| 摘要 |
PURPOSE:To obtain the foil-wound transformer having a high insulating performance which is capable of offering a sufficient tension at winding a wire by composing an insulating sheet which is wound together with a metallic sheet out of two kinds of materials which are different in a tensional strength and a hermetic degree. CONSTITUTION:An insulating sheet 18 wound with being inserted between metallic sheets 7 is composed of lamination of a material 18a whose hermetic degree is 4,000 Gurley or below and a material 18b whose tensional strength is 14kg/mm<2> or over. The foil-wound transformer thus constituted can endure enough on the side of material 18b even a tension of about 10kg/mm<2> at winding a wire so that the winding does not become loose after winding the wire or drying. Also as the material 18b can stretch extremely long, the sufficient strength against shrinkage or extension due to a change of temperature can be obtained. Furthermore, because also against various mechanical forces at operation of the foil-wound transformer, the metallic sheets 7 and the material 18a which are interposed function as a cushion and absorb a slip shearing force acting between it and the metallic sheets, a damage on the insulating sheet 18 can be prevented. |
