Patent ID: 6557526
Filing Date: 2003-05-06
Classification: F02D,F02P,Y02T

Abstract:
An ignition timing control device for use with an internal combustion engine, the engine performing a combustion of an air-fuel mixture in a combustion chamber according to an ignition by a spark plug, comprising:a sensor which detects an operating condition of the engine; and a programmable controller programmed to: calculate a reaction probability which expresses a combustibility of the air-fuel mixture in the combustion chamber on the basis of the operating condition; calculate a combustion rate of the air-fuel mixture in the combustion chamber on the basis of the operating condition; calculate an air-fuel mixture combustion period on the basis of a combustion chamber volume at a combustion start timing, the reaction probability and the combustion rate to cause the combustion period to be longer as the combustion chamber volume increases, to cause the combustion period to be shorter as the reaction probability increases, and to cause the combustion period to be shorter as the combustion rate increases; calculate a target ignition timing by subtracting the combustion period from a first predetermined timing which is later than the combustion period start timing; and control an ignition timing of the spark plug to coincide with the target ignition timing.