Testing system of catalytic combustion type gas sensor

Abstract

The invention relates to a testing system of a catalytic combustion type gas sensor, and belongs to the technical field of gas sensor testing. A first diverter; the test circuit board comprises a sensor board, a plurality of tested sensor groups are arranged and installed in a matrix mode, each tested sensor group comprises a plurality of tested catalytic sensors, and the tested catalytic sensors are connected with the sensor board in an inserted mode; the first flow divider is arranged corresponding to each tested sensor group, and the gas supply mechanism uniformly injects test standard gas into the corresponding tested catalytic sensors at a low flow rate through the first flow divider; and the detection board is connected with the sensor board through a standard connector, and is used for acquiring test data of each tested catalytic sensor in each tested sensor group and uploading the test data to acquisition and analysis software built in an external PC (Personal Computer) end for analysis. The method has the beneficial effect that the testing efficiency of batch testing of the catalytic combustion type gas sensor is improved.

Description

Technical Field

[0001] The present application relates to the technical field of gas sensor testing, and in particular, to a testing system for a catalytic combustion type gas sensor. Background Art

[0002] With the popularization of gas, gas safety products have also gradually become popular, especially gas leakage alarms. The core device of a gas leakage alarm is a gas sensor, and among them, the catalytic combustion type sensor is a common gas detection sensor. A catalytic combustion sensor usually consists of a detection element and a compensation element, and has different packaging structure methods. When the sensor works, a current is passed through the detection element and the compensation element, generating high temperature. When a combustible gas contacts the catalyst on the detection element, flameless combustion will occur, causing the temperature of the carrier to rise. This temperature change will cause an increase in the platinum wire resistance in the detection element, and this change can be detected through a circuit, further realizing the measurement of the gas concentration.

[0003] To ensure the quality of gas alarms, the important technical indicators that need to be detected for catalytic combustion type sensors are: Operating current. Different operating currents generate different amounts of heat, which in turn affect the measurement results.

[0004] Zero drift, which is caused by the parameter differences between the detection element and the compensation element.

[0005] Sensitivity, which is the ratio of the gas concentration to the signal output value. Due to differences in manufacturing processes, there are differences in sensitivity between different sensors.

[0006] The response speed of the sensor is greatly affected after being exposed to environmental pollution.

[0007] For example, for a certain type of catalytic combustion type sensor, its operating current is 160 mA to 180 mA, the zero drift is ±35 mV, and the sensitivity is 17 mV to 28 mV / 10%LEL. Its technical indicators obviously have a large discreteness.

[0008] Since the response time of the catalytic sensor is relatively fast (about 3 seconds to 8 seconds), it is required that the speed of applying the test gas be fast, but the air flow speed during the test cannot be too large (not greater than 0.5 m / s); therefore, in related technologies, when testing the response speed of a catalytic sensor, the gas mixing method is usually adopted. However, since the gas mixing process is relatively slow, the test efficiency is relatively low when batch testing catalytic sensors. Summary of the Invention

[0009] In order to improve the test efficiency of batch testing of catalytic combustion type gas sensors, the present application provides a testing system for a catalytic combustion type gas sensor, and adopts the following technical solutions: A test system for a catalytic combustion type gas sensor, comprising: A gas supply mechanism; A first diverter; A test circuit board, comprising: A sensor board, on which multiple groups of sensors to be tested are arranged and installed in a matrix manner. Each group of the sensors to be tested includes a plurality of catalytic sensors to be tested, and the catalytic sensors to be tested are plugged into the sensor board; the first diverter is correspondingly arranged for each group of the sensors to be tested, and the gas supply mechanism injects the test standard gas into the corresponding group of the catalytic sensors to be tested at a low flow rate and uniformly through the first diverter; A detection board, connected to the sensor board through a standard connector, for collecting the test data of each catalytic sensor to be tested in each group of the sensors to be tested, and uploading the test data to the acquisition and analysis software built in an external PC for analysis.

