| 摘要 |
<p>PURPOSE:To effectively cool the central portion of coil without almost changing the whole length and magnetic characteristic of the coil by a method in which a cooling metal fitted with a cooling pipe and plural small coils are laminated and then pinchingly held by an insulating plate. CONSTITUTION:A small coil 1 composed of cnductor windings subjected to an insulating treatment and a C-shaped cooling metal plate 2 whose peripheral ends 2A are brazed with a Cu cooling pipe 4 are alternately laminated. The laminate is put and fixed between two insulating plates 5 of asbestos, etc., from up and down sides. A protective mouth metal 7 with a slit 8 is provided to the inside circular portion of the insulating plates and a heat-treated part to be tempered is inserted through the protective mouth metal 7. Then, it is subjected to a low-frequency tempering treatment. By this apparatus, the damage by baking to the central portion of the coil 1 can be prevented and the durability of the coil can therefore be raised.</p> |
