Abstract: An ignition transformer for use with a spark ignition system for an internal combustion engine includes a central core, a primary coil, a secondary coil, and a magnetic return. The central core defines a first end and a second end. The primary coil is used to vary magnetic energy into the central core in response to a primary current applied to the primary coil. The secondary coil is used to generate a secondary voltage in response to changes in the magnetic energy in the central core. The magnetic return defines a return-path to couple magnetic energy from the first end to the second end. A permeability value of the return-path is selected so the transformer has a secondary-current versus time-response characteristic that decays to fifty-percent (50%) of an initial secondary current when ten percent (10%) to twenty-five percent (25%) of a burn-time interval has passed.

Abstract: An ignition coil for delivering a spark-generating current to a spark plug includes a magnetically-permeable core; a primary winding disposed outward of the core; and a secondary winding radially surrounding the primary winding and inductively coupled to the primary winding, the secondary winding having a low-voltage end and a high-voltage end. The secondary winding includes a secondary winding first section proximal to the low-voltage end and having a first thickness. The secondary winding also includes a secondary winding second section proximal to the high-voltage end and having a second thickness that is less than the first thickness of the secondary winding first section.

Abstract: An ignition coil for delivering a spark-generating current to a spark plug 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 terminates at one end thereof in a low-voltage end and terminates at another end thereof in a high-voltage end. At least one of the low-voltage end of the secondary winding and the high-voltage end of the secondary winding is electrically connected directly to a terminal through an electrically conductive polymer.

Abstract: An ignition transformer for use with a spark ignition system for an internal combustion engine includes a central core, a primary coil, a secondary coil, and a magnetic return. The central core defines a first end and a second end. The primary coil is used to vary magnetic energy into the central core in response to a primary current applied to the primary coil. The secondary coil is used to generate a secondary voltage in response to changes in the magnetic energy in the central core. The magnetic return defines a return-path to couple magnetic energy from the first end to the second end. A permeability value of the return-path is selected so the transformer has a secondary-current versus time-response characteristic that decays to fifty-percent (50%) of an initial secondary current when ten percent (10%) to twenty-five percent (25%) of a burn-time interval has passed.

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 delivering a spark-generating current to a spark plug includes a magnetically-permeable core; a primary winding disposed outward of the core; and a secondary winding radially surrounding the primary winding and inductively coupled to the primary winding, the secondary winding having a low-voltage end and a high-voltage end. The secondary winding includes a secondary winding first section proximal to the low-voltage end and having a first thickness. The secondary winding also includes a secondary winding second section proximal to the high-voltage end and having a second thickness that is less than the first thickness of the secondary winding first section.

Abstract: An ignition coil 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 includes a left secondary winding section wound clockwise around the primary winding and a right winding section wound counterclockwise around the primary winding. The left secondary winding section has i) a first left winding end distal from the right winding section and ii) a second left winding end that is proximal to the right winding section. The right secondary winding section has i) a first right winding end distal from the left winding section and ii) a second right winding end that is proximal to the left winding section. The second left winding end and the second right winding end are connected to a terminal.

Abstract: An ignition coil for delivering a spark-generating current to a spark plug 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 terminates at one end thereof in a low-voltage end and terminates at another end thereof in a high-voltage end. At least one of the low-voltage end of the secondary winding and the high-voltage end of the secondary winding is electrically connected directly to a terminal through an electrically conductive polymer.

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 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 includes a left secondary winding section wound clockwise around the primary winding and a right winding section wound counterclockwise around the primary winding. The left secondary winding section has i) a first left winding end distal from the right winding section and ii) a second left winding end that is proximal to the right winding section. The right secondary winding section has i) a first right winding end distal from the left winding section and ii) a second right winding end that is proximal to the left winding section. The second left winding end and the second right winding end are connected to a terminal.

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 includes a central core, a primary winding, a spool, a secondary winding, and a case outward of the core, spool, primary winding, and secondary winding. The secondary winding is wound on the spool and includes a high voltage end. The ignition coil also includes a cup formed of a metal material in electrical communication with the high voltage end of the secondary winding and is configured to be contacted by a conductive connector that is suitable for connection to a spark plug. The cup includes a generally cylindrical first sidewall press fit with the case and defining a press fit area at the interface of the first sidewall and the case, a generally cylindrical second sidewall spaced radially from the first sidewall, and an annular space defined between the press fit area and the second sidewall.

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 includes a central core, a primary winding, a spool, a secondary winding, and a case outward of the core, spool, primary winding, and secondary winding. The secondary winding is wound on the spool and includes a high voltage end. The ignition coil also includes a cup formed of a metal material in electrical communication with the high voltage end of the secondary winding and is configured to be contacted by a conductive connector that is suitable for connection to a spark plug. The cup includes a generally cylindrical first sidewall press fit with the case and defining a press fit area at the interface of the first sidewall and the case, a generally cylindrical second sidewall spaced radially from the first sidewall, and an annular space defined between the press fit area and the second sidewall.

Abstract: A spark plug coil assembly includes a primary core inside a secondary winding spool that is formed with a closed end. A terminal is embedded in the closed end of the spool and the secondary windings are terminated to the terminal, with the terminal being couplable to a spark plug. Ignition voltage generated in the secondary windings is thus routed to a center of the secondary windings to terminate at the terminal. No pole piece need be disposed between the primary core and the closed end of the spool.

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.

Abstract: A twin spark ignition apparatus having two high-voltage (HV) outputs incorporates features for balancing load capacitance on each HV output. The ignition apparatus provides a first high-voltage (HV) connection configured for direct mounting on a first spark plug, and a second HV connection for coupling to a second spark plug by way of an HV cable. The HV cable adds capacitance at the second HV output, as compared to a direct mount. The secondary winding is shifted by a predetermined distance, relative to the primary winding, in direction toward the direct mount end of the ignition apparatus. The shifting reduces the internal load capacitance at the second end (top), so that when the capacitance added by the HV cable is considered, the respective load capacitances are balanced. The voltage variation between the two HV outputs is reduced.

Abstract: A twin spark ignition apparatus having two high-voltage (HV) outputs incorporates features for balancing load capacitance on each HV output. The ignition apparatus provides a first high-voltage (HV) connection configured for direct mounting on a first spark plug, and a second HV connection for coupling to a second spark plug by way of an HV cable. The HV cable would adds capacitance at the second HV output, as compared to a direct mount. Various structures are included to offset and balance the additional capacitance attributable to the HV cable so that the capacitance of the first HV connection and the second HV connection are balanced within a range. The voltage variation between the two HV outputs is reduced.