Method and device for testing a gas sensor

Abstract

The application discloses a kind of test method and test device of gas sensor, belong to sensor test technical field.Method includes: by each fan speed regulator, each fan is adjusted to target wind speed, make each fan run target length of time;In the state that each fan keeps running, by gas injection component, target volume of test gas is injected into sealed cabin body;In the case where test gas injection is completed, according to the reading of each gas sensor in sealed cabin body, the wind speed of each fan is adjusted, and the alarm response time of each gas sensor, the target reading value when reading is in stable state and the time reaching target reading value preset proportion are recorded.The application can shorten the time required for test gas concentration homogenization, adjust the concentration distribution of gas in the cabin during the test, so that the gas sensor at each installation site can be tested in a uniform and stable concentration field, not only realizing multi-sensor batch testing, but also improving the accuracy of gas sensor testing.

Description

Technical Field

[0001] This application belongs to the field of sensor testing technology, and in particular relates to a testing method and testing device for a gas sensor. Background Technology

[0002] In fields such as coal mine safety, petrochemicals, gas pipeline monitoring, and home security, gas sensors are needed to detect hazardous gases such as carbon monoxide (CO) and methane (CH4). The performance of the gas sensor determines the reliability of hazardous gas leak warnings; therefore, gas sensors must be tested before being put into use.

[0003] In related technologies, static diffusion is commonly used to test gas sensors. This involves injecting the gas to be tested into a sealed test chamber and allowing the gas to diffuse naturally to achieve concentration homogenization. However, because the natural diffusion rate is slow and the concentration field takes a long time to establish, the gas sensor is affected by the diffusion process, resulting in lower test accuracy. Summary of the Invention

[0004] This application aims to address at least one of the technical problems existing in the prior art. To this end, this application proposes a testing method and apparatus for gas sensors to improve the accuracy of gas sensor testing.

[0005] In a first aspect, this application provides a testing method for a gas sensor, applied to a testing device. The testing device includes: a sealed chamber with multiple mounting positions for fixing the gas sensor inside, and multiple fans; wherein each fan has a corresponding wind speed regulator; a gas injection assembly, connected to the sealed chamber, for injecting test gas into the sealed chamber; the method includes: Each fan is adjusted to the target wind speed by using each wind speed regulator, so that each fan can run for the target time. With all fans running, a target volume of test gas is injected into the sealed chamber through the gas injection assembly. After the test gas injection is completed, adjust the wind speed of each fan according to the readings of each gas sensor in the sealed chamber, and record the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach the preset proportion of the target reading value.

[0006] According to the gas sensor testing method of this application, a target volume of test gas is injected into the sealed chamber while each fan is running. The convection of multiple fans accelerates the diffusion and uniform mixing of the test gas in the sealed chamber, shortening the time required for homogenization of the test gas concentration. This allows the gas sensor to be in a stable testing environment more quickly. Furthermore, by dynamically adjusting the wind speed of each fan based on the readings of each gas sensor, the concentration distribution of the gas in the chamber can be adjusted during the test, enabling the gas sensors at each installation position to be tested in a uniform and stable concentration field. This not only realizes batch testing of multiple sensors but also improves the accuracy of gas sensor testing.

[0007] According to one embodiment of this application, adjusting the wind speed of each fan based on the readings of each gas sensor within the sealed chamber includes: If the difference between the readings of any two gas sensors is greater than the target threshold, the wind speed of each fan is increased by each wind speed regulator.

[0008] In this embodiment, by increasing the fan speed when there are large differences in the readings of gas sensors at different locations, the airflow can be increased, the gas exchange between high-concentration and low-concentration areas can be accelerated, the test deviation caused by uneven gas mixing can be reduced, and the uniformity of gas concentration distribution in the test environment and the accuracy of gas sensor testing can be improved.

[0009] According to one embodiment of this application, adjusting the wind speed of each fan based on the readings of each gas sensor within the sealed chamber includes: If the fluctuation range of the reading of any gas sensor exceeds the first target range, the wind speed of each fan is reduced by each wind speed regulator.

[0010] In this embodiment, by reducing the fan speed when the gas sensor reading fluctuates significantly, the intensity of the airflow can be weakened, the gas concentration around the sensor can be stabilized, the interference of the airflow on the sensor can be reduced, and the accuracy of the gas sensor test can be further improved.

[0011] According to one embodiment of this application, the gas injection assembly includes an injection device, a first conduit, and a second conduit; The injection device is connected to the gas source through the first pipeline and to the sealed chamber through the second pipeline.

[0012] In this embodiment, the injection device is connected to the gas source through the first pipeline to obtain the test gas, and the injection device is connected to the sealed chamber through the second pipeline to inject a quantitative amount of test gas into the chamber. This realizes the separation of the gas acquisition and injection process, and improves the accuracy and safety of the test gas delivery.

[0013] According to one embodiment of this application, the gas injection assembly further includes a gas pipe connector, a first switch assembly disposed in the first pipeline, and a second switch assembly disposed in the second pipeline; The injection device is connected to the first and second pipelines via a tracheal connector.

[0014] In this embodiment, the injection device is connected to the first pipeline and the second pipeline respectively through the air pipe connector, and a first switch assembly is set in the first pipeline and a second switch assembly is set in the second pipeline. This allows for independent control of the gas supply on the gas source side and the gas injection on the chamber side, thereby improving the accuracy of the test gas injection volume control and the convenience of the test operation.

