Electronic nose air inlet mechanism, split type electronic nose and control method of split type electronic nose

Abstract

The invention discloses an electronic nose air inlet mechanism, a split type electronic nose and a control method of the split type electronic nose, the split type electronic nose comprises a gas general detection assembly and an electronic nose air inlet mechanism, the gas general detection assembly can conveniently carry out quick change on a quick change gas sensor redundancy detection module in a side mounting groove; therefore, through the type combination of the general gas sensor detection module and each quick-change gas sensor redundancy detection module, the system is suitable for detection of different detected targets, and the universality is excellent; meanwhile, the effect of multiple tests can be achieved through one test, the test error is greatly reduced, and the test efficiency is improved; in addition, the chambers are mutually independent, so that the detection precision is further improved. According to the control method of the split type electronic nose, the split type electronic nose is simple and reasonable in logic, self-checking and self-cleaning of filter elements of filters at all levels are achieved, and the functions of reasonably selecting a quick-change gas sensor redundancy detection module combination and adjusting the detection pressure of detected gas according to the type of the detected gas are achieved.

Description

Technical Field

[0001] This invention relates to the technical field of testing or analyzing materials by measuring their chemical or physical properties, and specifically to an electronic nose air intake mechanism, a split-type electronic nose, and a control method thereof. Background Technology

[0002] An electronic nose, also known as an odor scanner, is a rapidly developing gas detection-based rapid detection instrument. It uses specific sensors and pattern recognition systems to quickly provide overall information about the sample, indicating its implicit characteristics. The core component of an electronic nose is the gas sensor. Gas sensors can be classified into many types based on their operating principles, including metal oxide type, electrochemical type, conductive polymer type, mass type, and photoionization type.

[0003] Existing electronic noses lack any air intake filtration mechanism, thus relying on direct inhalation and detection of the target gas during the testing process. The applicant of this application discovered that certain non-target gases and impurities can interfere with the gas sensor's recognition signal, thereby affecting detection accuracy.

[0004] Furthermore, due to the different detection targets or purposes, electronic noses require specific combinations of gas sensors for detection. Therefore, please refer to Chinese patent applications with publication numbers CN119936122A and CN119959474A, etc. Existing electronic noses are all specialized devices, capable of detecting only one type of target or a broad category of targets, and classifying them into smaller subcategories based on the collected information. This results in very poor versatility. Different electronic noses need to be prepared specifically for different detection targets or purposes, incurring huge costs and limiting the application and promotion of electronic noses. Moreover, existing miniaturized and compact electronic noses lack redundant detection capabilities (redundant arrangement). To meet processing algorithm requirements and ensure detection accuracy, multiple repeated measurements are required, leading to low detection efficiency and poor operational convenience.

[0005] Solving these problems is now a top priority. Summary of the Invention

[0006] To address the technical problems of insufficient detection accuracy and the fact that existing electronic noses are all dedicated detection devices with poor versatility, this invention provides an electronic nose air intake mechanism, a split-type electronic nose, and a control method thereof.

[0007] The technical solution is as follows:

[0008] The first aspect of this application relates to an electronic nose air intake mechanism, comprising an air pump having an inlet and an outlet, the outer end of which is connected to a filter assembly, a pressure sensor being installed inside the air pump, and the filter assembly comprising an assembly housing, on which are integrated an inlet nozzle, an outlet nozzle, an inlet / outlet passage communicating with the inlet / outlet, an exhaust passage communicating with the inlet / outlet passage and the outlet nozzle, and a filter passage communicating with the inlet / outlet passage. At least two stages of filters are sequentially arranged on the filter passage, and the inlet end of each filter is connected to the inlet nozzle via a corresponding inlet passage. An on / off actuator is installed on the assembly housing for switching the on / off states of the exhaust passage and each inlet passage; when the on / off actuator keeps the exhaust passage open, all inlet passages are cut off by the on / off actuator; when the on / off actuator keeps any one inlet passage open, the exhaust passage and the remaining inlet passages are cut off by the on / off actuator.

[0009] The above-mentioned electronic nose air intake mechanism not only allows the actuator to connect and disconnect the corresponding air intake channel according to the type of gas being tested and the testing environment, so that the gas being tested can be filtered through corresponding filters at each stage while being drawn into the air pump, removing interfering gases and impurities, thereby effectively improving the recognition accuracy of subsequent gas sensors and thus improving the detection accuracy of the electronic nose; it also allows the gas being tested to be pressurized according to the type of gas being tested and the testing requirements, meeting the needs of certain gases that require testing under specific pressures, further improving the applicability and versatility of the electronic nose; at the same time, it also has the function of self-testing and self-cleaning the filter elements of each stage, further ensuring the detection accuracy.

[0010] The second aspect of this application relates to a split-type electronic nose, including a universal gas detection assembly and the aforementioned electronic nose air intake mechanism. The universal gas detection assembly includes a detection box and an air intake splitter assembly and an exhaust assembly respectively disposed at both ends of the detection box. The exhaust nozzle is connected to the air intake end of the air intake splitter assembly via a pipeline. The detection box is provided with a central container and a plurality of side mounting slots distributed circumferentially around the central mounting slot. A universal gas sensor detection module is installed in the central container. The universal gas sensor detection module and the central container together form a universal sensor detection chamber that connects the air intake splitter assembly and the exhaust assembly. Each of the side mounting slots is equipped with a quick-change redundant gas sensor detection module. Each quick-change redundant gas sensor detection module and the corresponding side mounting slot respectively form a quick-change sensor detection chamber that connects the air intake splitter assembly and the exhaust assembly. A quick-change sealing plate that can be detachably covered at the opening of the corresponding side mounting slot is installed on the outer wall of the detection box.

[0011] The above-mentioned split-type electronic nose not only possesses all the advantages of the aforementioned electronic nose air intake mechanisms, but also, through the inclusion of a universal sensor detection chamber with a built-in universal gas sensor detection module and multiple quick-change sensor detection chambers with built-in redundant quick-change gas sensor detection modules, the universal gas sensor detection module, which is versatile and does not require frequent replacement, is installed in the central container. The redundant quick-change gas sensor detection modules, which require adaptive adjustment for different detection targets, are installed in the quick-change sensor detection chambers located around the universal sensor detection chamber. Furthermore, the easily removable quick-change sealing plates allow for very convenient quick-change of the redundant quick-change gas sensor detection modules in the side mounting slots. The operation is simple and convenient. Thus, through the combination of the universal gas sensor detection module and the various redundant quick-change gas sensor detection modules, a modular sensor array capable of accurately analyzing different target gases is formed, adaptable to the detection of different targets, exhibiting excellent versatility. This makes this electronic nose a complete system capable of adapting to various situations. The universal device, designed for different inspected targets, significantly reduces the investment cost of electronic noses, facilitating their application, promotion, and widespread adoption. Simultaneously, it allows for identical setting of the type and parameters of redundant detection modules for quick-change gas sensors in two or more quick-change sensor detection chambers. This enables a single test to detect a space equivalent to multiple redundant tests, satisfying the data acquisition requirements of the processing algorithm, obtaining high-precision detection results, and significantly improving testing efficiency and operational convenience. Furthermore, the universal gas sensor detection module and each redundant quick-change gas sensor detection module are located in their own independent chambers, eliminating any interference and further enhancing detection accuracy. The universal gas detection assembly and the electronic nose air intake mechanism adopt a split structure, both extremely compact. Different air intake mechanisms can be used depending on the gas being tested, meeting the requirements for miniaturization and modularization, offering high integration and excellent portability.

