Patent ID: 7779673

Claim:
A device for determining knocking of an internal combustion engine, comprising: a crank position sensor detecting a crank angle of said internal combustion engine; a knock sensor detecting magnitude of vibration of said internal combustion engine to correspond to the crank angle; and an operation unit connected to said crank position sensor and said knock sensor, wherein said operation unit detects a waveform of vibration in a predetermined interval of the crank angle based on the magnitude of vibration of said internal combustion engine, said operation unit calculates for each predetermined crank angle a difference in magnitude of vibration between the detected waveform and a waveform model predetermined as a reference waveform of vibration of said internal combustion engine, when a difference in magnitude greater than a predetermined value is present and number of said difference in magnitude greater than the predetermined value is equal to or smaller than a predetermined number, said operation unit corrects the detected waveform, when the difference in magnitude greater than the predetermined value is present and the number of said difference in magnitude greater than the predetermined value is equal to or smaller than the predetermined number, said operation unit determines whether or not knocking has occurred in said internal combustion engine based on a result of comparison between the corrected waveform and the waveform model, and when the difference in magnitude greater than the predetermined value is present and the number of the difference in magnitude greater than the predetermined value is greater than the predetermined number, said operation unit determines whether or not knocking has occurred in said internal combustion engine based on a result of comparison between the detected waveform and the waveform model.