Portable electronic nose system

Abstract

The utility model belongs to the technical field of gas detection equipment, and particularly discloses a portable electronic nose system. According to the application, the circuit and the gas circuit are optimized in the aspect of hardware, so that the size and the weight of the whole equipment are reduced; in addition, a rechargeable lithium ion battery is adopted for power supply, wireless work can be carried out for more than 6 hours, and therefore portability is achieved. According to the application, various types of gas sensors are adopted, so that the system has specific response to various components in the complex gas, and the control circuit board analyzes the collected different electric signals, so that different gas components in the complex gas are effectively distinguished.

Description

Technical Field

[0001] This application belongs to the field of gas detection equipment technology, and more specifically, relates to a portable electronic nose system. Background Technology

[0002] With the acceleration of global industrialization and urbanization, air pollution has become a major global challenge. The emission of various harmful gases not only causes serious environmental damage but also poses a direct threat to human health. Therefore, the demand for monitoring and analyzing harmful gases is increasing, especially in fields such as industrial production, environmental protection, industrial safety, and health diagnostics.

[0003] Traditional gas detection techniques, such as gas chromatography and mass spectrometry, while highly accurate, typically require large, expensive equipment and are complex to operate. They necessitate specialized personnel for sample pretreatment and data analysis, making them unsuitable for rapid, on-site detection. Furthermore, these techniques are often specific to particular gases and struggle to simultaneously analyze multiple components within complex atmospheric gases. Utility Model Content

[0004] In view of the shortcomings of the prior art, the purpose of this application is to provide a portable electronic nose system, which aims to solve the problems of existing electronic noses being large in size, unsuitable for rapid on-site detection, and unable to analyze multiple components simultaneously.

[0005] To achieve the above objectives, this application provides a portable electronic nose system, comprising: a gas filter, a three-way solenoid valve, a first air chamber, a second air chamber, a third air chamber, a miniature mass flow meter, a sampling pump, a control circuit board, and a display unit;

[0006] The first chamber is equipped with a temperature and humidity sensor, the second chamber is equipped with a semiconductor sensor array, and the third chamber is equipped with an electrochemical sensor array.

[0007] The gas filter is provided with an inlet pipe and an outlet pipe, and the inlet pipe is connected to the environment being measured;

[0008] The three-way solenoid valve has two air inlets and one air outlet. The first air inlet is connected to the air outlet pipe of the gas filter, the second air inlet is connected to the calibration gas, and the air outlet is connected to the inlet of the first air chamber.

[0009] The first air chamber, the second air chamber, and the third air chamber are connected in series in the direction of gas flow;

[0010] The miniature mass flow meter is located between the third air chamber and the sampling pump, with its inlet connected to the outlet of the third air chamber and its outlet connected to the inlet of the sampling pump.

[0011] The control circuit board is electrically connected to the temperature and humidity sensor, the semiconductor sensor array, the electrochemical sensor array, the miniature mass flow meter, the sampling pump, the three-way solenoid valve, and the display unit, respectively.

[0012] Preferably, the temperature and humidity sensor uses an SHT30 chip or an SHT31 chip.

[0013] Preferably, the semiconductor sensor array is a TO-packaged gas sensor array, a MEMS gas sensor array, or a CMOS gas sensor array.

[0014] Preferably, the semiconductor sensor array contains 6-10 sensors.

[0015] Preferably, the electrochemical sensor array uses a 4-series packaged electrochemical sensor.

[0016] Preferably, the number of sensors in the electrochemical sensor array is 3-6.

[0017] Preferably, the control circuit board includes: an STM32 microcontroller, a multi-channel signal acquisition circuit, a signal preprocessing circuit, and a drive circuit;

[0018] One end of the multi-channel signal acquisition circuit is electrically connected to each sensor array and the miniature mass flow meter, and the other end is electrically connected to the STM32 microcontroller.

[0019] One end of the signal preprocessing circuit is electrically connected to the multi-channel signal acquisition circuit, and the other end is electrically connected to the STM32 microcontroller, used to amplify and condition the detection signal;

[0020] The drive circuit includes a relay and a frequency converter. One end of the relay is electrically connected to a three-way solenoid valve, and the other end is electrically connected to an STM32 microcontroller to control the opening and closing of the three-way solenoid valve. One end of the frequency converter is electrically connected to the sampling pump, and the other end is electrically connected to the STM32 microcontroller to adjust the power of the sampling pump.