[0012] The third aspect of this application relates to a control method for the aforementioned split-type electronic nose, comprising the following steps:

[0013] S1. Check the condition of the filter elements of each stage of the electronic nose air intake mechanism to ensure they are functioning properly, following these steps:

[0014] S11, Air intake nozzle connects to air;

[0015] S12, The on / off actuator keeps the air intake passage connected to the first-stage filter open until the air pump is full of air;

[0016] S13, The on / off actuator cuts off the exhaust passage and all intake passages;

[0017] S14. The air pump compresses the internal air until the pressure sensor detects that the internal air pressure of the air pump has reached the self-test set value.

[0018] S15. The on / off actuator keeps the air intake passage connected to the first-stage filter open until the internal air pressure of the air pump returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, proceed to step S2; if no, proceed to step S3.

[0019] S2. Clean the filter elements of each stage of the electronic nose air intake mechanism according to the following steps:

[0020] S21, The on / off actuator connects the intake passage that is connected to the last stage filter;

[0021] S22. After the air pump is filled with air, the air pump quickly empties the air inside and determines whether the number of repetitions of step S22 is greater than the repetition threshold: if yes, after the air pump is filled with air, proceed to step S23; otherwise, repeat step S22.

[0022] S23. After the on / off actuator cuts off the exhaust passage and all intake passages, the air pump compresses the internal air until the pressure sensor detects that the internal air pressure of the air pump has reached the self-test set value.

[0023] S24. The on / off actuator connects the air intake channel connected to the last stage filter until the internal air pressure of the air pump returns to normal pressure, and it is determined whether the time to return to normal pressure is greater than the time threshold: if yes, replace the filter element of the last stage filter first, and then the on / off actuator connects the air intake channel connected to the previous stage filter, and then proceed to step S25; if no, the on / off actuator connects the air intake channel connected to the previous stage filter, and then proceed to step S25.

[0024] S25. After the air pump is filled with air, the air pump quickly empties the air inside and determines whether the number of repetitions of step S25 is greater than the repetition threshold: if yes, after the air pump is filled with air, proceed to step S26; if no, repeat step S25.

[0025] S26. After the on / off actuator cuts off the exhaust passage and all intake passages, the air pump compresses the internal air until the pressure sensor detects that the internal air pressure of the air pump has reached the self-test set value.

[0026] S27. The on / off actuator connects the previously connected air intake channel until the internal air pressure of the air pump returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, replace the filter element of the first-stage filter closest to the unobstructed air intake channel and proceed to step S28; otherwise, proceed to step S28.

[0027] S28. Determine whether the primary filter closest to the unobstructed air intake channel is the first-stage filter: If yes, after the air pump empties the internal air, proceed to step S3; if no, after the air pump empties the internal air, the on / off actuator connects the air intake channel connected to the previous primary filter, and then return to step S25.

[0028] S3. Detect the gas to be tested, following these steps:

[0029] S31. Connect the air inlet nozzle to the gas being tested;

[0030] S32. Based on the type of gas being tested, determine whether the combination of quick-change gas sensor redundant detection modules installed in the mounting slots on each side meets the detection requirements: if yes, proceed to step S33; if no, replace the combination of quick-change gas sensor redundant detection modules corresponding to the gas being tested and proceed to step S33.

[0031] S33. Depending on the type of gas being tested, the on / off actuator keeps one of the air intake channels corresponding to the gas being tested open until the air pump is filled with the gas being tested.

[0032] S34. Based on the type of gas being tested, determine whether the gas inside the compressed air pump is needed: if yes, proceed to step S35; otherwise, proceed to step S37.

[0033] S35, the on / off actuator cuts off the exhaust passage and all intake passages;

[0034] S36. The air pump compresses the internal gas to be tested until the volume of the gas to be tested is compressed to the detection set value required for its detection.

[0035] S37. The on / off actuator keeps the exhaust passage open until the air pump empties the gas being tested. During this process, all general gas sensor detection modules and quick-change gas sensor redundant detection modules detect the gas being tested.

[0036] The control method of the split-type electronic nose not only has all the advantages of the split-type electronic nose mentioned above, but also enables the split-type electronic nose to realize the functions of self-inspection and self-cleaning of the filter elements of each stage of the filter, as well as the functions of rationally selecting the combination of redundant detection modules of fast-changing gas sensors and adjusting the detection pressure of the gas being tested according to the type of gas being tested. Attached Figure Description

[0037] Figure 1 This is a schematic diagram illustrating the principle of a split-type electronic nose.

[0038] Figure 2 A three-dimensional structural diagram of the electronic nose air intake mechanism;

[0039] Figure 3This is a schematic diagram of the planar structure of the electronic nose air intake mechanism;

[0040] Figure 4 for Figure 3 Sectional view at point AA;

[0041] Figure 5 for Figure 3 Sectional view at point BB;

[0042] Figure 6 This is a schematic diagram of the general-purpose gas detection assembly;

[0043] Figure 7 This is a cross-sectional view of the general gas detection assembly when using the quick-change gas sensor redundant detection module in Implementation 1.

[0044] Figure 8 This is a schematic diagram of the gas universal detection assembly after removing the quick-change sealing plate when using the quick-change gas sensor redundant detection module in Implementation 1.

[0045] Figure 9 for Figure 8 A schematic diagram of the structure after removing the quick-change gas sensor circuit board;

[0046] Figure 10 for Figure 9 A schematic diagram of the structure after removing the rubber gasket pressure plate and sealing gasket;

[0047] Figure 11 This is a cross-sectional view of the general gas detection assembly when using the quick-change gas sensor redundant detection module in Implementation 2.

[0048] Figure 12 This is a schematic diagram of the gas universal detection assembly after removing the quick-change sealing plate when using Implementation Method 2 with the quick-change gas sensor redundant detection module.

[0049] Figure 13 This is a schematic diagram of the volume adjustment component.

[0050] Figure 14 This is a schematic diagram of the structure of the central container. Detailed Implementation

[0051] The present invention will be further described below with reference to the embodiments and accompanying drawings.

[0052] Example 1:

[0053] like Figures 1-5As shown, an electronic nose air intake mechanism mainly includes an air pump 9. A pressure sensor 11 is installed inside the air pump 9, which allows for real-time monitoring of the internal gas pressure. The air pump 9 is provided with an inlet / outlet port 9a for air intake and exhaust, and the outer end of the inlet / outlet port 9a is connected to a filter assembly 10 for filtering the inhaled air.

