Wide variable-pressure environment mass spectrometer composite sampling system and detection method thereof

Abstract

The present invention relates to a wide-variable-pressure environment mass spectrometer composite sampling system and a detection method thereof in the technical field of mass spectrometers, including a capillary, a vacuum tube, a telescopic tube, a vacuum gate valve, a vacuum adapter flange, and an ion source; the two ends of the capillary are respectively denoted as the sampling end and the sample outlet end, the two ends of the vacuum tube are respectively denoted as the head end and the tail end, the sample outlet end enters the cavity of the vacuum tube from the tail end and extends to a predetermined distance outside the head end, and the sampling end is located outside the tail end; the vacuum tube is sleeved inside the telescopic tube, one end of the telescopic tube is fixedly connected to the tail end, the other end of the telescopic tube is docked with one end of the vacuum gate valve, the other end of the vacuum gate valve is docked with an interface of the vacuum adapter flange, and the ion source is arranged inside the vacuum adapter flange. The present invention can simultaneously detect and analyze analytes in a vacuum environment and an atmospheric pressure environment, and can also realize the individual test of analytes in a vacuum environment or an atmospheric pressure environment, significantly improving the detection effect.

Description

Technical Field

[0001] The present invention relates to the technical field of mass spectrometers, and specifically, to a composite sampling system for a mass spectrometer in a wide variable pressure environment and a detection method thereof. Background Art

[0002] The mass spectrometer system has a fast analysis speed, high detection sensitivity, requires a small amount of sample for detection, and can be applied to the detection and analysis of most compounds. It has a wide range of applications in fields such as residual gas analysis, public safety, and environmental monitoring. Due to the non-specificity of its detection, when the analysis chamber of the mass spectrometer system is in a non-vacuum environment, all substances in the chamber will be ionized and detected as analytes, which will cause the target analyte to be submerged in the noise of other substances, making it difficult to achieve sample analysis and imposing a great burden on the subsequent electrical signal detector and the like. Therefore, the mass spectrometer must work in a high-vacuum environment. This makes the sampling system of the mass spectrometer very crucial. The selection of the sampling system is directly related to the substance components that the mass spectrometer can detect and its application range.

[0003] When dealing with the detection requirements in a vacuum environment, such as the analysis of residual gas in a vacuum tank, etc., the sampling system of the mass spectrometer needs to connect the vacuum in its own chamber with the vacuum in the vacuum tank and enable the residual gas in the vacuum tank to enter the ion source for ionization and then analysis. Residual gas mass spectrometers are mostly used in such requirements. Since the vacuum tank itself has a good vacuum degree, the vacuum system required by the mass spectrometer can be omitted. When dealing with the detection requirements in an atmospheric pressure environment, a vacuum-atmospheric pressure interface is needed to introduce the analyte in the atmospheric pressure into the vacuum system of the mass spectrometer. A common vacuum-atmospheric pressure interface is a thin film sampling interface. The thin film sampling interface uses a selective semi-permeable membrane at the sampling port of the mass spectrometer to introduce the analyte in the atmospheric pressure environment, but it is easily contaminated by the dirty environmental background and produces incorrect results.

[0004] Due to the limitations of the sampling system, a single mass spectrometer can only detect samples in a single environment. Even if it can be replaced by modules, it cannot detect samples in different environments simultaneously, greatly reducing the detection efficiency of the mass spectrometer and restricting the application range of various mass spectrometers.

[0005] After retrieval, there is no multi-purpose mass spectrometer in the prior art. Summary of the Invention

[0006] Aiming at the deficiencies in the prior art, the purpose of the present invention is to provide a composite sampling system for a mass spectrometer in a wide variable pressure environment and a detection method thereof.

