Variable injection rate high pressure fuel pump
US6726459B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Nov 7, 2002 |
| Grant date | Apr 27, 2004 |
| Priority date | — |
| Expiry date | Nov 7, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M59/26
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A high pressure fuel pump having a variable fuel injection rate, including a pump body, a pump cylinder formed in the pump body and a piston reciprocable within the pump cylinder, which defines a pressurization chamber. The pump piston has a reduced diameter portion which provides a primary piston. A piston annulus is slidably mounted thereon and provides a secondary piston. An annular actuation chamber adjoins the secondary piston opposite the pressurization chamber. An actuation passage is provided between a return fuel drain and the actuation chamber, which is selectively open or closed passively by pump piston movement and/or dynamically by operation of an actuation solenoid valve. If the actuation chamber passage is open, then during the pressurization stroke the secondary piston will remain stationary relative to the pump body, but if it is closed then the secondary piston must stroke in unison with the primary piston.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.