A gas detection device convenient for automatic calibration

Abstract

The present application discloses a gas detection device that is easy to automatically calibrate, comprising a detection pipeline having a sampling port and an exhaust port; an air pump connected to the detection pipeline; a detection box having a detection chamber connected to the detection pipeline; an electrochemical sensor fixedly installed in the detection box; and a zero gas generator connected to the detection pipeline. The detection pipeline includes a main pipeline, a first branch pipeline, and a second branch pipeline, wherein a first solenoid valve is installed on the first branch pipeline and a second solenoid valve is installed on the second branch pipeline. The first branch pipeline and the second branch pipeline are both connected to the main pipeline, the sampling port is located at the air inlet end of the first branch pipeline, and the zero gas generator is connected to the second branch pipeline. The gas detection device includes an operating state and a calibration state. In the operating state, the first solenoid valve is open and the second solenoid valve is closed. In the calibration state, the first solenoid valve is closed and the second solenoid valve is open. The present application converts air into zero gas for calibration through a zero gas generator, which is relatively convenient.

Description

Technical Field

[0001] The present application relates to the technical field of gas detection, and in particular to a gas detection device that is easy to automatically calibrate. Background Art

[0002] Gas sensors, due to their low price, small size, ease of integration, and deployment, are becoming a new air pollutant monitoring technology, distinct from traditional monitoring methods. Environmental monitoring methods based on gas sensors are also being increasingly applied in diverse scenarios, such as ambient atmospheric monitoring, grid-based monitoring, and industrial monitoring. Commonly used gas sensors are categorized by their operating principles as electrochemical sensors, metal oxide sensors, photoionization sensors, and non-dispersive infrared sensors.

[0003] During the use of electrochemical sensor-based gas detection devices, the main factor affecting their lifespan is the electrolyte, which typically depletes after about two years and no longer functions properly. Furthermore, zero drift can occur after a few months of use, affecting subsequent measurement accuracy and requiring recalibration of the electrochemical sensor.

[0004] Traditional gas detection device manufacturers have traditionally used standard gas calibration methods to calibrate gas detection sensors. For highly volatile gases like formaldehyde and benzene, or nitrogen, standard gases are difficult to obtain and expensive, requiring electrochemical sensors to be sent back to the manufacturer for calibration and repair, making calibration inconvenient. Summary of the Invention

[0005] In order to improve the problem that gas detection devices in the prior art are difficult to calibrate,

[0006] The present application provides a gas detection device that is easy to automatically calibrate, using the following scheme:

[0007] A gas detection device that is convenient for automatic calibration, comprising:

[0008] A detection pipeline, wherein the detection pipeline has a sampling port connected to the ambient gas to be measured and an exhaust port for exhausting gas;

[0009] an air pump, connected to the detection pipeline, and used to drive the air flow in the detection pipeline to flow toward the exhaust port;

[0010] The detection box has a hollow detection chamber inside, and the detection chamber is connected to the detection pipeline;

[0011] an electrochemical sensor, the electrochemical sensor being fixedly mounted in the detection box and configured to perform contact detection on the gas in the detection chamber;

[0012] A zero gas generator is connected to the detection pipeline and is used to filter the outside air and convert it into zero gas;

[0013] The detection pipeline includes a main pipeline, a first branch and a second branch. A first solenoid valve is installed on the first branch, and a second solenoid valve is installed on the second branch. The air outlet ends of the first branch and the second pipeline are both connected to the main pipeline, the sampling port is located at the air inlet end of the first branch, and the zero gas generator is connected to the air inlet end of the second branch. The gas detection device includes an operating state for detecting the air flow to be measured and a calibration state for calibrating the electrochemical sensor. In the operating state, the first solenoid valve is opened and the second solenoid valve is closed, and the air flow to be measured enters the detection chamber for detection; in the calibration state, the first solenoid valve is closed and the second solenoid valve is opened, and the zero gas generator supplies zero gas to the detection chamber to calibrate the electrochemical sensor.

