Gas distribution mechanism and gas sensor performance detection system

Abstract

The invention discloses a gas distribution mechanism which comprises a gas distribution unit and a test unit, the gas distribution unit comprises a gas distribution shell, and a gas distribution chamber is formed in an inner cavity of the gas distribution shell; the testing unit comprises a testing shell, and an inner cavity of the testing shell forms a testing chamber. During working, different gases can be injected into the gas distribution chamber through the gas distribution port, the different gases are mixed in the gas distribution chamber, when testing is needed, the control valve is adjusted to enable the testing chamber and the gas distribution chamber to be in a communicated state, and the mixed gases are diffused into the testing chamber. The volume of the gas distribution chamber can be increased, so that the gas dilution times are reduced, and the final gas concentration is ensured; meanwhile, the volume of the gas distribution chamber is greatly different from that of the test chamber, so that gas in the test chamber can be neglected in the gas exchange process of the gas distribution chamber and the test chamber, the final gas concentration of the test chamber is not greatly different from the preset gas concentration, and the test precision is improved. The invention further provides a gas sensor performance detection system which comprises the gas distribution mechanism.

Description

Technical Field

[0001] The present invention relates to the technical field of testing equipment and its peripheral supporting facilities, and particularly to a gas distribution mechanism and a gas sensor performance detection system. Background Art

[0002] Since the performance test of gas-sensitive elements needs to be carried out in a detection gas with a specific concentration, gas distribution is required during gas-sensitive testing. Existing gas distribution methods mainly include synthetic gas distribution, gas sampling bag gas distribution, and gas injection into a gas distribution chamber. Among them, synthetic gas distribution is to mix different gases in a specific ratio to form the required test gas; this method is often used in gas-sensitive tests that require precise control of gas components and concentration ratios, such as mixing different gases to simulate specific environmental conditions. Gas sampling bag gas distribution is to collect and store the required gas in a gas sampling bag, and then control the gas delivery by opening / closing the valve of the bag; this method is often used in occasions where gas-sensitive testing needs to be moved or carried out at a specific location, and it can be conveniently carried and supplied with gas. Gas injection into a gas distribution chamber is to store the required gas in the gas distribution chamber, and then control the injection of the gas into the test system by opening / closing the valve in the chamber; this method is often used in occasions that require rapid and accurate gas supply, and can also be integrated with other sensor testing equipment.

[0003] Existing gas distribution systems often need to be diluted multiple times to reach the target concentration of the prepared gas when preparing low-concentration gases. However, the increase in the number of dilutions is accompanied by the loss of the target gas, and the concentration of the prepared gas will deviate during each dilution process. The actual concentration of the prepared gas after gas distribution will have an obvious gap with the preset gas concentration, and the gas concentration will be further diluted after injecting the prepared gas into the test chamber. Summary of the Invention

[0004] The purpose of the present invention is to provide a gas distribution mechanism and a gas sensor performance detection system to solve the problems existing in the above-mentioned related technologies, reduce gas loss during gas distribution, thereby reducing the gap between the final gas concentration and the preset gas concentration, and improving the test accuracy.

[0005] To achieve the above purpose, the present invention provides the following solutions:

[0006] The present invention provides a gas distribution mechanism, including:

[0007] A gas distribution unit, the gas distribution unit includes a gas distribution housing, the inner cavity of the gas distribution housing forms a gas distribution chamber, the gas distribution housing has a gas distribution port, and the gas distribution port is communicated with the gas distribution chamber to realize injecting gas into the gas distribution chamber and pumping gas out of the gas distribution chamber by using the gas distribution port;

[0008] The test unit, the test unit includes a test housing, the inner cavity of the test housing forms a test chamber, the test housing is connected to the air distribution housing, the test chamber can be communicated with the air distribution chamber and a control valve is arranged between the two.

[0009] Preferably, the air distribution housing is of a split structure, the air distribution housing includes an air distribution main body, an air distribution cover plate and an air distribution base, the air distribution cover plate and the air distribution base are respectively arranged at the top and bottom of the air distribution main body to enclose the air distribution chamber, the air distribution cover plate and the air distribution base are respectively detachably connected to the air distribution main body, and sealing elements are arranged between the air distribution cover plate and the air distribution base and the air distribution main body.

[0010] Preferably, a first fan is arranged on the air distribution cover plate, and the first fan is rotatably arranged on the side of the air distribution cover plate facing the air distribution base.

