| 摘要 |
PROBLEM TO BE SOLVED: To prevent insulation breakdown between the high-voltage side and the low-voltage side and to provide a highly reliable ignition coil. SOLUTION: A dummy coil 513 is wound between a collar part 510b and a collar part 510c formed on the side of a terminal plate 34 of a secondary spool 510 and electrically connects a secondary coil 512 and the terminal coil 513. Since the outer surface of the dummy coil 513 forms the cylindrical shape, the facing area of the dummy coil 513 as a whole confronting the low-voltage side of an ignition coil 2 is large. Therefore, the intensity of the electric field in the vicinity of the dummy coil 513, on which a high voltage is applied, is weak. Thus, trees are not generated in an epoxyresin 29 between the dummy coil 513 and the low voltage side. Therefore, the insulation between the dummy coil 513 and the low-voltage side is excellently held, and the reliability of the ignition coil 2 can be maintaned. |
