CN113156054A - Gas detection circuit and gas detector - Google Patents
Gas detection circuit and gas detector Download PDFInfo
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- CN113156054A CN113156054A CN202011575437.XA CN202011575437A CN113156054A CN 113156054 A CN113156054 A CN 113156054A CN 202011575437 A CN202011575437 A CN 202011575437A CN 113156054 A CN113156054 A CN 113156054A
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- 238000001514 detection method Methods 0.000 title claims abstract description 22
- 239000007789 gas Substances 0.000 claims abstract description 59
- 238000012545 processing Methods 0.000 claims abstract description 42
- 231100000331 toxic Toxicity 0.000 claims abstract description 10
- 230000002588 toxic effect Effects 0.000 claims abstract description 10
- 239000003990 capacitor Substances 0.000 claims description 22
- 230000000007 visual effect Effects 0.000 claims description 4
- 230000005540 biological transmission Effects 0.000 claims description 3
- 238000000034 method Methods 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 5
- 230000007850 degeneration Effects 0.000 description 2
- 210000005069 ears Anatomy 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 description 1
- RWSOTUBLDIXVET-UHFFFAOYSA-N Dihydrogen sulfide Chemical compound S RWSOTUBLDIXVET-UHFFFAOYSA-N 0.000 description 1
- VGGSQFUCUMXWEO-UHFFFAOYSA-N Ethene Chemical compound C=C VGGSQFUCUMXWEO-UHFFFAOYSA-N 0.000 description 1
- 239000005977 Ethylene Substances 0.000 description 1
- 101100001471 Schizosaccharomyces pombe (strain 972 / ATCC 24843) alm1 gene Proteins 0.000 description 1
- 206010039740 Screaming Diseases 0.000 description 1
- 206010040007 Sense of oppression Diseases 0.000 description 1
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 description 1
- 229910002091 carbon monoxide Inorganic materials 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- LSNXEANQILECTB-UHFFFAOYSA-N formaldehyde;methane Chemical compound C.O=C LSNXEANQILECTB-UHFFFAOYSA-N 0.000 description 1
- 229910000037 hydrogen sulfide Inorganic materials 0.000 description 1
- 238000005272 metallurgy Methods 0.000 description 1
- 238000005065 mining Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000012544 monitoring process Methods 0.000 description 1
- 239000001301 oxygen Substances 0.000 description 1
- 229910052760 oxygen Inorganic materials 0.000 description 1
- 239000000126 substance Substances 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
- G01N33/00—Investigating or analysing materials by specific methods not covered by groups G01N1/00 - G01N31/00
- G01N33/0004—Gaseous mixtures, e.g. polluted air
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N15/00—Investigating characteristics of particles; Investigating permeability, pore-volume or surface-area of porous materials
- G01N15/06—Investigating concentration of particle suspensions
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- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B21/00—Alarms responsive to a single specified undesired or abnormal condition and not otherwise provided for
- G08B21/02—Alarms for ensuring the safety of persons
- G08B21/12—Alarms for ensuring the safety of persons responsive to undesired emission of substances, e.g. pollution alarms
- G08B21/14—Toxic gas alarms
-
- G—PHYSICS
- G08—SIGNALLING
- G08B—SIGNALLING OR CALLING SYSTEMS; ORDER TELEGRAPHS; ALARM SYSTEMS
- G08B7/00—Signalling systems according to more than one of groups G08B3/00 - G08B6/00; Personal calling systems according to more than one of groups G08B3/00 - G08B6/00
- G08B7/06—Signalling systems according to more than one of groups G08B3/00 - G08B6/00; Personal calling systems according to more than one of groups G08B3/00 - G08B6/00 using electric transmission, e.g. involving audible and visible signalling through the use of sound and light sources
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- Chemical & Material Sciences (AREA)
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- General Health & Medical Sciences (AREA)
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- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Pathology (AREA)
- Biochemistry (AREA)
- Immunology (AREA)
- Analytical Chemistry (AREA)
- Toxicology (AREA)
- Business, Economics & Management (AREA)
- Environmental & Geological Engineering (AREA)
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- Emergency Management (AREA)
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- Food Science & Technology (AREA)
- Medicinal Chemistry (AREA)
- Emergency Alarm Devices (AREA)
- Investigating Or Analyzing Materials By The Use Of Electric Means (AREA)
Abstract
The invention relates to the technical field of gas detection, in particular to a gas detection circuit and a gas detector, wherein the circuit comprises a gas sensor, a signal processing and compensating circuit, a DSP (digital signal processor) data processing circuit, a strong light alarm circuit, a strong sound alarm circuit, a display and output circuit and a public power supply circuit, the gas sensor is used for converting toxic and harmful gases in the atmospheric environment into proportional electric signals, the signal processing and compensating circuit is used for amplifying the weak electric signals output by the sensor to the amplitude that other circuits can process, and the DSP data processing circuit carries out corresponding processing on the signals sent by the signal processing and compensating circuit and sends the signals to the display and output circuit; the strong light alarm circuit is used for driving the strong light source to emit light; the strong sound alarm circuit is used for driving a strong sound source to sound; the display and output circuit is used for visually displaying the atmospheric data and other information; the power supply circuit is used for supplying power to each circuit system. The circuit of the invention has simple structure and low cost.
