| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide an ion current detecting device for an internal combustion engine, which detects ion current even in an internal combustion engine having a discharge function with an ignition plug and performing combustion without discharge, while requiring no external power supply for ion current detection. <P>SOLUTION: An engine control device ECU which outputs an ignition signal to an ignition coil 1 so as to supply a discharge current to a discharge plug, causes the ignition coil 1 to function as a DC-DC converter booster circuit by supplying a DC-DC driving signal of short period energization signal to an ignition switching element 1c at an arbitrary timing, and charges an ion current detection power supply capacitor 2a by rectifying voltage of several hundred voltage continuously generated by a charging circuit 3 at the DC-DC converter operation to be applied to a secondary coil 1b, thereby allowing ion current detection by the ion current detection circuit 2 without discharge current. <P>COPYRIGHT: (C)2012,JPO&INPIT</p> |
