentation unit also includes several pressing power components that drive several pressing blocks to press the flexible film. The several pressing power components are arranged in a circular array around the center line of the flexible film. Each of the several pressing power components includes a fourth telescopic power source and a fifth telescopic power source.

[0030] The fourth telescopic power source is fixedly installed on the inner wall of the box, and the telescopic direction of the fourth telescopic power source is parallel to the upper end face of the support plate.

[0031] The fifth telescopic power source is fixedly installed at the telescopic end of the fourth telescopic power source. The telescopic direction of the fifth telescopic power source is perpendicular to the upper surface of the support plate. The pressing block is fixedly installed at the telescopic end of the fifth telescopic power source. The pressing block descends and presses the flexible film onto the support plate.

[0032] As an optional solution, the sampling device further includes a positioning unit for measuring the center point of the soil sample to be divided, the positioning unit including a controller and an image contour acquisition device;

[0033] The image contour collector is fixed above the flexible film, and the data acquisition end of the image contour collector faces the soil sample to be separated. The image contour collector acquires the outer contour data of the soil sample to be separated.

[0034] The signal input terminal of the controller is electrically connected to the signal output terminal of the image acquisition device, the first signal output terminal of the controller is electrically connected to the signal input terminal of the second telescopic power source, and the second signal output terminal of the controller is electrically connected to the signal input terminal of the third telescopic power source.

[0035] As an optional solution, the sampling device further includes a gathering unit for re-gathering the soil sample to be separated after it has been spread out on the flexible film. The gathering unit includes at least three gathering components, and the at least three gathering components are arranged in a circular array at equal angles around the center line of the flexible film.

[0036] Each of the gathering components includes a second rotational power source, a steel wire, a winding reel, a sixth telescopic power source, and a sleeve.

[0037] The sixth telescopic power source is fixedly installed inside the box, and the telescopic direction of the sixth telescopic power source is perpendicular to the lifting direction of the scraper. The sleeve is fixedly installed at the telescopic end of the sixth telescopic power source.

[0038] The second rotational power source is fixedly installed inside the housing, and the winding reel is fixedly installed on the rotational power output end of the second rotational power source. One end of the steel wire is fixedly connected to the winding reel, and the other end of the steel wire passes through the sleeve and is detachably connected to the flexible film.

[0039] The present invention also proposes a sampling method based on the above-described sampling device, the sampling method comprising:

[0040] Flexible film pressing steps: Activate the fourth telescopic power source to move the pressing block above the flexible film, and activate the fifth telescopic power source to lower the pressing block and press the flexible film.

[0041] Soil leveling steps: Start the lifting power source to drive the scraper to descend, start the first rotation power source to drive the rotating plate to rotate, thereby driving the scraper to rotate while descending. When the scraper comes into contact with the soil sample to be separated, the rotating scraper will level the part of the soil sample that is in contact with the scraper. The scraper continues to descend to level the entire soil sample to be separated.

[0042] Soil four-part division process: After the soil sample to be divided is flattened, the outer contour of the flattened soil sample is captured by the image contour acquisition device. The center point is analyzed by the controller. The second and third telescopic power sources are activated to drive the scraper to move above the center point of the flattened soil sample to achieve the positioning of the scraper. The scraper descends and inserts into the flattened soil sample to be divided. The second and third telescopic power sources are activated in sequence to make the scraper move left and right and back and forth in sequence, thereby dividing the flattened soil sample into four parts.

[0043] Soil disposal steps: Activate the second and third telescopic power sources to move the scraper to one side of one of the soil samples and push the soil sample out of the support plate, thereby discarding the soil sample.

[0044] Soil re-aggregation steps: The second rotational power source of different re-aggregation components is activated in sequence to wind the steel wire onto the winding reel, thereby lifting the flexible film in sequence and re-aggregating the flattened soil sample into a cone shape.

[0045] As described above, the sampling device and method for detecting microplastics in farmland soil according to the present invention have at least the following beneficial effects:

[0046] 1. This application, through the setting of soil sample leveling units and soil sample segmentation units, can fully and realistically simulate the operation steps of the quartering method sampling, thereby ensuring the representativeness of the sampling;

[0047] 2. During the process of spreading the soil sample, the soil sample rotates with the scraper, which allows for thorough mixing. This application, by setting a main scraper, a first auxiliary scraper, and a second auxiliary scraper, can increase the length of the scraper, allowing the soil sample to be spread to a larger size, thereby spreading the soil sample into a thinner sample and ensuring the mixing effect of the soil sample.

