摘要 |
PURPOSE:To improve fuel consumption during idle operation and stabilize combustion during use of lean fuel mixture and EGR, by providing a DC-DC converter for enhancing ignition energy in an ignition device of a halting system. CONSTITUTION:An induction high voltage is generated on a secondary side of an ignition coil 1 at its block timing, and ignition plugs 2b and 2d for a first and fourth cylinders are broken down between electrodes thereof by high voltage diodes D1 and D4 to start discharging. At this time, discharge current due to high voltage V0 charged without delay in a capacitor C5 of a DC-DC converter 15 flows along a loop formed by a steering diode D8, P1, 2b, 2d, P4 and D9. Accordingly, a sustained discharge time of the discharge current is rendered long, thereby increasing discharge energy. |