Urban inverted siphon flexible articulated chain sampling device

By combining a support base and a flexible hinged chain structure with a drive roller and chain structure, the problems of spin, entanglement and wear of the sampling device in the inverted siphon are solved, enabling accurate sampling in complex pipelines and improving the reliability and accuracy of the sampling equipment.

CN122361008APending Publication Date: 2026-07-10ZIBO ECOLOGICAL ENVIRONMENT MONITORING CENT OF SHANDONG PROVINCE
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Patent Information

Application Number
CN202610654514.1
Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
Filing Date
2026-05-13
Publication Date
2026-07-10

AI Technical Summary

Technical Problem

Existing sampling and conveying devices suffer from problems such as spinning, turning, tangling, twisting, and wear in inverted siphons, leading to loss of control over the sampling equipment's posture, inability to accurately reach the target point, and slippage in humid environments, making it impossible to achieve accurate position feedback and depth control.

Method used

The system adopts a combination structure of support base, horizontal guide rail and flexible hinge chain. The drive mechanism achieves forced transmission through drive roller with radial positioning groove. The flexible hinge chain contains air delivery hose. The chain structure composed of pin and side plate provides axial constraint to ensure that the pneumatic sampling component moves smoothly in complex pipelines.

Benefits of technology

It enables smooth delivery in complex pipelines, avoids entanglement and wear of flexible pipelines, ensures precise control of sampling depth and position, and improves the reliability of sampling operations and system integration.

✦ Generated by Eureka AI based on patent content.

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Abstract

This invention discloses a flexible articulated chain sampling device for urban inverted siphons, belonging to the technical field of pipeline environmental sampling equipment. It includes a support base with horizontal guide rails, a drive mechanism with a drive roller having radial positioning grooves, a flexible articulated chain composed of pins and connecting side plates, a movable carriage carrying a pneumatic power source, and a pneumatic sampling assembly; a gas delivery hose passes through the flexible articulated chain. This invention achieves forced and precise transmission through the physical engagement of the drive roller and the chain pin, solving the problems of slippage and poor positioning accuracy of flexible conveying mechanisms in humid environments. By using the chain structure as a physical barrier to constrain the internal hose throughout its stroke, it solves the technical problems of easy entanglement, kinking, and wear of power pipelines in complex curved pipelines. Simultaneously, by utilizing the single-degree-of-freedom articulation characteristics and lateral rigidity of the chain, it solves the problems of spin and rotation during device movement, ensuring the stability of the sampling posture and the reliability of operation.
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Description

Technical Field

[0001] This invention belongs to the technical field of pipeline environmental sampling equipment, specifically relating to a flexible hinged chain sampling device for urban inverted siphons. Background Technology

[0002] Due to their unique concave structure, inverted siphons in urban drainage systems are prone to siltation and pollutant deposition at the bottom. Regular sampling and analysis of internal sediments is crucial for ensuring network efficiency and environmental monitoring. With the increasing automation of pipeline maintenance, using mechanized equipment for deep sampling within the pipes has become a mainstream industry trend. This type of equipment typically needs to pass through a long vertical pipe into a horizontal pipe, and a conveying mechanism delivers the sampling probe to a preset position, using an external power source to drive the end sampler to collect the material. However, the internal environment of an inverted siphon is complex, containing high humidity, high corrosion, and high concentrations of silt. Furthermore, the pipe's twists and turns place extremely high demands on the structural reliability, motion accuracy, and energy transmission safety of the conveying mechanism.

[0003] Existing sampling and delivery devices have revealed numerous technical shortcomings in practical applications. First, traditional flexible steel wire ropes or simple hoses lack sufficient mechanical rigidity. When traveling through complex, winding pipelines, they are prone to spinning or turning due to water flow disturbances or uneven force, leading to loss of control of the end sampler's posture and difficulty in accurately reaching the target point. Second, power pipelines (such as gas pipes and cables) are typically externally mounted or arranged in parallel. During long-distance transport and frequent chain folding and reversing, the hoses are prone to tangling, twisting, and severe mechanical wear against the pipeline wall, even causing power interruption. Furthermore, existing drive methods mostly rely on friction transmission, which is prone to slippage in wet and slippery pipeline environments, resulting in inaccurate sampling depth positioning and an inability to achieve precise position feedback and depth control. Summary of the Invention

[0004] In view of the shortcomings of the prior art described above, the purpose of this invention is to provide a flexible articulated chain sampling device for urban inverted siphons, which solves the problems of difficult sampling of inverted siphons and the spinning and rotation of sampling equipment during the process of travel in the prior art.

[0005] To achieve the above objectives, the present invention provides the following technical solution: The present invention includes a support base, a drive mechanism, a flexible hinge chain, a movable carriage, and a pneumatic sampling assembly; The rear end of the support base is vertically provided with a support rear plate, and two parallel horizontal guide rails extend forward along the horizontal direction from the support rear plate. The drive mechanism is located at the front end of the support base and includes two symmetrically arranged vertical brackets, a power drive shaft rotatably arranged between the vertical brackets, a motor for driving the power drive shaft to rotate, and a drive roller coaxially fixed to the middle of the power drive shaft; the outer surface of the drive roller is evenly provided with multiple radial positioning grooves. The flexible hinge chain is slidably disposed on the horizontal guide rail, including alternating first and second hinge pins, and a connecting side plate hinged between adjacent first and second hinge pins. The movable carriage is slidably mounted across the horizontal guide rail. A pneumatic power source is installed on the movable carriage, and the pneumatic power source is connected to a flexible air supply hose that passes through the body of the flexible hinge chain. The pneumatic sampling component is fixedly connected to the front end of the flexible hinge chain, and the pneumatic sampling component is connected to the gas delivery hose.

[0006] Optionally, the axial length of the first hinge pin is greater than the distance between the two horizontal guide rails, and both ends of the first hinge pin are mounted on the upper surface of the horizontal guide rails; the axial length of the second hinge pin is less than the distance between the two horizontal guide rails, and both ends of the second hinge pin hang below the horizontal guide rails; the flexible hinge chain body presents a folded and undulating state on the horizontal guide rails through the alternating support of the first hinge pin and the second hinge pin.

