Evaporative emissions control for carburetors
US5943997A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Feb 6, 1998 |
| Grant date | Aug 31, 1999 |
| Priority date | — |
| Expiry date | Feb 6, 2018 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S261/67
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
An evaporative emissions control system for carburetors used in the internal combustion engines of vehicles, such as motorcycles, has an evaporative emissions control valve attached to the carburetor in the air intake path to the carburetor. The evaporative emissions control valve may be implemented as a sub-assembly add-on or as an integral part of a carburetor or back plate. The evaporative emissions control valve includes a valve, such as a rotatable plate valve, which may be electrically operated by an electrical actuator, such as a dual-wound solenoid actuator. At engine start-up, when the vehicle ignition switch and starter switch are both closed, both windings of the solenoid actuator are energized to provide a strong opening force for the evaporative emission control valve. During steady-state running of the engine, only a single solenoid winding is energized by the power provided through the ignition switch, to maintain the evaporative emissions control valve in the open position. When the ignition switch is opened and the engine is turned off, the evaporative emissions control valve is closed to prevent the release of fuel vapors from the carburetor. A vacuum controlled s…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.