Ignition coil

An ignition coil, comprising:

• a center core;
• a primary coil wound around the center core;
• a secondary coil wound around the primary coil;
• a plurality of side cores, which are arranged around the secondary coil, and are coupled to the center core to form a closed magnetic path;
• a magnet inserted between the plurality of side cores;
• an igniter configured to control supply and interruption of a current to the primary coil;
• a case configured to accommodate the center core, the primary coil, the secondary coil, the plurality of side cores, the magnet, and the igniter;
• and
• insulating resin filled in the case,
• wherein the side cores include a wide portion having a larger width in a direction from the center core to the side cores, and a narrow portion having a smaller width than the width of the wide portion,
• wherein the magnet is inserted into the wide portion, and
• wherein the igniter is arranged between the narrow portion and the case.