Communications: electrical – Condition responsive indicating system – Specific condition
Patent
1980-01-08
1981-10-27
Kaplan, G. L.
Communications: electrical
Condition responsive indicating system
Specific condition
204195R, 204195P, G01N 2746, G01N 2754, G08B 2300
Patent
active
042976898
ABSTRACT:
A dosimeter includes an electrochemical sensing cell and circuitry which provides a first alarm when the contaminant concentration exceeds a short-term exposure limit, and a second alarm when the time weighted average concentration level over a relatively longer term exceeds a different threshold limit value. In one sensing cell embodiment, the gas sample flows through a circuitous recess on the interior surface of the cell body, which recess is covered by the sensing electrode. A downstream pump urges the gas sample through the cell. In an alternative embodiment, not utilizing a pump, the gas sample enters the cell by diffusing through a sintered porous plate into contact with the sensing electrode. In each cell, the output current is proportional to the contaminant concentration level.
To obtain a time weighted concentration level alarm signal, the circuitry employs a frequency converter that produces output pulses at a rate proportional to the cell output current level. These pulses are counted. The alarm signal is produced when the count reaches a value C=LnT, where n is the frequency converter output in pulses per second for a concentration of 1 ppm, T is a certain extended time duration, and L is the threshold limit value.
REFERENCES:
patent: 3515658 (1970-06-01), Amdur
patent: 3574048 (1971-04-01), Hynes et al.
patent: 3776832 (1973-12-01), Oswin et al.
patent: 4013522 (1977-03-01), Nischik et al.
patent: 4029563 (1977-06-01), Binder et al.
patent: 4132616 (1979-01-01), Tantram et al.
patent: 4152233 (1979-05-01), Chand
patent: 4169779 (1979-10-01), Tataria et al.
patent: 4182666 (1980-01-01), Dickinson et al.
patent: 4231249 (1980-11-01), Zuckerman
Unico Carbon Monoxide Detector & Alarm.
Shaw Manuel
Thatcher Imbrie
Interscan Corporation
Kaplan G. L.
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