Method and system for determining and controlling A/F ratio during cold start engine operation
US5915359A · kind A · utility
19Cited by
7References
20Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | May 5, 1997 |
| Grant date | Jun 29, 1999 |
| Priority date | — |
| Expiry date | May 5, 2017 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D2041/1433
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A method and system for determining and controlling air/fuel ratio during engine cold start operation relies on applying a monotonically decreasing fuel pulse width modulation to the engine and synchronously measuring the effect of the modulation on related engine event periods. This effect is utilized in estimating air/fuel ratio, which is then compared to the desired air/fuel ratio. The difference between the estimated air/fuel ratio and the desired air/fuel ratio is used in controlling the air/fuel ratio to the desired air/fuel ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.