[0007] According to a composite sampling system for a mass spectrometer in a wide variable pressure environment provided by the present invention, it includes a capillary, a vacuum tube, a telescopic tube, a vacuum gate valve, a vacuum adapter flange, and an ion source;

[0008] The two ends of the capillary are respectively denoted as the sample injection end and the sample output end. The two ends of the vacuum tube are respectively denoted as the head end and the tail end. The sample output end enters the cavity of the vacuum tube from the tail end and extends a predetermined distance outside the head end, and the sample injection end is located outside the tail end.

[0009] The telescopic tube is a tube body that can be telescoped along the axial direction. The vacuum tube is sleeved inside the telescopic tube. One end of the telescopic tube is fixedly connected to the tail end, and the other end of the telescopic tube is docked with one end of the vacuum gate valve. The other end of the vacuum gate valve is docked with an interface of the vacuum adapter flange. The ion source is placed inside the vacuum adapter flange. The vacuum adapter flange is a vacuum flange three-way interface structure, and the other two interfaces of the vacuum adapter flange are respectively used to connect the mass spectrometer and the vacuum tank.

[0010] After compressing the telescopic tube by a predetermined distance, the head end passes through the vacuum gate valve and enters the vacuum adapter flange, and the sample injection end is docked with the ion source. After stretching the telescopic tube by a predetermined distance, the vacuum tube retracts and resets with the telescopic tube, and the vacuum gate valve can be freely closed.

[0011] In some embodiments, the telescopic tube includes a first support tube, a second support tube, and a corrugated tube. The corrugated tube is clamped between the first support tube and the second support tube. The first support tube is fixedly connected to the tail end, and the second support tube is connected to the vacuum gate valve.

[0012] In some embodiments, the capillary is fixed in the vacuum tube through a clamping assembly. The clamping assembly includes a first ferrule, an outer sleeve tube, and a second ferrule and a ferrule press head arranged inside the outer sleeve tube. The first ferrule is arranged inside the head end, and the ferrule press head is used to press and fix the second ferrule.

[0013] A connection ring is formed on the outer peripheral surface of the vacuum tube at the tail end. The two axial ends of the connection ring are respectively connected to the telescopic tube and the outer sleeve tube. The first ferrule and the second ferrule are respectively used to clamp the tube body of the capillary.

[0014] In some embodiments, the ion source is an end-face grid ion source. A middle through hole is provided on the grid electrode of the ion source. A guide is installed inside the middle through hole. The guide is funnel-shaped. The port of the guide facing the grid electrode is adapted to the aperture of the middle through hole, and the opening of the guide facing the sample injection end is trumpet-shaped.

[0015] In some embodiments, the capillary is a quartz capillary, and a capillary protection tube is sleeved outside the capillary.

[0016] In some embodiments, a driving component is further included. The driving component includes a first support plate, a second support plate, a third support plate, and a driving screw.

[0017] The first support plate is sleeved on the connecting ring. The third support plate is sleeved on the tube body of the telescopic tube close to the vacuum gate valve. The second support plate is sleeved on the tube body of the telescopic tube and is located between the first support plate and the second support plate. One end of the driving screw sequentially passes through the first support plate and the second support plate and then is connected to the third support plate. The driving screw is threadedly connected to the first support plate. By rotating the driving screw, the third support plate moves in a manner of approaching or departing from the first support plate, thereby realizing the contraction or stretching of the telescopic tube.

[0018] The present invention further provides a composite sample injection detection method for a wide variable pressure environment mass spectrometer. Using the wide variable pressure environment mass spectrometer composite sample injection system, the other two ports of the vacuum adapter flange are respectively connected to a mass spectrometer and a vacuum tank, including vacuum environment sample detection, atmospheric pressure environment sample detection, and simultaneous sample detection under vacuum and atmospheric pressure environments.

[0019] In some embodiments, the steps of the atmospheric pressure environment detection are as follows: Open the vacuum gate valve, close the connection channel between the vacuum adapter flange and the vacuum tank through a blind plate, rotate the driving screw to drive the third support plate to move towards the first support plate, the telescopic tube is compressed, the first end passes through the cavity of the vacuum gate valve and enters a predetermined position inside the vacuum adapter flange, the sample outlet end is docked with the ion source, a vacuum is established, after sampling through the sample inlet end and discharging from the sample outlet end and feeding it into the ion source, the atmospheric pressure environment sample detection is completed by the mass spectrometer.