[0007] Optionally, the geometric center of both the first hinge pin and the second hinge pin is provided with a central through hole along the axial direction, and the air supply hose passes through the central through hole in sequence; the center of the circumferential surface of the drive roller is provided with an inwardly recessed avoidance ring groove, and the depth of the avoidance ring groove is greater than the depth of the radial positioning groove; when the flexible hinge chain rotates around the drive roller, the air supply hose is embedded in the avoidance ring groove.

[0008] Optionally, the lower side of the horizontal guide rail is provided with a plurality of vertical support rods arranged in a longitudinal linear array, and the two ends of the vertical support rods are fixedly connected to the horizontal guide rail and the support base, respectively; the end of the flexible hinge chain is provided with an end long pin, and each of the upper ends of the vertical bracket is fixed with a limiting block; the lateral distance between the two limiting blocks is greater than the length of the first hinge pin and less than the length of the end long pin.

[0009] Optionally, the pneumatic sampling assembly includes a sampling base and a buoyancy drive support structure; the sampling base includes a through channel penetrating the top and bottom surfaces; the interior of the sampling base also has a drive cylinder chamber and a rack guide chamber arranged in parallel; the buoyancy drive support structure includes a lower positioning ring, a support connecting plate, a guide column, an upper guide ring, a linkage pressure plate, and a flexible buoyancy bladder; the lower positioning ring is fixed to the upper periphery of the sampling base through the support connecting plate; the guide column is vertically fixed to the top surface of the sampling base; the linkage pressure plate is slidably sleeved on the guide column, and the upper guide ring is fixedly connected to the outer periphery of the linkage pressure plate; the flexible buoyancy bladder is connected between the lower positioning ring and the upper guide ring.

[0010] Optionally, the pneumatic sampling assembly further includes a synchronous transmission mechanism; the synchronous transmission mechanism includes two parallel synchronous transmission shafts, which are rotatably mounted across the through channel; meshing transmission gears are coaxially fixed on the two synchronous transmission shafts respectively; a rotating connecting block is provided in the middle section of each synchronous transmission shaft, and a sampling petal shell is fixedly connected to the end of the rotating connecting block; the two sampling petal shells rotate synchronously with the synchronous transmission shafts to open and close, and together splice into a cylindrical cavity when closed.

[0011] Optionally, the pneumatic sampling assembly further includes a pneumatic control mechanism; the pneumatic control mechanism includes a driven gear, a sealing piston, a support rod, a transmission adapter block, and a drive rack; the driven gear is coaxially fixed to the end of one of the synchronous transmission shafts; the sealing piston is slidably disposed in the drive cylinder cavity; the drive rack is slidably disposed in the rack guide cavity and meshes with the driven gear; the sealing piston is connected to the drive rack through the support rod and the transmission adapter block; the sampling seat is provided with a branch air pipe, which is respectively connected to the drive cylinder cavity, the flexible buoyancy bag, and the air delivery hose.

[0012] Optionally, a pressure relief hole is provided at one end of the drive cylinder chamber that extends away from the sealed piston, and the pressure relief hole penetrates the side wall of the sampling seat to connect with the external environment.

[0013] Optionally, the sampling housing is provided with a first locking mechanism: the first locking mechanism includes a first elastic locking tongue and a first unlocking button; the first elastic locking tongue is disposed on one side of the rack guide cavity, and a pressure spring is provided at the bottom of the first elastic locking tongue to push it upward; the first unlocking button is fixed to the top of the first elastic locking tongue, and the first unlocking button extends upward through the sampling housing and is located directly below the linkage pressure plate; the drive rack is provided with a first locking hole; when the sampling valve shell is in the open state, the first elastic locking tongue is engaged in the first locking hole to lock the drive rack at the first stroke end; when the flexible buoyancy bladder contracts, causing the linkage pressure plate to move downward and pressing the first unlocking button, the first elastic locking tongue is pressed out of the first locking hole to release the lock on the drive rack.

[0014] Optionally, the sampling housing is provided with a second locking mechanism: the second locking mechanism includes a second elastic locking tongue and a second unlocking button; the second elastic locking tongue is disposed on the other side of the rack guide cavity, and the top of the second elastic locking tongue is provided with an elastic element that presses it downward; the second unlocking button is fixed to the lower end of the second elastic locking tongue and extends downward through the sampling housing; the driving rack is provided with a second locking hole; when the sampling valve shell is driven by the sealing piston and is in a closed state, the second elastic locking tongue is engaged in the second locking hole under the action of elasticity, so as to lock the driving rack at the second stroke end point, thereby maintaining the closed state of the sampling valve shell.

[0015] The beneficial effects of this invention are as follows: The device, through the combination of a support base, a horizontal guide rail, and a flexible hinged chain, constructs a power platform that combines rigid guidance with flexible conveying characteristics, ensuring that the pneumatic sampling component can smoothly translate along a preset trajectory. The drive mechanism employs a drive roller with radial positioning grooves. Through the physical meshing between the grooves and the chain pins, a forced transmission similar to a gear pair is achieved, effectively preventing slippage of the flexible body during conveying and ensuring precise control of sampling depth and position. This solution also inserts the gas delivery hose inside the flexible articulated chain, using the chain structure formed by the pin and side plate as a physical barrier to provide axial constraint and mechanical protection for the hose throughout its entire stroke. This solves the problems of entanglement, kinking, and outer wall wear that easily occur in flexible pipelines in complex bending environments such as inverted siphons. When entering a curved pipeline, this articulated chain structure can follow the pipeline's bend and move forward by relying on its single-degree-of-freedom articulation characteristics. At the same time, its lateral rigidity effectively resists the spin caused by water flow disturbance, ensuring that the end pneumatic sampling component always arrives at the work area accurately with a stable posture, significantly improving the operational reliability and system integration of sampling in complex pipeline networks.

