CN211317390U - Indoor environment detection system - Google Patents
Indoor environment detection system Download PDFInfo
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- CN211317390U CN211317390U CN201921999331.5U CN201921999331U CN211317390U CN 211317390 U CN211317390 U CN 211317390U CN 201921999331 U CN201921999331 U CN 201921999331U CN 211317390 U CN211317390 U CN 211317390U
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- 238000001514 detection method Methods 0.000 title claims abstract description 24
- WSFSSNUMVMOOMR-UHFFFAOYSA-N Formaldehyde Chemical compound O=C WSFSSNUMVMOOMR-UHFFFAOYSA-N 0.000 claims abstract description 33
- RAHZWNYVWXNFOC-UHFFFAOYSA-N Sulphur dioxide Chemical compound O=S=O RAHZWNYVWXNFOC-UHFFFAOYSA-N 0.000 claims abstract description 24
- CURLTUGMZLYLDI-UHFFFAOYSA-N Carbon dioxide Chemical compound O=C=O CURLTUGMZLYLDI-UHFFFAOYSA-N 0.000 claims abstract description 22
- 239000003990 capacitor Substances 0.000 claims abstract description 21
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 claims abstract description 12
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 claims abstract description 12
- UGFAIRIUMAVXCW-UHFFFAOYSA-N Carbon monoxide Chemical compound [O+]#[C-] UGFAIRIUMAVXCW-UHFFFAOYSA-N 0.000 claims abstract description 11
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 claims abstract description 11
- 239000001569 carbon dioxide Substances 0.000 claims abstract description 11
- 229910002092 carbon dioxide Inorganic materials 0.000 claims abstract description 11
- 229910002091 carbon monoxide Inorganic materials 0.000 claims abstract description 11
- 239000004302 potassium sorbate Substances 0.000 claims description 3
- 230000007613 environmental effect Effects 0.000 abstract description 3
- 230000009286 beneficial effect Effects 0.000 abstract description 2
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 abstract 2
- 229910052757 nitrogen Inorganic materials 0.000 abstract 1
- 238000010586 diagram Methods 0.000 description 4
- 230000006870 function Effects 0.000 description 4
- 210000000056 organ Anatomy 0.000 description 4
- 238000012360 testing method Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 2
- 230000008859 change Effects 0.000 description 1
- 230000003247 decreasing effect Effects 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000003344 environmental pollutant Substances 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000036541 health Effects 0.000 description 1
- 238000007726 management method Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 230000008569 process Effects 0.000 description 1
- 239000012855 volatile organic compound Substances 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
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Abstract
The utility model relates to the field of environmental detection, and discloses an indoor environment detection system, which comprises a singlechip, a temperature sensor, a humidity sensor, an air flow rate detector, fresh air volume detection equipment, a sulfur dioxide sensor, a carbon dioxide sensor, a nitrogen dioxide sensor, a carbon monoxide sensor, an ozone sensor, a formaldehyde sensor, a TVOC sensor, a PM2.5 sensor and a power supply module, wherein the temperature sensor, the humidity sensor, the air flow rate detector, the fresh air volume detection equipment, the sulfur dioxide sensor, the carbon dioxide sensor, the nitrogen; the power supply module comprises a first triode, a first resistor, a second resistor, a power supply, a first capacitor, a third potentiometer, a fourth resistor, a second triode, a voltage comparator, a first voltage-regulator tube, a third triode, a fifth resistor, a second diode, a fourth triode, a buzzer and a second capacitor, wherein the base of the first triode is connected with the anode of the first voltage-regulator tube. Implement the utility model discloses an indoor environment detecting system has following beneficial effect: the safety and the reliability of the circuit are higher.
Description
Technical Field
The utility model relates to an environment measuring field, in particular to indoor environment detecting system.
Background
The indoor environment detection is to quantitatively measure the concentration change of environmental factors and other indoor environmental pollutants harmful to human health in an intermittent or continuous mode by using a modern scientific and technical method, and observe and analyze the scientific activities of the environmental influence process and degree. The purpose of indoor environment detection is to timely, accurately and comprehensively reflect the current situation and development trend of indoor environment quality and provide scientific basis for indoor environment management, pollution source control, indoor environment planning and indoor environment evaluation. Some power supply parts of the indoor environment detection system in the conventional technology lack corresponding circuit protection functions, such as: the safety and reliability of the circuit are low due to the lack of the current-limiting protection function.
