| 摘要 |
PROBLEM TO BE SOLVED: To provide a fuel injection valve having improved spray characteristics.SOLUTION: A fuel injection valve comprises: a needle 2 including a valve body portion 17 provided in a tip end portion thereof; and a nozzle body 1 accommodating therein the needle 2 so as to be able to move the needle 2 up and down, and including a seat portion 5, the valve body portion 17 being able to abut on a tip end portion of the seat portion 5, and controls fuel injection in response to lift of the needle 2, a sack chamber 13 being provided in an extreme tip end portion of the nozzle body 1, the sack chamber 13 being constituted by a hemispherical portion 13a including a hemispherical inner surface and a tubular portion 13b whose one end is connected to the seat portion 5 and whose other end is connected to the hemispherical portion 13a, an injection hole 4 communicating with the hemispherical portion 13a being provided in the nozzle body 1, and a portion 17b formed on a tip end of the valve body portion 17 and formed into a truncated conical shape converging toward a tip end direction being provided in the needle 2. A diameter Dof one end of the tubular portion is set equal to or smaller than 0.8 mm, and a distance h between a truncated surface 9 of the portion 17b and an extreme tip end portion 10 of the hemispherical portion 13a at a time of abutment between the valve body portion 17 and the seat portion 5 is set to be equal to or smaller than 0.15 mm. |
