Abnormality detection system and abnormality detection method for internal combustion engine
US8171723B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 4, 2008 |
| Grant date | May 8, 2012 |
| Priority date | — |
| Expiry date | Sep 17, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
When the NOx SCR catalyst (15) deteriorates, the NOx removal efficiency increases with an increase in the catalyst temperature as indicated by the curves B1 and B2. When there is an irregularity in the amount or quality of aqueous urea solution that is supplied to the NOx SCR catalyst, the NOx removal efficiency decreases at a constant rate as indicated by the curve C. When the NOx removal efficiency is first within the region X2 and then brought into the region Y1, it is determined that the NOx SCR catalyst deteriorates. When the NOx removal efficiency is first within the region X2 and then brought into the region Y2, it is determined that there is an irregularity in the amount or quality of the aqueous urea solution that is supplied to the NOx SCR catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.