Patent ID: 7942041
Filing Date: 2011-05-17
Classification: F02D

Abstract:
1. An engine control device that receives crank signals of a pulse train every predetermined angle interval corresponding to a rotation of a crank shaft for an engine, and increments a counter value of a crank counter indicating a rotational angle of the crank shaft, the engine control device comprising: a pulse interval detection means that detects a pulse interval between edges of the crank signals of a pulse train continuously transferred; a missing tooth location detection means that: determines the missing tooth location when the detection result indicates that the first pulse interval division value is not less than the first judgment value; a difference value calculation means that calculates a crank counter difference value by subtracting the counter value of the crank counter when the missing tooth location detection means detects the missing tooth location from a predetermined missing tooth location counter set value which is set in advance as a predetermined set counter value of the crank counter corresponding to the missing tooth location; a missing tooth location detection verifying means that verifies whether or not the detection result of detecting the missing tooth location by the missing tooth location detection means is correct based on the pulse interval detected by the pulse interval detection means; an adjusted counter value calculation means that calculates an adjusted counter value, with which the counter value of the crank counter is updated, based on the crank counter difference value calculated by the difference value calculation means, the current counter value of the crank counter, and an adjusting counter value, which is set in advance based on a timing for rewriting the counter value of the crank counter, when the missing tooth location detection verifying means determines that the detection result by the missing tooth location detection means is correct; and a counter value rewriting means that rewrites the counter value of the crank counter at the rewriting timing with the adjusted counter value after the adjusted counter value is calculated by the adjusted counter value calculation means.