Patent ID: 6230546
Filing Date: 2001-05-15
Classification: F02P,G01L

Abstract:
A method of detecting knocking combustion in an internal combustion engine having at least one combustion chamber operating in a succession of combustion cycles, comprising the following steps carried out for a respective present one of said succession of said combustion cycles:a) sensing an ionic current in said combustion chamber and providing an ionic current signal corresponding to said ionic current;b) processing said ionic current signal by sampling during a time window and filtering through a band-pass filter to provide a filtered sampled knocking signal;c) integrating said filtered sampled knocking signal to provide a present cycle integrated knocking value;d) generating an intermediate correction value by integrating said ionic current signal;e) forming a present cycle correction value from at least one said intermediate correction value that was generated during a prior one of said combustion cycles preceding said respective present combustion cycle;f) correcting at least one of said signals in said steps b) and c) by arithmetically combining said at least one of said signals with said present cycle correction value, such that said present cycle integrated knocking value provided in said step c) is a corrected integrated knocking value; andg) comparing said corrected integrated knocking value to at least one knocking threshold, and outputting a knock recognition signal if said corrected integrated knocking value exceeds said knocking threshold.