A stratified sampling device for surface water environmental monitoring

Abstract

This utility model relates to the field of surface water sampling technology and discloses a stratified sampling device for surface water environmental testing. The device includes a sampling box with a rectangular groove at its front end. Multiple sampling cylinders arranged in a longitudinal array are fixedly installed inside the rectangular groove. A sealing ring is fixedly installed at the upper end of each sampling cylinder. The sampling cylinder is characterized by further including: a depth adjustment mechanism installed at the rear end of the sampling box to control the overall depth of the sampling box during use; and a sealing control mechanism installed inside the sampling box. After sampling, the waterproof motor reverses to drive the third threaded rod to rotate, causing the sealing cover to quickly descend and tightly fit against the sealing ring at the upper end of the sampling cylinder. This directly blocks the flow of water between the sampling cylinder and the external water body, avoiding the exchange path of water bodies from different water layers during the lifting process, completely preventing sample contamination, and ensuring the accuracy of the test data.

Description

Technical Field

[0001] This utility model relates to the field of surface water sampling technology, and in particular to a stratified sampling device for surface water environmental monitoring. Background Technology

[0002] Surface water, as one of the important sources of drinking water for human life, often exists in liquid and solid physical forms, mainly in the form of rivers, lakes, wetlands, and glaciers. Surface water is widely exposed to the external environment and faces pollution from various human activities. In order to ensure the safety of drinking water and protect water resources, it is necessary to conduct regular surface water environmental monitoring, pay attention to surface water quality, and ensure that the protection of surface water resources is preventive and controllable.

[0003] Patent CN214067126U discloses a user-friendly surface water environmental monitoring device. This device utilizes a pipe, lifting mechanism, housing, mounting base, lifting motor, first flat gear, first transmission rod, second transmission rod, first bevel gear, roller, cable, guide wheel, sampling bucket, adjusting mechanism, base, slide rail, lead screw, crank, and water quality analyzer to perform layered sampling and testing of surface water. The adjusting mechanism adjusts the position of the roller. Turning the crank causes the base to slide along the inner side of the slide rail, engaging the first bevel gear and second transmission rod to activate the lifting motor and release the sampling bucket. The sampling bucket enters the water through the pipe. Upon reaching different sampling depths, the lifting motor is turned off. Turning the crank engages the first bevel gear and second transmission rod, restarting the lifting motor to release the sampling bucket. This process releases all sampling buckets, allowing for sampling and testing of surface water at different depths. This obtains three-dimensional distribution data of pollutants in the surface water, leading to accurate surface water environmental monitoring results.

[0004] The device involves directly placing the sampling bucket into the water in an open state and then retrieving it after reaching the target depth. However, as the sampling bucket is lifted from the target depth to the surface, it passes through water layers of different depths, causing slight exchange between the water inside the bucket and the water it passes through, which can lead to sample contamination. Utility Model Content

[0005] In order to overcome the above-mentioned defects of the prior art, this utility model provides a stratified sampling device for surface water environmental monitoring, so as to solve the problem that the water in the sampling bucket is exchanged with the water body along the way when the sampling bucket is moved upward after sampling, resulting in sample contamination.

[0006] This utility model provides a stratified sampling device for surface water environmental monitoring, comprising a sampling box, a rectangular groove at the front end of the sampling box, and multiple sampling cylinders arranged in a longitudinal array fixedly installed inside the rectangular groove. A sealing ring is fixedly installed at the upper end of each sampling cylinder. The sampling cylinder is characterized by further comprising:

[0007] A depth adjustment mechanism is installed at the rear end of the sampling box, and the depth adjustment mechanism is used to control the overall depth of the sampling box during use;

[0008] A sealing control mechanism is installed inside the sampling box and is used to seal multiple sampling tubes after sampling.

[0009] A floating mechanism, which is mounted on a depth adjustment mechanism, is used to control the sampling box to float on the water surface.

[0010] Preferably, the depth adjustment mechanism includes a fixed plate and a first threaded rod. The fixed plate is installed at the rear end of the sampling box by a fixed connection. The first threaded rod is installed at the upper end of the fixed plate by a threaded connection. A limiting platform is rotatably installed at the upper outer end of the first threaded rod. A bearing is fixedly embedded at the rear end of the limiting platform. The first threaded rod is fixedly inserted into the bearing. A rotating block is fixedly installed at the upper end of the first threaded rod.

