A plasma generating device that improves plasma generating efficiency can further accommodate changes in plasma generating state because of changes in conditions of surroundings and the like. The plasma generating device is provided with an electromagnetic wave radiating device, which has an electromagnetic wave generating device that oscillates electromagnetic waves and a radiating antenna that radiates electromagnetic waves oscillated by the electromagnetic wave generating device, and a control device that controls the electromagnetic wave radiating device. The electromagnetic wave radiating device is provided with a power detector that detects traveling wave power output by the electromagnetic wave generating device and reflected wave power reflected from the radiating antenna, and the control device automatically controls the oscillation pattern for the electromagnetic waves on the basis of the proportion of the value for the reflected wave power to the value for the traveling wave power detected by the power detector.

A multipoint spark plug includes side electrodes provided in a pair so as to extend in a lengthwise direction of a tip end portion via a gap, and an intermediate electrode provided in the gap between the pair of side electrodes such that a plurality of ignition gaps are formed in the lengthwise direction of the tip end portion. An electrode holding portion is formed from separate parts that hold the side electrodes and the intermediate electrode, respectively, so as to insulate the side electrodes and the intermediate electrode from the main body portion, and the respective parts thereof project into the combustion chamber from the tip end portion.

A multipoint spark plug for igniting an air-fuel mixture in a combustion chamber of an engine includes a main body portion that is formed in a flattened shape and inserted into an insertion hole of the engine such that a tip end portion thereof opposes the combustion chamber, a pair of side electrodes provided via a gap in a lengthwise direction of the tip end portion, and at least one intermediate electrode provided in the gap between the pair of side electrodes such that a plurality of ignition gaps are formed in the lengthwise direction of the tip end portion.

An ignition coil for an internal combustion engine is equipped with an assembly of a connector casing and a coil body. The coil body includes a primary winding wound around a primary spool. The connector casing has terminals each of which is equipped with a conductor fastener. The conductor fastener has a slit in which one of ends of the primary winding is fit to make an electric connection between the terminal and the primary winding. The primary spool has conductor guides and a backup support to establish alignment of each of the ends of the primary winding with one of the conductor fasteners and also to facilitate insertion of each of the ends of the primary winding into one of the conductor fasteners when the coil body is fitted into the connector casing, thereby ensuring the stability of electric connection between the primary winding and the terminal.

An ignition coil for an internal combustion engine is equipped with an assembly of a connector casing and a coil body. The coil body includes a primary winding wound around a primary spool. The connector casing has terminals each of which is equipped with a conductor fastener. The conductor fastener has a slit in which one of ends of the primary winding is fit to make an electric connection between the terminal and the primary winding. The primary spool has conductor guides and a backup support to establish alignment of each of the ends of the primary winding with one of the conductor fasteners and also to facilitate insertion of each of the ends of the primary winding into one of the conductor fasteners when the coil body is fitted into the connector casing, thereby ensuring the stability of electric connection between the primary winding and the terminal.

A power supply device includes a power supply configured to supply DC power, and a PMIC configured to convert DC power provided from the power supply and to provide the converted DC power to an SoC, wherein the PMIC is provided with a plurality of rails configured to output different voltages.

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 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.

In an ignition coil for an internal combustion engine, a resistor is disposed in a tower insertion hole of a high-voltage tower section. A coil spring is inserted in the tower insertion hole. An inner diameter of a proximal end side portion of the tower insertion hole is larger than an outer diameter of a maximum outer diameter portion of the resistor. An inner diameter of the distal end side portion of the tower insertion hole is larger than an outer diameter of a proximal end side portion of the coil spring, and is smaller than the outer diameter of the maximum outer diameter portion. In a state where the coil spring is pulled out from the tower insertion hole, the maximum outer diameter portion is restrained by the distal end side portion of the tower insertion hole, and a gap is formed between the resistor and a high-voltage cap.

An ignition apparatus includes a spark plug having a high voltage electrode and an external electrode facing each other across a gap and being configured to generate a spark discharge in the gap to ignite a combustible fuel mixture in a combustion chamber of an internal combustion engine, an ignition coil device configured to generate a predetermined high voltage and supply the high voltage to the high voltage electrode to form a path for the spark discharge in the gap, a high frequency power supply having a band-pass filter and being configured to supply an alternating current to the spark discharge path, and a control device configured to control operation timing of the high frequency power supply. The band-pass filter passes a frequency of from 1 MHz to 4 MHz.