CN213812391U - Outdoor air quality monitoring station - Google Patents
Outdoor air quality monitoring station Download PDFInfo
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- CN213812391U CN213812391U CN202022850968.7U CN202022850968U CN213812391U CN 213812391 U CN213812391 U CN 213812391U CN 202022850968 U CN202022850968 U CN 202022850968U CN 213812391 U CN213812391 U CN 213812391U
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Abstract
The utility model relates to an outdoor air quality monitoring field, in particular to outdoor air quality monitoring station, include: the sensor module comprises one or more air quality sensors for monitoring air quality, a flow monitoring module for monitoring the gas flow passing through the air quality sensors and a temperature and humidity sensor for monitoring the temperature and humidity of the air quality sensors; and the temperature control module is connected with the temperature and humidity sensor and adjusts the working states of the heating resistance module and the fan according to the output of the temperature and humidity sensor. The utility model discloses with multiple sensor integration in a sensor module, constitute the application of modularization, can reduce the volume of outdoor air quality monitoring station by a wide margin.
Description
Technical Field
The utility model relates to an outdoor air quality monitoring field, in particular to outdoor air quality monitoring station.
Background
The existing national standard method for monitoring air quality four-gas two-dust mainly comprises a beta ray method, an oscillation balance method, a chemiluminescence method and other standard methods. These standard methods are expensive, bulky and have high requirements on ambient temperature and humidity. Belongs to the field of precision instruments. In applications, these devices are often installed in an air conditioned room or a container air conditioned room. This is not an optimal solution for ambient air quality monitoring networks that require more distribution.
Existing mini-stations and mini-stations target four gas two dust (CO, SO)2、NO2、O3And PM2.5 dust and PM10 dust), there are different monitoring methods. These methods are classified into electrochemical methods, metal semiconductor methods, optical particle counters, and the like. These methods have relatively sensitive characteristics with respect to ambient temperature, ambient humidity, ambient air pressure, and the like. The sensor itself is also affected by the flow, the zero drift, the full drift and so on, and the measurement error occurs.
In the similar technical application, the communication cost and the use of the cloud platform cannot meet various requirements. The data of the monitoring device is sent to the cloud platform through means such as 4G, and for the data volume of the level, the flow and the cost of 4G are slightly exceeded.
For the cloud platform, in the application of data, not only the transmission of the data but also a certain control and diagnosis capability for the air quality monitoring device itself should be provided.
The maintenance amount and the use cost of the prior art are still high, and the number of maintenance personnel is huge when the large-area distribution is carried out (hundreds of thousands of) in maintenance. For this level of application, the latter period directly leads to a straight-line increase in project cost.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to provide an indoor temperature and humidity is controllable low-cost, the outdoor air quality monitoring station of low maintenance cost based on modularization and extensible sensor module.
The utility model discloses an outdoor air quality monitoring station, include:
the sensor module comprises one or more air quality sensors for monitoring air quality, a flow monitoring module for monitoring the gas flow passing through the air quality sensors and a temperature and humidity sensor for monitoring the temperature and humidity of the air quality sensors;
and the temperature control module is connected with the temperature and humidity sensor and adjusts the working states of the heating resistance module and the fan according to the output of the temperature and humidity sensor.
Optionally, the air quality sensor includes at least one or more of a PM2.5 sensor, a PM10 sensor, a carbon monoxide sensor, a sulfur dioxide sensor, a nitrogen dioxide sensor, an ozone sensor, an ammonia sensor, and a hydrogen sulfide sensor.
Optionally, the wireless communication device further comprises a communication module, wherein the communication module comprises an NB-IoT module; the communication module receives data from the sensor module and transmits the data to a cloud platform.
Optionally, the flow monitoring module adjusts a pumping capacity of a pump according to a gas flow rate flowing through the air quality sensor to maintain the gas flow rate stable.
Optionally, the monitoring station further comprises a case, wherein the case is divided into an inner case, a top cover and a side cover; the upper part and the lower part of the two side walls of the inner box are respectively provided with an upper through hole and a lower through hole, and the top part is provided with a top through hole; the top cover covers the top through hole and the upper through hole, and a hot air channel is reserved between the top cover and the inner box; the side cover covers the lower through hole and leaves a cold air channel between the side cover and the inner box.
