| 摘要 |
PROBLEM TO BE SOLVED: To determine a knock by discriminating noise and knock vibration of an engine. SOLUTION: Output of a knock sensor 28 is separated into a plurality of frequency components by a plurality of band-pass filters with every predetermined crank angle section (with every knock determining section), and for example, a peak value is extracted as a variable for respectively expressing a characteristic of steady noise (for example, injection noise of a fuel injection valve 20) of the engine 11 on the plurality of these frequency components, and an average value of its peak value and dispersion (a standard deviation) are arithmetically operated. The frequency component of a maximum average value is selected from a plurality of arithmetically operated average values, and the existence of noise is determined on the basis of the ratio of the dispersion of its frequency component to the average value. When detecting the noise in any frequency component, a knock determination is prohibited, or ignition timing feedback control based on a knock determining result is prohibited, or the ignition timing may be corrected to be delayed. COPYRIGHT: (C)2006,JPO&NCIPI |
