2 STAGE ISOKINETIC CONTROL UNIT FOR DUST CONCENTRATION MEASUREMENTS DEVICE

摘要

PURPOSE: A two stag isokinetic control device for measuring dust density is provided to rapidly measure dust density on a highway or the center of a town by implementing an isokinetic absorption to maintain a sample input speed to be equal to the moving speed of a vehicle or gas. CONSTITUTION: A slope tubular plenum part(120) has a hollow part and is connected to a first nozzle(110). A second nozzle(124) is installed in the slope tubular plenum part and reabsorbs samples absorbed by the first nozzle. A flux control unit(130) is connected to the plenum part and controls the speed of the absorbed samples. A location control unit(140) is horizontally transferred according to a driving speed of a vehicle and controls an absorption location of the second nozzle. [Reference numerals] (AA) Flow control circuit; (BB) Location control circuit