Thermal desorption sealed sampling device

Abstract

The utility model relates to a pyrogenic desorption technical field especially a kind of pyrogenic desorption sealed sampling device, comprising: workbench;Pyrogenic desorption component is set to the top of the workbench, and with the workbench is connected, for the heat desorption of sample storage tube;Two groups of sampling structure, symmetrically set to the both sides of the pyrogenic desorption component, for sampling;Two groups of exhaust structure, each exhaust structure is set to the outside of the sampling structure, and with the sampling structure is connected, for the gas in the sampling structure is discharged. By inserting sampling structure into exhaust structure, and operating exhaust structure, operating exhaust structure will extract the air inside sampling structure, and discharge, so that sampling structure maintains sub-vacuum state before sampling, realizes the gas in cavity is discharged before sampling, avoids air to influence analysis structure, and it is convenient to use.

Description

Technical Field

[0001] This utility model relates to the field of thermal desorption technology, specifically a thermal desorption sealed sampling device. Background Technology

[0002] Thermal desorption is a technique that uses direct or indirect heating to heat a polluting medium to a specified temperature, causing organic pollutants to volatilize or separate. It can be divided into two categories according to the heating temperature: low-temperature thermal desorption and high-temperature thermal desorption. After thermal desorption is completed, the generated substances need to be analyzed to ensure safe separation. This requires the use of a sampling device to transfer the gaseous substances to a gas chromatograph for detection and analysis.

[0003] However, existing thermal desorption sealed sampling devices work by inserting a needle into a thermal desorption tube to extract the gas and transfer it to a gas chromatograph for analysis. However, the presence of cavities in the needle and sampling tube allows gas to remain inside, which can affect the detection structure. It is also difficult to remove the gas from the cavities before sampling, making the device inconvenient to use. Summary of the Invention

[0004] The purpose of this invention is to solve the problem that existing thermal desorption sealing sampling devices cannot expel the gas in the cavity before sampling, which makes them inconvenient to use.

[0005] To achieve the above objectives, this utility model provides the following technical solution: A thermal desorption sealed sampling device, comprising: Workbench; A thermal desorption assembly is disposed above and connected to the worktable, and is used to perform thermal desorption on the sample storage tube; Two sets of sampling structures are symmetrically arranged on both sides of the thermal desorption component for sampling; Two sets of exhaust structures are provided, each set of exhaust structures is located outside the sampling structure and connected to the sampling structure, and is used to exhaust the gas in the sampling structure.

[0006] Preferably, the exhaust structure includes: Vacuum tube; A vacuum shell, one end of which is connected to the vacuum tube; A conical cover, one end of which is a first opening and the other end is a second opening, the inner diameter of the first opening being smaller than the inner diameter of the second opening; the first opening is connected to the other end of the vacuum shell; A vacuum pump, wherein the output end of the vacuum pump is provided with a flexible hose and is connected to the vacuum tube through the flexible hose; A sealing structure is disposed inside the vacuum shell to seal the first opening; An auxiliary sampling structure is disposed inside the vacuum tube and connected to the sampling structure, and is used to drive the sampling structure to move.

[0007] Preferably, the auxiliary sampling structure includes: A piston plate is disposed inside the vacuum tube, and the edge of the piston plate is in contact with the inner wall of the vacuum tube; The movable component consists of a first round rod and a first ring, wherein the first round rod is fixedly disposed between the piston plate and the first ring; A first screw passes through the piston plate and is fixedly connected to the piston plate; a cavity is formed inside the first screw. The sampling needle has its interior connected to the cavity; the surface of the sampling needle has multiple sets of through holes that are connected to the interior of the sampling needle, allowing air from the vacuum tube to enter the interior of the sampling needle through the through holes.

[0008] Preferably, the sealing structure includes: A worm gear, one side of which is slidably connected to the vacuum housing; a groove is provided on the other side of the worm gear; A worm gear meshes with the worm wheel; the worm gear passes through the vacuum housing and is rotatably connected to the vacuum housing. A handwheel, wherein the shaft of the handwheel is fixedly connected to one end of the worm gear; Multiple sets of sliders, each set of sliders is disposed in the slide groove and is slidably connected to the worm gear through the slide groove; Multiple sets of connectors, one end of each set of connectors being fixedly connected to the end of the slider away from the worm gear; Multiple sets of seals, each set of seals having its edge fixedly connected to the other end of the connector; when the multiple sets of seals come into contact, they can block the first opening.

