PURPOSE: To control a closed angle with ease by use of a cylinder discriminating signal having a phase lag and double frequency wave form against an ignition signal which decides energizing condition, which actuates to control mutually a simultaneous ignition coil.
CONSTITUTION: Signal rotors 7a and 7b rotate with 1/2 revolution of internal combustion engine, allowing an ignition signal magnetic pick-up 2a to generate 4-cycle AC output with one revolution of a signal rotor 7a. The output permits to shape the wave form by a wave form shaping circuit, allowing the ignition signal and a cylinder discrimination signal to feed into AND gate 10a with one level of respective input signal to make the output one level. AND gate 10b permits the cylinder discrimination signal to feed into an inverted signal and the ignition signal by an inverter 10c with a compounded length of signal to produce. Those signals indicate the wave from with lagged phase making switching transistors 4', 4 turn on.
IYODA MICHIO
HAGA TAKASHI
MAKITA KUNIO
