JPH0236170B2 - - Google Patents

Info

Publication number
JPH0236170B2
JPH0236170B2 JP57068679A JP6867982A JPH0236170B2 JP H0236170 B2 JPH0236170 B2 JP H0236170B2 JP 57068679 A JP57068679 A JP 57068679A JP 6867982 A JP6867982 A JP 6867982A JP H0236170 B2 JPH0236170 B2 JP H0236170B2
Authority
JP
Japan
Prior art keywords
level
storage tank
fluid
detector
frequency
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.)
Expired - Lifetime
Application number
JP57068679A
Other languages
Japanese (ja)
Other versions
JPS58186017A (en
Inventor
Nobuo Matsushita
Keishin Furukawa
Masakatsu Fujimoto
Tomoaki Sumya
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.)
Hitachi Ltd
Original Assignee
Hitachi 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 Hitachi Ltd filed Critical Hitachi Ltd
Priority to JP57068679A priority Critical patent/JPS58186017A/en
Publication of JPS58186017A publication Critical patent/JPS58186017A/en
Publication of JPH0236170B2 publication Critical patent/JPH0236170B2/ja
Granted legal-status Critical Current

Links

Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01FMEASURING VOLUME, VOLUME FLOW, MASS FLOW OR LIQUID LEVEL; METERING BY VOLUME
    • G01F23/00Indicating or measuring liquid level or level of fluent solid material, e.g. indicating in terms of volume or indicating by means of an alarm
    • G01F23/22Indicating 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
    • G01F23/26Indicating 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
    • G01F23/263Indicating 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 by measuring variations in capacitance of capacitors

Landscapes

  • Physics & Mathematics (AREA)
  • Engineering & Computer Science (AREA)
  • Power Engineering (AREA)
  • Electromagnetism (AREA)
  • Thermal Sciences (AREA)
  • Fluid Mechanics (AREA)
  • General Physics & Mathematics (AREA)
  • Measurement Of Levels Of Liquids Or Fluent Solid Materials (AREA)

Description

【発明の詳細な説明】 本発明は、レベル指示装置に係り、特に貯槽に
貯蔵され誘電率が変化する流体の貯槽内でのレベ
ル位置の変化を貯槽外部にて指示させるのに好適
なレベル指示装置に関するものである。
DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a level indicating device, and particularly to a level indicating device suitable for indicating a change in the level position of a fluid stored in a storage tank and having a changing dielectric constant outside the storage tank. It is related to the device.

従来のレベル指示装置例を第1図により説明す
る。
An example of a conventional level indicating device will be explained with reference to FIG.

第1図は、単一電極固定による静電容量式レベ
ル指示装置の構成図で、金属性の貯槽10内に
は、流体非浸透性並びに電気絶縁性を有する材料
で形成されたサポート11が垂設されている。サ
ポート11には、高周波電極(以下、電極と略)
12が内設されている。電極12には、高周波電
源13が接続されている。高周波電源13には、
レベル表示装置の電気信号検出器(以下、検出器
と略)14が抵抗15、インダクタンス16を介
し接続されている。電気信号検出器14は、貯槽
10の外壁に接続されている。なお、電気信号検
出器14には、レベル表示装置のレベル表示計
(図示省略)が接続されている。
FIG. 1 is a configuration diagram of a capacitive level indicating device with a fixed single electrode. A support 11 made of a fluid-impermeable and electrically insulating material is suspended in a metal storage tank 10. It is set up. The support 11 has a high frequency electrode (hereinafter abbreviated as electrode).
12 are installed inside. A high frequency power source 13 is connected to the electrode 12 . The high frequency power supply 13 includes
An electrical signal detector (hereinafter abbreviated as "detector") 14 of a level display device is connected via a resistor 15 and an inductance 16. Electrical signal detector 14 is connected to the outer wall of storage tank 10 . Note that a level display meter (not shown) of a level display device is connected to the electric signal detector 14.

貯槽10内に流体が第1図に示すレベルの位置
で貯蔵されているとすれば、流体のレベルの位置
は、貯槽10と電極12との静電容量により検出
器14で電気信号、例えば、電流値を検出し、こ
の電流値をレベル表示計に出力することで指示さ
れる。
If the fluid is stored in the storage tank 10 at the level shown in FIG. Indication is given by detecting the current value and outputting this current value to the level display meter.