Description
Technical Field
The invention relates to the technical field of gas detection, in particular to a gas detection circuit and a gas detector.
Background
At present, the haze pollution problem is increasingly prominent. Under the large background of environmental management and ecological restoration, a large amount of detection and monitoring of various harmful gases are needed. When the concentration of the detected toxic and harmful gas reaches a set ratio, the device automatically reminds people on site through ear-piercing high-decibel screaming and strong eye-piercing red light, and the toxic and harmful gas exceeds the standard and is dangerous, and the people need to be evacuated or treated immediately. At present, the gas detector with the audible and visual alarm on the market has a complex circuit structure and higher cost.
Disclosure of Invention
The invention aims to provide a gas detection circuit with an acousto-optic alarm function. The aim is to simplify the complexity of the current circuit and to make the circuit more stable and less prone to failure.
The invention is realized by the following steps: a gas detection circuit comprises a gas sensor, a signal processing and compensating circuit, a DSP data processing circuit, a strong light alarm circuit, a strong sound alarm circuit, a display and output circuit and a public power supply circuit, wherein the gas sensor is used for converting toxic and harmful gases in the atmospheric environment into proportional electric signals, the signal processing and compensating circuit is used for amplifying weak electric signals output by the sensor to the amplitude of other circuits capable of being processed and processing, and performing corresponding circuit compensation to compensate distortion and loss of signals in the transmission process; the DSP data processing circuit carries out corresponding processing on the signals sent by the signal processing and compensating circuit and sends the processed signals to the display and output circuit; the strong light alarm circuit is used for driving the strong light source to emit light; the strong sound alarm circuit is used for driving a strong sound source to sound; the display and output circuit is used for visually displaying the atmospheric data and other information; the power supply circuit is used for supplying power to each circuit system; the strong light alarm circuit comprises a resistor R22 and a resistor R23 which are arranged in parallel, wherein the resistor R22 and the resistor R23 are both connected with a power supply end of the DSP data processing circuit, the other end of the resistor R22 is connected with a collector C of a switch tube Q5 through a concurrent light power supply, the other end of the resistor R23 is connected with a collector of a switch tube Q5 through a capacitor C25, a capacitor C26 and a light-emitting power supply which are sequentially connected, the other ends of the capacitor C25 and the capacitor C26 are respectively grounded, an emitter of the switch tube Q5 is grounded, and a base of the switch tube Q5 is connected with the DSP data processing circuit through a resistor R24.
Preferably, the loud alarm circuit comprises a loudspeaker, one end of the loudspeaker is connected with the resistor R2, the other end of the loudspeaker is connected with the collector electrode of the switch tube Q2, the emitter stage of the switch tube is grounded, and the base stage is connected with the DSP data processing circuit through the resistor R3.
Preferably, the light-emitting power source is a high-power LED visible strong light source, and the strong light sources are 1-4 parallel strong light sources. .
Preferably, the loudspeaker is a KHz/120dB strong sound source.
The invention also provides a gas detector which has an acousto-optic alarm function and comprises the gas detection circuit.