[0009] Preferably, the sampling structure includes: A sampling tube, one end of which is provided with a threaded sleeve; the threaded sleeve is sleeved on the outside of the first screw and is threadedly connected to the first screw; A sealing plate is disposed inside the sampling tube; A limiting member is disposed in the cavity; the limiting member is composed of a second round rod and a second round ring, and the two ends of the second round rod are respectively fixedly connected to the inner walls of the second round ring and the first screw. An elastic element, the two ends of which are fixedly connected to the sealing plate and the sampling tube respectively, and are sleeved on the outside of the threaded sleeve; The piston assembly consists of a rubber pad and a handle. The edge of the rubber pad is in contact with the inner wall of the sampling tube. The side of the rubber pad away from the sealing plate is fixedly connected to the handle.

[0010] Preferably, the length of the second circular rod is greater than the length of the threaded sleeve, so that when the threaded sleeve is connected to the first screw, the second ring can separate the sealing plate and the threaded sleeve.

[0011] Preferably, it further includes: a movable structure; the movable structure is disposed inside the worktable and is used to move the sampling structure.

[0012] Preferably, the moving structure includes: Two sets of fasteners, each set of fasteners is sleeved on the outside of the vacuum tube and fixedly connected to the vacuum tube; Both sets of movable nuts are located inside the worktable and are slidably connected to the worktable; Two sets of second screws, each set of second screws passing through the movable nut and threadedly connected to the movable nut; A dual-output shaft motor, wherein both ends of the dual-output shaft motor are fixedly connected to one end of the two sets of second screws adjacent to each other.

[0013] Preferably, the thermal desorption assembly includes: The placement component consists of two sets of separable support members, with an arc-shaped notch on the adjacent side of each set of support members; the two sets of support members are joined together to form a heating cavity. An electric heating tube, disposed in the support member, can heat the sample storage tube after being powered on.

[0014] Preferably, the support member has sealing semi-rings at both ends for sealing the heating chamber.

[0015] The beneficial effects proposed by this utility model are as follows: by inserting the sampling structure into the exhaust structure and operating the exhaust structure, the air inside the sampling structure will be extracted and discharged, so that the sampling structure is kept in a sub-vacuum state before sampling, thereby venting the gas in the cavity before sampling, avoiding air from affecting the analysis structure, and facilitating use. Attached Figure Description

[0016] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 for Figure 1 Rear-view 3D schematic diagram of the central connection structure; Figure 3 for Figure 1 A three-dimensional schematic diagram of the middle section connection structure; Figure 4 for Figure 3 Exploded view of the central connecting structure; Figure 5 for Figure 2 A three-dimensional schematic diagram of the internal connection structure of the middle section; Figure 6 for Figure 5 Enlarged 3D schematic diagram of the central connecting structure; Figure 7 for Figure 6 Cross-sectional view of the internal connection structure; Figure 8 for Figure 7 Right view of the central connecting structure; Figure 9 for Figure 7 Enlarged 3D schematic diagram of the central connecting structure; Figure 10 for Figure 8 Enlarged 3D schematic diagram of the central connecting structure; Figure 11 for Figure 10 Exploded view of the central connecting structure; Figure 12 for Figure 11 Left view of the connecting structure.

[0017] In the diagram: 1. Workbench, 2. Placement component, 3. Electric heating element, 4. Vacuum tube, 5. Vacuum shell, 6. Conical hood, 7. Sampling tube, 8. Moving component, 9. Piston plate, 10. First screw, 11. Sampling needle, 12. Limiting component, 13. Sealing plate, 14. Elastic component, 15. Piston component, 16. Worm gear, 17. Worm, 18. Handwheel, 19. Slider, 20. Connecting component, 21. Sealing component, 22. Fixing component, 23. Moving nut, 24. Second screw, 25. Dual output shaft motor, 26. Vacuum pump. Detailed Implementation

[0018] The present invention will be further described below with reference to the accompanying drawings:

[0019] This embodiment:

[0020] Please see Figure 1-12 In this embodiment: a thermal desorption sealed sampling device includes: a workbench 1, a thermal desorption assembly, two sets of sampling structures and two sets of exhaust structures.