[0054] The filter assembly 10 includes an assembly housing 10a, on which an intake nozzle 10c for air intake and an exhaust nozzle 10d for air exhaust are mounted. The assembly housing 10a internally integrates an intake / exhaust passage 10b communicating with the intake / exhaust port 9a, an exhaust passage 10e communicating with the intake / exhaust passage 10b and the exhaust nozzle 10d, and a filter passage 10f communicating with the intake / exhaust passage 10b. At least two stages of filters 10g are sequentially arranged on the filter passage 10f. Specifically, the filter passage 10f may have only one stage of filters 10g, or it may have multiple stages of filters 10g. The filter 10g furthest from the intake / exhaust passage 10b is the first stage filter 10g, and the filter 10g closest to the intake / exhaust passage 10b is the last stage filter 10g. Simultaneously, the intake end of each filter 10g is connected to the intake nozzle 10c through a corresponding intake passage 10h. An on / off actuator 10i is installed on the assembly housing 10a to switch the on / off state of the exhaust passage 10e and each intake passage 10h.

[0055] Therefore, when the on / off actuator 10i keeps the exhaust passage 10e open, all intake passages 10h are cut off by the on / off actuator 10i. At this time, the gas inside the air pump 9 is discharged to the outside through the exhaust nozzle 10d. When the on / off actuator 10i keeps any intake passage 10h open, the exhaust passage 10e and the other intake passages 10h are all cut off by the on / off actuator 10i. At this time, outside gas is drawn into the air pump 9 through the intake nozzle 10c and the open intake passage 10h. If the open intake passage 10h is the intake passage connected to the first-stage filter 10g... In channel 10h, the inhaled gas will be filtered sequentially through all filters 10g before being drawn into the air pump 9. If the unobstructed intake channel 10h is connected to the last filter 10g, the inhaled gas will be filtered sequentially through only the last filter 10g before being drawn into the air pump 9. If the unobstructed intake channel 10h is connected to one of the intermediate filters 10g, the inhaled gas will be filtered sequentially through the corresponding first filter 10g to the last filter 10g before being drawn into the air pump 9.

[0056] Therefore, the electronic nose air intake mechanism can not only connect and disconnect the corresponding air intake channel 10h according to the type of gas being tested and the detection environment, so that the gas being tested can be filtered through the corresponding filters 10g at each stage while being drawn into the air pump 9, removing interfering gases and impurities, thereby effectively improving the recognition accuracy of the subsequent gas sensor and thus improving the detection accuracy of the electronic nose; but also can precisely pressurize the gas being tested according to the type of gas being tested and the detection requirements, meeting the needs of some specific gases that need to be detected under specific pressure, further improving the applicability and versatility of the electronic nose; at the same time, it also has the function of self-inspection and self-cleaning of the filter elements of each stage of the filter 10g; please refer to Example 3 for details.

[0057] Regarding the 10g filters at each level, the most versatile 10g filter is placed in the last stage, and the least versatile 10g filter is placed in the first stage. The versatility of the intermediate 10g filters increases progressively towards the last stage. The filter element of the 10g filter can be a physical filter element capable of removing solids, liquids, and aerosols, or a chemical adsorbent filter element capable of removing specific chemical gases, such as activated carbon.

[0058] It should be noted that the assembly housing 10a is equipped with a removable housing cover, which allows the filter element of the filter 10g to be replaced by removing the housing cover.

[0059] Please see Figure 4 The on / off actuator 10i includes an actuator push rod 10i1 and an actuator motor 10i2 for controlling the reciprocating movement of the actuator push rod 10i1. The actuator push rod 10i1 has an exhaust port 10i11 and an intake port 10i12. When the actuator motor 10i2 connects the exhaust port 10i11 of the actuator push rod 10i1 to the exhaust channel 10e, the intake port 10i12 is not connected to any of the intake channels 10h. When the actuator motor 10i2 connects the intake port 10i12 of the actuator push rod 10i1 to any one of the intake channels 10h, the exhaust port 10i11 is not connected to the exhaust channel 10e. Furthermore, the actuator motor 10i2 can also cause the actuator push rod 10i1 to simultaneously block the exhaust channel 10e and all the intake channels 10h, thereby achieving precise control of the on / off state of the exhaust channel 10e and each intake channel 10h.

[0060] Please see Figures 2-5The air pump 9 includes an air cylinder 9b with an air chamber 9b1. In this embodiment, the air cylinder 9b is preferably cylindrical. The inlet and outlet 9a are located at one end of the air chamber 9b1, and the inner end of the inlet and outlet 9a communicates with the air chamber 9b1. A piston 9c and a piston actuator 9d for moving the piston 9c closer to or away from the inlet and outlet 9a are installed in the air chamber 9b. A pressure balancing valve 9e communicating with the air chamber 9b1 is installed at the end of the air cylinder 9b away from the inlet and outlet 9a. Therefore, by controlling the movement of the piston 9c through the piston actuator 9d, the air chamber 9b1 can be inhaled and exhausted. Specifically, when the piston actuator 9d moves the piston 9c away from the inlet and outlet 9a, the outside gas enters the air chamber 9b1 sequentially through the filter assembly 10 and the inlet and outlet 9a; when the piston actuator 9d moves the piston 9c closer to the inlet and outlet 9a, the gas in the air chamber 9b1 is discharged sequentially through the inlet and outlet 9a and the filter assembly 10.

[0061] A motor mounting plate 9b2 is provided at the end of the air cylinder 9b furthest from the inlet / outlet port 9a. The piston actuator 9d is a piston drive motor mounted on the motor mounting plate 9b2. The motor shaft of this piston drive motor is an extended motor shaft, the outer end of which is rotatably mounted on the end of the air cylinder 9b near the inlet / outlet port 9a, thus ensuring the stability and reliability of the extended motor shaft's rotation. Simultaneously, external threads are formed on the outer circumferential surface of the extended motor shaft, and the piston 9c has an internally threaded hole that forms a lead screw and nut moving pair with the extended motor shaft. A translation guide rod 9f parallel to the extended motor shaft is also provided in the air chamber 9b1, and the piston 9c slides in conjunction with the translation guide rod 9f. Therefore, by rotating the extended motor shaft back and forth, the position of the piston 9c in the air chamber 9b1 can be precisely controlled.

[0062] Furthermore, by setting a pressure balancing valve 9e, the internal pressure of the air cylinder 9b can be balanced. Specifically, the vent hole 9b21 on the motor mounting plate 9b2 allows external gas to enter sequentially through the pressure balancing valve 9e and the vent hole 9b21 when the piston 9c is close to the inlet / outlet port 9a, and internal gas to be discharged sequentially through the pressure vent hole 9b21 and the balancing valve 9e when the piston 9c is away from the inlet / outlet port 9a.

[0063] Further, please see Figure 5 The piston 9c is equipped with a safety valve 9f that connects the two sides of the piston 9c. When the pressure in the air chamber 9b1 exceeds the limit, the gas in the air chamber 9b1 will be automatically discharged to protect the safety of the air cylinder 9b.

