Air-fuel ratio control system for internal combustion engines and exhaust system temperature-estimating device applicable thereto
US5678402A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1995 |
| Grant date | Oct 21, 1997 |
| Priority date | — |
| Expiry date | Mar 23, 2015 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T10/40
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An air-fuel ratio control system for an internal combustion engine has a catalytic converter arranged in an exhaust passage. A maximum oxygen storage amount indicative of the maximum amount of oxygen that can be stored in the catalytic converter is calculated. The air-fuel ratio of a mixture supplied to the engine is forcibly oscillated at a predetermined frequency and a predetermined amplitude. At least one of the predetermined frequency and the predetermined amplitude is changed at a predetermined rate of change. A predetermined rate of change of the at least one of the predetermined frequency and the predetermined amplitude is set in dependence on the maximum oxygen storage amount to thereby secure the maximum purification rate of the catalytic converter.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.