Accumulator fuel injection system
US5341783A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Sep 3, 1993 |
| Grant date | Aug 30, 1994 |
| Priority date | — |
| Expiry date | Sep 3, 2013 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M2200/30
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A series of method and apparatus advances in the accumulator-type fuel injector art, applicable to both intensified and unintensified accumulator injectors, which cooperate to provide major improvements in internal combustion engine fuel economy, reduction of noise, and reduction of undesirable exhaust emissions, including smoke, oxides of nitrogen and hydrocarbons. According to the invention, injector needle closure speed is increased for sharper fuel cutoff and better atomization proximate closure, and needle closure bounce is minimized to minimize fuel dribble proximate closure by reducing both mass and length of the needle, which can be accomplished by a longitudinally divided needle. Hydraulic damping also damps and cushions both needle closing and needle opening. The accumulator cavity and needle spring cavity are separated, enabling the accumulator cavity to be as small as desired for high accumulator closing pressure, while nevertheless enabling a strong, fast-acting spring to be used, both factors cumulatively contributing to good closure atomization. A two-stage needle lift is provided for first injecting a pilot fuel charge for preignition, and then injecting the main fu…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.