Optionally, the chassis includes a multilayer coating.
Optionally, the fan is disposed at an upper portion of the inner case, and guides the gas to flow out from the inside to the outside through the top through hole and the upper through hole.
Optionally, the lower through hole is an air inlet, and a filter screen and/or dustproof cotton are arranged at the air inlet.
Optionally, the heating resistance module starts to operate when the humidity exceeds a humidity threshold and the temperature is below a low temperature threshold.
Optionally, the fan is started when the temperature is above a high temperature threshold.
Compared with the prior art, the utility model, main difference and effect lie in:
the utility model discloses with multiple sensor integration in a sensor module, constitute the application of modularization, can reduce the volume of outdoor air quality monitoring station by a wide margin.
On the aspect of modular design, the defects that the existing equipment is troublesome to maintain and various consumables are replaced periodically are overcome. The sensor module is assembled into with multiple sensor, is equipped with flow monitoring module on the sensor module, can guarantee that airflow flow is stable, is equipped with temperature and humidity sensor and can compensate through software algorithm to the inside humiture of sensor module.
In the communication layer, an NB-IoT (Narrow Band Internet of Things) module with ultra-low cost is used, so that the existing communication means such as 4G are greatly reduced, and the wiring cost of field network wiring and the like is avoided. The narrow-band communication has strong and undisturbed signals, and the narrow-band communication can reduce the cost of an operator for the operator, and the integral cost is only about 5 yuan for 1 year.
In the aspect of the machine case, the arrangement of the top cover with the downward opening and the side cover avoids the phenomenon that pumping equipment is easy to enter water, the flow of diffusion equipment is unstable, the temperature and humidity compensation is difficult, and sunlight direct irradiation has great influence on the sensor. Meanwhile, the influence of temperature rise in the case caused by direct sunlight is weakened by the multiple layers of coatings of the case, and the outermost coating is a hydrophobic layer, so that the case can be effectively prevented from being watered.
In the aspect of temperature control, a plurality of temperature and humidity sensors are arranged in the case, and after the temperature average value of the temperature and humidity sensors changes, signals are output to the fan and the heating resistor module according to the changed temperature, so that the temperature and the humidity in the case can be controlled. The influence of the temperature and the humidity on the work of the sensor is reduced.
Drawings
Fig. 1 is a schematic diagram of a hardware connection of an outdoor air quality monitoring station according to an embodiment of the present invention;
fig. 2 is a schematic view of a housing and a gas circuit of an outdoor air quality monitoring station according to the present invention.
Detailed Description
In order to make the purpose and technical solution of the embodiments of the present invention clearer, the drawings of the embodiments of the present invention will be combined below to clearly and completely describe the technical solution of the embodiments of the present invention. It is to be understood that the embodiments described are some, but not all embodiments of the invention. Based on the described embodiments of the present invention, all other embodiments obtained by a person of ordinary skill in the art without creative efforts belong to the protection scope of the present invention.
The design idea of the utility model is that: the existing shell technology and communication technology which are suitable for the field of environment monitoring are combined with the technologies such as temperature and humidity control, flow control and sensor correction compensation in an all-around manner, the information advantage of a cloud platform is assisted, and a large-scale monitoring network in the era of the Internet of things is created.
The utility model discloses an embodiment relates to an outdoor air quality monitoring station. Fig. 1 is a hardware connection schematic diagram of an outdoor air quality monitoring station according to an embodiment of the present invention.
Specifically, as shown in fig. 1, the outdoor air quality monitoring station includes a sensor module 1, a temperature control module 2, a heating resistance module 3, a fan 5 and a communication module (not shown) installed in a chassis.
The sensor module 1 comprises at least one air quality sensor, which may be one or more of a PM2.5 sensor, a PM10 sensor, a carbon monoxide sensor, a sulphur dioxide sensor, a nitrogen dioxide sensor, an ozone sensor, an ammonia sensor and a hydrogen sulphide sensor. In a preferred embodiment, the sensor module 1 comprises 6 different types of air quality sensors for monitoring four-gas-two-dust in air.
The various sensors are integrated in a module, and further through the plug-and-play structural design, the space occupied by the sensors can be greatly reduced, and then the volume of the outdoor air quality monitoring equipment can be greatly reduced.