[0048] 3. This application uses at least three gathering components. By activating the gathering components clockwise or counterclockwise in sequence, one corner of the flexible film can be lifted in turn, and the flattened soil can be gathered again. This allows for multiple quartering of the soil sample for rejection, further ensuring that the weight of the remaining sample meets the requirements.

[0049] 4. Due to the fragile nature of microplastics in farmland soil, this application uses the rotation and descent of a scraper to gently level the soil sample, thereby avoiding the breakage of microplastics in the farmland soil during the leveling process. Attached Figure Description

[0050] Figure 1 The diagram shown is a schematic representation of the structure of the present invention.

[0051] Figure 2The diagram shown is an exploded view of the soil sample leveling unit, the front-to-back moving component, and the left-to-right moving component of the present invention.

[0052] Figure 3 Shown is a partial structural cross-sectional view of the scraper of the present invention;

[0053] Figure 4 The diagram shown is a structural schematic of the main scraper of the present invention.

[0054] Figure 5 The diagram shows a structural cross-sectional view of the box body, soil sample support unit, and convergence unit of the present invention.

[0055] Figure 6 Shown as the present invention Figure 5 A magnified view of point A in the image;

[0056] Figure 7 The diagram shown is a structural schematic of the gathering unit of the present invention.

[0057] In the diagram: 101. Box body; 102. Entrance;

[0058] 201. Support plate; 202. Flexible film; 203. Soil sample to be separated;

[0059] 301. Main scraper; 302. Through groove; 303. First auxiliary scraper; 304. Second auxiliary scraper; 305. Telescopic power module;

[0060] 311. Rotating plate; 312. First rotational power source;

[0061] 321. Lifting power source;

[0062] 401. Clamping block; 402. Fourth telescopic power source; 403. Fifth telescopic power source;

[0063] 411. Sliding plate; 412. First slider; 413. First sliding rod; 414. Second telescopic power source;

[0064] 421. Second slider; 422. Second sliding rod; 423. Third telescopic power source;

[0065] 501. Image contour acquisition device;

[0066] 601. Second rotational power source; 602. Steel wire; 603. Winding reel; 604. Sixth telescopic power source; 605. Sleeve. Detailed Implementation

[0067] The following specific embodiments illustrate the implementation of the present invention. Those skilled in the art can easily understand other advantages and effects of the present invention from the content disclosed in this specification.

[0068] Please see Figures 1 to 7 It should be understood that the structures, proportions, sizes, etc., depicted in the accompanying drawings are merely for illustrative purposes to aid those skilled in the art and to facilitate understanding. They are not intended to limit the scope of the invention and therefore have no substantial technical significance. Any modifications to the structure, changes in proportions, or adjustments to size, without affecting the effectiveness and purpose of the invention, should still fall within the scope of the technical content disclosed herein. Furthermore, the terms "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and not intended to limit the scope of the invention. Changes or adjustments to their relative relationships, without substantially altering the technical content, should also be considered within the scope of the invention.

[0069] The following embodiments are for illustrative purposes only. These embodiments can be combined and are not limited to the content shown in any single embodiment below.

[0070] Please see Figures 1 to 7 This invention provides a sampling device for detecting microplastics in farmland soil, comprising:

[0071] The box 101 has an entrance on its side wall and a door panel that is rotatably installed on its side wall, which opens and closes the entrance.

[0072] The soil sample support unit includes a support plate 201 and a flexible film 202. The support plate 201 is fixed inside the box 101, and there is a gap between the support plate 201 and the box 101. The internal space of the box 101 is rectangular, the support plate 201 is cylindrical, and the flexible film 202 is placed on the transparent support plate 201. The soil samples 203 to be separated are stacked in a cone shape on the flexible film 202.

[0073] Meanwhile, an annular groove 302 is provided through the bottom wall of the box 101. The annular groove 302 divides the bottom wall of the box 101 into an outer ring plate and an inner ring plate. The outer ring plate and the inner ring plate are fixedly connected by a connecting block. A baffle is fixedly connected between the bottom end face of the support plate 201 and the upper end face of the inner ring plate. The outer boundary of the lower end face of the baffle coincides with the boundary of the upper end face of the inner ring plate. The baffle is used to ensure that the soil sample can fall normally out of the box 101 through the annular groove 302 when the soil sample falls from the support plate 201.

[0074] The flexible film 202 here is a non-stretchable film material. The flexible film 202 is larger than the support plate 201. When the flexible film 202 is placed on the support plate 201, part of the flexible film 202 hangs down from the upper end of the support plate 201.

