Gas mixing interface device

Abstract

The invention provides a gas mixing interface device, and relates to the technical field of laser isotope analysis testing, the gas mixing interface device comprises a metering pipe and a telescopic corrugated pipe, the metering pipe is connected with the telescopic corrugated pipe through a first connecting pipeline; a first branch is arranged on the first connecting pipeline, one end of the first branch is connected with the first connecting pipeline, and the other end of the first branch is connected with a negative pressure pump. According to the gas mixing interface device provided by the invention, the sample gas quantity can enter the telescopic corrugated pipe after being accurately metered by the metering pipe, and the diluted gas quantity can also enter the telescopic corrugated pipe after being accurately metered by the metering pipe, so that the mixing ratio of the two gases is accurate and stable under the condition that the sample gas quantity is continuously changed, and the gas mixing efficiency is improved. Meanwhile, the mixing ratio with reference gas can be kept consistent; and two gases in the telescopic corrugated pipe can be quickly, fully and uniformly mixed through stretching and retracting of the telescopic corrugated pipe, so that the mixing efficiency of the gases is improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser isotope analysis testing, and particularly to a gas mixing interface device. BACKGROUND

[0002] Compared with traditional mass spectrometry testing technology, laser isotope analysis testing technology has the advantages of low cost, small size, low operating cost, and wide application scenarios, and has developed rapidly and been applied in the past decade. Laser isotope analyzers were initially mainly used to test the isotopic ratio changes of trace gases in the atmosphere. With the development of spectral technology, the testing precision of laser isotope analyzers is comparable to that of mass spectrometers, and many applications begin to use laser isotope analyzers in combination with solid sample pretreatment and preparation devices, so as to realize the testing and analysis of isotopic content in different types of solid samples by using laser spectral technology.

[0003] Solid sample pretreatment and preparation devices (generally including elemental analyzers, TOC analyzers, carbonate acidification devices, high-temperature cracking devices, etc.) can convert soil, plant, rock, and other samples into pure CO2, CH4, H2O, NO2, and other gases, and the testing object of a laser isotope analyzer is generally a mixed gas with atmospheric proportion. Therefore, a gas mixing interface device must be provided between the solid sample preparation device and the laser isotope analyzer, for mixing the pure target gas (CO2, CH4, H2O, NO2, etc.) generated by the solid sample preparation device and the dilution gas (generally N2 or zero gas) in a specific proportion, and then the mixed gas enters the laser isotope analyzer for isotopic testing and analysis.

[0004] The existing laser isotope analyzer gas mixing interface device is mainly designed in two types. The first type is composed of a target gas and dilution gas interface, a three-way valve, and two metal mixing bottles connected by a stainless steel pipe. The target gas and the dilution gas are introduced through their respective interfaces, mixed through the three-way valve, and then enter the first metal mixing bottle, and then enter the second metal mixing bottle, so as to realize the full mixing and pressure stabilization of the two gases. Finally, the mixed gas enters the laser isotope analyzer for testing from the end of the second metal bottle. The second type is composed of a target gas interface, a dilution gas interface, a gas flow meter, and a mixed gas bag. The target gas and the dilution gas enter the mixed gas bag through the interfaces, and the target gas flow is controlled by the gas flow meter. The amount of target gas entering is controlled by the gas flow meter to control the mixing ratio. The two gases need to be mixed in the gas bag and stand still for more than 40 minutes to achieve full mixing. Finally, the mixed gas enters the laser isotope analyzer for testing and analysis from the end of the gas bag.

