Device for determining engine knocking intensity from detected variations in engine cylinder internal pressure

A knocking detector for an engine provided with a crankshaft and combustion chamber, comprising:

• means for detecting regularly a combustion pressure in said combustion chamber and outputting a corresponding pressure waveform,
• means for eliminating high frequency components from said waveform,
• means for extracting high frequency components from said waveform,
• means for detecting a running state of said engine,
• means for detecting a rotation angle of said crankshaft,
• means for computing a total amount of heat generated in said combustion chamber during one revolution of said crankshaft based on the waveform processed by said high frequency component eliminating means, and on the running state of said engine,
• means for setting a reference level regarding the extracted high frequency components based on the running state of the said engine,
• means for determining a knocking heat start point during one revolution of said crankshaft based on the extracted high frequency components and the reference level set by said setting means,
• means for setting a knocking heat end point during one revolution of said crankshaft;
• means for computing a knocking heat generated during one revolution of said crankshaft based on the knocking heat start point and end point, and on the waveform processed by said high frequency component eliminating means,
• means for determining a knocking intensity based on the total amount of heat and knocking heat.