CN217237730U - Gas sensor - Google Patents
Gas sensor Download PDFInfo
- Publication number
- CN217237730U CN217237730U CN202220418470.XU CN202220418470U CN217237730U CN 217237730 U CN217237730 U CN 217237730U CN 202220418470 U CN202220418470 U CN 202220418470U CN 217237730 U CN217237730 U CN 217237730U
- Authority
- CN
- China
- Prior art keywords
- gas
- signal detector
- chamber
- optical signal
- laser
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Landscapes
- Investigating Or Analysing Materials By Optical Means (AREA)
- Investigating Or Analyzing Materials By The Use Of Ultrasonic Waves (AREA)
Abstract
The utility model relates to a gas sensor, which comprises a photoacoustic cell, a laser, an acoustic signal detector, an optical signal detector and a host; the photoacoustic cell is provided with a gas chamber; the laser is fixedly connected with the photoacoustic cell, and the output end of the laser points to the gas chamber; the detection end of the acoustic signal detector is arranged in the air chamber and is used for acquiring an acoustic signal in the air chamber; the detection end of the optical signal detector is fixedly connected with the photoacoustic cell and is used for acquiring an optical signal of the laser after passing through the air chamber; the host is electrically connected with the acoustic signal detector and the optical signal detector, and a concentration value of the gas is obtained through the acoustic signal and the optical signal; the problem that the existing gas sensor is difficult to realize the gas concentration detection work with high precision and wide range is solved.
Description
Technical Field
The utility model relates to a gas sensor technical field especially relates to a gas sensor.
Background
A gas sensor is a device that converts information such as the composition and concentration of a gas into information that can be used by personnel, instruments, computers, and the like. Gas sensors specially used for detecting gas concentration are produced on the market, and the photoacoustic spectroscopy gas detection technology is mainly adopted.
For example, the invention patent with the application number of CN201810180468.1 discloses a PM2.5 concentration detection apparatus based on photoacoustic spectroscopy, in which the advantages of high sensitivity and fast response speed of an optical fiber F-P acoustic wave sensor based on a graphite fluoride alkyne vibrating membrane to acoustic waves and the characteristics of non-adhesion of PM2.5 to a super-hydrophobic coating on the inner wall of a photoacoustic cell are utilized to realize high sensitivity, high response speed and high stability detection of PM2.5 concentration.
However, the photoacoustic spectroscopy gas detection technique detects the gas concentration with a short plate, and particularly, when a high-concentration gas is detected by the photoacoustic spectroscopy gas detection technique, the detection accuracy is low, and it is difficult to realize a gas concentration detection work with a high accuracy in a wide range.
SUMMERY OF THE UTILITY MODEL
In view of the above, it is desirable to provide a gas sensor, which solves the problem that the existing gas sensor is difficult to perform a gas concentration detection operation with high accuracy and a wide range.
The utility model provides a gas sensor, which comprises a photoacoustic cell, a laser, an acoustic signal detector, an optical signal detector and a host; the photoacoustic cell is provided with a gas chamber; the laser is fixedly connected with the photoacoustic cell, and the output end of the laser points to the gas chamber; the detection end of the acoustic signal detector is arranged in the air chamber and is used for acquiring an acoustic signal in the air chamber; the detection end of the optical signal detector is fixedly connected with the photoacoustic cell and is used for acquiring an optical signal of the laser after passing through the air chamber; the host is electrically connected with the acoustic signal detector and the optical signal detector, and the concentration value of the gas is obtained through the acoustic signal and the optical signal.
Furthermore, the sound signal detector is a microphone, the microphone is fixedly arranged in the middle of the air chamber, and the microphone is electrically connected with the host.
Further, the optical signal detector is a photoresistor, the laser and the photoresistor are arranged on two sides of the air chamber, and the transmitting end of the laser points to the photoresistor.
Further, the host includes a control processing unit, and the control processing unit is electrically connected to the acoustic signal detector and the optical signal detector, and is configured to receive the electrical signal converted by the acoustic signal detector and the electrical signal converted by the optical signal detector.
Furthermore, the host computer still includes a pressure sensor and temperature sensor, pressure sensor with the temperature sensor all places in the air chamber, pressure sensor with the temperature sensor all with control processing unit electric connection.
Furthermore, the photoacoustic cell is of a symmetrical structure.
Furthermore, the photoacoustic cell is provided with an air inlet and an air outlet, and the air inlet and the air outlet are communicated with the air chamber.
Further, the air inlet with the gas outlet all via a surge chamber with the air chamber is linked together, the air chamber is rectangular pipeline form, the cross section of surge chamber is greater than the cross section of air chamber.
