A system for detecting nanoparticles in an ambient gas and a method of controlling the same

Abstract

The application relates to a detection system for nanoparticles in environmental gas and a control method thereof, which comprises a sampling assembly provided with a sampling pump and a first filter; a detection chamber connected with one gas outlet of the sampling assembly through a second filter and a first control valve in sequence; the detection chamber is used for detecting the nanoparticles in the environmental gas collected by the sampling assembly; a pressure regulating chamber is provided with an air flow channel and a second control valve at a position where an air inlet of the pressure regulating chamber is communicated with an air outlet of the detection chamber; and a vacuum exhaust device is arranged on the pressure regulating chamber. When the second control valve is opened, the detection chamber and the pressure regulating chamber are communicated, the pressure in the detection chamber is reduced, the internal energy of the gas molecules in the detection chamber is reduced, the nanoparticles have the condition of forming condensation nuclei, and the nanoparticles can be detected by the detection chamber. Since the pressure values of the detection chamber and the pressure regulating chamber are kept at normal pressure or negative pressure during the process of forming the condensation nuclei by the nanoparticles, the service life of the detection chamber is improved to a certain extent.

Description

Technical Field

[0001] This application relates to the field of online fire safety monitoring technology, and in particular to a detection system and control method for nanoparticles in ambient gases. Background Technology

[0002] In the field of online fire safety monitoring, ambient gases often contain a wealth of safety information. Utilizing this information can help detect potential safety hazards early, before a fire occurs. For example, in environments with concentrated circuits, such as power distribution rooms and battery storage boxes, overheating of lines can easily escalate into a serious fire if not addressed promptly, causing significant equipment damage and personal injury. In the initial stages of an accident, the surface temperature of the circuit gradually increases, and the coating layer releases a large number of nanoparticles with diameters ranging from 2nm to 10nm. When the surface temperature continues to rise to a certain threshold, the nanoparticles transform into carbon particles, which then dissolve and burn, accompanied by the generation of toxic gases such as smoke with diameters ranging from 400nm to 1200nm and carbon monoxide. If early warning of environmental safety can be issued during the nanoparticle generation stage, it can significantly buy maintenance personnel valuable time for rescue efforts.

[0003] In some related technologies, to achieve early warning and detection of fires at very early stages, active air sampling is employed. Those skilled in the art often use a sampling pump to sample ambient gas and then deliver the sampled gas to a cloud chamber for optical detection. Because nanoparticles are extremely small, current optical detection technologies cannot directly detect them. Therefore, the sampled gas needs to undergo certain pretreatment during delivery to the cloud chamber to enlarge the nanoparticle size to a level suitable for optical detection. However, the following problems exist:

[0004] During the detection process, the thermodynamic properties of gas molecules need to be fully utilized, which requires the gas to be compressed within the detection chamber. Since the detection chamber needs to withstand large pressure periodically, it has a certain impact on the sealing performance and structural reliability of the detection chamber, and seriously affects the lifespan of the detection chamber. Summary of the Invention

[0005] This application provides a detection system and control method for nanoparticles in ambient gas to solve the problem in related technologies where the detection chamber needs to withstand large pressure periodically, which affects the lifespan of the detection chamber.

[0006] In a first aspect, a detection system for nanoparticles in ambient gases is provided, comprising:

[0007] The sampling assembly is equipped with a sampling pump and has two air outlets and one air inlet, with a first filter at the air inlet.

[0008] The detection assembly has a detection chamber and a pressure regulating chamber;

[0009] The detection chamber is connected to one of the air outlets of the sampling assembly via a second filter and a first control valve connected in sequence; the detection chamber is used to detect nanoparticles in the ambient gas collected by the sampling assembly.

[0010] The pressure regulating chamber is connected to a vacuum exhaust device; at least one airflow channel is formed between the air inlet of the pressure regulating chamber and the air outlet of the detection chamber, which can be connected or blocked by a second control valve.

[0011] In some embodiments, the detection chamber and the pressure regulating chamber are spaced apart, and the detection chamber has a chamber outlet on one side, while the pressure regulating chamber has a chamber inlet on the side facing the detection chamber that corresponds to the chamber outlet.

[0012] The air outlet of the chamber and the air inlet of the chamber are connected by a connecting piece to form the airflow channel;

[0013] The second control valve is provided on the connecting component.