[0020] In some embodiments, the steps of the vacuum environment sample detection are as follows: Rotate the driving screw to drive the third support plate to move away from the first support plate, the telescopic tube is stretched, the first end withdraws from inside the vacuum adapter flange until the sample outlet end is at a position where it does not affect the closed state of the vacuum gate valve and then stops. Close the vacuum gate valve, open the channel between the vacuum adapter flange and the vacuum tank, and perform vacuum environment sample detection by the mass spectrometer.

[0021] In some embodiments, the steps for simultaneously detecting samples in a vacuum and atmospheric pressure environment are as follows: Open the vacuum gate valve, and at the same time, open the channel between the vacuum adapter flange and the vacuum tank. Rotate the drive screw to drive the third support plate to move towards the first support plate. The telescopic tube is compressed, and the head end passes through the cavity of the vacuum gate valve and enters a predetermined position inside the vacuum adapter flange. The sample outlet end is docked with the ion source. After sampling through the sample inlet end and discharging the sample from the sample outlet end and sending it into the ion source, at the same time, the residual gas in the vacuum tank enters the ion source, and the simultaneous detection of samples in the atmospheric pressure environment and the vacuum environment is completed through the mass spectrometer.

[0022] Compared with the prior art, the present invention has the following beneficial effects:

[0023] 1. The wide variable pressure environment mass spectrometer composite sampling system provided in this embodiment can simultaneously detect and analyze analytes in a vacuum environment and an atmospheric pressure environment through the optimized design of structural components. It can also realize the individual testing of analytes in a vacuum environment or an atmospheric pressure environment, significantly improving the detection effect, expanding the application range of a single mass spectrometer, and improving the applicability and cost performance of the instrument.

[0024] 2. The wide variable pressure environment mass spectrometer composite sampling system provided in this embodiment has a simple structure and convenient operation by setting a driving component for driving the telescopic tube, improving the operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] By reading the following detailed description of non-limiting embodiments with reference to the accompanying drawings, other features, objects, and advantages of the present invention will become more apparent:

[0026] Figure 1 It is a schematic structural diagram of the wide variable pressure environment mass spectrometer composite sampling system of the present invention;

[0027] Figure 2 It is a schematic sectional view of the wide variable pressure environment mass spectrometer composite sampling system of the present invention;

[0028] Figure 3 It is a schematic structural diagram of the capillary tube fixed by the clamping assembly of the present invention;

[0029] Figure 4 It is a schematic structural diagram of the ion source of the present invention;

[0030] Figure 5 It is a mass spectrum diagram collected by the simultaneous detection of samples in the vacuum and atmospheric pressure environments of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0031] The present invention will be described in detail below in conjunction with specific embodiments. The following embodiments will help those skilled in the art to further understand the present invention, but do not limit the present invention in any form. It should be noted that for those of ordinary skill in the art, without departing from the concept of the present invention, several changes and improvements can still be made. These all belong to the protection scope of the present invention.

[0032] Embodiment 1

[0033] Embodiment 1 of the present invention provides a composite sample injection system for a wide variable pressure environment mass spectrometer, specifically providing a system that can achieve sample detection in an atmospheric pressure environment, sample detection in a vacuum environment, and simultaneous detection of samples in an atmospheric pressure environment and a vacuum environment, as Figures 1-5 shown, mainly including a capillary 1, a vacuum tube, a telescopic tube 3, a vacuum gate valve 4, a vacuum adapter flange 5, and an ion source 6.

