Gas component detection apparatus
US4244918A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Apr 24, 1978 |
| Grant date | Jan 13, 1981 |
| Priority date | — |
| Expiry date | Apr 24, 1998 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N33/0031
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A gas component detection apparatus comprises a first and a second gas sensing elements each composed of a metal oxide which exhibits variable electric resistances according to gaseous components and temperatures of gases to be detected. A catalyst is carried at least by the first sensing element for promoting oxidation reactions of the gaseous components of the gases. A first pair of electrodes are inserted into those portions of the first sensing element which are subjected to catalytic action of the catalyst. Into the portions of the second sensing element which are not subjected to catalytic action are inserted a second pair of electrodes. The first pair of electrodes sense a variation in electric resistances resulting from the gaseous components and temperatures of the gases, while the second pair of electrodes detect an electric resistance variation related mainly upon the gas temperatures. Consequently, an output signal reflecting substantially only the gaseous components of the gases is produced by offsetting both of the electric resistances separately sensed utilizing a suitable electric circuit.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.