[0014] In some embodiments, the detection chamber has a chamber outlet on one side, and the pressure regulating chamber has a chamber inlet on the side facing the detection chamber; the side of the detection chamber with the chamber outlet abuts against the side of the pressure regulating chamber with the chamber inlet, and the two can move relative to each other.

[0015] The detection system also includes a drive structure, which is fixedly connected to the detection chamber or the pressure regulating chamber to drive the chamber outlet and the chamber inlet to connect or disconnect when the detection chamber and the pressure regulating chamber move relative to each other.

[0016] In some embodiments, the volume of the detection chamber is smaller than the volume of the pressure regulating chamber.

[0017] In some embodiments, the volume ratio of the detection chamber to the pressure regulating chamber is 1 / 6 to 1 / 2.

[0018] In some embodiments, the inner wall of the detection chamber is provided with an anti-reflective layer; the outer walls of the detection chamber and the pressure regulating chamber are provided with a heat insulation layer.

[0019] In some embodiments, both the detection chamber and the pressure regulating chamber are equipped with pressure sensors for detecting air pressure.

[0020] Secondly, a control method for a detection system of nanoparticles in ambient gases is provided, comprising the following steps:

[0021] S01: Open the first control valve and the second control valve to connect the airflow channel; at the same time, start the sampling pump and vacuum exhaust device for a first set time so that the detection chamber and the pressure regulating chamber are filled with sampling gas while maintaining normal pressure;

[0022] S02: Close the first control valve, the second control valve and the sampling pump, and then continue to run the vacuum exhaust device for the second set time to evacuate the pressure regulating chamber into a vacuum;

[0023] S03: Close the vacuum exhaust device and open the second control valve, while simultaneously detecting nanoparticles in the ambient gas collected by the sampling component.

[0024] In some embodiments, the first set time is 2s to 4s; the second set time is 0.5s to 2s.

[0025] In some embodiments, step S02 can be replaced by:

[0026] Close the first control valve, the second control valve, and the sampling pump, and then continue to operate the vacuum exhaust device until the pressure in the pressure regulating chamber reaches the first pressure value.

[0027] The beneficial effects of the technical solution provided in this application include:

[0028] This application provides a detection system and control method for nanoparticles in ambient gas. The process involves opening a first control valve and connecting a detection chamber and a pressure regulating chamber using a second control valve; simultaneously starting a sampling pump and a vacuum exhaust device for a first set time to fill the detection chamber and the pressure regulating chamber with sampling gas while maintaining normal pressure; closing the first control valve and the sampling pump, and then continuing to run the vacuum exhaust device until a second set time to evacuate the pressure regulating chamber to a vacuum; closing the vacuum exhaust device, and simultaneously opening the second control valve to detect nanoparticles in the ambient gas collected by the sampling component.

[0029] The detection principle is as follows: When the connecting piece is opened, the detection chamber and the pressure regulating chamber are connected. Since the pressure in the detection chamber is normal and the pressure in the pressure regulating chamber is negative, the pressure difference causes the pressure in the detection chamber to drop and does work on the pressure regulating chamber, reducing the internal energy of molecules. During this process, nanoparticles in the detection chamber form condensation nuclei, causing invisible particles with a diameter as small as 0.002 μm to be magnified into detectable water droplets with a diameter range of 10 μm-20 μm; these droplets can then be detected by the detection chamber.

[0030] This ensures that the pressure values ​​of the detection chamber and the pressure regulating chamber remain at normal or negative pressure during the formation of condensation nuclei by nanoparticles, which improves the sealing performance of the detection chamber and the pressure regulating chamber. This method also eliminates the need for frequent gas compression, thus extending the lifespan of the detection chamber to a certain extent. Attached Figure Description

[0031] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 A schematic diagram of the overall structure of the detection system for nanoparticles in ambient gas provided in an embodiment of this application;

[0033] Figure 2 A schematic diagram of the first structure of the connecting member in the first structure for connecting the detection chamber and the pressure regulating chamber provided in the embodiments of this application;

[0034] Figure 3 This is a schematic diagram of a second structure of a connecting element provided in an embodiment of this application;

[0035] Figure 4 This is a schematic diagram of a second structure in which the detection chamber and the pressure regulating chamber are connected, as provided in an embodiment of this application.

[0036] Figure 5 for Figure 4 A schematic diagram showing the shapes of the air outlet and air inlet;

[0037] Figure 6 This is a schematic diagram showing the status of each component of the system under N working cycles.

