Patent ID: 9732716
Date: 2017-08-15
CPC Classifications: F02M

Claim:
1. A fuel injection nozzle comprising: a nozzle body that is shaped into a tubular form; and a needle that is received in an inside of the nozzle body in such a manner that the needle is movable in an axial direction of the nozzle body, wherein the fuel injection nozzle starts or stops injection of fuel by lifting or seating the needle relative to a seat portion, which is formed in an inner peripheral portion of the nozzle body, wherein: the nozzle body includes an injection hole that opens in both of an inner wall and an outer wall of the nozzle body on a tip end side of the seat portion in the axial direction, wherein the tip end side is a side where a tip end of the nozzle body is placed, while a rear end side is a side where a rear end of the nozzle body is placed; in a state where the needle is seated against the seat portion, when the needle is moved from the seat portion toward the rear end side in the axial direction, the needle is lifted from the seat portion, and thereby the fuel is guided from the inside of the nozzle body to an outside of the nozzle body through the injection hole; with respect to an inlet, which is an opening of the injection hole in the inner wall, an inlet transverse axis is defined to extend in a circumferential direction of the nozzle body in parallel with a plane of the inlet, and an inlet longitudinal axis is defined to extend in a direction perpendicular to the inlet transverse axis in parallel with the plane of the inlet; with respect to an outlet, which is an opening of the injection hole in the outer wall, an outlet transverse axis is defined to extend in the circumferential direction in parallel with a plane of the outlet, and an outlet longitudinal axis is defined to extend in a direction perpendicular to the outlet transverse axis in parallel with the plane of the outlet; a maximum value of a longitudinal length of the inlet measured in a direction of the inlet longitudinal axis is larger than a maximum value of a longitudinal length of the outlet measured in a direction of the outlet longitudinal axis; a maximum value of a transverse length of the inlet measured in the direction of the inlet transverse axis is defined between two maximum transverse length forming points of an opening edge of the inlet, and a rear end portion of the opening edge of the inlet, which is located on the rear end side of the two maximum transverse length forming points, is shaped into an arc; a remaining portion of the opening edge of the inlet, which is other than the rear end portion and is located on the tip end side of the two maximum transverse length forming points, includes two straight lateral edges, which extend linearly and are respectively placed at one circumferential side and another circumferential side of the opening edge of the inlet; and the two straight lateral edges are tapered toward the tip end side, and thereby the transverse length, which is measured between the two straight lateral edges in the direction of the inlet transverse axis, is progressively decreased from the two maximum transverse length forming points toward a tip end of the opening edge of the inlet.