SPIRAL COIL

PROBLEM TO BE SOLVED: To provide a spiral coil which is manufactured at a low cost and reduces the high-frequency loss resulting from the eddy current loss. SOLUTION: A braided wire having a flatly crushed shape wherein strands is insulated, or a plain stitch wire wherein strands is insulated, is wound in such a direction that the surfaces of the longer side are superimposed, or is spirally wound in such a direction that the surfaces of the shorter side are superimposed to constitute the spiral coil. In this case, because an ordinary braided wire or an ordinary plain stitch wire is used, it is manufactured at a low cost and the high-frequency loss is reduced. The spiral coil, which is wound in such a direction that the surfaces of the longer side are superimposed, has more windings with respect to the same coil diameter than that in the round wire case. The spiral coil, which is wound in such a direction that the surfaces of the shorter side are superimposed, has a coil thickness thinner than that in the case wherein a round wire of the same cross-sectional area is used. COPYRIGHT: (C)2009,JPO&INPIT