[0005] The existing two technical solutions mainly have the following shortcomings: 1) poor control accuracy of mixing ratio. The accurate mixing ratio mainly includes two aspects: firstly, the mixing ratio of each solid sample gas should be kept as stable as possible; and secondly, the mixing ratio of the sample gas and the reference gas (generally, a cylinder gas with a known mixing ratio) should be infinitely close. The accurate mixing ratio is a guarantee for the data quality of the later laser isotope analysis. However, the properties and isotope contents of different solid samples are quite different, and the amount of target gas produced by each sample in the preparation system will change constantly. The existing mixing device cannot automatically adjust the amount of dilution gas according to the change of the amount of target gas produced by the sample preparation system, and thus cannot ensure the accuracy and stability of gas mixing, nor can it match the mixing ratio with the reference gas. It only simply completes the mixing of the two gases, which directly affects the accuracy of the final test data of the laser isotope analyzer. 2) A single sample cannot be tested multiple times. Multiple repetitive tests on a single sample mixed gas can effectively remove the memory effect and greatly improve the test accuracy. As described above, since the amount of target gas produced in the solid sample preparation system is uncertain, the amount of sample mixed gas is also constantly changing, and some mixed gas can only be tested once, while some sample mixed gas can be repeatedly tested 4-5 times. Since the existing two mixing interface devices cannot accurately measure the amount of gas, a sample can only be tested once regardless of the amount of sample gas, and multiple tests on a single sample cannot be realized to improve the data quality. 3) Low gas measurement rate. The existing two technical solutions have a large amount of gas remaining in the mixing device (mainly in the metal bottle or gas bag), and most of the mixed gas cannot enter the laser isotope analyzer, which makes it impossible to test trace samples or low-content samples by the laser isotope analyzer. 4) Low mixing efficiency. The target gas and the dilution gas must be fully mixed to avoid isotope fractionation caused by uneven gas mixing. The first existing technical solution solves the problem of full mixing through two secondary mixing of metal bottles, which is easy to produce a mixing dead volume. The second solution achieves full mixing by waiting for a long time, which consumes a lot of time and affects the test efficiency. SUMMARY

[0006] The purpose of the present application is to provide a gas mixing interface device to solve the technical problems of poor accuracy, instability and low efficiency of gas mixing in front of a laser isotope analyzer, and to alleviate the high gas residue, realize multiple repetitive tests on a single sample, and thus effectively improve the test accuracy of the laser isotope analyzer.

[0007] The present application provides a gas mixing interface device, comprising a metering pipe and a telescopic bellows, the metering pipe being connected with the telescopic bellows through a first connecting pipeline; The metering pipe has a first connecting end, a second connecting end, a third connecting end and a fourth connecting end, the first connecting end is used for connecting with a dilution gas system, the second connecting end is used for connecting with a sample preparation device, the third connecting end is equipped with a high-pressure sensor, and the fourth connecting end is used for connecting with a first connecting pipeline; A first electromagnetic valve is arranged at the first connecting end, and a second electromagnetic valve is arranged at the second connecting end; a first branch is arranged on the first connecting pipeline, one end of the first branch is connected with the first connecting pipeline, and the other end is connected with a negative pressure pump; a third electromagnetic valve is arranged on the first branch. A fourth electromagnetic valve is arranged on the first connecting pipeline, and the fourth electromagnetic valve is arranged in an upstream direction of the telescopic bellows; a fifth electromagnetic valve is arranged in a downstream direction of the telescopic bellows.

[0008] In an optional embodiment, a low-pressure sensor is further arranged on the first connecting pipeline. In an optional embodiment, a second connecting pipeline is arranged on the telescopic bellows, the second connecting pipeline is used for connecting with a laser isotope analyzer, and the fifth electromagnetic valve is arranged on the second connecting pipeline.

[0009] In an optional embodiment, one end of the telescopic bellows is provided with a first connecting plate, and the other end is provided with a second connecting plate; a plurality of first perforations are arranged on the first connecting plate, and a plurality of second perforations corresponding to the first perforations are arranged on the second connecting plate. A guide rod is arranged on the first perforation, and the guide rod extends into the second perforation; the first connecting plate or the second connecting plate is fixedly connected with the guide rod.

[0010] In an optional embodiment, a telescopic driving member is further included, one end of the telescopic driving member is connected with one end of the telescopic bellows, and the telescopic driving member drives the telescopic bellows to extend or retract.

