Radiant energy – Photocells; circuits and apparatus – Optical or pre-photocell system
Patent
1991-12-20
1993-06-15
Nelms, David C.
Radiant energy
Photocells; circuits and apparatus
Optical or pre-photocell system
367906, 25023119, H01J 516
Patent
active
052201600
ABSTRACT:
A fiber optic-type shock wave sensor automatically adapts itself in response to vibration preventing false shock wave detection signals. The sensor includes a sensor element comprising a pair of mating toothed rings and a fiber optic coil disposed between the teeth of the rings. One of the toothed rings is moveable in response to shock waves to cause a bending of the fiber optic coil which detectably alters its light transmission characteristics. A rigid, dome shaped membrane is attached to the moveable ring and is flexibly attached to a body containing the sensor element. The membrane and body form an enclosure for the sensor element, and an aperture is disposed in the body which communicates with the enclosure. A normally closed spring biased check valve covers the aperture, and opens in response to a reduction in pressure in the enclosure to admit additional air or gas to the same. When the sensor is exposed to vibration, the membrane moves back and forth, thereby causing the check valve to cycle open and closed. This results in a pumping effect which draws additional air or gas into the sealed enclosure, and the membrane is caused to move outwardly away from the sensor body. This both causes the membrane to stiffen and its natural frequency to be shifted so that the membrane and moveable ring will be effectively insulated from the resonance effects of vibration, and the sensor will therefore not generate a false shock wave detection signal in response to vibration.
REFERENCES:
patent: 4351026 (1982-09-01), Phillips
patent: 4408829 (1983-10-01), Fitzgerald et al.
patent: 4421979 (1983-12-01), Asawa et al.
patent: 4436995 (1984-03-01), Whitten
patent: 4472628 (1984-09-01), Whitten
patent: 4667097 (1987-05-01), Fasching et al.
patent: 4770047 (1988-09-01), Arditty et al.
patent: 4800267 (1989-01-01), Freal et al.
patent: 4860586 (1989-08-01), Miers et al.
patent: 4918305 (1990-04-01), Wlodarczyk et al.
patent: 5025424 (1991-06-01), Rohrbaugh
Cornell Research Foundation Inc.
Nelms David C.
LandOfFree
Adaptive fiber optic shock wave sensor does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Adaptive fiber optic shock wave sensor, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Adaptive fiber optic shock wave sensor will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1045173