Ignition system for IC engines - measures ignition coil current and closing angle control circuit lengthens interrupter open period accordingly

摘要

The system has an ignition coil, an interrupter in series with its primary winding, and a battery. A closing angle control circuit is controlled by a pickup synchronously with the engine speed, for the interrupter control. A measurement circuit (22) detects a switching-on signal proportional to the current flowing through the primary winding (16) when the interrupter is closed. This signal is stored, and the closing angle control circuit (12) is controlled by the measurement circuit (22) signal, so that the interrupter (14) opening period is lengthened when the ignition coil current increases.