[0016] Other advantages, objectives, and features of the invention will be set forth in the following description and will be apparent to those skilled in the art in some respects, or may be learned by practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0017] To make the objectives, technical solutions, and beneficial effects of this invention clearer, the following figures are provided for illustration: Figure 1 A schematic diagram of the overall sampling device of this invention embodiment; Figure 2 A schematic diagram of the first integral structure of the support base according to an embodiment of the invention; Figure 3 A schematic diagram of the second integral structure of the support base according to an embodiment of the present invention; Figure 4 A schematic diagram of the overall structure of the flexible hinged chain body according to an embodiment of the present invention; Figure 5 A schematic diagram of the overall structure of the pneumatic sampling assembly according to an embodiment of the invention; Figure 6 A schematic diagram of the internal structure of the pneumatic sampling assembly according to an embodiment of the invention; Figure 7 A cross-sectional view of the sampling valve shell of the pneumatic sampling assembly according to an embodiment of the invention; Figure 8 A schematic diagram of the inflated flexible buoyancy bag of this invention is shown in the embodiment. Figure 9 A schematic diagram of the gas sampling valve shell in the closed state of this embodiment of the invention; Figure 10 Schematic diagram of branch tracheal distribution according to an embodiment of the invention: The following are labeled in the attached diagram: 1. Support base; 11. Support rear plate; 12. Horizontal guide rail; 13. Vertical support rod; 14. Vertical bracket; 15. Power drive shaft; 16. Motor; 17. Drive roller; 171. Radial positioning groove; 172. Clearance ring groove; 2. Flexible hinge chain; 21. Connecting side plate; 22. First hinge pin; 23. Second hinge pin; 24. End long pin; 25. Center through hole; 3. Moving carriage; 31. Pneumatic power source; 32. Gas delivery hose; 33. Limiting block; 4. Pneumatic sampling assembly; 41. Sampling seat; 411. Through channel; 412. 42. Rack guide cavity; 43. Lower positioning ring; 44. Support connecting plate; 45. Guide column; 46. Upper guide ring; 47. Linkage pressure plate; 58. Flexible buoyancy bladder; 59. Synchronous transmission shaft; 50. Rotating connecting block; 51. Sampling valve shell; 52. Driven gear; 53. Driven cylinder cavity; 54. Pressure relief hole; 55. Branch air pipe; 56. Sealing piston; 57. Transmission adapter block; 58. Drive rack; 58. First locking hole; 58. Second locking hole; 59. Support rod; 60. First elastic locking tongue; 61. First unlocking button; 62. Second elastic locking tongue; 63. Second unlocking button. Detailed Implementation

[0018] 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.

[0019] Please refer to the figures. 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 are not intended to limit the scope of the invention. Therefore, they 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 disclosed technical content. Furthermore, the terms such as "upper," "lower," "left," "right," "middle," and "one" used in this specification are merely for clarity and are 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.

[0020] 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.

[0021] This invention provides a flexible hinged chain sampling device for urban inverted siphons, such as... Figure 1 , Figure 2 and Figure 3As shown, this device has a support base 1 that serves as the foundation for the overall structure. The support base 1 is a horizontally arranged rectangular plate structure with sufficient load-bearing area to support all the upper mechanical components. At the rear edge of the support base 1, a vertically arranged rear support plate 11 is provided, with its bottom edge rigidly connected to and perpendicular to the rear end face of the support base 1. On the front-facing side of the rear support plate 11, two parallel horizontal guide rails 12 extend vertically forward in the horizontal direction. These two horizontal guide rails 12 are equally spaced in the horizontal plane, and their length extends continuously from the rear end of the support base 1 to above the front end. To improve the structural stability and bending strength of the horizontal guide rails 12 in the cantilevered state, multiple vertical support rods 13 are provided on the underside of each horizontal guide rail 12. These vertical support rods 13 are arranged in a longitudinal linear array between the horizontal guide rail 12 and the support base 1. The top of each vertical support rod 13 is fixedly connected to the bottom surface of the horizontal guide rail 12, and its bottom end is vertically supported downward and firmly welded to the upper surface of the support base 1.

[0022] At the front end of the support base 1, corresponding to the two sides of the ends of the horizontal guide rails 12, two symmetrical vertical supports 14 are vertically arranged. These two vertical supports 14 are located on the outer sides of the two horizontal guide rails 12, and their bottoms are fixed to the front sides of the support base 1, forming a gantry-type support structure. Between the two vertical supports 14, a power drive shaft 15 is horizontally rotatable via a bearing seat. The axis of the power drive shaft 15 is perpendicular to the extension direction of the horizontal guide rails 12 and is located in the upper-middle position of the two vertical supports 14. A motor 16 is fixedly installed on the outer wall of one of the vertical supports 14. The output shaft of the motor 16 passes through the vertical support 14 via a coupling and is coaxially connected to one end of the power drive shaft 15. At the middle position of the power drive shaft 15, a cylindrical drive roller 17 is coaxially fixed, and the axial length of the drive roller 17 is less than the length of the power drive shaft 15. On the outer circumferential surface of the drive roller 17, multiple radial positioning grooves 171 are formed in a radially recessed and uniformly arrayed circumferential direction. The cross-section of these radial positioning grooves 171 is a semi-circular or rectangular groove that matches the outer diameter of the pin.

[0023] like Figure 1 , Figure 2 and Figure 3 and Figure 4As shown, a flexible hinged chain 2 is slidably mounted on two horizontal guide rails 12. This flexible hinged chain 2 is a long chain assembly composed of various interconnected structural units. The flexible hinged chain 2 includes multiple connecting side plates 21, multiple first hinge pins 22, and multiple second hinge pins 23. The first hinge pins 22 and second hinge pins 23 are arranged alternately and at equal intervals along the length of the chain. Each connecting side plate 21 has a regular elongated plate structure, and two identical connecting side plates 21 are symmetrically arranged between each pair of adjacent first hinge pins 22 and second hinge pins 23. These two connecting side plates 21 are located at the axial ends of the first hinge pins 22 and second hinge pins 23, respectively, and the two ends of the connecting side plates 21 are rotatably hinged to the ends of the first hinge pins 22 and second hinge pins 23 through hinge holes. In terms of geometric dimensions, the axial length of the first hinge pin 22 is designed to be relatively long, and its length dimension is significantly greater than the distance between the two parallel horizontal guide rails 12; while the axial length of the second hinge pin 23 is designed to be relatively short, and its length dimension is less than the distance between the two horizontal guide rails 12.