[0034] The capillary 1 is used to connect the vacuum chamber and the atmospheric environment. The small inner diameter of the capillary 1 maintains the vacuum environment in the mass spectrometer chamber, and the analytes in the environment are introduced through the internal and external pressure difference. In some embodiments, the capillary 1 is made of quartz material, and the inner diameter of the quartz capillary can be made smaller. In some embodiments, the outer diameter of the capillary 1 made of quartz material is 0.365 mm, the inner diameter is 0.05 mm, the length is 2 m, and the pumping speed of the used vacuum system is 250 L / s, so that the ultimate vacuum degree in the atmospheric pressure detection mode can reach 8.44E-5 Pa. The two ends of the capillary 1 are respectively an injection end 11 and an extraction end 12. The vacuum tube is a tube body with a hollow inner cavity, and its two ends are respectively a head end 21 and a tail end 22. The extraction end 12 of the capillary 1 enters the inner cavity of the vacuum tube from the tail end 22 and penetrates out a predetermined distance from the head end 21. In some embodiments, the distance that the end of the extraction end 12 exposes from the head end 21 is 10-15 mm, which is convenient for docking with the ion source 6 and improves the injection rate. In some embodiments, the fixed connection between the capillary 1 and the vacuum tube is realized through the clamping assembly 7. The clamping assembly 7 mainly includes a first ferrule 71, a second ferrule 72, a ferrule press head 73 and an outer sleeve 74. The first ferrule 71 is arranged in the inner cavity of the head end 21 of the vacuum tube, and the tube body of the capillary 1 close to the extraction end 12 is clamped and fixed in the first ferrule 71. In some embodiments, the structure of the first ferrule 71 is a conical tube arranged on a support plate, and the extraction end 12 of the capillary 1 penetrates out from the first ferrule 71, and the capillary 1 can be effectively fixed through the clamping structure of the conical tube. The second ferrule 72 and the ferrule press head 73 are arranged in the outer sleeve 74, and the ferrule press head 73 clamps the second ferrule 72 to ensure its stability. One end of the outer sleeve 74 is docked with the vacuum tube. In some embodiments, the end of the outer sleeve 74 is a flange-like structure, and a connecting ring 23 is formed on the outer peripheral surface of the tail end 22 of the vacuum tube. The flange-like end of the outer sleeve 74 is fixedly connected with the connecting ring 23 through bolts, which improves the assembly efficiency. After the outer sleeve 74 is fixedly connected with the vacuum tube, the injection end 11 penetrates out from the outer sleeve 74, and the tube body of the capillary 1 close to the tail end 22 is clamped on the second ferrule 72. Since the length of the tube body of the capillary 1 located outside the outer sleeve 74 is relatively long, the ferrule press head 73 can effectively improve the firmness of the second ferrule 72 and ensure the support degree for the capillary 1. In some embodiments, a capillary protection tube 10 is sleeved outside the capillary 1 to protect the capillary 1. In some embodiments, the first ferrule 71 is a stainless steel ferrule, and the second ferrule is a graphite ferrule.

[0035] The telescopic tube 3 is a tube structure capable of axial telescoping. The telescopic tube 3 is sleeved outside the vacuum tube. The two ends of the telescopic tube 3 are respectively denoted as the fixed end and the movable end. The fixed end is connected to the tail end 22 and remains relatively stationary, and the movable end is in a free state relative to the head end 21 and can move axially. When the telescopic tube 3 is compressed, the movable end retreats relative to the head end 21, causing the head end 21 to be gradually exposed. When the telescopic tube 3 is stretched, the movable end gradually moves towards the head end 21 and causes the head end 21 to enter the tube body of the telescopic tube 3. In the above, the so-called movement refers to the relative movement between the telescopic tube 3 and the head end 21. In some embodiments, the telescopic tube 3 is connected by a first supporting tube 31, a second supporting tube 32, and a corrugated tube 33 clamped between the first supporting tube 31 and the second supporting tube 32. The first supporting tube 31 is connected to the connecting ring 23, and the second supporting tube 32 is connected to the vacuum gate valve 4. In some embodiments, the connecting ring 23 is provided with a ring groove, and the first supporting tube 31 is inserted into the ring groove and fixedly connected. The end of the second supporting tube 32 forms a flange-like structure and is fixedly connected to the flange connecting portion of the vacuum gate valve 4 by bolts. The first supporting tube 31 and the second supporting tube 32 are used to support the corrugated tube 33 in the middle, and at the same time can prevent the corrugated tube 33 from bending in the radial direction when the corrugated tube 33 is compressed, resulting in the capillary 1 being unable to enter the ion source 6 normally or even being damaged.

