INSULATION COIL FOR OIL-FILLED ELECTRIC APPLIANCE

摘要

PROBLEM TO BE SOLVED: To reduce the cost of the insulation materials of an interlayer insulation layer provided between respective insulated conductor layers wherein wound windings are included, in an insulation coil for oil-filled electric appliances. SOLUTION: The structure of an interlayer insulation layer 5 is composed of two layers. One layer is a thin and cheap polypropylene film 6 and the other is a kraft paper 7 which has an enough tensile strength for the circumferential tensile force applied during winding.