[0010] By adopting the above technical solution, the catalytic sensor to be tested is plugged onto the sensor board, then the sensor board is connected to the detection board, and the working voltage of the catalytic sensor is checked to enable the catalytic sensor to go through a certain preheating time; then the data acquisition function of the detection board is started to collect the test data of the catalytic sensor in the air and upload it to the acquisition and analysis software of the PC for analysis; then the gas supply mechanism is started, and the output port of the first diverter is quickly brought close to the catalytic sensor to be tested, and the test standard gas is injected into the corresponding group of the catalytic sensors to be tested at a low flow rate and uniformly through the first diverter; the detection board collects the test data of the catalytic sensor and uploads it to the acquisition and analysis software of the PC for analysis; the corresponding data of the catalytic sensor to be tested can be calculated and generated through the acquisition and analysis software of the PC, and the response process curve can be drawn. Through the graphical curve display, the response speed between the catalytic sensors can be intuitively observed; furthermore, through data analysis, the quality classification of the catalytic sensor can be carried out; since the setting of the first diverter can ensure that the test gas reaches each catalytic sensor to be tested relatively simultaneously, ensuring the uniformity of the test gas and improving the test efficiency of the batch test of the catalytic combustion type gas sensor; In addition, on the one hand, since the application circuit of the catalytic sensor is the same, in this circuit structure mode, when catalytic sensors with different pin pitches / encapsulations need to be detected, only the sensor board needs to be replaced, without re-designing the detection board, reducing the repetition of the design and saving costs; on the other hand, since the circuit that is prone to generating heat is far away from the sensor, the influence on the sensor is minimized.

[0011] Optionally, a plurality of exhaust holes are opened around the catalytic sensor to be tested on the sensor board.

[0012] By adopting the above technical solution, the applied test standard gas is discharged to the bottom of the sensor board to prevent the test standard gas from accumulating around the catalytic sensor under test and affecting the response and output of the catalytic sensor.

[0013] Optionally, the first diverter includes: The first upper diverter body, which is hemispherical, is connected with a first inlet pipe in the middle, and the inner diameter of the first inlet pipe is 16 mm; The first lower diverter body, which is a circular plate, is detachably connected to the first upper diverter body; the first lower diverter body is uniformly connected with equidistant and equal-length first outlet pipes, the inner diameter of the first outlet pipes is 12 mm, and the first outlet pipes are arranged corresponding to the catalytic sensors under test; The cover plate is erected and fixed on the first lower diverter body for buffering the air flow entering from the first inlet pipe to ensure that the air flow is evenly dispersed into a plurality of the first outlet pipes; The first sealing ring, which is an O-ring, is used to seal the first upper diverter body and the first lower diverter body.

[0014] By adopting the above technical solution, the first outlet pipes have a certain length, which can buffer the air flow to ensure the uniformity of the air flow; the first outlet pipes of the first diverter are directly arranged corresponding to the catalytic sensors under test to ensure the shortest air flow path; due to the same length, the test gas can reach the catalytic sensors under test synchronously.

[0015] Optionally, the test system of the catalytic combustion type gas sensor further includes: The diverter rack, the first diverter is installed on the lower layer of the diverter rack, and the first inlet pipes of a plurality of the first diverters are in the same plane; The second diverter is installed on the upper layer of the diverter rack. The second diverter is provided with a plurality of output ports, and each output port is hermetically connected to the first inlet pipe of the corresponding first diverter for delivering uniform gas to a plurality of the first diverters; the diverter rack, the first diverter and the second diverter together form an air adding cover; the air adding cover can move in the direction close to or away from the sensor board; the air supply mechanism is used to supply the test standard gas to the second diverter.

[0016] By adopting the above technical solution, the test standard gas is uniformly delivered to all the catalytic sensors under test through the second diverter and the first diverter in the shortest time, reducing the time error in the operation process.

