Capacitor discharge ignition system with inductively extended discharge time

An ignition device for an internal combustion engine, comprising:

• a booster means including a booster coil and a first switching element for generating a boosted voltage from the booster coil;
• a driving signal generating circuit for forming a driving signal for driving the first switching element in response to an ignition signal;
• a first and a second condenser for charging with the boosted voltage from the booster means;
• an ignition coil having a secondary side to which an ignition plug is connected;
• a second switching element forming a first closed circuit for discharge with the first condenser and a primary side of the ignition coil, said second switching element being turned on in synchronism with the ignition signal;
• an inductor forming a second closed circuit with the second condenser, the primary side of the ignition coil and the second switching element;
• a rectifying element connected to the primary side of the ignition coil;
• wherein voltage is generated in the ignition coil by discharging the first and second condensers therethrough in synchronism with the ignition signal, and a discharge energy of the second condenser stored in the inductor is supplied to the primary side of the ignition coil thereby extending a discharge time at the ignition plug;
• and
• a delay means for preventing a turning on of the first switching element during the extended discharge time by outputting a delay pulse in synchronism with the ignition signal to the driving signal generating circuit, thus establishing a third closed circuit for maintaining the extended discharge time through the booster coil, the inductor, the primary side of the ignition coil and the second switching element.