[0011] In an optional embodiment, the second connecting plate is fixedly connected with the guide rod. The telescopic driving member includes a driving plate, the driving plate is connected with the first connecting plate, and the driving plate is used for driving the first connecting plate to move along the guide rod. In an optional embodiment, the driving plate is arranged on a side of the first connecting plate away from the second connecting plate, and a plurality of connecting rods are arranged on the driving plate. One end of the connecting rod is connected with the driving plate, and the other end is connected with the first connecting plate. In an optional embodiment, a guide hole corresponding to the first perforation is arranged on the driving plate, and the guide rod extends into the guide hole of the driving plate. In an optional embodiment, the telescopic driving member is an electric motor, which is screwed with the driving plate through a driving rod. The sample gas amount of the gas mixing interface device can enter into the telescopic bellows after accurate metering by the metering pipe, and the dilution gas amount can also enter into the telescopic bellows after accurate metering by the metering pipe, so that the mixing ratio of the two kinds of gases is accurate and stable in the case of changing sample gas amount, and the mixing ratio is consistent with the reference gas mixing ratio; the telescopic bellows can make the two kinds of gases in the telescopic bellows quickly and fully mixed and uniform, thereby improving the gas mixing efficiency; the mixed gas can be compressed into the laser isotope analyzer for testing by the contraction of the bellows, and the number of repeated detections of different samples can be accurately calculated, so that accurate testing is realized, and the sample testing rate and testing accuracy are effectively improved; the negative pressure pump can evacuate the whole mixing device, thereby effectively reducing the gas residue. The device can greatly improve the testing accuracy of the laser isotope analyzer, and is more important for testing trace samples and low-content samples. BRIEF DESCRIPTION OF DRAWINGS

[0012] In order to more clearly illustrate the technical solutions in the specific embodiments or prior art of the present application, the drawings needed in the description of the specific embodiments or prior art will be briefly introduced. Obviously, the drawings in the following description are some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0013] Figure 1 The structure schematic diagram of the gas mixing interface device provided by the embodiments of the present application is shown in the figure. Figure 2 The structure schematic diagram of the telescopic bellows of the gas mixing interface device is shown in the figure. Figure 1 The structure schematic diagram of the telescopic bellows of the gas mixing interface device is shown in the figure.

[0014] Figure: 100-meter pipe; 101-first connecting end; 102-second connecting end; 200-first electromagnetic valve; 300-high pressure sensor; 400-second electromagnetic valve; 500-first connecting pipeline; 600-first branch; 700-negative pressure pump; 800-third electromagnetic valve; 900-low pressure sensor; 110-fourth electromagnetic valve; 120-telescopic bellows; 130-fifth electromagnetic valve; 140-first connecting plate; 141-first perforation; 150-second connecting plate; 151-second perforation; 160-connecting rod; 170-driving plate; 171-guiding hole; 180-driving rod; 190-guiding rod. DETAILED DESCRIPTION

[0015] The terms “first,” “second,” “third,” etc., are used only for distinguishing descriptions and do not indicate a sequence number, nor should they be interpreted as indicating or implying relative importance.

[0016] Furthermore, terms such as "horizontal," "vertical," and "sag" do not imply that components must be absolutely horizontal or suspended, but rather that they can be slightly tilted. For example, "horizontal" simply means that its direction is more horizontal relative to "vertical," and does not mean that the structure must be completely horizontal, but can be slightly tilted.

[0017] In the description of this application, it should be noted that the terms "inner", "outer", "left", "right", "upper", "lower", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product of this application is in use. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0018] In the description of this application, unless otherwise expressly specified and limited, the terms “set up,” “install,” “connect,” and “link” shall be interpreted broadly, for example, as a fixed connection, a detachable connection, or an integral connection; as a mechanical connection or an electrical connection; as a direct connection or an indirect connection through an intermediate medium; or as a connection within two components.

[0019] The technical solution of this application will now be clearly and completely described with reference to the accompanying drawings.

