Exhaust gas purification device for an engine
US5388403A · kind A · utility
17Cited by
7References
10Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Feb 28, 1994 |
| Grant date | Feb 14, 1995 |
| Priority date | — |
| Expiry date | Feb 28, 2014 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An engine comprising an exhaust passage having therein a NO.sub.x absorbent which absorbs the NO.sub.x when the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorbent is lean and releases the absorbed NO.sub.x when the concentration of oxygen in the exhaust gas is lowered. When the air-fuel ratio of air-fuel mixture fed into the engine cylinder is made a rich air-fuel ratio or the stoichiometric air-fuel ratio, a secondary air is fed into the exhaust passage upstream of the NO.sub.x absorbent to make the air-fuel ratio of exhaust gas lean.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.