| 摘要 |
PURPOSE:To detect knocking accurately without the effect of noises at the time of ignition, by integrating the knocking frequency component. CONSTITUTION:The output of the knocking frequency component, which is extracted by a knocking-frequency-component extracting means (a) is sequentially integrated in a specified crank angle range including an ignition angle by an integrating means (e). Two absolute angle positions are set by delaying the angles from the ignition angle based on the outputs of a crank-angle detecting means (b) and an ignition-time detecting means (c). Integrated values 3 and 4 at said absolute angle positions are corrected by the amount of increases 2-1 of the integrated values before and the after the ignition by an operating means (f). The ratio between the corrected results is obtained. In a discriminating means (g), a reference value, which is determined by an engine speed from an engine speed detecting means (d) and the ratio obtained before are compared. Thus the presence or absence of the knocking is judged. In this way, the effect of noises at the time of ignition is eliminated, and the knocking can be detected accurately. |