[0038] In the diagram: 1. Sampling assembly; 2. Detection chamber; 3. Pressure regulating chamber; 4. First filter; 5. Second filter; 6. First control valve; 9. Connecting component; 900. Connecting pipe; 901. Second control valve; 10. Vacuum pump; 11. Sampling pump; 12. Exhaust pump; 13. Pressure sensor. Implementation

[0039] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0040] This application provides a detection system and control method for nanoparticles in ambient gas to solve the problem in related technologies where the detection chamber needs to withstand large pressure periodically, which affects the lifespan of the detection chamber.

[0041] Please see Figure 1 A detection system for nanoparticles in ambient gases, comprising:

[0042] The sampling component 1 is equipped with a sampling pump 11 and has two air outlets and one air inlet. The air inlet is equipped with a first filter 4. The sampling component 1 can be regarded as a pipeline. The first filter 4 is used for coarse filtration of large-particle dust and other substances in the ambient gas.

[0043] The detection assembly has a detection chamber 2 and a pressure regulating chamber 3; the detection chamber 2 is connected to one of the air outlets of the sampling assembly 1 via a second filter 5 and a first control valve 6 connected in sequence; the second filter 5 is used to filter particles larger than 300nm in the detection branch.

[0044] The detection chamber 2 is used to detect nanoparticles in the ambient gas collected by component 1; the pressure regulating chamber 3 has at least one airflow channel between its inlet and the outlet of the detection chamber 2, which can be connected or blocked by a second control valve 901. That is, the connection between the pressure regulating chamber 3 and the detection chamber 2 is also provided with a second control valve 901 for controlling the opening or closing of the airflow channel; the pressure regulating chamber 3 is equipped with a vacuum exhaust device. The vacuum exhaust device includes a vacuum pump 10 and / or an exhaust pump 12.

[0045] With the above settings, the usage process is as follows:

[0046] The first control valve 6 is opened, and the detection chamber 2 and the pressure regulating chamber 3 are connected using the second control valve 901. Simultaneously, the sampling pump 11 and the vacuum exhaust device are started for a first set time to ensure that the detection chamber 2 and the pressure regulating chamber 3 are filled with sampling gas while maintaining normal pressure. That is, the sampling pump 11 draws external gas into the sampling assembly, with a portion exiting from its other outlet, and the remaining portion, after being filtered by the second filter 5, enters the detection chamber 2, and finally enters the pressure regulating chamber 3, before being discharged from the exhaust pump 12 or the vacuum pump 10. It should be noted that if the exhaust pump 12 does not exhaust gas, the gas inside the detection chamber 2 cannot be quickly filled at normal pressure. Therefore, the exhaust pump 12 needs to intermittently sample the gas in the detection chamber 2 and the pressure regulating chamber 3 to ensure that the gas is filled. The vacuum pump 10 and the exhaust pump 12 can be integrated together. Specifically, the first set time is 2s to 4s, preferably 3s.

[0047] The first control valve 6, the second control valve 901, and the sampling pump 11 are closed. Then, the vacuum exhaust device continues to run for the second set time to evacuate the pressure regulating chamber 3 into a vacuum. The vacuum exhaust device is then closed, and while the second control valve 901 is opened, nanoparticles in the ambient gas collected by component 1 are detected for particle detection. The second set time is 0.5s to 2s, preferably 1s.

[0048] The detection principle is as follows: When the second control valve 901 is opened, the detection chamber 2 and the pressure regulating chamber 3 are connected. Since the pressure in the detection chamber 2 is normal pressure and the pressure in the pressure regulating chamber 3 is negative pressure, the pressure difference causes the pressure in the detection chamber 2 to decrease and do work on the pressure regulating chamber 3, causing the gas to expand and its internal energy to decrease. During this process, nanoparticles in the detection chamber 2 form condensation nuclei, magnifying invisible particles with a diameter as small as 0.002 μm into detectable water droplets with a diameter range of 10 μm-20 μm; these droplets can then be detected by the detection chamber. This transforms nanoparticles, which were originally undetectable by optical sensors, into condensation nucleus particles that can be detected by optical sensors, enabling early warning of environmental fires.

[0049] This ensures that the pressure values ​​of detection chamber 2 and pressure regulating chamber 3 remain at normal or negative pressure during the formation of condensation nuclei by nanoparticles, thus guaranteeing the sealing performance of detection chamber 2 and pressure regulating chamber 3. This method also eliminates the need for frequent gas compression, thereby extending the lifespan of detection chamber 2 to a certain extent.