[0021] The STM32 microcontroller communicates with external terminals via an Ethernet communication interface or a 4G wireless communication interface, and is connected to the display unit via URAT.

[0022] Preferably, the display unit is a configurable touchscreen.

[0023] Preferably, it also includes a power supply module for providing the required operating voltage for the entire circuit.

[0024] Preferably, the power module is a rechargeable lithium-ion battery.

[0025] Overall, the technical solutions conceived in this application have the following beneficial effects compared with the prior art:

[0026] This application proposes a portable electronic nose system. In terms of hardware, the circuitry and gas path are optimized, thereby reducing the overall size and weight of the device. Furthermore, this application uses a rechargeable lithium-ion battery for power, enabling wireless operation for over 6 hours, thus achieving portability. This application employs multiple types of gas sensors, allowing the system to respond specifically to various components in complex gases. The control circuit board analyzes the collected electrical signals, effectively distinguishing different gas components within complex gases. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of a portable electronic nose system provided in an embodiment of this application.

[0028] Figure 2 This is a schematic diagram of the control circuit board structure provided in the embodiment of this application.

[0029] In all the accompanying drawings, the same reference numerals are used to denote the same elements or structures, wherein:

[0030] 1 is a gas filter, 2 is a three-way solenoid valve, 3 is the first gas chamber, 4 is the second gas chamber, 5 is the third gas chamber, 6 is a miniature mass flow meter, 7 is a sampling pump, 8 is a control circuit board, and 9 is a display unit. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0032] The embodiments of this application are described below with reference to the accompanying drawings.

[0033] like Figure 1 As shown, this application proposes a portable electronic nose system, including: a gas filter 1, a three-way solenoid valve 2, a first air chamber 3, a second air chamber 4, a third air chamber 5, a miniature mass flow meter 6, a sampling pump 7, a control circuit board 8, and a display unit 9. Among them,

[0034] The gas filter 1 is equipped with an inlet pipe and an outlet pipe. The inlet pipe is connected to the environment being tested and is used to remove dust, particulate matter, and other solids from the air in the environment being tested, preventing blockage of the gas path. It can also remove special components, including but not limited to: water, water vapor, and redox gases, depending on the actual environmental requirements.

[0035] The three-way solenoid valve 2 has two air inlets and one air outlet. The first air inlet is connected to the air outlet pipe of the gas filter, the second air inlet is connected to the calibration gas, and the air outlet is connected to the inlet of the first gas chamber 3 to control the flow path of the gas.

[0036] The first air chamber 3, the second air chamber 4, and the third air chamber 5 are connected in series in the direction of gas flow, with the outlet of the former connected to the inlet of the latter.

[0037] The first air chamber 3 is equipped with a temperature and humidity sensor to collect ambient temperature and humidity.

[0038] The second gas chamber 4 is equipped with a semiconductor sensor array, which is used to collect the changes in electrical signals after the gas-sensitive material undergoes oxidation-reduction reactions with various gas components.

[0039] The third gas chamber 5 is equipped with an electrochemical sensor array, which is used to collect changes in electrical signals after the sensors react chemically with each gas component.

[0040] The miniature mass flow meter 6 is located between the third gas chamber 5 and the sampling pump 7. Its inlet is connected to the outlet of the third gas chamber 5, and its outlet is connected to the inlet of the sampling pump 7. It is used to detect the gas flow rate passing through the gas sensor. The gas flow rate directly affects the contact time and reaction degree between the sensor and the gas. In this embodiment, the miniature mass flow meter 6 is an FS4001.

[0041] The sampling pump 7 has adjustable power and is used to provide gas flow power to discharge exhaust gas into the environment being tested.

[0042] The control circuit board 8 is electrically connected to the temperature and humidity sensor, the semiconductor sensor array, and the electrochemical sensor array, respectively, to receive and analyze all collected electrical signals and generate analysis results for complex gases; it is also electrically connected to the miniature mass flow meter 6 and the sampling pump 7, respectively, to receive the detected gas flow rate and adjust the power of the sampling pump by adjusting the duty cycle of the PWM, thereby changing the gas flow rate until the detected flow rate reaches the set flow rate value; and it is electrically connected to the three-way solenoid valve 2 to control the opening and closing of the three-way solenoid valve 2.