[0017] Optionally, the second diverter includes: The second upper diverter body, which is hemispherical, is connected with a second inlet pipe in the middle, and the inner diameter of the second inlet pipe is 20 mm; The second flow - dividing lower body is a circular plate and is detachably connected to the second flow - dividing upper body; the second flow - dividing lower body is uniformly communicated with equidistant and equal - length second air outlet pipes, the inner diameter of the second air outlet pipes is 16 mm, each second air outlet pipe corresponds to one of the first air inlet pipes, and the second air outlet pipes are hermetically connected to the first air inlet pipes; A cone is coaxially and fixedly connected to the circular plate and is used for uniformly dispersing the air flow input by the second air inlet pipe into a plurality of second air outlet pipes; The second sealing ring is an O - ring and is used for sealing the second flow - dividing upper body and the second flow - dividing lower body.

[0018] By adopting the above - mentioned technical solution, it is further ensured that the test standard gas is uniformly transported into a plurality of first flow - dividers.

[0019] Optionally, the gas supply mechanism includes: A plurality of standard gas cylinders are provided, which can contain standard gases with different concentrations; The intake branch pipes are correspondingly arranged with the standard gas cylinders, and one end of each intake branch pipe is communicated with the corresponding standard gas cylinder; Stop valves are connected to each intake branch pipe and are used to control the on - off of the corresponding intake branch pipe; The intake main pipe is communicated with the other ends of a plurality of intake branch pipes at one end and is hermetically connected to the second air inlet pipe of the second flow - divider at the other end; A flow meter is installed on the intake main pipe and is used to detect the flow rate of the output test standard gas.

[0020] By adopting the above - mentioned technical solution, when not in testing, all stop valves are in the cut - off state; when in testing, only one stop valve is turned on at the same time; then, according to the gas flow data collected by the flow meter, the flow velocity and flow rate of the test standard gas are adjusted to appropriate values.

[0021] Optionally, the test system of the catalytic combustion type gas sensor further includes: A counter is installed on the sensor board and is used to calculate the number of times the pin is inserted. The catalytic sensor to be tested is inserted into the sensor board in a pin - insertion manner; the counter is communicatively connected to the detection board.

[0022] By adopting the above - mentioned technical solution, each time a catalytic sensor is installed and tested on the sensor board, the counter counts once; the counter can be read by the detection board. When the number of uses reaches a specified threshold, a warning is issued to remind to replace the pin or perform maintenance testing.

[0023] Optionally, the counter adopts a rotary dial switch, and each time it is rotated, it steps one digit for counting.

[0024] By adopting the above technical solution, the sensor board can count the number of times of pin insertion without being powered on, further improving the convenience of testing.

[0025] Optionally, the following are installed on the detection board: A sensor detection group, each group corresponding to a group of the sensors to be measured, and each group includes a plurality of sensor detection modules. Each sensor detection module corresponds to one of the catalytic sensors to be measured and is used to collect the sensing data of the catalytic sensor to be measured. The sensing data includes working current, supply voltage, and sensor signal output. A microprocessor, each corresponding to a group of the sensor detection groups. Each microprocessor is communicatively connected to the corresponding sensor detection group and is used to receive the corresponding sensing data and send the test data to the acquisition and analysis software on the PC side. The test data includes the sensing data, temperature, and humidity.

[0026] In summary, the present application has at least the following beneficial effects: 1. It is possible to perform batch testing on catalytic sensors, and multiple technical indicators of the catalytic sensors can be tested, improving work efficiency and saving costs. 2. Since the application circuits of the catalytic sensors are the same, with this circuit structure, when catalytic sensors with different pin pitches / encapsulations need to be detected, only the sensor board needs to be replaced, and there is no need to redesign the detection board, reducing design repetition, and the detection board can be reused. 3. The modularization and the neat arrangement of the sensors to be measured are conducive to mechanical operation, further improving the operation efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a schematic diagram of the system structure of the present application; Figure 2 is a schematic diagram of the overall structure of the gas filling hood; Figure 3 is a schematic diagram of the structure of the first shunt; Figure 4 is a schematic diagram of the structure of the second shunt; Figure 5 is an example diagram of the sensor board; Figure 6 is a circuit diagram of the sensor detection module; Figure 7 is a principle block diagram of the detection board.