The sensor module 1 further comprises a flow monitoring module 11, and the flow monitoring module 11 is used for monitoring the gas flow passing through the air quality sensor. Since the output data of the sensor is more reliable if the sensor operates in a stable gas flow environment, maintaining the stability of the gas flow helps to improve the quality of the outdoor air quality monitoring station. When the flow monitoring module 11 detects that the gas flow does not meet the requirement, the voltage of the pump 12 is adjusted, and the opening and closing amplitude of the electromagnetic valve is changed, so that the gas flow is always kept at a preset value.
The sensor module 1 is added with a flow monitoring function, so that the problem of insufficient driving force caused by aging of the pump 12 can be compensated. As the pump 12 ages, the input voltage of the pump is controlled to maintain a steady flow of gas slowly flowing through the air quality sensor, so as to improve the accuracy and consistency of sensing, and enhance the anti-interference capability of the sensor.
Further, the pump 12 is arranged in the sensor module 1 as a post pump, so that the gas flowing through the air quality sensor has no pressure, and the influence of the pressure on the sensor is eliminated.
The sensor module 1 further includes a temperature and humidity sensor 13. On the one hand, the data output by the temperature and humidity sensor 13 are transmitted to a control unit (not shown), and the control unit can perform software-level compensation on the data output by the sensor module 1 by using a software algorithm; on the other hand, the data output by the temperature and humidity sensor 13 can also be transmitted to the temperature control module 2, the temperature control module 2 judges according to the data, and if the temperature and humidity do not accord with the preset threshold value, the heating resistance module 3 and/or the fan 5 are/is started to carry out cooling and dehumidifying work.
Preferably, two sets of temperature and humidity sensors are arranged in the temperature control module 2, and when the average temperature value of the two sets of temperature and humidity sensors changes, signals are output to the fan 5 and the heating resistor module 3 according to the change, so that the defect that the environment in the case cannot be integrally reflected by data acquired by a single sensor is overcome.
Specifically, a humidity threshold, a low temperature threshold, and a high temperature threshold are set in advance. And when the temperature detected by the temperature and humidity sensor 13 is higher than the high-temperature threshold, starting the fan 5 to discharge the high-temperature gas in the case to the outside of the case. At the same time, moisture in the cabinet can also be carried out. When the temperature detected by the temperature and humidity sensor 13 is lower than the low-temperature threshold and/or the humidity is higher than the humidity threshold, the heating resistor module 3 is started, and high-temperature gas and moisture are simultaneously urged to be discharged outside the case.
The utility model discloses with one or more sensor integration and form plug and play's sensor module 12, can reduce the fortune dimension cost by a wide margin. The calibration work can be brought back to the laboratory for batch calibration, rather than calibration on site one by one. This has positive effects on the consistency of the sensor and the problems of artificial accidental damage and the like. The maintainer only needs to go to the monitoring website regularly, changes the sensor module, then take back the sensor module that needs the demarcation can. And a certain standard monitoring station can be selected in a laboratory, and calibration can be completed only by placing the modules in a large-scale closed space near the standard station in batches and comparing numerical values.
The utility model discloses because the design of internal sensor modularization saves more spaces, can increase more sensor parameters on original basisAnd has the expandable characteristic. The utility model can collect the conventional 4 gas 2 dust (PM2.5, PM10, CO, SO)2、NO2、O3) In addition to parameters, NH may also be collected3、H2S and other parameters, the cost performance can be improved.
In some embodiments, the communication module comprises an NB-IoT module. The communication module receives data from the sensor module 1 and transmits the data to the cloud platform.
The utility model discloses use communication methods such as NB-IoT module, can reduce 4G card and wiring cost originally, can reduce outdoor air quality monitoring's communication expense by a wide margin.
As shown in fig. 2, in some embodiments, the enclosure of the outdoor air quality monitoring station includes an inner box 200, a top cover 201, and side covers 202.
Upper and lower portions of both side walls of the inner box 200 are provided with upper and lower through holes (not shown), respectively, and a top through hole (not shown) is provided at the top of the inner box 200. The upper through hole, the lower through hole and the top through hole are arranged to enable air inside and outside the case to be circulated, and specifically, the upper through hole, the lower through hole and the top through hole can be a single large through hole or a group of small through holes. In a preferred embodiment, the lower through hole as the air inlet is provided with a filter screen and/or dustproof cotton.