[0064] Please see Figure 4 and Figure 5The pressure sensor 11 is installed at one end of the air chamber 9b1 where the air inlet and outlet 9a are provided. The air cylinder 9b is equipped with an air inlet and outlet control circuit board 12. The on / off actuator 10i, the piston actuator 9d and the pressure sensor 11 are all electrically connected to the air inlet and outlet control circuit board 12, thereby enabling the linkage control of various electrical components.

[0065] Example 2:

[0066] like Figures 6-14 As shown, a split-type electronic nose includes a universal gas detection assembly and the electronic nose air intake mechanism of Embodiment 1. The universal gas detection assembly includes a detection box 1 and an air intake diversion assembly 2 and an exhaust assembly 3 respectively disposed at both ends of the detection box 1. The exhaust nozzle 10d is connected to the air intake end of the air intake diversion assembly 2 through a pipeline.

[0067] The testing box 1 includes a central container 1a and multiple side mounting slots 1b, which are circumferentially distributed around the central mounting slot 1a. In this embodiment, each side mounting slot 1b is recessed into the circumferential side wall of the testing box 1 surrounding the central mounting slot 1a. Simultaneously, quick-change sealing plates 8 are installed on the outer wall of the testing box 1, each capable of being detachably covered at the opening of its corresponding side mounting slot 1b. Therefore, opening the quick-change sealing plate 8 exposes the corresponding side mounting slot 1b. Taking the overall structure of the testing box 1 as a cuboid as an example, the intake splitter assembly 2 and the exhaust assembly 3 are respectively located at both ends of the testing box 1. The remaining four circumferential side walls of the testing box 1 are all recessed to form side mounting slots 1b, which are covered by quick-change sealing plates 8. Thus, the testing box 1 contains one central container 1a and four side mounting slots 1b. By installing and removing the quick-change sealing plates 8, the equipment and components in the side mounting slots 1b can be easily operated, replaced, and maintained.

[0068] In this embodiment, a universal gas sensor detection module 4 is installed in the central container 1a. The universal gas sensor detection module 4 and the central container 1a together form a universal sensor detection chamber 1a1 that connects the intake diversion assembly 2 and the exhaust assembly 3. Quick-change gas sensor redundant detection modules 5 are installed in the side mounting slots 1b. Each quick-change gas sensor redundant detection module 5 and the corresponding side mounting slot 1b together form a quick-change sensor detection chamber 1b1 that connects the intake diversion assembly 2 and the exhaust assembly 3.

[0069] Therefore, in this embodiment, the universal gas sensor detection module 4, which is versatile and does not require frequent replacement, is installed in the central container 1a (replacing it is relatively troublesome). The quick-change gas sensor redundant detection module 5, which requires adaptive adjustment for different detection targets, is installed in the quick-change sensor detection chamber 1b1 located around the universal sensor detection chamber 1a1. By setting up a quick-change sealing plate 8 that is easy to install and remove, the quick-change gas sensor redundant detection module 5 in the side mounting slot 1b can be quickly replaced. The operation is simple and convenient. Thus, by combining the universal gas sensor detection module 4 with the various quick-change gas sensor redundant detection modules 5, a modular sensor array capable of accurately analyzing different target gases is formed, which is suitable for the detection of different targets and has excellent versatility. This makes the electronic nose a universal device applicable to different targets, which greatly reduces the investment cost of the electronic nose and is conducive to the application, promotion and popularization of the electronic nose. Meanwhile, the type and parameters of the redundant detection modules 4 of the quick-change gas sensors in two or more quick-change sensor detection chambers 1b1 can be set to be exactly the same, so that a single test can detect space 9b1, which is equivalent to the effect of multiple redundant tests. This not only meets the data acquisition requirements of the processing algorithm and obtains high-precision detection results, but also greatly improves the testing efficiency and the convenience of the detection operation.

[0070] Furthermore, the universal gas sensor detection module 4 and each quick-change gas sensor redundant detection module 5 are located in their own independent chambers to detect gases, without any interference between them, thereby further improving the detection accuracy. Moreover, the universal gas detection assembly and the electronic nose air intake mechanism adopt a split structure, and the structure of both parts is extremely compact. The electronic nose air intake mechanism with different air intake volumes can be replaced according to the detection needs of the gas being tested, meeting the application requirements of miniaturization and modularization, with high integration and excellent portability.

[0071] Different quick-change gas sensor redundant detection modules 5 have different requirements for detection space; a reasonable detection space volume can effectively improve detection accuracy. Therefore, please refer to... Figure 7 and Figure 11 Each quick-change sensor detection chamber 1b1 is equipped with a volume adjustment component 6 for adjusting the volume of the quick-change sensor detection chamber 1b1. By setting the volume adjustment component 6, the volume of the quick-change sensor detection chamber 1b1 can be adaptively adjusted according to the different targets being detected and the needs of the current quick-change gas sensor redundant detection module 5, thereby not only improving the detection accuracy but also further enhancing the versatility of the gas universal detection assembly.

[0072] In this embodiment, each quick-change sensor detection chamber 1b1 has a volume adjustment section with the same width at each position. The volume adjustment component 6 is installed in the volume adjustment section so that the volume adjustment component 6 can maintain good airtightness when adjusting the volume of the quick-change sensor detection chamber 1b1.

[0073] Specifically, each volume adjustment assembly 6 includes a slider mounting plate 6a installed at one end of the corresponding volume adjustment section along its length, and a volume adjustment slider 6b slidably mounted on the slider mounting plate 6a along the length of the volume adjustment section. The mounting end face and the outer edges on both sides in the width direction of the slider mounting plate 6a are fixedly connected to the cavity wall of the corresponding volume adjustment section without gaps. That is, the slider mounting plate 6a is fixedly installed at one end of the volume adjustment section along its length, and extends along the length of the volume adjustment section. Furthermore, there are no gaps between the mounting end (inner end) and the outer edges on both sides in the width direction of the slider mounting plate 6a and the cavity wall of the corresponding volume adjustment section. The volume adjustment slider 6b is slidably mounted on the outer end of the slider mounting plate 6a along its length direction, and its bottom surface and the outer edges on both sides in the width direction are slidably fitted to the cavity wall of the corresponding volume adjustment section without gaps.

[0074] Therefore, when it is necessary to reduce the volume of the quick-change sensor detection chamber 1b1, the volume adjustment slider 6b slides away from the slider mounting plate 6a (slides outward); when it is necessary to increase the volume of the quick-change sensor detection chamber 1b1, the volume adjustment slider 6b slides towards the slider mounting plate 6a (slides inward). This design not only allows for flexible adjustment of the volume of the quick-change sensor detection chamber 1b1 by sliding the volume adjustment slider 6b, but also ensures good airtightness.

