JPS56129819A - Eddy current type mold level meter with agc - Google Patents

Eddy current type mold level meter with agc

Info

Publication number
JPS56129819A
JPS56129819A JP3338780A JP3338780A JPS56129819A JP S56129819 A JPS56129819 A JP S56129819A JP 3338780 A JP3338780 A JP 3338780A JP 3338780 A JP3338780 A JP 3338780A JP S56129819 A JPS56129819 A JP S56129819A
Authority
JP
Japan
Prior art keywords
voltage
feedback
controlled oscillator
detecting coil
eddy current
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
JP3338780A
Other languages
Japanese (ja)
Other versions
JPS624645B2 (en
Inventor
Kazuo Sano
Seigo Ando
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
JFE Engineering Corp
Original Assignee
NKK Corp
Nippon Kokan Ltd
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by NKK Corp, Nippon Kokan Ltd filed Critical NKK Corp
Priority to JP3338780A priority Critical patent/JPS56129819A/en
Publication of JPS56129819A publication Critical patent/JPS56129819A/en
Publication of JPS624645B2 publication Critical patent/JPS624645B2/ja
Granted legal-status Critical Current

Links

Classifications

    • G—PHYSICS
    • G01—MEASURING; TESTING
    • G01F—MEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water
    • G01F23/26—Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm by measuring physical variables, other than linear dimensions, pressure or weight, dependent on the level to be measured, e.g. by difference of heat transfer of steam or water by measuring variations of capacity or inductance of capacitors or inductors arising from the presence of liquid or fluent solid material in the electric or electromagnetic fields

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Electromagnetism (AREA)
  • Power Engineering (AREA)
  • Thermal Sciences (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)
  • Measurement Of Length, Angles, Or The Like Using Electric Or Magnetic Means (AREA)
  • Continuous Casting (AREA)

Abstract

PURPOSE:To enable the molten steel level to be measured with high accuracy by controlling the feedback amount of a feedback amplifier according to the reactance variation of a detecting coil caused by eddy current generated in the mold side wall. CONSTITUTION:To a feedback amplifier 7 having a feedback circuit formed from a parallel resonance circuit consisting of a positive feedback resistor RP, a capacitor CO and a detecting coil 8, an AC voltage having a constant amplitude as well as a frequency approximately equal to the resonance frequency of said resonance circut is applied from a voltage-controlled oscillator 5. Then, the output of said amplifier 7 is also applied to a phase detector 6, to which the output of said voltage-controlled oscillator 5 is also applied to detect the phase difference between these applied input voltages, and a DC voltage according to said phase difference is applied to said voltage-controlled oscillator 5. Thereby, the error in measuring distance due to the temperature change of the detecting coil 8 is compensated, and the degree of accuracy can be increased.
JP3338780A 1980-03-18 1980-03-18 Eddy current type mold level meter with agc Granted JPS56129819A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP3338780A JPS56129819A (en) 1980-03-18 1980-03-18 Eddy current type mold level meter with agc

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP3338780A JPS56129819A (en) 1980-03-18 1980-03-18 Eddy current type mold level meter with agc

Publications (2)

Publication Number Publication Date
JPS56129819A true JPS56129819A (en) 1981-10-12
JPS624645B2 JPS624645B2 (en) 1987-01-31

Family

ID=12385175

Family Applications (1)

Application Number Title Priority Date Filing Date
JP3338780A Granted JPS56129819A (en) 1980-03-18 1980-03-18 Eddy current type mold level meter with agc

Country Status (1)

Country Link
JP (1) JPS56129819A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61239120A (en) * 1985-04-16 1986-10-24 Nippon Kokan Kk <Nkk> Method and device for calibrating electromagnetic induction type level meter
KR100421573B1 (en) * 1999-11-01 2004-03-10 가부시키 가이샤 노켄 Capacitance type detector
CN101865718A (en) * 2009-04-17 2010-10-20 深圳迈瑞生物医疗电子股份有限公司 Liquid level detection circuit, device and calibration method thereof
EP2980538A1 (en) * 2014-08-01 2016-02-03 Nireco Corporation Eddy current mold level measuring device and mold level measuring method

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS61239120A (en) * 1985-04-16 1986-10-24 Nippon Kokan Kk <Nkk> Method and device for calibrating electromagnetic induction type level meter
JPH0367578B2 (en) * 1985-04-16 1991-10-23 Nippon Kokan Kk
KR100421573B1 (en) * 1999-11-01 2004-03-10 가부시키 가이샤 노켄 Capacitance type detector
CN101865718A (en) * 2009-04-17 2010-10-20 深圳迈瑞生物医疗电子股份有限公司 Liquid level detection circuit, device and calibration method thereof
EP2980538A1 (en) * 2014-08-01 2016-02-03 Nireco Corporation Eddy current mold level measuring device and mold level measuring method
US9816851B2 (en) 2014-08-01 2017-11-14 Nireco Corporation Eddy current mold level measuring device and mold level measuring method

Also Published As

Publication number Publication date
JPS624645B2 (en) 1987-01-31

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