[0020] Example Reference Figure 1 and Figure 2 The present invention provides a gas mixing interface device, including a metering tube 100 and a telescopic corrugated tube 120, wherein the metering tube 100 is connected to the telescopic corrugated tube 120 through a first connecting pipe 500. The metering tube 100 has a first connection end 101, a second connection end 102, a third connection end and a fourth connection end. The first connection end 101 is used to connect to the dilution gas system, the second connection end 102 is used to connect to the sample preparation device, the third connection end is equipped with a high-pressure sensor 300, and the fourth connection end is used to connect to the first connection pipeline 500. A first solenoid valve 200 is provided at the first connection end 101, and a second solenoid valve 400 is provided at the second connection end 102; a first branch 600 is provided on the first connection pipeline 500, one end of the first branch 600 is connected to the first connection pipeline 500, and the other end is connected to the negative pressure pump 700; a third solenoid valve 800 is provided on the first branch 600. A fourth solenoid valve 110 is provided on the first connecting pipe 500, and the fourth solenoid valve 110 is located upstream of the telescopic bellows 120; a fifth solenoid valve 130 is provided downstream of the telescopic bellows 120.

[0021] The sample gas from the gas mixing interface device can enter the telescopic bellows 120 through the metering tube 100, and the dilution gas can also enter the telescopic bellows 120 through the metering tube 100. The expansion and contraction of the telescopic bellows 120 ensures thorough mixing of the gases within, resulting in a uniform mixture and improved mixing efficiency. This also enables precise and repeatable testing of different samples, effectively increasing the sample utilization rate and accuracy of the laser isotope analyzer, which is particularly significant for testing trace or low-content samples. The negative pressure pump 700 can extract other gases from the first connecting pipe 500 and the metering tube 100, effectively reducing gas residue and enabling the laser isotope analyzer to test trace or low-content samples.

[0022] In an optional embodiment, a low-pressure sensor 900 is also provided on the first connecting pipe 500. The volume of the metering tube 100 is known, and the total volume of the metering tube 100 and the first connecting pipe 500 is known. When testing is required, the telescopic bellows 120 is in the extended state. The third solenoid valve 800 on the first branch 600 and the fourth solenoid valve 110 on the first connecting pipe 500 are opened, and the negative pressure pump 700 extracts the gas from the telescopic bellows 120 and the metering tube 100. After evacuation, all solenoid valves are closed.

[0023] Open the second solenoid valve 400 to allow the pure target gas generated in the sample preparation device to enter the metering tube 100, and then close the second solenoid valve 400. The low-pressure sensor 900 reads the pressure of the gas in the metering tube 100. According to the ideal gas law, the molar concentration of the target gas in the metering tube 100 can be calculated using Formula 1.

[0024] Formula 1n 目标气体量 = P 低压传感器 ×V 计量管 / R×T; n: quantity of gas (mol) P: Gas pressure (Pa); V: Volume (m³) 3 ); R: Ideal gas constant (L.atm / mol.K); T: Absolute temperature of the gas (K); Where P is the pressure, displayed by the high-pressure sensor 300 and the low-pressure sensor 900. R and T are constants, where R is 0.0821 L·atm / mol·K and T is the standard temperature of 273.15 K.

[0025] The volume of metering tube 100 is the volume between the fourth solenoid valve 110 and metering tube 100 and the actual volume of metering tube 100.

[0026] Open the fourth solenoid valve 110, and the target gas in the metering tube 100 enters the telescopic bellows 120.

[0027] Close the fourth solenoid valve 110 and open the third solenoid valve 800 to extract the gas from the metering tube 100; due to n 目标气体量 Given that the required mixing ratio, which is the mixing ratio of the target gas and the diluent gas in the reference gas, is known, the amount of diluent gas that needs to be supplied can be accurately calculated according to Formula 2.

[0028] Formula 2n 稀释气体量 =n 目标气体量 / Reference gas mixing ratio; The volume of metering tube 100 and the amount of dilution gas to be supplied are known. According to Formula 3, the pressure that the high-pressure sensor 300 should reach in metering tube 100 can be obtained.