[0015] According to one embodiment of this application, injecting a target volume of test gas into a sealed chamber via a gas injection assembly includes: Open the valve of the gas source and turn on the first switch assembly. Draw the test gas through the injection device and turn off the first switch assembly when the test gas in the injection device reaches the target volume. Turn on the second switch assembly, inject test gas into the sealed chamber through the injection device, and turn off the second switch assembly after injecting the target volume of test gas.

[0016] In this embodiment, by first opening the gas source valve and the first switch assembly, the test gas is extracted from the gas source using the injection device, and the first switch assembly is closed when the test gas in the injection device reaches the target volume. By opening the second switch assembly, the test gas in the injection device is injected into the sealed chamber, and the second switch assembly is closed after the injection is completed. This allows for accurate control of the volume of the extracted test gas and the volume of the injected test gas.

[0017] According to one embodiment of this application, the method further includes: The performance of each gas sensor is evaluated based on its alarm response time, target reading value when the reading is stable, and the time to reach a preset percentage of the target reading value.

[0018] In this embodiment, by correlating the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach the preset proportion of the target reading value, the requirements of gas sensors on response speed, measurement accuracy, and stability in actual application scenarios are fully considered, thereby improving the accuracy of gas sensor performance evaluation.

[0019] According to one embodiment of this application, the number of fans is two, and the two fans are symmetrically arranged on the inner wall of the sealed chamber.

[0020] In this embodiment, two symmetrically arranged fans can form opposing or complementary airflow paths, creating a circulating convection field inside the cabin, thereby reducing the gas concentration gradient inside the cabin and improving the consistency of test conditions for each gas sensor.

[0021] According to one embodiment of this application, each wind speed regulator includes multiple wind speed settings, with different wind speed settings corresponding to different wind speeds of the fan.

[0022] In this embodiment, by setting multiple wind speed levels, each corresponding to a different wind speed of the fan, the wind speed of different fans can be accurately adjusted during the test, further improving the consistency of the test conditions.

[0023] Secondly, this application provides a testing apparatus for a gas sensor, comprising: The sealed chamber contains multiple mounting positions for fixing gas sensors and multiple fans; each fan is equipped with a wind speed regulator. The gas injection assembly, connected to the sealed chamber, is used to inject test gas into the sealed chamber. A controller for performing the test method for the gas sensor as described in the first aspect above.

[0024] According to the gas sensor testing device of this application, by injecting a target volume of test gas into the sealed chamber while each fan is running, the convection of multiple fans accelerates the diffusion and uniform mixing of the test gas in the sealed chamber, shortening the time required for homogenization of the test gas concentration. This allows the gas sensor to be in a stable testing environment more quickly. Furthermore, by dynamically adjusting the wind speed of each fan according to the readings of each gas sensor, the concentration distribution of the gas in the chamber can be adjusted during the test, enabling the gas sensors at each installation position to be tested in a uniform and stable concentration field. This not only realizes batch testing of multiple sensors but also improves the accuracy of gas sensor testing.

[0025] The above-described one or more technical solutions in the embodiments of this application have at least one of the following technical effects: According to the gas sensor testing method of this application, a target volume of test gas is injected into the sealed chamber while each fan is running. The convection of multiple fans accelerates the diffusion and uniform mixing of the test gas in the sealed chamber, shortening the time required for homogenization of the test gas concentration. This allows the gas sensor to be in a stable testing environment more quickly. Furthermore, by dynamically adjusting the wind speed of each fan based on the readings of each gas sensor, the concentration distribution of the gas in the chamber can be adjusted during the test, enabling the gas sensors at each installation position to be tested in a uniform and stable concentration field. This not only realizes batch testing of multiple sensors but also improves the accuracy of gas sensor testing.

[0026] In some embodiments, by increasing the fan speed when there are large differences in the readings of gas sensors at different locations, the airflow can be increased, the gas exchange between high-concentration and low-concentration areas can be accelerated, the test deviation caused by uneven gas mixing can be reduced, and the uniformity of gas concentration distribution in the test environment and the accuracy of gas sensor testing can be improved.

[0027] In some embodiments, by reducing the fan speed when the gas sensor reading fluctuates significantly, the intensity of the airflow can be weakened, the gas concentration around the sensor can be stabilized, the interference of the airflow on the sensor can be reduced, and the accuracy of the gas sensor test can be further improved.

[0028] In some embodiments, the injection device is connected to a gas source through a first pipeline to acquire test gas, and the injection device is connected to a sealed chamber through a second pipeline to inject a fixed amount of test gas into the chamber. This separates the gas acquisition and injection processes, improving the accuracy and safety of test gas delivery.

[0029] In some embodiments, the injection device is connected to a first pipeline and a second pipeline respectively through a gas pipe connector, and a first switch assembly is provided in the first pipeline and a second switch assembly is provided in the second pipeline. This enables independent control of the gas supply on the gas source side and the gas injection on the chamber side, thereby improving the accuracy of the test gas injection volume control and the convenience of the test operation.

[0030] In some embodiments, by first opening the gas source valve and the first switch assembly, the test gas is extracted from the gas source using the injection device, and the first switch assembly is closed when the test gas in the injection device reaches the target volume. By opening the second switch assembly, the test gas in the injection device is injected into the sealed chamber, and the second switch assembly is closed after the injection is completed, the volume of the extracted test gas and the volume of the injected test gas can be accurately controlled.

