Air/fuel ratio detector
US4578172A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Dec 13, 1984 |
| Grant date | Mar 25, 1986 |
| Priority date | — |
| Expiry date | Dec 13, 2004 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/4065
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
An air/fuel ratio detector capable of producing an unambiguous output for both fuel-rich and fuel-lean regions. A solid-electrolyte oxygen-concentration-difference-actuated electrochemical cell sensor element is provided having a porous electrode formed on both sides of an oxygen-ion-conductive solid electrolyte. A solid-electrolyte oxygen pump element is also provided with a porous electrode formed on both sides of an oxygen-ion-conductive solid electrolyte. An oxygen reference element has a metal oxide semiconductor layer formed on one side of a substrate made of an air-impermeable member. The electrochemical cell sensor element and the pump element are disposed facing one another with a small gap therebetween. An air compartment open to the atmosphere is formed between that side of the pump element opposite the side facing the small gap and the side of the reference element opposite the side having the metal oxide semiconductor layer. The air/fuel ratio is detected both by a change in the electrical properties of the oxygen reference element and by output signal provided by at least one of the electromotive force of the electrochemical cell sensor element and a pump current flow…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.