Patent ID: 7086615

Claim:
A fuel injector for metering, atomizing and spray targeting of fuel, the fuel injector comprising: a seat including a passage extending along a longitudinal axis; a movable member cooperating with the seat to permit and prevent a flow of fuel through the passage; and an orifice disc including: a member including first and second generally parallel surfaces, the first surface generally confronting the seat, and the second surface facing opposite the first surface; and an orifice extending through the member between first and second generally planar surfaces of the member along an orifice axis and being defined by a wall coupling the first and second surfaces, the wall including: a first wall portion spaced from the first surface, the first wall portion extending substantially perpendicular to the first and second generally planar surfaces and about the longitudinal axis to define a transition perimeter; and a second wall portion coupling the first wall portion to the first surface to define a inlet perimeter on the first surface, the inlet perimeter including: a plurality of curved surfaces connecting the inlet perimeter and the transition perimeter, each of the plurality of curved surfaces being separated by adjacent curved surfaces by a line connecting the inlet and transition perimeters in a helical orientation with respect to the orifice axis.