[0031] In some embodiments, by performing correlation analysis on the alarm response time of each gas sensor, the target reading value when the reading is in a stable state, and the time to reach a preset proportion of the target reading value, the requirements of gas sensors on response speed, measurement accuracy, and stability in actual application scenarios are fully considered, thereby improving the accuracy of gas sensor performance evaluation.

[0032] In some embodiments, two symmetrically arranged fans can form opposing or complementary airflow paths, creating a circulating convection field inside the cabin, thereby reducing the gas concentration gradient inside the cabin and improving the consistency of test conditions for each gas sensor.

[0033] In some embodiments, by setting multiple wind speed levels, each corresponding to a different wind speed of the fan, the wind speed of different fans can be accurately adjusted during the test, further improving the consistency of test conditions.

[0034] Additional aspects and advantages of this application will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of this application. Attached Figure Description

[0035] The above and / or additional aspects and advantages of this application will become apparent and readily understood in conjunction with the following description of the embodiments in conjunction with the accompanying drawings, wherein: Figure 1 This is a schematic diagram of the structure of the testing device for the gas sensor provided in the embodiments of this application; Figure 2 This is a schematic flowchart of the testing method for the gas sensor provided in the embodiments of this application. Detailed Implementation

[0036] The technical solutions of the embodiments of this application will be clearly described below with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application are within the scope of protection of this application.

[0037] The terms "first," "second," etc., used in the specification and claims of this application are used to distinguish similar objects and not to describe a specific order or sequence. It should be understood that such use of data can be interchanged where appropriate so that embodiments of this application can be implemented in orders other than those illustrated or described herein, and the objects distinguished by "first," "second," etc., are generally of the same class and the number of objects is not limited; for example, a first object can be one or more. Furthermore, in the specification and claims, "and / or" indicates at least one of the connected objects, and the character " / " generally indicates that the preceding and following objects are in an "or" relationship.

[0038] The testing method and testing device for the gas sensor provided in this application will be described in detail below with reference to the accompanying drawings, through specific embodiments and application scenarios.

[0039] A gas sensor is a detection device that converts the concentration information of a specific gas into a recognizable electrical signal. The working principle of a gas sensor is based on the physical or chemical interaction between a gas-sensitive material and target gas molecules. When target gas molecules are adsorbed onto the surface of the gas-sensitive material, they cause changes in physical parameters such as the material's resistance, capacitance, mass, or optical properties. These changes are converted into electrical signals such as voltage, current, or frequency by a signal conditioning circuit, thus determining the gas concentration. Types of gas sensors include semiconductor, electrochemical, catalytic combustion, infrared absorption, and metal oxide semiconductor types.

[0040] Gas sensors are widely used in coal mine safety, petrochemicals, gas pipeline monitoring, home security, industrial production, and environmental protection. In different fields, different types of gas sensors can detect the concentration of different gases. For example, in coal mine safety, flammable, explosive, or toxic gases such as methane (CH4) and carbon monoxide (CO) exist in the underground working environment. Gas sensors can be installed in mining faces, roadways, and ventilation systems to detect the concentration of methane and carbon monoxide. In the petrochemical industry, oil refining and chemical production processes involve large amounts of volatile organic compounds (VOCs) and hydrogen sulfide (H2S) and other hazardous gases. Gas sensors can be installed in production units, storage tank areas, and pipeline interfaces to monitor for leaks. In home security, in kitchens, gas stoves, gas water heaters, and other appliances may leak natural gas or liquefied petroleum gas due to aging hoses, loose connections, or improper operation. Gas sensors can be installed in kitchen appliances such as stoves and range hoods, or in kitchen ceilings or walls, to detect the concentration of combustible gases in the air.

[0041] The performance of a gas sensor determines the reliability of a hazardous gas leak warning; therefore, a gas sensor needs to be tested before it is put into use.

[0042] like Figure 1 As shown, this application embodiment provides a testing device 100, including: a sealed chamber 110, with multiple mounting positions 120 for fixing gas sensors inside, and multiple fans 130; wherein each fan 130 corresponds to a wind speed regulator 140; and a gas injection assembly 150, which is connected to the sealed chamber 110 and is used to inject test gas into the sealed chamber 110.

[0043] In this embodiment of the application, the sealed chamber 110 is used to provide a closed test environment for testing. The sealed chamber 110 can be made of a material with good airtightness and chemical inertness. For example, the sealed chamber 110 can be integrally molded from transparent acrylic material.

[0044] The sealed chamber 110 has multiple mounting positions 120 for fixing gas sensors inside. Each mounting position 120 is arranged along the side wall or bottom wall of the sealed chamber 110, or it can be evenly distributed in different positions within the sealed chamber 110. Each mounting position 120 can fix one gas sensor.

[0045] Multiple fans 130 are also installed inside the sealed chamber 110. Forced convection is generated by each fan 130 to accelerate the diffusion and mixing of the test gas within the sealed chamber 110. The arrangement of each fan 130 within the sealed chamber 110 can be pre-set; for example, they can be evenly distributed along the circumference of the sealed chamber 110 or arranged in layers to form an airflow circulation path covering the chamber space, reducing dead zones in gas concentration distribution.

