An ignition coil has a ferromagnetic core with a primary coil surrounding a first portion of the ferromagnetic core and a secondary coil surrounding the second portion of the ferromagnetic core. The secondary coil is wrapped around a bobbin. The bobbin has an interior receiving the second portion of the ferromagnetic core. A form is interposed between the secondary coil and the second portion of the ferromagnetic core. The form extends longitudinally along the second portion of the ferromagnetic core. The form is of a non-ferrous metal material.

An ignition coil device having a simplified configuration is obtained. The ignition coil device includes: a primary bobbin having a first outer side surface and a second outer side surface formed on an outer side with respect to the first outer side surface in a width direction of the ignition coil device; a first primary coil wound around the first outer side surface; and a second primary coil wound across the second outer side surface and an outer side surface of the first primary coil, the first primary coil being formed by solid coiling.

An ignition device includes a case having an opening and a bottom wall, a coil bobbin arranged in the case having a through hole, a first end and a second end, an ignition coil wound around the coil bobbin, a core made of magnetic material and projecting from the opening and from the bottom wall, and extending through the coil bobbin, a retainer having a ring portion and multiple leg portions extending from the ring, and a filling resin in the case. The core extends through the ring portion and the leg portions extend in between an inner surface of the coil bobbin and an outer peripheral surface of the core toward the bottom wall, and the case is filled with the filling resin in a manner that at least a part of the ring portion is not covered by the resin.

An ignition coil for an internal combustion engine is provided.

The ignition coil includes: a primary coil and a secondary coil magnetically coupled to each other; a second spool which the secondary coil is wound around; and a connection terminal connected to a high voltage side of the secondary coil and supported by a terminal support portion provided at the second spool. The terminal support portion includes an insertion hole portion allowing the connection terminal to be inserted in an insertion direction as a coil radial direction. The connection terminal includes a protrusion protruding outside the connection terminal in a direction orthogonally crossing the insertion direction. The protrusion is engaged to the insertion hole portion from inward in the coil radial direction.

A primary coil which includes a primary winding which is wound around a primary bobbin, and a secondary coil which includes a secondary winding which is separately wound around a secondary bobbin which includes a plurality of sections, are provided, and a winding portion of the secondary coil is configured in a state where a maximum winding height is set as 20% through 30% with respect to an axis length winding length.

An ignition coil includes primary and secondary coils, a center core inserted into a center hole of the primary coil and a center hole of the secondary coil, an annular side core that forms a magnetic circuit through which a first magnetic flux A generated by the primary coil by being joined to the center core permeates, and a permanent magnet that is disposed between the center core and the side core and that emits a second magnetic flux B directed opposite to the first magnetic flux A to apply a magnetic bias. The side core includes protruded portions that protrude towards lateral sides of a T-shaped horizontal portion of the center core, and gaps are provided between the lateral sides of the T-shaped horizontal portion of the center core and the protruded portions of the side core.

An internal combustion engine ignition device comprises: a center core; a primary coil wound on the outside of the center core; a secondary coil wound on the outside of the primary coil; a permanent magnet which abuts against one end of the center core and is magnetized in the inverse direction to the direction of a magnetic flux produced by the energization of the primary coil; a side core which is disposed on the outside of the secondary coil with one end abutted against the permanent magnet and the other end abutted against the center core, the side core cooperating with the permanent magnet to form a closed magnetic path; and a heat-resistant and elastic resin covering the side core with an opening at an outer peripheral side. Heat dissipation from the side core to a housing is improved without adversely affecting the dielectric strength voltage of the secondary coil.

An ignition coil includes primary and secondary coils, a center core inserted into a center hole of the primary coil and a center hole of the secondary coil, an annular side core that forms a magnetic circuit through which a first magnetic flux A generated by the primary coil by being joined to the center core permeates, and a permanent magnet that is disposed between the center core and the side core and that emits a second magnetic flux B directed opposite to the first magnetic flux A to apply a magnetic bias. The side core includes protruded portions that protrude towards lateral sides of a T-shaped horizontal portion of the center core, and gaps are provided between the lateral sides of the T-shaped horizontal portion of the center core and the protruded portions of the side core.

An ignition apparatus for an internal combustion engine includes: a spark plug; a first ignition coil and a second ignition coil; a battery; a booster circuit that boosts a voltage supplied from the battery; a power transistor that conducts and interrupts a primary current flowing to a primary coil included in the first ignition coil; a MOSFET that applies and interrupts the voltage boosted by the booster circuit to a primary coil included in the second ignition coil; and an ECU that starts electric discharge by the spark plug by controlling the power transistor, and repeatedly applies and interrupts the voltage boosted by the booster circuit by the MOSFET so that the electric discharge that is started is maintained.

An ignition coil has a core with a longitudinal axis, a secondary winding extending around the core, a sleeve extending around the core, a primary winding wrapped around the sleeve, and a controller connected to the primary winding so as to oscillate alternating current to said primary winding. The secondary winding has a high-voltage end and a low-voltage end. The primary winding is in spaced longitudinal relationship from the secondary winding. Specifically, the primary winding is located longitudinally away from the high-voltage end of the secondary winding. A bobbin is positioned over and around the core. The secondary winding is wrapped around at least a portion of the bobbin.