[0014] By adopting the above scheme, the air in the external environment can be filtered and converted into zero gas through the zero gas generator, so that zero gas can be easily supplied to the detection box for calibration, which is relatively convenient. On the one hand, in the process of pumping and extracting environmental gas for detection, long-term detection is usually not required; however, in the actual detection process, a large amount of environmental gas will inevitably remain in the pipeline and the detection box, causing the electrolyte in the electrochemical sensor to continue to react with the environmental gas, resulting in unnecessary consumption of the electrolyte, which reduces the service life of the electrochemical sensor; and the gas residue produced by the reaction will affect the accuracy of the next detection. In the technical solution of the present application, by introducing standard gas zero gas into the detection pipeline, the environmental gas in the pipeline and the detection box can be discharged in time, effectively reducing the loss of electrolyte in the electrochemical sensor and ensuring the life of the gas detection device. On the other hand, due to the problem of electrolyte consumption of electrochemical sensors, electrochemical sensors will usually have zero-point drift problems after a few months of use, affecting the accuracy of subsequent detection; the existing treatment solution is usually to perform zero-point calibration through standard gas, but standard gas is difficult to obtain and the cost is high, and it is usually necessary to return to the factory for zero-point calibration, which is relatively inconvenient. In the technical solution of the present application, by providing a zero gas generator, the ambient air can be effectively converted into zero gas, and the operation of the zero gas generator is automatically controlled by a solenoid valve. Under actual working conditions, the zero gas generator is automatically controlled to generate zero gas every few months to calibrate the electrochemical sensor in the detection box, which significantly improves the convenience of calibration and effectively ensures the long-term detection accuracy and stability of the gas detection device.

[0015] Optionally, the zero air generator includes a filter pipe and activated carbon filled in the filter pipe, the filter pipe has an air inlet and an air outlet, the air inlet is connected to the outside air, and the air outlet is connected to the second branch.

[0016] By adopting the above-mentioned solution, activated carbon is filled in the filter pipe, and the ambient gas in the filter pipe is filtered by the activated carbon, thereby realizing the preparation and supply of zero gas simply and effectively. In the traditional technical solution, it is usually necessary to send it back to the factory, and use the prepared nitrogen and gases such as formaldehyde and benzene as zero gas for calibration. The preparation cost of zero gas is high and the preparation process is complicated. The technical solution of the present application filters the ambient air by activated carbon, thereby simply and effectively removing pollutants in the ambient air to form zero gas; the filtering method of activated carbon significantly reduces the cost of zero gas preparation, thereby reducing the calibration cost of the gas detection device. In addition, in the traditional calibration process, a zero gas bottle of fixed capacity is usually used, and the bottle is filled with gas to supply zero gas. After the zero gas in the bottle is consumed, calibration can no longer be performed. If the volume of the bottle is increased, it will lead to excessive space occupation. The present application can achieve long-term sustainable zero gas production by combining the filter pipe with the filling of activated carbon, thereby improving the sustainable use performance of the gas detection device.

[0017] Optionally, the filter pipe is bent multiple times to form multiple bending parts.

[0018] By adopting the above scheme, the filter pipe is bent multiple times to form multiple bending parts. The provision of multiple bending parts can cause the ambient gas to be rotated and decelerated multiple times in the filter pipe, fully improving the contact time between the ambient air and the activated carbon, thereby fully improving the filtering effect of the activated carbon on the ambient air and ensuring the cleanliness of the generated zero gas.

[0019] Optionally, the zero air generating device is provided with an opening and closing member, which is installed at the air inlet of the filter pipe, and the opening and closing member works to open or close the air inlet of the filter pipe.

[0020] By adopting the above solution, an opening and closing part is provided at the air inlet of the filter pipe, and the opening and closing part can control the opening or closing of the air inlet of the filter pipe. In some other working conditions, since the air inlet of the filter pipe is not closed, the activated carbon in the filter pipe is always connected to the ambient air, resulting in a reduced service life of the activated carbon, and may even cause the filtering effect of the activated carbon to deteriorate in the later stage, thereby affecting the generated zero gas. In the technical solution of the present application, when calibration is required, the opening and closing part controls the opening of the air inlet, so that the ambient air is drawn into the filter pipe to generate zero gas and supply it to the detection box; while in other time periods, the opening and closing part controls the closing of the air inlet to reduce the use of activated carbon, thereby increasing the service life of the activated carbon.

