Patent ID: 7472688
Filing Date: 2009-01-06
Classification: F02P,Y02T

Abstract:
1. An ignition device for an internal combustion engine comprising: an exciter coil that is provided in an AC generator which rotates in synchronism with the engine, and generates an AC voltage once for one turn of a crankshaft of said engine, said AC voltage having a half wave of a positive voltage and a half wave of first negative voltage generated before the half wave of said positive voltage and a half wave of second negative voltage generated after the half wave of said positive voltage; an ignition capacitor provided on a primary side of an ignition coil and charged to one polarity by said positive voltage; a discharge switch that conducts when receiving an ignition signal and discharges charges accumulated in said ignition capacitor through a primary coil of said ignition coil; and an ignition control portion that provides the ignition signal to said discharge switch in an ignition position of said internal combustion engine, wherein said ignition control portion comprises: start completion determination means for determining whether said internal combustion engine is at the start or has completed the start; start time ignition control means for arithmetically operating an ignition position detecting time data which is a time to be measured for detecting an ignition position of the engine when the rotational position of said engine and a generation position of said second negative voltage are met and controlling a generation position of said ignition signal by immediately starting measurement of the arithmetically operated time data so that the ignition position of said engine is set in a position suitable at the start of the engine, wherein said time data is a time required for said engine to rotate from a generation position of said second negative voltage to the ignition position suitable at the start of the engine at a rotational speed calculated from time between when said first negative voltage is generated and when said second negative voltage is generated; idling time advance angle control permission condition determination means for determining whether an idling time advance angle control permission condition is met that is a condition for permitting idling time advance angle control to advance an ignition position during idling immediately after completion of the start of said engine from an ignition position during idling in normal operation in order to stabilize idling immediately after completion of the start of said engine; idling time advance angle control means for controlling the generation position of said ignition signal so that when said idling time advance angle control permission condition determination means determines that the idling time advance angle control permission condition is met, the ignition position during idling immediately after completion of the start of said engine is advanced from the ignition position during idling in normal operation; and normal operation time ignition control means for controlling the generation position of said ignition signal so that when said start completion determination means determines that said internal combustion engine has completed the start, and said idling time advance angle control permission condition determination means determines that the idling time advance angle control permission condition is not met, said ignition position is set in a position suitable in normal operation of said internal combustion engine.