Apparatus for detecting combustible gases
US4045177A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Aug 16, 1976 |
| Grant date | Aug 30, 1977 |
| Priority date | — |
| Expiry date | Aug 16, 1996 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/16
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
This is an improvement in apparatus for detecting combustible gases, such as methane, that embodies a Wheatstone bridge circuit including a refractory-coated reference element constituting one leg of the bridge and a refractory-coated detector element having thereon a catalyst for promoting oxidation of the combustible gas to be detected constituting a second leg of the bridge. Upon oxidation of combustible gas at the detector element the temperature and resistance thereof increases relative to the reference element to unbalance the bridge, thereby producing an electrical signal proportional to the amount of combustible gas being oxidized. This invention improves the stability, linearity, and stabilization time of the bridge signal by constructing the reference element so that at zero percent combustible gas or during oxidation of the combustible gas at the detector element the radiant energy of both the detector and reference element are substantially equal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.