[0021] Optionally, a gas semiconductor refrigeration component is further included, which is attached to the outer periphery of the main line and located on the side of the detection box close to the sampling port, and is used to cool the gas entering the detection box; the semiconductor refrigeration component includes a semiconductor refrigerator, a heat absorbing plate and a radiator, and the heat absorbing plate is located on the side of the semiconductor refrigerator close to the main line, and is used to contact the main line to cool the airflow in the main line; the radiator is located on the side of the semiconductor refrigerator away from the main line, and is used to dissipate the heat generated during the refrigeration process into the outside air.

[0022] By adopting the above solution, a semiconductor refrigeration component is provided to dissipate heat from the airflow in the main line, and the semiconductor refrigeration component is located on the side of the detection box close to the material outlet, which can cool the gas entering the detection box. Traditional gas quality monitoring equipment basically uses electrochemical sensors, and the internal temperature changes with the temperature of the external environment and cannot be adjusted. However, the operating temperature range of electrochemical sensors is limited, and they are very sensitive to temperature, requiring the temperature to be kept as stable as possible. At the same time, low humidity and high temperature will cause the electrolyte of the sensor to dry out, greatly reducing the life of the sensor. The technical solution of the present application is to provide a semiconductor refrigeration component on the periphery of the main line. Without contacting the airflow inside the main line, the heat conduction of the outer wall of the main line cools the airflow as it passes through, thereby reducing the temperature of the airflow entering the detection chamber, thereby reducing the loss of electrolyte and improving the service life of the electrochemical sensor.

[0023] Optionally, an elastic heat conducting sheet is fixedly mounted on one end of the heat absorbing plate away from the semiconductor refrigerator, and the heat conducting sheet has a clamping portion adapted to the shape of the main pipe, and the clamping portion is clamped to the outer periphery of the main pipe.

[0024] By adopting the above solution, a resilient heat-conducting sheet is provided on the semiconductor heat-absorbing plate, and the sheet has a clip-on portion adapted to the shape of the main line, thereby enabling the semiconductor refrigeration assembly to be clip-on mounted on the periphery of the main line. In the embodiment of the present application, the sheet has a clip-on portion adapted to the curved surface of the main line. The sheet's elasticity enables it to be used to cover uneven surfaces, thereby ensuring a close fit between the main line and the sheet. This clip-on installation method is relatively convenient, enabling easy disassembly and assembly of the semiconductor refrigeration assembly, simplifying the installation process while ensuring a close fit with the main line.

[0025] Optionally, there is a heat insulation layer between the detection chamber and the outer wall of the detection box, and the heat insulation layer is filled with heat insulation cotton.

[0026] By adopting the above scheme, an insulation layer is provided between the detection chamber and the detection box and insulation cotton is filled in the insulation layer, thereby ensuring the insulation effect of the detection chamber, preventing the electrochemical sensor from being affected by high temperature and reducing its life due to excessive external temperature, and further ensuring the service life of the gas detection device.

[0027] Optionally, there are multiple electrochemical sensors, and the multiple electrochemical sensors are distributed on the inner wall of the detection chamber.

[0028] By adopting the above scheme, multiple electrochemical sensors are set up and evenly distributed on the inner wall of the detection chamber, so as to detect the gas in the detection chamber; in actual use conditions, the detection accuracy of the gas detection device can be further improved and the error can be reduced by simultaneously detecting and averaging multiple electrochemical sensors.

[0029] Optionally, a flow meter is further included, which is installed inside the main pipe and is used to detect the flow rate of the airflow in the main pipe.

