| 摘要 |
PURPOSE:To achieve the reduction of noise and NOx by setting the primary injection stroke and the min. sectional area of a fuel leak part to each arbitrary value. CONSTITUTION:A parallel groove 35 is formed on the outer peripheral surface 25 of the head part 24 of a plunger 14, and the min. sectional area Amin of the fuel leak part which communicates to the parallel groove 35 and the plunger top surface can be adjusted, and the primary injection stroke can be adjusted. Therefore, the two-stage injection characteristic and the initial stage injection characteristic in an arbitrary operation region can be improved by setting the min. sectional area Amin of the fuel leak part and the primary injection stroke to each arbitrary value, and the reduction of noise and NOx can be achieved. |