[0036] The vacuum gate valve 4 is a valve structure body, mainly used to control the opening and closing of the passage, and the cavity inside it can allow the tube body of the vacuum tube to pass through. After one end of the vacuum gate valve 4 is fixedly and hermetically connected to the second supporting tube 32, the other end of the vacuum gate valve 4 is hermetically butted with an interface of the vacuum adapter flange 5. The ion source 6 is installed in the cavity of the vacuum adapter flange 5. The vacuum adapter flange 5 is a three-way structure body, one of its interfaces is hermetically connected to the other end of the vacuum gate valve 4, and the remaining two interfaces are respectively used for hermetically connecting the mass spectrometer and the vacuum tank. The mass spectrometer analyzes the sample through the ion source 6, and the vacuum tank provides the residual gas sample in the vacuum environment. In some embodiments, as shown in Figure 3 shown, the ion source 6 is an improved end-face grid ion source. A middle through-hole 601 is opened on the grid electrode 61 of the ion source, and a ceramic guide 9 is installed and connected to the middle through-hole 601. The ceramic guide 9 is a funnel-shaped body. The opening of the guide 9 facing the grid electrode 61 is adapted to the aperture of the middle through-hole 601, and the opening of the guide 9 facing the sample outlet end 12 is trumpet-shaped and has a larger opening, which is convenient for the sample inlet end 12 to smoothly enter the ion source end during the detection of samples in the atmospheric pressure environment, thereby improving the sensitivity of the atmospheric pressure detection. The central axes of the ceramic guide 9, the sample inlet end 12, the vacuum tube, the first ferrule 71, and the second ferrule 72 are basically coincident to ensure that the sample outlet end 12 can correctly extend into the ceramic guide 9.

[0037] The working principle of the wide variable pressure environment mass spectrometer composite sampling system provided in this embodiment is:

[0038] Detection of samples in atmospheric pressure environment: Open the vacuum gate valve 4 and close the connection channel between the vacuum adapter flange 5 and the vacuum tank. Compress the telescopic tube 3 so that the first end 21 passes through the vacuum gate valve 4 and enters the vacuum adapter flange 5. The sample outlet end 12 is docked with the ceramic guide 9. Establish a vacuum. After sampling through the sample inlet end 11 and discharging the sample from the sample outlet end 12 and sending it into the ion source 6, the detection of samples in the atmospheric pressure environment is completed by the mass spectrometer. Establishing a vacuum means that the mass spectrometer is improved and a vacuum flange interface is designed to be connected to an external vacuum pump group, thereby establishing a required vacuum environment. The mass spectrometer is a residual gas mass spectrometer.

[0039] Detection of samples in vacuum environment: Stretch the telescopic tube 3. Stop when the first end 21 withdraws from the vacuum adapter flange 5 until the sample outlet end 12 is in a position that does not affect the closing of the vacuum gate valve 4. Close the vacuum gate valve 4. Open the channel between the vacuum adapter flange 5 and the vacuum tank. Detect the residual gas sample in the vacuum tank in the vacuum environment through the mass spectrometer.

[0040] Simultaneous detection of samples in vacuum and atmospheric pressure environments: Open the vacuum gate valve 4 and the channel between the vacuum adapter flange 5 and the vacuum tank. Compress the telescopic tube 3. The first end 21 passes through the cavity of the vacuum gate valve 4 and enters a predetermined position in the vacuum adapter flange 5. The sample outlet end 12 enters the ceramic guide 9. Establish a vacuum system. After sampling through the sample inlet end 11 and discharging the sample from the sample outlet end 12, the sample is sent into the ion source 6. At the same time, the residual gas in the vacuum tank enters the ion source 6. The simultaneous detection of samples in the atmospheric pressure environment and the vacuum environment is completed by the mass spectrometer.

