Patent ID: 6997171
Filing Date: 2006-02-14
Classification: F02P,Y02T

Abstract:
1. An ignition apparatus for an internal combustion engine, comprising: an electronic control unit that outputs an ignition signal for controlling ignition timing; an igniter connected to receive said ignition signal from said electronic control unit so as to generate an ignition high voltage in a secondary coil of an ignition coil by interrupting a current flowing through a primary coil of said ignition coil through the action of a switching element based on said ignition signal, convert a secondary current flowing through said secondary coil into a fail signal in accordance with ignition of said igniter, and output the fail signal to said electronic control unit; and a signal line on which said ignition signal and said fail signal are both transmitted; said igniter comprising: a primary waveform shaping circuit connected with said signal line and having an input connected in parallel to an input resistance so that when said ignition signal flows into said input resistance, a voltage at said input becomes higher than a prescribed reference voltage thereby to turn on said switching element; and a pulse output circuit connected to said input of said primary waveform shaping circuit and having an output for generating said fail signal into which said secondary current is converted, said pulse output circuit being operable to adjust a current value for said fail signal in such a manner that the voltage at said input of said primary waveform shaping circuit at the time when said fail signal flows into said input resistance becomes less than said prescribed reference voltage.