| 摘要 |
PROBLEM TO BE SOLVED: To provide an ignition coil in an internal combustion engine with good durability and reliability by preventing cracks caused by stresses a bobbin or near the bobbin. SOLUTION: An ignition coil 14 includes a center core 17 in a case 16, a side core 18, a secondary coil 19, a primary coil 20, an igniter 21, and a terminal 22. Each magnet 24 is provided on both sides of the center core 17, and a stress attenuating member 25 for covering the magnet 24 and the center core 17 is provided. The center core 17, the magnet 24, and the stress attenuating member 25 are included in a secondary bobbin 26. A resin film 24 with a minute porous face for covering the opening edge part of the secondary bobbin 26 is provided. The secondary bobbin 26 has a hollow space 35 adjoining the stress attenuating member 25 at an inner edge part, and the hollow space 35 functions as a relief space for the stress attenuating member 257 when the stress attenuating member 25 is swollen or shrunk. |