[0011] Preferably, the sealing control assembly includes a rotating component and multiple sealing covers. The rotating component is installed inside the sampling box via a rotatable connection and is located in the middle of a rectangular groove. A waterproof motor is fixedly installed at the front upper part of the sampling box, and the output end of the waterproof motor is connected to the rotating component. The multiple sealing covers are located above multiple sampling cylinders, and the shape of the sealing covers is adapted to the shape of the sampling cylinders. The rotating component penetrates through the sealing covers and is used to drive the multiple sealing covers to lift and lower synchronously to realize the opening and closing of the sealing covers.

[0012] Preferably, the rotating component includes a second threaded rod and a third threaded rod. The second threaded rod is installed inside the front end of the limiting platform via a rotatable connection and is fixedly connected to the output end of the waterproof motor. A retaining ring is fixedly installed on the lower outer end of the second threaded rod. The third threaded rod is installed in the middle of the sampling box via a rotatable connection and is rotatably connected to multiple sampling cylinders. The third threaded rod is threadedly connected to multiple sealing caps. A telescopic part is installed between the third threaded rod and the second threaded rod. The telescopic part includes a telescopic rod and multiple limiting strips. A circular insertion hole is provided at the upper inner end of the third threaded rod. A strip groove is provided at each of the four ends of the circular insertion hole. The telescopic rod is fixedly installed at the middle of the lower end of the second threaded rod. The multiple limiting strips are fixedly installed at the four outer ends of the second threaded rod. The telescopic rod is inserted into the circular insertion hole, and the limiting strips are inserted into the strip grooves. The telescopic rod and the limiting strips are slidably connected to the third threaded rod through the circular insertion hole and the strip groove, respectively.

[0013] Preferably, the floating mechanism includes two connecting bars and a lifting ring. The lower ends of both sides of the limiting platform are provided with mounting grooves, which are located at both ends of the lifting ring. The connecting bars are installed in the mounting grooves via a rotatable connection. A float plate is fixedly embedded in the lower inner side of the connecting bar. A first limiting seat is fixedly installed in the upper inner side of the connecting bar. The lifting ring is installed in the lower outer side of the second threaded rod via a threaded installation. Second limiting seats are fixedly installed in both sides of the lifting ring. A connecting rod is rotatably installed on the second limiting seat, and the end of the connecting rod away from the lifting ring is rotatably connected to the first limiting seat.

[0014] Preferably, each of the sampling tubes has an external threaded connecting tube at the center of its front end. A threaded mounting cap is installed on the outer thread of the external threaded connecting tube, and a rubber diaphragm is provided at the front end of the inner threaded mounting cap. The rubber diaphragm and the threaded mounting cap are integrally formed.

[0015] Compared with the prior art, the beneficial effects of this utility model are:

[0016] 1. After sampling is completed, the waterproof motor reverses to drive the third threaded rod to rotate, causing the sealing cover to descend rapidly and fit tightly with the sealing ring at the top of the sampling tube. This directly blocks the flow between the sampling tube and the external water body, avoids the exchange path of water bodies in different water layers during the lifting process, completely avoids sample contamination, and ensures the accuracy of the test data.

[0017] 2. This utility model achieves efficient and accurate sampling through the linkage of multiple mechanisms. In the depth adjustment mechanism, the rotating block drives the first threaded rod to rotate. With the help of its threaded engagement with the fixed plate and the bearing connection of the limiting stage, the height of the sampling box can be precisely adjusted, so that the sampling tubes in the longitudinal array in the rectangular groove are accurately aligned with different target water layers. The sealing control mechanism realizes the synchronous rotation of the second and third threaded rods through the sliding linkage of the telescopic part, driving multiple sealing covers to open and close synchronously, and multi-layer water sample collection can be completed in one operation. The floating mechanism enables the float to be raised and lowered synchronously with the sealing action through the transmission of the lifting ring and the connecting rod, which not only ensures the stable positioning of the device during sampling, but also does not affect the depth adjustment. The three mechanisms work together to greatly reduce the operational complexity of stratified sampling and improve sampling efficiency and depth adaptation flexibility. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the overall main structure of this utility model;

[0019] Figure 2 This utility model Figure 1 Enlarged structural diagram at point A in the middle;

[0020] Figure 3 This utility model Figure 1 Enlarged structural diagram at point B;

[0021] Figure 4 This is a schematic diagram of the storage state structure of the floating mechanism of this utility model;

[0022] Figure 5 This is a schematic diagram of the floating mechanism of this utility model in use.