[0030] By adopting the above solution, a flow meter is installed in the main line to detect the flow rate of the air flow in the main line, so that the amount of gas entering the detection chamber can be detected in real time, so as to adjust the flow rate in real time by controlling the power of the air pump.

[0031] Optionally, a filter element is further included, which is fixedly installed in the main pipe and located on a side of the detection box close to the sampling port. The filter element is used to perform preliminary filtering on the airflow to be tested.

[0032] By adopting the above solution, a filter is provided in the main line, and the filter is used to perform preliminary filtration of the ambient gas to be tested. In actual working conditions, since electrochemical sensors are usually used to detect the concentration of a specified substance in the ambient airflow, other contaminants and impurities in the ambient airflow often interfere with the electrochemical sensor, and cross-contaminants affect the accuracy of detection. The present application provides a filter to filter the ambient airflow before detection, thereby reducing the impact of cross-contaminants on detection and ensuring detection accuracy.

[0033] In summary, this application has at least the following beneficial technical effects:

[0034] 1. The zero gas generator can filter the air in the external environment and convert it into zero gas, so that zero gas can be easily supplied to the detection box for calibration, which is relatively convenient. On the one hand, in the process of pumping the ambient gas for detection, long-term detection is usually not required; however, in the actual detection process, a large amount of ambient gas will inevitably remain in the pipeline and the detection box, causing the electrolyte in the electrochemical sensor to continue to react with the ambient gas, resulting in unnecessary consumption of the electrolyte and reducing the service life of the electrochemical sensor; and the residual gas produced by the reaction will affect the accuracy of the next detection. In the technical solution of the present application, by introducing standard gas zero gas into the detection pipeline, the ambient gas in the pipeline and the detection box can be discharged in time, effectively reducing the loss of electrolyte in the electrochemical sensor and ensuring the life of the gas detection device. On the other hand, due to the problem of electrolyte consumption of electrochemical sensors, electrochemical sensors will usually have zero-point drift problems after a few months of use, affecting the accuracy of subsequent detection; the existing treatment solution is usually to perform zero-point calibration through standard gas, but standard gas is difficult to obtain and the cost is high, and it is usually necessary to return to the factory for zero-point calibration, which is relatively inconvenient. In the technical solution of the present application, by providing a zero gas generator, the ambient air can be effectively converted into zero gas, and the operation of the zero gas generator is automatically controlled by a solenoid valve. Under actual working conditions, the zero gas generator is automatically controlled to generate zero gas every few months to calibrate the electrochemical sensor in the detection box, which significantly improves the convenience of calibration and effectively ensures the long-term detection accuracy and stability of the gas detection device;

[0035] 2. Fill the filter pipe with activated carbon, and use the activated carbon to filter the ambient gas in the filter pipe, thereby realizing the preparation and supply of zero gas simply and effectively. In the traditional technical solution, it is usually necessary to send it back to the factory, and use the prepared nitrogen and gases such as formaldehyde and benzene as zero gas for calibration. The preparation cost of zero gas is high and the preparation process is complicated. The technical solution of the present application filters the ambient air through activated carbon, thereby simply and effectively removing pollutants in the ambient air to form zero gas; the method of filtering with activated carbon significantly reduces the cost of zero gas preparation, thereby reducing the calibration cost of the gas detection device. In addition, in the traditional calibration process, a zero gas bottle of fixed capacity is usually used, and the bottle is filled with gas to supply zero gas. After the zero gas in the bottle is consumed, calibration cannot be performed. If the volume of the bottle is increased, it will lead to excessive space occupation. The present application can achieve long-term sustainable zero gas production by combining the filter pipe with the filling of activated carbon, thereby improving the sustainable use performance of the gas detection device;