[0041] The wide variable pressure environment mass spectrometer composite sampling system provided by this embodiment can detect and analyze analytes in both vacuum environment and atmospheric pressure environment through the optimized design of structural components, and can also realize the individual testing of analytes in vacuum environment or atmospheric pressure environment, significantly improving the detection effect, expanding the application range of a single mass spectrometer, and improving the applicability and cost performance of the instrument.

[0042] Embodiment 2

[0043] This Embodiment 2 is formed on the basis of Embodiment 1. By setting a driving component for driving the telescopic tube, the structure is simple, the operation is convenient, and the operation efficiency is improved. Specifically:

[0044] Such as Figures 1-4As shown in the figure, the driving component 8 is used to drive the stretching and shrinking of the telescopic tube 3. The driving component 8 includes a first support plate 81, a second support plate 82, a third support plate 84, and a driving screw 84. A through hole is provided in the middle of the first support plate 81. The connecting ring 23 is sleeved in the through hole of the first support plate 81 and is tightly connected. The tight connection can be an interference fit connection or can be connected by means such as welding, so that the two form a tight connection. The third support plate 83 is sleeved on the tube body of the telescopic tube 3 close to the moving end 32, and the two are also tightly connected. The second support plate 82 is sleeved on the middle tube body of the telescopic tube 3. The second support plate 82 is slidably connected to the telescopic tube 3. The second support plate 82 is located between the first support plate 81 and the third support plate 83. One end of the driving screw 84 passes through the first support plate 81 and the second support plate 82 in sequence, and its end is fixedly connected to the third support plate 83. The connection between the driving screw 84 and the first support plate 81 is a threaded connection, and the driving screw 84 and the second support plate 82 are slidably connected.

[0045] Taking manual driving as an example, a driving handle 85 is installed at the other end of the driving screw 84. By rotating the driving screw 84 through the driving handle 85, the third support plate 83 is pushed away from the first support plate 81 or pulled close to the first support plate 81 through the driving screw 84, thereby realizing the stretching and compression of the telescopic tube 3. The structure is simple and the operation is convenient.

[0046] Embodiment 3

[0047] This Embodiment 3 is a composite sampling detection method for a wide variable pressure environment mass spectrometer formed on the basis of Embodiment 1 or 2, and adopts the wide variable pressure environment mass spectrometer composite sampling system described in Embodiment 1 or 2. At this time, the other two ports of the vacuum adapter flange (5) are respectively connected to the mass spectrometer and the vacuum tank, wherein the mass spectrometer is a self-contained vacuum system.

[0048] The composite sampling detection method for a wide variable pressure environment mass spectrometer provided in this embodiment includes a vacuum environment sample detection method, an atmospheric pressure environment sample detection method, and a method for simultaneously detecting samples under vacuum and atmospheric pressure environments.

[0049] The steps for detecting in the atmospheric pressure environment are as follows: Open the vacuum gate valve 4, close the connection channel between the vacuum adapter flange 51 and the vacuum tank through the blind plate, rotate the driving screw 84 to drive the third support plate 83 to move towards the first support plate 81, the telescopic tube 3 is compressed, the first end 21 passes through the cavity of the vacuum gate valve 4 and then enters a predetermined position inside the vacuum adapter flange 5, the sample outlet end 12 is docked with the ion source 6, a vacuum is established, after sampling through the sampling end 11 of the capillary 1 and exiting from the sample outlet end 12 and then sending it into the ion source 6, the detection of samples in the atmospheric pressure environment is completed by the mass spectrometer.

