Patent ID: 7143576

Claim:
A fuel injection control device of an internal combustion engine comprising: a fuel injection valve which directly injects fuel into the inside of a combustion chamber of an engine; fuel injection valve control means which calculates a basic fuel injection flow rate which becomes a target air-fuel ratio corresponding to an engine operation state and performs a driving control of the fuel injection valve; a pressure storage chamber which is connected to the fuel injection valve and stores fuel of high pressure therein; a fuel pressure sensor which detects a fuel pressure in the inside of the pressure storage chamber; a high-pressure pump which pressurizes the fuel transported from a fuel tank in the inside of a pressurizing chamber and supplies the fuel of high pressure to the pressure storage chamber; a discharge flow rate control valve for controlling a fuel discharge flow rate supplied to the pressure storage chamber from the high-pressure pump; and fuel pressure control means which performs a feedback control of the discharge flow rate control valve such that the fuel pressure in the inside of the pressure storage chamber which is detected by the fuel pressure sensor agrees with a preset target fuel pressure, wherein the fuel injection control device includes fuel increase correction means which gives an amount increase instruction to the fuel injection control means to increase the basic fuel injection flow rate in a state that a rotational speed of the engine falls in a given preset rotational speed region where the minimum discharge flow rate of the high-pressure pump is expected to exceed zero and the fuel pressure in the inside of the pressure storage chamber is higher than the target fuel pressure.