System and method for automatically detecting response time of gas sensor

Abstract

The invention discloses a gas sensor response time automatic detection system and method, and the system comprises a standard gas source, a switching valve module, a pressure control module, gas drainage equipment, and a sealing device for packaging a controlled sensor. One end of the pressure control module is connected with the gas drainage equipment and is connected with the standard gas source through the switch valve module, the other end of the pressure control module is connected with the sealing device, and the main control module is respectively connected with the switch valve module, the pressure control module and the sealing device; the main control module sets the pressure value in the sealing device by controlling the on-off of the switch valve module and the gas drainage equipment and controlling the pressure control module so as to regulate and control the pressure state in the sealing device, and calculates the response time of the sensor according to the output data of the tested sensor. The method has the advantages of being easy to implement and operate, low in cost, high in detection efficiency and precision, high in flexibility and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of gas sensors, and in particular, to a system and method for automatically detecting the response time of a gas sensor. Background Art

[0002] Gas sensors can monitor the gas concentration in the environment and are widely used in industrial fields such as metallurgy, electric power, petrochemical industry, automotive engine control, and food safety. The reliable measurement of gas sensors is crucial. Among them, the response time of gas sensors is a key indicator to measure the performance of gas sensors. Especially for unpredictable mutation situations in the environment, such as high temperature, vibration, low pressure, etc., the response time of the sensor will greatly affect the reliability and stability of the output. Taking the oxygen sensor as an example, the oxygen sensor is mainly installed in places with oxygen excess danger and oxygen deficiency danger to detect the oxygen content in the environment. As an important gas required for life, the oxygen concentration value directly affects production safety and personal safety. Therefore, the oxygen sensor must have a sufficient response speed to give an alarm in time when the external environment changes suddenly and reduce damage.

[0003] During the long-term use of the sensor, the responsiveness will gradually slow down, resulting in a certain lag in the sensor test data. Therefore, in order to improve the accuracy and reliability of the test, it is necessary to regularly perform maintenance tests on the sensor to compensate for the deviation caused by parameters such as the response time of the sensor. At present, the gas sensor response time measurement device usually changes the gas concentration by manually adjusting the gas sensor multiple times, and then performs data interpretation, changes the external environment, records the sensor test data, and analyzes the data change situation to obtain the sensor response time. This type of manual operation method will have certain human errors, and it is impossible to accurately read the sensor response time, which will in turn affect the precise adjustment of the response time correction amount.

[0004] Some practitioners have proposed to set up a test gas path for the gas sensor, provide standard gas or ambient air to the gas sensor through the test gas path according to the control instruction, and then sense the gas concentration in real time to obtain the response time of the gas sensor, so as to realize the automatic detection of the response time of the gas sensor. Although the above method can achieve the automation of sensor response time detection to a certain extent, the air supply method through the test gas path will reduce the airtightness. At the same time, considering the residual gas in the gas pipe and the gas flow rate, certain deviations will be introduced. When the control instruction is issued, it cannot be guaranteed that the response time detected by the sensor is the response time of the sensor itself, resulting in inaccurate measurement results. Summary of the Invention

[0005] The technical problem to be solved by the present invention lies in: aiming at the technical problems existing in the prior art, the present invention provides an automatic detection system and method for the response time of a gas sensor, which are simple to operate, low in cost, high in detection efficiency and accuracy, and strong in flexibility.

[0006] To solve the above technical problems, the technical solution proposed by the present invention is:

[0007] An automatic detection system for the response time of a gas sensor, comprising: a standard gas source, a switching valve module, a pressure control module, a gas pumping device, and a sealing device for encapsulating the sensor to be controlled. One end of the pressure control module is connected to the gas pumping device and connected to the standard gas source through the switching valve module, and the other end is connected to the sealing device. The system further comprises a main control module respectively connected to the switching valve module, the pressure control module, and the sealing device. The main control module controls the opening and closing of the switching valve module and the gas pumping device, and controls the pressure control module to set the pressure value in the sealing device, so as to regulate the pressure state in the sealing device, and calculates the sensor response time according to the output data of the sensor to be measured.

[0008] Further, the main control module includes a valve control unit, a pressure setting unit, and a response time calculation unit. The valve control unit is used to control the opening and closing of the switching valve module. The pressure setting unit is used to send a control instruction to the pressure control module to set the pressure value in the sealing device. The response time calculation unit is used to calculate the sensor response time according to the output data of the sensor to be measured.