[0050] The steps for detecting a sample in a vacuum environment are as follows: Rotate the drive screw 84 to drive the third support plate 83 to move away from the first support plate 81. The telescopic tube 3 is stretched, and the head end 21 withdraws from the vacuum adapter flange 5 until the sample outlet end 12 is at a position where it does not affect the closed state of the vacuum gate valve 4, and then stop. Close the vacuum gate valve 4, open the channel between the vacuum adapter flange 5 and the vacuum tank, and perform the detection of the sample in the vacuum environment through the mass spectrometer.

[0051] The steps for simultaneously detecting samples in vacuum and atmospheric pressure environments are as follows: Open the vacuum gate valve 4, and at the same time open the channel between the vacuum adapter flange 5 and the vacuum tank. Rotate the drive screw 84 to drive the third support plate 83 to move towards the first support plate 81. The telescopic tube 3 is compressed, and the head end 21 passes through the cavity of the vacuum gate valve 4 and then enters a predetermined position inside the vacuum adapter flange 5. The sample outlet end 12 is docked with the ion source 6. Sample through the sample inlet end 11 of the capillary 1 and exit from the sample outlet end 12 and then send it into the ion source 6. At the same time, the residual gas in the vacuum tank enters the ion source 6, and the simultaneous detection of samples in atmospheric pressure and vacuum environments is completed through the mass spectrometer. As Figure 5 shown, it is the mass spectrum collected for the simultaneous detection of samples in vacuum and atmospheric pressure environments.

[0052] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc. is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation to the present application.

[0053] The specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the above specific embodiments, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Without conflict, the embodiments of the present application and the features in the embodiments can be combined arbitrarily with each other.

Claims

1. A composite sampling system for a mass spectrometer in a wide variable pressure environment, characterized in that, it includes a capillary, a vacuum tube, a telescopic tube, a vacuum gate valve, a vacuum adapter flange, and an ion source; The two ends of the capillary are respectively denoted as the sampling end and the sample outlet end. The two ends of the vacuum tube are respectively denoted as the head end and the tail end. The sample outlet end enters the cavity of the vacuum tube from the tail end and extends a predetermined distance outside the head end, and the sampling end is located outside the tail end; The telescopic tube is a tube body that can be telescoped along the axial direction. The vacuum tube is sleeved inside the telescopic tube. One end of the telescopic tube is fixedly connected to the tail end, and the other end of the telescopic tube is docked with one end of the vacuum gate valve. The other end of the vacuum gate valve is docked with an interface of the vacuum adapter flange. The ion source is placed inside the vacuum adapter flange. The vacuum adapter flange is a vacuum flange tee interface structure, and the other two interfaces of the vacuum adapter flange are respectively used to connect to a mass spectrometer and a vacuum tank; After compressing the telescopic tube by a predetermined distance, the head end passes through the vacuum gate valve and enters the vacuum adapter flange, and the sample outlet end is docked with the ion source; after stretching the telescopic tube by a predetermined distance, the vacuum tube retracts and resets with the telescopic tube, and the vacuum gate valve can be freely closed.

2. The composite sampling system for a mass spectrometer in a wide variable pressure environment according to claim 1, characterized in that, The telescopic tube includes a first support tube, a second support tube, and a corrugated tube. The corrugated tube is clamped between the first support tube and the second support tube. The first support tube is fixedly connected to the tail end, and the second support tube is connected to the vacuum gate valve.

3. The composite sampling system for a mass spectrometer in a wide variable pressure environment according to claim 1, characterized in that, The capillary is fixed in the vacuum tube through a clamping assembly. The clamping assembly includes a first ferrule, an outer sleeve tube, and a second ferrule and a ferrule press head arranged inside the outer sleeve tube. The first ferrule is arranged inside the head end, and the ferrule press head is used to press and fix the second ferrule; A connection ring is formed on the outer peripheral surface of the vacuum tube at the tail end. The two axial ends of the connection ring are respectively connected to the telescopic tube and the outer sleeve tube. The first ferrule and the second ferrule are respectively used to clamp the tube body of the capillary.