[0029] Formula 3P 高压传感器 =(n 稀释气体量 ×R×T) / V 计量管 ; When the first solenoid valve 200 is opened, the dilution gas enters the metering tube 100. When the high-pressure sensor 300 reaches the threshold calculated by formula 4, the first solenoid valve 200 is automatically closed. Since the pressure in the metering tube 100 is very high at this time, while the pressure in the bellows is low, when the fourth solenoid valve 110 is opened, the dilution gas will quickly flush into the telescopic bellows 120. This achieves high-precision mixing of the sample gas and dilution gas, and the mixing ratio is consistent with the reference gas protection, thereby maximizing the accuracy of the test data from the downstream laser isotope analyzer.

[0030] When the fourth solenoid valve 110 is closed, the telescopic bellows 120 extends and retracts, allowing the target gas and diluent gas to mix rapidly and evenly within the bellows.

[0031] Calculation of the number of times a single sample can be repeatedly tested: As stated above, the gas quantity n in the expansion bellows 120 is... 波纹管气体量 ≈n 目标气体量 +n 稀释气体量The volume of the optical cell and the test pressure inside different models of laser isotope analyzers are fixed. According to the ideal gas law formula, the amount of gas required for the optical cell during the test can be determined. According to Formula 4, the number of times the mixed gas in the bellows can be repeatedly tested in the optical cell can be calculated, which is the number of times the sample can be repeatedly measured, R.

[0032] Formula 4 R=n 波纹管气体量 / n 光学池气体量 Based on this, the number of times different samples can be repeatedly tested can be accurately calculated. According to the determined number of repeated tests, the fifth solenoid valve 130 is opened in stages to allow the mixed gas in the telescopic bellows 120 to enter the optical cell of the laser isotope analyzer in equal portions for isotope testing and analysis.

[0033] In an optional embodiment, the telescopic bellows 120 is provided with a second connecting pipe for connecting to the optical cell of the laser isotope analyzer, and the fifth solenoid valve 130 is provided on the second connecting pipe.

[0034] In an optional embodiment, the telescopic bellows 120 is provided with a second connecting pipe for connecting to a laser isotope analyzer, and the fifth solenoid valve 130 is provided on the second connecting pipe.

[0035] Reference Figure 2 In an optional embodiment, one end of the telescopic corrugated pipe 120 is provided with a first connecting plate 140 and the other end is provided with a second connecting plate 150; and a plurality of first through holes 141 are provided on the first connecting plate 140, and a second through hole 151 corresponding to the first through hole 141 is provided on the second connecting plate 150. A guide rod 190 is provided through the first through hole 141, and the guide rod 190 extends into the second through hole 151; the first connecting plate 140 or the second connecting plate 150 is fixedly connected to the guide rod 190.

[0036] In an optional embodiment, a telescopic drive is further included, one end of which is connected to one end of the telescopic bellows 120, and the telescopic drive causes the telescopic bellows 120 to extend or retract.

[0037] In an optional embodiment, the second connecting plate 150 is fixedly connected to the guide rod 190; The telescopic drive includes a drive plate 170, which is connected to the first connecting plate 140. The drive plate 170 is used to move the first connecting plate 140 along the guide rod 190. In an optional embodiment, the drive plate 170 is disposed on the side of the first connecting plate 140 away from the second connecting plate 150, and a plurality of connecting rods 160 are disposed on the drive plate 170. One end of the connecting rod 160 is connected to the drive plate 170, and the other end is connected to the first connecting plate 140. In an optional embodiment, the drive plate 170 is provided with a guide hole 171 corresponding to the first through hole 141, and the guide rod 190 extends into the guide hole 171 of the drive plate 170. In an optional embodiment, the telescopic drive component is a motor, which is screwed to the drive plate 170 via a drive rod 180. In some embodiments, a first connecting plate 140 is provided at one end of the telescopic corrugated pipe 120, and a second connecting plate 150 is provided at the other end. The first connecting plate 140 is provided with a plurality of first through holes 141, and the second connecting plate 150 is provided with a plurality of second through holes 151. The first through holes 141 and the second through holes 151 are correspondingly provided. The guide rod 190 is simultaneously inserted into the first through holes 141 and the second through holes 151, and the second connecting plate 150 is fixedly connected to the guide rod 190.