SUMMERY OF THE UTILITY MODEL
The to-be-solved technical problem of the utility model lies in, to the above-mentioned defect of prior art, provide the higher indoor environment detecting system of security and reliability of a circuit.
The utility model provides a technical scheme that its technical problem adopted is: the indoor environment detection system comprises a single chip microcomputer, a temperature sensor, a humidity sensor, an air flow rate detector, fresh air volume detection equipment, a sulfur dioxide sensor, a carbon dioxide sensor, a nitrogen dioxide sensor, a carbon monoxide sensor, an ozone sensor, a formaldehyde sensor, a TVOC sensor, a PM2.5 sensor and a power supply module, wherein the temperature sensor, the humidity sensor, the air flow rate detector, the fresh air volume detection equipment, the sulfur dioxide sensor, the carbon dioxide sensor, the nitrogen dioxide sensor, the carbon monoxide sensor, the ozone sensor, the formaldehyde sensor, the TVOC sensor, the PM2.5 sensor and the power supply module are all connected with the single chip microcomputer;
the power supply module comprises a first triode, a first resistor, a second resistor, a power supply, a first capacitor, a third potentiometer, a fourth resistor, a second triode, a voltage comparator, a first voltage regulator tube, a third triode, a fifth resistor, a second diode, a fourth triode, a buzzer and a second capacitor, wherein the base electrode of the first triode is connected with the anode of the first voltage regulator tube, the collector electrode of the first triode is connected with one end of the first resistor, the other end of the first resistor is respectively connected with one end of the first capacitor, one end of the second resistor and the inverting input end of the voltage comparator, the other end of the second resistor is respectively connected with the power supply, one fixed end of the third potentiometer, the emitter electrode of the third triode, one end of the fifth resistor, the anode of the second diode and one end of the second capacitor, the non-inverting input end of the voltage comparator is connected with the sliding end of the third potentiometer, the other fixed end of the third potentiometer is respectively connected with one end of the fourth resistor and the emitting electrode of the second triode, the base electrode of the second triode is respectively connected with the output end of the voltage comparator and the base electrode of the third triode, the collector electrode of the third triode is respectively connected with the cathode of the first voltage-regulator tube and the single chip microcomputer, the base electrode of the fourth triode is connected with the other end of the fifth resistor, the emitting electrode of the fourth triode is connected with the cathode of the second diode, the collector electrode of the fourth triode is connected with one end of the buzzer, the emitting electrode of the first triode is respectively connected with the other end of the first capacitor, the other end of the fourth resistor, the collector electrode of the second triode, the other end of the buzzer and the other end of the second capacitor, the model of the second diode is S-152T.
Indoor environment detecting system in, power module still includes sixth resistance, the one end of sixth resistance with the other end of second resistance is connected, the other end of sixth resistance with the projecting pole of third triode is connected, the resistance of sixth resistance is 43k omega.
In the indoor environment detecting system, the power supply module further includes a third diode, an anode of the third diode is connected to an output end of the voltage comparator, a cathode of the third diode is connected to a base of the third triode, and a model of the third diode is E-202.
In the indoor environment detecting system of the present invention, the first triode is an NPN-type triode.
Indoor environment detecting system in, the second triode is PNP type triode.
Indoor environment detecting system in, the third triode is PNP type triode.
Indoor environment detecting system in, the fourth triode is PNP type triode.
Implement the utility model discloses an indoor environment detecting system has following beneficial effect: because be equipped with the singlechip, a weighing sensor and a temperature sensor, humidity transducer, air flow rate detector, fresh air volume check out test set, the sulfur dioxide sensor, the carbon dioxide sensor, the nitrogen dioxide sensor, the carbon monoxide sensor, the ozone sensor, the formaldehyde sensor, the TVOC sensor, PM2.5 sensor and power module, power module includes first triode, first resistance, the second resistance, power supply, first electric capacity, the third potentiometre, the fourth resistance, the second triode, voltage comparator, first stabilivolt, the third triode, the fifth resistance, the second diode, the fourth triode, bee calling organ and second electric capacity, the second diode is used for carrying out current-limiting protection, therefore the security and the reliability of circuit are higher.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to these drawings without creative efforts.
Fig. 1 is a schematic structural diagram of an embodiment of an indoor environment detection system of the present invention;
fig. 2 is a schematic circuit diagram of the power supply module in the embodiment.