Furthermore, the photoacoustic cell further comprises two vacuum chambers, and the two vacuum chambers are oppositely arranged on two sides of the gas chamber.
Furthermore, grooves are formed in two sides, located on the air chamber, of the photoacoustic cell, a sealing plate is fixedly arranged in each groove, and a vacuum chamber is formed between the two sealing plates in each groove.
Compared with the prior art, the gas is sucked into the gas chamber, the gas chamber is sealed, the laser irradiates the gas in the gas chamber, the wavelength of the laser is made to cover the absorption spectrum of the gas in the gas chamber by controlling the drive current of the laser to periodically change in a certain range, the gas in the gas chamber absorbs the optical signal with periodically changing period to generate an acoustic signal, wherein, the sound signal is collected by the sound signal detector, the sound signal detector is suitable for the high-precision detection work of low-concentration gas, the optical signal is collected by the optical signal detector, the optical signal detector is suitable for the high-precision detection work of high-concentration gas, and converted into electric signals to be transmitted to a host computer, the host computer can obtain high-precision detection data in a wide range according to the two collected electric signals, and the collected data corresponding to the concentration range is selected as a determined value, so that the work of detecting the gas concentration with high precision and wide range can be realized.
Drawings
Fig. 1 is a schematic structural diagram of the gas sensor according to the present embodiment of the present invention.
Detailed Description
The following detailed description of the preferred embodiments of the invention, which is to be read in connection with the accompanying drawings, forms a part of this application, and together with the embodiments of the invention, serve to explain the principles of the invention and not to limit its scope.
As shown in fig. 1, a gas sensor in the present embodiment includes a photoacoustic cell 100, a laser 200, an acoustic signal detector 300, an optical signal detector 400, and a host 500; the photoacoustic cell 100 has a gas cell 110; the laser 200 is fixedly connected with the photoacoustic cell 100, and the output end of the laser 200 points to the gas chamber 110; the detection end of the acoustic signal detector 300 is arranged in the gas chamber 110 and is used for acquiring the acoustic signal in the gas chamber 110; the detection end of the optical signal detector 400 is fixedly connected with the laser 200 and is used for acquiring an optical signal of the laser 200 after passing through the gas chamber 110; the host 500 is electrically connected to the acoustic signal detector 300 and the optical signal detector 400, and obtains the concentration value of the gas through the acoustic signal and the optical signal.
Wherein gas is sucked into the gas chamber 110, the gas chamber 110 is closed, the gas in the gas chamber 110 is irradiated by the laser 200, the laser 200 wavelength covers the absorption spectrum of the gas in the gas cell 110 by controlling the drive current of the laser 200 to periodically change within a certain range, the light signal with periodically changing gas absorption in the gas cell 110 generates a sound signal, wherein, the sound signal is collected by the sound signal detector 300, the sound signal detector 300 is suitable for the high-precision detection work of low-concentration gas, the optical signal is collected by the optical signal detector 400, the optical signal detector 400 is suitable for the high-precision detection work of high-concentration gas, and converted into electric signals to be transmitted to the host 500, the host 500 can obtain a wide range of high-precision detection data according to the two collected electric signals, and the collected data corresponding to the concentration range is selected as a determination, as will be explained and illustrated in more detail below.
The photoacoustic cell 100 in this embodiment is a closed container filled with a gas sample to be detected. The photoacoustic cell 100 has a symmetrical structure, and the photoacoustic cell 100 has an air inlet 120 and an air outlet 130, and both the air inlet 120 and the air outlet 130 are communicated with the air chamber 110.
It should be noted that the air inlet 120 and the air outlet 130 can be connected or disconnected with each other from the outside through a valve or other structures, and in the detection process, both the air inlet 120 and the air outlet 130 need to be closed, so that a closed cavity is formed in the air chamber 110.
In order to make the detection result more accurate, in a preferred embodiment, the air inlet 120 and the air outlet 130 are both communicated with the air chamber 110 via a buffer chamber 140, the air chamber 110 is in the shape of an elongated pipe, and the cross section of the buffer chamber 140 is larger than that of the air chamber 110. The pumped gas can flow into the gas chamber 110 at a constant speed after being buffered by the buffer chamber 140, and the influence on the acoustic signal detector 300 and the optical signal detector 400 can be avoided.
In order to avoid the interference of the external sound to the gas cell 110, in a preferred embodiment, the photoacoustic cell 100 further includes two vacuum chambers 150, and the two vacuum chambers 150 are oppositely disposed at two sides of the gas cell 110.
The two sides of the photoacoustic cell 100 located in the gas chamber 110 in this embodiment are both provided with a groove, a sealing plate 160 is fixedly disposed in each groove, and a vacuum chamber 150 is formed between the two sealing plates 160 in each groove. In which the sealing plate 160 is a glass window. It is to be understood that the sealing plate may be a transparent plastic plate or the like having a light transmitting function.