[0021] In this embodiment, the thermal desorption assembly is disposed above the workbench 1 and connected to the workbench 1, and is used to perform thermal desorption on the sample storage tube.

[0022] In this embodiment, the sample storage tube can be heated by the thermal desorption component, so that the sample inside the sample storage tube is separated after being heated.

[0023] Two sets of sampling structures are symmetrically arranged on both sides of the thermal desorption component for sampling.

[0024] In this embodiment, the sampling structure can extract the sample from inside the sample storage tube and send it to the corresponding analytical instrument.

[0025] Each exhaust structure is located outside the sampling structure and connected to the sampling structure to exhaust the gas in the sampling structure.

[0026] In this embodiment, by inserting the sampling structure into the exhaust structure and operating the exhaust structure, the air inside the sampling structure is extracted and discharged, so that the sampling structure is kept in a sub-vacuum state before sampling. This allows the gas in the cavity to be discharged before sampling, avoiding air from affecting the analysis structure and making it easier to use.

[0027] like Figure 2 and Figure 6 As shown, the exhaust structure includes: vacuum tube 4, vacuum shell 5, conical cover 6, vacuum pump 26, sealing structure and auxiliary sampling structure.

[0028] Specifically, one end of the vacuum shell 5 is connected to the vacuum tube 4.

[0029] In this embodiment, the sampling structure can be inserted into the vacuum tube 4, and a vacuum pump 26 can be used to perform a vacuuming operation.

[0030] One end of the conical cover 6 is a first opening, and the other end is a second opening. The inner diameter of the first opening is smaller than the inner diameter of the second opening. The first opening is connected to the other end of the vacuum shell 5.

[0031] In this embodiment, the conical cover 6 can be used to contact sample storage tubes of different sizes.

[0032] The output end of the vacuum pump 26 is equipped with a flexible hose, which is connected to the vacuum tube 4.

[0033] In this embodiment, the vacuum pump 26 is a common device on the market, and its principle and internal structure are mature existing technologies, which will not be described in detail here; at the same time, the model of the vacuum pump 26 is selected according to actual needs, as long as it meets the working conditions.

[0034] A sealing structure is located inside the vacuum shell 5 to seal the first opening.

[0035] In this embodiment, the first opening can be sealed by a sealing structure, which facilitates subsequent vacuuming operations.

[0036] An auxiliary sampling structure is located inside the vacuum tube 4 and connected to the sampling structure to drive the sampling structure to move.

[0037] In this embodiment, the sample storage tube and the sampling structure can be connected by an auxiliary sampling structure.

[0038] like Figure 7 and Figure 8 As shown, the auxiliary sampling structure includes: piston plate 9, moving part 8, first screw 10 and sampling needle 11.

[0039] The piston plate 9 is disposed inside the vacuum tube 4, and the edge of the piston plate 9 is in contact with the inner wall of the vacuum tube 4.

[0040] In this embodiment, the piston plate 9 is made of rubber material. Since the inner diameter of the vacuum tube 4 is larger than the outer diameter of the sampling structure, the piston plate 9 is used to seal the excess inner diameter and ensure that the piston plate 9 does not leak air when it moves.

[0041] The movable component 8 consists of a first round rod and a first ring, with the first round rod fixedly disposed between the piston plate 9 and the first ring.

[0042] In this embodiment, the piston plate 9 can be moved synchronously by pushing the moving part 8.

[0043] The first screw 10 passes through the piston plate 9 and is fixedly connected to the piston plate 9; the first screw 10 has a cavity inside.

[0044] In this embodiment, when the piston plate 9 moves, the sampling structure will move synchronously through the first screw 10; by rotating the sampling structure, the sampling structure can be connected to the first screw 10, and the interior of the first screw 10 can be connected to the sampling structure.

[0045] The interior of the sampling needle 11 is connected to the cavity; the surface of the sampling needle 11 has multiple sets of through holes that are connected to the interior of the sampling needle 11, so that air in the vacuum tube 4 can enter the interior of the sampling needle 11 through the through holes.

[0046] In this embodiment, the movement of the first screw 10 can push the sampling needle 11 to move, so that the sampling needle 11 is inserted into the sample storage tube for auxiliary sampling.