[0038] The telescopic drive component is connected to the first connecting plate 140 of the telescopic bellows 120. The first connecting plate 140 moves along the guide rod 190, thereby enabling the telescopic bellows 120 to extend and retract, and thus adjusting the internal volume of the telescopic bellows 120.

[0039] Multiple connecting rods 160 are provided between the drive plate 170 and the first connecting plate 140. The drive plate 170 causes the first connecting plate 140 to move synchronously, thereby enabling more precise adjustment of the volume of the telescopic bellows 120.

[0040] The gas mixing interface device provided by this invention allows the sample gas volume to be precisely measured by the metering tube 100 before entering the telescopic bellows 120, and the dilution gas volume to also be precisely measured by the metering tube 100 before entering the telescopic bellows 120. This ensures that the mixing ratio of the two gases remains accurate and stable even when the sample gas volume changes, while maintaining consistency with the reference gas mixing ratio. The expansion and contraction of the telescopic bellows 120 allows for rapid and thorough mixing of the two gases within it, improving mixing efficiency. The contraction of the bellows maximizes the compression of the mixed gas into the laser isotope analyzer for testing, while also accurately calculating the number of repeated tests for different samples, achieving precise testing and effectively improving the testing rate and accuracy. The negative pressure pump 700 evacuates the entire mixing device, effectively reducing gas residue. This device significantly improves the testing accuracy of the laser isotope analyzer, and is particularly important for testing trace samples and samples with low concentrations.

[0041] This application effectively solves the technical problem that, due to the different properties of solid samples, the amount of target gas generated by the front-end solid sample preparation device varies greatly, and the mixing ratio of sample gas and dilution gas in existing technologies is inaccurate and unstable, and it is difficult to maintain a consistent mixing ratio with the reference gas. This application, through a metering tube 100 of known volume and a low-pressure sensor 900, can accurately measure the amount of target gas produced by each sample in the preparation device. Based on the reference gas mixing ratio, it accurately calculates the amount of dilution gas to be supplied, and then uses a high-pressure sensor 300 to precisely preload the required amount of dilution gas into the metering tube 100. This achieves high-precision and stable mixing of sample gas and dilution gas even when the sample gas is constantly changing, and ensures that the final mixed sample gas mixing ratio is close to the reference gas mixing ratio. This technical method will fundamentally improve the quality of isotope data produced by laser isotope analyzers.

[0042] The proposed solution not only effectively solves the problems of low gas measurement rate and the inability to perform repeated testing on each sample, but also clearly calculates the number of times different samples can be repeatedly tested. Existing technologies, regardless of the amount of target gas generated by a solid sample, can only test each sample once, and the remaining gas must be completely vented, preventing the laser isotope analyzer from effectively improving testing accuracy. The proposed solution, through the metering tube 100, low-pressure sensor 900, and high-pressure sensor 300, can accurately measure the amount of target gas and dilution gas generated by different solid samples. This allows for the accurate calculation of the number of times the mixed gas of each sample can be repeatedly tested. By setting the number of times the solenoid valve opens, the mixed gas is divided equally for multiple tests, which greatly improves the testing accuracy of laser isotope analysis and reduces abnormal data disturbances.

[0043] The solution presented in this application effectively solves the problem of low gas measurement rate in existing technologies. Existing technologies use metal cylinders or gas bags to mix the target gas and dilution gas, resulting in a significant portion of the gas remaining in the mixer and unable to enter the optical cell of the laser isotope analyzer for testing and analysis. The solution presented in this application uses a telescopic bellows 120 as the gas mixer. By compressing the telescopic bellows 120, the sample mixture can be delivered into the isotope analyzer to the maximum extent possible. This is of great significance for trace samples and low-content samples, effectively solving the problem of difficult testing of such samples.

