Abstract: A nozzle body has an injection hole configured to inject fuel and a fuel passage connecting to the injection hole. A needle is configured to open and close the fuel passage to switch between fuel injection from the injection hole and stop of the fuel injection. An injection hole axis is an imaginary line extending along a center of the injection hole. An injection hole perpendicular cross section is a cross section of the injection hole perpendicular to the injection hole axis. The injection hole perpendicular cross section has a flat shape. The injection hole perpendicular cross section has an area that gradually expands from an inlet of the injection hole to an outlet of the injection hole while maintaining a similar shape.

Abstract: At least one of nozzle holes is provided as a non-circular nozzle hole where the ratio of the longest diameter to the shortest diameter of an outlet opening portion is greater than 1. A virtual non-circular cone and a virtual circular cone are defined for each of the non-circular nozzle hole and a circular nozzle hole where the ratio of the longest diameter to the shortest diameter of the outlet opening portion is 1. At least two adjacent nozzle holes are formed such that the virtual non-circular cone does not interfere with the virtual circular cone or the virtual non-circular cone.

Abstract: A nozzle body has an injection hole configured to inject fuel and a fuel passage connecting to the injection hole. A needle is configured to open and close the fuel passage to switch between fuel injection from the injection hole and stop of the fuel injection. An injection hole axis is an imaginary line extending along a center of the injection hole. An injection hole perpendicular cross section is a cross section of the injection hole perpendicular to the injection hole axis. The injection hole perpendicular cross section has a flat shape. The injection hole perpendicular cross section has an area that gradually expands from an inlet of the injection hole to an outlet of the injection hole while maintaining a similar shape.

Abstract: A needle includes a first seal portion, which is formed at an end portion of the needle located on a side where an injection hole is placed, and a second seal portion, which is formed on a side of the first seal portion where a stationary core is placed. When a boundary between a first outer wall of the first seal portion and a second outer wall of the second seal portion is lifted away from or is seated against an inner wall, the injection hole is opened or closed. Thereby, a seat diameter of the boundary and the inner wall is stabilized, and a change in a fuel injection quantity caused by aging can be reduced. Furthermore, the first outer wall of the first seal portion is shaped into a form of a spherical surface.

Abstract: In a fuel injector 10, a first injection hole 155a and a second injection hole 155b having reference inside diameters Dn1, Dn2 different from each other are formed as a plurality of injection holes 155. In such a configuration, an L/D value obtained by dividing the flow channel length Ln1 of the first injection hole 155a by the reference inside diameter Dn1 of the first injection hole 155a agrees to an L/D value obtained by dividing the flow channel length Ln2 of the second injection hole 155b by the reference inside diameter Dn2 of the second injection hole 155b.

Abstract: In a fuel injector 10, a first injection hole 155a and a second injection hole 155b having reference inside diameters Dn1, Dn2 different from each other are formed as a plurality of injection holes 155. In such a configuration, an L/D value obtained by dividing the flow channel length Ln1 of the first injection hole 155a by the reference inside diameter Dn1 of the first injection hole 155a agrees to an L/D value obtained by dividing the flow channel length Ln2 of the second injection hole 155b by the reference inside diameter Dn2 of the second injection hole 155b.

Abstract: In a fuel injection valve, a first injection hole and a second injection hole having reference inside diameters Dn1, Dn2 different from each other are formed as a plurality of injection holes. In such a configuration, an L/D value obtained by dividing the flow channel length Ln1 of the first injection hole by the reference inside diameter Dn1 of the first injection hole agrees to an L/D value obtained by dividing the flow channel length Ln2 of the second injection hole by the reference inside diameter Dn2 of the second injection hole.

Abstract: A needle includes a first seal portion, which is formed at an end portion of the needle located on a side where an injection hole is placed, and a second seal portion, which is formed on a side of the first seal portion where a stationary core is placed. When a boundary between a first outer wall of the first seal portion and a second outer wall of the second seal portion is lifted away from or is seated against an inner wall, the injection hole is opened or closed. Thereby, a seat diameter of the boundary and the inner wall is stabilized, and a change in a fuel injection quantity caused by aging can be reduced. Furthermore, the first outer wall of the first seal portion is shaped into a form of a spherical surface.

Abstract: In a fuel injection valve, a first injection hole and a second injection hole having reference inside diameters Dn1, Dn2 different from each other are formed as a plurality of injection holes. In such a configuration, an L/D value obtained by dividing the flow channel length Ln1 of the first injection hole by the reference inside diameter Dn1 of the first injection hole agrees to an L/D value obtained by dividing the flow channel length Ln2 of the second injection hole by the reference inside diameter Dn2 of the second injection hole.

Abstract: A fuel injector has a valve nozzle defining a fuel-injection port downstream of a fuel passage. The fuel-injection port is inclined toward a nozzle periphery from a fuel-inlet to a fuel-outlet. A valve needle is capable of moving in a valve-opening direction to open the fuel-injection port so that a fuel flowing into the fuel-inlet from the nozzle periphery is injected into an internal combustion engine. The fuel-injection port has an upstream-portion defining the fuel-inlet, and a downstream-portion defining the fuel-outlet. The downstream-portion is smoothly connected to the upstream-portion at a position most close to a center of the valve nozzle, and the downstream-portion is offset toward the nozzle periphery relative to the upstream-portion, so that the upstream-portion and the downstream-portion forms a step surface therebetween. The step surface is eccentric to a center line of the upstream-portion.

Abstract: A fuel injector has a valve nozzle defining a fuel-injection port downstream of a fuel passage. The fuel-injection port is inclined toward a nozzle periphery from a fuel-inlet to a fuel-outlet. A valve needle is capable of moving in a valve-opening direction to open the fuel-injection port so that a fuel flowing into the fuel-inlet from the nozzle periphery is injected into an internal combustion engine. The fuel-injection port has an upstream-portion defining the fuel-inlet, and a downstream-portion defining the fuel-outlet. The downstream-portion is smoothly connected to the upstream-portion at a position most close to a center of the valve nozzle, and the downstream-portion is offset toward the nozzle periphery relative to the upstream-portion, so that the upstream-portion and the downstream-portion forms a step surface therebetween. The step surface is eccentric to a center line of the upstream-portion.