Patent · US Expired

Electrode insulating member for ionization fire alarm

US4582996A · kind A · utility

2Cited by
4References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 21, 1983
Grant dateApr 15, 1986
Priority date
Expiry dateMar 21, 2003

Classification

  • Technology area (CPC G)Physics
  • CPC primaryG08B17/113
  • WIPO fieldControl
  • WIPO sectorInstruments

Abstract

Due to aging of the insulating materials arranged between the electrodes in ionization fire alarms or detectors the insulating efficiency of these thus formed so-called insulating paths or spans deteriorates in the course of time despite, or maybe even due to the cleaning operations performed upon such ionization fire alarms. To ensure that the insulating capacity does not fall below a critical value the insulating path or span is formed by at least two different insulating materials. The materials are arranged in such a manner that the creepage path between the electrodes extends across all the different insulating materials. This principle also may be applied to other measuring devices which require a high input resistance of an amplifier stage.

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