Patent ID: 8834765
Filing Date: 2014-09-16
Classification: H01F,Y10T

Abstract:
1. A method of manufacture for an encased coil body which is to be provided in a state of being embedded in an inner portion of a core containing a soft magnetic powder, in which the encased coil body includes an electric coil which is configured by winding a wire in a state where an insulating layer is interposed between layers of the wound wire, and an electrically insulating thermoplastic resin material which encases the electric coil in a state of entirely enclosing the electric coil from the outside, the method comprising: injection-molding a resin covering layer which encases the coil with the resin material, wherein the injection-molding is conducted such that said injection-molding is divided into a primary molding and a secondary molding, wherein the primary molding includes contacting a primary molding die for the resin covering layer with an inner circumferential surface or an outer circumferential surface of the coil, and injecting the resin material into a primary molding cavity of the primary molding die which is formed on the outer circumferential side or the inner circumferential side of the coil in a state where the coil is constrained by the primary molding die so as to be positioned in a radial direction in the inner circumferential surface or the outer circumferential surface, thereby molding a primary molded body which includes an outer circumferential covering portion or an inner circumferential covering portion in the resin covering layer and also integrating the primary molded body and the coil, wherein the secondary molding includes, after the primary molding, setting the primary molded body along with the coil to a secondary molding die for the resin covering layer, and injecting the resin material into a secondary molding cavity of the secondary molding die which is formed on the inner circumferential side or the outer circumferential side of the coil, thereby molding a secondary molded body which includes the inner circumferential covering portion or the outer circumferential covering portion in the resin covering layer and also integrating the secondary molded body, the coil, and the primary molded body; and after the secondary molding, integrating the encased coil body with the core.