Variable orifice fuel injection nozzle
View Patent ↗The present device involves a fuel injector nozzle and control system for delivering a fine atomized fuel that is evenly mixed throughout the compressed air charge across a wide range of throttle positions. The system includes a pintle rod that is incrementally moveable to release a high pressure atomized stream of fuel through one or more apertures to vary the size of the opening through which the fuel is directed into the compressed air charge. The atomized fuel is delivered in a manner that allows the fine particles of fuel to be evenly distributed throughout the compressed air charge for more complete and consistent combustion.
1 . A self-cleaning fuel injector nozzle for a fuel injector comprising:
a nozzle body coupled to an end portion of the fuel injector, said nozzle body having at least one channel for receiving liquid fuel therein said nozzle body having an inner bore, wherein the nozzle body has a plurality of nozzle orifices extending from an inner surface to an outer surface of the nozzle body;
a pintle rod slidably disposed within said inner bore of said nozzle body wherein said pintle rod is slip fit within said inner bore of said nozzle body; and
a spring coupled to said pintle rod, said spring configured to provide a closing force to the pintle rod to selectively move the pintle rod to prevent fuel flow;
wherein said pintle rod is configured to move within said inner bore flush against said plurality of nozzle orifices, and entirely across an inner entrance of said plurality of nozzle orifices allowing fuel to pass when said plurality of nozzle orifices are open, stopping fuel flow when said plurality of nozzle orifices are closed, and dislodging any blockage in at least one of the plurality of nozzle orifices when said pintle rod is closing at least one of said plurality of nozzle orifices;
wherein said pintle rod has an undercut positioned behind a forward end of the pintle rod, and the undercut provides a spool surface for operation of the pintle rod in response to fuel pressure;
wherein the spool surface includes a corner having a point, said point configured to chop up said blockage in at least one of said plurality of nozzle orifices and dislodge said blockage in at least one of the plurality of nozzle orifices.
2 . The self-cleaning fuel injector nozzle as in claim 1 , wherein said pintle rod has a cutter for chopping up said blockage in at least one of said plurality of nozzle orifices to dislodge said blockage in at least one of said plurality of nozzle orifices.
3 . The self-cleaning fuel injector nozzle as in The self-cleaning fuel injector nozzle as in wherein said nozzle body has an orifice body positioned along a longitudinal axis of the nozzle body, wherein said plurality of nozzle orifices are disposed in said orifice body, and wherein said pintle rod having the forward end which is constructed as a cylinder to slip fit within the inner bore of the orifice body, wherein said pintle rod has the undercut positioned behind the forward end to provide for fuel flow between an outer diameter of the pintle rod and the inner bore of the undercut, and wherein the nozzle further comprises a plunger coupled to said spring.
4 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the orifice body has multiple levels of varying diameter holes arranged in a radial pattern around the perimeter of the orifice body.
5 . The self-cleaning fuel injector nozzle as in claim 3 , wherein the nozzle is a direct replacement for a conventional fuel injector nozzle employing a return spring setup.
6 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the orifice body is made of Tungsten carbide or ceramic to provide long life and wear resistant.
7 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the pintle rod is made of Tungsten carbide or ceramic to provide long life and wear resistant.
8 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein said pintle rod moves back and forth in a repeating manner to repeatedly chop and dislodge said blockage while said blockage is positioned adjacent to at least one of said plurality of nozzle orifices.
9 . The self-cleaning fuel injector nozzle for a fuel injector as in claim 1 , wherein the pintle rod is configured such that wherein as the dislodging continues, a size of the blockage reduces until the blockage passes through at least one of the plurality of nozzle offices.
10 . The self cleaning fuel injector nozzle for a fuel injector as in claim 1 , wherein said blockage is in a form of a particle disposed in fuel, wherein said pintle rod has an edge that serves as a cutter, wherein said pintle rod is configured to repeatedly move back and forth inside said inner bore via said spring to chop said particle until it enters an opening of at least one of said nozzle orifices.
11 . The self cleaning fuel injector nozzle for a fuel injector as in claim 1 , wherein at least one of said nozzle orifices of said plurality of nozzle orifices varies in cross sectional area from an inside face of said at least one nozzle orifice to an outside face of said at least one nozzle orifice.
12 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , including a pintle flange to limit forward movement to the pintle rod.
13 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the spool surface includes said corner having the point.
14 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the pintle rod includes a rear stop to limit travel of the pintle rod in a direction to prevent a flow of fuel through the nozzle when no external forces are present to move the radial flow pintle rod to an open position.
15 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the plurality of nozzle orifices are all opened simultaneously with linear movement of the pintle rod.
16 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the nozzle orifices are all opened sequentially with linear movement of the pintle rod.
17 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the nozzle orifices are positioned in two or more radial levels so that the nozzle orifices are positioned in two or more radial levels so that the nozzle orifices are opened sequentially with linear movement of the pintle rod.
18 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the nozzle orifices are all opened simultaneously with linear movement of the pintle rod.
19 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the nozzle orifices are less than 0.006 inches or 0.15 mm.
20 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the nozzle orifices have a diameter that is 0.058 millimeters or less.
21 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the nozzle orifices a keyhole orifice.
22 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , including a servo-controlled metering valve for controlling the flow and pressure of fuel provided to the nozzle body.
23 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 22 , wherein the servo-controlled metering valve provides the fuel flow at a predetermined pressure regardless of the fuel volume.
24 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 23 , wherein the servo-controlled metering valve includes a metering rod, the metering rod constructed and arranged to slide in a metering rod bore positioned within a metering block.
25 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 24 , wherein the servo includes a metering cam having an offset journal, the offset journal positioned to cooperate with a distal end of the metering rod to control the movement of the metering rod within the metering rod bore.
26 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the pintle rod is tubular, a distal end of the inner bore is blocked with an end plug to prevent fuel from flowing straight out the front of the surface of the inner bore.
27 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 3 , wherein the orifice body includes fuel notches arranged in a radial pattern around a perimeter of the orifice body.
28 . The self-cleaning fuel injector nozzle for a fuel injector as claimed in claim 27 , wherein the fuel notches have a root width approaching a point expanding as the notch progresses to the end plug of the orifice body.