| 摘要 |
PURPOSE:To surely prevent erroneous judgement of knocking by setting a back ground level initial value at the time of entering into a knocking control range, in a ratio type knocking control method using a resonant frequency where knocking control is limited only in a specified operational range. CONSTITUTION:An injector 16 and an ignition coil 13 are respectively controlled by a control unit 9 based on respective detection signals from respective sensors 2, 5, 11, 12, 200 for respectively detecting operational condition of an engine 7. Namely, characteristic component of knocking is extracted and comparison component is calculated so as to judge the knocking based on the detection signal particularly from the combustion condition sensor 200. In this case, the comparison component is calculated only in a specified operational range, and then the calculated value of the comparison component at the time of separation from this range is maintained. On the other hand, the calculated value of the maintained comparison component is compared with a standard value of the comparison component preliminarily determined at the time of reentering into the specified operational range. The larger value can be made the initial value of the comparison component at time of entering. |