[0009] Further, when the switching valve module is opened to introduce standard gas into the sealing device and the pressure value in the sealing device is stably maintained at a preset pressure value, the time when the difference between the output value of the sensor to be measured and the reference initial value reaches a preset ratio of the reference difference is obtained by the response time calculation unit and output as the detected sensor response time. The reference difference is the difference between the reference final value and the reference initial value.

[0010] Further, the reference final value is the output value of the sensor to be measured when the switching valve module is controlled to be opened to introduce standard gas into the sealing device in an approximately vacuum state in the sealing device, and the pressure in the sealing device is controlled to be maintained at the preset pressure value by the pressure control module. The reference initial value is the output value of the sensor to be measured when the switching valve module is closed, the sealing device is evacuated, and the pressure in the sealing device is controlled to reach an approximately vacuum state by the pressure control module.

[0011] Further, the switching valve module is an electromagnetic valve, and the gas pumping device is a gas pump.

[0012] An automatic detection method for the response time of a gas sensor, the steps including:

[0013] Step S01. Perform a pumping operation on the sealing device encapsulating the controlled sensor so that the pressure inside the sealing device is maintained at a first pressure value; perform a vacuum pumping operation on the sealing device until the pressure inside the sealing device is stable in an approximately vacuum state;

[0014] Step S02. Introduce a standard gas into the sealing device and maintain the pressure inside the sealing device at a second pressure value. When the output of the sensor under test reaches a stable state, obtain the output value of the sensor under test and use it as the reference final value;

[0015] Step S03. Stop introducing the standard gas into the sealing device to maintain the pressure inside the sealing device at the first pressure value; perform a vacuum pumping operation on the sealing device until the pressure inside the sealing device is re-stable in an approximately vacuum state, and obtain the current output value of the sensor under test and use it as the reference initial value;

[0016] Step S04. Control the introduction of the standard gas into the sealing device, record the starting time of introducing the standard gas into the sealing device, and keep introducing the standard gas into the sealing device so that the pressure inside the sealing device is maintained at the second pressure value;

[0017] Step S05. Scan and obtain the output value of the controlled sensor at a specified step size and calculate the difference from the reference initial value, and judge whether the magnitude relationship between the calculated difference and the reference difference satisfies a preset condition. If so, obtain the current time and output it as the detected sensor response time. The reference difference is the difference between the reference initial value and the reference final value.

[0018] Further, the sealing device is respectively connected to a standard gas source and a gas pumping and discharging device through a pressure control module. A switching valve module is arranged between the pressure control module and the standard gas source. In steps S01 to S04, by controlling the switching of the switching valve module and the gas pumping and discharging device and controlling the pressure control module, the pressure value inside the sealing device is set to regulate the pressure state inside the sealing device.

[0019] Further, in step S05, if it is judged that the currently calculated difference reaches a preset proportion of the reference difference, obtain the current time and output it as the detected sensor response time.

[0020] Further, in step S05, it also includes judging whether the output value of the sensor under test continuously increases within a plurality of consecutive step sizes. If so, perform the operation of obtaining the output value of the controlled sensor and calculating the difference from the reference initial value, otherwise return to step S01 to perform the detection again.

[0021] Further, after step S05, it further includes determining whether the detected sensor response time is within a preset threshold range. If it is, it is determined that the sensor responsiveness requirement is met; otherwise, it is determined that the sensor responsiveness requirement is not met.

[0022] Compared with the prior art, the advantages of the present invention are as follows:

[0023] 1. In the present invention, by encapsulating the controlled sensor in a sealed device, an adjustable gas channel is formed by a standard gas source, a switching valve module, a pressure control module, and a gas extraction device. Combining the switching of the switching valve module and the gas extraction device, the gas extraction and discharge operations in the sealed device are realized. At the same time, the pressure value in the sealed device is controlled by the pressure control module, which can flexibly adjust the gas chamber environment where the controlled sensor is located and the pressure state in the sealed device, ensure airtightness, and conveniently make only the standard gas remain in the sealed device, avoid introducing residual gas in the gas pipe, and reduce the influence of gas flow rate, thereby reducing detection errors, improving the accuracy of sensor response time detection, and realizing automatic and accurate detection of the gas sensor response time.

