| 摘要 |
PURPOSE:To increase the pressure at the injection end than that at the injection start, decrease noises, and reduce the smoke occurrence by restricting the shift quantity of a needly valve via the pressure of a damper chamber. CONSTITUTION:When a needle valve 18 and a damper plunger 25 continue their lift in one body and the spindle 33 of the damper plunger 25 opens a spill port 34, the fuel in an accumulator chamber 13 flows into a damper chamber 24. Thereby, the fuel pressure in the accumulator chamber 13 is decreased and the pressure in the damper chamber 24 is increased. As a result, the pressure in a nozzle chamber 16 and the pressure in the damper chamber 24 arr balanced, and the needle valve 18 is abruptly pushed down by the force of a spring 23 to close an injection nozzle 17. Accordingly, such characteristics can be obtained that decrease the injection rate at the injection start and increase the injection rate gradually toward the injection end.
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