Injection type gas sampling device applied to ion mobility spectrometry

Abstract

According to the injection type gas sampling device applied to the ion mobility spectrometry, a gas sample can be collected on line, then positive pressure sample introduction is conducted, and the influence of environment pressure and the pump state on a migration tube working in the positive pressure state is reduced. According to the device, by adjusting the rotating speed of the motor and the sampling and sampling frequency, the operation of adding, mixing, diluting or reacting samples can be realized in the working modes of sampling for multiple times and sampling for one time, sampling for one time and sampling for multiple times or sampling for multiple times and sampling for multiple times and the like, and more new ideas are provided for the application research of the ion mobility spectrometry. The device can effectively reduce adsorption and residue of samples through a heating system, and is suitable for sampling and sample introduction occasions of various gases such as environmental gases and food safety. The device performs gas sampling and sample introduction under the positive pressure working condition of the migration tube, and has the characteristics of simplicity in operation, few residues, high sampling efficiency, multiple sampling and sample introduction modes and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of gas sampling, and in particular to an injection-type gas sampling device applied to ion mobility spectrometry. Background Art

[0002] Ion Mobility Spectrometer (IMS) is an analytical technique that works under atmospheric pressure. It is a technique that uses the different mobility of gaseous ions to qualitatively and quantitatively characterize different chemical substances in order to analyze and measure various substances. It has fast analysis speed, high sensitivity, low analysis cost, and convenient operation. It is suitable for trace detection of some volatile substances. The application of ion mobility spectrometry in explosives and other fields is relatively mature. With the development of high-performance ion mobility spectrometry, the application scope of ion mobility spectrometry has gradually expanded to fields such as environmental monitoring.

[0003] When ion mobility spectrometry is used for environmental monitoring, the sampling method often restricts the detection efficiency and sensitivity. Generally, when used for environmental monitoring, ion mobility spectrometry uses negative pressure sampling. Since the migration tube always works in a negative pressure state, higher requirements are placed on the sealing of the migration tube. If the sampling is continuous, the migration tube is not cleaned at intervals, resulting in sample residue and migration tube contamination; if the gas path is switched by a valve to achieve intermittent sampling, the gas pressure in the migration tube fluctuates when the valve is switched, affecting the signal stability.

[0004] A patent has been published, a handheld factory air sampling device (CN201922099109.6), which uses the injection principle to collect air at a higher position. Workers do not have to be at a higher position to sample and test the air, but the device only realizes sampling without the injection process. A patent has been published, a closed sampling device (CN202916136U), including a closed sampler and a sampling syringe, which can effectively prevent medium leakage, has a long service life, is not easy to break, and has good safety, but the patent is for manual sampling.

[0005] In order to realize the collection and injection of gas samples by the migration tube working under positive pressure, an injection type gas sampling device is designed, which can realize efficient sampling and injection without changing the working conditions of the migration tube. Summary of the invention

[0006] According to the technical problems mentioned in the above background technology, an injection type gas sampling device applied to ion mobility spectrometry is provided. The present invention solves the problem of how to sample and inject gas samples when the ion migration tube works under positive pressure, and realizes low loss, high efficiency sampling and injection and multiple sampling and injection methods. The technical means adopted by the present invention are as follows:

[0007] An injection type gas sampling device for ion mobility spectrometry, comprising: a motor, a bracket, a cam, a connecting rod, a push rod, an injection cylinder, a heating sleeve, a piston, a three-way valve, a one-way valve I, a one-way valve II and an ion migration tube;

[0008] The motor is arranged at the lower end of the bracket; the motor is provided with the cam; the cam is connected to the connecting rod; the syringe is arranged on the right outer side of the bracket; a piston is arranged in the syringe; the piston is connected to the push rod, and the push rod is further connected to the connecting rod; the outlet at one end of the syringe is connected to any one of the three-way ports; the other two ports of the three-way are respectively connected to the one-way valve I and the one-way valve II to realize the switching of the gas; the one-way valve II is connected to the ion migration tube; the heating sleeve is provided on the outer wrapping of the syringe to realize the constant temperature of the syringe;

[0009] The rotation of the motor drives the cam to rotate, and the cam drives the connecting rod and the push rod to move, thereby realizing the reciprocating motion of the piston in the injection cylinder;

[0010] When the piston is evacuating air, the one-way valve I opens, the one-way valve II closes, and the gas enters the syringe through the one-way valve I to achieve sampling; when the piston is pushed out, the one-way valve II opens, the one-way valve I closes, and the gas is pushed out of the syringe through the three-way valve and the one-way valve II in turn to achieve injection.

[0011] Furthermore, the bracket is an L-shaped bracket.

[0012] Furthermore, the one-way valve I and the one-way valve II conduct opposite air.