[0075] Furthermore, the bottom surface of the volume adjustment slider 6b and the outer edges of both sides in the width direction are equipped with a sealing layer that is interference-fitted with the cavity wall of the corresponding volume adjustment section. This not only ensures good airtightness, but also makes it difficult for the volume adjustment slider 6b to slide under gas pressure (the volume adjustment slider 6b will only slide when a large force is applied by a person). This allows the volume of the sensor detection chamber 1b1 to remain stable after it has been filled, further improving the recognition accuracy.

[0076] Further, please see Figure 7 , Figure 10 and Figure 13The volume adjustment section has recessed guide grooves 1b3 extending along its length on both sides of the groove wall in the width direction. The outer edges of both sides of the volume adjustment slider 6b in the width direction have sliding guide ribs 6b2 that are adapted to the corresponding guide grooves 1b3. Each sliding guide rib 6b2 is slidably embedded in its corresponding guide groove 1b3, effectively improving the stability and reliability of the volume adjustment slider 6b's forward and backward sliding. The outer wall of the sliding guide rib 6b2 also has a sealing layer that is interference-fitted with the corresponding guide groove 1b3, with the effect described above.

[0077] Furthermore, one or both sides of the guide slide 1b3 are provided with adjustment scales distributed along its length (not shown in the figure), so that the operator can accurately know the adjusted volume of the quick-change sensor detection chamber 1b1 according to the adjustment scale position of the volume adjustment slider 6b, which not only improves the convenience of operation, but also enhances the accuracy of volume adjustment.

[0078] Furthermore, a support boss 6b1 is formed on the bottom of the volume adjustment slider 6b away from the slider mounting plate 6a. The outer circumferential edge of the support boss 6b1 has a sealing layer that is interference-fitted with the cavity wall of the corresponding volume adjustment section. This not only ensures good airtightness, but also makes it difficult for the volume adjustment slider 6b to slide under gas pressure. This allows the volume of the sensor detection chamber 1b1 to remain stable after it has been filled. At the same time, it reduces the contact area between the volume adjustment slider 6b and the cavity wall of the volume adjustment section, thus avoiding jamming.

[0079] A detection groove is formed in the middle of the bottom of the side mounting groove 1b. At least two circuit board mounting seats 1b2 are provided at the bottom of the side mounting groove 1b surrounding the detection groove. The quick-change gas sensor redundant detection module 5 has the following two implementation methods:

[0080] Quick-change gas sensor redundant detection module 5 Implementation method 1: Please refer to Figures 7-10 The quick-change gas sensor redundant detection module 5 includes a quick-change gas sensor circuit board 5a, a sealing gasket 5b, and a gasket pressure plate 5c. The quick-change gas sensor circuit board 5a is detachably mounted on all circuit board mounting bases 1b2 (typically using screws or clips). The sealing gasket 5b covers the opening of the detection groove, and the gasket pressure plate 5c presses the sealing gasket 5b firmly against the bottom of the detection groove. The sealing gasket 5b and the detection groove together form a quick-change sensor detection chamber 1b1. At least one dedicated gas sensor 5a1 is integrated on the side of the quick-change gas sensor circuit board 5a closest to the detection groove. The dedicated gas sensor 5a1 is a conventional gas sensor, such as a metal oxide gas sensor.

[0081] The sealing gasket 5b has sealing through holes 5b1 that are adapted to each dedicated gas sensor 5a1. The gasket pressure plate 5c is located on the side of the sealing gasket 5b away from the bottom of the side mounting groove 1b. The gasket pressure plate 5c is detachably connected to the bottom of the side mounting groove 1b (usually by screws or clips). The gasket pressure plate 5c has clearance through holes 5c1 that are adapted to each dedicated gas sensor 5a1. The diameter of each sealing through hole 5b1 is smaller than the diameter of the corresponding clearance through hole 5c1. Each dedicated gas sensor 5a1 passes through the corresponding clearance through hole 5c1 and sealing through hole 5b1 in sequence and then extends into the quick-change sensor detection chamber 1b1. Each dedicated gas sensor 5a1 is interference-fitted with the hole wall of the corresponding sealing through hole 5b1.

[0082] Therefore, by designing that the diameter of the sealing through-hole 5b1 is smaller than the diameter of the corresponding clearance through-hole 5c1 and that each dedicated gas sensor 5a1 is press-fitted with the wall of the corresponding sealing through-hole 5b1, the detection part of the dedicated gas sensor 5a1 can be inserted into the quick-change sensor detection chamber 1b1 while ensuring the airtightness of the quick-change sensor detection chamber 1b1.

[0083] Quick-change gas sensor redundant detection module 5, implementation method 2: Please refer to Figure 11 and Figure 12 The quick-change gas sensor redundant detection module 5 includes a gas detection thin-film sensor 5d and a thin-film sensor pressure plate 5e. The gas detection thin-film sensor 5d is a thin-film gas sensor, which is a gas detection instrument based on metal oxide semiconductor material and belongs to the semiconductor gas sensor category. The gas detection thin-film sensor 5d covers the opening of the detection groove. The thin-film sensor pressure plate 5e is used to press the gas detection thin-film sensor 5d tightly against the bottom of the detection groove. The gas detection thin-film sensor 5d and the detection groove together form a quick-change sensor detection chamber 1b1. The thin-film sensor pressure plate 5e is located on the side of the gas detection thin-film sensor 5d away from the bottom of the side mounting groove 1b and is detachably connected to the bottom of the side mounting groove 1b (usually by screws or clips). The quick-change gas sensor redundant detection module 5 using this implementation can ensure that the quick-change sensor detection chamber 1b1 has excellent airtightness. It should be noted that each gas detection thin-film sensor 5d usually integrates multiple gas sensors, and the types of gas sensors can be the same or different.

[0084] Please see Figure 7 , Figure 11 and Figure 12The central container 1a has a sensor mounting port on the side near the exhaust assembly 3. The universal gas sensor detection module 4 includes a universal gas sensor circuit board 4a that covers the sensor mounting port. The universal gas sensor circuit board 4a and the central container 1a together form a universal sensor detection chamber 1a1. At least one universal gas sensor 4b extending into the universal sensor detection chamber 1a1 is integrated on the side of the universal gas sensor circuit board 4a near the central container 1a. This not only ensures the reliable installation of the universal gas sensor detection module 4, but also allows the universal gas sensor detection module 4 to be replaced. However, the replacement steps are more complicated than those of the quick-change gas sensor redundant detection module 5.

[0085] Furthermore, the universal sensor detection chamber 1a1 is divided into a diffusion space 1a11 and a detection space 1a12 by a centrally located air distribution plate 1a2. The air distribution plate 1a2 has an array of small holes 1a21. The diffusion space 1a11 includes an expansion section 1a111 that gradually increases in size from the air inlet of the universal sensor detection chamber 1a1 and a stable section 1a112 that extends from the end of the expansion section 1a111 away from the air inlet to the air distribution plate 1a2. The expansion section 1a111 has a conical structure, and the stable section 1a112 has a cylindrical structure. The universal gas sensor 4b is located in the detection space 1a12, and the detection space 1a12 is connected to the air outlet of the universal sensor detection chamber 1a1. With this structure, the gas being tested, after entering the detection chamber 1a1 of the universal sensor, can first diffuse rapidly in the expansion section 1a111 of the conical structure, then achieve a relatively stable state in the stable section 1a112 of the cylindrical structure, and then enter the detection space 1a12 through the array of small holes 1a21 on the air distribution plate 1a2. This results in extremely high uniformity of the gas being tested filling the detection space 1a12, which can effectively improve the detection accuracy of the universal gas sensor 4b.