[0036] 3. A semiconductor refrigeration component is provided to dissipate heat from the airflow in the main line, and the semiconductor refrigeration component is located on the side of the detection box close to the material outlet, and can cool the gas entering the detection box. Traditional gas quality monitoring equipment basically uses electrochemical sensors, and the internal temperature changes with the temperature of the external environment and cannot be adjusted. However, the operating temperature range of electrochemical sensors is limited, and they are very sensitive to temperature, requiring the temperature to be kept as stable as possible. At the same time, low humidity and high temperature will cause the electrolyte of the sensor to dry out, greatly reducing the life of the sensor. The technical solution of the present application is to provide a semiconductor refrigeration component on the periphery of the main line. Without contacting the airflow inside the main line, the heat conduction of the outer wall of the main line cools the airflow as it passes through, thereby reducing the temperature of the airflow entering the detection chamber, thereby reducing the loss of electrolyte and improving the service life of the electrochemical sensor. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Figure 1 It is a schematic diagram of the overall structure of an embodiment of the present application;

[0038] Figure 2 This is an overall schematic diagram of an embodiment of the present application for displaying the filtration pipe while hiding the box body;

[0039] Figure 3 This is a cross-sectional view of the detection box from a top view, made in an embodiment of the present application to illustrate the internal structure of the detection box.

[0040] Description of reference numerals:

[0041] 1. Detection pipeline; 11. Sampling port; 12. Exhaust port; 13. Main line; 131. T-joint; 14. First branch line; 141. First solenoid valve; 15. Second branch line; 151. Second solenoid valve;

[0042] 2. Air pump;

[0043] 3. Detection box; 31. Electrochemical sensor; 32. Detection chamber; 33. Thermal insulation layer;

[0044] 4. Zero air generator; 41. Box body; 42. Filter pipe; 421. Air inlet; 422. Air outlet; 423. Bend;

[0045] 5. Opening and closing parts; 51. Screw motor; 52. Sliding plate; 521. Sealing plug; 53. Guide column;

[0046] 6. Semiconductor refrigeration assembly; 61. Semiconductor refrigerator; 62. Heat absorbing plate; 63. Radiator; 64. Heat conducting sheet; 641. Clamping portion;

[0047] 7. Filter element; 8. Flow meter. DETAILED DESCRIPTION

[0048] The present application is further described in detail below with reference to the accompanying drawings.

[0049] An embodiment of the present application discloses a gas detection device that is easy to automatically calibrate.

[0050] Reference Figure 1 and Figure 2 A gas detection device that is easy to calibrate automatically includes: a detection pipeline 1, an air pump 2, a detection box 3, an electrochemical sensor 31 and a zero gas generator 4. The detection pipeline 1 has a sampling port 11 for communicating with the ambient gas and an exhaust port 12 for exhaust. The air pump 2 is connected to the detection pipeline 1 to drive the air flow to the exhaust port 12; the detection box 3 has a detection chamber 32 connected to the detection pipeline 1, the electrochemical sensor 31 is installed in the detection box 3 and contacts and detects the gas in the detection chamber 32. The zero gas generator 4 is connected to the detection pipeline 1, and the zero gas generator 4 can filter the external ambient air into zero gas and supply it to the detection chamber 32 to calibrate the electrochemical sensor 31.

[0051] Reference Figure 1 and Figure 2 The detection pipeline includes a main line 13, a first branch line 14, and a second branch line 15. The outlets of the first branch line 14 and the second branch line 15 are both connected to the inlet of the main line 13. The sampling port 11 is located at the inlet of the first branch line 14 and is covered with a sampling filter to initially filter out large particles of impurities in the air. The zero air generator 4 is connected to the inlet of the second branch line 15. Specifically, the inlet of the main line 13 is connected to a three-way connector 131, and the outlets of the first branch line 14 and the second branch line 15 are correspondingly installed on the three-way connector 131, thereby achieving communication between the first branch line 14, the second branch line 15, and the main line 13. A first solenoid valve 141 is provided on the first branch 14, and a second solenoid valve 151 is provided on the second branch 15. The gas detection device also includes a controller. The first solenoid valve 141 and the second solenoid valve 151 are both electrically connected to the controller. The controller controls the first solenoid valve 141 and the second solenoid valve 151 to control the connection and sealing of the first branch 14 and the second branch 15. The controller is not shown in the drawings of the embodiments of this application.