[0050] In some preferred embodiments, the detection chamber 2 and the pressure regulating chamber 3 are configured in the following two ways;

[0051] See Figures 2-3 The first type involves separate detection chamber 2 and pressure regulating chamber 3, connected by a pipe. Specifically, detection chamber 2 and pressure regulating chamber 3 are spaced apart, with a chamber outlet on one side of detection chamber 2 and a chamber inlet corresponding to the chamber outlet on the side of pressure regulating chamber 3 facing detection chamber 2. The chamber outlet and chamber inlet are connected by a connecting piece 9 to form an airflow channel. A second control valve 901 is installed on the connecting piece 9.

[0052] The connecting component 9 includes two pipe groups, which are respectively connected to the detection chamber 2 and the pressure regulating chamber 3; each pipe group includes multiple equally spaced connecting pipes 900; the two pipe groups are connected by a second control valve 901. In this design, several chamber outlets of the detection chamber 2 and several chamber inlets of the pressure regulating chamber 3 are controlled by a single valve, resulting in lower product cost. There is at least one connecting pipe 900. In the preferred embodiment, there are an even number of equally spaced connecting pipes 900, ranging from 2 to 8.

[0053] The connecting component 9 can also be configured to include two pipe groups, which are respectively connected to the detection chamber 2 and the pressure regulating chamber 3; each pipe group includes multiple equally spaced connecting pipes 900; the connecting pipes 900 in the two pipe groups correspond one-to-one, and the corresponding connecting pipes 900 are connected to each other by a second control valve 901. In this configuration, the air outlets of several chambers in the detection chamber 2 and the air inlets of several chambers in the pressure regulating chamber 3 are each controlled by their respective multiple valves; the pressure relief rate is faster, and the particle amplification effect is better.

[0054] See Figures 4-5 The second type integrates the detection chamber 2 and the pressure regulating chamber 3 into one unit, specifically:

[0055] The detection chamber 2 has a chamber outlet on one side, and the pressure regulating chamber 3 has a chamber inlet on the side facing the detection chamber 2. The side of the detection chamber 2 with the chamber outlet abuts against the side of the pressure regulating chamber 3 with the chamber inlet, and the two can move relative to each other. The detection system also includes a drive structure, which is fixedly connected to the detection chamber 2 or the pressure regulating chamber 3 to drive the detection chamber 2 and the pressure regulating chamber 3 to connect or disconnect the chamber outlet and the chamber inlet when they move relative to each other. The relative movement can be understood as the drive structure driving the detection chamber 2 or the pressure regulating chamber 3 to move arbitrarily in all directions, including up, down, left, right, front, and back, and there is a gap between the chamber outlet and the chamber inlet during the movement.

[0056] Specifically, during the movement, when the detection chamber 2 and the pressure regulating chamber 3 are connected, the chamber outlet and the chamber inlet partially overlap; at the end of the movement, the chamber outlet and the chamber inlet completely overlap. At the initial position of the movement, when the detection chamber 2 and the pressure regulating chamber 3 are disconnected, the chamber outlet and the chamber inlet do not overlap. That is, the driving structure causes the chamber outlet and the chamber inlet to overlap or mutually cover each other, thus connecting or blocking the detection chamber and the pressure regulating chamber. The cross-sections of the detection chamber and the pressure regulating chamber in this design are as follows: Figure 3 As shown, A is the chamber outlet and B is the chamber inlet.

[0057] For specific references Figure 4 and Figure 5 The sides of the detection chamber 2 and the pressure regulating chamber 3 that are closely connected are complementary grids. When the detection chamber 2 and the pressure regulating chamber 3 are in the first relative position, the chamber outlet and the chamber inlet do not coincide and are not connected. When they are in the second relative position, the chamber outlet and the chamber inlet coincide and are connected. Specifically, the cross-section of the chamber outlet and the chamber inlet can be rectangular, circular, square or other shapes.

[0058] In this design, the entire particle amplification structure is based on the principle of adjusting the pressure in the pressure regulating chamber 3 to create negative pressure inside the detection chamber 2. When the air outlet and air inlet of the chamber overlap, the contact between the sides of the pressure regulating chamber 3 and the detection chamber will be tighter due to the negative pressure.

[0059] Furthermore, the volume of detection chamber 2 is smaller than the volume of pressure regulating chamber 3. Specifically, the ratio of the volume of detection chamber 2 to the volume of pressure regulating chamber 3 is... This ensures that when the gas in the detection chamber 2 diffuses into the pressure regulating chamber 3 at the instant the detection chamber 2 and the pressure regulating chamber 3 are connected, the pressure in the pressure regulating chamber 3 is not significantly affected, allowing the nanoparticles in the ambient gas to fully form condensation nuclei.