[0011] Preferably, the number of the air distribution ports is multiple, and the air distribution ports are arranged on the air distribution base; a liquid injection port is further arranged on the air distribution main body, and the liquid injection port is communicated with the air distribution chamber; a heater is further arranged on the air distribution base, and the heater is located on one side of the liquid injection port; sealing joints are arranged on both the air distribution ports and the liquid injection port to block the air distribution ports and the liquid injection port.

[0012] Preferably, the test housing includes a test base and a test main body, the test base is integrally connected to the air distribution main body, the test base is detachably connected to the test main body and encloses the test chamber, and the control valve is arranged between the test base and the test main body.

[0013] Preferably, a second fan is arranged in the test base, and the second fan is rotatably arranged in the test base.

[0014] Preferably, the control valve is a pneumatic butterfly valve, and the test base and the test main body are respectively detachably connected to the control valve by flanges;

[0015] The test main body further has a test air inlet and a test air outlet, and both the test air inlet and the test air outlet are communicated with the test chamber.

[0016] Preferably, the number of the test units is multiple groups, and the test units are circumferentially and evenly arranged around the axis of the air distribution unit.

[0017] Preferably, pressure sensors and humidity sensors are arranged in both the air distribution chamber and the test chamber to monitor the gas states in the air distribution chamber and the test chamber.

[0018] The present invention also provides a gas sensor performance detection system, including the above-mentioned gas distribution mechanism.

[0019] The present invention has achieved the following technical effects compared with the related art: The gas distribution mechanism of the present invention includes a gas distribution unit and a test unit. The gas distribution unit includes a gas distribution housing, and the inner cavity of the gas distribution housing forms a gas distribution chamber. The gas distribution housing has a gas distribution port, and the gas distribution port is connected to the gas distribution chamber to realize injecting gas into the gas distribution chamber and pumping gas from the gas distribution chamber through the gas distribution port; The test unit includes a test housing, and the inner cavity of the test housing forms a test chamber. The test housing is connected to the gas distribution housing, and the test chamber can be connected to the gas distribution chamber and a control valve is provided therebetween.

[0020] During the operation of the gas distribution mechanism of the present invention, different gases can be injected into the gas distribution chamber through the gas distribution port, and the different gases are mixed in the gas distribution chamber. When testing is required, the control valve is adjusted to make the test chamber and the gas distribution chamber in a connected state, and the mixed gas diffuses into the test chamber, facilitating subsequent gas testing. The gas distribution mechanism of the present invention adopts an integrated structure design combining the gas distribution chamber and the test chamber, reducing gas loss during the gas distribution process, making the gas concentration in the test chamber closer to the preset concentration, and improving the gas testing accuracy. In practical applications, the volume of the gas distribution chamber can be increased to reduce the number of gas dilution times and ensure the final gas concentration; while increasing the volume of the gas distribution chamber, making the volume difference between the gas distribution chamber and the test chamber significant, so that the gas in the test chamber can be negligible during the gas exchange process between the gas distribution chamber and the test chamber, making the final gas concentration in the test chamber not much different from the preset gas concentration and improving the testing accuracy.

[0021] The present invention also provides a gas sensor performance detection system, including the above-mentioned gas distribution mechanism. Naturally, the gas sensor performance detection system of the present invention can also achieve the above-mentioned beneficial effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the related art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0023] Figure 1 It is a schematic structural diagram of the gas distribution mechanism disclosed in the embodiments of the present invention;

[0024] Figure 2 It is a schematic structural diagram of the gas distribution unit of the gas distribution mechanism disclosed in the embodiments of the present invention;

[0025] Figure 3 It is a schematic structural diagram of the gas distribution base of the gas distribution mechanism disclosed in the embodiments of the present invention;

[0026] Figure 4 This is a schematic structural diagram of the test unit of the gas distribution mechanism disclosed in the embodiments of the present invention.

[0027] In the figure: 1, gas distribution chamber; 2, test chamber; 3, gas distribution base; 4, test air outlet; 5, test air inlet; 6, control valve; 7, gas distribution cover plate; 8, first fan; 9, sealing element; 10, wiring base; 11, humidity sensor; 12, pressure sensor; 13, gas distribution port; 14, liquid injection port; 15, monitoring element; 16, gold finger socket; 17, flange; 18, test base; 19, second fan; 20, gas distribution pipeline; 21, heater. Specific embodiments

[0028] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0029] The purpose of the present invention is to provide a gas distribution mechanism and a gas sensor performance detection system to solve the problems existing in the above-mentioned related technologies, reduce the gas loss during the gas distribution process, thereby reducing the gap between the final gas concentration and the preset gas concentration, and improving the test accuracy.

