MAGNETIC OSCILLATION SENSOR

To provide a magnetic oscillation sensor capable of solving common technical problems of a flux-gate type magnetic sensor such as suppression of leakage flux from an exciting coil, suppression of electromagnetic interference, environmental conservation of a measured magnetic field in the vicinity of the magnetic sensor, miniaturization and densification of the exciting coil.SOLUTION: A magnetism sensitive unit 1000 is configured to detect magnetism by a saturable magnetic body 10, exciting coils 201 to 200+n for generating an exciting magnetic field until each of positive and negative magnetic saturation points of the saturable magnetic body 10 is reached, and annular current circuits 300 to 300+n for suppressing leakage magnetic flux of the exciting magnetic field emitted from the exciting coils 201 to 200+n. A magnetic oscillation sensor 2 is configured by connecting sensor circuit units A1 to An for outputting an exciting current that reverses a polarity at every timing when the saturable magnetic body 10 is magnetically saturated to the exciting coils 201 to 200+n, and various problems in suppression of leakage flux from the exciting coils 201 to 200+n and miniaturization and densification of the exciting coil are solved.SELECTED DRAWING: Figure 6 【課題】フラックスゲート方式の磁気センサにおける共通的な技術的課題、すなわち、励磁コイルからの漏れ磁束抑制、電磁的干渉の抑制、磁気センサ近傍における測定磁場の環境保全、励磁コイルの小型化と密集化などを可能とする磁気発振センサを提供する。【解決手段】可飽和磁性体１０と、可飽和磁性体１０の正負の各磁気飽和点に到達するまでの励磁磁界を発生する励磁コイル２０１～２００＋ｎと、励磁コイル２０１～２００＋ｎから放出される励磁磁界の漏れ磁束を抑制する環状電流回路３００～３００＋ｎとをもって磁気を検出する磁気感応部１０００を構成し、可飽和磁性体１０が磁気飽和するタイミング毎に極性反転する励磁電流を出力するセンサ回路部Ａ１～Ａｎを励磁コイル２０１～２００＋ｎに接続して磁気発振センサ２を構成して、励磁コイル２０１～２００＋ｎからの漏れ磁束抑制、励磁コイルの小型化と密集化における諸課題を解決した。【選択図】図６