PURPOSE: To improve a response characteristic of acceleration, by providing an injection rate control mechanism variably controlling a fuel injection rate and a control device controlling the injection rate control mechanism when an engine is accelerated.
CONSTITUTION: A fuel injection nozzle 10 provides an injection rate control mechanism 35 variably controlling a fuel injection rate. The nozzle 10 arranges the end of a plunger member 36 oppositely facing to a piston part 33a and applies the pressure of fuel from a fuel introducing port 26 acting on the rear end surface of the member 36. A control device 44 controls the nozzle 10 in such a manner that leak fuel is discharged only by the first fuel discharge passage 37 by closing a solenoid operated opening and closing valve 39 when an engine is accelerated from its low speed operation or the engine is low load operation while the leak fuel is discharged both by the first and second fuel discharge passage 37, 38 by opening the solenoid operated opening and closing valve 39 when the engine is accelerated from its high speed operation or the engine is in intermediate load operation. In this way, a response characteristic of acceleration can be improved by expediting a rise of the supercharger pressure in the initial time of acceleration.
HITASE FUMIO
YOSHIOKA SADASHICHI
MATSUOKA TAKESHI
