Particulate products of combustion detector employing solid stat

Details Particulate products of combustion detector employing solid stat Particulate products of combustion detector employing solid stat

1976-07-08

1978-05-02

Caldwell, Sr., John W.

Communications: electrical

Systems

Call station

250574, G08B 1710

Patent

active

040877990

ABSTRACT:
A particulate products of combustion detector having a light emitting diode and a photovoltaic solar cell coupled one to the other to serve as a particulate or smoke sensor. A free-running multivibrator periodically pulses the light emitting diode to corresponding pulses of light emission having a first pulse-repetition frequency of about 80 Hz. and a duty cycle of about five percent. The output of the solar cell is connected to the input of a ringing amplifier to generate at the amplifier output a ringing pulse sequence having the same pulse-repetition frequency as that of the light element emissions in response to the detection of the particulate products of combustion. The ringing amplifier has a passband of about 500 Hz. centered about a frequency of about 1000 Hz. A detector is connected to the output of the ringing amplifier to generate a peak voltage responsive and proportional to the greatest voltage amplitude of each ringing pulse, namely, that of the first half-cycle of each ringing pulse. A bistable flip-flop is connected to the output of the peak voltage detector. When a peak voltage greater than a threshold magnitude is applied to the flip-flop indicative of the detection of the products of combustion, the circuit is driven to its second stable state, thereby actuating a smoke alarm relay.

REFERENCES:
patent: 3316410 (1967-04-01), Meili et al.
patent: 3946241 (1976-03-01), Malinowski

Affiliated with

Also associated with

Rating

Particulate products of combustion detector employing solid stat does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Particulate products of combustion detector employing solid stat, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Particulate products of combustion detector employing solid stat will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2161549