By adopting the technical scheme provided by the invention, the circuit is ingenious and stable, the structure is simple, the cost is low, and the practicability is high.
Drawings
FIG. 1 is a block diagram of a gas detection circuit according to an embodiment of the present invention;
FIG. 2 is a schematic diagram of a signal processing and compensation circuit in a gas detection circuit according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a strong light alarm circuit in a gas detection circuit according to an embodiment of the present invention;
FIG. 4 is a schematic diagram of a strong sound alarm circuit in a gas detection circuit according to an embodiment of the present invention;
fig. 5 is a schematic diagram of a DSP data processing circuit in the gas detection circuit according to the embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention will be described in further detail with reference to fig. 1 and an embodiment. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
The gas detection circuit provided by the invention comprises a gas sensor 1, a signal processing and compensating circuit 2, a DSP data processing circuit 3, a strong light alarm circuit 5, a strong sound alarm circuit 4, a display and output circuit 6 and a common power supply circuit 7, wherein the gas sensor 1 is an electrochemical sensor with high sensitivity and low power consumption. The sensor has the characteristics of high sensitivity, low power consumption, small volume, moderate price and the like, and can convert toxic and harmful gases in the atmospheric environment into proportional electric signals. The signal processing and compensating circuit 2 is used for amplifying a weak electric signal output by the sensor to the amplitude which can be processed by other circuits, performing corresponding circuit compensation and making up distortion and loss of the signal in the transmission process, the signal processing and compensating circuit 2 comprises a gas sensor biasing circuit and a gas sensor arithmetic circuit, the gas sensor biasing circuit is connected with a positive bias voltage end CE and a negative bias voltage end RE of the gas sensor, the gas sensor arithmetic circuit is connected with a third signal output end of the gas sensor, and a fourth signal output end of the gas sensor is grounded. The gas sensor operational circuit comprises a fourth resistor R4, a fifth resistor R5, an eighth resistor R8, a third capacitor C3, a second operational amplifier U2A and a third operational amplifier U2B, wherein one end of the fourth resistor R4 is connected with a third signal output end of the gas sensor, the other end of the fourth resistor R4 is connected with a non-inverting input end of the second operational amplifier U2A, an inverting input end of the second operational amplifier U2A is grounded, a signal output end of the second operational amplifier U2A is connected with an eighth resistor R8, the other end of the eighth resistor R8 is connected with an inverting input end of the third operational amplifier, a non-inverting input end and an output end of the eighth resistor R8 are electrically connected, and two ends of the third capacitor C3 and the fifth resistor R5 are respectively connected with the input end and the output end of the second non-inverting operational amplifier. The fourth resistor R4 is a dc coupling resistor, the fifth resistor R5 is a degeneration resistor, and the third capacitor C3 is a high frequency degeneration capacitor.
The strong light alarm circuit is used for driving the strong light source to emit light, the resistor R22 and the resistor R23 are arranged in parallel, the resistor R22 and the resistor R23 are both connected with a power supply end of the DSP data processing circuit, the other end of the resistor R22 is connected with a collector C of a switch tube Q5 through a concurrent light power supply, the other end of the resistor R23 is connected with a collector of the switch tube Q5 through a capacitor C25, a capacitor C26 and a light emitting power supply which are sequentially connected, the other ends of the capacitor C25 and the capacitor C26 are respectively grounded, an emitting stage of the switch tube Q5 is grounded, and a base stage of the switch tube Q5 is connected with the DSP data processing circuit through a resistor R24. The light-emitting power source is a 2046NM visible light LED light source, is strong and glaring, and can achieve a good warning effect. It is proposed to use 1-4 parallel arranged light emitting sources in the present circuit, the recommended number of which is 4.
The loud-sound alarm circuit is used for driving a loud-sound source to sound and comprises a loudspeaker, one end of the loudspeaker is connected with a resistor R2, the other end of the loudspeaker is connected with a collector of a switch tube Q2, an emitter of the switch tube is grounded, and a base level is connected with a DSP data processing circuit through a resistor R3. The sound source adopts 1KHz/120dB strong sound source, and the frequency of 1KHz is the most sensitive frequency of human ears. The human ear can feel strong uncomfortable ear-piercing feeling, can feel obvious oppression outside 20 meters, and the clear space can spread to outside 100 meters, reminds the field personnel to evacuate or handle.
