Patent ID: 6082344
Filing Date: 2000-07-04
Classification: F02P

Abstract:
An ignition device for an internal combustion engine, for generating a high voltage in a secondary winding of an ignition coil by turning on and off a switching element according to an ignition control signal output from an electronic control unit (ECU) for said internal combustion engine to on-off control a primary current flowing in a primary winding of said ignition coil comprising:a Zener diode connected to a lower-voltage end of said secondary winding of said ignition coil in a reverse direction to an induced voltage generated at a timing of starting supply of said primary current, said induced voltage being defined by the product of a change in voltage between opposite ends of said primary winding and a ratio of turns in said ignition coil, said Zener diode coming into conduction at a voltage lower than said induced voltage at a secondary lower-voltage end of said ignition coil at a primary current supply timing, and at a voltage higher than a difference voltage between a sparking voltage and said induced voltage at the secondary lower-voltage end of said ignition coil at the primary current supply timing.