[0052] Reference Figure 1 and Figure 2 The gas detection device includes a working state and a calibration state. In the working state, the first solenoid valve 141 is open and the second solenoid valve 151 is closed. At the same time, the air pump 2 works to allow the air flow to be measured to enter the detection chamber 32 for detection; in the calibration state, the first solenoid valve 141 is closed and the second solenoid valve 151 is opened. At the same time, the air pump 2 works to allow the ambient air to be filtered by the zero gas generator 4 to form zero gas, and supply it to the detection chamber 32 to calibrate the electrochemical sensor 31.

[0053] Reference Figure 2 and Figure 3 The zero air generator 4 includes a box body 41 and a filter pipe 42 installed inside the box body 41. The filter pipe 42 has an air inlet 421 and an air outlet 422. The air inlet 421 is connected to the external ambient air, and the air outlet 422 is connected to the second branch 15. The filter pipe 42 is filled with activated carbon, which is pressed into the filter pipe 42 to filter the ambient air flow passing through to form zero air. In other embodiments, some other target selective isolation layers can also be used, such as any of filter paper, filter membrane, molecular sieve, filter device and covering structure formed by filling and pressing selective filter material, which will not be described in detail here.

[0054] Reference Figure 2 and Figure 3 Specifically, a first through hole is formed through the side wall of the lower end of the box body 41, and a second through hole is formed through the side wall of the upper end of the box body 41. One end of the filter duct 42, where the air inlet 421 is located, is extended from the first through hole to the outside of the box body 41 to communicate with the ambient air; one end of the filter duct 42, where the air outlet 422 is located, is extended from the second through hole to the outside of the box body 41 to communicate with the second branch 15. The filter duct 42 is bent multiple times inside the box body 41 to form multiple bends 423, and the rotation angle of the bends 423 is 180 degrees. It is worth mentioning that a filter screen is provided inside the air outlet 422 of the filter duct 42. The pore size of the filter screen is smaller than the particle size of the activated carbon to prevent the activated carbon from entering the main duct with the air flow.

[0055] Reference Figure 2 and Figure 3 The zero-gas generating device is provided with an opening and closing member 5 for opening and closing the air inlet 421 of the filter duct 42. The opening and closing member 5 is mounted at the air inlet 421 of the filter duct 42 and operates to open or close the air inlet 421 of the filter duct 42. Specifically, the opening and closing member 5 includes a screw motor and a sliding disk 52. The filter duct 42 is arranged horizontally at the air inlet 421. The screw motor is fixedly mounted on the side wall of the box body 41 and the screw is arranged horizontally. The sliding disk 52 is threadedly connected to the screw of the screw motor. The screw motor operates to drive the sliding disk 52 to move horizontally. An elastic sealing plug 521 is fixedly mounted on one end of the sliding disk 52 near the box body 41. The shape of the sealing plug 521 is adapted to the opening size of the air inlet 421 of the filter duct 42. The sliding disk 52 can move horizontally toward the box body 41 to insert the sealing plug 521 into the air inlet 421 of the filter duct 42 with an interference fit. It is worth mentioning that the opening and closing member 5 further includes a guide column 53 fixedly mounted on the box body 41 along the horizontal direction, and the sliding plate 52 is slidably inserted into the guide column 53 , and the guide column 53 is used to guide the horizontal movement of the sliding plate 52 .

[0056] Reference Figure 2 and Figure 3 The gas detection device also includes a semiconductor refrigeration component 6, which is attached to the outer periphery of the main line 13 and is located on the side of the detection box 3 close to the sampling port 11. Specifically, the semiconductor refrigeration component 6 is located between the air pump 2 and the detection box 3 to cool the airflow flowing to the detection box 3. The semiconductor refrigeration component 6 includes a semiconductor refrigerator 61, a heat absorbing plate 62 and a radiator 63. In the embodiment of the present application, the semiconductor refrigerator 61 is a plate-shaped structure, the heat absorbing plate 62 is fixedly mounted on the cooling end plate surface of the semiconductor refrigerator 61, and the radiator 63 is fixedly mounted on the heat dissipation end plate surface of the semiconductor refrigerator 61. Specifically, the heat absorbing plate 62 is located on the side of the semiconductor refrigerator 61 close to the main line 13, and the heat absorbing plate 62 is disconnected from the main line 13 to cool and cool the airflow in the main line 13; the radiator 63 is located on the side of the semiconductor refrigerator 61 away from the main line 13, and the radiator 63 is disconnected from the ambient air to dissipate the heat generated at the heat dissipation end during the cooling process to the outside air.

