Engine exhaust purification device
US6619032B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 16, 2001 |
| Grant date | Sep 16, 2003 |
| Priority date | — |
| Expiry date | Oct 16, 2021 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A microprocessor (6) computes an oxygen storage amount of a catalyst (3) separately for a high speed component and a low speed component in accordance with real characteristic. A target air-fuel ratio of an engine (1) is computed and air-fuel ratio control of the engine (1) it is performed so that the high speed component is constant. The deterioration of the catalyst (3) is determined by integrating the high speed component of the oxygen storage amount computed during the air-fuel ratio control process for a predetermined number of times, and comparing its average value with a determining value. The oxygen storage amount of the high speed component which is sensitive to catalyst deterioration is integrated so as to obtain a highly precise determining result to determine the deterioration.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.