Exhaust gas purifying method of an internal combustion engine
US4375746A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jul 28, 1980 |
| Grant date | Mar 8, 1983 |
| Priority date | — |
| Expiry date | Jul 28, 2000 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02D41/1491
- WIPO fieldEnvironmental technology
- WIPO sectorChemistry
Abstract
An air-fuel ratio discrimination signal, having two voltage levels depending upon whether the air-fuel ratio of the engine is rich or lean in comparison with a predetermined air-fuel ratio, is generated in accordance with the sensed signal from a sensor which detects the concentration of a particular component in the exhaust gas. Then, the amount of secondary air supplied into the exhaust system of the engine is gradually increased or decreased in accordance with the level of the air-fuel ratio discrimination signal. Furthermore, the amount of secondary air supplied into the exhaust system is additionally increased or decreased in accordance with the average value of the air-fuel ratio discrimination signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.