Fuel injector with spiral-wound spring adjustment tube
US6644568B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Oct 24, 2002 |
| Grant date | Nov 11, 2003 |
| Priority date | — |
| Expiry date | Oct 24, 2022 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M2200/505
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
A top-feed electronic fuel injector for an internal combustion engine includes an injector body having a valve seat disposed opposite a generally cylindrical bore of nominal inner diameter defined within the injector body. A needle valve moves within the passage between a closed position against the valve seat, as urged by a coil spring disposed within the bore, and an open position away from the valve seat. The coil spring is seated against an end face a spring adjustment tube that is pressed into the bore. The spring adjustment tube, which is formed of rolled sheet stock to provide a “spiral-wound” configuration featuring at least 1.5 turns, end-to-end, when the spring adjustment tube is viewed in a transverse section, resiliently presses against the walls of the bore to maintain its position and, hence, calibrate the spring force applied to the needle valve.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.