Device for measuring a component of a gaseous mixture
US4905652A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 30, 1989 |
| Grant date | Mar 6, 1990 |
| Priority date | — |
| Expiry date | May 30, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/4065
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A device for detecting and measuring the concentration of a gas in a mixture of gas such as oxygen in the exhaust gas of an internal combustion engine and circuits for using that measurement to control the air-fuel ratio supplied to the engine. The detecting device has two separate gas residence chamber with different diffusion resistance openings for each chamber and separate pairs of electrodes for each chamber whereby the measurement can be separately made in each chamber. The particular chamber selected for measurement may be done on the basis of whether the air-fuel ratio is lean or rich whereby a substantially linear reading results for all ratios or on the basis of the transition-state or steady-state operating condition of the engine to provide either more rapid or more accurate readings. Further, by using the cells from both chambers to compare their readings and standards, the actual readings can be corrected for abnormalties that may occur after a period of use or to indicate the detector has become defective.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.