[0075] The soil sample leveling unit includes a scraper, a rotating assembly, and a lifting assembly. The scraper is installed inside the housing 101. The rotating assembly drives the scraper to rotate, and the lifting assembly drives the scraper to rise and fall. The rotation axis of the scraper is parallel to the lifting direction of the scraper, and the rotation axis of the scraper is perpendicular to the upper surface of the support plate 201. The scraper rotates and descends to level the soil sample 203 to be divided.

[0076] The soil sample division unit includes several clamping blocks 401, a front-to-back moving assembly, and a left-to-right moving assembly. The clamping blocks 401 are all raised and lowered inside the housing 101. The clamping blocks 401 are used to press the flexible film 202 onto the support plate 201. The front-to-back moving assembly drives the scraper to move back and forth, and the left-to-right moving assembly drives the scraper to move left and right. The front-to-back movement direction, the left-to-right movement direction, and the up-and-down movement direction of the scraper are perpendicular to each other.

[0077] The door panel is opened, and a cone-shaped soil sample 203 is placed onto the flexible film 202 through the inlet. The lifting and lowering assembly drives the scraper to descend, while the rotating assembly drives the scraper to rotate. During the rotation and descent of the scraper, the soil sample 203 is flattened. After flattening, the clamping block 401 descends and presses the flexible film 202 onto the support plate 201. The rotating assembly is then activated to drive the scraper to rotate, making the scraper's length direction lateral. The scraper descends, and its lower end is inserted into the flattened soil sample. When the lower end of the scraper is in contact with the upper end of the flexible film 202, the front and back moving component is activated, which moves the scraper back and forth, thereby dividing the flattened soil sample into two parts. The scraper rises, causing it to detach from the soil sample. The rotating component is activated, which rotates the scraper 90 degrees. The scraper descends, and the lower end of the scraper is in contact with the upper end of the flexible film 202. The left and right moving component is activated, which moves the scraper left and right, thereby dividing the flattened soil sample into four parts: upper left soil sample, lower left soil sample, upper right soil sample, and lower right soil sample.

[0078] The forward and backward moving component moves the scraper forward, positioning it between the lower left and lower right soil samples. The left and right moving component moves the scraper to the left, pushing the lower left soil sample out of the support plate 201. The lower left soil sample falls through the gap between the support plate 201 and the box 101, thus discarding the lower left soil sample. The forward and backward moving component moves the scraper backward, positioning it between the upper left and upper right soil samples. The left and right moving component moves the scraper to the right, pushing the upper right soil sample out of the support plate 201. The upper right soil sample falls through the gap between the support plate 201 and the box 101, thus discarding the upper right soil sample. This is a four-part method for discarding soil samples.

[0079] In this embodiment, please refer to Figures 1 to 7 The scraper includes a main scraper 301, a through groove 302, a first auxiliary scraper 303, a second auxiliary scraper 304, and a telescopic power module 305;

[0080] A through groove 302 is provided on the main scraper 301 along its length direction. A first auxiliary scraper 303 and a second auxiliary scraper 304 are slidably installed in the through groove 302 along its length direction. The first auxiliary scraper 303 and the second auxiliary scraper 304 slide in opposite directions along the length direction of the through groove 302 and can extend out of the main scraper 301. That is, the first auxiliary scraper 303 slides to the left and extends out of the main scraper 301, and the second auxiliary scraper 304 slides to the right and extends out of the main scraper 301.

[0081] The lower end face of the main scraper 301 is provided with a guide slope. After the soil sample is flattened, the main scraper 301 can be inserted into the bottom of the flattened soil sample, which makes it easier to flatten the soil sample into four parts. At the same time, the guide slope can also naturally separate the soil sample when the main scraper 301 is inserted into the soil sample, making it easier to insert into the flattened soil sample. Moreover, when the main scraper 301 is inserted into the bottom wall of the soil sample, it can also avoid breaking the microplastics in the soil sample.

[0082] The telescopic power module 305 is fixedly installed on the main scraper 301. The telescopic power module 305 includes two telescopic ends. One telescopic end of the telescopic power module 305 is fixedly connected to the first auxiliary scraper 303 and drives the first auxiliary scraper 303 to slide. The other telescopic end of the telescopic power module 305 is fixedly connected to the second auxiliary scraper 304 and drives the second auxiliary scraper 304 to slide.

[0083] One embodiment of the telescopic power module 305 is a bidirectional hydraulic cylinder with two telescopic rods. The two telescopic rods extend or retract simultaneously, and the extension and retraction directions of the two telescopic rods are opposite. The bidirectional hydraulic cylinder is fixedly installed on the main scraper 301, and the two telescopic rods are respectively fixedly connected to the first auxiliary scraper 303 and the second auxiliary scraper 304.

