| 摘要 |
PURPOSE:To enable to prevent deterioration of fuel consumption ascribable to the prevention of knocking by correcting ignition timing through a judgment of knocking with an envelope signal, in a captioned ignition controller controlling the ignition timing with a knocking sensor signal. CONSTITUTION:A signal 31 of a knocking sensor 11 is rid of a noise, amplified, turned into an envelope signal 33 through an envelope detecting circuit 20 and entered into a computor 21 after a conversion from analog to digital. Now, an area between an evelope and a zero level is read and a knocking condition is judged by the signal and ignition timing is corrected. This judgement procedure is that a noise signal is first discriminated through an interruption request signal, an analog to digital conversion value is cumulatively added and stored as an envelope area. This cumulative addition value judges that knocking is not generated when it is less than fixed value and delays the ignition timing so that the value corresponds to its level when the value is more than the fixed value. |
