Communications: electrical – Systems – Call station
Patent
1974-10-30
1976-04-13
Caldwell, John W.
Communications: electrical
Systems
Call station
340237S, G08B 1710
Patent
active
039507394
ABSTRACT:
The invention involves an apparatus and method. It has for a purpose the detection of a contaminating gas or smoke in the free and unconfined atmosphere and for locating the source of the contamination. A specific use is to detect leaks in systems containing gas under pressure. The apparatus comprises a sensor in the form of a semi-conductor material, whose conductance varies with variations in the density of the contaminant in the region immediately surrounding the sensor. The sensor is connected to the input circuit of an amplifier, which operates to produce a voltage that varies with the conductance of the sensor. For producing an indication of the presence of the contaminating gas and also its density, a pulse generator is connected to and controlled by the voltage output of the amplifier, whereby, as the voltage of the output of the amplifier varies, the frequency of the pulses of the pulse generator also varies. A visual indicator in the form of a light emitting diode is connected to the output of the pulse generator from which a pulsating light is produced which varies in step with the output of the pulse generator. An audible indicator is also provided, which is a tone whose pitch varies with changes in density, which is pulsed at a frequency which also varies in frequency with changes in density of the contaminant. For this purpose, an audio frequency oscillator is connected to the output of the amplifier whereby an audio frequency voltage is produced which varies with the voltage at the output of the amplifier. A speaker is used for converting the audio frequency voltage into a tone whose pitch varies with the audio frequency voltage. A gating device under the control of the pulse generator connects the audio frequency generator to the speaker, which produces the pulsations in the audible signal. The method comprises the steps that are performed by the apparatus for sensing the gas or smoke and producing an indication of its presence and change in density.
REFERENCES:
patent: 2499806 (1950-03-01), Wouk et al.
patent: 3686655 (1972-08-01), Kasahara
patent: 3786462 (1974-01-01), Hayden
patent: 3879717 (1975-04-01), Gruensfelder
Caldwell John W.
Myer Daniel
LandOfFree
Detector for detecting and locating the source of a contaminatin does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Detector for detecting and locating the source of a contaminatin, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Detector for detecting and locating the source of a contaminatin will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-755105