[0024] Based on the aforementioned specific length design, the flexible articulated chain 2 slides on two parallel horizontal guide rails 12 in a foldable, undulating state. Specifically, the axial ends of the first articulated pin 22 are respectively mounted and supported on the upper surfaces of the two horizontal guide rails 12, while the adjacent second articulated pin 23, being shorter, has its ends naturally hanging down into the open space below the two horizontal guide rails 12. The connecting side plates 21 are entirely located in the gap between the two horizontal guide rails 12, and the outer walls of the two outermost connecting side plates 21 maintain sliding contact with the inner walls of the two horizontal guide rails 12, thereby providing lateral limiting guidance for the movement of the chain. When the flexible articulated chain 2 is subjected to force and moves forward along the horizontal guide rails 12 and slides out from its front end, the first articulated pin 22 and the second articulated pin 23 will sequentially and precisely fall into the radial positioning grooves 171 opened on the surface of the drive roller 17. At this time, the drive roller 17 supports and limits the pin shaft through the groove structure on its surface, and drives the flexible hinge chain 2 to extend vertically downward for output.

[0025] At the very end of the flexible articulated chain 2, a long end pin 24 for end-positioning is provided. The axial length of this long end pin 24 is not only longer than the second articulated pin 23, but also longer than all the first articulated pins 22 in the chain. To facilitate stroke control with this long end pin 24, a "7"-shaped stop block 33 is fixedly installed at the upper end of each of the two vertical supports 14. These two stop blocks 33 do not extend beyond the front end of the horizontal guide rail 12 in spatial position, and the lateral spacing between them has specific requirements: the spacing is set to be greater than the length of all the first articulated pins 22, but less than the length of the last long end pin 24. Through this dimensional interference, when the flexible articulated chain 2 slides to its limit position, the stop block 33 can accurately prevent the long end pin 24 from continuing to move forward, thereby preventing the flexible articulated chain 2 from completely sliding off the horizontal guide rail 12.

[0026] In such Figures 1-4 As shown, a movable carriage 3 for supporting the power distribution component is also installed across the two parallel horizontal guide rails 12. The movable carriage 3 has a flat rectangular frame structure, with its left and right ends slidably connected to the two horizontal guide rails 12 via sliding sleeves with a low coefficient of friction, allowing the movable carriage 3 to move freely back and forth along the axis of the horizontal guide rails 12. At the upper center of the movable carriage 3, a pneumatic power source 31, serving as the core of the machine's power output, is fixedly installed with bolts. This pneumatic power source 31 has a pneumatic interface for outputting compressed air, and a highly flexible and pressure-resistant air delivery hose 32 is sealed and connected to this interface.

[0027] The gas delivery hose 32 originates from the pneumatic power source 31 and extends towards the flexible hinged chain 2, employing an axially shuttled arrangement. To achieve concealed guidance and physical protection of the pipeline, a central through-hole 25 is perpendicularly formed along the axial direction at the geometric center of each first hinge pin 22 and each second hinge pin 23 of the flexible hinged chain 2. These central through-holes 25 are arranged coaxially in a straight line when the chain is laid flat, thus providing a protected internal channel for the gas delivery hose 32. The gas delivery hose 32 passes sequentially through these central through-holes 25 of the first and second hinge pins 22 and is constrained on the central axis of the flexible hinged chain 2. This allows the gas delivery hose 32 to change shape synchronously with the folding, unfolding, or drooping of the chain, effectively preventing the pipeline from tangling, breaking, or mechanically abrading with external structures in the narrow inverted siphon environment.

[0028] In the intersection area of ​​the flexible hinge chain 2 and the power transmission component, the device solves the motion interference problem through a specific avoidance structure. On the drive roller 17, which is coaxially fixed to the aforementioned power drive shaft 15, a avoidance groove 172 is recessed inward in the middle area of ​​its circumferential surface, surrounding the drive roller 17. This avoidance groove 172 is located at the geometric center of the drive roller 17 in the axial direction, and its radial depth is designed to be greater than the depth of the radial positioning groove 171 on the surface of the drive roller 17, and its groove width is adapted to the outer diameter of the air supply hose 32. When the power drive shaft 15 drives the drive roller 17 to rotate, causing the radial positioning groove 171 to precisely engage and move the first hinge pin 22 and the second hinge pin 23, the air supply hose 32, which passes through the central through hole 25 of these pins, will be precisely embedded in the internal space of the avoidance groove 172. Due to the presence of the clearance groove 172, the air supply hose 32 is always in a non-pressurized, suspended, and yielding state as it rotates around the drive roller 17 with the pin and extends downwards. This ensures that the drive roller 17 does not exert radial pressure on the air supply hose 32 located at the center of the pin while applying a strong driving force to the pin.

[0029] like Figures 5-10 As shown, a pneumatic sampling assembly 4 is fixedly connected to the front end of the flexible hinged chain 2. Between the two connecting side plates 21 at the very front of the flexible hinged chain 2, a sampling seat 41 serving as a core support is provided. The two sides of the sampling seat 41 are in close contact with and fixedly connected to the inner walls of the two connecting side plates 21, allowing it to change position synchronously with the movement of the chain. The sampling seat 41 has a block-shaped geometric structure, with a through-channel 411 extending vertically from the bottom to the top at its geometric center. Furthermore, within the internal solid portion of the sampling seat 41, a cylindrical drive cylinder chamber 54 and a rack guide chamber 412 for accommodating the movement of transmission components are respectively formed side-by-side. To maintain communication between the internal cavity and the external environment, a pressure relief hole 541 communicating with the external environment is also provided on the side wall of the sampling seat 41. One end of the pressure relief hole 541 connects to the interior of the drive cylinder chamber 54, while the other end opens onto the outer surface of the sampling seat 41.

[0030] At the upper end of the sampling seat 41, a buoyancy-driven support structure is provided. This structure includes a horizontally arranged annular positioning lower ring 42, which is rigidly fixed to the upper end of the sampling seat 41 by multiple radially arranged support plates 43. One end of these support plates 43 is anchored to the top edge of the sampling seat 41, and the other end extends horizontally outward to support the positioning lower ring 42, so that the positioning lower ring 42 is stably and coaxially surrounding the outer perimeter of the top of the sampling seat 41. On the top surface of the sampling seat 41, several parallel guide columns 44 are also vertically arranged upwards. These guide columns 44 are arranged in a circular array around the axis of the central through channel 411, providing vertical mechanical limitation and guidance for the upper moving components.

