Exhaust emission control device for internal combustion engine
US6263666A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 16, 2000 |
| Grant date | Jul 24, 2001 |
| Priority date | — |
| Expiry date | Mar 16, 2020 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An exhaust emission control device of an engine 1 comprises an NOx storage catalyst 9 which traps and stores NOx in exhaust gas and reduces the stored NOx according to an air fuel ratio of inflowing exhaust gas. A controller 6 determines conditions for discharging the SOx stored in the catalyst 9. When SOx discharge conditions are satisfied and the engine running conditions are in a predetermined SOx discharge running region, the controller 6 performs SOx discharge control of the catalyst 9. As lean air fuel ratio control is prohibited from when SOx discharge conditions are satisfied to when SOx discharge is complete, lean air fuel ratio control is prevented from taking place when the NOx trapping capacity of the catalyst 9 is insufficient, and increase of exhaust emission is thereby prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.