The air outside the case is slowly sent into the case through the air inlet, and the front end filtration is realized to filter screen and/or dustproof cotton that air inlet department set up, can filter great dust, prevents that big dust from destroying circuit board etc. stabilizes air quality sensor, promotes the sensor precision. In addition, the consumable of equipment can refer to the sensor and change the life-span and design, accomplishes to change the filter when changing the sensor every year, reduces later maintenance cost and use cost.
The top cover 201 and the side cover 202 are designed to be opened downwards, so that the possibility of foreign matters and rainwater entering the interior of the case is reduced. The top cover 201 is covered on the top of the inner box 200 like a hat, and the top through hole and the upper through hole are wrapped inside, so that the probability that foreign matters and rainwater enter the inner part of the case is further reduced. A gap is formed between the top cover 201 and the inner case 200 to form a hot gas path 203 for discharging the gas flowing out of the cabinet along a predetermined path. The side cover 202 covers the lower through hole and leaves a cold air passage 204 with the inner case. The air sucked into the cabinet enters through the cold air passage 204.
The chassis structure shown in fig. 2 adopts a unique air inlet mode, and avoids the defects that pump suction type equipment is easy to feed water, diffusion type equipment is unstable in flow rate, and temperature and humidity compensation is difficult. The presence of the hot air path 203 and the cold air path 204 also objectively reduces the problem of temperature rise in the cabinet caused by direct sunlight.
Preferably, the fan 5 is disposed at an upper portion of the inner case 200, i.e., at a position near the top through hole and the upper through hole, and guides the gas in the case to flow out from the inside to the outside through the top through hole and the upper through hole.
The fan 5, the cold air channel 204 and the hot air channel 203 form a heat dissipation air channel, and the purpose of high-efficiency heat dissipation is achieved through physical circulation. In the first stage, cool outside air enters the inside of the cabinet through the cool air duct 204 while hot air inside the cabinet is forced out through the hot air duct 203. In the second stage, when the sunshine is strong, the fan 5 in the inner box 200 supplies air upwards to take away the sunshine heat absorbed by the top of the case and form pressure on the upper air in the inner box 200. And in the third stage, the upper gas is sprayed out from the upper through hole, and is crossly mixed with the external cold air to cool the outer wall of the inner box 200 for the third time.
In some embodiments, the chassis may be a waterproof and dustproof class IP55 chassis with multiple layers of coating and water sinks disposed on the exterior of the chassis. Preferably, the multilayer coating comprises: the anti-rust coating comprises a metal matrix layer, an anti-oxidation and anti-rust coating, an acid-base corrosion resistant layer, a color layer, an anti-UV (ultraviolet) layer and an anti-static layer. The outermost antistatic layer plays a role in dewatering, can effectively guide water drops to flow out of the water tank and cannot be immersed into the case.
In the above embodiment, after the gas is brought into the case by the atmospheric pressure, the sensor module 1 collects the sample gas at a certain flow rate. The overall design combines two reliable sampling modes in the field of gas monitoring: diffusion and pump suction, and simultaneously, the temperature control module 2 and the temperature and humidity compensation algorithm of the sensor are used for removing various factors of the interference sensor on each layer.
On the mathematical model can be considered as: (original value) ((temperature, humidity, air pressure flow) + zero drift) ((original value)) full point drift amount is the final output. In the whole model, when the variable is the temperature, humidity and air pressure flow, the value of the final output is greatly influenced. We have measured ppb levels of sample gas in the field of environmental monitoring. These disturbances will have a large impact on the results.
In the drawings, some features of the structures or methods may be shown in a particular arrangement and/or order. However, it is to be understood that such specific arrangement and/or ordering may not be required. Rather, in some embodiments, the features may be arranged in a manner and/or order different from that shown in the illustrative figures. Additionally, the inclusion of a structural or methodical feature in a particular figure is not meant to imply that such feature is required in all embodiments, and in some embodiments, may not be included or may be modified or may be combined with other features.