[0031] Above the lower positioning ring 42, a vertically movable upper guide ring 45 is positioned. To ensure stable lifting and lowering of the upper guide ring 45, a linkage pressure plate 46 is fixedly connected to its inner diameter. The linkage pressure plate 46 is entirely located within the inner cavity of the upper guide ring 45, and it has sliding engagement holes corresponding to the number and position of the guide pillars 44, allowing the linkage pressure plate 46 to slide vertically onto these guide pillars 44. Through this connection method, the upper guide ring 45 and the linkage pressure plate 46 form a set of slidable piston-type guide pairs in the vertical direction.

[0032] Between these annular support structures, a flexible buoyancy bladder 47 for containing gas is disposed. This flexible buoyancy bladder 47 is made of a stretchable, airtight material and is positioned between the upper guide ring 45 and the lower positioning ring 42. The upper opening edge of the flexible buoyancy bladder 47 is circumferentially sealed to the bottom surface of the upper guide ring 45, while its lower opening edge is similarly sealed to the top surface of the lower positioning ring 42. Thus, the flexible buoyancy bladder 47, the upper guide ring 45, and the lower positioning ring 42 together form a variable-volume closed bladder structure on the top outer periphery of the sampling base 41, and the vertical length of the flexible buoyancy bladder 47 directly determines the axial distance between the upper guide ring 45 and the lower positioning ring 42.

[0033] Inside the through-channel 411 of the sampling base 41, two parallel synchronous drive shafts 51 are symmetrically and horizontally rotatably mounted. These two synchronous drive shafts 51 span the inner cavity of the through-channel 411, and their ends are rotatably supported on the opposite inner sidewalls of the sampling base 41 via bushings or bearings. To achieve dynamic coupling and phase synchronization between the two shafts, a coaxial transmission gear is fixed to each of the two synchronous drive shafts 51, directly meshing with each other. Through the meshing of these two gears, the rotation of one shaft can drive the other shaft to rotate synchronously at the same speed but in opposite directions.

[0034] At the midpoint of each synchronous drive shaft 51, a rotating connecting block 511 is fixedly installed, extending radially outward. This rotating connecting block 511 acts as a cantilevered support structure, its root enveloping the outer circumference of the synchronous drive shaft 51, while its end extends away from the axis. At the outer ends of the rotating connecting blocks 511 corresponding to the two synchronous drive shafts 51, a sampling valve shell 52 is fixedly installed. The sampling valve shell 52 is geometrically a regular semi-cylindrical shape, its structure composed of a high-strength thin-walled metal structure. The sampling valve shell 52 has a closed semi-circular arc-shaped sidewall and an opposing planar side. This planar side has a hollow structure, and the shell wall of the hollow area is relatively thin, thus forming an opening with a sharp edge.

[0035] In terms of physical connection, the end of the rotating connecting block 511 is rigidly connected to the side of the semi-cylindrical sampling valve shell 52. The specific connection point is located at the ridge line where the planar side edge and the arc surface edge of the sampling valve shell 52 intersect. This offset connection layout ensures that when the synchronous drive shaft 51 rotates, the two sampling valve shells 52 can perform symmetrical fan-shaped opening and closing movements around their respective axes. When the two sampling valve shells 52 approach each other and finally close under the drive of the synchronous drive shaft 51, the planar side edges of the two semi-cylinders abut against each other, thus spatially splicing together and constructing a closed cylindrical cavity. At this time, most of the structure of the cylindrical cavity is vertically exposed downward from the bottom opening of the sampling seat 41.

[0036] Furthermore, at the final node of the power transmission, one end of one of the synchronous drive shafts 51 passes through the inner wall of the through channel 411 and extends further into the solid interior of the sampling seat 41. At the shaft end extending into the sampling seat 41, a driven gear 53 is coaxially fixedly mounted. The driven gear 53 is completely accommodated in the transmission chamber reserved inside the sampling seat 41 and is used to receive mechanical power from the upper drive mechanism.

[0037] The internal structure of the sampling base 41 includes a drive cylinder chamber 54, which has a cylindrical concave structure. Two branch air pipes 55, serving as airflow channels, are connected to the side wall of one end of the drive cylinder chamber 54. One branch air pipe 55 extends upwards and achieves airtight communication with the bottom air inlet of the upper flexible buoyancy bladder 47; the other branch air pipe 55 extends laterally and exits through the side shell of the sampling base 41, with its end interface sealingly connected to the air delivery hose 32 extending from the direction of the flexible hinge chain 2, thereby introducing the pressure from the external pneumatic power source 31 into the internal system.

[0038] Inside the cylindrical interior space of the drive cylinder cavity 54, a sealing piston 56 is precisely matched to its inner diameter. The outer circumferential surface of the sealing piston 56 is tightly fitted with the inner wall of the cylinder, forming a dynamically sealing interface that can slide axially. The length direction of the sealing piston 56 is arranged along the cylinder axis and is always located inside the drive cylinder cavity 54 to receive air pressure. The sealing piston 56 is connected to a support rod 59, which serves as the power output end and slides out of the drive cylinder cavity 54 to the outside of the cavity. At this end position where the sealing piston 56 extends, a transmission adapter block 57 is connected. The lower end of the transmission adapter block 57 is fixedly connected to the support rod 59.

[0039] At the upper end of the transmission adapter block 57, a drive rack 58 serving as a linear transmission element is further connected. This drive rack 58 is elongated, with a continuously arranged tooth structure machined on one side surface, and the entire rack is housed within a pre-reserved rack guide cavity 412 inside the sampling seat 41. The inner wall space of the rack guide cavity 412 provides a running track for the drive rack 58, limiting its radial offset during movement. In this structural layout, the tooth surfaces of the drive rack 58 are in an interlocking meshing state with the driven gear 53 at the end of the aforementioned synchronous transmission shaft 51 that penetrates the sampling seat 41, thereby converting the linear displacement of the rack into the rotational motion of the gear. A pressure relief hole 541 penetrating the side wall of the sampling seat 41 is also provided on the other end face of the drive cylinder chamber 54 away from the piston extension end. This pressure relief hole 541 establishes a free air passage between the back pressure chamber of the drive cylinder chamber 54 and the external environment of the sampling seat 41.

