| 摘要 |
PROBLEM TO BE SOLVED: To attain an appropriate duration regardless of the extent of time course and to facilitate the detection of an ion current by measuring the discharge time in spark discharge and detecting the time course of an ignition plug. SOLUTION: A bias power supply 24 for measuring an ion current is connected to a spark plug 18 via a high-pressure diode 23. While controlling the fuel injection, an electronic controller 6 measures the ion current flowing in each ignition so as to detect the combustion state of an engine 100 and control the combustion state based on the detection results. The combustion state, for example, is so controlled that the occurrence of knock is detected based on the knock signal superimposed on the ion current and in a case of occurring the knock, the ignition time is delayed so as to absorb knocking. A program measuring the duration of the spark discharge generated in impressing high voltage to the spark plug 18 of the engine 100 and detecting the time course of the spark plug 18 based on the measured duration is incorporated in the electronic controller 6. |
