| 摘要 |
<p>PURPOSE:To prevent a failure of ignition by providing a dust core composed of soft magnetic powder and insulating material, and primary and secondary windings wound on the dust core. CONSTITUTION:An ignition coil includes a dust core 11 composed of soft magnetic powder and insulating material, and primary and secondary windings 3 and 4 wound on the dust core 11. The dust core can be made by press-molding soft magnetic powder with insulating organic binder; the soft magnetic powder may include Fe, Fe-Si, Fe-Al-Si, Fe-Ni, or Fe-Co. Such a dust core has smaller eddy current loss at high frequencies because of the insulating material. Therefore, the drop in the secondary voltage due to high frequency excitation is reduced to prevent a failure to spark.</p> |