[0024] 2. The present invention further performs two vacuum pumping operations on the sealed device before detection, which can improve the purity of the gas in the sealed device, ensure the purity of the gas in the environment around the sensor. At the same time, by combining the method of pumping and discharging standard gas multiple times to change the environmental pressure and adjusting the pressure value inside the sealed device for response time detection, it can not only consider the sensor response under normal conditions, but also detect the sensor response under different pressures, thereby ensuring the accuracy of the response detection time. At the same time, by combining the reference initial value and the final value to determine the reference difference, the system error of the external channels of the sensor such as the gas pipeline can be effectively offset by using the difference operation, thereby further improving the detection accuracy and reliability of the response time. Description of the Drawings

[0025] Figure 1 is a schematic structural diagram of the automatic detection system for the gas sensor response time in this embodiment.

[0026] Figure 2 is a schematic structural diagram of the main control module in this embodiment.

[0027] Figure 3 is a schematic flowchart of realizing the automatic detection of the gas sensor response time in this embodiment.

[0028] Figure 4 is a detailed flowchart of realizing the automatic detection of the gas sensor response time in the specific application embodiment of the present invention.

[0029] Legend: 1. Standard gas source; 2. Switch valve module; 3. Pressure control module; 4. Gas extraction device; 5. Controlled sensor; 6. Sealing device; 7. Main control module; 71. Valve control unit; 72. Pressure setting unit; 73. Response time calculation unit; 74. Data storage unit. Detailed implementation mode

[0030] The present invention will be further described below in conjunction with the accompanying drawings of the specification and specific preferred embodiments, but the protection scope of the present invention is not limited thereby.

[0031] As shown in the disclosure of the present invention, unless the context clearly indicates an exceptional situation, words such as "a", "an", "one" and / or "the" do not specifically refer to the singular and may also include the plural. The words "first", "second" and similar words used in the disclosure of the present invention do not indicate any order, quantity or importance, but are only used to distinguish different components. Similarly, words such as "comprising" or "including" mean that the elements or objects appearing before the word cover the elements or objects listed after the word and their equivalents, without excluding other elements or objects. "Connection" or "connected" and similar words are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect.

[0032] As Figure 1 shown, the automatic detection system for the response time of the gas sensor in this embodiment includes: a standard gas source 1, a switch valve module 2, a pressure control module 3, a gas extraction device 4, and a sealing device 6 for encapsulating the controlled sensor 5. One end of the pressure control module 3 is connected to the gas extraction device 4 and connected to the standard gas source 1 through the switch valve module 2, and the other end is connected to the sealing device 6. It also includes a main control module 7 respectively connected to the switch valve module 2, the pressure control module 3, and the sealing device 6. The main control module 7 controls the opening and closing of the switch valve module 2 and the gas extraction device 4 and controls the pressure control module 3 to set the pressure value in the sealing device 6 to regulate the pressure state in the sealing device 6, and calculates the sensor response time according to the output data of the measured sensor.

[0033] In this embodiment, the controlled sensor 5 is encapsulated in a sealing device 6, and a standard gas source 1, a switching valve module 2, a pressure control module 3, and a gas extraction device 4 form an adjustable gas channel. By combining the switching of the switching valve module 2 and the gas extraction device 4, the gas extraction and discharge operations in the sealing device 6 are realized. At the same time, the pressure value in the sealing device 6 is controlled by the pressure control module 3, which can flexibly adjust the gas chamber environment where the controlled sensor is located and the pressure state in the sealing device 6. It can ensure airtightness while conveniently leaving only the standard gas in the sealing device 6, avoiding introducing residual gas in the gas pipe and reducing the influence of gas flow rate, thereby reducing detection errors and improving the accuracy of detecting the sensor response time, and realizing automatic and accurate detection of the gas sensor response time.

[0034] Optionally, the standard gas source 1 is a gas cylinder with a certain concentration. A sensor placement bracket is provided in the sealing device 6 to enable the sensor to be placed vertically, ensuring that the sensor gas chamber cavity is not blocked. The outer shell of the sealing device 6 is provided with an electrical connection port and a gas pipe connection port, which are respectively connected to the main control module 7 and the pressure control module 3.

