Abstract: An ignition coil for an internal combustion engine includes a magnetically-permeable core a primary winding disposed outward of the core, and a secondary winding disposed outward of the primary winding and inductively coupled to the primary winding. The secondary winding has a left secondary winding section and right secondary winding section. A first end of the left secondary winding section is in electrical contact with a first terminal for delivering a first spark-generating current to a first spark plug. A first end of the right secondary winding section is in electrical contact with a second terminal for delivering a second spark-generating current to a second spark plug. A second end of the first secondary winding and a second end of a the second secondary winding is connected to a third terminal for delivering a third spark-generating current to a third spark plug.

Abstract: An ignition coil for an internal combustion engine includes a magnetically-permeable core extending along a core longitudinal axis, the core having a pair of end surfaces on axially-opposite ends thereof. The ignition coil also includes a primary winding disposed outward of the core, a secondary winding disposed outward of the primary winding, and a structure comprising magnetically-permeable steel laminations having a base and a pair of legs, the structure defining a magnetic return path. The core is disposed between the pair of legs such that the core longitudinal axis extends through the legs and the end surfaces face toward the legs and at least one of the end surfaces of the core is spaced apart from a respective one of the legs to define an air gap. The structure is over-molded with an over-molding material such that the over-molding material fills at least a portion of the air gap.

Abstract: An ignition coil for an internal combustion engine includes a magnetically-permeable core a primary winding disposed outward of the core, and a secondary winding disposed outward of the primary winding and inductively coupled to the primary winding. The secondary winding has a left secondary winding section and right secondary winding section. A first end of the left secondary winding section is in electrical contact with a first terminal for delivering a first spark-generating current to a first spark plug. A first end of the right secondary winding section is in electrical contact with a second terminal for delivering a second spark-generating current to a second spark plug. A second end of the first secondary winding and a second end of a the second secondary winding is connected to a third terminal for delivering a third spark-generating current to a third spark plug.

Abstract: An ignition coil for an internal combustion engine includes a magnetically-permeable core extending along a core longitudinal axis, the core having a pair of end surfaces on axially-opposite ends thereof. The ignition coil also includes a primary winding disposed outward of the core, a secondary winding disposed outward of the primary winding, and a structure comprising magnetically-permeable steel laminations having a base and a pair of legs, the structure defining a magnetic return path. The core is disposed between the pair of legs such that the core longitudinal axis extends through the legs and the end surfaces face toward the legs and at least one of the end surfaces of the core is spaced apart from a respective one of the legs to define an air gap. The structure is over-molded with an over-molding material such that the over-molding material fills at least a portion of the air gap.

Abstract: An ignition coil engages an inner surface of a bore of an engine, the providing access to a spark plug. The engagement is a boltless cam-lock engagement. A spring is associated with the engagement to hold the assembly in tension, and the spring also contacts a ground terminal in the ignition coil and the base of the spark plug to provide a short electrical path for radiofrequency interference (RFI) dissipation.

Abstract: An ignition apparatus includes a cylindrical core made from magnetically-permeable material and a C-shaped magnetic return path structure that is made from a stack of silicon steel laminations. A tightly controlled air gap is provided between one leg of the C-shaped structure and an end face of the core, forming a magnetic circuit having a high magnetic permeability, which overall reduces the number of primary winding turns needed, thereby reducing the amount of copper wire. In addition, the circular cross-section of the core reduces the mean length per turn (MLT) of the primary winding because the primary winding can be wound directly on the core, which in turn also reduces the MLT of the secondary winding. The reduced MLT also reduces the amount of copper wire. The structure may be replaced using a magnetically-permeable, U-shaped shield.

Abstract: An ignition apparatus includes a cylindrical core made from magnetically-permeable material and a C-shaped magnetic return path structure that is made from a stack of silicon steel laminations. A tightly controlled air gap is provided between one leg of the C-shaped structure and an end face of the core, forming a magnetic circuit having a high magnetic permeability, which overall reduces the number of primary winding turns needed, thereby reducing the amount of copper wire. In addition, the circular cross-section of the core reduces the mean length per turn (MLT) of the primary winding because the primary winding can be wound directly on the core, which in turn also reduces the MLT of the secondary winding. The reduced MLT also reduces the amount of copper wire. The structure may be replaced using a magnetically-permeable, U-shaped shield.

Abstract: An ignition coil engages an inner surface of a bore of an engine, the providing access to a spark plug. The engagement is a boltless cam-lock engagement. A spring is associated with the engagement to hold the assembly in tension, and the spring also contacts a ground terminal in the ignition coil and the base of the spark plug to provide a short electrical path for radiofrequency interference (RFI) dissipation.

Abstract: An ignition coil has a primary core supporting a primary winding that is connectable to an engine ignition system and a secondary winding inductively couplable to the primary winding and surrounding the primary winding. The secondary winding can be connected to an engine spark plug assembly. A flux director surroundingly engages the core. The flux director is a single, unitary piece of steel that is not made of composite Iron particles.