Coil ignition circuit for IC engines - controls energising phase by different criteria for low and high engine rotational speeds

摘要

The ignition system includes an emitter of control signals with an associated threshold value switch. The switch regulates a control stage having a storage member the stored energy of which decreases with increasing engine speed. There is an electronic switch in series with the primary winding of the ignition coil, which at the ignition point interrupts the primary current supplied by a DC source. The quantity of energy stored in the storage member is sensed and upon attainment of the predetermined thresh-old value of change-over is effected such that the point of switching on of the ignition coil is determined by the emitter voltage and not by the duration of the discharge of the capacitor.