| 摘要 |
PURPOSE:To carry out the charge and pressurization of the fuel for the next injection by carrying out the return operation of a booster piston speedily and correctly by pushing up the booster piston itself for pressurizing fuel directly and compulsorily by utilizing the fuel pressure. CONSTITUTION:After supplied into a pressurizing chamber 6 through a feeding passage 21 from a feeding port 3, fuel is jetted from an injection hole 28 through the outer peripheral chamber of a needle 27. After the completion of the fuel injection, a rod valve 14 is shifted rightward by a spring 19, and a spool 15 is deflected from the position extend over a fuel feeding port 3 and an intermediate passage 13, and at the same time, a fuel return port 4 and the intermediate passage 13 communicate each other. Further, the fuel feeding port 3 and an introducing passage 11 communicates each other through the first outer peripheral groove 16, and at the same time, the communication between a discharge passage 12 and the fuel return port 4 is cut off by the shift of the second outer peripheral groove 17, and fuel is returned into a vacant space 80, and a piston 8 is pressed. Therefore, the piston 8 can perform return operation speedily and correctly. |