[0057] Reference Figure 2 and Figure 3 An elastic heat-conducting sheet 64 is fixedly mounted on one end of the heat-absorbing plate 62 away from the semiconductor cooler 61. The heat-conducting sheet 64 has a clamping portion 641 adapted to the shape of the main line 13, and the clamping portion 641 is clamped to the outer periphery of the main line 13. In the embodiment of the present application, the main line 13 is cylindrical, and the clamping portion 641 is an arc-shaped portion adapted to the outer wall of the main line 13. When the clamping portion 641 is clamped to the outer wall of the main line 13, the arc-shaped clamping portion 641 elastically deforms and clamps to the main line 13 to achieve a detachable connection between the semiconductor refrigeration component 6 and the main line 13. It is worth mentioning that the heat-absorbing plate 62 has the advantages of high compressibility, softness and elasticity, and good thermal conductivity, and can efficiently and fully transfer the heat on the main line 13 to the semiconductor cooler 61.

[0058] Reference Figure 2 and Figure 3 The gas detection device further includes a filter element 7 and a flowmeter 8. The filter element 7 is fixedly mounted within the main conduit 13 and is located on the side of the detection box 3 near the sampling port 11. Specifically, the filter element 7 is located between the semiconductor refrigeration assembly 6 and the air pump 2. The filter element 7 is used to perform preliminary filtering on the airflow to be tested, thereby filtering out impurities that do not require detection by the electrochemical sensor 31. The flowmeter 8 is located between the detection box 3 and the semiconductor refrigeration assembly 6 and is installed within the main conduit 13 to monitor the flow rate of the airflow in the main conduit 13 in real time.

[0059] Reference Figure 2 and Figure 3An insulating layer 33 is provided between the outer wall of the detection box 3 and the hollow detection chamber 32 inside. The insulating layer 33 is filled with insulating cotton, which is not shown in the figure. There are multiple electrochemical sensors 31, and the multiple electrochemical sensors 31 are evenly distributed on the inner wall of the detection chamber 32. Specifically, in the embodiment of the present application, the detection chamber 32 has four side walls, and the number of electrochemical sensors 31 is 8, with two electrochemical sensors 31 arranged on each side wall. The electrochemical sensors 31 are all electrically connected to the controller.

[0060] The implementation principle of a gas detection device that facilitates automatic calibration in an embodiment of the present application is as follows: the detection pipeline includes a first branch 14 and a second branch 15, the first branch 14 being connected to the ambient air, and the second branch 15 being connected to the zero gas generator 4. Under normal circumstances, the air pump 2 operates to extract ambient gas through the first branch 14 and delivers it to the detection box 3 for detection. When calibration of the electrochemical sensor 31 is required, the air pump 2 operates to extract ambient gas through the second branch 15, converts it into zero gas through the activated carbon in the filter pipe 42, and delivers it to the detection box 3 to calibrate the electrochemical sensor 31 and ensure its detection accuracy.

[0061] The examples of this specific embodiment are all preferred embodiments of this application and are not intended to limit the scope of protection of this application. Identical components are represented by the same reference numerals. Therefore, any equivalent changes made based on the structure, shape, and principle of this application should be included in the scope of protection of this application.

