An injection hole body has an injection hole to inject fuel for causing combustion in an internal combustion engine. A valve body is unseated from and seated on a seating surface of the injection hole body. The injection hole body and the valve body form a fuel passage therebetween to communicate with an inflow port of the injection hole. The fuel passage is opened and closed by unseating and seating of the valve body. A resilient member generates a resilient force to urge the valve body toward the seating surface. A seat angle is an angle between two straight lines appearing in a cross section of the seating surface, the cross section including a center axis of the valve body. The seat angle is 90 degrees or less.

A method of fabricating a nozzle that includes casting and curing a first material using a patterned nip roller to form a first microstructured pattern of discrete microstructures, deforming at least one of the discrete microstructures; replicating the first microstructured pattern, including the at least one deformed discrete microstructure, in a second material different than the first material to make a replicated structure comprising a plurality of blind holes formed in the second material, removing second material of the replicated structure to expose tops of microstructures in the first microstructured pattern, and removing the first material from the replicated structure, resulting in a nozzle having a plurality of through-holes in the second material and corresponding to the first microstructured pattern.

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 a min[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: a mina1+a2+0.5P.sup.0.6.

A fuel injection valve according to the present invention has an expanded portion formed in a first injection-hole plate on an upstream side, thereby allowing positional misalignment between injection-hole portions. As a result, a radial dimension between an inner diameter-side circumferential edge of an upstream-side injection hole outlet portion and an inner diameter-side circumferential edge of a downstream-side injection hole inlet portion is not required. Thus, a plate thickness of a second injection-hole plate on a downstream side can be kept to minimum. As a result, weldability between an injection-hole plate body and a valve seat is improved.

An engine head assembly includes a plurality of fuel injectors each positioned within a fuel injector bore in an engine head, and fluidly coupled with a fluid conduit. Each fuel injector includes a valve assembly within a fuel injector case such that an interior fluid space is formed between the fuel injector case and the valve assembly. The fuel injector case includes an elongate body having a particulate-blocking perforation array formed therein, and that is structured to block particulates in fuel entering the fuel injector from the fluid conduit.

A throttle portion is defined between an upper end of a sac chamber and a conical portion of a needle to have a throttle opening area S1. Half of an area surrounded by the throttle portion, the needle, an inner wall of the sac chamber, and a lower end extended line in a cross section of the sac chamber taken along a sac center line is an injection hole upstream area S2. A lift amount, when the throttle opening area S1 is equal to an area which is calculated by multiplying an injection hole area S3 by the number of the injection holes, is a predetermined lift amount L. A viscosity coefficient of fuel is . An index value Sa, which is calculated in accordance with an equation as below, is set to 0.5 or greater. $S_a=\frac{}{2}{}_{h=0}^{h=L}{\left(\frac{S_1}{S_2-S_1}\right)}^2\mathrm{dh}$

A fuel and gas mixing structure for an engine is provided. This mixing structure includes a body configured to be positioned between a fuel injector and a cylinder of an engine. The body defines an interior volume that is configured to receive gas from outside the body and to receive one or more streams of fuel from the fuel injector in the interior volume. The body also defines one or more mixture conduits configured to conduct plumes of the fuel and gas, while mixing, from the interior volume to one or more exit ports and therethrough to the cylinder.

Provided is a structure capable of reducing dribbling of fuel generated when a valve body is closed. In order to achieve the above object, a fuel injection device includes: a valve body; and a seat member having a seat portion on which the valve body is seated and having a fuel injection hole formed on a downstream side of the seat portion. The seat member is formed such that a gap between the seat member and the opposing valve body in the whole region on the downstream side of the fuel injection hole is smaller than a diameter of the fuel injection hole.

An engine head assembly includes a plurality of fuel injectors each positioned within a fuel injector bore in an engine head, and fluidly coupled with a fluid conduit. Each fuel injector includes a valve assembly within a fuel injector case such that an interior fluid space is formed between the fuel injector case and the valve assembly. The fuel injector case includes an elongate body having a particulate-blocking perforation array formed therein, and that is structured to block particulates in fuel entering the fuel injector from the fluid conduit.

A fuel injector and method are disclosed including an injector body with a fuel sac, and an end positioned into a combustion chamber. A main fuel passage, having a varying cross-sectional area forming a reduced pressure region, fluidically couples the fuel sac to the combustion chamber. One or more additional passages fluidically couple the reduced pressure region with one or both of the fuel sac and the combustion chamber.