Patent · US Expired

Fire detection system

US4149159A · kind A · utility

13Cited by
3References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateNov 11, 1977
Grant dateApr 10, 1979
Priority date
Expiry dateNov 11, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B17/00
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

In a fire detection system, detectors of different sensitivities are arranged in pairs and the pairs of fire detectors are positioned at regular intervals along an elongated protection area, whereby detectors of one sensitivity alternating with detectors of the other sensitivity are connected via two line systems to a signal center which emits an alarm signal when an alarm signal is simultaneously received via both line systems. In use, for example in a vehicle tunnel, a more uniform response sensitivity is obtained along the protection area, accompanied by a decrease in the necessary number of fire detectors and a reduced tendency to false alarms.

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