It is prevented that residual fuel left in the vicinity of an injection nozzle outlet is carbonized to cause adherence of the carbonized fuel as deposit and changing of a spray pattern or an injection flow rate. A fuel injection valve includes a seat portion on which a valve body is seated and a seat portion in which an injection hole for injecting fuel downstream from the seat portion is formed, in which a concave surface denting in a direction opposite to a fuel injecting direction is formed on an outer peripheral side away from the injection hole at an end face located downstream of the seat member, and the concave surface is formed such that a material surface in an outer peripheral region has a larger wettability for the fuel than in an inner peripheral region.

A spark-ignition direct fuel injection valve includes, at least, a seat member provided with a fuel injection hole and a valve seat and a valve body which controls fuel injection from the injection hole by contacting and separating from the valve seat. In the spark-ignition direct fuel injection valve: the injection hole has an injection hole inlet which is open inwardly of the seat member and an injection hole outlet which is open outwardly of the seat member; an opening edge of the injection hole inlet has a first round-chamfered portion formed on an upstream side with respect to a fuel flow toward the injection hole inlet; and an extending length (L) of the injection hole does not exceed three times a hole diameter (D) of the injection hole.

An object of the invention is to provide a drive device of a fuel injection device which can increase the accuracy in an injected fuel injection amount by combining the fuel injections from a plurality of injection pulse widths. In the drive device of the fuel injection device which has a function of driving the fuel injection device such that the fuel injection is performed plural times in one combustion cycle, the fuel injection device is driven such that a fuel injection at a target opening level in which a valve element or a movable element of the fuel injection device reaches a regulation member and a fuel injection at an intermediate opening level in which the valve element does not reach the regulation member are included in the plural times of division injections performed in one combustion cycle.

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.

Fuel flows from first and second fuel guide channels into the swirl chamber and is guided to the nozzle hole while swirling in the swirl chamber in the identical direction. The nozzle hole is divided into an inlet portion near a fuel-inflow end and an outlet portion near a fuel-outflow end. The outlet portion has a flow passage cross-sectional area gradually increasing towards a fuel outflow-side opening end, and includes a curved surface formed by smoothly connecting an inner surface of the nozzle holes at an upstream end side in a fuel flow direction to an inner surface of the nozzle holes at the portion near the fuel-inflow end so as to smoothly and gradually increase the flow passage cross-sectional area. The curved surface ensures further thin film-like flow by expanding a flow of the fuel in the nozzle holes by the Coanda effect.

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.

A needle has a seal portion that contacts a valve seat, and is provided so as to be able to reciprocate inside a valve body. A sack chamber is formed between the seal portion and a recess. A seal portion is formed in a curved shape protruding in the axial direction of the needle. A distance between an inlet intersection and a needle intersection on a same virtual straight line is defined as a distance Dh, and a distance between the recess and the seal portion on an axis of the valve body is defined as a distance Ds. When the seal portion is in contact with the valve seat, the distance Dh is larger than the distance Ds (Dh>Ds).

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.

Nozzles and method of making the same are disclosed. The disclosed nozzles have at least one nozzle through-hole therein, wherein the at least one nozzle through-hole exhibits a coefficient of discharge, C.sub.D, of greater than about 0.50. Fuel injectors containing the nozzle are also disclosed. Methods of making and using nozzles and fuel injectors are further disclosed.