Patent ID: 7669459

Claim:
A knocking determination device for an internal combustion engine, comprising: a vibration detecting unit that detects vibrations of an internal combustion engine; a first extracting unit that detects, from said detected vibrations, vibrations at a predetermined frequency band; a second extracting unit that extracts, from said detected vibrations, vibrations at a frequency band that is broader than said predetermined frequency band and includes said predetermined frequency band; a waveform detecting unit that detects a waveform of the vibrations with predetermined crank angle intervals, based on the vibrations extracted by said second extracting unit; a storage unit that stores in advance a waveform of vibrations of said internal combustion engine; and a determining unit that determines whether knocking occurred in said internal combustion engine or not, based on a result of comparison between said detected waveform and said stored waveform as well as on a magnitude of the vibrations extracted by said first extracting unit.