Oxygen sensor for air-fuel ratio control having a protective layer including an oxygen storage material
US5160598A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 14, 1990 |
| Grant date | Nov 3, 1992 |
| Priority date | — |
| Expiry date | Feb 14, 2010 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01N27/4078
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
Oxygen sensor for air-fuel ratio control is provided with a sensor element having an oxygen ion-conductive main body and electrodes on both sides thereof, and at least one porous protective layer covering the electrode on the exhaust gas side. The protective layer includes an oxygen storage component OSC without copresence of a noble metal catalyst. The protective layer is intermeshingly connected to the main body via spherical protrusions of the main body. Double-layered protective layer structure includes OSC noncontaining layer (optionally containing catalyst) and OSC containing layer, as inner and outer protective layer or vice versa. OSC containing layer is formed by impregnation with OSC-solution through immersing the respective porous protective layer, or by cosintering the OSC containing green coating layer. By impregnation 0.2 -8 wt %, or by cosintering 0.2-30 wt %, of OSC metal element is containable. The outer protective layer is thinner and more porous than the inner protective layer. Any of the protective layers can be formed by flame spraying.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.