Patent ID: 11891972
Assignee: DENSO CORPORATION
Field: Engines, pumps, turbines (Mechanical engineering)
Classification: CPC F  H | IPC F  H

Claim 0:
1. An ignition device for an internal combustion engine, comprising:
an ignition plug;
a primary coil that includes a predetermined winding;
a secondary coil configured to be magnetically linked to the primary coil and be connected to the ignition plug;
a main ignition circuit configured to supply and interrupt a current through the primary coil to accordingly cause a spark discharge to occur in the ignition plug;
an energy supply circuit configured to supply and stop electrical energy to the predetermined winding of the primary coil to accordingly cause the spark discharge to continue;
a recirculation circuit configured to permit and prohibit current recirculation through a recirculation path including the predetermined winding and the recirculation circuit, wherein a current recirculated in the recirculation path is configured to be conducted from an end of the predetermined winding through the recirculation circuit and then to another end of the predetermined winding; and
a controller configured to:
control the main ignition circuit,
send an interruption signal to the main ignition circuit to thereby cause the main ignition circuit to interrupt the current through the primary coil, and
determine a start time of a permission of the current recirculation by the recirculation circuit using, as a trigger, the interruption signal, and start the permission of the current recirculation at the determined start time when the current through the primary coil is interrupted, and
end the permission after a predetermined time period has elapsed since the start time.