[0028] Description of reference numerals: 100, gas supply mechanism; 110, standard gas cylinder; 120, intake branch pipe; 130, stop valve; 140, intake main pipe; 150, flowmeter; 200, gas filling cover; 210, first diverter; 211, first upper diverter body; 212, first lower diverter body; 213, cover plate; 214, first sealing ring; 215, first intake pipe; 216, first outlet pipe; 220, second diverter; 221, second upper diverter body; 222, second lower diverter body; 223, cone; 224, second sealing ring; 225, second intake pipe; 226, second outlet pipe; 230, diverter rack; 300, test circuit board; 310, sensor board; 311, group of sensors to be measured; 312, catalytic sensor to be measured; 313, exhaust hole; 320, detection board. Detailed implementation manners

[0029] To make the objectives, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying Figure 1 - accompanying Figure 7 , and the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are some, but not all, of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0030] The embodiments of the present application disclose a test system for a catalytic combustion type gas sensor. Referring to Figure 1 , the test system may include a gas supply mechanism 100, a gas filling cover 200, a test circuit board 300, and acquisition and analysis software built in the PC.

[0031] Among them, a number of catalytic sensors 312 to be measured are installed on the test circuit board 300, and the gas supply mechanism 100 conveys a low-flow test standard gas to the catalytic sensors 312 to be measured through the gas filling cover 200; the test circuit board 300 uploads test data to the acquisition and analysis software in the PC, and the acquisition and analysis software calculates and generates corresponding data of the catalytic sensors 312 to be measured, and draws a response process curve. Through the graphical curve display, the response speed between the catalytic sensors can be intuitively observed; and then through data analysis, the quality classification of the catalytic sensors is carried out.

[0032] The gas filling cover 200 is movably arranged and can be driven by an external robotic arm or other driving mechanisms to move in a direction close to or away from the test circuit board 300.

[0033] The gas supply mechanism 100 includes a standard gas cylinder 110, an intake branch pipe 120, a stop valve 130, an intake main pipe 140, and a flow meter 150. Among them, there are multiple standard gas cylinders 110, which can hold standard gases with different concentrations, such as clean air, 20% LEL, 40% LEL, and 60% LEL. The standard gas cylinder 110 is equipped with a pressure reducing valve itself, which is convenient for outputting gas at an appropriate pressure; the number of standard gas cylinders 110 is set according to needs.

[0034] The number of intake branch pipes 120 is the same as that of the standard gas cylinders 110; one end of the intake branch pipe 120 is connected to the corresponding standard gas cylinder 110, and the other end is connected to one end of the intake main pipe 140; the other end of the intake main pipe 140 is connected to the gas filling cover 200, which is used to evenly inject the test standard gas at the measured catalytic sensor 312. The stop valve 130 is connected to each intake branch pipe 120 to control the on-off of the corresponding intake branch pipe 120. The flow meter 150 is installed on the intake main pipe 140 to detect the flow rate of the output test standard gas.

[0035] Refer to Figure 2 , the gas filling cover 200 may include a flow splitting frame 230, a first flow splitter 210, and a second flow splitter 220. Among them, the first flow splitter 210 is installed on the lower layer of the flow splitting frame 230, and the second flow splitter 220 is installed on the upper layer of the flow splitting frame 230. The input port of the second flow splitter 220 is connected to the other end of the intake main pipe 140, and the output port is connected to the input port of the first flow splitter 210. The output port of the first flow splitter 210 corresponds to the measured catalytic sensor 312. The second flow splitter 220 is used to evenly transport the air flow into the first flow splitter 210, and the first flow splitter 210 is used to evenly transport the air flow to the measured catalytic sensor 312.

[0036] Refer to Figure 3 , the first flow splitter 210 may include a first upper flow splitting body 211, a first lower flow splitting body 212, a cover plate 213, and a first sealing ring 214.

