Lean burn internal combustion engine
US5067465A · kind A · utility
Assignees
Inventors
Key dates
| Filing date | Feb 14, 1991 |
| Grant date | Nov 26, 1991 |
| Priority date | — |
| Expiry date | Feb 14, 2011 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/1494
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A lean burn internal combustion engine wherein a basic fuel amount is calculated from a map based on the intake pressure and the engine speed, and a lean correction factor, which is multiplied by the basic fuel amount, is calculated from a lean map based on the intake pressure and engine speed. A second lean map based on the throttle opening and engine speed is provided for obtaining a lean correction factor when the degree of opening of the throttle valve is larger than a predetermined value. A lean sensor is provided for obtaining a signal indicating the air fuel ratio for carrying out a feedback control. The lean sensor is provided with a heater for controlling the temperature of the sensing element of the heater. A basic map for the heater power, which is based on the intake pressure and engine speed, is provided, and a correction map for the heater power is provided for reducing the heater power from the value obtained from the basic map when the lean map based on the intake pressure and engine speed is employed for obtaining the lean air-fuel mixture, to prevent thermal damage to the sensor element.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.