[0030] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0031] Embodiment 1

[0032] The present invention provides a gas distribution mechanism. Please refer to Figures 1 - 4 , which includes a gas distribution unit and a test unit. The gas distribution unit includes a gas distribution housing. The inner cavity of the gas distribution housing forms a gas distribution chamber 1. The gas distribution housing has a gas distribution port 13, and the gas distribution port 13 is communicated with the gas distribution chamber 1 to realize injecting gas into the gas distribution chamber 1 and pumping gas from the gas distribution chamber 1 through the gas distribution port 13. The test unit includes a test housing. The inner cavity of the test housing forms a test chamber 2. The test housing is connected to the gas distribution housing. The test chamber 2 can be communicated with the gas distribution chamber 1, and a control valve 6 is provided between the two.

[0033] The gas distribution mechanism of the present invention, during operation, can inject different gases into the gas distribution chamber 1 through the gas distribution port 13. Different gases are mixed in the gas distribution chamber 1. When testing is required, the control valve 6 is adjusted to make the test chamber 2 communicate with the gas distribution chamber 1. The mixed gas diffuses into the test chamber 2, providing convenience for subsequent gas testing. The gas distribution mechanism of the present invention adopts an integrated structure design combining the gas distribution chamber 1 and the test chamber 2, reducing gas loss during the gas distribution process, making the gas concentration in the test chamber 2 closer to the preset concentration, and improving the gas testing accuracy. In practical applications, the volume of the gas distribution chamber 1 can be increased to reduce the number of gas dilution times and ensure the final gas concentration. While increasing the volume of the gas distribution chamber 1, the volume difference between the gas distribution chamber 1 and the test chamber 2 is made significant, so that the gas in the test chamber 2 can be negligible during the gas exchange process between the gas distribution chamber 1 and the test chamber 2, making the final gas concentration in the test chamber 2 not much different from the preset gas concentration and improving the testing accuracy.

[0034] Among them, the gas distribution housing is of a split structure. The gas distribution housing includes a gas distribution main body, a gas distribution cover plate 7, and a gas distribution base 3. The gas distribution cover plate 7 and the gas distribution base 3 are respectively arranged at the top and bottom of the gas distribution main body to enclose the gas distribution chamber 1. The split structure of the gas distribution housing reduces the processing and manufacturing difficulty of the gas distribution housing. The gas distribution cover plate 7 and the gas distribution base 3 are respectively detachably connected to the gas distribution main body, facilitating the disassembly, assembly, and maintenance of the gas distribution housing and the installation and maintenance of internal components. Sealing elements 9 are arranged between the gas distribution cover plate 7 and the gas distribution base 3 and the gas distribution main body to ensure the sealing performance of the gas distribution housing. In practical applications, the sealing element 9 can be selected as an O-ring, which is inexpensive and easy to replace. In this specific embodiment, the gas distribution main body adopts a cylindrical structure to avoid dead corners causing gas accumulation and ensure uniform gas mixing. In practical applications, the shapes of the gas distribution chamber 1 and the test chamber 2 can also be adjusted according to different gas distribution requirements to improve the flexible adaptability of the gas distribution mechanism.

[0035] It should also be noted that a first fan 8 is arranged on the gas distribution cover plate 7. The first fan 8 is rotatably arranged on the side of the gas distribution cover plate 7 facing the gas distribution base 3. The first fan 8 can play a stirring role to make the gas in the gas distribution chamber 1 mix evenly and avoid stratification, providing a strong guarantee for subsequent testing.

[0036] In this specific embodiment, the number of gas distribution ports 13 is multiple. The gas distribution ports 13 are arranged on the gas distribution base 3 and can be connected to the gas injection pipeline, the gas extraction pipeline, and the gas outlet pipeline. Through the gas path, the target gas, the background gas, and the reference gas enter the gas distribution chamber 1. In the non-use state, it can be sealed with a sealing joint. At the same time, the gas distribution main body also has a liquid injection port 14, and the liquid injection port 14 is communicated with the gas distribution chamber 1. For volatile liquids, they can be injected from the liquid injection port 14. To ensure that the gas distribution chamber 1 does not leak gas when the liquid injection port 14 is not in use, a sealing joint is assembled for it. Sealing joints are provided for both the gas distribution port 13 and the liquid injection port 14 to block the gas distribution port 13 and the liquid injection port 14 and ensure the normal operation of the mechanism. At the same time, a heater 21 is also arranged on the gas distribution base 3. The heater 21 is located on one side of the liquid injection port 14. The volatile liquid injected through the liquid injection port 14 will fall on the heater 21 after injection and will be accelerated to volatilize into gas through heat treatment, ensuring the smooth progress of gas distribution.

