Patent · US Expired

Alarm detector responsive to rate change of a monitored condition

US4300048A · kind A · utility

32Cited by
1References
3Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJun 27, 1979
Grant dateNov 10, 1981
Priority date
Expiry dateJun 27, 1999

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B17/06
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

A physical quantity such as temperature, infrared radiation or smoke is detected by means of a conversion device for emitting an alarm signal whose amplitude is representative of the intensity of the physical quantity. The detector comprises a unit for measuring relative variations of the signal in time, for comparing them with a preset threshold level and for actuating the alarm when they exceed the threshold level.

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