Smoke detector with means for changing light pulse frequency

Details Smoke detector with means for changing light pulse frequency Smoke detector with means for changing light pulse frequency

1976-11-16

1978-01-10

Nelms, David C.

Radiant energy

Photocells; circuits and apparatus

Optical or pre-photocell system

340237S, G01N 2126

Patent

active

040681300

ABSTRACT:
A smoke detector operating on the reflected light principle, utilizing a pulsing light source and means requiring several consecutive pulses of light reflected from smoke to actuate an alarm. During normal standby operation, the light pulses at a predetermined slow rate. When smoke is present, the first pulse of light reflected from the smoke causes the pulse rate to increase for a predetermined number of pulses or for a predetermined short time, so that the number of reflected pulses required to actuate the alarm are received in a shorter time. The time to alarm is thereby shortened without increasing the current drain of the device and without shortening the life of the pulsing light source.

REFERENCES:
patent: 3711210 (1973-01-01), Krukowski
patent: 3936814 (1976-02-01), Muller-Girard
patent: 4024407 (1977-05-01), Meric

Affiliated with

Also associated with

Rating

Smoke detector with means for changing light pulse frequency does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Smoke detector with means for changing light pulse frequency, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Smoke detector with means for changing light pulse frequency will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-2273143