[0086] Please see Figures 6-12 The air intake splitter assembly 2 includes a front housing 2a connected to the detection housing 1, an air intake connector 2b installed on the side of the front housing 2a away from the detection housing 1, and a gas distributor 2c installed on the side of the front housing 2a close to the detection housing 1. The front housing 2a has an air intake channel 2a1 connecting the air intake connector 2b and the gas distributor 2c. The gas distributor 2c integrates exhaust ports 2c1 corresponding to the universal sensor detection chamber 1a1 and the quick-change sensor detection chamber 1b1, respectively. Each exhaust port 2c1 is connected to the air intake port of the corresponding universal sensor detection chamber 1a1 or the air intake port of the quick-change sensor detection chamber 1b1 through a pipeline. Therefore, the gas to be tested enters from the air intake connector 2b and is then guided into the universal sensor detection chamber 1a1 and each quick-change sensor detection chamber 1b1 by the gas distributor 2c and the corresponding pipeline, which is simple and reliable.

[0087] The exhaust assembly 3 includes a rear housing 3a connected to the detection box 1 and several exhaust connectors 3b installed on the side of the rear housing 3a away from the detection box 1. Each exhaust connector 3b is connected to the corresponding universal sensor detection chamber 1a1 or quick-change sensor detection chamber 1b1 through an exhaust channel 3c provided in the rear housing 3a. Therefore, the gas to be detected in the universal sensor detection chamber 1a1 and each quick-change sensor detection chamber 1b1 is guided to the exhaust connector 3b by the corresponding exhaust channel 3c and then discharged by the exhaust connector 3b, which is simple and reliable.

[0088] Meanwhile, a detection control circuit board 7 is installed in the rear housing 3a. This detection control circuit board 7 is electrically connected to the general gas sensor detection module 4 and each quick-change gas sensor redundant detection module 5. The detection control circuit board 7 can control the general gas sensor detection module 4 and each quick-change gas sensor redundant detection module 5 to detect the gas being tested, process the detection information of the general gas sensor detection module 4 and each quick-change gas sensor redundant detection module 5, and transmit the processed information to the outside.

[0089] In this embodiment, the test box 1, the intake split assembly 2, and the exhaust assembly 3 all adopt a split structure to facilitate the maintenance and replacement of internal equipment and electrical components. Specifically, the test box 1, the intake split assembly 2, and the exhaust assembly 3 are all plate structures connected by dedicated connectors.

[0090] Example 3:

[0091] A control method for a split-type electronic nose according to Embodiment 2 is performed according to the following steps:

[0092] S1. Check the condition of the 10g filter cartridges of each stage of the electronic nose air intake mechanism to ensure they are functioning properly, following these steps:

[0093] S11, Air intake nozzle 10c connects to air;

[0094] S12, the on / off actuator 10i keeps the air intake passage 10h connected to the first-stage filter 10g unobstructed until the air pump 9 is filled with air;

[0095] S13, the on / off actuator 10i cuts off the exhaust passage 10e and all intake passages 10h;

[0096] S14. The air pump 9 compresses the internal air until the pressure sensor 11 detects that the air pressure inside the air pump 9 has reached the self-test set value.

[0097] S15. The on / off actuator 10i keeps the air intake channel 10h connected to the first-stage filter 10g unobstructed until the internal air pressure of the air pump 9 returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, it means that the filter element of filter 10g is not in good condition, and proceed to step S2; if no, it means that the filter element of filter 10g is in good condition, and proceed to step S3.

[0098] S2. Clean the 10g filter cartridges of each stage of the electronic nose air intake mechanism according to the following steps:

[0099] S21, the on / off actuator 10i connects to the intake passage 10h, which is connected to the last stage filter 10g;

[0100] S22. After the air pump 9 is filled with air, the air pump 9 quickly empties the air inside and determines whether the number of repetitions of step S22 is greater than the repetition threshold: if yes, after the air pump 9 is filled with air, proceed to step S23; if no, repeat step S22. The purpose of the air pump 9 quickly emptying the air inside is to be able to quickly reverse the discharge of the residue on the filter element of the last stage filter 10g through the air pressure impact force.

[0101] S23. After the on / off actuator 10i cuts off the exhaust passage 10e and all intake passages 10h, the air pump 9 compresses the internal air until the pressure sensor 11 detects that the internal air pressure of the air pump 9 reaches the self-test set value.

[0102] S24. The on / off actuator 10i connects the air intake channel 10h connected to the last stage filter 10g until the internal air pressure of the air pump 9 returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, it means that the filter element of the last stage filter 10g cannot be restored to a good state through self-cleaning, so the filter element of the last stage filter 10g is replaced first, and then the on / off actuator 10i connects the air intake channel 10h connected to the previous stage filter 10g, and proceeds to step S25; if no, it means that the filter element of the last stage filter 10g has been restored to a good state through self-cleaning, and the on / off actuator 10i connects the air intake channel 10h connected to the previous stage filter 10g, and proceeds to step S25.

[0103] S25. After the air pump 9 is filled with air, the air pump 9 quickly empties the air inside and determines whether the number of repetitions of step S25 is greater than the repetition threshold: if yes, after the air pump 9 is filled with air, proceed to step S26; if no, repeat step S25. The purpose of the air pump 9 quickly emptying the air inside is to be able to quickly expel the residue on the filter element of the primary filter 10g, which is closest to the unobstructed air intake channel 10h, through the air pressure impact force.

[0104] S26. After the on / off actuator 10i cuts off the exhaust passage 10e and all intake passages 10h, the air pump 9 compresses the internal air until the pressure sensor 11 detects that the internal air pressure of the air pump 9 reaches the self-test set value.

[0105] S27. The on / off actuator 10i connects the previously connected air intake channel 10h until the internal air pressure of the air pump 9 returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, it means that the filter element of the first-stage filter 10g closest to the unobstructed air intake channel 10h cannot be restored to a good state through self-cleaning, so after replacing the filter element of the first-stage filter 10g closest to the unobstructed air intake channel 10h, proceed to step S28; if no, it means that the filter element of the first-stage filter 10g closest to the unobstructed air intake channel 10h has been restored to a good state through self-cleaning, and proceed to step S28.

[0106] S28. Determine whether the primary filter 10g closest to the unobstructed air intake channel 10h is the first-stage filter 10g: If yes, it means that the filter element of all filters 10g is in good condition. After the air pump 9 empties the internal air, proceed to step S3. If no, after the air pump 9 empties the internal air, the on / off actuator 10i connects the air intake channel 10h connected to the previous primary filter 10g, and then returns to step S25.

