| 摘要 |
PROBLEM TO BE SOLVED: To provide a fuel injection nozzle 1 capable of preventing leak of fuel from a second injection hole 8 at a time of low lift of a needle 3 and reducing dead volume in a suck chamber 9. SOLUTION: A projection end part 14 entering the suck chamber 9 of a nozzle body 2 is provided on a tip part of the needle 3, and a recess groove 14a is formed on an outer circumference surface of the projection end part 14. A valve member 4 is provided in a space formed between an inner circumference surface of the suck chamber 9 and the recess groove 14a, and is arranged close to an inlet of the second injection hole 8. Negative pressure is generated when fuel of high speed passes through a narrow gap between the valve element 4 and the second injection hole 8 at a time of low lift of the needle 3 and the negative pressure acts as force pulling the valve member 4 to the inlet of the second injection hole 8. Consequently, since the valve member 4 is pressed against the inlet of the second injection hole by pressure difference acting on the valve member 4 when the valve element 4 closes the inlet of the second injection hole 8, the inlet of the valve member 4 of the second injection hole 8 is surely closed by the valve member 4. COPYRIGHT: (C)2006,JPO&NCIPI
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