JPH0618316A - Liquid level measuring device - Google Patents
Liquid level measuring deviceInfo
- Publication number
- JPH0618316A JPH0618316A JP19904092A JP19904092A JPH0618316A JP H0618316 A JPH0618316 A JP H0618316A JP 19904092 A JP19904092 A JP 19904092A JP 19904092 A JP19904092 A JP 19904092A JP H0618316 A JPH0618316 A JP H0618316A
- Authority
- JP
- Japan
- Prior art keywords
- reflector
- liquid level
- liquid surface
- reference distance
- distance
- 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.)
- Pending
Links
Landscapes
- Level Indicators Using A Float (AREA)
Abstract
(57)【要約】
【目的】 液面上に充満している気体の濃度に影響され
ることなく液面までの距離を正確に測定できる様にする
こと。
【構成】 液面４の上方に位置した送受波器１から液面
４に向かって超音波パルスを発射し、超音波パルスの伝
播時間によって送受波器から液面４までの距離を測定す
る液面位置計測装置において、送受波器１直下の液面４
上に浮子式反射器８を浮かべ、この浮子式反射器８の上
面に基準距離反射器７を取付けると共に送受波器１の下
面にも基準距離反射器６を取付ける。
(57) [Summary] [Purpose] To enable accurate measurement of the distance to the liquid surface without being affected by the concentration of the gas filling the liquid surface. [Structure] A liquid that emits an ultrasonic pulse toward a liquid surface 4 from a transducer 1 located above the liquid surface 4 and measures the distance from the transducer to the liquid surface 4 according to the propagation time of the ultrasonic pulse. In the surface position measuring device, the liquid level 4 immediately below the transducer 1
The float type reflector 8 is floated on the upper surface, the reference distance reflector 7 is attached to the upper surface of the float type reflector 8, and the reference distance reflector 6 is also attached to the lower surface of the transducer 1.
Description
【０００１】[0001]
【産業上の利用分野】この発明は液面位置計測装置、詳
しくは超音波を利用して液面までの距離を無接触で正確
に計測することができる液面位置計測装置に関するもの
である。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid surface position measuring device, and more particularly to a liquid surface position measuring device capable of accurately measuring a distance to a liquid surface by utilizing ultrasonic waves without contact.
【０００２】[0002]
【従来の技術】図２は従来の代表的な液面位置計測装置
の概念図である。図中１は送受波器、２は送受信器、３
は表示器、４は液面、５は底面であり、送受波器１は液
面４から一定の距離をへだてて、その上方に位置せしめ
られており、送受波器１から液面４に向かって発射した
超音波パルスが液面４で反射して送受波器１に戻ってく
る時間（伝播時間）から液面位置を測定する様になって
いた。2. Description of the Related Art FIG. 2 is a conceptual view of a typical conventional liquid surface position measuring device. In the figure, 1 is a transceiver, 2 is a transceiver, and 3
Is a display device, 4 is a liquid surface, and 5 is a bottom surface. The wave transmitter / receiver 1 is located at a certain distance above the liquid surface 4 and is positioned above the wave receiver / transmitter 1 toward the liquid surface 4. The position of the liquid surface is measured from the time (propagation time) in which the ultrasonic pulse emitted by the ultrasonic wave is reflected by the liquid surface 4 and returned to the transducer 1.
【０００３】図３を参照しながらその動作を説明する
と、送受信器２において繰返しパルス（Ａ）を発生さ
せ、その立上り点において送信パルス（Ｂ）を発生し、
搬送パルス（Ｃ）を出力し、送受波器１に電気出力とし
て供給する。送受波器１はこの電気出力を機械振動−音
響と変換し、音波出力が液面４に向かって発射される。The operation will be described with reference to FIG. 3. In the transmitter / receiver 2, a repetitive pulse (A) is generated and a transmission pulse (B) is generated at its rising point.
The carrier pulse (C) is output and supplied to the wave transceiver 1 as an electric output. The transducer 1 converts this electric output into mechanical vibration-sound, and the sound wave output is emitted toward the liquid surface 4.
【０００４】発射された音波は液面４で反射され、再び
送受波器１に戻り、電気信号に可逆変換されて再び送受
信器２に入力され、受波信号（Ｄ）となる。この受波信
号（Ｄ）は増巾され、検波出力（Ｅ）からサンプリング
パルス６を発生し、伝播時間ｔが計測されている。又、
ＲＭＰ発生パルス（Ｇ）によりＲＭＰ信号（Ｈ）を発生
し、サンプリングパルス（Ｆ）によって時間／電圧変換
し、距離に比例した電圧（Ｉ）を発生し、表示器３に距
離出力される。The emitted sound wave is reflected by the liquid surface 4, returns to the wave transmitter / receiver 1 again, is reversibly converted into an electric signal, and is input again to the transmitter / receiver 2 to become a wave receiver signal (D). The received signal (D) is amplified, a sampling pulse 6 is generated from the detected output (E), and the propagation time t is measured. or,
The RMP signal (H) is generated by the RMP generation pulse (G), the time / voltage is converted by the sampling pulse (F), the voltage (I) proportional to the distance is generated, and the distance is output to the display device 3.
