| 摘要 |
An ignition coil comprises a housing, a rod-shaped center core 54 arranged substantially at the center within the housing, a thermal stress relaxing member 52 covering the outer circumferential surface of the center core 54, a cylindrical spool 4 arranged on the outer circumferential side of the thermal relaxing member 52 with a gap 9 in between and a resin insulating material 8a with which the gap 9 is filled and which hardens. The thermal stress relaxing member 52 is wound around the center core 54 and the thickness of the thermal stress relaxing member 52 is set to a thickness so that the thermal stress, which is caused by the thermal deformation of the center core 54 and is applied to the resin insulating material 8a, is reduced and reaches a saturation value thereof. |
