Ignition timing control apparatus for an internal combustion engine

摘要

An ignition timing control apparatus for an internal combustion engine has an air flow sensor for sensing the air flow rate into the air intake pipe of the engine and producing an electrical output signal in the form of pulses having a frequency which is proportional to the air flow rate, and a crank angle sensor for producing an electrical output pulse each time the crankshaft of the engine is at a prescribed crank angle. A pulse counter counts the number of output pulses from the air flow sensor between consecutive output pulses of the crank angle sensor. A controller controls the current to an ignition coil based on the engine rotational speed and on either the output of the pulse counter, or on the output of a calculating mechanism which calculates the amount of intake air into the cylinders of the engine between consecutive output pulses of the crank angle sensor based on the output of the pulse counter.