Detailed Description
The technical solutions in the embodiments of the present invention will be described clearly and completely with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
In the embodiment of the indoor environment detecting system of the present invention, the schematic structural diagram of the indoor environment detecting system is shown in fig. 1. In fig. 1, this indoor environment detection system includes singlechip 1, temperature sensor 2, humidity transducer 3, air flow rate detector 4, fresh air volume check out test set 5, sulfur dioxide sensor 6, carbon dioxide sensor 7, nitrogen dioxide sensor 8, carbon monoxide sensor 9, ozone sensor 10, formaldehyde sensor 11, TVOC sensor 12, PM2.5 sensor 13 and power module 14, wherein, temperature sensor 2, humidity transducer 3, air flow rate detector 4, fresh air volume check out test set 5, sulfur dioxide sensor 6, carbon dioxide sensor 7, nitrogen dioxide sensor 8, carbon monoxide sensor 9, ozone sensor 10, formaldehyde sensor 11, TVOC sensor 12, PM2.5 sensor 13 and power module 14 all are connected with singlechip 1.
The temperature sensor 2 is used for detecting the indoor air temperature; the humidity sensor 3 is used for detecting the indoor air humidity; the air flow rate detector 4 is used for detecting the indoor air flow rate; the fresh air volume detection device 5 is used for detecting the fresh air volume flowing into the room; the sulfur dioxide sensor 6 is used for detecting the concentration of sulfur dioxide in indoor air; the nitrogen dioxide sensor 8 is used for detecting the concentration of carbon dioxide in indoor air; the nitrogen dioxide sensor 8 is used for detecting the concentration of nitrogen dioxide in indoor air; the carbon monoxide sensor 9 is used for detecting the concentration of carbon monoxide in indoor air; the ozone sensor 10 is used for detecting the concentration of ozone in indoor air; the formaldehyde sensor 11 is used for detecting the concentration of formaldehyde in indoor air; the TVOC sensor 12 is configured to detect a concentration of total volatile organic compounds in the indoor air; the PM2.5 sensor 13 is used to detect the concentration of PM2.5 in the indoor air.
Temperature sensor 2, humidity transducer 3, air flow rate detector 4, fresh air volume check out test set 5, sulfur dioxide sensor 6, carbon dioxide sensor 7, nitrogen dioxide sensor 8, carbon monoxide sensor 9, ozone sensor 10, formaldehyde sensor 11, TVOC sensor 12, PM2.5 sensor 13 transmits the data information who records for singlechip 1, handle the back through singlechip 1 and save in the memory, play out through the display screen simultaneously, when having any data superscript in the detected data, singlechip 1 control alarm reports to the police.
Fig. 2 is a schematic circuit diagram of the power supply module in this embodiment, in fig. 2, the power supply module 14 includes a first transistor Q1, a first resistor R1, a second resistor R2, a power supply VCC, a first capacitor C1, a third potentiometer RP3, a fourth resistor R4, a second transistor Q2, a voltage comparator a1, a first voltage regulator D1, a third transistor Q3, a fifth resistor R5, a second diode D2, a fourth transistor Q4, a buzzer B, and a second capacitor C2, a base of the first transistor Q1 is connected to an anode of the first voltage regulator D1, a collector of the first transistor Q9 is connected to one end of the first resistor R1, another end of the first resistor R1 is connected to one end of the first capacitor C1, one end of the second resistor R1, and an input end of the voltage comparator a1, another end of the second resistor R2 is connected to the VCC, and an emitter terminal of the third resistor R3, and an emitter 3 of the third resistor R3, One end of a fifth resistor R5, the anode of a second diode D2 and one end of a second capacitor C2 are connected, the non-inverting input end of a voltage comparator A1 is connected with the sliding end of a third potentiometer RP3, the other fixed end of the third potentiometer RP3 is respectively connected with one end of a fourth resistor R4 and the emitter of a second triode Q2, the base of the second triode Q2 is respectively connected with the output end of a voltage comparator A1 and the base of a third triode Q3, the collector of the third triode Q3 is respectively connected with the cathode of a first voltage regulator D1 and the single chip microcomputer 1, the base of a fourth triode Q4 is connected with the other end of the fifth resistor R5, the emitter of the fourth triode Q4 is connected with the cathode of a second diode D2, the collector of the fourth triode Q4 is connected with one end of a buzzer B, the emitter of the first triode Q1 is respectively connected with the other end of a first capacitor C1 and the other end of a fourth resistor R4, The collector of the second triode Q2, the other end of the buzzer B and the other end of the second capacitor C2 are connected.