[0084] Another embodiment of the telescopic power module 305 is two electric telescopic rods, both of which are fixedly installed on the main scraper 301. The two electric telescopic rods are arranged back to back, and the telescopic ends of the two electric telescopic rods are respectively fixedly connected to the first auxiliary scraper 303 and the second auxiliary scraper 304.

[0085] The rotating assembly drives the main scraper 301 to rotate.

[0086] The telescopic power module 305 can drive the first auxiliary scraper 303 and the second auxiliary scraper 304 to extend outward, thereby increasing the length of the main scraper 301. When the main scraper 301 rotates, it can increase the soil spreading area, thus spreading the soil thinner.

[0087] Meanwhile, since the first auxiliary scraper 303 and the second auxiliary scraper 304 are slidably installed with the chute, there is a certain distance between the lower end face of the first auxiliary scraper 303 and the lower end face of the main scraper 301. When dividing the leveled soil sample into four parts, the main scraper 301 can first draw a straight line on the leveled soil sample to divide it into two halves. Then, the main scraper 301 is moved to the middle position of the straight line, and a part of the leveled soil sample is pushed backward. Then, the main scraper 301 is moved to the left side of the straight line, and the soil sample missing below the first auxiliary scraper 303 is also pushed backward. Then, the main scraper 301 is moved to the right side of the straight line, and the soil sample missing below the second auxiliary scraper 304 is also pushed backward, thereby dividing the soil sample into two parts. When it is necessary to divide the soil sample into four parts with the main scraper 301, the main scraper 301 is rotated 90 degrees and moved left and right to divide the soil sample into four parts.

[0088] In this embodiment, please refer to Figures 1 to 7 The rotating assembly includes a rotating plate 311 and a first rotational power source 312;

[0089] The rotating plate 311 is rotatably installed inside the housing 101. The rotation axis of the rotating plate 311 is perpendicular to the upper end face of the support plate 201. The first rotation power source 312 drives the rotating plate 311 to rotate.

[0090] The first rotational power source 312 is a motor. The motor can directly drive the rotating plate 311 to rotate; it can also drive the rotating plate 311 to rotate through a gear set (a rotating shaft is fixedly installed on the rotating plate 311, and the rotating shaft and the motor output shaft are transmitted through a gear set); or it can drive the rotating plate 311 to rotate through a belt (a rotating shaft is fixedly installed on the rotating plate 311, and the rotating shaft and the motor output shaft are transmitted through a belt).

[0091] The rotating plate 311 rotates, causing the scraper to rotate. By controlling the rotation speed of the rotating plate 311, it is possible to avoid excessive force between the scraper and the soil sample when the scraper rotates, thereby avoiding damage to the microplastics in the soil sample.

[0092] The first rotational power source 312 is started to drive the rotating plate 311 to rotate, thereby driving the scraper to rotate.

[0093] In this embodiment, please refer to Figures 1 to 7 The lifting assembly includes a lifting power source 321;

[0094] One end of the lifting power source 321 is fixedly installed on the rotating plate 311, and the other end of the lifting power source 321 is fixedly connected to the scraper. The lifting power source 321 drives the scraper to move up and down.

[0095] The lifting power source 321 is not limited here. It provides lifting power for the scraper and can be an electric telescopic rod, a hydraulic cylinder, or a pneumatic cylinder.

[0096] The lifting power source 321 can drive the scraper to rise and fall. When the scraper rotates, it also lowers, thereby flattening the soil sample 203 to be divided.

[0097] In this embodiment, please refer to Figures 1 to 7 The forward and backward moving assembly includes a sliding plate 411, a first slider 412, a first sliding rod 413, and a second telescopic power source 414;

[0098] The first slider 412 is slidably installed on the front wall / rear wall of the housing 101. The first slider 412 is slidably installed in the groove by opening a groove on the left wall or right wall of the housing 101.

[0099] The first slide rod 413 is fixedly installed on the first slider 412. The axis of the first slide rod 413 is perpendicular to the front wall of the housing 101. The direction of the axis of the first slide rod 413 is perpendicular to the sliding direction of the first slider 412. The sliding plate 411 is slidably connected to the first slide rod 413.

[0100] The second telescopic power source 414 is fixedly installed on the first slider 412, and the telescopic end of the second telescopic power source 414 is fixedly connected to the sliding plate 411;

[0101] The second telescopic power source 414 is not limited here. It provides forward and backward sliding power for the sliding plate 411. It can be an electric telescopic rod, a hydraulic cylinder, or a pneumatic cylinder.

