System and method to reduce fuel system pumping heat input
US7252068B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 24, 2005 |
| Grant date | Aug 7, 2007 |
| Priority date | — |
| Expiry date | May 10, 2025 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY02T50/60
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
The present invention discloses a relatively simple system and method to reduce fuel system pumping by automatically turning on and off servo flow to various non-needed devices or “start lockout” servos during engine start. The invention takes advantage of a fuel pressure rise provided by the fuel pump during the period from engine start until the pump speed is greater than windmill. This pressure rise is used to move a pressure activated piston in a servo shutoff valve from a normally closed position to an open position, which at higher pressures allow servo flow to the “start lockout” servos through the servo lockout valve. When the pressure is reduce, the piston return to a normally closed position due to a biasing spring closing the servo lockout valve. This opening and closing of the servo lockout valve occurs automatically with no other external input.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.