[0023] Numbering on the map:

[0024] 1. Sampling box; 11. Rectangular groove; 2. Depth adjustment mechanism; 21. Fixing plate; 22. First threaded rod; 23. Limiting platform; 24. Rotating block; 3. Sampling cylinder; 31. Sealing ring; 32. Threaded mounting cover; 321. Rubber diaphragm; 4. Sealing control mechanism; 41. Rotating component; 411. Second threaded rod; 4111. Retaining ring; 412. Telescopic part; 4121. Telescopic rod; 4122. Limiting strip; 413. Third threaded rod; 42. Sealing cover; 43. Waterproof motor; 5. Floating mechanism; 51. Connecting strip; 511. First limiting seat; 52. Float plate; 53. Lifting ring; 531. Second limiting seat; 54. Connecting rod. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0026] like Figure 1-5 As shown, this utility model has the following three specific embodiments.

[0027] Example 1

[0028] A stratified sampling device for surface water environmental monitoring includes a sampling box 1, a rectangular groove 11 at the front end of the sampling box 1, and multiple sampling cylinders 3 arranged in a longitudinal array fixedly installed inside the rectangular groove 11. A sealing ring 31 is fixedly installed at the upper end of each sampling cylinder 3. The sampling cylinder 3 is characterized by further comprising:

[0029] Depth adjustment mechanism 2 is installed at the rear end of sampling box 1 and is used to control the overall depth of sampling box 1 during use.

[0030] The sealing control mechanism 4 is installed inside the sampling box 1 and is used to seal the multiple sampling tubes 3 after sampling.

[0031] The floating mechanism 5 is installed on the depth adjustment mechanism 2 and is used to control the sampling box 1 to float on the water surface.

[0032] Multiple sampling tubes 3 are provided with external threaded connecting pipes at the front middle. Threaded mounting caps 32 are installed on the outer threads of the external threaded connecting pipes. A rubber diaphragm 321 is provided at the front end of the threaded mounting cap 32. The rubber diaphragm 321 and the threaded mounting cap 32 are integrally molded.

[0033] In this embodiment, as Figures 1-5 As shown, before use, check the integrity of the device. The external threaded connecting pipe at the front end of the sampling tube 3 and the threaded mounting cap 32 are kept tightened, and the rubber diaphragm 321 is in a closed state to ensure initial sealing. After the device is transported to the sampling water area, the target sampling depth range is preset by the depth adjustment mechanism 2 at the rear end of the sampling box 1 to ensure that the multiple longitudinally arrayed sampling tubes 3 can correspond to different water layers. After the device is positioned, the sealing structure of the sampling tube 3 is opened by the sealing control mechanism 4 to allow water at the target depth to enter the sampling tube 3. At the same time, the device is made to float steadily on the water surface by the floating mechanism 5 on the sampling box 1. After sampling is completed, the sealing control mechanism 4 immediately seals the multiple sampling tubes 3. Finally, the sampling box 1 is lifted to the water surface by the depth adjustment mechanism 2 to complete the basic stratified sampling operation.

[0034] Example 2

[0035] The difference from Embodiment 1 is that this embodiment discloses a depth adjustment mechanism 2 and a sealing control mechanism 4:

[0036] The depth adjustment mechanism 2 includes a fixed plate 21 and a first threaded rod 22. The fixed plate 21 is installed at the rear end of the sampling box 1 by a fixed connection. The first threaded rod 22 is installed at the upper end of the fixed plate 21 by a threaded connection. A limiting platform 23 is rotatably installed at the upper outer end of the first threaded rod 22. A bearing is fixedly embedded at the rear end of the limiting platform 23. The first threaded rod 22 is fixedly inserted into the bearing. A rotating block 24 is fixedly installed at the upper end of the first threaded rod 22.

[0037] The sealing control assembly 4 includes a rotating component 41 and multiple sealing covers 42. The rotating component 41 is installed inside the sampling box 1 by a rotating connection and is located in the middle of the rectangular groove 11. A waterproof motor 43 is fixedly installed at the front of the upper end of the sampling box 1. The output end of the waterproof motor 43 is connected to the rotating component 41. The multiple sealing covers 42 are all located above the multiple sampling cylinders 3, and the shape of the sealing covers 42 is adapted to the shape of the sampling cylinders 3. The rotating component 41 passes through the sealing cover 42 and is used to drive the multiple sealing covers 42 to lift and lower synchronously to realize the opening and closing of the sealing covers 42.