[0047] When sampling is required, the user inserts the sampling structure into the vacuum tube 4 and rotates the sampling structure to engage with the threads on the surface of the first screw 10, thus installing the sampling structure onto the first screw 10. At this time, the user pushes the moving part 8, which drives the piston plate 9 to move. The piston plate 9, through the first screw 10, drives the sampling structure and the sampling needle 11 to move synchronously, so that the sampling needle 11 is inserted into the sample storage tube for auxiliary sampling. After sampling is completed, the user rotates the sampling structure in the opposite direction to disassemble the sampling structure and transfer the sample.

[0048] like Figure 7 and Figure 9 As shown, the sealing structure includes: a worm gear 16, a worm 17, a handwheel 18, multiple sets of sliders 19, multiple sets of connecting parts 20, and multiple sets of sealing parts 21.

[0049] Specifically, one side of the worm gear 16 is slidably connected to the vacuum housing 5; a groove is provided on the other side of the worm gear 16.

[0050] In this embodiment, the vacuum housing 5 can support the rotation of the worm gear 16 by sliding between the worm gear 16 and the vacuum housing 5. An annular groove is provided on the vacuum housing 5, and the annular groove is coaxially arranged with the worm gear 16. A support rod extending from the worm gear 16 is slidably connected to the annular groove, so that when the worm gear 16 rotates, the support rod will slide along the annular groove to achieve support.

[0051] The worm 17 is meshed with the worm wheel 16; the worm 17 passes through the vacuum housing 5 and is rotatably connected to the vacuum housing 5; the axis of the handwheel 18 is fixedly connected to one end of the worm 17.

[0052] In this embodiment, by rotating the handwheel 18, the handwheel 18 can drive the worm gear 17 to rotate, and the worm gear 17 will cause the worm wheel 16 to rotate slowly.

[0053] Each set of sliders 19 is set in a groove and is slidably connected to the worm gear 16 through the groove; one end of each set of connectors 20 is fixedly connected to the end of slider 19 away from the worm gear 16.

[0054] In this embodiment, the connector 20 is U-shaped, with its parallel ends penetrating the vacuum shell 5. The movement direction of the connector 20 is restricted by sliding with the vacuum shell 5. When the worm gear 16 rotates, it will cause multiple sets of sliders 19 and multiple sets of connectors 20 to move simultaneously to the center or to the outside through the groove.

[0055] The edge of each set of seals 21 is fixedly connected to the other end of the connector 20; after multiple sets of seals 21 come into contact, they can block the first opening.

[0056] In this embodiment, the number of seals 21 is greater than one, and can be two, three or four. After multiple sets of seals 21 are connected, a disk will be formed, and the outer diameter of the disk is larger than the inner diameter of the first opening, so as to block the first opening.

[0057] When sealing is required, the user turns the handwheel 18, which drives the worm gear 17 to rotate. The worm gear 17 then drives the worm wheel 16 to rotate slowly. As the worm wheel 16 rotates, the sliding between the groove and the slider 19 causes the slider 19 and the connector 20 to move towards the center simultaneously. The connector 20 drives the sealing element 21 to move, so that multiple sets of sealing elements 21 are connected to form a disc. The disc blocks the first opening, thus achieving a seal.

[0058] like Figure 11 and Figure 12 As shown, the sampling structure includes: sampling tube 7, sealing plate 13, limiting member 12, elastic member 14 and piston member 15.

[0059] One end of the sampling tube 7 is provided with a threaded sleeve; the threaded sleeve is fitted on the outside of the first screw 10 and is threadedly connected to the first screw 10.

[0060] In this embodiment, rotating the sampling tube 7 can drive the threaded sleeve to rotate synchronously; the threads on the inner wall of the threaded sleeve and the threads on the outer wall of the first screw 10 are used to connect the sampling tube 7 and the first screw 10.

[0061] The sealing plate 13 is located inside the sampling tube 7.

[0062] In this embodiment, the outer diameter of the sealing plate 13 is larger than the inner diameter of the threaded sleeve; when the threaded sleeve separates from the first screw 10, the sealing plate 13 will block the threaded sleeve to prevent gas from leaking from the sampling tube 7.

