| 摘要 |
A device for controlling ignition timing in an internal combustion engine includes a vibration detector responsive to engine vibrations, and comparison means for determining when the output signal of the vibration detector exceeds a base noise output value for that particular cylinder, stored during a previous cycle. The operation of the vibration detector and the comparison means is controlled in response to angular position of the crank shaft so that the base noise value and the detected noise value for each individual cylinder can be determined separately, by defining a given angular position window during which pinging or pre-ignition is likely to occur on any given cylinder. On the basis of the comparison thus effected, the normal ignition advance signal is either unaffected (because no pinging has occurred) or subject to an ignition retardation component (when pinging has occurred) in order to relieve that given cylinder of pinging. Preferably the ignition timing is controlled to have a different value for each cylinder to allow for the possibility of one cylinder being subject to pinging when the others are not. |