Claims

1. A gas detection device that is easy to automatically calibrate, characterized in that: include: A detection pipeline (1), the detection pipeline (1) having a sampling port (11) connected to the ambient gas to be detected and an exhaust port (12) for exhausting gas; an air pump (2) connected to the detection pipeline (1) and used to drive the air flow in the detection pipeline (1) to flow toward the exhaust port (12); A detection box (3) having a hollow detection chamber (32) therein, wherein the detection chamber (32) is connected to the detection pipe (1); an electrochemical sensor (31), the electrochemical sensor (31) being fixedly mounted in the detection box (3) and configured to perform contact detection on the gas in the detection chamber (32); A zero air generator (4) is connected to the detection pipeline (1) and is used to filter and convert external air into zero air; The detection pipeline comprises a main line (13), a first branch line (14) and a second branch line (15); a first electromagnetic valve (141) is installed on the first branch line (14), and a second electromagnetic valve (151) is installed on the second branch line (15); the gas outlet ends of the first branch line (14) and the second branch line are both connected to the main line (13); the sampling port (11) is located at the gas inlet end of the first branch line (14); and the zero gas generator (4) is connected to the gas inlet end of the second branch line (15). The gas detection device includes an operating state for detecting a gas flow to be detected and a calibration state for calibrating an electrochemical sensor (31). In the operating state, the first solenoid valve (141) is opened and the second solenoid valve (151) is closed, and the gas flow to be detected enters the detection chamber (32) for detection. In the calibration state, the first solenoid valve (141) is closed and the second solenoid valve (151) is opened, and the zero gas generator (4) supplies zero gas to the detection chamber (32) to calibrate the electrochemical sensor (31). The zero air generator (4) comprises a filter pipe (42) and activated carbon filled in the filter pipe (42), the filter pipe (42) having an air inlet (421) and an air outlet (422), the air inlet (421) being connected to the outside air, and the air outlet (422) being connected to the second branch (15); The filter pipe (42) is bent multiple times to form a plurality of bent portions (423); The zero air generator is provided with an opening and closing member (5), the opening and closing member (5) is installed at the air inlet (421) of the filter pipe (42), and the opening and closing member (5) works to open or close the air inlet (421) of the filter pipe (42); The device further comprises a gas semiconductor refrigeration assembly (6), the semiconductor refrigeration assembly (6) being attached to the outer periphery of the main line (13) and being located on a side of the detection box (3) close to the sampling port (11), the semiconductor refrigeration assembly (6) being used to cool the gas entering the detection box (3); the semiconductor refrigeration assembly (6) comprising a semiconductor refrigerator (61), a heat absorbing plate (62) and a radiator (63); the heat absorbing plate (62) being located on a side of the semiconductor refrigerator (61) close to the main line (13) and being used to contact the main line (13) to cool the air flow in the main line (13); the radiator (63) being located on a side of the semiconductor refrigerator (61) away from the main line (13) and being used to dissipate heat generated during the refrigeration process into the outside air; It also includes a filter element (7), which is fixedly installed in the main pipe (13). The filter element (7) is located on a side of the detection box (3) close to the sampling port (11), and is used to perform preliminary filtering on the airflow to be tested.

2. A gas detection device that is easy to automatically calibrate according to claim 1, characterized in that: An elastic heat-conducting sheet (64) is fixedly mounted on one end of the heat-absorbing plate (62) away from the semiconductor cooler (61); the heat-conducting sheet (64) has a clamping portion (641) adapted to the shape of the main pipe (13); and the clamping portion (641) is clamped to the outer periphery of the main pipe (13).

3. A gas detection device that facilitates automatic calibration according to claim 1, characterized in that: A heat insulation layer (33) is provided between the detection chamber (32) and the outer wall of the detection box (3), and the heat insulation layer (33) is filled with heat insulation cotton.

4. A gas detection device that facilitates automatic calibration according to claim 1, characterized in that: There are multiple electrochemical sensors (31), and the multiple electrochemical sensors (31) are evenly distributed on the inner wall of the detection chamber (32).

5. A gas detection device that is easy to automatically calibrate according to claim 1, characterized in that: It also includes a flow meter (8), which is installed inside the main pipe (13) and is used to detect the flow rate of the airflow in the main pipe (13).

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