[0063] The limiting member 12 is disposed in the cavity; the limiting member 12 is composed of a second round rod and a second round ring, and the two ends of the second round rod are respectively fixedly connected to the inner wall of the second round ring and the first screw 10.

[0064] In this embodiment, as the threaded sleeve is installed with the first screw 10, the limiting member 12 will contact the sealing plate 13 and push the sealing plate 13 away from the threaded sleeve, thereby creating a gap so that gas can enter and exit.

[0065] The two ends of the elastic element 14 are fixedly connected to the sealing plate 13 and the sampling tube 7 respectively, and are sleeved on the outside of the threaded sleeve.

[0066] In this embodiment, the elastic element 14 is a spring. Currently, the elastic element 14 is in a stretched state. When the sealing plate 13 moves away from the threaded sleeve, the elastic element 14 will be stretched again. The elastic force of the elastic element 14 is greater than the gas pressure difference between the inside and outside.

[0067] The piston component 15 consists of a rubber pad and a handle. The edge of the rubber pad is in contact with the inner wall of the sampling tube 7. The side of the rubber pad away from the sealing plate 13 is fixedly connected to the handle.

[0068] In this embodiment, by pulling the handle, the handle can move the rubber pad, and the sample in the sample storage tube can be drawn into the sampling tube 7 by using the pressure difference.

[0069] During sampling, the sampling tube 7 is first inserted into the vacuum tube 4, so that the threaded sleeve contacts the first screw 10. Then, the threaded sleeve is rotated to connect the sampling tube 7 and the first screw 10 together. Subsequently, the sample storage tube is connected to the sampling tube 7 through the auxiliary sampling structure. During this process, the limiting member 12 contacts the sealing plate 13 and pushes the sealing plate 13 away from the threaded sleeve, thereby creating a gap to allow gas to enter and exit. At the same time, the elastic member 14 is stretched again. Then, the handle is pulled to move the piston member 15. Using the pressure difference, the sample in the sample storage tube is drawn into the sampling tube 7 to complete the sampling. Afterward, the sampling tube 7 is rotated in the opposite direction to remove it. After removal, the elastic member 14 rebounds, causing the sealing plate 13 to block the gas outlet of the threaded sleeve to prevent gas leakage.

[0070] like Figure 11 and Figure 12 As shown, the length of the second circular rod is greater than the length of the threaded sleeve, so that when the threaded sleeve is connected to the first screw 10, the second circular ring can separate the sealing plate 13 and the threaded sleeve.

[0071] In this embodiment, the length of the second round rod is greater than the length of the threaded sleeve, but less than the sum of the lengths of the threaded sleeve and the first screw 10, so that the threaded sleeve and the first screw 10 are in a connected state when the limiting member 12 is not in contact with the sealing plate 13.

[0072] The thermal desorption sealing sampling device also includes: a movable structure; the movable structure is located inside the worktable 1 and is used to move the sampling structure.

[0073] like Figure 1 and Figure 5 As shown, the moving structure includes: two sets of fixing parts 22, two sets of moving nuts 23, two sets of second screws 24, and a dual-output shaft motor 25.

[0074] Specifically, each set of fasteners 22 is installed on the outside of the vacuum tube 4 and is fixedly connected to the vacuum tube 4.

[0075] In this embodiment, the vacuum tube 4 can be moved horizontally by the fixing member 22.

[0076] Both sets of movable nuts 23 are located inside the worktable 1 and are slidably connected to the worktable 1.

[0077] In this embodiment, the movement direction of the movable nut 23 is limited by sliding between the movable nut 23 and the worktable 1.

[0078] Each set of second screws 24 passes through the movable nut 23 and is threadedly connected to the movable nut 23; both ends of the dual output shaft motor 25 are fixedly connected to the adjacent ends of the two sets of second screws 24.

[0079] In this embodiment, by operating the dual-output shaft motor 25, two sets of second screws 24 can be driven to rotate synchronously, and the second screws 24 will cause the moving nut 23 to move horizontally. The dual-output shaft motor 25 is a common device on the market, and its principle and internal structure are mature existing technologies, which will not be described in detail here. At the same time, the model of the dual-output shaft motor 25 is selected according to actual needs, as long as it meets the working conditions.