[0046] In some embodiments, the number of fans 130 is two, and the two fans 130 are symmetrically arranged on the inner wall of the sealed chamber 110. For example, the two fans 130 can be symmetrically arranged on the left and right sides of the sealed chamber 110 to form a stable, dead-angle-free lateral convection, making the concentration inside the chamber more uniform; they can also be arranged in other positions, such as the two fans 130 being arranged at the top and bottom of the sealed chamber 110, or at the front and rear sides of the sealed chamber 110, etc.

[0047] Of course, the two fans 130 can also be set at different heights on the same side of the sealed chamber 110, and this application embodiment does not limit this.

[0048] In this embodiment, two symmetrically arranged fans can form opposing or complementary airflow paths, creating a circulating convection field inside the cabin, thereby reducing the gas concentration gradient inside the cabin and improving the consistency of test conditions for each gas sensor.

[0049] Each fan 130 is equipped with a corresponding wind speed regulator 140, which is used to independently control the speed of the corresponding fan 130.

[0050] Each wind speed regulator 140 can be connected to each fan via wires. For example, each wind speed regulator 140 is located outside the sealed chamber 110. While ensuring airtightness, the connecting wire passes through the sealed chamber 110 to connect the wind speed regulator 140 and the fan 130.

[0051] Each wind speed regulator 140 can also be installed inside the sealed chamber 110, and the wind speed regulator 140 can be wirelessly controlled to adjust the wind speed of the fan 130.

[0052] In some embodiments, the wind speed regulator 140 includes multiple wind speed settings, each corresponding to a different wind speed of the fan. For example, the wind speed settings may include low, medium, and high, where low corresponds to a low fan speed, medium corresponds to a medium fan speed, and high corresponds to a high fan speed. However, the fan settings may include even more different settings, and this embodiment does not limit this.

[0053] Based on the gas concentration distribution and sensor reading changes within the sealed chamber 110 during the test, the operating speed of the corresponding fan 130 can be adjusted in real time to ensure that the environment of each gas sensor is consistent.

[0054] In this embodiment, by setting multiple wind speed levels, each corresponding to a different wind speed of the fan, the wind speed of different fans can be accurately adjusted during the test, further improving the consistency of the test conditions.

[0055] The gas injection assembly 150 is connected to the sealed chamber 110 and is used to inject test gas into the sealed chamber 110. The gas injection assembly 150 may include components such as an injection pipeline and a gas collection device. The gas collection device is used to contain the test gas, and the gas collection device is connected to one end of the injection pipeline, while the other end of the injection pipeline is connected to the sealed chamber 110.

[0056] In some embodiments, the outlet of the gas injection pipeline can be located on the air inlet side of the blower 130 or at the beginning of the airflow circulation path, so that the injected test gas can be quickly dispersed into the cabin space under the action of the airflow generated by the blower 130.

[0057] In some embodiments, the testing apparatus 100 may further include a controller, which can be used to execute the testing method for the gas sensor provided in the embodiments of this application.

[0058] like Figure 2 As shown, the testing method for the gas sensor in this application embodiment includes steps 210, 220 and 230.

[0059] Step 210: Adjust each fan 130 to the target wind speed through each wind speed regulator 140, so that each fan 130 runs for the target time.

[0060] Before testing, the gas sensor to be tested can be fixed inside the inspection sealed chamber 110 through the mounting position, and the airtightness of the sealed chamber 110 can be checked. The signal of the gas sensor can be led out through the cable hole on the sealed chamber 110 and connected to the data acquisition device.

[0061] In this embodiment of the application, after the test preparation is completed, each fan 130 can be adjusted to the target wind speed by each wind speed regulator 140, so that each fan 130 can run continuously for the target time, thereby establishing a stable airflow field in the sealed chamber 110 in advance before the test, so that the original air in the chamber can be fully circulated and mixed, reducing the initial airflow disturbance caused by factors such as chamber structure and uneven temperature distribution.

[0062] The target wind speed refers to the pre-set fan speed that enables effective airflow circulation within the sealed chamber 110. For example, the target wind speed could be the wind speed corresponding to the medium setting, or it could be a pre-calibrated wind speed. The target duration can be determined based on factors such as the volume of the sealed chamber 110, the air volume of the fan 130, and the diffusion characteristics of the test gas. For example, the target duration could be 2 minutes, 3 minutes, 5 minutes, or other times.

[0063] In some embodiments, the target wind speeds corresponding to each fan can be the same or different. For example, all fans can be uniformly adjusted to the same target wind speed, or different target wind speeds can be set according to the installation position of the fans. For example, the target wind speed of the fans 130 arranged in the corners or edges of the cabin can be set higher than that of the fans 130 in the center position to compensate for the insufficient airflow circulation power in the edge area, thereby making the airflow distribution in the cabin space more uniform.

[0064] Step 220: With each fan 130 running, inject the target volume of test gas into the sealed chamber 110 through the gas injection assembly 150.

[0065] In this embodiment of the application, the target volume can be calculated based on the gas concentration required for the test and the volume of the sealed chamber 110, or it can be a preset value.

[0066] The test gas can be carbon monoxide, methane, volatile organic compounds, hydrogen sulfide, etc. The embodiments of this application do not limit the type of test gas.

[0067] During the injection of test gas, each blower 130 remains operational. The injected test gas is dispersed by the convection generated by the blowers 130 and mixes with the existing air in the chamber.

