| 摘要 |
PURPOSE:To permit to operate the engine near the maximum output by a method wherein knocking is counted by pulse trains, ignition timing is controlled to delay angle side corresponding to the number of pulse, spark-advance is advanced along a first integral inclination until generating the knock while the spark-advance is switched to the second - n-th integral inclination when the knock is not generated during a predetermined period of time. CONSTITUTION:When abnormal combustion is generated in a combustion chamber 10, a pressure fluctuation is changed into the amplitude of a vibration wave and is transmitted to a knock sensor 4. Frequency, peculiar to the knock, is discriminated from the output by the band pass filter BPF of a knock detecting unit 5, the output of the filter BPF is averaged by a back-ground level output circuit BGL to find a comparison level for detecting the knock and is compared by a comparator CMP with a knock signal emphasized by a signal amplifier SIG. This output is inputted into the electronic engine control unit 7 through a noise mask gate NWG while the output of a revolving angle sensor 6 is also inputted into the control unit 7 to effect necessary operating process, thereafter, necessary ignition pulse is given to an ignition coil 8. According to this method, the operation of the engine may be effected with lean mixture or by an output increasing means to the critical limit of the knock. |
