Exhaust gas purifying device for internal combustion engine
US8418438B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 13, 2010 |
| Grant date | Apr 16, 2013 |
| Priority date | — |
| Expiry date | Jul 1, 2031 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An exhaust gas purifying system for a diesel engine has an ECU, a passage of exhaust gas, a unit having SCR catalyst, a NOx sensor placed at a downstream side of the unit, and a urea water adding valve placed at an upstream side of the unit. The SCR catalyst in the unit selectively adsorbs ammonia, and selectively purifies NOx contained in an exhaust gas emitted from the diesel engine by the adsorbed ammonia. The ECU changes the urea water adding amount, and performs abnormality diagnosis based on the detection result of the NOx sensor while changing an adding amount of the urea water. The ECU uses a first condition to indicate the presence of an excess NOx amount in the exhaust gas, and a second condition to indicate there is no error cause by the ammonia adsorption on the SCR catalyst.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.