[0068] In some embodiments, the gas injection assembly 150 may contain a target volume of test gas collected in advance. The gas injection assembly 150 may also be connected to a gas source 160 to obtain the target volume of test gas and inject the test gas into the sealed chamber 110 through an injection pipeline connected to the sealed chamber 110.

[0069] In some embodiments, the outlet of the gas injection line can be designed as a porous structure or an atomizing nozzle to increase the contact area between the test gas and air and accelerate the mixing process.

[0070] Step 230: After the test gas injection is completed, adjust the wind speed of each fan 130 according to the readings of each gas sensor in the sealed chamber 110, and record the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach the preset proportion of the target reading value.

[0071] In this embodiment of the application, after the test gas is injected, the real-time readings of the gas sensors at each installation position 120 inside the sealed chamber 110 can be read, wherein the readings of the gas sensors represent the concentration of the detected test gas.

[0072] Due to differences in cabin structure, airflow distribution, and the response characteristics of the gas sensors themselves, the readings of each gas sensor may deviate. If the reading of a certain gas sensor is lower than the readings of other sensors by a certain value, it indicates that the gas concentration in the area where that gas sensor is located may be low. This can be addressed by increasing the wind speed of the corresponding fan 130, or by increasing the wind speed of all fans 130, thereby enhancing the airflow circulation within the cabin, promoting the transport of gas from high-concentration areas to low-concentration areas, improving the uniformity of gas distribution within the cabin, and enabling the gas sensors at each installation position 120 to be tested in a uniform and stable concentration field.

[0073] In some embodiments, the average value of the readings of each gas sensor can be used as a reference value. The difference between the readings of each gas sensor and the reference value can be calculated, and the wind speed of each fan 130 can be adjusted according to the magnitude of the difference. For example, when the reading of any gas sensor is more than 5% lower or higher than the reference value, the wind speed of each fan 130 is increased; when the readings of all gas sensors rise and are within 5% lower or higher than the reference value, the wind speed of each fan 130 is not adjusted.

[0074] In this embodiment of the application, timing can be started after the test gas injection is completed, and the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach the preset proportion of the target reading value can be recorded.

[0075] Alarm response time refers to the time from the completion of test gas injection, when the concentration data detected by the gas sensor is greater than or equal to the preset alarm threshold, to the first triggering of an alarm (such as outputting an audible and visual alarm). Alarm response time is an indicator of the sensitivity and dynamic response characteristics of a gas sensor; the shorter the response time, the faster the gas sensor detects hazardous gases.

[0076] The target reading refers to the output value of a gas sensor when its reading is in a stable state. When the variation in the sensor reading over multiple consecutive sampling periods is less than a preset threshold (e.g., fluctuation ≤ ±2%), the reading is considered to have reached a stable state, and this reading is the target reading. The target reading reflects the sensor's output accuracy under stable concentration conditions and can be used to evaluate the static performance indicators of a gas sensor, such as linearity and repeatability.

[0077] The time required to reach a preset percentage of the target reading refers to the time required for the gas sensor reading to rise from its initial value to a preset percentage (e.g., 90%, or T90 time) of the target reading. T90 time is a common evaluation metric for gas sensor response time, objectively reflecting the sensor's dynamic response speed. By recording T90 time, it is possible to compare the dynamic performance differences between different sensors or the same sensor under different test conditions.

[0078] Of course, the preset ratio can also be selected according to the test requirements, such as T50 (50%), T80 (80%) or T95 (95%), etc., and this application embodiment does not limit this.

[0079] According to the gas sensor testing method of this application, a target volume of test gas is injected into the sealed chamber while each fan is running. The convection of multiple fans accelerates the diffusion and uniform mixing of the test gas in the sealed chamber, shortening the time required for homogenization of the test gas concentration. This allows the gas sensor to be in a stable testing environment more quickly. Furthermore, by dynamically adjusting the wind speed of each fan based on the readings of each gas sensor, the concentration distribution of the gas in the chamber can be adjusted during the test, enabling the gas sensors at each installation position to be tested in a uniform and stable concentration field. This not only realizes batch testing of multiple sensors but also improves the accuracy of gas sensor testing.

[0080] In some embodiments, adjusting the wind speed of each fan 130 based on the readings of each gas sensor within the sealed chamber 110 includes: If the difference between the readings of any two gas sensors is greater than the target threshold, the wind speed of each fan 130 is increased by each wind speed regulator 140.

[0081] In this embodiment, after acquiring the readings of each gas sensor, the difference between the readings of each gas sensor can be calculated. If the difference between the readings of two gas sensors is greater than a target threshold, it indicates that the gas distribution within the sealed chamber 110 is uneven. The wind speed of each fan 130 can be increased to enhance the airflow circulation intensity within the chamber, accelerate gas exchange between high-concentration and low-concentration areas, and promote a more uniform concentration distribution. In this embodiment, the adjustment level and adjustment time can also be recorded.

[0082] The target threshold is a pre-set critical value used to determine whether the concentration field has reached a uniform state. The specific value of the target threshold can be determined based on factors such as the test accuracy requirements, sensor range, and allowable error range. For example, for a methane sensor with a range of 0-10000ppm, the target threshold can be set to 5% of the full scale, i.e., 500ppm.

[0083] In some embodiments, the increase in wind speed can be determined based on the magnitude of the difference; for example, the larger the difference, the greater the increase in wind speed.

