Air-fuel ratio feedback control apparatus
US6739122B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 2002 |
| Grant date | May 25, 2004 |
| Priority date | — |
| Expiry date | Jul 17, 2022 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
The present invention provides an air-fuel ratio feedback control apparatus for an internal-combustion engine. The apparatus includes an air-fuel ratio detector that is disposed in an exhaust system of the engine so as to detect an air-fuel ratio of exhaust gas, NOx purifier for purifying NOx contained in the exhaust gas during a lean operation and feedback controller for making a feedback control upon an air-fuel ratio of air-fuel mixture to be supplied to the engine based on an output of the air-fuel ratio detector. A diagnostic system diagnoses the NOx purifier based on an output of an O2 sensor disposed downstream of the NOx purifier when the air-fuel ratio of the air-fuel mixture to be supplied to the engine has been changed from lean to rich and gain changer for making a feedback control gain of the feedback controller smaller when the air-fuel ratio is changed from lean to rich.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.