| 摘要 |
PURPOSE:To prevent the occurrenc of knocking and to prevent breakage of an engine, by a method wherein an output during the period of the given crank angle of a knocking detecting means is determined, an upper limit value is set to a value which is smoothed by weighting the determined output, knocking is separated from the smoothed value, and the computing value is compared with given comparison reference. CONSTITUTION:The output of the given crank angle period of a knocking detecting means (a) is determined by a determining means (c), and a value obtained by smoothing the determined output by means of a smoothing means (d) through weighting of it produces background noise. The smoothed value and the determined value are divided and subtracted, and meanwhile, knocking is further separated from the background noise. The computing value is compared with a given comparison reference value, and an upper limit value is set by an upper limit value set means (e) to the smoothed value. Thus, the magnitude of knocking is accurately discriminated, a smoothed value during the occurrence of abnormality is prevented from abnormal increase, knocking is prevented from occurring with excellent precision, and an engine is pevented from the occurrence of breakage due to preignition. |
