An ignition device includes a coil unit and an igniter. The coil unit includes a primary coil and a secondary coil. The primary coil includes a main primary coil and an auxiliary primary coil formed by winding a single primary conductor on a primary bobbin. The secondary coil is formed by winding a secondary conductor on a secondary bobbin. A DC voltage is applied to an intermediate section of the primary conductor between the main primary coil and the auxiliary primary coil. The igniter controls current flowing into the main primary coil or the auxiliary primary coil. The primary bobbin includes a bobbin body and a hooking part protruding from the bobbin body. The main primary coil and the auxiliary primary coil are wound on an outer peripheral surface of the bobbin body to the same direction. A part of the intermediate section is hooked on the hooking part.

An ignition device includes a coil unit and an igniter. The coil unit includes a primary coil and a secondary coil. The primary coil includes a main primary coil and an auxiliary primary coil formed by winding a single primary conductor on a primary bobbin. The secondary coil is formed by winding a secondary conductor on a secondary bobbin. A DC voltage is applied to an intermediate section of the primary conductor between the main primary coil and the auxiliary primary coil. The igniter controls current flowing into the main primary coil or the auxiliary primary coil. The primary bobbin includes a bobbin body and a hooking part protruding from the bobbin body. The main primary coil and the auxiliary primary coil are wound on an outer peripheral surface of the bobbin body to the same direction. A part of the intermediate section is hooked on the hooking part.

Described is a supply circuit for a corona ignition device, with an input for connection to a direct voltage source, a first converter, a second converter, and an output for connecting a load. The two converters each generate an output voltage, which is provided on its secondary side and exceeds the input voltage. The two converters each contain a transformer that galvanically separates the primary side of the converter from its secondary side. At least one transistor switch is arranged between the input and primary side of the two converters for pulse width-modulation of the input voltage. The primary side of the second converter is connected in parallel with the primary side of the first converter, the secondary side of the second converter is connected in series with the secondary side of the first converter, the secondary sides of the two converters are each bridged in this series connection by at least one diode, so that an output voltage can be provided at the output of the supply circuit even given a failure of one of the two converters.

Described is a supply circuit for a corona ignition device, with an input for connection to a direct voltage source, a first converter, a second converter, and an output for connecting a load. The two converters each generate an output voltage, which is provided on its secondary side and exceeds the input voltage. The two converters each contain a transformer that galvanically separates the primary side of the converter from its secondary side. At least one transistor switch is arranged between the input and primary side of the two converters for pulse width-modulation of the input voltage. The primary side of the second converter is connected in parallel with the primary side of the first converter, the secondary side of the second converter is connected in series with the secondary side of the first converter, the secondary sides of the two converters are each bridged in this series connection by at least one diode, so that an output voltage can be provided at the output of the supply circuit even given a failure of one of the two converters.

An ignition device capable of more reliably protecting a primary winding of an ignition coil from high temperature is provided. The ignition device includes an ignition coil, a switching element, a temperature sensor, and a thermal cutout circuit. A primary winding of the ignition coil is connected to a DC power supply and the switching element. The temperature sensor is provided to measure the temperature of the switching element. The thermal cutout circuit forcibly turns off the switching element when the temperature of the switching element becomes higher than a predetermined forcible turn-off temperature Toff. The thermal cutout circuit is configured to lower the forcible turn-off temperature Toff when the power supply voltage Vb of the DC power supply decreases.

An ignition device capable of more reliably protecting a primary winding of an ignition coil from high temperature is provided. The ignition device includes an ignition coil, a switching element, a temperature sensor, and a thermal cutout circuit. A primary winding of the ignition coil is connected to a DC power supply and the switching element. The temperature sensor is provided to measure the temperature of the switching element. The thermal cutout circuit forcibly turns off the switching element when the temperature of the switching element becomes higher than a predetermined forcible turn-off temperature Toff. The thermal cutout circuit is configured to lower the forcible turn-off temperature Toff when the power supply voltage Vb of the DC power supply decreases.

An ignition coil unit includes: an ignition circuit including a primary coil and a secondary coil; a power generator including a generator coil; a controller configured to control an ignition timing of the ignition circuit by an input signal generated by an induced voltage of the generator coil; and a sensor configured to input load information to the controller. The controller includes a memory configured to store working time information which corresponds to operating information based on the input information and the load information, as matrix data composed of the operating information, the load information and time data.

An ignition coil unit includes: an ignition circuit including a primary coil and a secondary coil; a power generator including a generator coil; a controller configured to control an ignition timing of the ignition circuit by an input signal generated by an induced voltage of the generator coil; and a sensor configured to input load information to the controller. The controller includes a memory configured to store working time information which corresponds to operating information based on the input information and the load information, as matrix data composed of the operating information, the load information and time data.

An internal combustion engine ignition coil includes: a center core; a primary coil provided on an outer side of the center core; a secondary coil provided on an outer side of the primary coil; and a side core provided on an outer side of the primary coil and the secondary coil and formed by stacked electromagnetic steel sheets, the side core having one contact portion in contact with one end surface of the center core and another contact portion in contact with another end surface of the center core with a magnet therebetween. The side core is composed of a plurality of side core portions fitted to each other to be movable relative to each other in a longitudinal direction of the center core.

An internal combustion engine ignition coil includes: a center core; a primary coil provided on an outer side of the center core; a secondary coil provided on an outer side of the primary coil; and a side core provided on an outer side of the primary coil and the secondary coil and formed by stacked electromagnetic steel sheets, the side core having one contact portion in contact with one end surface of the center core and another contact portion in contact with another end surface of the center core with a magnet therebetween. The side core is composed of a plurality of side core portions fitted to each other to be movable relative to each other in a longitudinal direction of the center core.