[0035] As Figure 2 shown, in this embodiment, the main control module 7 specifically includes a valve control unit 71, a pressure setting unit 72, and a response time calculation unit 73. The valve control unit 71 is connected to the switching valve module 2 to control the switching of the switching valve module 2 by sending switching instructions and control the introduction of standard gas into the sealing device 6. The pressure setting unit 72 is connected to the pressure control module 3 to send control instructions to the pressure control module 3 to set the pressure value in the sealing device 6, thereby realizing the regulation of the pressure state in the sealing device 6. The response time calculation unit 73 is connected to the valve control unit 71 to calculate the sensor response time according to the output data of the measured sensor.

[0036] The time required for the sensor signal to rise from zero to a certain percentage of the ventilation equilibrium point is the sensor response time, and the response time can be used to evaluate the reaction speed of a system to an input signal. In this embodiment, when the switching valve module 2 is opened to introduce standard gas into the sealing device 6 and the pressure value in the sealing device 6 is stably maintained at a preset pressure value, the time when the difference between the output value of the measured sensor and the reference initial value reaches a preset ratio of the reference difference is obtained by the response time calculation unit 73 and output as the detected sensor response time. The reference difference is the difference between the reference final value and the reference initial value. By comparing the difference between the output value of the real-time measured sensor and the reference initial value with the reference difference, the response time calculation unit 73 can facilitate the elimination of systematic errors in the external channels of the sensor such as gas pipelines, thereby accurately and efficiently determining the response time of the sensor.

[0037] Optionally, the reference final value can specifically be obtained by controlling the opening of the switch valve module 2 to introduce a standard gas into the sealing device 6 when an approximate vacuum state is achieved within the sealing device 6, and controlling the pressure within the sealing device 6 to be maintained at a preset pressure value by the pressure control module 3, and taking the output value of the sensor under test at this time as the reference final value. The reference initial value can be obtained by closing the switch valve module 2, performing a vacuum pumping operation on the sealing device 6, and controlling the pressure within the sealing device 6 to reach an approximate vacuum state by the pressure control module 3, and taking the output value of the sensor under test at this time as the reference initial value. The reference initial value and final value determined in the above manner include the systematic errors of the external channels of the sensor such as the gas pipeline. Therefore, the error can be cancelled by difference operation, thereby effectively improving the detection accuracy of the response time.

[0038] Optionally, the main control module 7 is further provided with a data storage unit 74 for storing the output data of the sensor during the detection process and the like. The data storage unit 74 is connected to the response time calculation unit 73. During the detection process, the data storage unit 74 provides the stored continuous output data of the sensor to the response time calculation unit 73, and the response time result is calculated.

[0039] Preferably, the switch valve module 2 can adopt a two-way solenoid valve, and the gas extraction device 4 can adopt an air pump. A two-way gas channel is formed by combining the two-way solenoid valve and the air pump, and the air chamber environment is changed by the way of pumping gas by the air pump, so that only the standard gas remains in the sealing device. The pressure control module 3 is respectively connected to the air pump and the solenoid valve. According to the setting of the main control module 7, the pressure regulation of the standard gas in the sealing device 6 is realized by controlling the opening and closing of the electromagnetic valve and the air pump. It can be understood that the switch valve module 2 can of course also adopt other types of switch valve components according to actual needs, such as electric butterfly valves, gate valves, knife gate valves, etc., and the gas extraction device 4 can also adopt other types of gas extraction equipment such as air compressors, vacuum pumps, etc.

[0040] As Figure 3 shown, the steps of the method for automatically detecting the response time of the gas sensor in this embodiment include:

[0041] Step S01. Vacuum pumping of the sealing device: Perform a gas pumping operation on the sealing device 6 encapsulating the sensor under control 5 to maintain the pressure within the sealing device 6 at a first pressure value; perform a vacuum pumping operation on the sealing device 6 until the pressure within the sealing device 6 stabilizes at an approximate vacuum state;

[0042] Step S02. First introduction of the standard gas: Introduce the standard gas into the sealing device 6 and maintain the pressure within the sealing device 6 at a second pressure value. When the output of the sensor under test reaches a stable state, obtain the output value of the sensor under test and use it as the reference final value;

[0043] Step S03. Vacuum pumping for the sealing device: Stop introducing the standard gas into the sealing device 6 to maintain the pressure inside the sealing device 6 at the first pressure value; perform a vacuum pumping operation on the sealing device 6 until the pressure inside the sealing device 6 stabilizes again at an approximately vacuum state, and obtain the output value of the current sensor under test as the reference initial value;

