| 摘要 |
PURPOSE:To secure a fuel injection quantity and a fuel injection rate either in time of high supercharging as well as to aim at acceleration in the atomization of injection fuel and its distributability in time of low supercharging, by letting a lift control starting position of a needle valve vary according to a degree of supercharging pressure. CONSTITUTION:A supercharging pressure signal out of a supercharging pressure sensor 22 is inputted into a control unit 23 at a step S1, while a duty solenoid of a pressure control valve 21 is driven according to a duty ratio at a step S4 through steps S2 and S3, and fuel pressure to be impressed on a plunger member 18 is controlled by the pressure control valve 21, then returned to the step S1 for repetition. And, in case of high supercharging pressure, a high duty ratio signal is fed to the pressure control valve 21 from the control unit 23 but since the fuel pressure to the plunger member 18 is low and does not receive the control of a lift position, a fuel injection quantity to an engine is secured, thus improvements in engine output is well promotable. What is more, when the supercharging pressure is low, the fuel pressure is high the other way whereby time for duel injection at high speed is long enough, thus improvements in distributability is well promotable. |
