Low evaporative emission fuel system depressurization via solenoid valve
US7066152B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 2004 |
| Grant date | Jun 27, 2006 |
| Priority date | — |
| Expiry date | Oct 29, 2024 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M63/0215
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A fuel delivery system is provided with a fuel solenoid valve to minimize fuel leakage and evaporative emissions during diurnal cycles by preventing pressure buildup as the temperature of the fuel system rises. The fuel solenoid valve is located between a pressurized side of the delivery system and a fuel tank. In one embodiment, the fuel solenoid valve is closed when the engine is running or when the engine is off and the rail is hot. When the fuel rail cools down, the solenoid valve opens to bleed a desired amount of fuel thereby creating a fuel vapor space. Thereafter, during hot soak conditions of the diurnal cycles when the fuel rail is hot again while the engine is off, the pressure will rise due to the thermal expansion of the fuel and the created fuel vapor space minimizes further rising of the fuel pressure. Further, by adjusting the solenoid valve opening time, the pressure rising limit may be set at a desired pressure to minimize injector leakage.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.