Claims
- 1. A fuel injector comprising:a housing having passageway extending between an inlet and an outlet along a longitudinal axis; a seat having a sealing surface facing the inlet, a first channel surface facing the outlet, and a seat orifice disposed between the sealing surface and the first channel surface; a closure member disposed in the passageway and contiguous to the sealing surface so as to generally preclude fuel flow through the seat orifice, the closure member being coupled to a magnetic actuator that, when energized, positions the closure member away from the sealing surface of the seat so as to allow fuel flow through the passageway and past the closure member; a metering disc proximate the first channel surface so that a virtual extension of the sealing surface onto the metering disc defines a first virtual circle about the longitudinal axis prior to an intersection of the virtual extension with the longitudinal axis, the metering disc including a second channel surface confronting the first channel surface, the metering disc having a plurality of metering orifices, each of the metering orifices having generally parallel surfaces extending through the metering disc generally parallel to the longitudinal axis, the metering disc including a solid imperforate portion within the first virtual circle and all of the metering orifices being located about the longitudinal axis outside the first virtual circle; and a controlled velocity channel being defined by the first and second channel surfaces, the controlled velocity channel having a first portion changing in cross-sectional area as the channel extends outwardly from the orifice of the seat to the plurality of metering orifices, wherein the channel extends between a first end and a second end, the first end disposed at a first radius from the longitudinal axis with the first and second channel surfaces spaced apart along the longitudinal axis at a first distance, the second end disposed at a second radius proximate the plurality of metering openings with respect to the longitudinal axis with the first and second channel surfaces spaced apart along the longitudinal axis at a second distance such that a product of two times the trigonometric constant pi (π) times the first radius and the first distance is different than a product of two times the trigonometric constant pi (π) of the second radius and the second distance so that a velocity of fuel flow through the channel varies from the seat orifice to the plurality of metering orifices.
- 2. The fuel injector of claim 1, wherein the plurality of metering orifices comprises at least two metering orifices diametrically disposed outside the first virtual circle.
- 3. The fuel injector of claim 1, wherein the at least two metering orifices comprises eight metering orifices diametrically disposed outside the first virtual circle about the longitudinal axis.
- 4. The fuel injector of claim 2, wherein the plurality of metering orifices comprises at least two metering orifices disposed at a first arcuate distance relative to each other proximate a second virtual circle generally concentric about the longitudinal axis.
- 5. The fuel injector of claim 2, wherein the plurality of metering orifices comprises at least three metering orifices spaced at different arcuate distances proximate a second virtual circle generally concentric about the longitudinal axis.
- 6. The fuel injector of claim 1, wherein the controlled velocity channel comprises a second portion having a constant cross-sectional area.
- 7. The fuel injector of claim 1, wherein the channel is configured so that fuel flow accelerates through the channel.
- 8. The fuel injector of claim 7, wherein the channel comprises a first channel end adjacent the seat orifice with the first and second channel surfaces of the first channel end being spaced apart at approximately a first distance along the longitudinal axis and a second channel end adjacent a metering orifice with the first and second channel surfaces of the second channel end being spaced apart at approximately a second distance along the longitudinal axis, the second distance being less than the first distance, so that a velocity of fuel proximate the metering orifices is greater than the velocity of fuel proximate the seat orifice as fuel flow from the seat orifice through the channel to the metering orifices.
Parent Case Info
The present application is a continuation application filed pursuant to 35 U.S.C. §§120 and 121 and claims the benefits of prior application Ser. No. 09/568,464, filed on May 10, 2000, pending, which is hereby incorporated by reference in its entirety.
US Referenced Citations (18)
Foreign Referenced Citations (2)
Number |
Date |
Country |
1 092 865 |
Apr 2001 |
EP |
2000-097129 |
Sep 2000 |
JP |
Continuations (1)
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Number |
Date |
Country |
Parent |
09/568464 |
May 2000 |
US |
Child |
10/247351 |
|
US |