Sensor for monitoring environment air grain concentration

Abstract

A transducer used for monitoring particle concentration of environmental air is prepared as crossing light channel of light source emitter with air stream channel at detection hole of air stream channel, entering light refracted from detection hole into light detector through detection channel, setting air inlet at one side of detection hole on air stream channel and setting air extraction fan at another side of said detection hole.

Description

Technical field [0001] The invention relates to a sensor for monitoring the concentration of ambient air particles. Background technique [0002] There are two commonly used sensor methods for existing atmospheric particulate matter concentration monitoring instruments: β-ray absorption method and optical scattering method. Among them, the β-ray absorption method is widely used because it is not affected by the type, color, shape and other factors of the particles. However, the β-ray absorption method requires the use of a filter membrane as a carrier to intercept the particulate matter in the air on the surface of the filter membrane to achieve the measurement work of the instrument. Therefore, the shortcomings of the β-ray absorption method are that not only the single measurement time is long and continuous measurement is not possible, but also the more cumbersome maintenance work such as the need to periodically replace the filter membrane, which is not conducive to the long-...

AI Technical Summary

Problems solved by technology

Therefore, the defect of the β-ray absorption method is that not only the single measurement time is long and continuous measurement is not possible, but also the relatively cumbersome maintenance work such as regular replacement of the filter membrane is required, which is not conducive to the long-term online monitoring of the instrument sensor

The optical scattering method has a good response to particulate matter under various concentration conditions, and can measure continuously, but the sampling air pump used must be protected by a dust filter to work, so the dust filter needs to be replaced regularly, causing the instrument Large amount of maintenance, unable to work continuously for a long time

The cost of using an air suction pump is also high, and long-term use is likely to cause wear of the impeller, which affects the stability of the suction volume and the accuracy of the output data of the sensor

In addition, some existing optical scattering method sensors have mechanical flowmeters connected in series on the air path, which increases the resistance of the air path, thereby increasing the energy consumption of the air extraction device.

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