[0037] Among them, the first upper flow splitting body 211 is hemispherical, and a first intake pipe 215 is connected in the middle. The inner diameter of the first intake pipe 215 is 16 mm. The first lower flow splitting body 212 is a circular plate, which is detachably connected to the first upper flow splitting body 211 by screws; the first lower flow splitting body 212 is evenly connected with equidistant and equal-length first outlet pipes 216. The inner diameter of the first outlet pipes 216 is 12 mm, and the first outlet pipes 216 are arranged corresponding to the measured catalytic sensor 312. The cover plate 213 is fixedly connected to the first lower flow splitting body 212 to buffer the air flow entering from the first intake pipe 215 and ensure that the air flow is evenly dispersed into multiple first outlet pipes 216. The first sealing ring 214 is an O-ring, which is used to seal the first upper flow splitting body 211 and the first lower flow splitting body 212.

[0038] Reference Figure 4 As shown in Figure 4 , the second diverter 220 may include a second upper diverter body 221, a second lower diverter body 222, a cone 223, and a second sealing ring 224.

[0039] Among them, the second upper diverter body 221 is hemispherical, and a second intake pipe 225 is connected in the middle. The inner diameter of the second intake pipe 225 is 20 mm, and the second intake pipe 225 is hermetically connected (such as threaded connection, etc.) to the other end of the intake main pipe 140. The second lower diverter body 222 is a circular plate and is detachably connected to the second upper diverter body 221 by screws. The second lower diverter body 222 is evenly connected with equidistant and equal-length second outlet pipes 226. The inner diameter of the second outlet pipes 226 is 16 mm. Each second outlet pipe 226 corresponds to a first intake pipe 215, and the second outlet pipe 226 is hermetically connected to the corresponding first intake pipe 215. The cone 223 is coaxially and fixedly connected to the circular plate for evenly dispersing the airflow input by the second intake pipe 225 into a plurality of second outlet pipes 226. The second sealing ring 224 is an O-ring for sealing the second upper diverter body 221 and the second lower diverter body 222.

[0040] Reference Figure 5 As shown in Figure 5 , the test circuit board 300 may include a sensor board 310 and a detection board 320.

[0041] Among them, the sensor board 310 is arranged and installed with multiple groups of sensors to be measured 311 in a matrix manner. The number of the sensors to be measured 311 is the same as the number of the first diverters 210; each group of sensors to be measured 311 includes multiple catalytic sensors to be measured 312, and the number is the same as the number of the first outlet pipes 216 of the first diverter 210, and each first outlet pipe 216 is aligned with a catalytic sensor to be measured 312. In addition, a number of exhaust holes 313 are opened around the catalytic sensors to be measured 312 on the sensor board 310 to discharge the applied test standard gas to the bottom of the sensor board 310.

[0042] Furthermore, a counter is also installed on the sensor board 310. The counter is used to calculate the number of times of pin insertion. The catalytic sensors to be measured 312 are plugged into the sensor board 310 by pins. The counter is communicatively connected to the detection board 320; the sensor board 310 is connected to the detection board 320 through a standard connector. The detection board 320 can collect the test data of the catalytic sensors to be measured 312 and the count of the counter. The counter uses a rotary dial switch. Each time it rotates, it steps one count; when the sensor board 310 installs and tests a catalytic sensor each time, the counter is rotated once by a dialing tool. When the number of times of using the pins of the sensor reaches a specified threshold, the detection board 320 or the PC terminal will give a warning to remind to replace the pins or maintain the test.

[0043] The circuit diagram of the sensor detection module can be referred to Figure 6 .

[0044] Among them, DC / DC-1 is the power supply circuit that converts the input power supply into the working power supply of the catalytic sensor. The working power supply of the catalytic sensor used in this example is 2.5V.

[0045] DC / DC-2 is the power supply circuit that converts the input power supply into the working power supply of the chip. The working power supply of the chip used in this example is 3.6V.

[0046] Each group of sensors to be measured 311 uses a set of power supply circuits, that is, DC / DC-1 and DC / DC-2 respectively supply power to the circuits of multiple catalytic sensors to be measured 312. DC / DC is a general circuit and will not be described in detail.

[0047] IC1 is a high-precision AD converter, using HY3118, with 4 channels of 24-bit AD.