[0102] The rotating plate 311 is rotatably mounted on the lower end face of the sliding plate 411.

[0103] The second telescopic power source 414 is activated, thereby driving the sliding plate 411 to slide, which in turn drives the scraper to move back and forth.

[0104] In this embodiment, please refer to Figures 1 to 7 The left and right moving component includes a second slider 421, a second slider 422 and a third telescopic power source 423;

[0105] The second slider 421 is slidably installed on the left wall / right wall of the housing 101. The sliding direction of the second slider 421 is parallel to the axial direction of the first slider 413. The second slider 421 is slidably installed in the groove by opening a groove on the left wall or the right wall of the housing 101.

[0106] The second slide rod 422 is fixedly installed on the first slider 412. The axial direction of the second slide rod 422 is parallel to the sliding direction of the first slider 412. The second slide rod 422 is slidably connected to the sliding plate 411.

[0107] The third telescopic power source 423 is fixedly installed on the second slider 421. The telescopic end of the third telescopic power source 423 is fixedly connected to the sliding plate 411. The sliding direction of the second slider 421 is parallel to the axial direction of the first slider 413.

[0108] The third telescopic power source 423 is not limited here. It provides left and right sliding power for the sliding plate 411. It can be an electric telescopic rod, a hydraulic cylinder, or a pneumatic cylinder.

[0109] The third telescopic power source 423 is activated, thereby driving the sliding plate 411 to slide, which in turn drives the scraper to move left and right.

[0110] At the same time, when the lower end of the scraper descends and inserts into the leveled soil sample, the scraper can be divided into four parts by moving left and right and forward and backward, which is convenient for subsequent disposal.

[0111] In this embodiment, please refer to Figures 1 to 7 The soil sample division unit also includes several pressing power components that drive several pressing blocks 401 to press the flexible film 202. The several pressing power components are arranged in a circular array around the center line of the flexible film 202. Each of the several pressing power components includes a fourth telescopic power source 402 and a fifth telescopic power source 403.

[0112] The fourth telescopic power source 402 and the fifth telescopic power source 403 are not limited here; they can be electric telescopic rods, hydraulic cylinders, pneumatic cylinders, etc.

[0113] The fourth telescopic power source 402 is fixedly installed on the inner wall of the housing 101, and the telescopic direction of the fourth telescopic power source 402 is parallel to the upper end face of the support plate 201; the fifth telescopic power source 403 is fixedly installed on the telescopic end of the fourth telescopic power source 402, and the telescopic direction of the fifth telescopic power source 403 is perpendicular to the upper end face of the support plate 201; the pressing block 401 is fixedly installed on the telescopic end of the fifth telescopic power source 403; the pressing block 401 descends and presses the flexible film 202 onto the support plate 201.

[0114] Activating the fourth telescopic power source 402 causes the fifth telescopic power source 403 to extend forward and move the clamping block 401 above the flexible film 202. Activating the fifth telescopic power source 403 causes the clamping block 401 to move downward, thereby pressing the flexible film 202 onto the support plate 201. This avoids the problem of the flexible film 202 shifting position when the scraper divides the leveled soil sample into quarters.

[0115] In this embodiment, please refer to Figures 1 to 7 The sampling device also includes a positioning unit for measuring the center point of the soil sample 203 to be divided, the positioning unit including a controller and an image contour acquisition device 501;

[0116] The image contour collector 501 is fixed above the flexible film 202, and the data acquisition end of the image contour collector 501 faces the soil sample 203 to be separated. The image contour collector 501 acquires the outer contour data of the soil sample 203 to be separated.

[0117] The image contour acquisition device 501 acquires image data above the soil sample 203 to be divided, and then calculates its center point through the controller;

[0118] The signal input terminal of the controller is electrically connected to the signal output terminal of the image acquisition device, the first signal output terminal of the controller is electrically connected to the signal input terminal of the second telescopic power source 414, and the second signal output terminal of the controller is electrically connected to the signal input terminal of the third telescopic power source 423.

[0119] The image is acquired by the image contour acquisition device 501 and the center point of the soil sample 203 to be divided is obtained. The second telescopic power source 414 and the third telescopic power source 423 are started by the controller, thereby driving the scraper to move back and forth and left and right, so that the rotation axis of the scraper coincides with the center point of the soil sample 203 to be divided, which makes it easier to flatten the soil sample 203 to be divided.

[0120] In this embodiment, please refer to Figures 1 to 7The sampling device further includes a gathering unit for re-gathering the soil sample 203 that has been flattened on the flexible film 202. The gathering unit includes at least three gathering components, and the at least three gathering components are arranged in a circular array at equal angles around the center line of the flexible film 202.