[0040] In the rack guide cavity 412 inside the sampling base 41, a set of elastic locking mechanism with bidirectional locking function is provided to achieve precise limiting and mechanical locking of the endpoint of the driving rack 58's running trajectory. On one end wall of the rack guide cavity 412, there is a storage slot for guiding the reciprocating extension and retraction of the locking tongue, and a first elastic locking tongue 61 is provided inside the storage slot. A pressure spring is installed between the bottom of the first elastic locking tongue 61 and the bottom surface of the storage slot, so that the first elastic locking tongue 61 always has an elastic tendency to move upward and protrude out of the slot in the free state. On the top plane of the first elastic locking tongue 61, a first unlocking button 62 with a cylindrical structure is vertically fixed. In order to enable the first unlocking button 62 to be triggered by external action, a vertically penetrating guide channel is opened in the top solid of the sampling base 41, and the top of the first unlocking button 62 protrudes upward from the top surface of the sampling base 41 through the guide channel. In terms of spatial position, the first unlock button 62 of the exposed part is located directly below the aforementioned linkage pressure plate 46, and the axes of the two are aligned in the vertical direction, so that the linkage pressure plate 46 can physically contact and press down the first unlock button 62 during the downward movement.

[0041] Corresponding to the above structure, a receiving cavity for reverse locking is also provided on the other side wall of the rack guide cavity 412, and a second elastic locking tongue 63 is provided in this cavity. Opposite to the force direction of the first elastic locking tongue 61, an elastic element is disposed between the top of the second elastic locking tongue 63 and the top surface of the receiving cavity, giving it a tendency to move downwards and return to its original position when stationary. A second unlocking button 64 is firmly fixedly provided on the lower end face of the second elastic locking tongue 63. A through hole is provided at a corresponding position on the bottom shell of the sampling base 41 for the button to pass through. The end of the second unlocking button 64 protrudes vertically downwards through this through hole and is exposed to the external environment of the bottom surface of the sampling base 41, thus providing an operating point for manual pressing.

[0042] like Figure 8 , Figure 9As shown, the driven rack 58 has positioning structures at both ends of its main body for physical engagement. At the right end of the rack 58, a first locking hole 581 perpendicular to its surface is provided. The geometry of this first locking hole 581 matches the outer contour of the top of the first elastic latch 61, so that when the rack 58 moves to its limit stroke, the first elastic latch 61 can automatically engage in the first locking hole 581 under elastic force. Similarly, a second locking hole 582 corresponding to its structure is provided at the left end of the rack 58. The axis of this second locking hole 582 overlaps with the vertical movement trajectory of the second elastic latch 63. When the rack 58 slides to the left along the rack guide cavity 412 and contacts the side wall, the second elastic latch 63 is forced into and engaged inside the second locking hole 582 under the pressure of the top spring. With this arrangement, the drive rack 58, the first elastic locking tongue 61 and the second elastic locking tongue 63 form two sets of mechanical limiting and locking pairs located at the two ends of the stroke in the rack guide cavity 412 of the sampling seat 41, and the first unlocking button 62 and the second unlocking button 64 respectively achieve outward mechanical extension through the upper and lower walls of the sampling seat 41.

[0043] At the initial stage of sampling the bottom of the inverted siphon, the motor 16, fixed on the vertical support 14, is first activated by the control system. The torque generated by the motor 16 is precisely transmitted to the power drive shaft 15 through the coupling, which in turn drives the coaxially fixed drive roller 17 to begin rotating smoothly. At this time, the flexible articulated chain 2, which was originally placed on the horizontal guide rail 12 in a folded and undulating state, begins to enter the dynamic conveying process. The drive roller 17 has multiple radial positioning grooves 171 arrayed on its circumferential surface. As the roller rotates, these positioning grooves engage with the first hinge pin 22 and the second hinge pin 23 at the front end of the flexible articulated chain 2 in sequence. During the conveying process, since the length of the first hinge pin 22 is greater than the distance between the two horizontal guide rails 12, its two ends are firmly attached to the upper surface of the guide rails and slide; while the second hinge pin 23, due to its shorter length, naturally hangs down at both ends under the action of gravity in the space below between the two guide rails, so that the entire chain presents a wave-shaped folded structure that makes efficient use of space. As the drive roller 17 continues to move, the flexible articulated chain 2 slides along the horizontal guide rail 12 from the rear end to the front end, and finally slides out from the front end of the guide rail. After sliding out, the pin is firmly supported by the radial positioning groove 171 of the drive roller 17, and its horizontal displacement changes to a vertical downward linear extension. During this descent, when the pin is engaged in the radial positioning groove 171 and rotates around the roller, the air supply hose 32 located in the middle of the pin is precisely embedded in the avoidance ring groove 172 on the cross-section of the drive roller 17. This deep groove avoidance design ensures that the drive roller 17, while applying a huge vertical output driving force to the chain, will not cause radial compression or friction to the air supply hose 32, thereby ensuring the smooth airflow and physical safety of the pneumatic system in complex descent environments. Finally, the flexible articulated chain 2, carrying the sampling equipment at the end, descends vertically along the vertical pipe to the predetermined underwater operating depth.

[0044] After the pneumatic sampling assembly 4 is lowered to the bottom of the inverted siphon vertical pipe along with the flexible hinged chain 2, the pneumatic power source 31 delivers compressed air to the front end through the air delivery hose 32. The airflow is injected into the flexible buoyancy bladder 47 through the branch air pipe 55 inside the sampling seat 41. As the gas is filled, the flexible buoyancy bladder 47 expands rapidly, causing the guide ring 45 and the linkage pressure plate 46 to rise along the guide column 44, giving the entire pneumatic sampling assembly 4 sufficient buoyancy to counteract its own weight. Under the combined effect of buoyancy and the force of the water flow, the pneumatic sampling assembly 4 smoothly enters the bottom horizontal pipe and remains floating above the inner cavity of the horizontal pipe. This "floating top" movement effectively avoids collisions or jamming with the sediment or obstacles at the bottom of the horizontal pipe during the lateral movement of the equipment, ensuring that the equipment can smoothly reach the preset sampling operation area. When the equipment determines that it has reached the sampling point based on the delivery length of the flexible hinged chain 2, the pneumatic power source 31 switches to the air extraction mode and begins to recover the gas in the air delivery hose 32. As the gas inside the flexible buoyancy bladder 47 is expelled, the bladder volume shrinks rapidly, and the pneumatic sampling assembly 4, losing buoyancy support, steadily sinks to the sediment surface at the bottom of the horizontal tube. Simultaneously with sinking, due to the shortening of the vertical height of the flexible buoyancy bladder 47, the guide ring 45, originally positioned higher, moves synchronously downwards along the guide column 44 via the linkage pressure plate 46. At the end of this stroke, the linkage pressure plate 46 precisely contacts and presses vertically downwards the first unlocking button 62 exposed at the top of the sampling seat 41. This action causes the first elastic locking tongue 61 to overcome the pressure of the bottom spring and retract downwards, disengaging it from the first locking hole 581 on the drive rack 58. Through this buoyancy and mechanical linkage logic, the device automatically releases the lock on the actuator the instant it sinks to the bottom, preparing for the subsequent power connection of the sampling valve shell 52.

