| 摘要 |
<p>PROBLEM TO BE SOLVED: To eliminate a gap between a permanent magnet provided between a laminated iron core inserted in a cylinder part of a primary coil bobbin and wound iron core located on the outer periphery of a secondary coil bobbin and the both iron cores to realize a small-sized, light-weight ignition coil. SOLUTION: This ignition coil includes primary and secondary coil bobbins 3 and 4 of a cylindrical shape, provided concentrically and having primary and secondary coils 1 and 2 respectively, an iron core part forming a closed magnetic path in which the magnetic force lines pass through the cylindrical inner periphery of the primary bobbin 3 and through an outer periphery of the secondary bobbin 4, and a permanent magnet 8 for applying magnetic reverse bias to the iron core part. In the case, the iron core part has a laminated iron core 5 located within the cylinder of the primary bobbin 3 and a wound iron core 6 located to the outer periphery of the secondary bobbin 4, the end face of the permanent magnet 8 provided between the iron cores 5 and 6 on the side of the laminated iron core 5 is formed flat corresponding to the end face of the laminated core 5, and the end face of the magnet provided with the wound core 6 is formed into an arcuate surface corresponding to the inner peripheral surface of the wound core 6.</p> |