4. The composite sampling system for a mass spectrometer in a wide variable pressure environment according to claim 1, characterized in that, The ion source is an end face grid ion source. A middle through hole is provided on the grid electrode of the ion source, and a guide is installed in the middle through hole. The guide is in a funnel shape. The port of the guide facing the grid electrode is adapted to the aperture of the middle through hole, and the opening of the guide facing the sampling end is in a horn shape.

5. The composite sampling system for a mass spectrometer in a wide variable pressure environment according to claim 1, characterized in that, The capillary is a quartz capillary, and a capillary protection tube is sleeved outside the capillary.

6. The composite sampling system for a mass spectrometer in a wide variable pressure environment according to any one of claims 1-5, characterized in that, It further includes a driving assembly. The driving assembly includes a first support plate, a second support plate, a third support plate, and a driving screw; A connecting ring is formed on the outer peripheral surface of the vacuum tube at the tail end; The first support plate is sleeved on the connecting ring, the third support plate is sleeved on the tube body of the telescopic tube close to the vacuum gate valve, the second support plate is sleeved on the tube body of the telescopic tube and is located between the first support plate and the second support plate. One end of the driving screw sequentially passes through the first support plate and the second support plate and then is connected to the third support plate. The driving screw is threadedly connected to the first support plate. By rotating the driving screw, the third support plate moves in a manner of approaching or departing from the first support plate, thereby realizing the contraction or stretching of the telescopic tube.

7. A composite sampling detection method for a mass spectrometer in a wide variable pressure environment, characterized in that The composite sampling system for a mass spectrometer in a wide variable pressure environment as described in claim 6 is adopted. The other two ports of the vacuum adapter flange are respectively connected to a mass spectrometer and a vacuum tank, including vacuum environment sample detection, atmospheric pressure environment sample detection, and simultaneous sample detection in vacuum and atmospheric pressure environments.

8. The composite sampling detection method for a mass spectrometer in a wide variable pressure environment according to claim 7, characterized in that The steps of the atmospheric pressure environment detection are as follows: Open the vacuum gate valve, close the connection channel between the vacuum adapter flange and the vacuum tank through a blanking plate, rotate the driving screw to drive the third support plate to move towards the first support plate, the telescopic tube is compressed, the head end passes through the cavity of the vacuum gate valve and then enters a predetermined position inside the vacuum adapter flange, the sample outlet end is docked with the ion source, a vacuum is established, after sampling through the sample inlet end and discharging from the sample outlet end and then feeding it into the ion source, the atmospheric pressure environment sample detection is completed through the mass spectrometer.

9. The composite sampling detection method for a mass spectrometer in a wide variable pressure environment according to claim 7, characterized in that The steps of the vacuum environment sample detection are as follows: Rotate the driving screw to drive the third support plate to move away from the first support plate, the telescopic tube is stretched, the head end withdraws from inside the vacuum adapter flange until the sample outlet end is located at a position that does not affect the closed state of the vacuum gate valve and then stops. Close the vacuum gate valve, open the channel between the vacuum adapter flange and the vacuum tank, and perform vacuum environment sample detection through the mass spectrometer.

10. The composite sampling detection method for a mass spectrometer in a wide variable pressure environment according to claim 7, characterized in that The steps of the simultaneous detection of samples in vacuum and atmospheric pressure environments are as follows: Open the vacuum gate valve, simultaneously open the channel between the vacuum adapter flange and the vacuum tank, rotate the driving screw to drive the third support plate to move towards the first support plate, the telescopic tube is compressed, the head end passes through the cavity of the vacuum gate valve and then enters a predetermined position inside the vacuum adapter flange, the sample outlet end is docked with the ion source, after sampling through the sample inlet end and discharging from the sample outlet end and then feeding it into the ion source, at the same time, the residual gas in the vacuum tank enters the ion source, and the simultaneous detection of samples in atmospheric pressure and vacuum environments is completed through the mass spectrometer.

Images