[0045] After the flexible buoyancy bladder 47 retracts and triggers the unlocking of the linkage pressure plate 46, the device enters the sampling closure stage driven by negative pressure. At this time, the pneumatic power source 31 continuously performs the suction action, creating a negative pressure environment inside the air supply hose 32 and the drive cylinder chamber 54 connected to it. Under this continuous suction action, the originally extended sealing piston 56 is driven by the pressure difference to "retract" towards the bottom of the cylinder. The rigidly connected support rod 59 and transmission adapter block 57 synchronously drive the drive rack 58 to perform a reverse linear displacement in the rack guide cavity 412. Since the drive rack 58 is meshed with the driven gear 53, the rack's retraction motion precisely drives the synchronous transmission shaft 51 to rotate in the opposite direction, which in turn causes the two open semi-cylindrical sampling valve shells 52 to move towards the center and finally close through the rotating connecting block 511. As the sampling valve shells 52 close, their sharp edges on the hollow side cut into the sediment, sealing the sample inside the cylindrical cavity formed by the splicing of the two valve shells. When the drive rack 58 moves to the other end of its stroke due to continuous air extraction, the second elastic locking tongue 63 on the side wall of the rack guide cavity 412 automatically pops out downward under the drive of the top elastic element and firmly locks into the second locking hole 582 at the end of the drive rack 58. This linkage design of "air extraction closure" and "end locking" ensures that the sampling mechanism can remain tightly closed even if the air pressure is completely lost or encounters external impact, preventing sample leakage. At the same time, since the air passage is still in a vacuum or low-pressure state after air extraction, the flexible buoyancy bladder 47 remains collapsed, and the pressure relief hole 541 balances the cylinder back pressure, ensuring smooth piston recovery action and reliable final locking, laying the foundation for subsequent lifting and recovery operations via the flexible hinged chain 2.

[0046] After the sampling operation is completed and the sampling valve shell 52 is stably locked by the second elastic locking tongue 63, the device enters the overall recovery stage. First, the control system commands the motor 16 to rotate in the opposite direction, and the power is transmitted to the drive roller 17 via the power drive shaft 15, causing it to start rotating in the reverse direction. At this time, the radial positioning groove 171 on the surface of the drive roller 17 captures and engages the flexible articulated chain 2, which is in a vertically drooping state, and the chain is steadily lifted upward through the mechanical cooperation between the pin and the groove. During this lifting process, the air supply hose 32, which passes through the pin, retracts synchronously with the chain and is continuously protected by the avoidance ring groove 172 in the middle of the drive roller 17, avoiding pressure damage to the pipeline caused by the lifting tension. When the flexible articulated chain 2 is lifted to the intersection of the horizontal guide rail 12 at the front end of the support base 1, ... Because the axial length of the first hinge pin 22 is longer than the distance between the two horizontal guide rails 12, when it rotates with the roller above the guide rails, both ends of the pin will again precisely cross over and mount the upper surfaces of the two horizontal guide rails 12 for support. Meanwhile, because the axial length of the second hinge pin 23 is shorter than the distance between the guide rails, it cannot obtain support from the guide rails and, under the traction of gravity and the connecting side plate 21, naturally falls from the gap between the two guide rails into the space below the horizontal guide rails 12. As the motor 16 continues to drive, the entire flexible hinged chain 2 is continuously pushed towards the supporting rear plate 11. In this alternating support and descent state, the chain restores its orderly folded and undulating shape on the horizontal guide rails 12, achieving high-density spatial reset storage.

[0047] Finally, it should be noted that the above preferred embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail through the above preferred embodiments, those skilled in the art should understand that various changes can be made to it in form and detail without departing from the scope defined by the claims of the present invention.

Claims

1. A flexible hinged chain sampling device for urban inverted siphons, characterized in that: It includes a support base (1), a drive mechanism, a flexible hinge chain (2), a movable carriage (3), and a pneumatic sampling assembly (4); The rear end of the support base (1) is vertically provided with a support back plate (11), and two parallel horizontal guide rails (12) extend forward along the horizontal direction on the support back plate (11). The drive mechanism is located at the front end of the support base (1) and includes two symmetrically arranged vertical brackets (14), a power drive shaft (15) rotatably arranged between the vertical brackets (14), a motor (16) for driving the power drive shaft (15) to rotate, and a drive roller (17) coaxially fixed in the middle of the power drive shaft (15); the outer surface of the drive roller (17) is evenly provided with multiple radial positioning grooves (171). The flexible hinge chain (2) is slidably disposed on the horizontal guide rail (12), including alternating first hinge pins (22) and second hinge pins (23), and a connecting side plate (21) hinged between adjacent first hinge pins (22) and second hinge pins (23). The movable slide (3) is slidably mounted on the horizontal guide rail (12). A pneumatic power source (31) is installed on the movable slide (3). The pneumatic power source (31) is connected to a gas delivery hose (32) that passes through the flexible hinge chain (2). The pneumatic sampling component (4) is fixedly connected to the front end of the flexible hinge chain (2), and the pneumatic sampling component (4) is connected to the gas delivery hose (32).

2. The flexible articulated chain sampling device for urban inverted siphons according to claim 1, characterized in that: The axial length of the first hinge pin (22) is greater than the distance between the two horizontal guide rails (12), and the two ends of the first hinge pin (22) are mounted on the upper surface of the horizontal guide rail (12); the axial length of the second hinge pin (23) is less than the distance between the two horizontal guide rails (12), and the two ends of the second hinge pin (23) hang below the horizontal guide rail (12); the flexible hinge chain (2) is supported by the alternating support of the first hinge pin (22) and the second hinge pin (23), and presents a folded and undulating state on the horizontal guide rail (12).

