Patent · US Expired

Fiber optic flame and overheat sensing system with self test

US5064271A · kind A · utility

17Cited by
23References
10Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 14, 1989
Grant dateNov 12, 1991
Priority date
Expiry dateMar 14, 2009

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B17/12
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A fiber optic fire and overheat sensor system 10 includes a fiber optic cable 12 having a lens 14 at a distal to direct radiation from a fire 16 into the cable 12 and to a radiation detector 18 disposed at a proximal end of the cable 12. Detector 18 is coupled to a fire sensor 19. The detector 18 is sensitive to two wavelength bands including a short wavelength band of approximately 0.8 to approximately 1.1 microns and a long-wavelength band of approximately 1.8 to approximately 2.1 microns. A controller 21, such as a microprocessor, analyzes the fire sensor 19 output signals which correspond to the two spectral bands to determine if a fire is present. The system 10 further includes a body of fluorescent material 20 disposed at the distal end of the cable 12. The material 20 can be interposed between a reflecting surface, such as a mirror 22, and a lens, such as a collimating lens 24. A fiber optic coupler 26 and 26a launches radiation from a source 28, such as a laser diode, into the fiber optic cable 12. The fluorescent material is pumped by the source 28 at a first wavelength, the rate of decay of a resulting fluorescent emission being measured and correlated with predetermined …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.