[0080] like Figure 3 and Figure 4 As shown, the thermal desorption assembly includes: a placement component 2 and an electric heating tube 3.

[0081] The placement component 2 consists of two sets of separable support components, and an arc-shaped notch is provided on the adjacent side of the two sets of support components; the two sets of support components are joined together to form a heating cavity.

[0082] In this embodiment, the sample storage tube can be replaced by separating the two sets of support members.

[0083] The electric heating tube 3 is installed in the support and can heat the sample storage tube after power is applied.

[0084] In this embodiment, the electric heating element 3 is a common device on the market. Its principle and internal structure are existing mature technologies, and will not be described in detail here.

[0085] like Figure 4 As shown, sealing semi-rings are provided at both ends of the support member to seal the heating chamber.

[0086] In this embodiment, the sealing half-ring is made of high-temperature resistant rubber material, which can undergo slight deformation and withstand high temperatures.

[0087] Working principle: When using this thermal desorption sealed sampling device, the user opens the placement part 2, places the sample storage tube into the placement part 2, and starts the electric heating tube 3 to heat the sample storage tube.

[0088] Before sampling, the user inserts the sampling tube 7 into the vacuum tube 4 so that the threaded sleeve contacts the first screw 10. Then, the user rotates the threaded sleeve to connect the sampling tube 7 and the first screw 10 together.

[0089] When sealing is required, the user turns the handwheel 18, which drives the worm gear 17 to rotate. The worm gear 17 then drives the worm wheel 16 to rotate slowly. As the worm wheel 16 rotates, the sliding between the groove and the slider 19 causes the slider 19 and the connector 20 to move towards the center simultaneously. The connector 20 drives the sealing element 21 to move, so that multiple sets of sealing elements 21 are connected to form a disc. The disc blocks the first opening, thus achieving a seal.

[0090] Then, the vacuum pump 26 is started. The vacuum pump 26 will extract and discharge the gas in the vacuum tube 4 and the sampling tube 7 through the hose, so that the sampling structure is kept in a sub-vacuum state before sampling. This allows the gas in the cavity to be discharged before sampling, avoiding air from affecting the analysis structure and making it easier to use.

[0091] Subsequently, the moving part 8 is pushed, which drives the piston plate 9 to move. The piston plate 9 will drive the sampling structure and the sampling needle 11 to move synchronously through the first screw 10, so that the sampling needle 11 is inserted into the sample storage tube for auxiliary sampling.

[0092] During sampling, the sample storage tube is connected to the sampling tube 7 via an auxiliary sampling structure. During this process, the limiting member 12 contacts the sealing plate 13 and pushes the sealing plate 13 away from the threaded sleeve, thereby creating a gap that allows gas to enter and exit. At the same time, the elastic member 14 is stretched again. Then, the handle is pulled, causing the piston member 15 to move. Using the pressure difference, the sample in the sample storage tube is drawn into the sampling tube 7, completing the sampling. Afterward, the sampling tube 7 is rotated in the opposite direction to disassemble it. After disassembly, the elastic member 14 rebounds, causing the sealing plate 13 to block the gas outlet of the threaded sleeve, preventing gas leakage, thus completing the use of the device.

[0093] Although the present invention has been illustrated and described with reference to preferred embodiments, those skilled in the art should understand that various changes in form and detail are possible within the scope of the claims.

Claims

1. A thermal desorption sealed sampling device, characterized in that: include: Workbench (1); A thermal desorption assembly is disposed above the worktable (1) and connected to the worktable (1) for thermal desorption of the sample storage tube; Two sets of sampling structures are symmetrically arranged on both sides of the thermal desorption component for sampling; Two sets of exhaust structures are provided, each set of exhaust structures is located outside the sampling structure and connected to the sampling structure, and is used to exhaust the gas in the sampling structure.

2. The thermal desorption sealed sampling device according to claim 1, characterized in that: The exhaust structure includes: Vacuum tube (4); A vacuum shell (5), one end of which is connected to the vacuum tube (4); A conical cover (6) has a first opening at one end and a second opening at the other end. The inner diameter of the first opening is smaller than the inner diameter of the second opening. The first opening is connected to the other end of the vacuum shell (5). A vacuum pump (26) is provided with a flexible hose at its output end, and is connected to the vacuum tube (4) through the flexible hose; A sealing structure is provided inside the vacuum shell (5) for sealing the first opening; An auxiliary sampling structure is disposed inside the vacuum tube (4) and connected to the sampling structure, and is used to drive the sampling structure to move.

