Patent ID: 7778764

Claim:
A fuel injection control apparatus for a multi-fuel engine, which is configured to control an injection quantity of an alcohol-mix fuel to said engine based on a measured oxygen concentration in an exhaust gas, the fuel injection control apparatus comprising: an oxygen sensor which is configured to measure an oxygen concentration in the exhaust gas, and to output a signal corresponding to the measured oxygen concentration; an alcohol concentration-determining apparatus which is configured to determine an alcohol concentration in the fuel, based on the measured oxygen concentration; a basic injection map which is configured to set a basic injection quantity of the fuel for a plurality of operation states of the engine; said basic injection map being recorded on a recordable medium; an alcohol concentration coefficient table which is configured to set an alcohol concentration coefficient for a plurality of combinations of the basic injection quantity of the fuel and the alcohol concentration of the fuel; said alcohol concentration coefficient table being recorded on a recordable medium; an injection quantity selector which is configured to select a currently applicable basic injection quantity, corresponding to a current operation state of the engine, from the basic injection map; an alcohol concentration coefficient selector, which is configured to select the alcohol concentration coefficient corresponding to the alcohol concentration of the fuel and the basic injection quantity of the fuel from the alcohol concentration coefficient table; and an applied injection quantity calculator, which is configured to calculate an applied fuel injection quantity based on the basic injection quantity and the alcohol concentration coefficient.