Air/fuel ratio feedback control system adapted to temporary open-loop control under transient conditions
US4706633A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Apr 14, 1986 |
| Grant date | Nov 17, 1987 |
| Priority date | — |
| Expiry date | Apr 14, 2006 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/068
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
This invention relates to a control system for feedback control of the air/fuel ratio in an internal combustion engine, which may be an automotive engine, by using an oxygen sensor to detect actual values of the air/fuel ratio from the concentrations of oxygen in the exhaust gas. The control system has the function of temporarily shifting the feedback control of air/fuel ratio to open-loop control when any of predetermined transient operating conditions of the engine is detected. To resume the temporarily interrupted feedback control at an optimum time-point, the air/fuel ratio control system includes means to detect the degree of warm-up of the engine and means to variably determine the duration of the temporary open-loop control according to the detected degree of warm-up of the engine.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.