Patent ID: 7596992

Claim:
A fuel injection control apparatus for an internal combustion engine comprising: a speed sensor that measures a speed of an internal combustion engine; a controller working to control a quantity of fuel to be injected from a fuel injector into the internal combustion engine, when it is required to enter an injection quantity learning mode, said controller controlling the fuel injector to spray a learning injection quantity of the fuel that is a quantity of the fuel to be injected into the internal combustion engine for learning a fuel injection characteristic of the fuel injector, said controller determining an increase in speed of the internal combustion engine through said speed sensor which has arisen from spraying of the learning injection quantity of the fuel and also determining an actual injection quantity of the fuel that is an quantity of the fuel considered as having been sprayed from the fuel injector based on the increase in speed of the internal combustion engine, said controller calculating a correction factor based on a difference between the learning injection quantity and the actual injection quantity for compensating for the difference, said controller also determining a variation in load acting on a driving member of a torque transmission mechanism through which an output torque of the internal combustion engine is transmitted from the driving member to a driven member, when an absolute value of the variation in load is greater than a given value, said controller halting the injection quantity learning mode.