[0060] In some preferred embodiments, the inner wall of the detection chamber 2 is provided with an anti-reflection layer; the outer walls of the detection chamber 2 and the pressure regulating chamber 3 are provided with a heat insulation layer; the anti-reflection layer is made of pure black plastic material to prevent the detection light from reflecting between the chamber walls and affecting the detection results. The heat insulation layer uses a thermal insulation material with a low thermal conductivity, which is less than or equal to 0.12 W / (mK), such as mineral wool, foamed ceramic insulation board, etc.

[0061] In some preferred embodiments, the system also includes a buzzer for issuing an alarm based on the concentration of nanoparticles.

[0062] Both the detection chamber 2 and the pressure regulating chamber 3 are equipped with pressure sensors 13 for detecting air pressure. By detecting the pressure values ​​in the detection chamber 2 and the pressure regulating chamber 3, important index parameters are provided during the detection process. The specific operation steps are described in the specific embodiments below.

[0063] This application also proposes a control method for a detection system of nanoparticles in ambient gases, comprising the following steps:

[0064] S01: Open the first control valve 6 and the second control valve 901 to connect the airflow channel; at the same time, start the sampling pump 11 and the vacuum exhaust device for the first set time so that the detection chamber 2 and the pressure regulating chamber 3 are filled with sampling gas while maintaining normal pressure.

[0065] S02: Close the first control valve 6, the second control valve 901 and the sampling pump 11, and then continue to run the vacuum exhaust device for the second set time to evacuate the pressure regulating chamber 3 into a vacuum.

[0066] S03: Turn off the vacuum exhaust device and open the second control valve 901, while simultaneously detecting nanoparticles in the ambient gas collected by the sampling component.

[0067] Through the above steps, nanoparticles that are originally undetectable by optical sensors can be transformed into condensation nuclei that can be detected by optical sensors, enabling early warning of environmental fires.

[0068] Furthermore, step S02 can be replaced by: closing the first control valve 6, the second control valve 901, and the sampling pump 11, and then continuing to operate the vacuum exhaust device until the pressure in the pressure regulating chamber 3 reaches the first pressure value, which can be referred to in the specific embodiments below. The purpose of starting the second set time is also to achieve the first pressure value. Specifically, the first pressure value is -70Kpa to -50Kpa.

[0069] This application also provides a specific implementation method:

[0070] ① Open the first control valve 6 and the second control valve 901 to connect the detection chamber 2 and the pressure regulating chamber 3 using the connecting piece 9; at the same time, start the sampling pump 11 and the exhaust pump 12 for t1 seconds to fill the detection chamber and the pressure regulating chamber with sampling gas while maintaining normal pressure; in the best embodiment, t1=3s.

[0071] ② Close the first control valve 6, the second control valve 901, the sampling pump 11 and the exhaust pump 12, and then turn on the vacuum pump 10 for t2 seconds to evacuate the pressure regulating chamber to a vacuum. That is, turn on the vacuum pump to adjust the pressure value in the pressure regulating chamber to -70kPa~-50kPa to provide conditions for the gas expansion in the detection chamber; in the best embodiment, t2=1s.

[0072] ③ Turn off vacuum pump 10 and open second control valve 901. Simultaneously with opening second control valve 901, detect nanoparticles in the ambient gas collected by the sampling component. Repeat this intermittently N times in sequence.

[0073]

[0074] Under N work cycles, the status of each component of the system is as follows: Figure 6 As shown, p1 is at normal pressure, and p2 is at negative pressure; when the vacuum pump 10 reaches the pressure in the pressure regulating chamber 3 to -50 kPa, it stops pumping; the exhaust flow rate of the exhaust pump 12 and the vacuum pump 10 is 4 L / min; the volume ratio of the detection chamber 2 and the pressure regulating chamber 3 is 1:6; the volume of the detection chamber is approximately 0.0009 m³, and the volume of the pressure regulating chamber is approximately 0.006 m³; t1=3s; t2=1s; T=8s; these time interval parameters are calculated based on the volumes of the detection chamber and the pressure regulating chamber, the exhaust flow rate, and the actual requirements.