このようなレベル指示装置では、貯槽内の温
度、圧力、流体の組成等が変化した場合、流体の
誘電率は、それらに対応して変化するため、流体
のレベルの位置が同一であつても検出器で検出さ
れる電流値に違いが生じ、したがつて、レベル表
示計でのレベル指示が不正確になるといつた欠点
があつた。
In such a level indicating device, when the temperature, pressure, composition of the fluid, etc. in the storage tank change, the dielectric constant of the fluid changes accordingly, so even if the level position of the fluid remains the same, the dielectric constant of the fluid changes accordingly. The drawback was that the current values detected by the detectors varied, resulting in inaccurate level indications by the level indicator.

本発明の目的は、上記欠点を除去することで、
貯槽内に貯蔵されている流体の導電率が変化して
もレベル表示計でのレベル指示を正確に行うこと
ができるレベル指示装置を提供することにある。
The purpose of the present invention is to eliminate the above-mentioned drawbacks,
To provide a level indicating device capable of accurately indicating a level with a level indicator even if the conductivity of a fluid stored in a storage tank changes.

本発明の特徴は、流体非浸透性並びに電気絶縁
性を有する材料で形成され貯槽内に垂設されたサ
ポートと、該サポート内に相隣る高周波電極と電
気絶縁状態を保持し前記サポートの長手方向に複
数個配置された高周波電極と、該高周波電極がそ
れぞれ接続された高周波電源と、抵抗並びにイン
ダクタンスを介し前記高周波電源にそれぞれ接続
され、かつ、前記貯槽にそれぞれ接続された前記
高周波電極の個数に見合う台数の電気信号検出器
と、該電気信号検出器と接続されたデコーダと、
該デコーダ並びに前記電気信号検出器と接続され
た演算器と、該演算器と接続されたレベル表示計
とを具備したことで、貯槽内に貯蔵されている流
体の誘電率が変化してもレベル表示計でのレベル
指示を正確に行えるようにしたことにある。
The present invention is characterized by a support that is made of a fluid-impermeable and electrically insulating material and is vertically disposed in a storage tank, and that maintains an electrically insulated state from adjacent high-frequency electrodes within the support, and that maintains an electrically insulated state from adjacent high-frequency electrodes within the support. A plurality of high frequency electrodes arranged in a direction, a high frequency power source to which the high frequency electrodes are respectively connected, and the number of high frequency electrodes each connected to the high frequency power source through a resistance and an inductance, and each connected to the storage tank. a number of electrical signal detectors corresponding to the number of electrical signal detectors, and a decoder connected to the electrical signal detectors;
By including the decoder and the arithmetic unit connected to the electric signal detector, and the level indicator connected to the arithmetic unit, the level can be maintained even if the dielectric constant of the fluid stored in the storage tank changes. The purpose is to make it possible to accurately indicate the level on the display meter.

本発明の一実施例を第2図により説明する。 An embodiment of the present invention will be explained with reference to FIG.

第2図では、本発明によるレベル指示装置の構
成図で、なお、第2図で、第1図と同一装置等は
同一符号で示し説明を省略する。
FIG. 2 is a block diagram of a level indicating device according to the present invention. In FIG. 2, the same devices as those in FIG.

サポート11内には、電極12a〜12cが相
隣る電極と電気絶縁状態を保持して内接されてい
る。電極12a〜12cは、高周波電源13に接
続されている。レベル表示装置は、電極12a〜
12cの個数に見合う台数、この場合は、3台の
検出器14a〜14cと、検出器14a〜14c
と増幅器17を介し接続されたデコーダ18と、
デコーダ18並びに増幅器17を介し検出器14
a〜14cと接続された演算器19と、演算器1
9と接続されたレベル表示計20とで構成されて
いる。検出器14a〜14cは、抵抗15a〜1
5c、インダクタンス16a〜16cを介し高周
波電源13に接続され、かつ、貯槽10の外壁に
接続されている。
Electrodes 12a to 12c are inscribed within the support 11 while being electrically insulated from adjacent electrodes. The electrodes 12a to 12c are connected to a high frequency power source 13. The level display device includes electrodes 12a~
The number of detectors corresponding to the number of detectors 12c, in this case, three detectors 14a to 14c, and detectors 14a to 14c
and a decoder 18 connected via an amplifier 17,
Detector 14 via decoder 18 and amplifier 17
Arithmetic unit 19 connected to a to 14c, and arithmetic unit 1
9 and a level indicator 20 connected thereto. The detectors 14a to 14c have resistors 15a to 1
5c, is connected to the high frequency power source 13 via inductances 16a to 16c, and is also connected to the outer wall of the storage tank 10.

