Oxygen storage control of engine exhaust gas purification catalyst
US6718754B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 24, 2002 |
| Grant date | Apr 13, 2004 |
| Priority date | — |
| Expiry date | Jul 24, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A three-way catalyst (10) is provided in the exhaust passage (9) of an engine (1) which stores and releases oxygen according to the oxygen concentration in the exhaust gas. A controller (2) calculates an oxygen storage amount of the catalyst (10) by accumulating a variation rate of the oxygen storage amount of the catalyst (10) based on the oxygen amount in the exhaust gas (S3-S5). A target oxygen amount in the exhaust gas is calculated which reduces the difference of the oxygen storage amount from a target oxygen storage amount (S6). A target air/fuel ratio is calculated based on a catalyst deterioration coefficient, an exhaust gas flowrate and the target oxygen amount (S7). Due to this process, it is possible to increase the speed and accuracy of control of the oxygen storage amount of the catalyst (10) towards the target oxygen storage amount.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.