| 摘要 |
PURPOSE:To prevent the generation of mismatching discharge, even when a discharge starting voltage is lowered, by providing a closed loop which is formed for a large capacity of capacitor and its charging and discharging per air cylinder in a plasma ignition unit. CONSTITUTION:From a plasma ignition power source circuit 7, a charging current flows into and charges large capacity of capacitors 8a-8d through diodes 12a-12d and 14a-14d. A spark ignition circuit allows ignition plugs 6a-6d to discharge sparks in serial order. When an ignition timing control circuit 15 supplies a trigger pulse to thyristors 13a-13d respectively, the thyristors 13a-13d are turned on consecutively. A closed loop produced by the turned on thyristors allows the electric current to flow, thereby discahrging plasma. The thyristors 13a-13d are synchronized with only plugs which discharge sparks at a high pressure pulse Vig durig discharging and are triggered, thereby producing a conductivity condition. Therefore, mismatching discharge can be prevented. |