[0121] The number of gathering components here is three or four. When there are three, the three connection points of the steel wire 602 and the flexible film 202 are connected to each other to form an equilateral triangle. When there are four, the four connection points of the steel wire 602 and the flexible film 202 are connected to each other to form a square.

[0122] Each of the gathering components includes a second rotational power source 601, a steel wire 602, a winding reel 603, a sixth telescopic power source 604, and a sleeve 605;

[0123] The sixth telescopic power source 604 is fixedly installed inside the housing 101. The telescopic direction of the sixth telescopic power source 604 is perpendicular to the lifting direction of the scraper. The sleeve 605 is fixedly installed at the telescopic end of the sixth telescopic power source 604.

[0124] The sixth telescopic power source 604 is not limited here. It provides telescopic power for the sleeve 605. It can be an electric telescopic rod, a hydraulic cylinder, or a pneumatic cylinder.

[0125] The second rotational power source 601 is fixedly installed inside the housing 101, the winding reel 603 is fixedly installed on the rotational power output end of the second rotational power source 601, one end of the steel wire 602 is fixedly connected to the winding reel 603, and the other end of the steel wire 602 passes through the sleeve 605 and is detachably connected to the flexible film 202.

[0126] One embodiment of the connection between the steel wire 602 and the flexible film 202 is that a through hole is made in the flexible film 202, and the end of the steel wire 602 passes through the through hole and is tied in a knot in the middle of the steel wire 602; another embodiment is that a first magnet is fixedly installed on the steel wire 602, and a second magnet is fixedly installed on the flexible film 202, with the first magnet and the second magnet magnetically attracted to each other; a further embodiment is that the connection between the steel wire 602 and the flexible film 202 is detached by a snap fastener.

[0127] The second rotational power source 601 is an electric motor, which can directly drive the take-up reel 603 to rotate; or it can drive the take-up reel 603 to rotate through a gear set (a rotating shaft is fixedly installed on the take-up reel 603, the rotating shaft is rotatably installed in the housing 101, and the rotating shaft is transmitted to the motor output shaft through a gear set); or it can drive the take-up reel 603 to rotate through a belt (a rotating shaft is fixedly installed on the take-up reel 603, the rotating shaft is rotatably installed in the housing 101, and the rotating shaft is transmitted to the motor output shaft through a belt).

[0128] When it is necessary to re-aggregate the soil on the flexible film 202, the sixth telescopic power source 604 is first activated, driving the sleeve 605 to move above the soil sample. Then, the second rotational power source 601 is activated, winding the steel wire 602 onto the turntable, thereby lifting one corner of the flexible film 202. By performing the above operations on different gathering components in sequence, one cycle of the gathering unit is completed. By performing the above operations in multiple cycles, most of the soil samples can be re-piled into a triangular pyramid shape (when there are three gathering components) or a square pyramid shape (when there are four gathering components), realizing the re-aggregation of the soil samples and facilitating multiple quartering and discarding processes. At the same time, since the soil sample to be quartered is a mixture of soil from multiple sampling points, its weight will fluctuate depending on the number of sampling points. The final weight of the soil sample obtained by quartering will have certain requirements. Therefore, the number of times the quartering sample is discarded will be different for mixed soils of different weights.

[0129] In this embodiment, pressure sensors can also be installed between the telescopic ends of each sleeve 605 and the sixth telescopic power source 604. When multiple second rotational power sources 601 are started simultaneously, they drive the turntable to rotate, thereby causing the steel wire 602 to retract simultaneously, thereby lifting the flexible film 202 until it is separated from the support plate 201. The amount of soil sample on the flexible film 202 can be measured by the various pressure sensors, thereby determining the number of times the quartering method sample rejection needs to be performed.

[0130] Please see Figures 1 to 7 A sampling method for detecting microplastics in farmland soil, comprising:

[0131] The pressing steps for the flexible film 202 are as follows: the fourth telescopic power source 402 is activated to move the pressing block 401 above the flexible film 202, and the fifth telescopic power source 403 is activated to lower the pressing block 401 and press the flexible film 202.

[0132] Soil leveling steps: Start the lifting power source 321 to drive the scraper to descend, start the first rotation power source 312 to drive the rotating plate 311 to rotate, thereby driving the scraper to rotate while descending. When the scraper comes into contact with the soil sample 203 to be separated, the rotating scraper will level the part of the soil sample that is in contact with the scraper. The scraper continues to descend to level the entire soil sample 203 to be separated.

