| 摘要 |
PURPOSE:To enable prevention of unnecessary correction of a delay angle, by a method wherein an ignition timing is delayed for correction only in a knock occurring region discriminated from the value of an in-cylinder pressure maximum timing, based on a knock sensor signal. CONSTITUTION:In-cylinder pressure signals from in-cylinder pressure sensors 1a-1d are switched at each cylinder by means of a multiplexer 3 to extract a signal for a frequency component, equivalent to knock vibration, by means of a hand pass filter 4. A current value is held by means of a peak hold circuit 6, and a knock level is detected therefrom. Meanwhile, the in-cylinder signal is inputted to a control unit 7 through a hand pass filter 5 and an in-cylinder pressure maximum timing is calculated therein. As note above, based on detecting information on an in-cylinder pressure maximum timing, a knock level, running conditions, control of an ignition timing for preventing the occurrence of knocking is effected according to a program. The control causes accurate decision of the occurrence of knocking, and enables prevention of unnecessary correction of a delay angle. |
