A connection device (60) for connecting a first power supply (41) and a second power supply (31) to an ignition plug (1) has a first power supply side line (71) which establishes electrical connection between the ignition plug (1) and the first power suppl...

There is provided an igniting semiconductor device such that it is possible to reliably prevent burning of an IGBT or ignition coil L, and erroneous ignition, even when reducing the size of a capacitor that generates a self-interrupting circuit time consta...

An ignition system (31) includes a spark plug (1), a discharge power supply (32), and an AC power supply (33). The spark plug (1) includes an insulator (2) having an axial hole (4), an electrode (8) disposed in the axial hole (4) and having a tip end locat...