[0133] Soil four-part division process: After the soil sample 203 is flattened, the outer contour of the flattened soil sample is captured by the image contour acquisition device 501. The center point is analyzed by the controller, and the second telescopic power source 414 and the third telescopic power source 423 are activated to drive the scraper to move above the center point of the flattened soil sample to achieve the positioning of the scraper. The scraper descends and inserts into the flattened soil sample 203. The second telescopic power source 414 and the third telescopic power source 423 are activated in sequence, so that the scraper moves left and right and back and forth in sequence, thereby dividing the flattened soil sample into four parts.

[0134] Soil disposal steps: Activate the second telescopic power source 414 and the third telescopic power source 423 to drive the scraper to move to one side of one of the soil samples and push the soil sample out of the support plate 201, thereby realizing the disposal of the soil sample.

[0135] Soil re-aggregation steps: The second rotational power source 601 of different gathering components is activated in sequence to wind the steel wire 602 onto the winding reel 603, thereby lifting the flexible film 202 in sequence and re-aggregating the flattened soil sample into a cone shape.

[0136] The above embodiments are merely illustrative of the principles and effects of the present invention and are not intended to limit the invention. Any person skilled in the art can modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by those skilled in the art without departing from the spirit and technical concept disclosed in the present invention should still be covered by the claims of the present invention.

Claims

1. A sampling device for detecting microplastics in farmland soil, characterized in that, The sampling device includes: a housing, on which a soil sample inlet is provided; A soil sample support unit, the soil support unit comprising a support plate and a flexible film; The support plate is fixed inside the box, and there is a gap between the support plate and the box. The flexible film is placed on the transparent support plate, and the soil samples to be separated are stacked in a cone shape on the flexible film. A soil sample leveling unit, comprising a scraper, a rotating assembly, and an up-and-down lifting assembly; The scraper is installed inside the box. The rotating component drives the scraper to rotate, and the lifting component drives the scraper to rise and fall. The direction of the rotation axis of the scraper is parallel to the direction of the lifting and falling of the scraper, and the rotation axis of the scraper is perpendicular to the upper end face of the support plate. The scraper rotates and descends to flatten the soil sample to be separated. A soil sample division unit, comprising several compaction blocks, a front-to-back moving component, and a left-to-right moving component; Several of the aforementioned pressing blocks are arranged in a lifting manner inside the box. The pressing blocks are used to press the flexible film onto the support plate. The front-back moving component drives the scraper to move back and forth, and the left-right moving component drives the scraper to move left and right. The front-back moving direction, the left-right moving direction, and the up-down moving direction of the scraper are perpendicular to each other. The forward and backward moving assembly includes a sliding plate, a first slider, a first slide rod, and a second telescopic power source; The first slider is slidably mounted on the front wall / rear wall of the housing; The first slide rod is fixedly installed on the first slider. The axis of the first slide rod is perpendicular to the front wall of the box. The direction of the axis of the first slide rod is perpendicular to the sliding direction of the first slider. The sliding plate is slidably connected to the first slide rod. The second telescopic power source is fixedly installed on the first slider, and the telescopic end of the second telescopic power source is fixedly connected to the sliding plate; A rotating plate is rotatably mounted on the lower end face of the sliding plate; The left and right moving component includes a second slider, a second slide bar, and a third telescopic power source; The second slider is slidably mounted on the left wall / right wall of the box, and the sliding direction of the second slider is parallel to the axial direction of the first slider. The second slide rod is fixedly installed on the first slider, the axis of the second slide rod is parallel to the sliding direction of the first slider, and the second slide rod is slidably connected to the sliding plate; The third telescopic power source is fixedly installed on the second slider, and the telescopic end of the third telescopic power source is fixedly connected to the sliding plate. The sliding direction of the second slider is parallel to the axial direction of the first slider.

2. The sampling device for detecting microplastics in farmland soil according to claim 1, characterized in that, The scraper includes a main scraper, a through groove, a first auxiliary scraper, a second auxiliary scraper, and a telescopic power module; The main scraper has a through groove along its length. A first auxiliary scraper and a second auxiliary scraper are slidably installed in the through groove along its length. The first auxiliary scraper and the second auxiliary scraper slide in opposite directions along the length of the through groove and can extend out of the main scraper. The telescopic power module is fixedly installed on the main scraper. The telescopic power module includes two telescopic ends. One of the telescopic ends of the telescopic power module is fixedly connected to the first auxiliary scraper and drives the first auxiliary scraper to slide. The other telescopic end of the telescopic power module is fixedly connected to the second auxiliary scraper and drives the second auxiliary scraper to slide. The rotating assembly drives the main scraper to rotate.

