| 摘要 |
PURPOSE:To improve the ignition performance by applying the DC high voltage which is lower than the dielectric breakdown voltage and higher than the continuous discharge voltage for the time from before capacitive electric discharge to a prescribed time after ignition, in an ignition system through diode-distribution. CONSTITUTION:Each negative, positive high voltage is generated from an ignition coil 31 by an ignition signal supplied from an ignition control circuit 2, and is applied onto the corresponding spark plugs 51-54 through the high withstand-voltage diodes 32-36 arranged reversely each other. In a DC high-voltage generating circuit, these positive and the negative high voltages generates a voltage lower than the dielectric breakdown voltage and higher than the continuous discharge voltage which are generated in the gap of the spark plug, during the time from before the start of electric discharge to a prescribed time after the start of electric discharge and within a prescribed crank angle. Then, the ignition coil 31 reduces the first energy by increasing the generated voltage and performs continuous electric discharge aucceeding to the capacitive discharge, and supplies the stabilized energy into the spark plug. Therefore, even if the compression ratio increases and the breakdown voltage increases, the superior ignition performance can be maintained. |