[0013] Furthermore, the one-way valve I is connected to the injection port; a filter element is provided at the injection port to realize gas filtering and injection; the one-way valve II is connected to the migration tube carrier gas to realize the injection of the sample into the migration tube carrier gas.

[0014] Furthermore, the ion transfer tube has two gas inlets and one gas outlet, namely, a floating gas inlet, a carrier gas inlet and a gas outlet.

[0015] Furthermore, the one-way valve II injects gas into the ion transfer tube or injects gas into the ion transfer tube together with the carrier gas.

[0016] Furthermore, the ion transfer tube can realize gas sampling and injection analysis when in a positive pressure working state.

[0017] Compared with the prior art, the present invention has the following advantages:

[0018] The present invention proposes an injection type gas sampling device applied to ion mobility spectrometry, which can collect gas samples online and then inject them under positive pressure. The migration tube working in a positive pressure state is less affected by the environmental pressure and the pump state. The device can adjust the sampling injection frequency by adjusting the speed of the motor, and can also realize multiple sampling and one injection, one sampling and multiple injections, or multiple sampling and multiple injections, and realize operations such as sample addition, mixing, dilution or reaction, providing more new ideas for the application research of ion mobility spectrometry.

[0019] The device can effectively reduce the adsorption and residue of samples through the heating system, and is suitable for various gas sampling and injection occasions such as environmental gas and food safety. The device performs gas sampling and injection under the positive pressure working condition of the migration tube, and has the characteristics of simple operation, less residue, high sampling efficiency, and multiple sampling and injection methods. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0021] Figure 1 The present invention is a schematic structural diagram of an injection-type gas sampling device applied to ion mobility spectrometry.

[0022] In the figure, 1 is a motor; 2 is a bracket; 3 is a cam; 4 is a connecting rod; 5 is a push rod; 6 is a syringe; 7 is a heating jacket; 8 is a piston; 9 is a three-way valve; 10 is a one-way valve I; 11 is an injection port; 12 is a filter element; 13 is a one-way valve II; 14 is an ion migration tube; 15 is a carrier gas; 16 is a floating gas; and 17 is an outlet. DETAILED DESCRIPTION

[0023] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first", "second", etc. in the specification and claims of the present invention and the above-mentioned drawings are used to distinguish similar objects, and are not necessarily used to describe a specific order or sequence. It should be understood that the data used in this way can be interchanged where appropriate, so that the embodiments of the present invention described herein can be implemented in an order other than those illustrated or described herein. In addition, the terms "including" and "having" and any variations thereof are intended to cover non-exclusive inclusions, for example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0025] like Figure 1 As shown, the present invention provides an injection type gas sampling device applied to ion mobility spectrometry, comprising:

[0026] Motor 1, bracket 2, cam 3, connecting rod 4, push rod 5, syringe 6, heating sleeve 7, piston 8, three-way 9, one-way valve I10, one-way valve II13 and ion migration tube 14;

[0027] The motor 1 is arranged at the lower end of the bracket 2; the cam 3 is arranged on the motor 1; the cam 3 is connected to the connecting rod 4; the syringe 6 is arranged on the right outer side of the bracket 2; a piston 8 is arranged in the syringe 6; the piston 8 is connected to the push rod 5, and the push rod 5 is further connected to the connecting rod 4; the outlet at one end of the syringe 6 is connected to any one of the ports of the three-way 9; the other two ports of the three-way 9 are respectively connected to the one-way valve I10 and the one-way valve II13 to realize the switching of gases; the one-way valve II13 is connected to the ion migration tube 14; the heating sleeve 7 is arranged outside the syringe 6 to realize the constant temperature of the syringe 6;

[0028] The motor 1 rotates to drive the cam 3 to rotate, and the cam 3 drives the connecting rod 4 and the push rod 5 to move, thereby realizing the reciprocating motion of the piston 8 in the injection cylinder 6;

[0029] When the piston 8 is evacuated, the one-way valve I10 is opened, the one-way valve II13 is closed, and the gas enters the syringe 6 through the one-way valve I10 to achieve sampling; when the piston 8 is pushed out, the one-way valve II13 is opened, the one-way valve I10 is closed, and the gas is pushed out of the syringe 6 through the three-way valve 9 and the one-way valve II13 in turn to achieve sampling.

[0030] As a preferred embodiment, the bracket 2 is an L-shaped bracket. The one-way valve I10 and the one-way valve II13 conduct opposite air.

[0031] Preferably, the one-way valve I10 is connected to the injection port 11 ; a filter element 12 is provided at the injection port 11 to realize gas filtering and injection; the one-way valve II13 is connected to the migration tube carrier gas 15 to realize sample injection into the migration tube carrier gas 15 .

