| 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 8 a 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 8 a, is reduced and reaches a saturation value thereof. |
