Exhaust gas purifying apparatus and method for internal combustion engine, and engine control unit
US7204081B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 24, 2003 |
| Grant date | Apr 17, 2007 |
| Priority date | — |
| Expiry date | Mar 13, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An exhaust gas purifying apparatus and method for an internal combustion engine, and an engine control unit are provided for appropriately determining the amount of reducing agent supplied to a NOx selective reduction catalyst to ensure good exhaust gas characteristics. The exhaust gas purifying apparatus comprises an ECU; a NOx selective reduction catalyst for purifying NOx in exhaust gases in an exhaust pipe; a NOx sensor disposed in the exhaust pipe at a location downstream of the NOx selective reduction catalyst for detecting a NOx concentration in exhaust gases; and an injector for supplying the NOx selective reduction catalyst with ammonia produced in an ammonia production unit. The ECU determines the amount of ammonia injected to the NOx selective reduction catalyst by the injector such that an estimate of the NOx concentration detected by the NOx sensor reaches a minimum value.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.