[0084] In this embodiment, by increasing the fan speed when there are large differences in the readings of gas sensors at different locations, the airflow can be increased, the gas exchange between high-concentration and low-concentration areas can be accelerated, the test deviation caused by uneven gas mixing can be reduced, and the uniformity of gas concentration distribution in the test environment and the accuracy of gas sensor testing can be improved.

[0085] In some embodiments, adjusting the wind speed of each fan 130 based on the readings of each gas sensor within the sealed chamber 110 includes: If the reading fluctuation of any gas sensor exceeds the first target amplitude, the wind speed of each fan 130 is reduced by each wind speed regulator 140.

[0086] In this embodiment, the reading fluctuation range refers to the range of change in the gas sensor readings within a certain time window, which can be represented by the range or standard deviation of the readings within that time window. If the reading fluctuation range of any gas sensor exceeds the first target range, it indicates that the airflow within the chamber is too turbulent. Excessive airflow disturbance causes drastic changes in gas concentration at the gas sensor probe, thus affecting the gas sensor's perception of gas concentration. The first target range can be preset; for example, it can be a fixed value, such as 150 ppm or 180 ppm, or it can be a percentage value, such as 5% or 8%.

[0087] If the reading of any gas sensor fluctuates more than the first target amplitude, the wind speed of each fan 130 can be reduced by adjusting each wind speed regulator 140 to weaken the airflow disturbance intensity and make the gas flow more stable.

[0088] In this embodiment, by reducing the fan speed when the gas sensor reading fluctuates significantly, the intensity of the airflow can be weakened, the gas concentration around the sensor can be stabilized, the interference of the airflow on the sensor can be reduced, and the accuracy of the gas sensor test can be further improved.

[0089] In some embodiments, the gas injection assembly 150 includes an injection device 151, a first conduit 152, and a second conduit 153; The injection device 151 is connected to the gas source 160 through the first pipeline 152 and to the sealed chamber 110 through the second pipeline 153.

[0090] In this embodiment, the first pipeline 152 is connected to both the injection device 151 and the gas source 160, and can deliver the high-pressure or normal-pressure test gas stored in the gas source 160 to the injection device 151. The first pipeline 152 can be configured with auxiliary components such as pressure reducing valves, filters, and dryers as needed.

[0091] The second pipeline 153 is connected to both the injection device 151 and the sealed chamber 110, and can deliver the test gas in the injection device 151 to the sealed chamber 110. The outlet of the second pipeline 153 is connected to the sealed chamber 110, and the outlet can be set on the air inlet side of the fan 130 or at the beginning of the airflow circulation path, so that the injected test gas can be quickly dispersed into the chamber space under the action of the airflow generated by the fan 130.

[0092] The injection device 151 can draw test gas from the gas source 160 through the first pipeline 152 and inject the test gas into the sealed chamber 110 through the second pipeline 153. The injection device 151 can be a syringe, injection pump, piston metering pump, or volumetric gas distributor, etc., and this application embodiment does not limit it.

[0093] In this embodiment, the injection device is connected to the gas source 160 through the first pipeline to obtain the test gas, and the injection device is connected to the sealed chamber through the second pipeline to inject a quantitative amount of test gas into the chamber. This realizes the separation of the gas acquisition and injection process, and improves the accuracy and safety of the test gas delivery.

[0094] In some embodiments, the gas injection assembly 150 further includes a gas pipe connector 154, a first switch assembly 155 disposed in the first pipeline 152, and a second switch assembly 156 disposed in the second pipeline 153; The injection device 151 is connected to the first pipeline 152 and the second pipeline 153 via the endotracheal connector 154.

[0095] In this embodiment, the endotracheal connector 154 serves as the external interface of the injection device 151, enabling the injection device 151 to connect to the first conduit 152 and the second conduit 153 via a single connector. The endotracheal connector 154 can be a tee connector, a quick-connect connector, or an integrated multi-port valve block, etc.

[0096] In some embodiments, the endotracheal connector 154 adopts a three-way structure, including a main interface connected to the outlet end of the injection device 151, and two branch interfaces respectively connected to the first conduit 152 and the second conduit 153. The main interface and the outlet end of the injection device 151 can be sealed and fixed by means of threaded connection, compression fitting connection or quick-connect connection, etc., and the two branch interfaces are respectively connected to the corresponding ends of the first conduit 152 and the second conduit 153 through conduit connectors.

[0097] The first switch assembly 155 is disposed on the first pipeline 152 and is used to control the air flow of the first pipeline 152; the second switch assembly 156 is disposed on the second pipeline 153 and is used to control the air flow of the second pipeline 153. The first switch assembly 155 and the second switch assembly 156 may use the same or different types of switching elements, such as solenoid valves, pneumatic valves, manual ball valves, needle valves, snap-fit ​​valves, etc.

[0098] In this embodiment, the injection device is connected to the first pipeline and the second pipeline respectively through the air pipe connector, and a first switch assembly is set in the first pipeline and a second switch assembly is set in the second pipeline. This allows for independent control of the gas supply on the gas source side and the gas injection on the chamber side, thereby improving the accuracy of the test gas injection volume control and the convenience of the test operation.