[0038] The rotating component 41 includes a second threaded rod 411 and a third threaded rod 413. The second threaded rod 411 is rotatably connected to the front end of the limiting platform 23 and is fixedly connected to the output end of the waterproof motor 43. A retaining ring 4111 is fixedly installed on the lower outer side of the second threaded rod 411. The third threaded rod 413 is rotatably connected to the middle of the sampling box 1 and is rotatably connected to multiple sampling cylinders 3. The third threaded rod 413 is threadedly connected to multiple sealing caps 42. A telescopic part 412 is installed between the third threaded rod 413 and the second threaded rod 411. The telescopic part 412 includes a telescopic rod 4121 and multiple limiting strips 4122. The upper end of the third threaded rod 413 is provided with a circular insertion hole, and each of the four ends of the circular insertion hole is provided with a strip groove. The telescopic rod 4121 is installed in the middle of the lower end of the second threaded rod 411 by a fixed connection. The multiple limiting strips 4122 are respectively installed in the four ends of the outer side of the second threaded rod 411 by a fixed connection. The telescopic rod 4121 is inserted into the circular insertion hole, and the limiting strips 4122 are inserted into the strip grooves. The telescopic rod 4121 and the limiting strips 4122 are slidably connected to the third threaded rod 413 through the circular insertion hole and the strip groove, respectively.

[0039] In this embodiment, as Figures 1-3 As shown, before sampling, the rotating block 24 at the upper end of the first threaded rod 22 is rotated. Because the first threaded rod 22 is threadedly connected to the fixed plate 21 at the rear end of the sampling box 1, and the limiting platform 23 is rotatably connected to the first threaded rod 22 through a bearing, the rotation of the first threaded rod 22 drives the limiting platform 23 to rise and fall, thereby adjusting the initial height of the entire sampling box 1. After reaching the sampling water area, the waterproof motor 43 at the front of the upper end of the sampling box 1 is started. Its output end drives the second threaded rod 411 to rotate. The second threaded rod 411 is inserted into the circular insertion hole of the third threaded rod 413 through the telescopic rod 4121 at the lower end, and the limiting strips 4122 at the four outer ends are embedded in the strip groove of the third threaded rod 413. The sliding linkage of the telescopic part 412 drives the third threaded rod 413 to rotate synchronously. Since the third threaded rod 413 is threadedly connected to multiple sealing caps 42 and rotatably connected to the sampling cylinder 3, the rotation of the third threaded rod 413 drives the sealing caps 42 to rise and fall along their axial direction. When the sealing caps 42 rise, they open the sampling cylinder 3, allowing water to enter for sampling. After sampling, the waterproof motor 43 reverses, and the sealing caps 42 descend to fit against the sealing ring 31 at the upper end of the sampling cylinder 3, achieving a seal. At the same time, the depth of the sampling box 1 can be changed by rotating the rotating block 24 to adapt to the sampling needs of different water layers.

[0040] Example 3

[0041] The difference from Embodiment 2 is that this embodiment discloses a floating mechanism 5:

[0042] The floating mechanism 5 includes two connecting bars 51 and a lifting ring 53. The lower ends of both sides of the limiting platform 23 are provided with mounting grooves, which are located at both ends of the lifting ring 53. The connecting bars 51 are installed in the mounting grooves via a rotatable connection. A float plate 52 is fixedly embedded in the lower inner side of the connecting bar 51. A first limiting seat 511 is fixedly installed on the upper inner side of the connecting bar 51. The lifting ring 53 is installed on the lower outer side of the second threaded rod 411 via a threaded installation. Second limiting seats 531 are fixedly installed on both sides of the lifting ring 53. A connecting rod 54 is rotatably installed on the second limiting seat 531, with the end of the connecting rod 54 away from the lifting ring 53 rotatably connected to the first limiting seat 511.

