ALTERNATOR SIGNAL USED AS CRANKSHAFT POSITION SENSOR IN SMALL MOTORCYCLE ENGINES

摘要

A method for determining engine rotational position and camshaft phase at all times using the output signal of an engine magneto. There is no need for a conventional independent crank sensor which therefore is deleted from an engine in accordance with the invention, thus reducing the weight and cost of an engine. Instantaneous engine speed variation during the compression stroke and the immediately succeeding power (expansion/combustion) stroke causes an uneven periodicity of the output voltage signal from the magneto, as indicated by the period of the voltage reversals, which period variation is detected by an Engine Control Module and used in programmed algorithms to infer the crankshaft rotational position and speed and the camshaft phase at all times. These determinations may be used, among other purposes, to time fuel injection and ignition coil charging and firing.