[0099] In some embodiments, injecting a target volume of test gas into the sealed chamber 110 via the gas injection assembly 150 includes: Open the valve of the gas source 160 and open the first switch assembly 155. Draw the test gas through the injection device 151 and close the first switch assembly 155 when the test gas in the injection device 151 reaches the target volume. Turn on the second switch assembly 156, inject test gas into the sealed chamber 110 through the injection device 151, and turn off the second switch assembly 156 after injecting the target volume of test gas.

[0100] Step 610: Open the valve of the gas source 160 and turn on the first switch assembly 155 to establish a gas path from the gas source 160 to the injection device 151.

[0101] In this embodiment, during the test gas injection phase, the valve of the gas source 160 can first be opened to make the test gas in the gas source 160 available for output, and the first switch assembly 155 is controlled to switch to the open state, so that the first pipeline 152 forms a smooth gas passage. The second switch assembly 156 remains in the closed state, and the second pipeline 153 is in the blocked state.

[0102] After the gas path from gas source 160 to injection device 151 is established, due to the closure of the second switch assembly 156, the test gas is confined to the gas path section between gas pipe connector 154 and first switch assembly 155 and will not flow to the second pipeline 153 or sealed chamber 110.

[0103] The injection device 151 can be activated to extract test gas. Taking the injection device 151 as a piston-type structure as an example, the piston can be controlled to move backward at a preset speed inside the injection cylinder, forming a gradually increasing negative pressure chamber at the front end of the injection cylinder. Under the action of pressure difference, the test gas flows into the injection cylinder from the gas pipe connector 154, filling the negative pressure chamber. During the extraction process, the volume of test gas inside the injection device 151 is monitored by detection elements such as displacement sensors, encoders, or flow meters built into the injection device 151, or by the scale of the injection device 151. When the volume of test gas reaches the preset target volume, the piston of the injection device 151 is kept in its current position, forming a fixed-volume metered gas chamber inside the injection cylinder. The first switch assembly 155 is then switched to the closed state, cutting off the gas passage of the first pipeline 152, thus physically isolating the gas source 160 from the injection device 151.

[0104] In this embodiment, after the test gas extraction is completed and the first switch assembly 155 is turned off, the second switch assembly 156 can be controlled to switch to the open state, so that the second pipeline 153 forms a smooth gas passage.

[0105] After the gas path from the injection device 151 to the sealed chamber 110 is established, the test gas can only flow unidirectionally along the second pipeline 153 because the first switch assembly 155 is closed. The injection device 151 can be activated to inject the test gas, i.e., the piston is controlled to move forward at a preset speed, pushing the test gas stored in the injection cylinder out. The test gas flows sequentially through the gas pipe connector 154 and the second pipeline 153, entering the sealed chamber 110 through the outlet. When the volume of injected test gas reaches the target volume, the second switch assembly 156 is switched to the closed state, cutting off the gas path of the second pipeline 153, thus creating physical isolation between the injection device 151 and the sealed chamber 110, reducing the interference of mechanical vibration or temperature changes of the injection device 151 on the internal environment of the chamber.

[0106] In this embodiment, by first opening the gas source valve and the first switch assembly, the test gas is extracted from the gas source using the injection device, and the first switch assembly is closed when the test gas in the injection device reaches the target volume. By opening the second switch assembly, the test gas in the injection device is injected into the sealed chamber, and the second switch assembly is closed after the injection is completed. This allows for accurate control of the volume of the extracted test gas and the volume of the injected test gas.

[0107] In some embodiments, the method further includes: The performance of each gas sensor is evaluated based on its alarm response time, target reading value when the reading is stable, and the time to reach a preset percentage of the target reading value.

[0108] In this embodiment, the alarm response time of each gas sensor can be compared with a preset response time standard value to evaluate the dynamic response sensitivity of the gas sensor. For example, if the alarm response time is greater than the response time standard value, the dynamic response sensitivity of the gas sensor is determined to be unqualified; if the alarm response time is less than or equal to the response time standard value, the dynamic response sensitivity of the gas sensor is determined to be qualified. Alternatively, a score can be determined for each gas sensor on the dynamic response sensitivity item based on the comparison results. For example, if the alarm response time is greater than the response time standard value, the dynamic response sensitivity of the gas sensor is determined to be unqualified with a score of 0; if the alarm response time is less than or equal to the response time standard value, the dynamic response sensitivity of the gas sensor is determined to be qualified. The shorter the alarm response time, the higher the score.

[0109] The measurement accuracy of each gas sensor can be evaluated by comparing the target reading with the theoretical concentration value. Specifically, the theoretical concentration of the test gas can be calculated based on the target volume of the injected test gas and the volume of the sealed chamber 110. The closer the target reading is to the theoretical concentration value, the higher the measurement accuracy. Alternatively, the individual score for each gas sensor in the test accuracy category can be determined based on the comparison results; for example, the closer the target reading is to the theoretical concentration value, the higher the score.

[0110] Taking a preset ratio of T90 as an example, the T90 time of each gas sensor can be compared with a preset T90 standard value to evaluate the dynamic response speed of each gas sensor. The preset T90 standard value can be a standard value based on sensor technical specifications and industry application requirements. For example, for an electrochemical carbon monoxide sensor, the T90 standard value can be set to 45 seconds; for a semiconductor methane sensor, the T90 standard value can be set to 30 seconds. If the T90 time of a gas sensor is greater than the preset T90 standard value, the dynamic response speed of the gas sensor is determined to be unqualified; if the T90 time is less than or equal to the preset T90 standard value, the dynamic response speed of the gas sensor is determined to be qualified. Alternatively, a score can be determined for each gas sensor in the dynamic response speed category based on the comparison results. For example, if the T90 time is greater than the preset T90 standard value, the dynamic response speed of the gas sensor is determined to be unqualified with a score of 0; if the T90 time is less than or equal to the preset T90 standard value, the dynamic response speed of the gas sensor is determined to be qualified. The smaller the T90 time, the higher the score.