[0048] IC2 is a low-noise high-side current detection chip MAX4172, used to detect the working current of the catalytic sensor to be measured 312. RS is a current detection resistor, using a high-precision low-resistance resistor. The OUT terminal is the voltage output of the detected current, connected to the AD1 terminal of IC1.

[0049] CG1 is the catalytic sensor to be measured 312, C is a compensation element, D is a detection element, the two are in series, and both ends are respectively connected to the power supply and the ground. The middle point is the signal output of the sensor, connected to the AD3 terminal of IC1.

[0050] The working power supply of CG1 is connected to the AD2 terminal of IC1 through the resistor R1, and the voltage of the sensor working power supply can be detected.

[0051] The above circuit constitutes the sensor detection module circuit.

[0052] Under the control of the microprocessor in this group, IC1 detects the working current, working voltage, and output signal of the corresponding sensor, and sends the detected data information through the serial port for data analysis.

[0053] Through the working current I and the working voltage Vb, the series resistance of the compensation element and the detection element can be calculated. Through the working current I and the output voltage Va, the resistance of the detection element can be calculated, and then the resistance of the compensation element can be calculated, and then it can be judged whether the sensor is within the predetermined quality and technical requirements.

[0054] Through the voltages Va and Vb, the zero point of the sensor in clean air can be judged.

[0055] By detecting the Va voltage when applying a test gas with a predetermined concentration, the sensitivity of the sensor can be calculated, and then the sensor can be classified.

[0056] The sampling rate of HY3118 can reach 160 SPS, that is, the sampling time for each time is 6.25 ms. Each group of sensors can achieve synchronous sampling under the control of the microprocessor MCU, and then read out the detection data one by one. The reading of the sampling data of a group of sensor detection groups can be completed within 80 ms, which can meet the requirements of rapid sampling, realize the detection of the transient process of the sensor response time, and then completely draw the curve of the sensor response process, facilitating the comparison of the response curves of the sensors tested in the same batch.

[0057] Refer to Figure 7 , a sensor detection group and a microprocessor are installed on the detection board 320. Among them, the number of sensor detection groups is the same as the number of the measured sensor groups 311. Each group of sensor detection groups corresponds to a group of measured sensor groups 311. Each group of sensor detection groups includes multiple sensor detection modules, and each sensor detection module corresponds to a measured catalytic sensor 312 to collect the sensing data of the measured catalytic sensor 312. The sensing data includes working current, supply voltage, and sensor signal output.

[0058] The number of microprocessors is the same as the number of sensor detection groups. Each microprocessor corresponds to a group of sensor detection groups and is used to receive the sensing data collected by each sensor detection module in the corresponding sensor detection group. In addition, the microprocessor can also collect functions such as detection temperature, humidity, read data from the infrared analyzer, and read the rotary encoder, and send all the collected data to the PC-side acquisition and analysis software for analysis.

[0059] In other embodiments, the test circuit board 300 can be placed in a test box, and the sensor is tested using the gas distribution method to test the sensitivity of the sensor in a stable gas state and the influence of maintaining a fixed concentration for a long time on the sensitivity, which not only saves the gas source but also meets the test requirements. Multiple sets of test circuit boards 300 can also be assembled or fixed on a rack to make an aging rack for power-on aging of the sensor and monitor the relevant parameter data during the sensor aging process, such as supply current, zero drift, etc., to achieve multi-purpose use.

[0060] According to this design idea, by changing the detection circuit of the sensor, it can be used for testing sensors with other detection principles of similar shapes, such as semiconductor gas sensors, electrochemical gas sensors, thermal linear gas sensors, etc.