3. The flexible articulated chain sampling device for urban inverted siphons according to claim 2, characterized in that: The first hinge pin (22) and the second hinge pin (23) are both provided with a central through hole (25) along the axial direction at their geometric center positions. The air supply hose (32) passes through the central through hole (25) in sequence. The drive roller (17) has an inwardly recessed avoidance ring groove (172) in the middle of its circumferential surface. The depth of the avoidance ring groove (172) is greater than the depth of the radial positioning groove (171). When the flexible hinge chain (2) rotates around the drive roller (17), the air supply hose (32) is embedded in the avoidance ring groove (172).

4. The flexible articulated chain sampling device for urban inverted siphons according to claim 1, characterized in that: The horizontal guide rail (12) has multiple vertical support rods (13) arranged in a longitudinal linear array on its lower side. The two ends of the vertical support rods (13) are fixedly connected to the horizontal guide rail (12) and the support base (1), respectively. The flexible hinge chain (2) has an end long pin (24) at its far end. Each of the vertical brackets (14) has a limiting block (33) fixed at its upper end. The lateral distance between the two limiting blocks (33) is greater than the length of the first hinge pin (22) and less than the length of the end long pin (24).

5. The flexible articulated chain sampling device for urban inverted siphons according to claim 1, characterized in that: The pneumatic sampling assembly (4) includes a sampling base (41) and a buoyancy drive support structure; the sampling base (41) includes a through channel (411) that runs through the top and bottom surfaces; the interior of the sampling base (41) also has a drive cylinder chamber (54) and a rack guide chamber (412) arranged in parallel; the buoyancy drive support structure includes a lower positioning ring (42), a support connecting plate (43), a guide column (44), an upper guide ring (45), a linkage pressure plate (46), and a flexible buoyancy bladder (47). 7) The lower positioning ring (42) is fixed to the upper periphery of the sampling seat (41) by the supporting connecting plate (43); the guide column (44) is vertically fixed to the top surface of the sampling seat (41); the linkage pressure plate (46) is slidably sleeved on the guide column (44), and the upper guide ring (45) is fixedly connected to the outer periphery of the linkage pressure plate (46); the flexible buoyancy bag (47) is connected between the lower positioning ring (42) and the upper guide ring (45).

6. The flexible articulated chain sampling device for urban inverted siphons according to claim 5, characterized in that: The pneumatic sampling assembly (4) also includes a synchronous transmission mechanism; the synchronous transmission mechanism includes two parallel synchronous transmission shafts (51), which are rotatably mounted across the through channel (411); the two synchronous transmission shafts (51) are respectively coaxially fixed with meshing transmission gears; each synchronous transmission shaft (51) is provided with a rotating connecting block (511) in the middle section, and the end of the rotating connecting block (511) is fixedly connected with a sampling petal shell (52); the two sampling petal shells (52) rotate synchronously with the synchronous transmission shaft (51) to achieve opening and closing, and when closed, they are spliced ​​together to form a cylindrical cavity.

7. The flexible articulated chain sampling device for urban inverted siphons according to claim 6, characterized in that: The pneumatic sampling assembly (4) further includes a pneumatic control mechanism; the pneumatic control mechanism includes a driven gear (53), a sealing piston (56), a support rod (59), a transmission adapter block (57), and a drive rack (58); the driven gear (53) is coaxially fixed to the end of one of the synchronous transmission shafts (51); the sealing piston (56) is slidably disposed in the drive cylinder chamber (54); the drive rack (58) is slidably disposed in the rack guide chamber (412) and meshes with the driven gear (53); the sealing piston (56) is connected to the drive rack (58) through the support rod (59) and the transmission adapter block (57); the sampling seat (41) is provided with a branch air pipe (55), which is connected to the drive cylinder chamber (54), the flexible buoyancy bag (47), and the air supply hose (32) respectively.

8. The flexible articulated chain sampling device for urban inverted siphons according to claim 7, characterized in that: The drive cylinder chamber (54) has a pressure relief hole (541) at one end that extends away from the sealing piston (56). The pressure relief hole (541) penetrates the side wall of the sampling seat (41) to connect with the external environment.

9. The flexible articulated chain sampling device for urban inverted siphons according to claim 7, characterized in that: The sampling seat (41) is provided with a first locking mechanism: the first locking mechanism includes a first elastic locking tongue (61) and a first unlocking button (62); the first elastic locking tongue (61) is disposed on one side of the rack guide cavity (412), and the bottom of the first elastic locking tongue (61) is provided with a pressure spring that pushes it upward; the first unlocking button (62) is fixed to the top of the first elastic locking tongue (61), and the first unlocking button (62) extends upward through the sampling seat (41) and is located directly below the linkage pressure plate (46). The drive rack (58) is provided with a first locking hole (581); when the sampling valve shell (52) is in the open state, the first elastic locking tongue (61) is inserted into the first locking hole (581) to lock the drive rack (58) at the first stroke end; when the flexible buoyancy bladder (47) contracts and drives the linkage pressure plate (46) to move down and press the first unlocking button (62), the first elastic locking tongue (61) is pressed out of the first locking hole (581) to release the lock on the drive rack (58).

10. The flexible articulated chain sampling device for urban inverted siphons according to claim 9, characterized in that: The sampling seat (41) is provided with a second locking mechanism: the second locking mechanism includes a second elastic locking tongue (63) and a second unlocking button (64); the second elastic locking tongue (63) is located on the other side of the rack guide cavity (412), and the top of the second elastic locking tongue (63) is provided with an elastic element that presses it downward; the second unlocking button (64) is fixed to the lower end of the second elastic locking tongue (63) and extends downward through the sampling seat (41); the driving rack (58) is provided with a second locking hole (582); when the sampling valve shell (52) is driven by the sealing piston (56) and is in a closed state, the second elastic locking tongue (63) is inserted into the second locking hole (582) under the action of elastic force, so as to lock the driving rack (58) at the second stroke end point, thereby maintaining the closed state of the sampling valve shell (52).