| 摘要 |
<p>PROBLEM TO BE SOLVED: To restrain delamination and crackings from occurring at an interfacial surface in an internal combustion ignition coil, so as to prevent a high- voltage from leaking out of the ignition coil by a method, wherein PPS resin used as the material for a lower case is kept high in adhesive power to an epoxy resin, and stresses caused by thermal expansion coefficient difference is relaxed. SOLUTION: This ignition coil is equipped with a housing 60, where a secondary coil assembly 20 possessed of a built-in inner core 10 is housed, and an insulating material 13 is filled into a gap between the secondary coil assembly 20 and the housing 60. In this case, a lower case 61 is formed of PPS resin, where soft polymer possessed of a bonding functional group such as an epoxy group or a hydroxy group is alloyed into the PPS resin. The lower case 61 which is brought into direct contact with an insulating material 13 is set at 0.7 to 1.5 mm in wall thickness, by which the lower case 61 is enhanced in adhesive power to an epoxy resin used as the insulating material 13 and absorbs the thermal expansion difference and is prevented from being separated.</p> |