The method embodiments of the present invention can be implemented in software, hardware, firmware, and the like. Whether implemented in software, hardware, or firmware, the instruction code may be stored in any type of computer-accessible memory (e.g., permanent or modifiable, volatile or non-volatile, solid or non-solid, fixed or removable media, etc.). Also, the Memory may be, for example, Programmable Array Logic (PAL), Random Access Memory (RAM), Programmable Read Only Memory (PROM), Read-Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), a magnetic disk, an optical disk, a Digital Versatile Disk (DVD), or the like.
It should be noted that, each unit/module mentioned in each device implementation of the present invention is a logic unit/module, and physically, a logic unit may be a physical unit, or may be a part of a physical unit, and may also be implemented by a combination of a plurality of physical units, and the physical implementation manner of these logic units itself is not the most important, and the combination of the functions implemented by these logic units is the key to solve the technical problem provided by the present invention. Furthermore, in order to highlight the innovative part of the present invention, the above-mentioned embodiments of the device of the present invention do not introduce the elements that are not closely related to the solution of the technical problem proposed by the present invention, which does not indicate that the above-mentioned embodiments of the device do not have other elements.
It is to be noted that in the claims and the description of the present patent, relational terms such as first and second, and the like are used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, the use of the verb "comprise a" to define an element does not exclude the presence of another, same element in a process, method, article, or apparatus that comprises the element.
While the invention has been shown and described with reference to certain preferred embodiments thereof, it will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the invention.
Claims (10)
1. An outdoor air quality monitoring station, comprising:
the sensor module comprises one or more air quality sensors for monitoring air quality, a flow monitoring module for monitoring the gas flow passing through the air quality sensors and a temperature and humidity sensor for monitoring the temperature and humidity of the air quality sensors;
and the temperature control module is connected with the temperature and humidity sensor and adjusts the working states of the heating resistance module and the fan according to the output of the temperature and humidity sensor.
2. The monitoring station of claim 1, wherein the air quality sensor includes at least one or more of a PM2.5 sensor, a PM10 sensor, a carbon monoxide sensor, a sulfur dioxide sensor, a nitrogen dioxide sensor, an ozone sensor, an ammonia sensor, and a hydrogen sulfide sensor.
3. The monitoring station of claim 1, further comprising a communication module, the communication module comprising an NB-IoT module; the communication module receives data from the sensor module and transmits the data to a cloud platform.
4. The monitoring station of claim 1, wherein the flow monitoring module adjusts a pumping capacity of a pump based on a flow of gas through the air quality sensor to maintain the flow of gas steady.
5. The monitoring station of claim 1, further comprising a case divided into an inner case, a top cover, and side covers;
the upper part and the lower part of the two side walls of the inner box are respectively provided with an upper through hole and a lower through hole, and the top part is provided with a top through hole;
the top cover covers the top through hole and the upper through hole, and a hot air channel is reserved between the top cover and the inner box;
the side cover covers the lower through hole and leaves a cold air channel between the side cover and the inner box.
6. The monitoring station of claim 5, wherein the chassis comprises a multilayer coating.
7. The monitoring station of claim 5, wherein the fan is disposed at an upper portion of the inner box to direct gas flow from inside to outside via the top through hole and the upper through hole.
8. The monitoring station of claim 5, wherein the lower through hole is an air inlet, and a filter screen and/or dust cotton is disposed at the air inlet.
9. The monitoring station of claim 1, wherein the heating resistance module begins operation when the humidity exceeds a humidity threshold and the temperature is below a low temperature threshold.
10. The monitoring station of claim 1, wherein the fan begins operating when the temperature is above a high temperature threshold.
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| Application Number | Priority Date | Filing Date | Title |
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| CN202022850968.7U CN213812391U (en) | 2020-12-02 | 2020-12-02 | Outdoor air quality monitoring station |
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| CN202022850968.7U CN213812391U (en) | 2020-12-02 | 2020-12-02 | Outdoor air quality monitoring station |
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| CN213812391U true CN213812391U (en) | 2021-07-27 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114674987A (en) * | 2022-04-12 | 2022-06-28 | 珠海格力电器股份有限公司 | Formaldehyde detection method and device based on formaldehyde sensor and air purifier |
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2020
- 2020-12-02 CN CN202022850968.7U patent/CN213812391U/en active Active
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN114674987A (en) * | 2022-04-12 | 2022-06-28 | 珠海格力电器股份有限公司 | Formaldehyde detection method and device based on formaldehyde sensor and air purifier |
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