[0043] The display unit 9 is electrically connected to the control circuit board 8 and is used to display the results of complex gas analysis.

[0044] In this application, the gas inlet pipeline consists of a gas filter, a three-way solenoid valve, a miniature mass flow meter, and a sampling pump to control the entry and exit of the gas to be tested (filtration, switching, and flow rate); the detection pipeline consists of three sensor chambers connected in series to detect the gas composition and convert the chemical signal into an electrical signal.

[0045] In this application, the calibration gas is a gas of known composition and concentration used to provide a standard reference signal for the electronic nose's sensors. Details regarding the use of the calibration gas to train the recognition model are prior art; see patent CN113804833A.

[0046] Preferably, the temperature and humidity sensor uses an SHT30 chip or an SHT31 chip.

[0047] Preferably, the semiconductor sensor array is a TO-packaged gas sensor array, a MEMS gas sensor array, or a CMOS gas sensor array. The array typically contains 6-10 semiconductor sensors; in this embodiment, it contains 8, which collect data on NO2, NH3, ethanol, formaldehyde, acetone, etc., in the air. The semiconductor gas sensor responds to many gases, albeit with varying degrees of responsivity. Subsequent algorithmic analysis identifies the different gas components.

[0048] Preferably, the electrochemical sensor array uses 4-series packaged electrochemical sensors. The array typically contains 3-6 electrochemical sensors; in this embodiment, it contains 4, which collect data on O2, VOCs, CO, NH3, H2S, SO2, and combustible gases in the air.

[0049] Preferably, the control circuit board includes: an STM32 microcontroller, a multi-channel signal acquisition circuit, a signal preprocessing circuit, and a drive circuit, wherein,

[0050] One end of the multi-channel signal acquisition circuit is electrically connected to each sensor array and the miniature mass flow meter, and the other end is electrically connected to the STM32 microcontroller.

[0051] One end of the signal preprocessing circuit is electrically connected to the multi-channel signal acquisition circuit, and the other end is electrically connected to the STM32 microcontroller, used to amplify and condition the detection signal;

[0052] The drive circuit includes a relay and a frequency converter. One end of the relay is electrically connected to a three-way solenoid valve, and the other end is electrically connected to an STM32 microcontroller to control the opening and closing of the three-way solenoid valve. One end of the frequency converter is electrically connected to the sampling pump, and the other end is electrically connected to the STM32 microcontroller to adjust the power of the sampling pump.

[0053] The STM32 microcontroller communicates with external terminals via an Ethernet communication interface or a 4G wireless communication interface, and is connected to the display unit via URAT.

[0054] The multi-channel signal acquisition circuit includes a low-internal-resistance analog switch, which is electrically connected to the STM32 microcontroller and is used to switch between different sampling channels.

[0055] The STM32 microcontroller adjusts the power of the sampling pump by adjusting the duty cycle of the PWM. This control method is existing technology, see patent CN105911228A.

[0056] The STM32 microcontroller is equipped with a recognition algorithm to identify electrical signals collected from multiple gas sensors of different types. The recognition algorithm includes, but is not limited to, support vector machine or neural network recognition algorithms, see patent CN109724645A.

[0057] Preferably, the display unit is a configurable touchscreen, which integrates a touchscreen and human-computer interface software to realize human-computer interaction and visual operation. Through the touchscreen, users can directly operate the screen using their fingers or a stylus.

[0058] Preferably, the portable electronic nose system further includes a power module for providing the required operating voltage for the entire circuit.

[0059] Preferably, the battery used is a rechargeable lithium-ion battery.

[0060] It should be understood that expressions such as “comprising” and “may include” used in this application indicate the existence of the disclosed functions, operations, or constituent elements, and do not limit one or more additional functions, operations, and constituent elements. In this application, terms such as “comprising” and / or “having” are to be interpreted as indicating a particular characteristic, number, operation, constituent element, component, or combination thereof, but not to exclude the existence or possibility of adding one or more other characteristics, numbers, operations, constituent elements, components, or combinations thereof.