[0044] Step S04. Second introduction of standard gas: Control the introduction of the standard gas into the sealing device 6, record the starting time of introducing the standard gas into the sealing device 6, and keep introducing the standard gas into the sealing device 6 to maintain the pressure inside the sealing device 6 at the second pressure value;

[0045] Step S05. Response time calculation: Scan and obtain the output value of the controlled sensor 5 at a specified step size and calculate the difference from the reference initial value, and determine whether the magnitude relationship between the calculated difference and the reference difference meets the preset condition. If so, obtain the current time and output it as the detected sensor response time. The reference difference is the difference between the reference initial value and the reference final value.

[0046] In this embodiment, by performing two vacuum pumping operations on the sealing device 6 before detection, the purity of the gas inside the sealing device 6 can be improved, and the purity of the gas in the environment around the sensor can be ensured, so that only the standard gas exists during the detection process without the interference of ambient air. At the same time, by combining the method of repeatedly pumping and discharging the standard gas to change the ambient pressure and adjusting the pressure value inside the sealing device 6 for response time detection, not only can the sensor response under normal conditions be considered, but also the sensor response under different pressures can be detected, thereby ensuring the accuracy of the response detection time. At the same time, by combining the reference initial value and the final value to determine the reference difference, the system error of the external channels of the sensor such as the gas pipeline can be effectively offset by using the difference operation, thereby further improving the detection accuracy and reliability of the response time.

[0047] Take the detection system shown in Figure 1 as an example. That is, the sealing device 6 is respectively connected to the standard gas source 1 and the gas pumping and discharging device 4 through the pressure control module 3, and a switching valve module 2 is arranged between the pressure control module 3 and the standard gas source 1. In steps S01 to S04, by controlling the switches of the switching valve module 2 and the gas pumping and discharging device 4 and controlling the pressure control module 3 to set the pressure value inside the sealing device 6, the pressure state inside the regulated sealing device 6 is adjusted.

[0048] Specifically, in step S01, the gas extraction device 4 is controlled to be turned on for air extraction operation, and the switch valve module 2 is kept closed so that the pressure in the sealing device 6 is maintained at the first pressure value; in step S02, the switch valve module 2 is opened to introduce standard gas into the sealing device 6 until the pressure in the sealing device 6 is maintained at the second pressure value; in step S03, the switch valve module 2 is closed to maintain the pressure in the sealing device 6 at the first pressure value, and in step S04, the switch valve module 2 is opened to introduce standard gas into the sealing device 6 until the pressure in the sealing device 6 is maintained at the second pressure value. The above first pressure value and second pressure value can be specifically configured according to actual needs. For example, the first pressure value can be configured as 0 kPa and the second pressure value can be configured as 100 kPa. When the pressure value in the sealing device 6 is 3 kPa, it is in an approximately vacuum state.

[0049] Optionally, in step S05, if it is determined that the currently calculated difference reaches a reference difference at a preset ratio, the current time is obtained as the detected sensor response time output. Considering that the sensor response time is the time when the sensor signal rises from zero to a certain percentage of the ventilation equilibrium point. For example, if it takes 10 s for a gas detector to change from a reading of 0 to 90% of the gas concentration measured in the environment, then the response time of this detector is 10 s. Preferably, the above preset ratio can be taken as 90%, that is, if the difference between the currently calculated output value of the sensor and the reference initial value reaches 90% of the reference difference, it indicates that the sensor output signal has reached the response time, and the current time is taken as the response time of the sensor.

[0050] Furthermore, the data during the detection process can be completely saved, recording the initial value and final value of the gas sensor, so as to further improve the subsequent algorithm processing speed and the accuracy of response time discrimination.

[0051] Optionally, in step S05, it also includes determining whether the output value of the measured sensor continuously increases within a continuous plurality of step lengths. If so, the output value of the controlled sensor 5 is obtained and the difference from the reference initial value is calculated. Otherwise, it indicates that the current does not meet the sensor corresponding diagnosis condition, and the process returns to step S01 for re-detection.

