CN112461778A - High-precision multi-channel combustible gas detector - Google Patents
High-precision multi-channel combustible gas detector Download PDFInfo
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- CN112461778A CN112461778A CN202011239850.9A CN202011239850A CN112461778A CN 112461778 A CN112461778 A CN 112461778A CN 202011239850 A CN202011239850 A CN 202011239850A CN 112461778 A CN112461778 A CN 112461778A
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- 239000007789 gas Substances 0.000 claims abstract description 75
- 238000010521 absorption reaction Methods 0.000 claims abstract description 26
- 230000003287 optical effect Effects 0.000 claims abstract description 20
- 238000006243 chemical reaction Methods 0.000 claims abstract description 13
- 230000000694 effects Effects 0.000 claims abstract description 6
- 230000003321 amplification Effects 0.000 claims abstract description 5
- 238000003199 nucleic acid amplification method Methods 0.000 claims abstract description 5
- 239000000428 dust Substances 0.000 claims abstract description 4
- VNWKTOKETHGBQD-UHFFFAOYSA-N methane Chemical compound C VNWKTOKETHGBQD-UHFFFAOYSA-N 0.000 description 6
- 238000000034 method Methods 0.000 description 3
- 230000002238 attenuated effect Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- 238000000862 absorption spectrum Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- KPUWHANPEXNPJT-UHFFFAOYSA-N disiloxane Chemical compound [SiH3]O[SiH3] KPUWHANPEXNPJT-UHFFFAOYSA-N 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/17—Systems in which incident light is modified in accordance with the properties of the material investigated
- G01N21/25—Colour; Spectral properties, i.e. comparison of effect of material on the light at two or more different wavelengths or wavelength bands
- G01N21/31—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry
- G01N21/35—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light
- G01N21/3504—Investigating relative effect of material at wavelengths characteristic of specific elements or molecules, e.g. atomic absorption spectrometry using infrared light for analysing gases, e.g. multi-gas analysis
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N21/00—Investigating or analysing materials by the use of optical means, i.e. using sub-millimetre waves, infrared, visible or ultraviolet light
- G01N21/01—Arrangements or apparatus for facilitating the optical investigation
- G01N2021/0106—General arrangement of respective parts
- G01N2021/0112—Apparatus in one mechanical, optical or electronic block
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Abstract
The invention discloses a high-precision multi-channel combustible gas detector, which comprises an infrared emission tube, a gas absorption optical cavity, a photoelectric conversion circuit, an operational amplification circuit and a signal acquisition circuit, wherein the infrared emission tube is connected with the gas absorption optical cavity; the infrared transmitting tube emits infrared light, the infrared light has an absorption effect on corresponding combustible gas through the gas absorption light cavity, the light beam is divided into three beams of light by the aid of the two spectroscopes after passing through the gas absorption light cavity, the light beam is divided into two channels, the different combustible gases are subjected to photoelectric conversion through the photoelectric conversion circuit, the two channels eliminate light source shaking and dust interference through one reference light path, generated electric signals are amplified by the operation amplifier and then transmitted to the signal acquisition circuit, and the single chip microcomputer compares acquired data with a concentration threshold value to trigger an alarm signal. The combustible gas detector is not required to be preheated, is not easy to be poisoned, and can simultaneously detect the concentration of the components of the mixed combustible gas.
Description
Technical Field
The invention relates to the field of combustible gas detectors, which detect the concentration of mixed gas by utilizing different gases with different absorption spectra to infrared radiation and correlation of absorption intensity and gas concentration, in particular to a high-precision multi-channel combustible gas detector.
Background
In recent years, people pay more and more attention to household gas safety and environmental pollution, and a single gas detector is not enough to meet the requirements of various places. Most of the existing combustible gas detectors adopt a plurality of gas sensors, and the mode has single function, can only measure one combustible gas and cannot meet the requirement of measuring a plurality of gases harmful to human bodies. The detector using the gas sensor needs to be preheated before use, the detector is required to send out an alarm signal within 5min of power restoration according to standards, and the concentration of combustible gas cannot be detected in real time due to overlong preheating time, so that danger is caused. In addition, the anti-poisoning performance of the currently used combustible gas detector is not good, and the detector has the concentration of 1% LEL of combustible gas and the concentration of (10 +/-3) multiplied by 10 of hexamethyl silyl ether steam-6The (volume fraction) mixed gas environment works for 40min, and the detector does not send out an alarm signal and a fault signal in the period. The interference of other gases to the detector easily causes the detector to work inaccurately, and these numerous factors lead to the combustible gas detector measuring accuracy low, fragile. And the method of using infrared absorption can effectively avoid the sensor from interfering due to other factors.
