Fuel injector nozzle assembly with improved needle check valve stop mechanism
US6062497A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Jan 19, 1996 |
| Grant date | May 16, 2000 |
| Priority date | — |
| Expiry date | Jan 19, 2016 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF02M2200/04
- WIPO fieldEngines, pumps, turbines
- WIPO sectorMechanical engineering
Abstract
In some fuel injectors having VOP (valve opening pressure) type needle checks, the check return spring cavity also functions as a portion of the fuel supply passage. A return spring is compressed within the return spring cavity between an end wall and one end of the needle check. Instead of utilizing a pin stop to limit the movement of the needle check as in the prior art, the present invention utilizes a shoulder stop surface which comes into contact with one end of the needle check when the needle valve is fully open. This elimination of the prior art pin stop is believed to eliminate or reduce cavitation damage to the check return spring, pin chipping problems, beat in problems due to pin stop cocking or tipping within the return spring cavity, and other wear and functionality problems caused by a free floating pin stop.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.