[0052] Optionally, after step S05, it also includes determining whether the detected sensor response time is within a preset threshold range. If so, it is determined that the sensor response requirement is met, otherwise it is determined that the sensor response requirement is not met, and it can be further determined whether the sensor meets the response requirement. For example, if the detected sensor response time is less than the preset response time threshold, it is determined that the current sensor meets the sensor response requirement, otherwise it is determined that it does not meet the requirement.

[0053] Taking the oxygen sensor as an example, asFigure 4 As shown in the figure, the detailed steps for implementing the automatic detection of the response time by using the above method of the present invention in a specific application example are as follows:

[0054] Step S1: Construct a detection system as shown in Figure 1 the figure. Among them, the switching valve module 2 uses a two-way solenoid valve, and the gas extraction device 4 uses an air pump. Input the response time threshold t max . Turn on the air pump to extract air, keep the solenoid valve closed, and let the pressure control module maintain the system pressure at 0 kPa. Vacuum the sealing device 6 and wait for the pressure controller to stabilize below 3 kPa so that the sealing device 6 reaches an approximately vacuum state.

[0055] Step S2: The main control module 7 issues an instruction to control the opening of the solenoid valve, introduce standard gas into the sealing device 6, and let the pressure control module 3 maintain the system pressure at 100 kPa. After the output is stable, record the output value U of the sensor at this time 1 and use it as the reference final value.

[0056] Step S3: The main control module 7 issues an instruction to control the closing of the solenoid valve, let the pressure control module 3 maintain the system pressure at 0 kPa, vacuum the sealing device 6, and wait for the pressure controller to stabilize below 3 kPa. Record the output voltage value U of the sensor 0 and use it as the reference initial value.

[0057] Step S4: The main control module 7 issues an instruction to control the opening of the solenoid valve. Record the time when the solenoid valve is opened, that is, the time when the standard gas supplies gas to the sealing device, as t 0 . Introduce standard gas into the sealing device 6, let the pressure control module 3 maintain the system pressure at 100 kPa, and the sensor output gradually increases. Scan and record the output value U of the sensor in real time with a step size of k.

[0058] Step S5: Calculate U 差 =U - U 0 . Record the time point at this time as t 差 . If U 差 ≥(U 1 -U 0 )*90%, it indicates that the sensor output signal has reached the response time T 90 . Then the current time t 差 is the response time of the sensor. Store (U 差 , t 差 ) into the array A.

[0059] Step S6: Judge the response time t of the detected sensor 差 . If t 差 <t max, indicating that the time when the sensor detects the change in gas concentration is faster than the threshold time, it is determined that the responsiveness of the sensor meets the requirements.

[0060] The present invention can be applied to various types of gas sensors such as oxygen sensors to achieve automatic detection of the response time. On the basis of the above method, it is also possible to synchronously detect the response times of two or more gas sensors by increasing the channels of the switching valve module and the gas extraction equipment according to actual needs.

[0061] The above are only the preferred embodiments of the present invention and do not impose any form of limitation on the present invention. Although the present invention has been disclosed above with the preferred embodiments, it is not intended to limit the present invention. Therefore, any simple modifications, equivalent changes, and decorations made to the above embodiments based on the technical essence of the present invention without departing from the technical solution of the present invention shall fall within the scope of protection of the technical solution of the present invention.

Claims

1. A gas sensor response time automatic detection system, characterized in that include: A standard gas source (1), a switch valve module (2), a pressure control module (3), a gas extraction device (4) and a sealing device (6) for encapsulating a controlled sensor (5), wherein one end of the pressure control module (3) is connected to the gas extraction device (4) and to the standard gas source (1) via the switch valve module (2), and the other end is connected to the sealing device (6), and further comprises a main control module (7) connected to the switch valve module (2), the pressure control module (3) and the sealing device (6) respectively, wherein the main control module (7) controls the switch valve module (2) and the gas extraction device (4) and controls the pressure control module (3) to set the pressure value in the sealing device (6) so as to adjust the pressure state in the sealing device (6), and calculates the sensor response time according to the output data of the sensor to be tested.

2. The gas sensor response time automatic detection system according to claim 1, characterized in that: The main control module (7) comprises a valve control unit (71), a pressure setting unit (72), a response time calculation unit (73) and a data storage unit (74); the valve control unit (71) and the data storage unit (74) are respectively connected to the response time calculation unit (73); the valve control unit (71) is used to control the switch of the switch valve module (2); the pressure setting unit (72) is used to send a control instruction to the pressure control module (3) to set the pressure value in the sealing device (6); the response time calculation unit (73) is used to calculate the sensor response time according to the output data of the sensor under test; and the data storage unit (74) is used to store the output data of the sensor under test and the detection result.

