ENGINE KNOCK DETECTOR

PURPOSE:To sufficiently detect the generation of knock even when the resonance frequency of the knock changes by conducting sampling with a frequency twice the resonance frequency or above included in the knock. CONSTITUTION:An engine knock detector has sensors 12, 17-19i with sufficient sensitivities over a band including the characteristic frequency of knock and means for catching a signal by an amplifier with a amplification factor which compensates for the frequency characteristics of the sensors, conducting sampling with a frequency twice a resonance frequency or above included in a knock signal, calculating the sum of the absolute values or the squared values of individual sampled values and obtaining the strength of the knock signal. Since, the above-described construction can sufficiently catch the frequencies produced when the knock is generated by the combination of the sensors with sufficient sensitivities over the broad band including the characteristic frequency of the knock and the amplifier, the above-described construction can calculate actual knock energy and can sufficiently detect the generation of the knock even for a change in the resonance frequency of the knock.