なお、高周波電源13の周波数およびインダク
タンス16a〜16cの容量を、貯槽10内の温
度、圧力、流体の組成等が変化し流体の誘電率変
化による静電容量の変動があつても検出器14a
〜14cで検出された電気信号変化、例えば、電
流値変化が最大値を超えないで、かつ、静電容量
と電流値との間が一次関数である範囲に設定す
る。
Note that the frequency of the high-frequency power source 13 and the capacitance of the inductances 16a to 16c are determined by the detector 14a even if the temperature, pressure, composition of the fluid, etc. in the storage tank 10 change, and the capacitance changes due to changes in the dielectric constant of the fluid.
- Set to a range in which the electrical signal change detected in step 14c, for example, the current value change, does not exceed the maximum value and in which the capacitance and the current value are a linear function.

貯槽10内に流体が第2図に示すレベルの位置
(l0)で貯蔵されているとすれば、この場合、流
体のレベルの位置(l0)は、次のようにして指示
される。
If fluid is stored in the reservoir 10 at the level position (l 0 ) shown in FIG. 2, then the level position (l 0 ) of the fluid is indicated as follows.

まず、高周波電源13を作動し、電極12a〜
12cと貯槽10間の静電容量より検出器14a
〜14cで電流値を検出する。この場合、検出器
14a〜14cで検出される電流値は第3図に示
すように、検出器14aではHighレベル、検出
器14bではLowレベルとHighレベルとの間、
検出器14cではLowレベルにあり、また、貯
槽10底壁と電極12a〜12cとの距離は予め
解つているため、デコーダ18より演算器19に
デジタル信号を出力し、演算器19で演算処理し
た後に演算器19よりレベル表示計20にデジタ
ル信号又はアナログ信号を出力することで、流体
のレベル(l0)は概略指示できる。また、流体の
レベル(l0)は、次のようにして正確に指示され
る。
First, the high frequency power supply 13 is activated, and the electrodes 12a~
Detector 14a from the capacitance between 12c and storage tank 10
The current value is detected at ~14c. In this case, as shown in FIG. 3, the current values detected by the detectors 14a to 14c are between the High level in the detector 14a and the Low level and the High level in the detector 14b.
Since the detector 14c is at a low level and the distance between the bottom wall of the storage tank 10 and the electrodes 12a to 12c is known in advance, the decoder 18 outputs a digital signal to the calculator 19, and the calculator 19 processes the digital signal. By later outputting a digital signal or an analog signal from the calculator 19 to the level indicator 20, the fluid level (l 0 ) can be roughly indicated. Also, the fluid level (l 0 ) is accurately indicated as follows.

検出器14bで検出された電流値(Id)を、検
出器14bより増幅器17を介して演算器19に
出力する。その後、演算器19では、次式に示す
演算式により流体レベル(l0)が演算処理され
る。この結果は、デジタル信号又はアナログ信号
でレベル表示計20に出力され、ここで、流体レ
ベル(l0)が正確に指示される。
The current value (I d ) detected by the detector 14b is output from the detector 14b to the arithmetic unit 19 via the amplifier 17. Thereafter, the computing unit 19 computes the fluid level (l 0 ) using the following equation. This result is output as a digital or analog signal to the level indicator 20, where the fluid level (l 0 ) is accurately indicated.

l0=l2+Id−Ie/Ih−Ie×Rp ここに、 l0:流体のレベル I2:貯槽底壁と電極12b下端との距離 Id:検出電流値 Ih:検出器14bでの電流値Highレベル Ie:検出器14bでの電流値Lowレベル Rp:電極12bの長さ 本実施例のようなレベル指示装置では、貯槽内
に貯蔵されている流体の導電率が変化しても、検
出器で検出される電流値、貯槽底壁から電極下端
までの距離並びに電極長さにより演算器で演算処
理しレベル表示計に出力することで流体のレベル
を正確に指示できる。
l 0 = l 2 + I d − I e / I hI e × R p where, l 0 : Fluid level I 2 : Distance between the bottom wall of the storage tank and the lower end of the electrode 12b I d : Detected current value I h : Current value High level Ie at the detector 14b: Current value Low level Rp at the detector 14b: Length of the electrode 12b In the level indicating device like this embodiment, the conductivity of the fluid stored in the storage tank is Even if the rate changes, the fluid level can be accurately determined by processing the current value detected by the detector, the distance from the bottom wall of the storage tank to the lower end of the electrode, and the length of the electrode using a calculator and outputting it to the level indicator. Can give instructions.

