| 摘要 |
PROBLEM TO BE SOLVED: To sufficiently insulate the primary coil and the secondary coil of an ignition coil having the primary and the secondary coils from each other, by changing the height of the flanges of the secondary coil gradually or by stages in accordance with the upper end faces of the secondary windings. SOLUTION: A secondary bobbin 10 is divided into each winding sections by flanges 12 (12A-12C) having different heights, and a winding 20 is wound in each section. On the bobbin 10, the heights of the flanges from low pressure-side flanges 12C to middle pressure-side flanges 12A are maintained at nearly equal high levels, and the heights of the flanges from the flanges 12A to high pressure-side flanges 12B are made lower by stages as going to the flanges 12B. In addition, the height differences H1 between the low pressure-side flange 12C at one end of the bobbin 10 and the upper end face of the winding 20 and between the middle pressure-side flange 12A near the center of the bobbin 10 and the upper end face of the winding 20 are adjusted so that the height differences H1 can always become nearly equal to the height difference H2 between the high pressure-side flange 12B and the upper end face of the winding 20, with the height differences H1 and H2 being maintained at about 1mm or less. Therefore, the insulating distance between the primary and the secondary coils can be prevented from becoming extremely short. |
