Air/fuel ratio control system for internal combustion engine
US6334425B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 27, 2000 |
| Grant date | Jan 1, 2002 |
| Priority date | — |
| Expiry date | Apr 27, 2020 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2200/0411
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An air/fuel ratio control system for a direct injection spark ignition internal combustion engine which is operated at an ultra-lean burn combustion or at a pre-mixture charged combustion. In the system, a charging efficiency correction coefficient for adjusting a charging efficiency of intake air is determined based at least on the determined desired air/fuel ratio and the form of combustion, and the desired air/fuel ratio is corrected by the coefficient. Then, the output fuel injection amount is determined based at least on the basic fuel injection amount and the corrected desired air/fuel ratio (desired air/fuel ratio correction coefficient). The charging efficiency correction coefficient is determined to be a less value when the engine is operated at the ultra-lean burn combustion than that when the engine is operated at the pre-mixture charged combustion. The coefficient is made different whether or not the operation of EGR is progress. With this, the desired air/fuel ratio is determined adequately and hence, the fuel injection amount can be determined adequately.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.