Abstract: An ignition coil for internal combustion engines including a primary core formed in a shape of rectangular ring and fixed on the inner peripheral edge of the bottom wall of a casing, a secondary core having a main portion of which is formed in a shape of straight beam, a primary winding assembly having a primary bobbin formed on the main portion of the secondary core, and a secondary winding assembly. Both winding assemblies are housed in an internal space of the casing, and a synthetic resin is filled in the internal space of the casing and cured. In the side wall of the casing is formed a rectangular opening portion which opens at the top end; and on the primary bobbin a rectangular closing member is formed integrally therewith. When the opening portion of the casing is closed with the closing member, both end faces in the longitudinal direction of the secondary core formed in the primary bobbin face to the inside peripheral surfaces of the primary core.

Abstract: The invention is directed to an ignition coil for use in an internal combustion engine. The ignition coil includes a center core which has a plurality of core members aligned. At least one permanent magnet is disposed between the core members. A primary winding and a secondary winding are mounting on the center core and permanent magnet. The permanent magnet is enclosed in the primary winding at least. An outer core having at least one core member is disposed around the primary winding and secondary winding. One end of the outer core is connected to one end of the center core, wheras the other end of the outer core is connected to the other end of the center core.