Engine exhaust gas purifying apparatus
US6357224B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 12, 2000 |
| Grant date | Mar 19, 2002 |
| Priority date | — |
| Expiry date | Jun 12, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
The invention provides a method of controlling an air-fuel ratio and for diagnosing a deterioration of a catalyst having an NOx trapping agent in an internal combustion engine. An exhaust gas purifying apparatus having an NOx trapping agent arranged within an exhaust gas passage, an air-fuel ratio changing means temporarily changing the air-fuel ratio of the exhaust gas from the lean to the stoichiometric or rich air-fuel ratio at a predetermined cycle, a particular component detecting means detecting a particular component in the exhaust gas downstream the NOx trapping agent, a NOx discharge or reduction completion judging means, and NOx discharge or reduction completion time detecting means detecting a time required for purifying the NOx.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.