Patent ID: 7945379

Claim:
A knock determination device for an internal combustion engine, comprising: a knock sensor detecting a vibration of said internal combustion engine; and an operation unit operative to extract from the detected vibration a vibration of a first frequency band including a frequency of vibration occurred by knocking and excluding a resonance frequency of said internal combustion engine, extract from the detected vibration a vibration of a second frequency band including said first frequency band and said resonance frequency of said internal combustion engine and being broader than said first frequency band, detect a waveform of a vibration at predetermined crank angle intervals, as based on said vibration of said second frequency band, store in advance a waveform serving as a reference in waveform for vibration of said internal combustion engine, and determine whether said internal combustion engine knocks, as based on a result of comparing the detected waveform with the stored waveform and an intensity of said vibration of said first frequency band.