| 摘要 |
PURPOSE:To discriminate the intensity and polarity of an external magnetic field cross-linking to a saturable magnetic core, by moving the center axis of symmetric saturation characteristics by flowing a bias current through coils wound around the saturable magnetic core. CONSTITUTION:A saturable iron core 1 has three coils 2a, 2b and 2c; the coil 2a is supplied with an AC signal from an oscillating circuit 3, and the coil 2c with a bias current from a bias power source 4. An AC signal detected by the coil 2b is compared with a reference voltage Es by a comparing circuit 5 to discriminate its level. Here, applying a positive or negative bias current moves the center axis of the saturation characteristics of the magnetic core 1 to or from an external magnetic flux (phi). For this purpose, the value of the bias current is set properly for the external magnetic flux (phi) to be detected, so that the external magnetic flux (magnetic field) (phi) having intensity including polarity can be discriminated by the comparing circuit 5. |
