Exhaust gas purification system for an internal combustion engine
US8402753B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 26, 2008 |
| Grant date | Mar 26, 2013 |
| Priority date | — |
| Expiry date | May 13, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
This invention is to reduce NOx occluded in a NOx catalyst in a more appropriate manner. In this invention, in case where an amount of NOx occluded when an execution condition for NOx reduction control holds is more than a predetermined amount of occlusion, NOx reduction control is performed by lowering the O2 concentration of the exhaust gas by means of said O2 concentration lowering means and at the same time supplying a reducing agent to the NOx catalyst by a reducing agent supplying means. In addition, in case where the amount of NOx occluded when the execution condition for NOx reduction control holds is equal to or less than the predetermined amount of occlusion, NOx reduction control is executed by supplying the reducing agent to the NOx catalyst by the reducing agent supplying means without lowering the O2 concentration of the exhaust gas by the O2 concentration lowering means.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.