Ignition system for IC engine - has programmed digital control controlling duration of primary current flow through ignition coil

摘要

The ignition system has a digital control to initiate the current in the primary winding of the ignition coil at a moment in time dependent on an engine parameter. A timing device is started when the primary current is initiated and interrupts the primary current after a given delay. The digital control contains an empirically programmed digital memory and at least two converters responding to different engine parameters and addressing the memory. The memory produces a digital signal describing the time required to initiate the primary current. A counter counts the memory's output and an oscillator of fixed frequency counts out the counter's contents.