Patent ID: 6439482
Filing Date: 2002-08-27
Classification: F02M

Abstract:
A fuel injection system comprising a cylindrical fuel swirler having plural swirl grooves, a valve seat engaged with a swirl groove-carrying surface of the fuel swirler and having a fuel injection port, an annular fuel swirl chamber formed between the fuel swirler and valve seat and communicating with the swirl grooves and fuel injection port, and a valve body adapted to be moved forward and backward in a cylindrical hole of the fuel swirler in the axial direction thereof and thereby engaged with and disengaged from the valve seat to cause a communication passage between the fuel swirl chamber and fuel injection port to be closed and opened, whereina minimum cross-sectional area S1 of a clearance between the valve body and valve seat with the communication port fully opened being smaller than an area S2 of the cross section of the fuel injection port which is perpendicular to the axis thereof, and larger than an average area S3 of the cross section of the fuel injection port which is perpendicular to the direction in which a fuel flow advances.