Patent attributes
A coil bobbin has a cylindrical portion around which a coil winding is wound. The coil winding is composed of coil members of an end-defined ring shape coupled to each other. The cylindrical portion is inserted into openings of the coil members along a direction of a center axis of the cylindrical portion and from one end of the cylindrical portion. Flanges protruding outwardly relative to the center axis of the cylindrical portion are integrally provided at the other end of the cylindrical portion and a bobbin-side engagement portion for engagement between the coil bobbin and the coil winding is formed on a face of the flange opposed to the coil member. As the cylindrical portion is inserted into the coil members, the bobbin-side engagement portion comes into engagement with a winding-side engagement portion formed on a back face of the coil member.