Exhaust gas purification device of internal combustion engine
US8176730B2 · kind B2 · utility
Assignees
Inventors
Key dates
| Filing date | Jun 2, 2009 |
| Grant date | May 15, 2012 |
| Priority date | — |
| Expiry date | Mar 30, 2030 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/12
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An SCR catalyst is provided in an exhaust pipe of an engine and a urea solution addition valve is provided upstream of the SCR catalyst in the exhaust pipe. An ECU calculates ammonia adsorption quantity of the SCR catalyst and controls urea solution addition quantity, which is added by the urea solution addition valve, based on the ammonia adsorption quantity. The ECU obtains temperature of the SCR catalyst or temperature information correlated with the temperature through measurement or estimation. The ECU switches an execution mode of the urea solution addition control based on the catalyst temperature or the temperature information. Thus, reducing agent addition control can be performed suitably and eventually NOx purification in a NOx catalyst (i.e., SCR catalyst) can be performed suitably.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.