[0111] In some embodiments, the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach a preset percentage of the target reading value can be combined to comprehensively evaluate each gas sensor. For example, weighting coefficients can be set for the alarm response time, the target reading value when the reading is stable, and the time to reach a preset percentage of the target reading value for each gas sensor. After calculating the scores for each evaluation, a comprehensive score is calculated by weighted summation. The performance of the gas sensor is evaluated based on the comprehensive score. For example, based on the comprehensive score, the performance of the gas sensor can be divided into excellent, good, qualified, and unqualified levels.

[0112] In this embodiment, by correlating the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach the preset proportion of the target reading value, the requirements of gas sensors on response speed, measurement accuracy, and stability in actual application scenarios are fully considered, thereby improving the accuracy of gas sensor performance evaluation.

[0113] It should be noted that, in this document, 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 that element. Furthermore, it should be noted that the scope of the methods and apparatuses in the embodiments of this application is not limited to performing functions in the order shown or discussed, but may also include performing functions substantially simultaneously or in the reverse order, depending on the functions involved. For example, the described methods may be performed in a different order than described, and various steps may be added, omitted, or combined. Additionally, features described with reference to certain examples may be combined in other examples.

[0114] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a computer software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) and includes several instructions to cause a terminal (which may be a mobile phone, computer, server, or network device, etc.) to execute the methods described in the various embodiments of this application.

[0115] The embodiments of this application have been described above with reference to the accompanying drawings. However, this application is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of this application without departing from the spirit and scope of the claims, and all of these forms are within the protection scope of this application.

[0116] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "illustrative embodiment," "example," "specific example," or "some examples," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0117] Although embodiments of this application have been shown and described, those skilled in the art will understand that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of this application, the scope of which is defined by the claims and their equivalents.

Claims

1. A testing method for a gas sensor, characterized in that, The method is applied to a testing device, which includes: a sealed chamber with multiple mounting positions for fixing gas sensors and multiple fans; each fan has a corresponding wind speed regulator; and a gas injection assembly connected to the sealed chamber for injecting test gas into the sealed chamber. Each of the aforementioned wind speed regulators adjusts each of the aforementioned wind turbines to the target wind speed, thereby enabling each of the aforementioned wind turbines to operate for the target duration; With each of the aforementioned fans running, a target volume of test gas is injected into the sealed chamber through the gas injection assembly; Once the test gas injection is complete, adjust the wind speed of each fan according to the readings of each gas sensor in the sealed chamber, and record the alarm response time of each gas sensor, the target reading value when the reading is stable, and the time to reach the preset proportion of the target reading value.

2. The method according to claim 1, characterized in that, The step of adjusting the wind speed of each fan based on the readings of each gas sensor inside the sealed chamber includes: If the difference between the readings of any two gas sensors is greater than the target threshold, the wind speed of each of the fans is increased by each of the wind speed regulators.

3. The method according to claim 1, characterized in that, The step of adjusting the wind speed of each fan based on the readings of each gas sensor inside the sealed chamber includes: If the reading fluctuation of any of the gas sensors exceeds the first target amplitude, the wind speed of each of the fans is reduced by each of the wind speed regulators.

4. The method according to claim 1, characterized in that, The gas injection assembly includes an injection device, a first pipeline, and a second pipeline; The injection device is connected to the gas source through the first pipeline and to the sealed chamber through the second pipeline.

5. The method according to claim 4, characterized in that, The gas injection assembly further includes a gas pipe connector, a first switch assembly disposed in the first pipeline, and a second switch assembly disposed in the second pipeline; The injection device is connected to the first pipeline and the second pipeline respectively through the endotracheal connector.

6. The method according to claim 5, characterized in that, The injection of a target volume of test gas into the sealed chamber via the gas injection assembly includes: Open the valve of the gas source and turn on the first switch assembly to draw the test gas through the injection device. When the test gas in the injection device reaches the target volume, turn off the first switch assembly. The second switch assembly is turned on, and the test gas is injected into the sealed chamber through the injection device. After injecting the target volume of test gas, the second switch assembly is turned off.

7. The method according to claim 1, characterized in that, The method further includes: The performance of each gas sensor is evaluated based on its alarm response time, the target reading value when the reading is stable, and the time required to reach a preset percentage of the target reading value.

8. The method according to claim 1, characterized in that, The number of fans is two, and the two fans are symmetrically arranged on the inner wall of the sealed chamber.

9. The method according to claim 1, characterized in that, Each of the aforementioned wind speed regulators includes multiple wind speed settings, with different wind speed settings corresponding to different wind speeds of the fan.

10. A testing device for a gas sensor, characterized in that, include: The sealed chamber has multiple mounting positions for fixing gas sensors and multiple fans inside; each fan is equipped with a wind speed regulator. A gas injection assembly, connected to the sealed chamber, is used to inject test gas into the sealed chamber; A controller for performing the method as described in any one of claims 1-9.

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