In this embodiment, the second diode D2 is a current limiting diode, and is used for current limiting protection of the emitter current of the fourth transistor Q4. The current limiting protection principle is as follows: when the emitter current of the fourth triode Q4 is large, the second diode D2 can reduce the emitter current of the fourth triode Q4 to keep the fourth triode Q4 in a normal working state, so that the elements in the circuit are not burnt out due to too large current, and the safety and reliability of the circuit are high. It should be noted that in the present embodiment, the second diode D2 has a model number S-152T. Of course, in practical applications, the second diode D2 may also be another type of diode with similar functions.
The power supply VCC is pulsating direct current obtained by rectifying and reducing voltage of commercial power. The voltage comparator a1 is model OP 07.
The operating principle of the power supply module 14 is as follows: the core element of the circuit is a voltage comparator A1, the voltage at the non-inverting input end of the circuit is obtained by dividing the voltage through a third potentiometer RP3 and a fourth resistor R4, the voltage at the inverting input end of the circuit is obtained by dividing the voltage through a second resistor R2, a first capacitor C1 and other elements, and under the condition of normal voltage, the voltage at the inverting input end of the voltage comparator A1 is higher than the voltage at the non-inverting input end, so the output end of the voltage comparator A is at a low level, at the moment, the second triode Q2 and the third triode Q3 are both turned on, the second triode Q2 is turned off, the single chip microcomputer 1 normally works, when the overvoltage of the power supply exceeds a critical value, the first voltage regulator D1 is broken down, the base of the first triode Q1 is electrified, so that the voltage at the inverting input end of the voltage comparator A1 is lower than the voltage at the non-inverting input end, the voltage comparator A1 outputs a high level, the third triode Q3 is turned off, and at the same time, therefore, when the voltage is slightly lower than the over-voltage threshold, the voltage at the non-inverting input terminal of the voltage comparator a1 is still higher than the voltage at the inverting input terminal, and the circuit will not operate, preventing jitter around its threshold.
Fifth resistance R5, fourth triode Q4, second electric capacity C2 and bee calling organ B constitute power failure warning circuit, when power supply VCC's voltage is normal, because fourth triode Q4's conducting characteristic, fourth triode Q4 does not switch on this moment, when bee calling organ B does not make a sound, when meetting power supply VCC disconnection, second electric capacity C2 discharges to fourth triode Q4's projecting pole through second diode D2, fourth triode Q4 switches on, bee calling organ B sends the chimes of doom, the warning has been reminded to have a power failure.
In this embodiment, the first transistor Q1 is an NPN transistor, the second transistor Q2 is a PNP transistor, the third transistor Q3 is a PNP transistor, and the fourth transistor Q4 is a PNP transistor. Certainly, in practical applications, the first transistor Q1 may also be a PNP transistor, and the second transistor Q2, the third transistor Q3, and the fourth transistor Q4 may also be NPN transistors, but the structure of the circuit at this time also changes accordingly.
In this embodiment, the power supply module 14 further includes a sixth resistor R6, one end of the sixth resistor R6 is connected to the other end of the second resistor R2, and the other end of the sixth resistor R6 is connected to an emitter of the third transistor Q3. The sixth resistor R6 is a current limiting resistor for current limiting protection. The current limiting protection principle is as follows: when the current of the branch where the sixth resistor R6 is located is large, the magnitude of the current of the branch where the sixth resistor R6 is located can be reduced by the sixth resistor R6, so that the branch can be kept in a normal operating state, and the components in the circuit cannot be burned out due to the large current, so that the safety and reliability of the circuit are further enhanced. It should be noted that, in the present embodiment, the resistance of the sixth resistor R6 is 43k Ω. Of course, in practical applications, the resistance of the sixth resistor R6 may be adjusted according to specific situations, that is, the resistance of the sixth resistor R6 may be increased or decreased according to specific situations.
In this embodiment, the power supply module 14 further includes a third diode D3, an anode of the third diode D3 is connected to the output terminal of the voltage comparator a1, and a cathode of the third diode D3 is connected to the base of the third transistor Q3. The third diode D3 is a current limiting diode, and is used for current limiting protection of the base current of the third transistor Q3. The current limiting protection principle is as follows: when the base current of the third transistor Q3 is large, the base current of the third transistor Q3 can be reduced by the third diode D3 to keep it in a normal working state, and thus, the device in the circuit is not burned out due to too large current, so as to further enhance the safety and reliability of the circuit. It should be noted that in the present embodiment, the third diode D3 has a model number E-202. Of course, in practical applications, the third diode D3 may be another type of diode with similar functions.
