Air fuel ratio control system for variable valve timing type internal combustion engines
US5199403A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 9, 1992 |
| Grant date | Apr 6, 1993 |
| Priority date | — |
| Expiry date | Jul 9, 2012 |
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 having at least one intake valve with its valve timing changeable at least between low-speed valve timing suitable for engine operation in a low engine rotational speed region, and high-speed valve timing suitable for engine operation in a high engine rotational speed region. When changeover is to be effected from the low-speed valve timing to the high-speed valve timing, an ECU changes the desired air-fuel ratio to be applied when the low-speed valve timing is selected, to one to be applied when the high-speed valve timing is selected, and changes the valve timing to the high-speed valve timing after the desired air-fuel ratio has been changed to the one to be applied when the high-speed valve timing is selected.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.