JPH0449806U

JPH0449806U -

Info

Publication number: JPH0449806U
Application number: JP9251990U
Authority: JP
Priority date: 1990-09-03
Filing date: 1990-09-03
Publication date: 1992-04-27

Description

[Brief explanation of drawings]

第１図はこの考案の一実施例を示す渦電流式ギ
ヤツプ検出装置の構成図、第２図は、この考案の
一実施例のギヤツプセンサ、ハイパスフイルタ、
ローパスフイルタの信号波形図、第３図は従来の
渦電流式ギヤツプ検出装置の構成図、第４図はギ
ヤツプセンサの等価回路図である。図中、１は測定物、２はギヤツプセンサ、３は
芯材、４はコイル巻き導線、５は発振器、６は定
電流回路、７はハイパスフイルタ、８はローパス
フイルタ、９は整流平滑回路、１０は抵抗検出回
路、１１は補償回路、１２は演算回路、１３はコ
イル巻き導線の直流抵抗ｒ_１、１４はコイル巻き
導線のインダクタンスＬ_１、１５は測定物の直流
抵抗ｒ_２、１６は測定物のインダクタンスＬ_２で
ある。なお、図中同一あるいは相当部分には同一
符号を付して示してある。 FIG. 1 is a block diagram of an eddy current gap detection device showing an embodiment of this invention, and FIG. 2 shows a gap sensor, a high-pass filter, and a high-pass filter according to an embodiment of this invention.
A signal waveform diagram of a low-pass filter, FIG. 3 is a configuration diagram of a conventional eddy current type gap detection device, and FIG. 4 is an equivalent circuit diagram of a gap sensor. In the figure, 1 is the object to be measured, 2 is a gap sensor, 3 is a core material, 4 is a coiled conductor, 5 is an oscillator, 6 is a constant current circuit, 7 is a high pass filter, 8 is a low pass filter, 9 is a rectifier smoothing circuit, 10 is a resistance detection circuit, 11 is a compensation circuit, 12 is an arithmetic circuit, 13 is the DC resistance r ₁ of the coiled conductor, 14 is the inductance L ₁ of the coiled conductor, 15 is the DC resistance r ₂ of the object to be measured, and 16 is the object to be measured. The inductance _L2 is. It should be noted that the same or corresponding parts in the figures are indicated by the same reference numerals.

Claims

[Scope of utility model registration request]

An eddy current gap detection device includes a gap sensor configured by winding a coil around a core material, an oscillator connected to the gap sensor for oscillating operation,
A constant current circuit that is connected to this oscillator and sends a constant current to the gap sensor through the oscillator, and a high pass filter that extracts only the oscillation component from the output of the oscillator.
Similarly, there is a low-pass filter that extracts only the DC component from the output of the oscillator, a rectifier and smoothing circuit that rectifies and smoothes the high-frequency output of the high-pass filter, a resistance detection circuit that detects the resistance of the gap sensor from the DC output of the low-pass filter, and a resistance detection circuit that detects the resistance of the gap sensor from the DC output of the low-pass filter. An eddy current gap detection device comprising: a compensation circuit that compensates for temperature using the output of a resistance detection circuit; and an arithmetic circuit that computes the output of the compensation circuit into a gap length.