[0037] Specifically, the test housing includes a test base 18 and a test main body. The test base 18 is connected to the gas distribution main body and they are of an integral structure. The test base 18 serves as the connecting structure between the gas distribution chamber 1 and the test chamber 2. The test base 18 is detachably connected to the test main body and encloses the test chamber 2. The control valve 6 is arranged between the test base 18 and the test main body to control the on-off state between the gas distribution chamber 1 and the test chamber 2. When the gas distribution chamber 1 and the test chamber 2 are in an isolated state, the control valve 6 can block the gas interaction between them and improve the controllability of the gas distribution mechanism.

[0038] Correspondingly, a second fan 19 is arranged in the test base 18. The second fan 19 is rotatably arranged in the test base 18. When the gas distribution chamber 1 and the test chamber 2 are in a connected state, the second fan 19 can accelerate the diffusion of the gas components in the gas distribution chamber 1 into the test chamber 2 and improve the working efficiency of the gas distribution mechanism.

[0039] In this specific embodiment, the control valve 6 adopts a pneumatic butterfly valve, which is convenient for control. The test base 18 and the test main body are respectively detachably connected to the control valve 6 by flanges 17, which is convenient for disassembly and assembly. The sample to be tested can also extend into the test chamber 2 to react with the gas in the gas distribution chamber 1 to meet different test requirements.

[0040] It should also be noted that the test body also has a test air inlet 5 and a test air outlet 4. Both the test air inlet 5 and the test air outlet 4 are connected to the test chamber 2, and gas can be directly introduced into the test chamber 2 from the gas path. In practical applications, the test air inlet 5 and the test air outlet 4 can also be used for cleaning to clean the test chamber 2. The test chamber 2 is provided with multiple groups of gas paths to meet more simulated gas distribution conditions, and is internally equipped with multiple circuits. In addition, in practical applications, various environmental simulation devices such as environmental heating and vibration can also be installed in the test chamber 2.

[0041] More specifically, the number of test units is multiple groups, and the test units are circumferentially and evenly distributed around the axis of the gas distribution unit, allowing multiple groups of gas sensors to be tested simultaneously. In this specific embodiment, the number of test units is six groups, circumferentially and evenly distributed around the axis of the gas distribution unit; in practical applications, the number and distribution of test units can be adjusted according to different test requirements to improve the flexible adaptability of the gas distribution mechanism.

[0042] At the same time, monitoring components 15 are provided in both the gas distribution chamber 1 and the test chamber 2 to monitor the gas state in the gas distribution chamber 1 and the test chamber 2. In this specific embodiment, the monitoring component 15 includes a pressure sensor 12 and a humidity sensor 11, which monitor the pressure and humidity in the gas distribution chamber 1 and the test chamber 2, providing more data basis for the test environment. In practical applications, other types of monitoring components 15 can also be selected to meet different monitoring working conditions.

[0043] In addition, the gas distribution base 3 is also equipped with a gas distribution pipeline 20. The gas distribution pipeline 20 can be selected as a KF50 specification pipeline and can be used to connect to an aviation plug. The test chamber 2 is also provided with a wiring base 10. The wiring base 10 is located on the side of the test body away from the gas distribution chamber 1. The wiring base 10 is a KF50 to KF40 conversion and can be externally connected to an aviation plug. The wiring base 10 can also be connected to the side view through a flange 17. Its function is to connect the lines leading out the internal electronic components of the test chamber 2, and is equipped with a gold finger socket 16, a pressure sensor 12, and a humidity sensor 11. The function of the gold finger socket 16 is to connect the test board loaded with the gas sensor. The gold finger socket 16 has a total of 18 pairs of electrodes, which can provide at least 4 samples for data sampling. Six groups of test chambers 2 can provide at least 24 gas sensors for testing; compared with using probes to connect test samples in the prior art, the present invention uses the gold finger socket 16 to connect test samples, and the connection is more stable. The functions of the pressure sensor 12 and the humidity sensor 11 are to monitor the pressure and humidity in the test chamber 2, providing more data reliance for the test environment.

[0044] Embodiment 2

[0045] This embodiment provides a gas sensor performance detection system, including a gas sensor and the gas distribution mechanism of Embodiment 1, which can effectively improve the detection accuracy and detection efficiency.