[0043] In this embodiment, as Figures 3-5 As shown, when the waterproof motor 43 drives the second threaded rod 411 to rotate and control the lifting and lowering of the sealing cover 42, the lifting ring 53 is threadedly connected to the lower outer end of the second threaded rod 411. The rotation of the second threaded rod 411 drives the lifting ring 53 to move up and down, thus opening and closing the floating mechanism 5. When the rotating part 41 rotates as a whole, driving multiple sealing covers 42 and lifting rings 53 to move down, the sampling tube 3 achieves sealing, and the two floats 52 rotate inward to retract. When the rotating part 41 rotates in the opposite direction, the sealing cover 42 moves up and opens, and the lifting ring 53 moves up synchronously. Under the support of the connecting rod 54, it rotates ninety degrees to open, and then the floats 52 float on the water surface to help the sampling box 1 maintain a certain height for water sampling.

[0044] The working principle of this utility model is as follows: Before use, check the integrity of the device to ensure that the external threaded connecting pipe at the front end of the sampling tube 3 is tightened with the threaded mounting cap 32 and the rubber diaphragm 321 is in a closed state to ensure initial sealing. Before sampling, the sampling depth is preset by the depth adjustment mechanism 2. The operator rotates the rotating block 24 at the upper end of the first threaded rod 22. Since the first threaded rod 22 is threadedly connected to the fixing plate 21 at the rear end of the sampling box 1, and the limiting platform 23 is rotatably connected to the first threaded rod 22 through the bearing, the rotation of the first threaded rod 22 drives the limiting platform 23 to rise and fall, thereby adjusting the overall initial height of the sampling box 1 so that the sampling tubes 3 arranged longitudinally in the rectangular groove 11 correspond to the target water layer. Upon reaching the sampling area, the waterproof motor 43 at the front of the upper end of the sampling box 1 is activated. Its output end drives the second threaded rod 411 to rotate. On one hand, the second threaded rod 411 is inserted into the circular insertion hole of the third threaded rod 413 through the telescopic rod 4121 of the lower telescopic part 412, and the outer limiting strip 4122 is embedded in the strip groove of the third threaded rod 413. Through sliding linkage, the third threaded rod 413 is driven to rotate synchronously. Since the third threaded rod 413 is threadedly connected to multiple sealing covers 42 and rotatably connected to the sampling cylinder 3, its rotation drives the sealing covers 42 to rise and fall axially. When the sampling tube 3 is opened, the water enters and the sampling is completed. On the other hand, because the lifting ring 53 is threaded to the lower outer end of the second threaded rod 411, the rotation of the second threaded rod 411 drives the lifting ring 53 to move synchronously. When the rotating part 41 rotates in the opposite direction to make the sealing cover 42 move up and open the sampling tube 3, the lifting ring 53 moves up synchronously. The second limit seats 531 on both sides push the first limit seat 511 on the inner side of the connecting strip 51 through the connecting rod 54, so that the connecting strip 51 rotates around the rotation axis of the mounting groove on both sides of the limit platform 23. The float 52 unfolds and floats on the water surface, helping the sampling box 1 to maintain a stable height.

[0045] After sampling, the waterproof motor 43 reverses, and the third threaded rod 413 drives the sealing cover 42 to descend and fit against the sealing ring 31 at the upper end of the sampling cylinder 3 to achieve a seal. At the same time, the lifting ring 53 moves down, and the connecting rod 54 pulls the connecting strip 51 to retract the float 52 inward. The staff can use a syringe to take samples, inserting the needle into the rubber diaphragm to draw out the water in the sampling cylinder 3, which can effectively prevent water contamination. The threaded mounting cover 32 and the rubber diaphragm 321 can be rotated and replaced. If it is necessary to collect water samples at different depths, the rotating block 24 can be rotated again to adjust the first threaded rod 22 to change the depth of the sampling box 1. The above sampling and sealing steps are repeated, and finally the sampling box 1 is raised to the water surface by the depth adjustment mechanism 2.

[0046] Although the disclosure is as stated above, the scope of protection of this disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of this disclosure, and all such changes and modifications will fall within the protection scope of this utility model.

Claims

1. A stratified sampling device for surface water environmental monitoring, comprising a sampling box (1), wherein a rectangular groove (11) is provided at the front end of the sampling box (1), and a plurality of sampling tubes (3) arranged in a longitudinal array are fixedly installed inside the rectangular groove (11), wherein a sealing ring (31) is fixedly installed at the upper end of the sampling tubes (3), wherein the sampling tubes (3) are characterized in that, Also includes: A depth adjustment mechanism (2) is installed at the rear end of the sampling box (1) and is used to control the overall depth of the sampling box (1) during use. A sealing control mechanism (4) is installed inside the sampling box (1) and is used to seal multiple sampling tubes (3) after sampling. A floating mechanism (5) is installed on a depth adjustment mechanism (2) and is used to control the sampling box (1) to float on the water surface.