[0075] In the description of this application, it should be noted that the terms "upper," "lower," etc., indicating the orientation or positional relationship are based on the orientation or positional relationship shown in the accompanying drawings, and 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, and therefore should not be construed as a limitation of this application. Unless otherwise expressly specified and limited, the terms "installed," "connected," and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication between two elements. For those skilled in the art, the specific meaning of the above terms in this application can be understood according to the specific circumstances.

[0076] It should be noted that in this application, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0077] The above description is merely a specific embodiment of this application, enabling those skilled in the art to understand or implement this application. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features claimed herein.

Claims

1. A control method for a detection system of nanoparticles in ambient gas, characterized in that: The detection system for nanoparticles in the ambient gas includes: A sampling assembly (1) is provided with a sampling pump (11) and has two air outlets and one air inlet, the air inlet being provided with a first filter (4); a detection assembly is provided with a detection chamber (2) and a pressure regulating chamber (3); wherein the detection chamber (2) is connected to one of the air outlets of the sampling assembly (1) through a second filter (5) and a first control valve (6) connected in sequence; the detection chamber (2) is used to detect nanoparticles in the ambient gas collected by the sampling assembly (1); the pressure regulating chamber (3) is connected to a vacuum exhaust device; at least one airflow channel is formed between the air inlet of the pressure regulating chamber (3) and the air outlet of the detection chamber (2) that can be connected or blocked by a second control valve (901); The control method for the detection system of nanoparticles in the ambient gas includes: S01: Open the first control valve (6) and the second control valve (901) to connect the airflow channel; at the same time, start the sampling pump (11) and the vacuum exhaust device for a first set time so that the detection chamber (2) and the pressure regulating chamber (3) are filled with sampling gas while maintaining normal pressure; S02: Close the first control valve (6), the second control valve (901) and the sampling pump (11), and then continue to run the vacuum exhaust device for the second set time to evacuate the pressure regulating chamber (3) into a vacuum; S03: Close the vacuum exhaust device and open the second control valve (901), and at the same time detect the nanoparticles in the ambient gas collected by the sampling component (1).

2. The control method for the detection system of nanoparticles in ambient gas as described in claim 1, characterized in that: The detection chamber (2) and the pressure regulating chamber (3) are arranged at intervals, and the detection chamber (2) has a chamber outlet on one side, and the pressure regulating chamber (3) has a chamber inlet on the side facing the detection chamber (2) that corresponds to the chamber outlet. The chamber outlet and the chamber inlet are connected by a connector (9) to form the airflow channel; The second control valve (901) is provided on the connecting member (9).

3. The control method for the detection system of nanoparticles in ambient gas as described in claim 1, characterized in that: The detection chamber (2) has a chamber outlet on one side, and the pressure regulating chamber (3) has a chamber inlet on the side facing the detection chamber (2); the side of the detection chamber (2) with the chamber outlet abuts against the side of the pressure regulating chamber (3) with the chamber inlet, and the two can move relative to each other. The detection system also includes a drive structure, which is fixedly connected to the detection chamber (2) or the pressure regulating chamber (3) to drive the detection chamber (2) and the pressure regulating chamber (3) to connect or disconnect the chamber outlet and the chamber inlet when they move relative to each other.

4. The control method for the detection system of nanoparticles in ambient gas as described in any one of claims 1-3, characterized in that: The volume of the detection chamber (2) is smaller than that of the pressure regulating chamber (3).

5. The control method for the detection system of nanoparticles in ambient gas as described in claim 4, characterized in that: The volume ratio of the detection chamber (2) to the pressure regulating chamber (3) is 1 / 6 to 1 / 2.

6. The control method for the detection system of nanoparticles in ambient gas as described in claim 1, characterized in that: The inner wall of the detection chamber (2) is provided with an anti-reflection layer; the outer walls of the detection chamber (2) and the pressure regulating chamber (3) are provided with a heat insulation layer.

7. The control method for the detection system of nanoparticles in ambient gas as described in claim 1, characterized in that: Both the detection chamber (2) and the pressure regulating chamber (3) are equipped with pressure sensors (13) for detecting air pressure.

8. The control method for the detection system of nanoparticles in ambient gas according to claim 1, characterized in that, The first set time is 2s to 4s; The second set time is 0.5s to 2s.

9. The control method for the detection system of nanoparticles in ambient gas as described in claim 1, characterized in that, Step S02 can be replaced by: Close the first control valve (6), the second control valve (901) and the sampling pump (11), and then continue to run the vacuum exhaust device until the pressure in the pressure regulating chamber (3) reaches the first pressure value.

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