Exhaust emission control system of diesel engine
US6742329B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Feb 28, 2003 |
| Grant date | Jun 1, 2004 |
| Priority date | — |
| Expiry date | Feb 28, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A HC adsorption type three-way catalytic converter is arranged in an exhaust gas passage of a diesel engine at a position upstream of a diesel particulate filter or a NOx trapping catalytic converter. Upon need of reactivation of the diesel particulate filter or NOx trapping catalytic converter under cold operation of the engine, a control unit carries out lowering an excess air ratio of the exhaust gas of the engine when the temperature of the catalyst bed of the three-way catalytic converter is lower than or equal to a first predetermined temperature (viz., oxidization activation temperature); raising the excess air ratio of the exhaust gas when the temperature of the catalyst bed of the three-way catalytic converter is higher than the first predetermined temperature but lower than or equal to a second predetermined temperature (viz., three-way catalyst activation temperature); and lowering the excess air ratio of the exhaust gas until the temperature of the exhaust gas purifying device becomes to a third predetermined temperature (viz., reactivation assuring temperature) when the temperature of the catalyst bed of the three-way catalytic converter is higher than the second prede…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.