| 摘要 |
PURPOSE:To dissolve insufficient strength of an insulation coated layer and improve reliability on insulation, by a method wherein flow marks are put on the opposite sides of the outer circumference of a conductor core wire to each other and an inner and outer double insulation coated layer is extrusion-molded. CONSTITUTION:An insulation coated layer 36 of a conductor core wire 37 is formed into an inner and outer doubleness, the insulation coated layer 36 possesses flow marks 18, 19 on the opposite sides of the core wired 37 each other and formed into an inner and outer doubleness. The flow marks 18, 19 of its inner and outer layers 38, 39 are constituted so that they do not superposed upon each other by forming like this. With this construction, even if a longitudinal crack is generated in one side layer along its flow mark, since a part of the other layer where the flow mark is not formed is in existence, generation of the longitudinal crack extending over the whole thickness of the inner and outer layers 38, 39 can be prevented. Therefore, when this coated layer structure is adopted, the title production is released from various restrictions by extrusion operation conditions and a coated electric wire having favorable insulation properties can be manufactured. |
