PURPOSE: To improve the finish of injection in the completion of injection and prevent the occurrence of noises by fitting slidably a spill pressure absorbing piston for absorbing pressure in an injection pump chamber in the completion of injection in a spill pressure absorbing cylinder.
CONSTITUTION: An unit injector 1 is provided with a pressure cylinder 2, an injection cylinder 3, a nozzle holder 4 and a holder nut 5. A spill absorbing chamber 102 is constituted from the lower surface of a spill pressure absorbing piston 101 slidably fitted in a spill pressure absorbing cylinder 300 and a nozzle holder 4. In the completion of fuel injection, pressure in an injection pump chamber 15 is absorbed by said piston 101. Thus, the secondary injection is prevented to improve the finish of injection while reducing noises.
TOMIJIMA HITOSHI