| 摘要 |
A magnetic sensor comprises a bobbin (31) having one surface provided with a toroidal groove (31a), and a toroidal inductor accommodated in the groove. The toroidal inductor comprises a toroidal core (36) and an excitation coil wound on the toroidal core. The excitation coil comprises a conductive pattern of a plurality of thin-film linear conductors individually extending in a radial direction on the one surface of the bobbin and on inner side and bottom surfaces of the toroidal groove with a predetermined angular space, a toroidal core received in the groove, and a plurality of connecting wires each of which is bridged over the toroidal groove and and core interconnects an inner end of one of the thin-film linear conductors and an outer end of a next adjacent one of the thin-film linear conductors. The conductive pattern and the connecting wires are connected into a toroidal coils as excitation coil wound around the toroidal core. Thus, the toroidal inductor is formed in the toroidal groove. The connecting wire may be formed as a conductor pattern on a printed circuit board. In another embodiment, the toroidal inductor may be formed on a printed circuit board, and the toroidal inductor is accommodated in the groove of the bobbin without the conductive patter by coupling the printed circuit board onto the bobbin. <IMAGE> |
