Exhaust emission control device of internal combustion engine
US6463734B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 30, 2000 |
| Grant date | Oct 15, 2002 |
| Priority date | — |
| Expiry date | Aug 30, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An exhaust emission control device of an internal combustion engine, which purifies exhaust gas exhausted from the internal combustion engine, comprises: a catalyst device composed of a three way catalyst for purifying harmful substance in the exhaust gas when an exhaust air-fuel ratio is substantially stoichiometrical and an NOx catalyst having a function of absorbing NOx in the exhaust gas when the air-fuel ratio is closer to a lean air-fuel ratio than to the stoichiometrical air-fuel ratio, the catalyst device being provided in an exhaust passage of the internal combustion engine; catalyst deterioration determination means for determining deterioration state of the catalyst device, the deterioration resulting from at least temperature; and control means for deteriorating exhaust gas components flowing into the catalyst device much more than exhaust gas components flowing into the catalyst device when an air-fuel ratio of a mixture supplied to the internal combustion engine is substantially stoichiometrical, if the catalyst deterioration determination means determines that the catalyst device is in a predetermined deterioration state. The deterioration of an NOx absorbing functio…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.