Abstract: Provided is an ignition coil device for an internal combustion engine, including: an insulating case; an ignition coil device main body accommodated inside the insulating case, the ignition coil device main body including: a coil assembly; a center core arranged on an inner side of the coil assembly along a center axis of the coil assembly; a side core arranged on an outer side of the center core and the coil assembly; and an elastic cover provided to the side core; an igniter, which is accommodated inside the insulating case; and a filler, which is provided so as to fill the insulating case and is hardened, wherein the elastic cover includes: a covering portion configured to cover the side core; and a protruding portion, which protrudes from the covering portion, and is configured to relax a stress generated in the filler.

Abstract: Provided is an ignition coil device for an internal combustion engine, including: an insulating case; an ignition coil device main body accommodated inside the insulating case, the ignition coil device main body including: a coil assembly; a center core arranged on an inner side of the coil assembly along a center axis of the coil assembly; a side core arranged on an outer side of the center core and the coil assembly; and an elastic cover provided to the side core; an igniter, which is accommodated inside the insulating case; and a filler, which is provided so as to fill the insulating case and is hardened, wherein the elastic cover includes: a covering portion configured to cover the side core; and a protruding portion, which protrudes from the covering portion, and is configured to relax a stress generated in the filler.

Abstract: A magnetic path is formed of a center core disposed inside a first coil and second coil, a first side core and second side core disposed outside the first coil and second coil and coming into contact with the center core, and a magnet disposed between the first side core and second side core, wherein a shape of a space formed by a portion of contact between the first side core and second side core is a shape that forms an insertion portion of the magnet disposed obliquely with respect to the magnetic path, and voids perpendicular with respect to the magnetic path at either end portion of the magnet.

Abstract: A magnetic path is formed of a center core disposed inside a first coil and second coil, a first side core and second side core disposed outside the first coil and second coil and coming into contact with the center core, and a magnet disposed between the first side core and second side core, wherein a shape of a space formed by a portion of contact between the first side core and second side core is a shape that forms an insertion portion of the magnet disposed obliquely with respect to the magnetic path, and voids perpendicular with respect to the magnetic path at either end portion of the magnet.