A first coil constitutes a first coil unit by placing an iron core plate between the first coil and an auxiliary yokes and engaging stopping parts provided in two holding members to an end surface in an axial direction of the auxiliary yoke. A second coil constitutes a second coil unit by forming magnetic path members by insertion to a resin member provided in a second bobbin unitarily, and fixing two terminals to the resin member. The first and the second coil units are united by connecting one terminal lead line of the first coil taken out from holding members to the first terminal, and connecting another terminal lead line to a surface of the magnetic path member.