Disclosure of Invention
The gas detector aims to solve the problems that an existing combustible gas detector needs to be preheated, is single in measuring function and is easy to be interfered by other gases. The invention aims to provide a combustible gas detector which utilizes different gases to have different absorption intensities on infrared radiation and simultaneously measures various gases such as methane, carbon monoxide and the like.
The technical scheme adopted by the invention for solving the problems is as follows:
a high-precision multi-channel combustible gas detector comprises an infrared emission tube, a gas absorption optical cavity, a photoelectric conversion circuit, an operational amplification circuit and a signal acquisition circuit;
the infrared transmitting tube emits infrared light, the infrared light has an absorption effect on corresponding combustible gas through the gas absorption light cavity, the light beam is divided into three beams of light by the aid of the two spectroscopes after passing through the gas absorption light cavity, the light beam is divided into two channels, the different combustible gases are subjected to photoelectric conversion through the photoelectric conversion circuit, the two channels eliminate light source shaking and dust interference through one reference light path, generated electric signals are amplified by the operation amplifier and then transmitted to the signal acquisition circuit, and the single chip microcomputer compares acquired data with a concentration threshold value to trigger an alarm signal.
The further technology of the invention is as follows:
the optimal alarm threshold value is set through the key, the channel judges the concentration of the gas, the electric signal generated by the reference light path is used for detecting whether the received light intensity changes, the test precision is influenced when the received light intensity is too low, and the PWM wave of the drive of the light source is adjusted.
Preferably, the gas absorption optical cavity is of a cylindrical structure, an incident light source is arranged on the side wall of the cylinder, three reflectors are arranged on the inner wall of the cylinder, infrared light passes through the optical cavity provided with the three reflectors, the angle of the incident light source is adjusted to be obliquely upwards incident into the optical cavity from the bottom, multiple reflection is carried out in the centers of the three reflectors, and finally the infrared light is obliquely upwards emitted from the top of the optical cavity.
Preferably, the three reflective mirrors are in a regular triangle layout.
The invention has the beneficial effects that:
the combustible gas detector is not required to be preheated, is not easy to be poisoned, and can simultaneously detect the concentration of the components of the mixed combustible gas.
Drawings
FIG. 1 is a schematic diagram of the present invention;
fig. 2 is a diagram of a gas absorbing optical cavity.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As shown in FIG. 1, a high-precision multi-channel combustible gas detector comprises an infrared emission tube, a gas absorption optical cavity, a photoelectric conversion circuit, an operational amplification circuit and a signal acquisition circuit;
the infrared transmitting tube emits infrared light, the infrared light has an absorption effect on corresponding combustible gas through the gas absorption light cavity, the light beam is divided into three beams of light by the aid of the two spectroscopes after passing through the gas absorption light cavity, the light beam is divided into two channels, the different combustible gases are subjected to photoelectric conversion through the photoelectric conversion circuit, the two channels eliminate light source shaking and dust interference through one reference light path, generated electric signals are amplified by the operation amplifier and then transmitted to the signal acquisition circuit, and the single chip microcomputer compares acquired data with a concentration threshold value to trigger an alarm signal.
Whether the concentration of gas is judged through the button setting warning threshold value and passageway, the signal of telecommunication that the reference light path produced is used for detecting simultaneously whether the light intensity of receiving changes, can influence the measuring accuracy when the light intensity of receiving is low, adjusts the driven PWM ripples of light source, can keep receiving a stable received signal, actually is the process of a negative feedback.
The gas absorption light cavity is of a cylindrical structure, an incident light source is arranged on the side wall of the cylinder, three reflectors are arranged on the inner wall of the cylinder, infrared light penetrates through the light cavity provided with the three reflectors, the angle of the incident light source is adjusted to be obliquely upwards incident into the light cavity from the bottom, multiple reflection is carried out in the centers of the three reflectors, and finally the infrared light is obliquely upwards emitted from the top of the light cavity.
