Among all combinations of two injection holes, in a combination in which when the injection holes are offset such that their central axes are coincident with each other in inlet openings, an inter-injection hole angle formed by the central axes is minimized, the inter-injection hole angle between the two injection holes is represented as yamin[deg], taper angles, which are formed by the respective contours of the injection hole inner walls in the cross sections along the virtual planes including the central axes of the two injection holes that allow the inter-injection hole angle to be minimized, are represented as a1 and a2[deg], and when fuel is injected from the injection holes, average pressure of the fuel in the fuel passage is represented as P[Mpa], and the injection holes are formed so as to satisfy a relationship: amina1+a2+0.5P.sup.0.6.

An injection hole has an injection hole passage communicating an inner opening with an outer opening. The inner opening is smaller than the outer opening in cross-sectional area. The needle moves in a valve closing direction to abut against a valve seat to restrict a flow of fuel through the injection hole. A first inner wall of the injection hole is located on a valve closing direction side relative to an injection hole axis. A second inner wall of the injection hole is located on an opposite side of the injection hole axis from the valve closing direction side. The injection hole passage is defined by the first inner wall and the second inner wall.

Methods and systems are provided for a fuel injector. In one example, a system may include a fuel injector having a half-annular venturi shaped outlet passage arranged between an outlet surface of the fuel injector and a half-cone shaped end portion of a nozzle. The nozzle may further comprise one or more air entraining features working in tandem with the half-annular venturi outlet passage to promote air-fuel mixing.

Methods and systems are provided for an injector. In one example, the injector comprises at least two passages, wherein outlets of each of the passages are differently shaped than corresponding inlets of the passages. Further, in one or more examples, each of the outlets may be shaped and sized differently with respect to each other.

Methods and systems are provided for a fuel injector. In one example, a system comprises an injector spool valve having a fuel outlet shaped to flow fuel to different portions of a nozzle inlet based on an actuation of the injector spool valve, thereby adjusting a fuel injection angle of a fuel injection.

In an injection hole set, primary and secondary injection holes are formed to satisfy the following relationship: t1+t20.87P{circumflex over ()}0.52, where (deg) is an injection-hole-to-injection-hole angle, which is an angle formed between a primary central axis of the primary injection hole and a secondary central axis of the secondary injection hole; t1 (deg) is a primary taper angle, which is an angle formed between outlines of a primary injection hole inner wall of the primary injection hole in a cross section of the primary injection hole inner wall; t2 (deg) is a secondary taper angle, which is an angle formed between outlines of a secondary injection hole inner wall of the secondary injection hole in a cross section of the secondary injection hole inner wall; and P (MPa) is an average pressure of the fuel in a fuel passage at a time of injecting the fuel from the injection holes.

A throttle body fuel injection system including a throttle body with at least one air intake, a fuel injector coupled to the throttle body at a fuel port and an annular ring coupled to the cylindrical inner wall of the air intake. The annular ring includes a primary fuel discharge orifice adjacent to the fuel port and a plurality of secondary fuel discharge orifices arranged radially around the annular ring for spraying atomized fuel into the air intake.

A nozzle hole of a nozzle plate is coupled to a fuel injection port of a fuel injection device via a swirl chamber and first and second fuel guide channels opened into the swirl chamber. The swirl chamber is formed by combining first and second elliptical-shaped recessed portions. The first fuel guide channel opens at a side of a short axis of the first elliptical-shaped recessed portion and a side of the short axis that does not overlap with the second elliptical-shaped recessed portion, and the second fuel guide channel opens at a side of a short axis of the second elliptical-shaped recessed portion and a side of the short axis that does not overlap with the first elliptical-shaped recessed portion. The first and second fuel guide channels have depths deeper than those of the swirl chamber and extend inside of the swirl chamber while gradually reducing cross-sectional areas.

A fuel injector for an internal combustion engine is disclosed. The fuel injector includes a body defining an orifice. The orifice is configured to provide passage to a fuel into a combustion chamber of the internal combustion engine. The orifice includes an inlet port having a first oval shape and an outlet port having a second oval shape. The second al shape is orthogonal to the first oval shape. Moreover, a transition from the first oval shape to the second oval shape defines a stagnation plane, facilitating an exit of the fuel as a fan spray from the outlet port.

Methods and systems are provided for an injector. In one example, the injector comprises at least two passages, wherein outlets of each of the passages are differently shaped than corresponding inlets of the passages.