[0107] S3. Detect the gas to be tested, following these steps:

[0108] S31, Connect the air inlet nozzle 10c to the gas being tested;

[0109] S32. Based on the type of the gas being tested, determine whether the combination of quick-change gas sensor redundant detection modules 5 installed in the mounting slots 1b on each side meets the detection requirements: if yes, proceed to step S33; if no, replace the combination of quick-change gas sensor redundant detection modules 5 corresponding to the gas being tested and proceed to step S33; thereby, through the type combination of the general gas sensor detection module 4 and each quick-change gas sensor redundant detection module 5, a modular sensor array capable of accurately analyzing the gas being tested is formed.

[0110] S33. Based on the type of gas being tested, determine how many stages of filters 10g are needed for filtration. Then, switch the actuator 10i on and off to keep one of the air intake channels 10h corresponding to the gas being tested unobstructed until the air pump 9 is filled with the gas being tested.

[0111] S34. Based on the type of gas being tested, determine whether the gas inside the compressed air pump 9 is needed: if yes, proceed to step S35; otherwise, proceed to step S37.

[0112] S35, the on / off actuator 10i cuts off the exhaust passage 10e and all intake passages 10h;

[0113] S36, Air pump 9 compresses the internal gas to be tested until the volume of the gas to be tested is compressed to the detection set value required for its detection;

[0114] S37, the on / off actuator 10i keeps the exhaust passage 10e unobstructed until the air pump 9 empties the gas being tested inside. During this process, the universal gas sensor detection module 4 of the gas universal detection assembly and the redundant detection modules 5 of each quick-change gas sensor detect the gas being tested.

[0115] Furthermore, step S32 also includes adjusting the volume of the corresponding quick-change sensor detection chamber 1b1 according to the type of gas being detected using each volume adjustment component 6. This allows the volume of the quick-change sensor detection chamber 1b1 to be adaptively adjusted according to the different targets being detected and the current requirements of the quick-change gas sensor redundant detection module 5, thereby not only improving the detection accuracy but also further enhancing the versatility of the gas universal detection assembly.

[0116] Furthermore, the control method for the split-type electronic nose also includes step S4, which involves self-cleaning the interior of the universal gas detection assembly and the electronic nose air intake mechanism, performed according to the following steps:

[0117] S41, Air intake nozzle 10c is connected to air;

[0118] S42, the on / off actuator 10i keeps the intake passage 10h, which is connected to the last stage filter 10g, unobstructed;

[0119] S43. After the air pump 9 is filled with air, the air pump 9 empties the air inside and determines whether the response values ​​of all general gas sensor detection modules 4 and quick-change gas sensor redundant detection modules 5 are the reference values: if yes, it means that the self-cleaning of the air pump 9 is completed and the machine is stopped; if no, it means that there is still residual gas to be detected in the detection space 9b1 and step S43 is repeated.

[0120] By adding step S4, the internal parts of the gas universal detection assembly and the electronic nose air intake mechanism can be self-cleaned using air, avoiding interference from residual gas from the previous detection to the next detection, and effectively improving detection accuracy.

[0121] Finally, it should be noted that the above description is merely a preferred embodiment of the present invention. Those skilled in the art, under the guidance of the present invention, can make various similar representations without departing from the spirit and claims of the present invention, and such modifications all fall within the protection scope of the present invention.

Claims

1. An electronic nose air intake mechanism, comprising an air pump having an air inlet and an exhaust port, wherein a filter assembly is connected to the outer end of the air inlet and exhaust port, characterized in that: The air pump is equipped with a pressure sensor. The filter assembly includes an assembly housing, which integrates an air inlet nozzle, an air outlet nozzle, an air inlet / outlet passage communicating with the air inlet / outlet, an exhaust passage communicating with the air inlet / outlet passage and the air outlet nozzle, and a filter passage communicating with the air inlet / outlet passage. At least two stages of filters are sequentially arranged on the filter passage. The air inlet end of each filter is connected to the air inlet nozzle through a corresponding air inlet passage. The assembly housing is equipped with an on / off actuator for switching the on / off state of the exhaust passage and each air inlet passage. When the on / off actuator keeps the exhaust passage open, all air inlet passages are cut off by the on / off actuator. When the on / off actuator keeps any air inlet passage open, the exhaust passage and the remaining air inlet passages are cut off by the on / off actuator.

2. The electronic nose air intake mechanism according to claim 1, characterized in that: The on / off actuator includes an actuator push rod and an actuator motor for controlling the back-and-forth movement of the actuator push rod. The actuator push rod has an exhaust port and an intake port. When the actuator motor connects the exhaust port of the actuator push rod to the exhaust channel, the intake port is not connected to any intake channel. When the actuator motor connects the intake port of the actuator push rod to any intake channel, the exhaust port is not connected to the exhaust channel.

3. The electronic nose air intake mechanism according to claim 1, characterized in that: The air pump includes an air cylinder with an air chamber, the air inlet and outlet being located at one end of the air chamber, the inner end of the air inlet and outlet communicating with the air chamber, a piston and a piston actuator for driving the piston closer to or away from the air inlet and outlet being installed in the air chamber, and a pressure balancing valve communicating with the air chamber being installed at the end of the air cylinder away from the air inlet and outlet.

4. The electronic nose air intake mechanism according to claim 3, characterized in that: The pressure sensor is installed at one end of the air chamber where the air inlet and outlet are located. An air inlet and outlet control circuit board is installed in the air cylinder. The on / off actuator, piston actuator and pressure sensor are all electrically connected to the air inlet and outlet control circuit board.

5. A split-type electronic nose, characterized in that: The invention includes a universal gas detection assembly and an electronic nose air intake mechanism as described in any one of claims 1-4. The universal gas detection assembly includes a detection box and an air intake splitter assembly and an exhaust assembly respectively disposed at both ends of the detection box. The exhaust nozzle is connected to the air intake end of the air intake splitter assembly via a pipeline. The detection box is provided with a central container and a plurality of side mounting slots distributed circumferentially around the central mounting slot. A universal gas sensor detection module is installed in the central container. The universal gas sensor detection module and the central container together form a universal sensor detection chamber that connects the air intake splitter assembly and the exhaust assembly. Each of the side mounting slots is equipped with a quick-change redundant gas sensor detection module. Each quick-change redundant gas sensor detection module and the corresponding side mounting slot together form a quick-change sensor detection chamber that connects the air intake splitter assembly and the exhaust assembly. A quick-change sealing plate that can be detachably covered at the opening of the corresponding side mounting slot is installed on the outer wall of the detection box.