本発明によれば貯槽内に貯蔵されている流体の
レベルを演算処理し指示できるので、流体の誘電
率が変化してもレベル表示計でのレベル指示を正
確に行える効果がある。
According to the present invention, since the level of the fluid stored in the storage tank can be calculated and indicated, the level indicator can accurately indicate the level even if the dielectric constant of the fluid changes.

【図面の簡単な説明】[Brief explanation of drawings]

第1図は、従来のレベル指示装置の構成図、第
2図は、本発明によるレベル指示装置の一実施例
を示す構成図、第3図は、流体のレベルの位置と
検出器の電流値との関係線図である。 10……貯槽、11……サポート、12aから
12c……電極、13……高周波電源、14aか
ら14c……検出器、15aから15c……抵
抗、16aから16c……インダクタンス、17
……増幅器、18……デコーダ、19……演算
器、20……レベル表示計。
Fig. 1 is a block diagram of a conventional level indicating device, Fig. 2 is a block diagram showing an embodiment of the level indicating device according to the present invention, and Fig. 3 is a diagram showing the position of the fluid level and the current value of the detector. FIG. 10...Storage tank, 11...Support, 12a to 12c...Electrode, 13...High frequency power supply, 14a to 14c...Detector, 15a to 15c...Resistance, 16a to 16c...Inductance, 17
...Amplifier, 18...Decoder, 19...Arithmetic unit, 20...Level display meter.

Claims (1)

【特許請求の範囲】[Claims] 1 流体非浸透性並びに電気絶縁性を有する材料
で形成され貯槽内に垂設されたサポートと、該サ
ポート内に相隣る高周波電極と電気絶縁状態を保
持し前記サポートの長手方向に複数個配置された
高周波電極と、該高周波電極がそれぞれ接続され
た高周波電源と、抵抗並びにインダクタンスを介
し前記高周波電源にそれぞれ接続され、かつ、前
記貯槽にそれぞれ接続された前記高周波電極の個
数に見合う台数の電気信号検出器と、該電気信号
検出器と接続されたデコーダと、該デコーダ並び
に前記電気信号検出器と接続された演算器と、該
演算器と接続されたレベル表示計とを具備したこ
とを特徴とするレベル指示装置。
1. A support formed of a fluid-impermeable and electrically insulating material and vertically installed in a storage tank, and a plurality of supports arranged in the longitudinal direction of the support to maintain an electrically insulated state from adjacent high-frequency electrodes within the support. a high-frequency electrode connected to the high-frequency electrode, a high-frequency power source to which the high-frequency electrode is connected, and a number of electric devices connected to the high-frequency power source through resistance and inductance, and corresponding to the number of high-frequency electrodes connected to the storage tank. A signal detector, a decoder connected to the electric signal detector, an arithmetic unit connected to the decoder and the electric signal detector, and a level indicator connected to the arithmetic unit. level indicating device.
JP57068679A 1982-04-26 1982-04-26 Level indicating device Granted JPS58186017A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP57068679A JPS58186017A (en) 1982-04-26 1982-04-26 Level indicating device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP57068679A JPS58186017A (en) 1982-04-26 1982-04-26 Level indicating device

Publications (2)

Publication Number Publication Date
JPS58186017A JPS58186017A (en) 1983-10-29
JPH0236170B2 true JPH0236170B2 (en) 1990-08-15

Family

ID=13380643

Family Applications (1)

Application Number Title Priority Date Filing Date
JP57068679A Granted JPS58186017A (en) 1982-04-26 1982-04-26 Level indicating device

Country Status (1)

Country Link
JP (1) JPS58186017A (en)

Families Citing this family (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS60192226A (en) * 1984-03-14 1985-09-30 Tokyo Tatsuno Co Ltd Electrostatic capacity type level gauge
JPH02102443A (en) * 1988-10-07 1990-04-16 C L Keisoku Kogyo Kk Boundary surface detector
JP2003291367A (en) * 2002-04-02 2003-10-14 Sony Corp Device for displaying remaining amount of liquid

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5410261A (en) * 1977-06-24 1979-01-25 Tateyama Aluminum Kogyo Kk Method and apparatus for molding helecal shaped member

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS5410261A (en) * 1977-06-24 1979-01-25 Tateyama Aluminum Kogyo Kk Method and apparatus for molding helecal shaped member

Also Published As

Publication number Publication date
JPS58186017A (en) 1983-10-29

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