The three reflectors are in regular triangle layout.
An optical path part:
since the infrared absorption peaks of CO and CH4 are respectively 4.5um and 3.46um, an infrared emission tube with the wavelength of infrared light reaching 5um is selected as a light source, the infrared light source is driven by using a PWM mode, an alternating current electric signal can be obtained after conversion of a photoelectric sensor, the signal can be extracted relatively simply when the signal is interfered, the infrared light passes through an optical cavity provided with three reflectors as shown in figure 2, the angle of an incident light source is adjusted to be obliquely emitted into the optical cavity from the bottom, multiple reflection is carried out in the centers of the three reflectors, and finally the infrared light is obliquely emitted from the top of the optical cavity. The design increases the optical path of infrared light, and utilizes the circular space to the maximum extent, so that the mixed gas is fully absorbed in the limited space. The smaller the incident angle of the incident light is, the more times the infrared light is reflected, and the more sensitive the detection is. The traditional white cell air chamber uses concave lenses, only a few times of reflection can be carried out between the lenses, and the lenses need to be added if the optical path is increased, so that the volume of the air chamber is increased. The combustible gas detector is generally small in size, and the size of a product is influenced inevitably due to the fact that the optical cavity is too large in design. The optical cavity design of fig. 2 is adopted, the effect of increasing the optical path by multiple reflections is achieved by utilizing the height of the reflector and the angle of incident light, and no dead angle exists when the circular structure is used for receiving gas. When mixed combustible gas passes through the gas chamber, CO and CH4 have an absorption effect on infrared light, infrared light with wavelengths of 4.5um and 3.46um can be attenuated due to gas absorption according to the Lambert law, an infrared light beam V with attenuated light intensity is divided into two infrared light beams V1 and V2 with equal light intensity through the spectroscope, and the V1 is divided into two infrared light beams V3 and V3' with equal light intensity through the spectroscope. V2, V3 obtain the infrared light after attenuating through the filter of wavelength 4.5um and 3.46um, the infrared light after attenuating passes photodetector and converts the optical signal into the electric signal S1, S2 of alternating current, V3' is regarded as the reference light path of V3, select the wavelength to be near 4.5um and 3.46um, the filter that does not absorb the wavelength in other gases, the infrared light obtained in this way will not receive the interference of other gases, the electric signal that produces through the photodetector is the difference that S3 and S1 and S3 are the electric signal that CO concentration change produced, the difference that S63 2 and double S3 are the electric signal that CH4 concentration change produced, two channels do not interfere with each other, and do not receive light source shake and the interference of other gases.
A circuit part:
the triode is used for driving the infrared transmitting tube, the current of the base electrode is controlled through the PWM wave, so that the situation that a small direct current small signal is generated and is submerged in noise can be prevented, the infrared light modulated through the PWM wave obtains a small alternating current signal with certain frequency through the photoelectric sensor, the small alternating current signal generated by the photoelectric detector is amplified into a signal which can be collected by the single chip microcomputer through filtering and operational amplification, the obtained concentration of CO and CH4 is compared with a set alarm threshold value, and the function of detecting and alarming the mixed combustible gas is achieved. The electric signal that the reference light path produced is used for detecting whether the light intensity of receiving changes simultaneously, can influence the measuring accuracy when the light intensity of receiving is too low, adjusts the frequency of the PWM frequency of the drive of light source this moment, increases the luminous intensity of light source, can keep what received is a stable received signal, is actually a process of negative feedback. Thereby realizing a high-precision multi-channel combustible gas detector.
The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, which are described in the specification and illustrated only to illustrate the principle of the present invention, but that various changes and modifications may be made therein without departing from the spirit and scope of the present invention, which fall within the scope of the invention as claimed. The scope of the invention is defined by the appended claims and equivalents thereof.
Claims (4)
1. A high-precision multi-channel combustible gas detector is characterized in that: the device comprises an infrared emission tube, a gas absorption optical cavity, a photoelectric conversion circuit, an operational amplification circuit and a signal acquisition circuit;
the infrared transmitting tube emits infrared light, the infrared light has an absorption effect on corresponding combustible gas through the gas absorption light cavity, the light beam is divided into three beams of light by the aid of the two spectroscopes after passing through the gas absorption light cavity, the light beam is divided into two channels, the different combustible gases are subjected to photoelectric conversion through the photoelectric conversion circuit, the two channels eliminate light source shaking and dust interference through one reference light path, generated electric signals are amplified by the operation amplifier and then transmitted to the signal acquisition circuit, and the single chip microcomputer compares acquired data with a concentration threshold value to trigger an alarm signal.