[0044] The solution presented in this application effectively solves the problem of low mixing efficiency between the two gases, achieving rapid and thorough uniform mixing. Existing technologies address the issue of uniform mixing through secondary mixing and prolonged settling, resulting in long mixing times and low efficiency. The mixer in this application utilizes a flexible and retractable bellows 120. The expansion and contraction of the bellows 120 rapidly and uniformly mixes the two gases. This method also effectively reduces mixing unevenness caused by the dead volume of the container itself.

[0045] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A gas mixing interface device, characterized in that, It includes a metering tube (100) and a telescopic corrugated pipe (120), wherein the metering tube (100) is connected to the telescopic corrugated pipe (120) through a first connecting pipe (500); The metering tube (100) has a first connection end (101), a second connection end (102), a third connection end and a fourth connection end. The first connection end (101) is used to connect to the dilution gas system, the second connection end (102) is used to connect to the sample preparation device, the third connection end is equipped with a high-pressure sensor (300), and the fourth connection end is used to connect to the first connection pipeline (500). A first solenoid valve (200) is provided at the first connection end (101), and a second solenoid valve (400) is provided at the second connection end (102); a first branch (600) is provided on the first connection pipeline (500), one end of the first branch (600) is connected to the first connection pipeline (500), and the other end is connected to the negative pressure pump (700); a third solenoid valve (800) is provided on the first branch (600). A fourth solenoid valve (110) is provided on the first connecting pipe (500), and the fourth solenoid valve (110) is located upstream of the telescopic bellows (120); a fifth solenoid valve (130) is provided downstream of the telescopic bellows (120).

2. The gas mixing interface device according to claim 1, characterized in that, A low-pressure sensor (900) is also installed on the first connecting pipe (500).

3. The gas mixing interface device according to claim 2, characterized in that, The telescopic corrugated pipe (120) is provided with a second connecting pipe, which is used to connect to the laser isotope analyzer, and the fifth solenoid valve (130) is provided on the second connecting pipe.

4. The gas mixing interface device according to claim 3, characterized in that, The telescopic corrugated pipe (120) is provided with a first connecting plate (140) at one end and a second connecting plate (150) at the other end; and a plurality of first through holes (141) are provided on the first connecting plate (140), and a second through hole (151) corresponding to the first through hole (141) is provided on the second connecting plate (150). A guide rod (190) is provided through the first through hole (141), and the guide rod (190) extends into the second through hole (151); the first connecting plate (140) or the second connecting plate (150) is fixedly connected to the guide rod (190).

5. The gas mixing interface device according to claim 4, characterized in that, It also includes a telescopic drive component, one end of which is connected to one end of the telescopic bellows (120), and the telescopic drive component causes the telescopic bellows (120) to extend or retract.

6. The gas mixing interface device according to claim 5, characterized in that, The second connecting plate (150) is fixedly connected to the guide rod (190); The telescopic drive includes a drive plate (170) connected to the first connecting plate (140), and the drive plate (170) is used to move the first connecting plate (140) along the guide rod (190).

7. The gas mixing interface device according to claim 6, characterized in that, The drive plate (170) is disposed on the side of the first connecting plate (140) away from the second connecting plate (150), and a plurality of connecting rods (160) are provided on the drive plate (170). One end of the connecting rod (160) is connected to the drive plate (170), and the other end is connected to the first connecting plate (140).

8. The gas mixing interface device according to claim 7, characterized in that, The drive plate (170) is provided with a guide hole (171) corresponding to the first through hole (141), and the guide rod (190) extends into the guide hole (171) of the drive plate (170).

9. The gas mixing interface device according to claim 8, characterized in that, The telescopic drive component is a motor, which is screwed to the drive plate (170) via a drive rod (180).

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