JPH029862U

JPH029862U -

Info

Publication number: JPH029862U
Application number: JP8789788U
Authority: JP
Priority date: 1988-07-01
Filing date: 1988-07-01
Publication date: 1990-01-22

Description

[Brief explanation of drawings]

第１図は本考案の一実施例を示す回路ブロツク
図、第２図は同実施例においてＴ／τを変化した
ときの微小磁束検出感度の相対感度特性を示すグ
ラフ、第３図乃至第５図は本考案の他の実施例を
示すもので、第３図は回路ブロツク図、第４図は
同実施例の各部の出力波形図、第５図はさらに別
の実施例の回路ブロツク図、第６図は従来の漏洩
磁束探傷法を説明するための構成図、第７図は第
６図における鋼材表面とホール素子との距離に対
する漏れ磁束密度特性を示す特性図、第８図は第
７図の特性を得るための鋼材における欠陥例を示
す図、第９図は従来の各種センサーの磁束密度―
出力電圧特性を示す特性図、第１０図は従来の磁
気抵抗素子の初期バイアス電圧のバラツキを示す
グラフ、第１１図は従来の磁気ダイオードの温度
―出力電圧特性を測定するための測定回路図、第
１２図は第１１図での温度―出力電圧特性を示す
特性図、第１３図は可飽和形磁気センサーによる
測定原理を説明するための回路図、第１４図は第
１３図におけるコイルへの供給電力波形及びコイ
ルの出力電圧波形を示す図、第１５図は第１３図
における強磁性体コアのヒステリシス特性及び透
磁率特性を示す特性図、第１６図及び第１７図は
先願例を示すもので、第１６図は回路ブロツク図
、第１７図は検出感度特性を示すグラフである。１０１，１０８…パルス電圧発生器、１０２，
１０２_１〜１０２_ｎ…抵抗（固定インピーダンス
）、１０３，１０３_１〜１０３_ｎ…磁気センサー
、１０３ａ，１０３_１ａ〜１０３_ｎａ…コイル、
１０４…正電圧ピーク検波器、１０５…負電圧ピ
ーク検波器、１０６…加算器、１１０，１１５…
マルチプレクサ。 Fig. 1 is a circuit block diagram showing an embodiment of the present invention, Fig. 2 is a graph showing the relative sensitivity characteristics of minute magnetic flux detection sensitivity when T/τ is changed in the same embodiment, and Figs. The figures show another embodiment of the present invention; FIG. 3 is a circuit block diagram, FIG. 4 is an output waveform diagram of each part of the same embodiment, and FIG. 5 is a circuit block diagram of yet another embodiment. Fig. 6 is a block diagram for explaining the conventional leakage flux detection method, Fig. 7 is a characteristic diagram showing the leakage flux density characteristics with respect to the distance between the steel material surface and the Hall element in Fig. 6, and Fig. Figure 9 shows examples of defects in steel materials used to obtain the characteristics shown in the figure. Figure 9 shows the magnetic flux density of various conventional sensors.
A characteristic diagram showing output voltage characteristics, FIG. 10 is a graph showing variations in initial bias voltage of a conventional magnetoresistive element, FIG. 11 is a measurement circuit diagram for measuring temperature-output voltage characteristics of a conventional magnetic diode, Fig. 12 is a characteristic diagram showing the temperature-output voltage characteristics in Fig. 11, Fig. 13 is a circuit diagram to explain the measurement principle using the saturable magnetic sensor, and Fig. 14 is a diagram showing the temperature-output voltage characteristics in Fig. 11. A diagram showing the supplied power waveform and the output voltage waveform of the coil, FIG. 15 is a characteristic diagram showing the hysteresis characteristics and magnetic permeability characteristics of the ferromagnetic core in FIG. 13, and FIGS. 16 and 17 show the prior application example. FIG. 16 is a circuit block diagram, and FIG. 17 is a graph showing detection sensitivity characteristics. 101, 108...Pulse voltage generator, 102,
102 ₁ to 102 _n ...Resistance (fixed impedance), 103,103 ₁ to 103 _n ...Magnetic sensor, 103a, 103 _{1 a} to 103 _na ... Coil,
104... Positive voltage peak detector, 105... Negative voltage peak detector, 106... Adder, 110, 115...
multiplexer.

Claims

[Claims for Utility Model Registration] (1) A magnetic sensor formed by winding a coil around a ferromagnetic core, a pulse voltage supply source that supplies positive and negative pulse voltage to the coil of the magnetic sensor via a fixed impedance, 1 detecting the positive and negative peak values of the voltage generated at both ends of the coil;
1. A magnetic measurement device comprising a pair of peak value detection means and an adder that adds the positive and negative peak values detected by both of the peak value detection means and sends out a measurement output. (2) a plurality of magnetic sensors each having a coil wound around a ferromagnetic core; a pulse voltage supply source that supplies positive and negative pulse voltage to the coil of each magnetic sensor via a fixed impedance; A selection means for sequentially and selectively extracting voltages generated at both ends; a pair of peak value detection means for respectively detecting positive and negative peak values of the voltages sequentially extracted by the selection means; and both peak value detection means. 1. A magnetic measurement device comprising: an adder that adds positive and negative peak values of each voltage detected by the sensor and sends out a measurement output corresponding to each of the magnetic sensors. (3) A plurality of magnetic sensors each having a coil wound around a ferromagnetic core, and a pulse voltage supply source that selectively sequentially supplies positive and negative pulse voltages to the coils of each magnetic sensor via a fixed impedance. ,
a selection means for sequentially and selectively extracting the voltage generated at both ends of each coil in synchronization with the supply of pulse voltage from the pulse voltage supply source to each coil; and a selection means for selectively extracting the voltage generated at both ends of each coil in synchronization with the supply of pulse voltage from the pulse voltage supply source to each coil; a pair of peak value detection means for respectively detecting the peak values of;
A magnetic measuring device comprising an adder that adds the positive and negative peak values of each voltage detected by the peak value detection means and sends out a measurement output corresponding to each of the magnetic sensors.