3. The thermal desorption sealed sampling device according to claim 2, characterized in that: The auxiliary sampling structure includes: A piston plate (9) is disposed inside the vacuum tube (4), and the edge of the piston plate (9) is in contact with the inner wall of the vacuum tube (4); The movable part (8) is composed of a first round rod and a first ring, wherein the first round rod is fixedly disposed between the piston plate (9) and the first ring; A first screw (10) passes through the piston plate (9) and is fixedly connected to the piston plate (9); the first screw (10) has a cavity inside; The sampling needle (11) is connected to the cavity inside. The surface of the sampling needle (11) has multiple sets of through holes that are connected to the inside of the sampling needle (11), so that the air in the vacuum tube (4) can enter the interior of the sampling needle (11) through the through holes.

4. The thermal desorption sealed sampling device according to claim 2, characterized in that: The sealing structure includes: A worm gear (16) is slidably connected to the vacuum housing (5) on one side; a groove is provided on the other side of the worm gear (16). The worm (17) meshes with the worm wheel (16); the worm (17) passes through the vacuum housing (5) and is rotatably connected to the vacuum housing (5); Handwheel (18), the axis of which is fixedly connected to one end of the worm (17); Multiple sets of sliders (19), each set of sliders (19) is disposed in the groove and is slidably connected to the worm gear (16) through the groove; Multiple sets of connectors (20), one end of each set of connectors (20) is fixedly connected to the end of the slider (19) away from the worm gear (16); Multiple sets of seals (21), the edge of each set of seals (21) is fixedly connected to the other end of the connector (20); after the multiple sets of seals (21) come into contact, they can block the first opening.

5. The thermal desorption sealed sampling device according to claim 3, characterized in that: The sampling structure includes: A sampling tube (7) is provided with a threaded sleeve at one end; the threaded sleeve is sleeved on the outside of the first screw (10) and is threadedly connected to the first screw (10); A sealing plate (13) is disposed inside the sampling tube (7); A limiting member (12) is disposed in the cavity; the limiting member (12) is composed of a second round rod and a second ring, and the two ends of the second round rod are respectively fixedly connected to the inner wall of the second ring and the first screw (10); The elastic element (14) is fixedly connected at both ends to the sealing plate (13) and the sampling tube (7) respectively, and is sleeved on the outside of the threaded sleeve; The piston component (15) consists of a rubber pad and a handle. The edge of the rubber pad is in contact with the inner wall of the sampling tube (7). The side of the rubber pad away from the sealing plate (13) is fixedly connected to the handle.

6. The thermal desorption sealed sampling device according to claim 5, characterized in that: The length of the second round rod is greater than the length of the threaded sleeve, so that when the threaded sleeve is connected to the first screw (10), the second ring can separate the sealing plate (13) and the threaded sleeve.

7. The thermal desorption sealed sampling device according to claim 2, characterized in that: Also includes: A movable structure is disposed inside the worktable (1) and is used to move the sampling structure.

8. The thermal desorption sealed sampling device according to claim 7, characterized in that: The movable structure includes: Two sets of fasteners (22), each set of fasteners (22) is sleeved on the outside of the vacuum tube (4) and fixedly connected to the vacuum tube (4); Two sets of movable nuts (23) are both located inside the worktable (1) and are slidably connected to the worktable (1); Two sets of second screws (24), each set of second screws (24) passing through the movable nut (23) and threadedly connected to the movable nut (23); A dual-output shaft motor (25) is fixedly connected at both ends to one end of the two sets of second screws (24).

9. The thermal desorption sealed sampling device according to claim 1, characterized in that: The thermal desorption assembly includes: The placement component (2) consists of two sets of separable support components, and an arc-shaped notch is provided on the adjacent side of the two sets of support components; the two sets of support components form a heating cavity after being joined together. An electric heating tube (3) is installed in the support and can heat the sample storage tube after being powered on.

10. The thermal desorption sealed sampling device according to claim 9, characterized in that: The support member has sealing semi-rings at both ends for sealing the heating chamber.

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