Exhaust gas purifying system for internal combustion engine
US7797925B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 14, 2006 |
| Grant date | Sep 21, 2010 |
| Priority date | — |
| Expiry date | May 18, 2029 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF01N3/18
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An NOx catalytic converter, which includes an NOx storage and reduction catalyst, absorbs NOx contained in exhaust gas of an engine. The absorbed NOx is deoxidized and eliminated when an NOx deoxidizing agent is supplied to the catalytic converter. An ECU determines a purifying performance of the catalytic converter based on one of an amount of supplied NOx deoxidizing agent, which is required to deoxidize and remove absorbed NOx at the NOx catalytic converter, and a parameter that correlates with the amount of the supplied NOx deoxidizing agent. The ECU prohibits the determining of the purifying performance of the catalytic converter when it is determined that supplied unburnt fuel, which is supplied to the catalytic converter, is in an excessive state.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.