Patent ID: 6328016
Filing Date: 2001-12-11
Classification: F02P,Y02T

Abstract:
A knock suppression control apparatus for an internal combustion engine including at least one cylinder, an ignition circuit for generating a high ignition voltage in conformance with ignition timing, and a spark plug disposed within said cylinder for generating spark discharge within said cylinder upon application of said high ignition voltage, said knock suppression control apparatus comprising:ion current detection means for detecting an ion current flowing by way of said spark plug upon combustion of an air-fuel mixture charged in said cylinder;filter means for extracting a knock signal from an output signal of said ion current detecting means;knock decision means for deciding occurrence of a knock event in said engine on the basis of said knock signal;control quantity correcting means for correcting a control quantity for said internal combustion engine so as to suppress the knock event on the basis of result of decision made by said knock decision means;integrating means for arithmetically determining an integral value which corresponds to an output level of said ion current;comparison level setting means for setting a predetermined comparison reference level for said integral value; andcorrecting quantity arithmetic means for outputting a correcting signal for correcting parameters relevant to said knock decision means or alternatively relevant to said control quantity correcting means on the basis of result of the comparison between said integral value and said comparison reference level,said integrating means including:first integrating means for arithmetically determining an integral value of said knock signal as a first integral value; andsecond integrating means for arithmetically determining an integral value of said ion current as a second integral value,wherein said comparison level setting means is so designed as to set first and second comparison reference levels for said first and second integral values, respectively, andwherein said correcting quantity arithmetic means is so designed as to output said correcting signal at least on the basis of result of the comparison between said first integral value and said first comparison reference level or alternatively at least on the basis of result of the comparison between said second integral value and said second comparison reference level.