Patent ID: 7710231

Claim:
An ignition coil comprising: a coil body including a center core made of a soft magnetic material, a primary coil and a secondary coil, which are accommodated in a coil case; a plug connection portion protruding from the coil body, the plug connection portion being adapted to bring a high-voltage side winding end of the secondary coil into conduction with a spark plug; a connector for electrically connecting the coil body to an outside of the coil case; an igniter arrangement portion for arranging an igniter including a switching control circuit for energization and non-energization to the primary coil; an outer peripheral core made of a soft magnetic material and arranged on an outer peripheral side of the secondary coil; and an intermediate core made of a soft magnetic material and arranged between the outer peripheral core and an end of the center core in the axial direction, wherein the primary coil is arranged on an inner peripheral side of the secondary coil, and the center core is arranged on an inner peripheral side of the primary coil, wherein the secondary coil includes a secondary electric wire having thereon an insulating film, wound around an outer periphery of a resinous secondary spool, wherein the connector is formed integrally with an end of the secondary spool in an axial direction, wherein the igniter arrangement portion is formed integrally with the secondary spool, wherein the connector is formed integrally with the igniter arrangement portion and the secondary spool, while protruding from the igniter arrangement portion, and wherein the intermediate core is arranged in a core arrangement concave portion that is provided between the end of the secondary spool in the axial direction and the igniter arrangement portion.