Exhaust gas-purifying device of an internal combustion engine
US4506644A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 5, 1983 |
| Grant date | Mar 26, 1985 |
| Priority date | — |
| Expiry date | Jan 5, 2003 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S261/56
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An engine comprising a variable venturi-type carburetor which has a raised wall formed on the inner wall of the intake passage thereof. The suction piston of the carburetor has a tip face having a V-shaped cross-sectional upstream end portion which cooperates with the raised wall for defining an approximately isosceles triangle-shaped airflow-restricting opening therebetween when the amount of air flowing within the intake passage is small. An electromagnetic valve is arranged in an air-bleed passage of the carburetor and is periodically opened at a fixed frequency of 1 to 2 Hz so that the air-fuel ratio fluctuates at a fixed frequency within the range of .+-.0.2 A/F unit through a .+-.1.0 A/F unit relative to an approximately stoichiometric air-fuel ratio.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.