3. The sampling device for detecting microplastics in farmland soil according to claim 1, characterized in that, The rotating assembly includes a rotating plate and a first rotational power source; The rotating plate is rotatably installed inside the box, and the rotation axis of the rotating plate is perpendicular to the upper end face of the support plate. The first rotation power source drives the rotating plate to rotate. The rotating plate rotates, causing the scraper to rotate.

4. The sampling device for detecting microplastics in farmland soil according to claim 3, characterized in that, The lifting assembly includes a lifting power source; One end of the lifting power source is fixedly installed on the rotating plate, and the other end of the lifting power source is fixedly connected to the scraper. The lifting power source drives the scraper to move up and down.

5. A sampling device for detecting microplastics in farmland soil according to claim 1, characterized in that, The soil sample division unit also includes several pressing power components that drive several pressing blocks to press the flexible film. The several pressing power components are arranged in a circular array around the center line of the flexible film. Each of the several pressing power components includes a fourth telescopic power source and a fifth telescopic power source. The fourth telescopic power source is fixedly installed on the inner wall of the box, and the telescopic direction of the fourth telescopic power source is parallel to the upper end face of the support plate. The fifth telescopic power source is fixedly installed at the telescopic end of the fourth telescopic power source. The telescopic direction of the fifth telescopic power source is perpendicular to the upper surface of the support plate. The pressing block is fixedly installed at the telescopic end of the fifth telescopic power source. The pressing block descends and presses the flexible film onto the support plate.

6. The sampling device for detecting microplastics in farmland soil according to claim 1, characterized in that, The sampling device also includes a positioning unit for measuring the center point of the soil sample to be divided, the positioning unit including a controller and an image contour acquisition device; The image contour collector is fixed above the flexible film, and the data acquisition end of the image contour collector faces the soil sample to be separated. The image contour collector acquires the outer contour data of the soil sample to be separated. The signal input terminal of the controller is electrically connected to the signal output terminal of the image acquisition device, the first signal output terminal of the controller is electrically connected to the signal input terminal of the second telescopic power source, and the second signal output terminal of the controller is electrically connected to the signal input terminal of the third telescopic power source.

7. A sampling device for detecting microplastics in farmland soil according to claim 1, characterized in that, The sampling device also includes a gathering unit for re-gathering the soil sample to be separated after it has been spread out on the flexible film. The gathering unit includes at least three gathering components, and the at least three gathering components are arranged in a circular array at equal angles around the center line of the flexible film. Each of the gathering components includes a second rotational power source, a steel wire, a winding reel, a sixth telescopic power source, and a sleeve. The sixth telescopic power source is fixedly installed inside the box, and the telescopic direction of the sixth telescopic power source is perpendicular to the lifting direction of the scraper. The sleeve is fixedly installed at the telescopic end of the sixth telescopic power source. The second rotational power source is fixedly installed inside the housing, and the winding reel is fixedly installed on the rotational power output end of the second rotational power source. One end of the steel wire is fixedly connected to the winding reel, and the other end of the steel wire passes through the sleeve and is detachably connected to the flexible film.

8. A sampling method based on the sampling device for detecting microplastics in farmland soil according to any one of claims 1-7, characterized in that, The sampling method includes: Flexible film pressing steps: Activate the fourth telescopic power source to move the pressing block above the flexible film, and activate the fifth telescopic power source to lower the pressing block and press the flexible film. Soil leveling steps: Start the lifting power source to drive the scraper to descend, start the first rotation power source to drive the rotating plate to rotate, thereby driving the scraper to rotate while descending. When the scraper comes into contact with the soil sample to be separated, the rotating scraper will level the part of the soil sample that is in contact with the scraper. The scraper continues to descend to level the entire soil sample to be separated. Soil four-part division process: After the soil sample to be divided is flattened, the outer contour of the flattened soil sample is captured by an image contour acquisition device. The center point is analyzed by the controller. The second and third telescopic power sources are activated to drive the scraper to move above the center point of the flattened soil sample to achieve the positioning of the scraper. The scraper descends and inserts into the flattened soil sample to be divided. The second and third telescopic power sources are activated in sequence to make the scraper move left and right and back and forth in sequence, thereby dividing the flattened soil sample into four parts. Soil disposal steps: Activate the second and third telescopic power sources to move the scraper to one side of one of the soil samples and push the soil sample out of the support plate, thereby discarding the soil sample. Soil re-aggregation steps: The second rotational power source of different re-aggregation components is activated in sequence to wind the steel wire onto the winding reel, thereby lifting the flexible film in sequence and re-aggregating the flattened soil sample into a cone shape.

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