[0046] The gas distribution mechanism of the present invention increases the volume of the gas distribution chamber 1, and reduces the dilution times through the sufficiently large gas distribution chamber 1; the volume of the gas distribution chamber 1 is 50 L, and the volume of the test chamber 2 is 100 mL. Since the gas volume of the test chamber 2 is much different from that of the gas distribution chamber 1, the gas in the test chamber 2 can be ignored during the gas exchange process between the two chambers, so that the final gas concentration in the test chamber 2 is not much different from the preset gas concentration, improving the test accuracy.

[0047] It should also be noted here that according to the requirements of Article 4, 4.1-b in the "Test Method for Metal Oxide Semiconductor Gas Sensors" (GB / T 15653-1995), the volume of the box should ensure that the average volume occupied by each element therein is not less than 1 L. Therefore, in actual applications, the volume of the gas distribution chamber 1 can be set according to the number of gas sensors to be measured. For example, the volume of the gas distribution chamber 1 can be set to the number of gas sensors to be measured * (1.5 - 3) L. At the same time, the volume ratio of the test chamber 2 to the volume of the gas distribution chamber 1 is set not to be greater than 1%. In this specific embodiment, the volume ratio of the gas distribution chamber 1 to the test chamber 2 is 100:1 to 100:0.2, so that the volumes of the gas distribution chamber 1 and the test chamber 2 are extremely different. During the gas exchange process between the gas distribution chamber 1 and the test chamber 2, the gas in the test chamber 2 can be ignored, ensuring the gas distribution accuracy.

[0048] In the present invention, specific examples are used to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A valve train, characterized in that: include: A gas distribution unit, the gas distribution unit comprising a gas distribution housing, the inner cavity of the gas distribution housing forming a gas distribution chamber, the gas distribution housing having a gas distribution port, the gas distribution port being in communication with the gas distribution chamber, so as to realize gas injection into the gas distribution chamber and gas extraction from the gas distribution chamber by using the gas distribution port; The test unit comprises a test housing, the inner cavity of the test housing forms a test chamber, the test housing is connected to the gas distribution housing, the test chamber can be communicated with the gas distribution chamber and a control valve is arranged between the two.

2. The valve train according to claim 1, characterized in that: The gas distribution housing is a split structure, and the gas distribution housing includes a gas distribution body, a gas distribution cover plate and a gas distribution base. The gas distribution cover plate and the gas distribution base are respectively arranged on the top and bottom of the gas distribution body to enclose the gas distribution chamber. The gas distribution cover plate and the gas distribution base are respectively detachably connected to the gas distribution body, and sealing elements are arranged between the gas distribution cover plate and the gas distribution base and the gas distribution body.

3. The valve train according to claim 2, characterized in that: The air distribution cover plate is provided with a first fan, and the first fan is rotatably provided on a side of the air distribution cover plate facing the air distribution base.

4. The valve train according to claim 2, characterized in that: There are multiple gas distribution ports, and each of the gas distribution ports is arranged on the gas distribution base; the gas distribution body is also provided with a liquid injection port, and the liquid injection port is connected with the gas distribution chamber; the gas distribution base is also provided with a heater, and the heater is located on one side of the liquid injection port; the gas distribution port and the liquid injection port are both provided with sealing joints to seal the gas distribution port and the liquid injection port.

5. The valve train according to claim 2, characterized in that: The test housing comprises a test base and a test body, wherein the test base is integrally connected to the gas distribution body, the test base and the test body are detachably connected to form the test chamber, and the control valve is arranged between the test base and the test body.

6. The valve train according to claim 5, characterized in that: A second fan is arranged in the test base, and the second fan is rotatably arranged in the test base.

7. The valve train according to claim 5, characterized in that: The control valve is a pneumatic butterfly valve, and the test base and the test body are detachably connected to the control valve by flanges respectively; The test body also has a test air inlet and a test air outlet, and both the test air inlet and the test air outlet are connected to the test chamber.

8. The valve train according to any one of claims 1 to 7, characterized in that: The number of the test units is multiple groups, and the test units are evenly distributed circumferentially around the axis of the gas distribution unit.

9. The valve train according to any one of claims 1 to 7, characterized in that: The gas distribution chamber and the test chamber are both provided with a pressure sensor and a humidity sensor to monitor the gas state in the gas distribution chamber and the test chamber.

10. A gas sensor performance detection system, characterized in that: A valve mechanism comprising any one of claims 1 to 9.

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