[0061] The implementation principle of this embodiment is: Sensor response time test: Insert the catalytic sensor 312 to be tested onto the sensor board 310, connect the sensor board 310 to the detection board 320, check the working voltage of the catalytic sensor 312 to be tested, and allow the catalytic sensor 312 to go through a certain preheating time; Connect the steel cylinder filled with standard gas to the flowmeter 150 and the gas filling hood 200 through a pipeline, open the gas cylinder pressure regulating valve, adjust the flow rate and flow to appropriate values, and evenly deliver the standard gas to each gas outlet port; Start the data acquisition function of the detection board 320. Under the control of the microprocessor, the detection board 320 collects relevant data of the catalytic sensor 312 to be tested in the air and uploads it to the acquisition and analysis software on the PC side; Then quickly bring the output port of the gas filling hood 200 close to the catalytic sensor 312 to be tested, and the standard gas in the gas cylinder is synchronously applied to the sensor of the catalytic sensor 312 to be tested. The detection board 320 continuously collects the data of the catalytic sensor 312 to be tested and uploads it to the acquisition and analysis software on the PC side. Quickly remove the gas filling hood 200, and the detection board 320 continuously collects the data of the catalytic sensor 312 to be tested and uploads it to the acquisition and analysis software on the PC side.

[0062] In this way, the output signal of the catalytic sensor 312 to be tested in the air, the sensor output signal when the standard test gas is applied, the sensor output signal when the standard gas is removed, as well as information such as the temperature and humidity at that time are collected.

[0063] According to the test requirements, the concentration of the standard gas can also be changed to obtain the gas response time at different concentrations. Different concentrations of standard gases can also be switched using a multi-channel valve switch, so that the response time at a higher concentration based on a certain concentration, or the response time from high concentration to low concentration can be obtained, realizing more performance tests on the sensor.

[0064] Through the acquisition and analysis software on the PC side, calculate and generate the corresponding data of the catalytic sensor 312 to be tested, and draw the response process curve. Through the graphical curve display, the response speed between sensors can be intuitively observed. Through data analysis, the quality of the sensors is classified.

[0065] Every time the catalytic sensor 312 to be tested is replaced, increase the count of the rotary DIP switch through the DIP tool to calculate the usage times of the sensor connector. If the usage times reach the theoretical design life, the measurement of the contact resistance should be strengthened to ensure the normal operation of the equipment.

[0066] The above are all the preferred embodiments of this application, and do not limit the protection scope of this application in turn. Any feature disclosed in this specification (including the abstract and drawings), unless specifically stated, can be replaced by other equivalent or similar-purpose alternative features. That is, unless specifically stated, each feature is only an example of a series of equivalent or similar features.

Claims

1. A test system for a catalytic combustion type gas sensor, characterized in that Including: A gas supply mechanism (100); A first diverter (210); A test circuit board (300), including: A sensor board (310) which is arranged and installed with multiple groups of sensors to be tested (311) in a matrix manner. Each group of the sensors to be tested includes multiple catalytic sensors to be tested (312). The catalytic sensors to be tested (312) are plugged into the sensor board (310). The first diverter (210) is correspondingly arranged for each group of the sensors to be tested (311). The gas supply mechanism (100) injects the test standard gas into the corresponding catalytic sensors to be tested (312) at a low flow rate and uniformly through the first diverter (210); A detection board (320) which is connected to the sensor board (310) through a standard connector, and is used for collecting the test data of each catalytic sensor to be tested (312) in each group of the sensors to be tested (311), and uploading the test data to the acquisition and analysis software built in an external PC for analysis.

2. The test system of a catalytic combustion type gas sensor according to claim 1, characterized in that, A plurality of exhaust holes (313) are opened around the catalytic sensors to be tested (312) on the sensor board (310).

3. The test system of a catalytic combustion type gas sensor according to claim 1, characterized in that, The first diverter (210) includes: A first upper diverter body (211) which is hemispherical and has a first intake pipe (215) communicated in the middle. The inner diameter of the first intake pipe (215) is 16 mm; A first lower diverter body (212) which is a circular plate and is detachably connected to the first upper diverter body (211). The first lower diverter body (212) is uniformly communicated with equidistant and equal-length first outlet pipes (216). The inner diameter of the first outlet pipes (216) is 12 mm, and the first outlet pipes (216) are correspondingly arranged for the catalytic sensors to be tested (312); A cover plate (213) which is erected and fixed on the first lower diverter body (212) and is used for buffering the air flow entering from the first intake pipe (215) to ensure that the air flow is evenly dispersed into the plurality of first outlet pipes (216); A first sealing ring (214) which is an O-ring and is used for realizing the sealing between the first upper diverter body (211) and the first lower diverter body (212).