6. The split-type electronic nose according to claim 5, characterized in that: Each of the quick-change sensor detection chambers has a volume adjustment section of the same width at each location. Each volume adjustment section is equipped with a volume adjustment component for adjusting the volume of the quick-change sensor detection chamber. Each volume adjustment component includes a slider mounting plate installed at one end of the corresponding volume adjustment section along its length and a volume adjustment slider that is slidably mounted on the slider mounting plate along the length of the volume adjustment section. The mounting end face and the outer edges of both sides of the slider mounting plate in the width direction are fixedly connected to the cavity wall of the corresponding volume adjustment section without gaps. The bottom surface and the outer edges of both sides of the volume adjustment slider in the width direction are slidably fitted to the cavity wall of the corresponding volume adjustment section without gaps.

7. The split-type electronic nose according to claim 5, characterized in that: A detection groove is formed by a recess in the middle of the bottom of the side mounting slot. The bottom of the side mounting slot has at least two circuit board mounting seats surrounding the detection groove. The quick-change gas sensor redundant detection module includes a quick-change gas sensor circuit board detachably mounted on all circuit board mounting seats, a sealing gasket covering the opening of the detection groove, and a gasket pressure plate for pressing the sealing gasket firmly against the bottom of the detection groove. The sealing gasket and the detection groove together form the quick-change sensor detection chamber. At least one [missing information - likely a device or component] is integrated on the side of the quick-change gas sensor circuit board closest to the detection groove. Each gas sensor has a sealing gasket with a sealing through-hole adapted to each gas sensor. The gasket pressure plate is located on the side of the sealing gasket away from the bottom of the side mounting groove and is detachably connected to the bottom of the side mounting groove. The gasket pressure plate has a clearance through-hole adapted to each gas sensor. The diameter of each sealing through-hole is smaller than the diameter of the corresponding clearance through-hole. Each gas sensor passes through the corresponding clearance through-hole and sealing through-hole in sequence and extends into the quick-change sensor detection chamber. Each gas sensor is interference-fitted with the wall of the corresponding sealing through-hole.

8. The split-type electronic nose according to claim 5, characterized in that: A detection groove is formed in the middle of the bottom of the side mounting slot. The quick-change gas sensor redundant detection module includes a gas detection thin film sensor covering the opening of the detection groove and a thin film sensor pressure plate for pressing the gas detection thin film sensor against the bottom of the detection groove. The gas detection thin film sensor and the detection groove together form the quick-change sensor detection chamber. The thin film sensor pressure plate is located on the side of the volume detection thin film sensor away from the bottom of the side mounting slot and is detachably connected to the bottom of the side mounting slot.

9. The split-type electronic nose according to claim 5, characterized in that: The central container has a sensor mounting port on the side near the exhaust assembly. The universal gas sensor detection module includes a universal gas sensor circuit board that covers the sensor mounting port. The universal gas sensor circuit board and the central container together form the universal sensor detection chamber. At least one universal gas sensor extending into the universal sensor detection chamber is integrated on the side of the universal gas sensor circuit board near the central container. The universal sensor detection chamber is divided into a diffusion space and a detection space by a centrally located air distribution plate. The air distribution plate has an array of small holes. The diffusion space includes an expansion section that gradually increases in size from the air inlet of the universal sensor detection chamber and a stable section that extends from the end of the expansion section away from the air inlet to the air distribution plate. The expansion section has a conical structure, and the stable section has a cylindrical structure. The universal gas sensor is located in the detection space, and the detection space is connected to the air outlet of the universal sensor detection chamber.

10. A control method for a split-type electronic nose according to any one of claims 5-9, characterized in that, Follow these steps: S1. Check the condition of the filter elements of each stage of the electronic nose air intake mechanism to ensure they are functioning properly, following these steps: S11, Air intake nozzle connects to air; S12, The on / off actuator keeps the air intake passage connected to the first-stage filter open until the air pump is full of air; S13, The on / off actuator cuts off the exhaust passage and all intake passages; S14. The air pump compresses the internal air until the pressure sensor detects that the internal air pressure of the air pump has reached the self-test set value. S15. The on / off actuator keeps the air intake passage connected to the first-stage filter open until the internal air pressure of the air pump returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, proceed to step S2; if no, proceed to step S3. S2. Clean the filter elements of each stage of the electronic nose air intake mechanism according to the following steps: S21, The on / off actuator connects the intake passage that is connected to the last stage filter; S22. After the air pump is filled with air, the air pump quickly empties the air inside and determines whether the number of repetitions of step S22 is greater than the repetition threshold: if yes, after the air pump is filled with air, proceed to step S23; otherwise, repeat step S22. S23. After the on / off actuator cuts off the exhaust passage and all intake passages, the air pump compresses the internal air until the pressure sensor detects that the internal air pressure of the air pump has reached the self-test set value. S24. The on / off actuator connects the air intake channel connected to the last stage filter until the internal air pressure of the air pump returns to normal pressure, and it is determined whether the time to return to normal pressure is greater than the time threshold: if yes, replace the filter element of the last stage filter first, and then the on / off actuator connects the air intake channel connected to the previous stage filter, and then proceed to step S25; if no, the on / off actuator connects the air intake channel connected to the previous stage filter, and then proceed to step S25. S25. After the air pump is filled with air, the air pump quickly empties the air inside and determines whether the number of repetitions of step S25 is greater than the repetition threshold: if yes, after the air pump is filled with air, proceed to step S26; if no, repeat step S25. S26. After the on / off actuator cuts off the exhaust passage and all intake passages, the air pump compresses the internal air until the pressure sensor detects that the internal air pressure of the air pump has reached the self-test set value. S27. The on / off actuator connects the previously connected air intake channel until the internal air pressure of the air pump returns to normal pressure, and determines whether the time to return to normal pressure is greater than the time threshold: if yes, replace the filter element of the first-stage filter closest to the unobstructed air intake channel and proceed to step S28; otherwise, proceed to step S28. S28. Determine whether the primary filter closest to the unobstructed air intake channel is the first-stage filter: If yes, after the air pump empties the internal air, proceed to step S3; if no, after the air pump empties the internal air, the on / off actuator connects the air intake channel connected to the previous primary filter, and then return to step S25. S3. Detect the gas to be tested, following these steps: S31. Connect the air inlet nozzle to the gas being tested; S32. Based on the type of gas being tested, determine whether the combination of quick-change gas sensor redundant detection modules installed in the mounting slots on each side meets the detection requirements: if yes, proceed to step S33; if no, replace the combination of quick-change gas sensor redundant detection modules corresponding to the gas being tested and proceed to step S33. S33. Depending on the type of gas being tested, the on / off actuator keeps one of the air intake channels corresponding to the gas being tested open until the air pump is filled with the gas being tested. S34. Based on the type of gas being tested, determine whether the gas inside the compressed air pump is needed: if yes, proceed to step S35; otherwise, proceed to step S37. S35, the on / off actuator cuts off the exhaust passage and all intake passages; S36. The air pump compresses the internal gas to be tested until the volume of the gas to be tested is compressed to the detection set value required for its detection. S37. The on / off actuator keeps the exhaust passage open until the air pump empties the gas being tested. During this process, all general gas sensor detection modules and quick-change gas sensor redundant detection modules detect the gas being tested.

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