2. The layered sampling device for detecting surface water environment according to claim 1, characterized in that, The depth adjustment mechanism (2) includes a fixed plate (21) and a first threaded rod (22). The fixed plate (21) is installed at the rear end of the sampling box (1) by a fixed connection. The first threaded rod (22) is installed at the upper end of the fixed plate (21) by a threaded connection. A limiting platform (23) is rotatably installed at the upper end of the outer side of the first threaded rod (22). A bearing is fixedly embedded at the rear end of the limiting platform (23). The first threaded rod (22) is fixedly inserted into the bearing. A rotating block (24) is fixedly installed at the upper end of the first threaded rod (22).

3. The layered sampling device for detecting surface water environment according to claim 1, characterized in that, The sealing control mechanism (4) includes a rotating part (41) and multiple sealing covers (42). The rotating part (41) is installed inside the sampling box (1) by a rotating connection and is located in the middle of the rectangular groove (11). A waterproof motor (43) is fixedly installed at the front of the upper end of the sampling box (1). The output end of the waterproof motor (43) is connected to the rotating part (41). Multiple sealing covers (42) are located above multiple sampling cylinders (3) and the shape of the sealing covers (42) is adapted to the sampling cylinders (3). The rotating part (41) penetrates the sealing cover (42) and is used to drive multiple sealing covers (42) to rise and fall synchronously to realize the opening and closing of the sealing cover (42).

4. The layered sampling device for detecting surface water environment according to claim 3, characterized in that, The rotating component (41) includes a second threaded rod (411) and a third threaded rod (413). The second threaded rod (411) is installed inside the front end of the limiting platform (23) by a rotatable connection, and the second threaded rod (411) is fixedly connected to the output end of the waterproof motor (43). A retaining ring (4111) is fixedly installed on the lower outer side of the second threaded rod (411). The third threaded rod (413) is installed in the middle of the sampling box (1) by a rotatable connection, and the third threaded rod (413) is rotatably connected to multiple sampling cylinders (3). The third threaded rod (413) is threadedly connected to multiple sealing caps (42). A telescopic part (413) is installed between the third threaded rod (413) and the second threaded rod (411). 12) The telescopic part (412) includes a telescopic rod (4121) and multiple limiting strips (4122). The upper end of the third threaded rod (413) is provided with a circular insertion hole. The four ends of the circular insertion hole are provided with strip grooves. The telescopic rod (4121) is installed in the middle of the lower end of the second threaded rod (411) by a fixed connection. The multiple limiting strips (4122) are respectively installed in the four ends of the outer side of the second threaded rod (411) by a fixed connection. The telescopic rod (4121) is inserted into the circular insertion hole. The limiting strips (4122) are inserted into the strip grooves. The telescopic rod (4121) and the limiting strips (4122) are slidably connected to the third threaded rod (413) through the circular insertion hole and the strip groove, respectively.

5. The layered sampling device for detecting surface water environment according to claim 2, characterized in that, The floating mechanism (5) includes two connecting bars (51) and a lifting ring (53). The lower ends of both sides of the limiting platform (23) are provided with mounting grooves, and the mounting grooves are located at both ends of the lifting ring (53). The connecting bars (51) are installed in the mounting grooves by a rotating connection. A float plate (52) is fixedly embedded in the lower inner side of the connecting bar (51). A first limiting seat (511) is fixedly installed in the upper inner side of the connecting bar (51). The lifting ring (53) is installed in the lower outer side of the second threaded rod (411) by a threaded installation. A second limiting seat (531) is fixedly installed in both sides of the lifting ring (53). A connecting rod (54) is rotatably installed in the second limiting seat (531). The end of the connecting rod (54) away from the lifting ring (53) is rotatably connected to the first limiting seat (511).

6. The layered sampling device for detecting surface water environment according to claim 1, characterized in that, Each of the sampling tubes (3) has an external threaded connecting tube at the front center. A threaded mounting cap (32) is installed on the outer thread of the external threaded connecting tube. A rubber diaphragm (321) is installed at the front end of the threaded mounting cap (32). The rubber diaphragm (321) and the threaded mounting cap (32) are integrally formed.

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