[0032] Preferably, the ion transfer tube 14 has two gas inlets and one gas outlet, namely, the floating gas 16 , the carrier gas 15 and the gas outlet 17 .

[0033] In this embodiment, the one-way valve II13 injects gas into the ion transfer tube 14 or injects gas into the ion transfer tube 14 together with the carrier gas 15 .

[0034] Preferably, the ion transfer tube 14 realizes gas sampling and analysis when working in a positive pressure state.

[0035] In the present application, the filter element 12 is selected according to the actual situation. And the motor 1 can be a DC motor or a stepper motor. When the motor 1 is a stepper motor, the piston 8 can be controlled to use one injection for multiple samplings to complete the mixed injection of different samples. It can also achieve one sampling for multiple injections, thereby reducing the number of sampling times, or multiple sampling and multiple injections and other sampling and injection methods. If the motor 1 is a DC motor, the motor speed can be controlled to adjust the sampling and injection frequency to achieve intermittent continuous sampling and injection, thereby achieving quasi-continuous monitoring and analysis.

[0036] The serial numbers of the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.

[0037] In the above embodiments of the present invention, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0038] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. Among them, the device embodiments described above are only schematic. For example, the division of the units can be a logical function division. There may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of units or modules, which can be electrical or other forms.

[0039] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple units. Some or all of the units may be selected according to actual needs to achieve the purpose of the present embodiment.

[0040] In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0041] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, and the computer software product is stored in a storage medium, including a number of instructions for a computer device (which can be a personal computer, a server or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present invention. The aforementioned storage medium includes: U disk, read-only memory (ROM, Read Only Memory), random access memory (RAM, Random Access Memory), mobile hard disk, magnetic disk or optical disk and other media that can store program codes.

[0042] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements 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. An injection type gas sampling device for ion mobility spectrometry, characterized in that: include: A motor (1), a bracket (2), a cam (3), a connecting rod (4), a push rod (5), a syringe (6), a heating sleeve (7), a piston (8), a three-way valve (9), a one-way valve I (10), a one-way valve II (13) and an ion migration tube (14); The motor (1) is arranged at the lower end of the bracket (2); the cam (3) is arranged on the motor (1); the cam (3) is connected to the connecting rod (4); the injection barrel (6) is arranged on the right outer side of the bracket (2); a piston (8) is arranged in the injection barrel (6); the piston (8) is connected to the push rod (5), and the push rod (5) is further connected to the connecting rod (4); an outlet at one end of the injection barrel (6) is connected to any one of the ports of the three-way valve (9); the other two ports of the three-way valve (9) are respectively connected to a one-way valve I (10) and a one-way valve II (13) to achieve gas switching; the one-way valve II (13) is connected to the ion migration tube (14); the injection barrel (6) is wrapped with the heating sleeve (7) to achieve constant temperature of the injection barrel (6); The motor (1) rotates to drive the cam (3) to rotate, and the cam (3) drives the connecting rod (4) and the push rod (5) to move, thereby realizing the reciprocating motion of the piston (8) in the injection cylinder (6); When the piston (8) is evacuated, the one-way valve I (10) is opened, the one-way valve II (13) is closed, and the gas enters the syringe (6) through the one-way valve I (10), thereby achieving sampling; when the piston (8) is pushed out, the one-way valve II (13) is opened, the one-way valve I (10) is closed, and the gas is pushed out of the syringe (6) through the three-way valve (9) and the one-way valve II (13) in sequence, thereby achieving sampling.

2. The injection type gas sampling device for ion mobility spectrometry according to claim 1, characterized in that: The bracket (2) is an L-shaped bracket.

3. The injection type gas sampling device for ion mobility spectrometry according to claim 1, characterized in that: The one-way valve I (10) and the one-way valve II (13) conduct air in opposite directions.

4. The injection type gas sampling device for ion mobility spectrometry according to claim 1 or 3, characterized in that: The one-way valve I (10) is connected to the sample inlet (11); a filter element (12) is provided at the sample inlet (11) to realize gas filtering and sample injection; The one-way valve II (13) is connected to the migration tube carrier gas (15) to enable the sample to be injected into the migration tube carrier gas (15).

5. The injection type gas sampling device for ion mobility spectrometry according to claim 1, characterized in that: The ion migration tube (14) has two gas inlets and one gas outlet, namely, the floating gas (16), the carrier gas (15) and the gas outlet (17).

6. The injection type gas sampling device for ion mobility spectrometry according to claim 1, characterized in that: The one-way valve II (13) injects gas into the ion transfer tube (14) or injects gas into the ion transfer tube (14) together with the carrier gas (15).

7. An injection type gas sampling device for ion mobility spectrometry according to claim 1, 5 or 6, characterized in that: The ion migration tube (14) realizes gas sampling and injection analysis when in a positive pressure working state.

Images