Air-fuel ratio feedback control system for internal combustion engine
US5531208A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 13, 1994 |
| Grant date | Jul 2, 1996 |
| Priority date | — |
| Expiry date | Sep 13, 2014 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2041/1433
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A system for controlling an air-fuel ratio of an air-fuel mixture supplied to each cylinder of a multicylinder internal combustion engine. A first feedback loop is provided for converging a first air-fuel ratio at a location at least either at or downstream of a confluence point of an exhaust system to a first desired air-fuel ratio by multiplying a first feedback gain to a first error therebetween. And a second feedback loop is provided in the first loop for converging a second current air-fuel ratio at each cylinder to a second desired air-fuel ratio by multiplying a second feedback gain to a second error. The first feedback loop and said second feedback loop are connected in series such that the second loop located inside the first loop. With the arrangement. the second loop operates the second air-fuel ratio converges to converge the second air-fuel ratio to the first air-fuel ratio which in turn tends to converge on the first desired air-fuel ratio such that the air-fuel ratios of all cylinders can therefore be converged on the desired air-fuel ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.