Of course, in other preferred embodiments, the vacuum chamber 150 may be replaced by other structures, as long as the interference of the external sound to the air chamber 110 can be reduced.
In a preferred embodiment, the acoustic signal detector 300 is a microphone, the microphone is fixed in the middle of the air chamber 110, and the microphone is electrically connected to the host 500. The microphone can collect the optical signal of the gas absorption period change in the gas chamber 110 to generate the sound signal, and the gas in the low concentration range can be detected with high precision.
In a preferred embodiment, the optical signal detector 400 is a photo-resistor, the laser 200 and the photo-resistor are disposed at two sides of the gas cell 110, and the emitting end of the laser 200 is disposed toward the photo-resistor. The optical signal of the gas absorption period change in the gas chamber 110 can be collected through the optical surface resistor, and the gas in a high concentration range can be detected with high precision.
It should be noted that in other preferred embodiments, the light dependent resistor may also use other types of detectors to receive the light signal passing through the gas cell 110, as long as the light dependent resistor can receive the light signal, and the invention is not limited thereto.
In order to facilitate processing and selecting the signals collected by the acoustic signal detector 300 and the optical signal detector 400, in a preferred embodiment, the host 500 includes a control processing unit 510, and the control processing unit 510 is electrically connected to the acoustic signal detector 300 and the optical signal detector 400 and is configured to receive the electrical signal converted by the acoustic signal detector 300 and the electrical signal converted by the optical signal detector 400. It is understood that the control processing unit 510 in this embodiment is a chip for detecting current/voltage, and can be implemented by using, for example, MT9221/MT9223 chips. Of course, other types of chips may be used to receive the electrical signal converted by the acoustic signal detector 300 and the electrical signal converted by the optical signal detector 400.
In order to facilitate the control of the laser 200, in a preferred embodiment, the host 500 further includes a single chip, a laser driving circuit, an acoustic signal processing circuit, and an optical signal processing circuit, and the single chip is electrically connected to the laser 200 through the laser driving circuit and is used for controlling the laser 200 to operate.
In order to determine the concentration range of the gas, the host 500 further includes a pressure sensor 520 and a temperature sensor 530, the pressure sensor 520 and the temperature sensor 530 are both disposed in the gas chamber 110, and the pressure sensor 520 and the temperature sensor 530 are both electrically connected to the control processing unit 510 to determine the concentration range of the gas in the gas chamber 110. Specifically, the concentration value of the gas is positively correlated with the pressure value in the gas chamber 110 acquired by the pressure sensor 520 and the temperature value in the gas chamber 110 acquired by the temperature controller 530, and the concentration information demodulated by the acoustic signal detector 300 and the optical signal detector 400 is corrected according to the acquired pressure value and temperature value in the gas chamber 110, so as to obtain the accurate gas concentration.
Compared with the prior art: the gas is generated by sucking the gas into the gas cell 110, closing the gas cell 110, irradiating the gas inside the gas cell 110 by the laser 200, the laser 200 wavelength covers the absorption spectrum of the gas in the gas cell 110 by controlling the drive current of the laser 200 to periodically change within a certain range, the light signal with periodically changing gas absorption in the gas cell 110 generates a sound signal, wherein, the sound signal is collected by the sound signal detector 300, the sound signal detector 300 is suitable for the high-precision detection work of low-concentration gas, the optical signal is collected by the optical signal detector 400, the optical signal detector 400 is suitable for the high-precision detection work of high-concentration gas, and converted into electric signals to be transmitted to the host computer 500, the host computer 500 can obtain a wide range of high-precision detection data according to the two collected electric signals, and the collected data corresponding to the concentration range is selected as a determined value, so that the work of detecting the gas concentration with high precision and wide range can be realized.
The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention should be covered by the present invention.
Claims (10)
1. A gas sensor is characterized by comprising a photoacoustic cell, a laser, an acoustic signal detector, an optical signal detector and a host;
the photoacoustic cell is provided with a gas chamber;
the laser is fixedly connected with the photoacoustic cell, and the output end of the laser points to the gas chamber;
the detection end of the acoustic signal detector is arranged in the air chamber and is used for acquiring an acoustic signal in the air chamber;
the detection end of the optical signal detector is fixedly connected with the photoacoustic cell and is used for acquiring an optical signal of the laser after passing through the air chamber;
the host is electrically connected with the acoustic signal detector and the optical signal detector, and the concentration value of the gas is obtained through the acoustic signal and the optical signal.