[0061] Furthermore, in this application, the expression "and / or" includes any and all combinations of the associated listed words. For example, the expression "A and / or B" may include A, may include B, or may include both A and B.

[0062] In the description of the embodiments of this application, it should be noted that, unless otherwise explicitly specified and limited, the term "connection" should be interpreted broadly. For example, "connection" can be a detachable connection or a non-detachable connection; it can be a direct connection or an indirect connection through an intermediate medium. The directional terms mentioned in the embodiments of this application, such as "top," "bottom," "inner," "outer," "left," and "right," are only for reference to the directions in the accompanying drawings. Therefore, the directional terms used are for better and clearer explanation and understanding of the embodiments of this application, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the embodiments of this application.

[0063] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A portable electronic nose system, characterized in that The utility model relates to a kind of gas sampling device, including: Gas filter, three-way electromagnetic valve, first gas chamber, second gas chamber, third gas chamber, micro mass flow meter, sampling pump, control circuit board and display unit; The first gas chamber is equipped with temperature and humidity sensor, the second gas chamber is equipped with semiconductor sensor array, and the third gas chamber is equipped with electrochemical sensor array; The gas filter is provided with air inlet pipe and air outlet pipe, and the air inlet pipe is communicated with the environment to be measured; The three-way electromagnetic valve is provided with two air inlets and one air outlet, the first air inlet is connected to the air outlet pipe of the gas filter, the second air inlet is communicated with calibration gas, and the air outlet is connected to the inlet of the first gas chamber; The first gas chamber, the second gas chamber and the third gas chamber are connected in series in the direction of gas flow; The micro mass flow meter is arranged between the third gas chamber and the sampling pump, and the air inlet thereof is connected to the outlet of the third gas chamber, and the air outlet thereof is connected to the inlet of the sampling pump; The control circuit board is electrically connected with the temperature and humidity sensor, the semiconductor sensor array, the electrochemical sensor array, the micro mass flow meter, the sampling pump, the three-way electromagnetic valve and the display unit, respectively.

2. The portable electronic nose system of claim 1, wherein, The temperature and humidity sensor uses SHT30 chip or SHT31 chip.

3. The portable electronic nose system of claim 1, wherein, The semiconductor sensor array uses TO packaged gas sensor array, MEMS gas sensor array or CMOS gas sensor array.

4. The portable electronic nose system of claim 3, wherein, The number of sensors in the semiconductor sensor array is 6-10.

5. The portable electronic nose system of claim 1, wherein, The electrochemical sensor array uses 4 series packaged electrochemical sensor.

6. The portable electronic nose system of claim 5, wherein, The number of sensors in the electrochemical sensor array is 3-6.

7. The portable electronic nose system of claim 1, wherein, The control circuit board includes STM32 single-chip microcomputer, multi-channel signal acquisition circuit, signal preprocessing circuit and driving circuit. One end of the multi-channel signal acquisition circuit is electrically connected with each sensor array and the micro mass flow meter, and the other end is electrically connected with the STM32 single-chip microcomputer. One end of the signal preprocessing circuit is electrically connected with the multi-channel signal acquisition circuit, and the other end is electrically connected with the STM32 single-chip microcomputer, for amplifying and signal conditioning the detection signal. The driving circuit includes a relay and a frequency converter, one end of the relay is electrically connected with the three-way electromagnetic valve, the other end is electrically connected with the STM32 single-chip microcomputer, for controlling the on-off of the three-way electromagnetic valve, one end of the frequency converter is electrically connected with the sampling pump, the other end is electrically connected with the STM32 single-chip microcomputer, for adjusting the power of the sampling pump. The STM32 single-chip microcomputer is connected with external terminal through Ethernet communication interface or 4G wireless communication interface, and is connected with the display unit through URAT.

8. The portable electronic nose system of claim 1, wherein, The display unit is a configuration touch screen.

9. The portable electronic nose system of claim 1, wherein, It also includes a power module for providing the required operating voltage for the entire circuit.

10. The portable electronic nose system of claim 9, wherein, The power module is a rechargeable lithium ion battery.

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