Exhaust discharge control device for internal combustion engine
US6233925A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 5, 1999 |
| Grant date | May 22, 2001 |
| Priority date | — |
| Expiry date | Aug 5, 2019 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2200/0804
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An NO.sub.x absorbent is arranged in an engine exhaust passage absorbs NO.sub.x when the air-fuel ratio of inflowing exhaust gas is lean and discharges absorbed NO.sub.x or SO.sub.x when the oxygen concentration of inflowing exhaust gas decreases. When the air-fuel ratio of the exhaust gas flowing into the NO.sub.x absorbent is rich, previously absorbed NO.sub.x or SO.sub.x is discharged from the NO.sub.x absorbent. When NO.sub.x or SO.sub.x is to be discharged from the NO.sub.x absorbent, oxygen is left in the exhaust gas flowing into the NO.sub.x absorbent and the oxygen concentration of this exhaust gas is maintained within a predetermined range.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.