3. The gas sensor response time automatic detection system according to claim 2, characterized in that: When the switch valve module (2) is opened to pass standard gas into the sealing device (6) and the pressure value in the sealing device (6) is stably maintained at a preset pressure value, the time when the difference between the output value of the sensor under test and the reference initial value reaches a preset ratio of the reference difference is obtained by the response time calculation unit (73) and output as the detected sensor response time, wherein the reference difference is the difference between the reference final value and the reference initial value.

4. The gas sensor response time automatic detection system according to claim 3, characterized in that: The reference final value is the output value of the sensor under test when the switch valve module (2) is controlled to open when a vacuum state is reached in the sealing device (6) so as to introduce standard gas into the sealing device (6), and the pressure in the sealing device (6) is controlled by the pressure control module (3) to be maintained at a preset pressure value, and the reference initial value is the output value of the sensor under test when the switch valve module (2) is closed, the sealing device (6) is evacuated, and the pressure in the sealing device (6) is controlled by the pressure control module (3) to reach a vacuum state.

5. The gas sensor response time automatic detection system according to any one of claims 1 to 4, characterized in that: The switch valve module (2) is a solenoid valve, and the gas extraction device (4) is an air pump.

6. A method for automatically detecting the response time of a gas sensor, characterized in that the steps include: Step S01. Performing a vacuum operation on a sealing device (6) encapsulating a controlled sensor (5) so that the pressure inside the sealing device (6) is maintained at a first pressure value; performing a vacuum operation on the sealing device (6) until the pressure inside the sealing device (6) is stabilized in a state close to vacuum; Step S02. introducing a standard gas into the sealing device (6) and maintaining the pressure in the sealing device (6) at a second pressure value, and obtaining the output value of the sensor under test when the output of the sensor under test reaches a stable state and using it as a reference final value; Step S03. Stop introducing the standard gas into the sealing device (6) to maintain the pressure in the sealing device (6) at the first pressure value; perform a vacuum operation on the sealing device (6) until the pressure in the sealing device (6) stabilizes at a near-vacuum state again, and obtain the output value of the current sensor under test and use it as a reference initial value; Step S04. Controlling the introduction of standard gas into the sealing device (6), recording the start time of the introduction of standard gas into the sealing device (6), and maintaining the introduction of standard gas into the sealing device (6) so that the pressure in the sealing device (6) is maintained at the second pressure value; Step S05. Scan and obtain the output value of the controlled sensor (5) according to the specified step length and calculate the difference between the output value and the reference initial value, determine whether the size relationship between the calculated difference and the reference difference meets the preset conditions, and if so, obtain the current time and output it as the detected sensor response time, and the reference difference is the difference between the reference initial value and the reference final value.

7. The method for automatically detecting the response time of a gas sensor according to claim 6, characterized in that: The sealing device (6) is respectively connected to a standard gas source (1) and a gas extraction device (4) via a pressure control module (3); a switch valve module (2) is provided between the pressure control module (3) and the standard gas source (1); in steps S01 to S04, the pressure state in the sealing device (6) is regulated by controlling the switch valve module (2) and the switch of the gas extraction device (4) and controlling the pressure control module (3) to set the pressure value in the sealing device (6).

8. The method for automatically detecting the response time of a gas sensor according to claim 6, characterized in that: In step S05, if it is determined that the currently calculated difference reaches a preset ratio of the reference difference, the current time is obtained and output as the detected sensor response time.

9. The method for automatically detecting the response time of a gas sensor according to claim 6, 7 or 8, characterized in that: Step S05 also includes determining whether the output value of the sensor under test continues to increase within a plurality of consecutive steps. If so, the output value of the controlled sensor (5) is obtained and the difference between the output value and the reference initial value is calculated. Otherwise, the process returns to step S01 for retesting.

10. The method for automatically detecting the response time of a gas sensor according to claim 6, 7 or 8, characterized in that: After step S05, it is also included to determine whether the detected sensor response time is within a preset threshold range. If so, it is determined that the sensor responsiveness requirement is met, otherwise it is determined that the sensor responsiveness requirement is not met.

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