2. A high accuracy multi-channel flammable gas sensor as claimed in claim 1 wherein: whether the concentration of gas is judged through the button setting warning threshold value and passageway, the signal of telecommunication that the reference light path produced is used for detecting simultaneously whether the light intensity of receiving changes, can influence the measuring accuracy when the light intensity of receiving is low, adjusts the driven PWM ripples of light source.
3. A high accuracy multi-channel flammable gas sensor as claimed in claim 1 wherein: the gas absorption light cavity is of a cylindrical structure, an incident light source is arranged on the side wall of the cylinder, three reflectors are arranged on the inner wall of the cylinder, infrared light penetrates through the light cavity provided with the three reflectors, the angle of the incident light source is adjusted to be obliquely upwards incident into the light cavity from the bottom, multiple reflection is carried out in the centers of the three reflectors, and finally the infrared light is obliquely upwards emitted from the top of the light cavity.
4. A high accuracy multi-channel flammable gas sensor as claimed in claim 2 wherein: the three reflectors are in regular triangle layout.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202011239850.9A CN112461778A (en) | 2020-11-09 | 2020-11-09 | High-precision multi-channel combustible gas detector |
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| CN202011239850.9A CN112461778A (en) | 2020-11-09 | 2020-11-09 | High-precision multi-channel combustible gas detector |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114112971A (en) * | 2021-11-23 | 2022-03-01 | 电子科技大学长三角研究院(湖州) | Infrared light detection method for rapidly detecting industrial emission formaldehyde |
| CN115112593A (en) * | 2022-05-25 | 2022-09-27 | 中国船舶重工集团公司第七0三研究所 | Multichannel redundant combustible gas concentration detection method |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1195215C (en) * | 2003-07-30 | 2005-03-30 | 哈尔滨工业大学 | Method for simutaneously measuring two kinds of gases by using one diode-laser device |
| CN101498665A (en) * | 2009-02-27 | 2009-08-05 | 哈尔滨工业大学 | Sulphur dioxide gas concentration detection apparatus based on associated spectrum technology |
| CN103822893A (en) * | 2014-02-28 | 2014-05-28 | 江苏物联网研究发展中心 | NDIR (Non-Dispersive Infra-Red) gas sensor |
| CN204044064U (en) * | 2014-08-21 | 2014-12-24 | 华北电力大学（保定） | Detect office in oil based on terahertz time-domain spectroscopic technology and put the sample cell of failure gas |
| CN106404705A (en) * | 2016-12-15 | 2017-02-15 | 电子科技大学 | High-precision infrared multi-gas detection device |
-
2020
- 2020-11-09 CN CN202011239850.9A patent/CN112461778A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1195215C (en) * | 2003-07-30 | 2005-03-30 | 哈尔滨工业大学 | Method for simutaneously measuring two kinds of gases by using one diode-laser device |
| CN101498665A (en) * | 2009-02-27 | 2009-08-05 | 哈尔滨工业大学 | Sulphur dioxide gas concentration detection apparatus based on associated spectrum technology |
| CN103822893A (en) * | 2014-02-28 | 2014-05-28 | 江苏物联网研究发展中心 | NDIR (Non-Dispersive Infra-Red) gas sensor |
| CN204044064U (en) * | 2014-08-21 | 2014-12-24 | 华北电力大学（保定） | Detect office in oil based on terahertz time-domain spectroscopic technology and put the sample cell of failure gas |
| CN106404705A (en) * | 2016-12-15 | 2017-02-15 | 电子科技大学 | High-precision infrared multi-gas detection device |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114112971A (en) * | 2021-11-23 | 2022-03-01 | 电子科技大学长三角研究院(湖州) | Infrared light detection method for rapidly detecting industrial emission formaldehyde |
| CN115112593A (en) * | 2022-05-25 | 2022-09-27 | 中国船舶重工集团公司第七0三研究所 | Multichannel redundant combustible gas concentration detection method |
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Application publication date: 20210309 |