IGNITION DEVICE

摘要

This ignition device 1 has a spark plug 2 and an ignition coil 3. The spark plug 2 has a plug terminal 22 projecting toward the base end side from a ceramic insulator 23. The ignition coil 3 has a coil body part 30 provided with a primary coil 31 and a secondary coil 32, and a helical spring 33 that electrically connects the secondary coil 32 and the plug terminal 22. The plug terminal 22 is formed of a material having conductivity and magnetism, and has a terminal body part 221 of which the outer diameter is larger than the inner diameter of the spring 33, and a terminal extension part 222 of which the outer diameter is smaller than the inner diameter of the spring 33 and that extends from the terminal body part 221 toward the base end side. A leading end section 331 of the spring 33 is in contact with the terminal body part 221. The terminal extension part 222 is inserted inside the inner side of the spring 33. An insulation member 4 is interposed between the outer circumferential surface of the terminal extension part 222 and the inner circumferential surface of the spring 33.