Engine exhaust emission control
US6477833B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | May 16, 2001 |
| Grant date | Nov 12, 2002 |
| Priority date | — |
| Expiry date | May 16, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
An upstream catalyst (12) which stores oxygen in exhaust gas and releases the stored oxygen for oxidizing a reducing agent component contained in the exhaust gas, and a downstream catalyst (13) which stores nitrogen oxides in the exhaust gas and releases the stored nitrogen oxides by reducing the stored nitrogen oxides by the reducing agent component contained in the exhaust gas, are provided in an exhaust passage (11) of an engine (2). When the storage amount of nitrogen oxides of the downstream catalyst (13) reaches a predetermined value, additional fuel is injected from a fuel injector (7) after combustion, and stored oxygen in the upstream catalyst (12) is released by the reducing agent components in the additional fuel. After release of oxygen, the supply of the additional fuel is stopped and the supply of the main fuel is increased.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.