4. The test system for a catalytic combustion type gas sensor according to claim 1, characterized in that, The test system of the catalytic combustion type gas sensor further includes: A diverter rack (230). The first diverter (210) is installed on the lower layer of the diverter rack (230), and the first intake pipes (215) of the plurality of first diverters (210) are in the same plane; The second flow divider (220) is installed on the upper layer of the flow dividing frame (230). The second flow divider (220) is provided with a plurality of output ports, and each output port is hermetically connected to the first intake pipe (215) of the corresponding first flow divider (210) for delivering uniform gas to the plurality of first flow dividers (210); the flow dividing frame (230), the first flow divider (210) and the second flow divider (220) together form a gas filling hood (200); the gas filling hood (200) can move in a direction close to or away from the sensor plate (310); the gas supply mechanism (100) is used to supply test standard gas to the second flow divider (220).

5. The test system of a catalytic combustion type gas sensor according to claim 4, characterized in that, The second flow divider (220) includes: The upper body of the second flow divider (221), which is hemispherical and has a second intake pipe (225) communicating with the middle. The inner diameter of the second intake pipe (225) is 20 mm; The lower body of the second flow divider (222), which is a circular plate and is detachably connected to the upper body of the second flow divider (221); the lower body of the second flow divider (222) is uniformly communicated with equidistant and equal-length second outlet pipes (226). The inner diameter of the second outlet pipe (226) is 16 mm. Each second outlet pipe (226) corresponds to a first intake pipe (215), and the second outlet pipe (226) is hermetically connected to the first intake pipe (215); A cone (223), which is coaxially and fixedly connected to the circular plate for uniformly dispersing the airflow input by the second intake pipe (225) into a plurality of second outlet pipes (226); A second sealing ring (224), which is an O-ring for sealing the upper body of the second flow divider (221) and the lower body of the second flow divider (222).

6. The test system for a catalytic combustion type gas sensor according to claim 4, characterized in that, The gas supply assembly includes: Standard gas cylinders (110), a plurality of which are provided and can hold standard gases with different concentrations; Intake branch pipes (120), which are arranged corresponding to the standard gas cylinders (110). One end of the intake branch pipe (120) is communicated with the corresponding standard gas cylinder (110); Cut-off valves (130), which are connected to each intake branch pipe (120) for controlling the on-off of the corresponding intake branch pipe (120); An intake main pipe (140), one end of which is communicated with the other ends of the plurality of intake branch pipes (120), and the other end is hermetically connected to the second intake pipe (225) of the second flow divider (220); A flow meter (150), which is installed on the intake main pipe (140) for detecting the flow rate of the output test standard gas.

7. The test system of a catalytic combustion type gas sensor according to claim 6, characterized in that, The test system of the catalytic combustion type gas sensor further includes: A counter, which is installed on the sensor plate (310) for calculating the number of times of pin insertion. The measured catalytic sensor (312) is inserted into the sensor plate (310) in a pin insertion manner; the counter is communicatively connected to the detection plate (320).

8. The test system of a catalytic combustion type gas sensor according to claim 6, characterized in that, The counter adopts a rotary dial switch, and each rotation steps one digit for counting.

9. The test system for a catalytic combustion type gas sensor according to claim 1, characterized in that, Installed on the detection plate (320): The sensor detection group, each group corresponding to a group of the sensors to be measured (311), and each group includes a plurality of sensor detection modules, each of the sensor detection modules corresponding to one of the catalytic sensors to be measured (312) for collecting the sensing data of the catalytic sensor to be measured (312), the sensing data including the working current, the supply voltage, and the sensor signal output; The microprocessor, each corresponding to a group of the sensor detection groups, each of the microprocessors being communicatively connected to the corresponding sensor detection group for receiving the corresponding sensing data and sending the test data to the acquisition and analysis software at the PC side, the test data including the sensing data, the temperature, and the humidity.

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