2. The gas sensor according to claim 1, wherein the acoustic signal detector is a microphone, the microphone is fixedly disposed in a middle portion of the gas chamber, and the microphone is electrically connected to the host.
3. The gas sensor according to claim 1, wherein the optical signal detector is a photo-resistor, the laser and the photo-resistor are disposed at two sides of the gas chamber, and the emitting end of the laser is disposed toward the photo-resistor.
4. The gas sensor according to claim 1, wherein the host comprises a control processing unit electrically connected to the acoustic signal detector and the optical signal detector for receiving the electrical signal converted by the acoustic signal detector and the electrical signal converted by the optical signal detector.
5. The gas sensor according to claim 4, wherein the host further comprises a pressure sensor and a temperature sensor, the pressure sensor and the temperature sensor are both disposed in the gas chamber, and the pressure sensor and the temperature sensor are both electrically connected to the control processing unit.
6. The gas sensor of claim 1, wherein the photoacoustic cell is a symmetric structure.
7. The gas sensor of claim 1, wherein the photoacoustic cell has a gas inlet and a gas outlet, both of which are in communication with a gas cell.
8. The gas sensor according to claim 7, wherein the gas inlet and the gas outlet are both in communication with the gas chamber via a buffer chamber, the gas chamber being in the form of an elongate tube, the buffer chamber having a cross-section larger than the cross-section of the gas chamber.
9. The gas sensor of claim 1, wherein the photoacoustic cell further comprises two vacuum chambers, the two vacuum chambers being disposed opposite to each other on either side of the gas chamber.
10. The gas sensor according to claim 9, wherein the photoacoustic cell has grooves formed on both sides of the gas chamber, a sealing plate is fixedly disposed in each groove, and the vacuum chamber is formed between the two sealing plates in each groove.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220418470.XU CN217237730U (en) | 2022-02-28 | 2022-02-28 | Gas sensor |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202220418470.XU CN217237730U (en) | 2022-02-28 | 2022-02-28 | Gas sensor |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN217237730U true CN217237730U (en) | 2022-08-19 |
Family
ID=82840282
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202220418470.XU Active CN217237730U (en) | 2022-02-28 | 2022-02-28 | Gas sensor |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN217237730U (en) |
-
2022
- 2022-02-28 CN CN202220418470.XU patent/CN217237730U/en active Active
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| WO2017133045A1 (en) | Aerosol real time monitor | |
| CN110006837A (en) | A kind of NDIR gas sensor system and temperature and humidity compensation method | |
| CN103884672A (en) | SF6 gas decomposed product detection device and method based on photoacoustic spectrometry technology | |
| CN104251819A (en) | Photoacoustic spectrometry gas detection apparatus based on infrared light source | |
| CN110865121A (en) | Device and method for detecting hydrogen concentration in multi-component mixed gas | |
| CN112730264B (en) | Differential MEMS gas sensor | |
| CN100401041C (en) | Optical waveguide absorption gas sensor and measurement system | |
| CN105823749A (en) | Capacitor type infrared gas sensor based on MEMS and preparing method of capacitor type infrared gas sensor | |
| CN110763632A (en) | A Concentration Detection System of Dissolved Gas in Transformer Oil | |
| CN110940632A (en) | TDLAS-based methane gas concentration detection device and detection method | |
| CN217484253U (en) | Photoacoustic spectrum nitrogen dioxide analyzer based on laser diode | |
| CN217237730U (en) | Gas sensor | |
| JP5919895B2 (en) | Detector for infrared gas analyzer | |
| CN101825564B (en) | Optical detection method for continuously monitoring liquid concentration for a long time | |
| WO2022267555A1 (en) | Radial cavity quartz-enhanced photoacoustic spectrophone and gas detection device comprising same | |
| CN114509388A (en) | Gas sensor | |
| CN114813574A (en) | Differential photoacoustic spectrum gas concentration detection device based on dual-channel T-shaped photoacoustic cell | |
| CN206321568U (en) | A kind of Moisture in Lube Oil ＆ content detection device based on optofluidic technology | |
| CN211292561U (en) | A Concentration Detection System of Dissolved Gas in Transformer Oil | |
| CN112881299A (en) | Interference type all-fiber photoacoustic spectroscopy system based on passive tuning fork and detection method thereof | |
| CN115586138B (en) | Environmental engineering atmospheric pollution detection device | |
| CN116973282A (en) | Novel method for detecting PM2.5 concentration in air | |
| CN100419408C (en) | Infrared-ray gas analyser | |
| CN104596612A (en) | Method and device for detecting liquid level and liquid capacity | |
| CN113171655B (en) | Collection and detection integrated aerosol separator |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| GR01 | Patent grant | ||
| GR01 | Patent grant |