The display and output circuit is used for visually displaying the atmospheric data and other information, and in the embodiment, the atmospheric data and other information are visually displayed through a 3.2-inch TFT-LCL display screen. And can be transmitted to other brother devices through an RS485 interface to share data.
The power supply circuit is used for supplying power to each circuit system, and the circuit converts a 24V power supply into a 5V power supply, a 3.3V power supply and a 1.2V power supply which are required by each circuit. For use by the respective circuits.
The DSP data processing circuit carries out corresponding processing on the signals sent by the signal processing and compensating circuit and sends the signals to the display and output circuit. In this circuit, U1 is a DSP data processing core chip. The gas sensor signal is DC coupled by the resistor R13 and the resistor R14 and sent to U1 for digital processing. A24 bit/10KHz AD circuit is integrated in the DSP chip, and the analog electric signal of the sensor is converted into a '0' and '1' digital signal which can be identified by the DSP. For digital processing. The resistor R11 and the resistor R12 are connected with an output display screen for performing visual display output. D1 is a system operation light, and the DSP chip will flash when performing data operation. "Y1" provides the circuit with an accurate computation clock. The capacitor C5 and the capacitor C6 are power supply bypass capacitors. U2 and the auxiliary circuits constitute the DSP power circuit. And supplying energy to the DSP arithmetic circuit. The capacitor C7 and the capacitor C8 are internal bypass capacitors. The PBO interface of the DSP data processing circuit is connected with the strong sound alarm circuit, and the PA/8LED _ ALM1 interface is connected with the strong light alarm circuit.
The invention also provides a gas detector with an audible and visual alarm function, and the gas detector is internally provided with the gas detection circuit disclosed in the specification.
The invention has the advantages of ingenious and stable circuit and simple structure. The concentration of various toxic and harmful gases in the atmosphere or the ratio of the toxic and harmful gases in the atmosphere can be detected at any time. And the circuit is provided with sound and strong light alarm reminding. When the concentration of the detected toxic and harmful gas reaches a set ratio, the device automatically reminds the personnel on site through the sharp high decibel and strong dazzling red light of ears, and the toxic and harmful gas exceeds the standard and is dangerous, so that the personnel need to withdraw or treat the gas immediately.
The invention has simple circuit structure, so that in practical application, the acousto-optic alarm part can be arranged in the machine, and the machine is convenient to carry and install. Can be widely applied to various occasions such as metallurgy, mining industry, traffic, communication, energy and chemical industry enterprises, aerospace, underground operation, tunnels, families and the like. Various highly harmful gases such as carbon monoxide, hydrogen sulfide, oxygen concentration, methane formaldehyde, ethylene, etc. can be monitored from time to time. And when the concentration exceeds a certain set limit, the danger is automatically informed to field personnel through sound and strong light.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principle of the present invention are intended to be included within the scope of the present invention.
Claims (5)
1. A gas detection circuit is characterized by comprising a gas sensor, a signal processing and compensating circuit, a DSP data processing circuit, a strong light alarm circuit, a strong sound alarm circuit, a display and output circuit and a public power supply circuit, wherein the gas sensor is used for converting toxic and harmful gases in the atmospheric environment into proportional electric signals, the signal processing and compensating circuit is used for amplifying weak electric signals output by the sensor to the amplitude of other circuits capable of being processed and processing, and performing corresponding circuit compensation to compensate distortion and loss of signals in the transmission process; the DSP data processing circuit carries out corresponding processing on the signals sent by the signal processing and compensating circuit and sends the processed signals to the display and output circuit; the strong light alarm circuit is used for driving the strong light source to emit light; the strong sound alarm circuit is used for driving a strong sound source to sound; the display and output circuit is used for visually displaying the atmospheric data and other information; the power supply circuit is used for supplying power to each circuit system; the strong light alarm circuit comprises a resistor R22 and a resistor R23 which are arranged in parallel, wherein the resistor R22 and the resistor R23 are both connected with a power supply end of the DSP data processing circuit, the other end of the resistor R22 is connected with a collector C of a switch tube Q5 through a concurrent light power supply, the other end of the resistor R23 is connected with a collector of a switch tube Q5 through a capacitor C25, a capacitor C26 and a light-emitting power supply which are sequentially connected, the other ends of the capacitor C25 and the capacitor C26 are respectively grounded, an emitter of the switch tube Q5 is grounded, and a base of the switch tube Q5 is connected with the DSP data processing circuit through a resistor R24.
