Method and apparatus for monitoring catalyst efficiency and outlet oxygen sensor performance
US6868666B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 2003 |
| Grant date | Mar 22, 2005 |
| Priority date | — |
| Expiry date | Apr 8, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A vehicle exhaust system includes a catalytic converter and an outlet sensor. The outlet sensor generates a sensor signal based on an oxygen level of exhaust gases exiting the catalytic converter. A controller communicates with an engine and the outlet sensor, and monitors the sensor signal during a predetermined period of engine operation. The controller commands an intrusive catalyst monitor test in a default order if the outlet sensor signal transitions through both thresholds during a predetermined period. The controller performs an intrusive outlet sensor test during cruise operation of the engine if the signal fails to transition through both thresholds during the catalyst monitor test.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.