Degradation diagnostic apparatus for NOx catalyst
US9021789B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Mar 6, 2008 |
| Grant date | May 5, 2015 |
| Priority date | — |
| Expiry date | Oct 31, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
A NOx amount capable of being absorbed by a criteria catalyst as a boundary between degradation and normality is supplied to a NOx storage reduction catalyst and thereafter, a reducer amount corresponding to the NOx amount is supplied by a rich spike operation. Degradation of the NOx catalyst is determined based upon the output of the NOx sensor at this time. Since the degradation of the NOx catalyst is determined only by a magnitude of the NOx sensor output, the degradation diagnosis can be performed with high precision. While the catalyst is normal, the excessive reducers are not supplied and therefore, deterioration of the fuel consumption can be prevented.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.