In short, in the present embodiment, since the current-limiting diode is provided in the power supply module 14, the safety and reliability of the circuit are high.
The above description is only a preferred embodiment of the present invention, and should not be taken as limiting the invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims (7)
1. An indoor environment detection system is characterized by comprising a single chip microcomputer, a temperature sensor, a humidity sensor, an air flow rate detector, fresh air volume detection equipment, a sulfur dioxide sensor, a carbon dioxide sensor, a nitrogen dioxide sensor, a carbon monoxide sensor, an ozone sensor, a formaldehyde sensor, a TVOC sensor, a PM2.5 sensor and a power supply module, wherein the temperature sensor, the humidity sensor, the air flow rate detector, the fresh air volume detection equipment, the sulfur dioxide sensor, the carbon dioxide sensor, the nitrogen dioxide sensor, the carbon monoxide sensor, the ozone sensor, the formaldehyde sensor, the TVOC sensor, the PM2.5 sensor and the power supply module are all connected with the single chip microcomputer;
the power supply module comprises a first triode, a first resistor, a second resistor, a power supply, a first capacitor, a third potentiometer, a fourth resistor, a second triode, a voltage comparator, a first voltage regulator tube, a third triode, a fifth resistor, a second diode, a fourth triode, a buzzer and a second capacitor, wherein the base electrode of the first triode is connected with the anode of the first voltage regulator tube, the collector electrode of the first triode is connected with one end of the first resistor, the other end of the first resistor is respectively connected with one end of the first capacitor, one end of the second resistor and the inverting input end of the voltage comparator, the other end of the second resistor is respectively connected with the power supply, one fixed end of the third potentiometer, the emitter electrode of the third triode, one end of the fifth resistor, the anode of the second diode and one end of the second capacitor, the non-inverting input end of the voltage comparator is connected with the sliding end of the third potentiometer, the other fixed end of the third potentiometer is respectively connected with one end of the fourth resistor and the emitting electrode of the second triode, the base electrode of the second triode is respectively connected with the output end of the voltage comparator and the base electrode of the third triode, the collector electrode of the third triode is respectively connected with the cathode of the first voltage-regulator tube and the single chip microcomputer, the base electrode of the fourth triode is connected with the other end of the fifth resistor, the emitting electrode of the fourth triode is connected with the cathode of the second diode, the collector electrode of the fourth triode is connected with one end of the buzzer, the emitting electrode of the first triode is respectively connected with the other end of the first capacitor, the other end of the fourth resistor, the collector electrode of the second triode, the other end of the buzzer and the other end of the second capacitor, the model of the second diode is S-152T.
2. The indoor environment detection system according to claim 1, wherein the power supply module further includes a sixth resistor, one end of the sixth resistor is connected to the other end of the second resistor, the other end of the sixth resistor is connected to an emitter of the third transistor, and a resistance of the sixth resistor is 43k Ω.
3. The indoor environment detection system of claim 2, wherein the power supply module further comprises a third diode, an anode of the third diode is connected to the output terminal of the voltage comparator, a cathode of the third diode is connected to the base of the third transistor, and the third diode is of type E-202.
4. The indoor environment detection system according to any one of claims 1 to 3, wherein the first transistor is an NPN transistor.
5. The indoor environment detection system according to any one of claims 1 to 3, wherein the second transistor is a PNP transistor.
6. The indoor environment detection system according to any one of claims 1 to 3, wherein the third transistor is a PNP type transistor.
7. The indoor environment detection system according to any one of claims 1 to 3, wherein the fourth transistor is a PNP type transistor.
Priority Applications (1)
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CN201921999331.5U CN211317390U (en) | 2019-11-18 | 2019-11-18 | Indoor environment detection system |
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CN201921999331.5U CN211317390U (en) | 2019-11-18 | 2019-11-18 | Indoor environment detection system |
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CN211317390U true CN211317390U (en) | 2020-08-21 |
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CN201921999331.5U Expired - Fee Related CN211317390U (en) | 2019-11-18 | 2019-11-18 | Indoor environment detection system |
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Granted publication date: 20200821 |