| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a fuel injector which enables the high atomization of a fuel spray. <P>SOLUTION: A valve body 30 includes a valve seat 31 of a taper form, a recess 34 axially recessed at the downstream side of the valve seat 31, and a plurality of nozzle holes 32 penetrating from the inner wall to the outer wall of the recess 34 positioned on the virtual surface C where the valve seat 31 is extended at the recess side. A needle valve 40 includes a valve seat 41 to sit on or to be separated from the valve seat 31 and a tip 42 projecting to the recess 34 side at the downstream side of the valve seat 41. The outer diameter Ds of the valve seat 41, a distance A between a nozzle hole inlet port and the tip 42, a distance B between the inner wall of the recess 34 on the center axis side rather than each of the nozzle holes 32 and the tip 42, and a relation between the inner diameter d1 of the nozzle hole inlet port side and the inner diameter d2 of a nozzle hole outlet port side are 0.048≤A/Ds≤0.18, B/Ds≤0.18, d2>d1. Thus, the fuel injection device can make the fuel injected from the nozzle holes 32 into a thin fuel film while maintaining the kinetic energy of the fuel. <P>COPYRIGHT: (C)2013,JPO&INPIT</p> |
