Exhaust purification device of internal combustion engine
US8117834B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 23, 2008 |
| Grant date | Feb 21, 2012 |
| Priority date | — |
| Expiry date | Sep 11, 2029 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T137/7287
- WIPO fieldChemical engineering
- WIPO sectorChemistry
Abstract
In an internal combustion engine, an NOx selective reduction catalyst is arranged in the engine exhaust passage and a urea aqueous solution stored in a urea aqueous solution tank is fed to the NOx selective reduction catalyst where the NOx is selectively reduced. Opening and closing of the urea aqueous solution refill port of the urea aqueous solution tank are detected and it is judged if the urea aqueous solution is refilled in the urea aqueous solution tank. When it is judged that the NOx purification rate has fallen to an allowable level or less at the time of engine operation right after the urea aqueous solution is refilled in the urea aqueous solution tank, it is judged that the refilled urea aqueous solution is abnormal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.