| 摘要 |
<p>PURPOSE:To improve both thermal and impact resistance by inhibiting the inflow of hot-setting resin into a gap between an iron core and a primary coil in an internal combustion engine ignition coil made of hot-setting materials. CONSTITUTION:An attempt is made to lay out a sealing material 8 which covers the upper end of a gap 11 between an iron core 7 and a primary bobbin 1 on the upper end of the iron core 7. A further attempt is made to inject hot- setting synthetic resin, for example, epoxy resin 10 into a case 9 and then heat the resin 10 so that it may hot-set. Before the hot-setting synthetic resin 10 is injected, a sealing material 8 is installed to one end of the iron core 7. The sealing material 8 is designed to cover a gap 11 produced between a bobbin 1 and a primary coil which adjoins the iron core 7. This construction prevents the hot-setting synthetic resin from flowing into a gap when it is injected so that an air layer may be formed in the gap 8. It is, therefore, possible to prevent the generation of thermal stress induced by a differential linear expansion coefficient of the iron core 7 and the hot-setting synthetic resin 10 at the gap between the iron core 7 and the primary bobbin 1, thereby preventing thermal impact resistance.</p> |
