Dust concentration meter

Abstract

Abstract PURPOSE: To reduce the zero drift the dust mass value, by keeping the temperature of air layer between the radio isotope and the raidoactive ray detector constant. CONSTITUTION: By adding the heater 8, temperature sensor such as thermister 9 and temperature control circuit 10, the temperature of air layer between the radio isotope 5 and the radioactive ray detector 6 can be controlled constantly. Thus, after collecting the dust contained on the filter paper 2 by the dust collector 1 and sampled with the sample gas suction pump 11, this gas is introduced to the gas meter 12 to measure the integrated flow. The filter paper 2 containing dust is carrid right with the revolution of the motor reels 3, 3', and the B ray intensity transmitting the dust is measured at the radioactive ray detector 6. The measurement and the transmitted B ray intensity before dust collection are inputted to the logarithmic operation 7 to obtain the mass of dust. The dust concentration can be determined by this and the integrated flow. Further, by keeping constant the temperature of the air layer between the radio isotope 5 and the radioactive ray detector 6, the zero drift of the dust mass value based on the mass change of the air layer can be reduced. COPYRIGHT: (C)1980,JPO&Japio

Inventors

• 👤 Hideo Takeuchi

Bibliographic Details