| 摘要 |
PROBLEM TO BE SOLVED: To accurately diagnose the abnormality of a knock sensor. SOLUTION: A device A/D converts the output signals of the knock sensor 28 by an A/D conversion part 41 in a period in which an ignition timing is advanced to forcibly generate knock (or in a period in which knock is generated), takes therein the converted output signals, analyzes, with respect to time-frequency, the output signals of the knock sensor 28 by a time-frequency analysis part 42, and extracts vibration intensity varying patterns in a plurality of frequency ranges by simultaneously extracting the data on frequency, time, and vibration intensity from the output signals of the knock sensor 28. Then, the device calculates the quantity of the vibration intensity varying patterns in the frequency ranges started at the same timing. The presence of the abnormality of the knock sensor 28 is determined by confirming whether the quantity is less than a determination threshold or not. COPYRIGHT: (C)2009,JPO&INPIT |
