Engine exhaust purification device
US6622479B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 2001 |
| Grant date | Sep 23, 2003 |
| Priority date | — |
| Expiry date | Oct 16, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
A controller (6) computes the oxygen storage amount of the catalyst (3) separately as a high-speed component and a low speed component in accordance with actual characteristic. A target air-fuel ratio of an engine (1) is computed so that the oxygen storage amount is a predetermined target amount, and air-fuel ratio control of the engine (1) is performed. The oxygen storage amount is computed using an storage/release rate set according to the exhaust air-fuel ratio and catalyst temperature, etc. In this way, the oxygen storage amount of the catalyst can be precisely computed regardless of the variation in the storage/release rate which accompanies a catalyst temperature variation, and the real oxygen storage amount can therefore be controlled with a higher level of precision.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.