| 摘要 |
PROBLEM TO BE SOLVED: To enable an independent ignition type ignition coil device to be applied to an engine with a plastic head cover by improving thermal shock resistance and electric field concentration relaxation (insulation characteristic) between a secondary coil and a center core of the independent ignition type ignition coil device. SOLUTION: There is a secondary coil 3 in a primary coil 5, and a soft epoxy 17 is charged between a secondary bobbin 2 and a center core 1. In the secondary bobbin 2, a low-pressure side of the secondary coil is an injection side of the soft epoxy 17, and an inner diameter thereof has a gradient so as to have a difference in inner diameters such that the low pressure side of the secondary coil is larger and a high pressure side of the secondary coil is smaller, so that the wall thickness of the low-pressure side of the secondary coil of the secondary bobbin is made smaller, and that of the high pressure side is made larger. The soft epoxy 17 is provided with a recessed part 17' by pressure molding, and has Tg that satisfies a condition of [allowable stress of the secondary bobbin > generating stress at (-40 deg.C - glass transition temperature Tg of insulating resin)]. |
