Patent · US Expired

Flame detector

US4157506A · kind A · utility

123Cited by
5References
24Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 1, 1977
Grant dateJun 5, 1979
Priority date
Expiry dateDec 1, 1997

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG01R23/15
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

A method and apparatus for processing signals produced by a flame detector. A phase-locked loop is used to generate a binary indication of whether the signal from a flame probe is within a predetermined frequency band. A signal indicative of the average analog value of the resulting pulse train is produced and tested to determine whether it is in a range consistent with flame presence. The resultant binary signal is ANDed with a binary determination of whether the average DC value of the probe signal is within a range consistent with flame presence, and if both the DC and the frequency indications imply possible flame presence, then flame presence is indicated.

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