2. The gas detection circuit of claim 1, wherein the loud alarm circuit comprises a speaker, one end of the speaker is connected with the resistor R2, the other end of the speaker is connected with the collector of the switch tube Q2, the emitter of the switch tube is grounded, and the base stage is connected with the DSP data processing circuit through the resistor R3.
3. The gas detection circuit of claim 1, wherein the light source is a high power LED visible high light source comprising 1-4 high light sources arranged in parallel.
4. The gas detection circuit of claim 2, wherein the speaker is a KHz/120dB intense acoustic source.
5. A gas detector having an audible and visual alarm function, characterized in that it comprises a gas detection circuit according to any one of claims 1 to 4.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011575437.XA CN113156054A (en) | 2020-12-28 | 2020-12-28 | Gas detection circuit and gas detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202011575437.XA CN113156054A (en) | 2020-12-28 | 2020-12-28 | Gas detection circuit and gas detector |
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| Publication Number | Publication Date |
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| CN113156054A true CN113156054A (en) | 2021-07-23 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202011575437.XA Pending CN113156054A (en) | 2020-12-28 | 2020-12-28 | Gas detection circuit and gas detector |
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| CN (1) | CN113156054A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112763667A (en) * | 2021-01-27 | 2021-05-07 | 深圳市安帕尔科技有限公司 | Realize gaseous modular circuit and gaseous detector that detects of multiple gas |
| CN117269391A (en) * | 2023-09-14 | 2023-12-22 | 中国航天员科研训练中心 | Gas detection circuit and gas signal acquisition method |
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| CN107301757A (en) * | 2017-06-07 | 2017-10-27 | 广西科技大学鹿山学院 | A kind of kitchen fuel gas alarm detector and its alarm detection procedure |
| CN209842840U (en) * | 2018-10-10 | 2019-12-24 | 北京燕山时代仪表有限公司 | Trace combustible volatile gas detection alarm |
| CN211857703U (en) * | 2020-02-22 | 2020-11-03 | 南宁职业技术学院 | Combustible gas alarm circuit |
| CN112102589A (en) * | 2020-08-17 | 2020-12-18 | 中煤科工集团重庆研究院有限公司 | Coal mine gas extraction intelligent pipe network leakage detection control system |
-
2020
- 2020-12-28 CN CN202011575437.XA patent/CN113156054A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2583670Y (en) * | 2002-12-04 | 2003-10-29 | 上海嘉安电器厂 | Alcohol detecting warning device |
| CN204514895U (en) * | 2015-03-30 | 2015-07-29 | 侯智德 | A kind of many gas detect instrument system |
| CN105651824A (en) * | 2015-12-19 | 2016-06-08 | 成都尼奥尔电子科技有限公司 | High-sensitivity natural gas detector based on alarm driving circuit |
| CN107301757A (en) * | 2017-06-07 | 2017-10-27 | 广西科技大学鹿山学院 | A kind of kitchen fuel gas alarm detector and its alarm detection procedure |
| CN209842840U (en) * | 2018-10-10 | 2019-12-24 | 北京燕山时代仪表有限公司 | Trace combustible volatile gas detection alarm |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112763667A (en) * | 2021-01-27 | 2021-05-07 | 深圳市安帕尔科技有限公司 | Realize gaseous modular circuit and gaseous detector that detects of multiple gas |
| CN117269391A (en) * | 2023-09-14 | 2023-12-22 | 中国航天员科研训练中心 | Gas detection circuit and gas signal acquisition method |
| CN117269391B (en) * | 2023-09-14 | 2025-01-07 | 中国航天员科研训练中心 | Gas detection circuit and gas signal acquisition method |
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