【０００５】これらの関係は、液面４までの距離をＬ
1 、伝播音速をＣ、伝播時間をｔとしたとき、The relationship between these is that the distance to the liquid level 4 is L
1 , the propagation sound velocity is C, and the propagation time is t,
【数１】 で示される。[Equation 1] Indicated by.
【０００６】[0006]
【発明が解決しようとする課題】しかし、一般には液面
４の上方には液体から蒸発した気体１０が充満してお
り、この気体１０の濃度が上下で異なる場合には超音波
の伝播速度（音速）が変化し、その変化分だけ、誤差が
生ずることは避けられなかった。つまり、伝播音速Ｃは
普遍ガス定数をＲ、分子量をＭ、密度をρ、気圧をｐ、
定圧比熱／定体比熱をγとした場合。However, in general, the gas 10 evaporated from the liquid is filled above the liquid surface 4, and when the concentration of the gas 10 is different between the upper and lower sides, the propagation velocity of the ultrasonic wave ( It was inevitable that the sound velocity would change, and an error would occur due to the change. That is, the propagation sound velocity C is the universal gas constant R, the molecular weight M, the density ρ, the atmospheric pressure p,
When constant pressure specific heat / constant body specific heat is γ.
【数２】 となり、Ｃは各種定数の変化に従って変化するので、条
件が一定でない場合には誤差が生じることになる。[Equation 2] Since C changes according to changes in various constants, an error will occur if the conditions are not constant.
【０００７】同様に、温度、湿度、圧力によっても音速
は影響を受けやすく、誤差発生の原因となっていた。な
お、温度については測温体による計測で一応補正可能で
あるが、どこの点で補正するかがかなりむずかしく、又
温度分布が一定でない場合には補正できない欠点もあっ
た。Similarly, the speed of sound is easily affected by temperature, humidity, and pressure, which causes an error. It should be noted that the temperature can be corrected once by measurement with a temperature sensing element, but it is quite difficult to determine at what point the temperature should be corrected, and there is a drawback that the temperature cannot be corrected if the temperature distribution is not constant.
【０００８】この発明は上記従来の問題点に鑑み発明さ
れたものであり、液面側の音速を測定することにより、
正確に平均音速を算出して音速補正を実施し、測定の高
精度化を図ると共に、液面ゆれに影響されない測定の安
定化を実現した液面位置測定装置を提供せんとするもの
である。The present invention has been invented in view of the above-mentioned conventional problems, and by measuring the sound velocity on the liquid surface side,
An object of the present invention is to provide a liquid surface position measuring device that accurately calculates an average sound velocity and corrects the sound velocity to improve the accuracy of the measurement and stabilize the measurement without being affected by the liquid surface fluctuation.
【０００９】[0009]
【課題を解決するための手段】この本発明は、液面４の
上方に位置した送受波器１から液面４に向かって超音波
パルスを発射し、超音波パルスの伝播時間によって送受
波器から液面４までの距離を測定する液面位置計測装置
において、送受波器１直下の液面４上に浮子式反射器８
を浮かべ、この浮子式反射器８の上面に基準距離反射器
７を取付けると共に送受波器１の下面にも基準距離反射
器６を取り付けて液面位置計測装置を構成することによ
り、上記課題を解決せんとするものである。According to the present invention, an ultrasonic wave pulse is emitted from a wave transmitter / receiver 1 located above a liquid level 4 toward a liquid level 4, and the wave transmitter / receiver is generated depending on the propagation time of the ultrasonic pulse. In the liquid surface position measuring device for measuring the distance from the liquid surface to the liquid surface 4, the float type reflector 8 is placed on the liquid surface 4 directly below the transducer 1.
The above problem is solved by mounting the reference distance reflector 7 on the upper surface of the float type reflector 8 and also by mounting the reference distance reflector 6 on the lower surface of the wave transmitter / receiver 1 to form a liquid level position measuring device. It is a solution.
【００１０】[0010]
【作用】送受信器２において発生された搬送パルス
（Ｃ）が送受波器１において音響信号に変換され、音波
出力として液面４に向かって発射される。液面４で発射
された音波は送受波器１に戻り、電気信号に可逆変換さ
れ、送受信器２において受波信号（Ｄ）となり、音波の
伝播時間ｔが計測される。The carrier pulse (C) generated in the transmitter / receiver 2 is converted into an acoustic signal in the wave transmitter / receiver 1 and is emitted toward the liquid surface 4 as a sound wave output. The sound wave emitted from the liquid level 4 returns to the wave transmitter / receiver 1 and is reversibly converted into an electric signal, and becomes a wave reception signal (D) in the transmitter / receiver 2, and the propagation time t of the sound wave is measured.
【００１１】この際、受波信号（Ｄ）には送受波器１側
の基準距離反射器６と液面４側の基準距離反射器７から
の受信波が出力されるので、送受波器１側の基準距離反
射６のサンプリングパルス（Ｊ）によりＲＭＰ発生パル
ス発生点（Ｇ）を制御し、液面４側の基準距離反射器７
のサンプリングパルスと浮子式反射器８のサンプリング
パルス（Ｋ）により基準距離時間を出力し、基準時間
（Ｍ）との伝播時間差（Ｎ）を出力し、この時間差信号
によりＲＭＰ電圧（Ｏ）の傾きを可変することにより、
音速変化分を補正し、距離の真値（Ｉ）を電圧出力とし
て出力表示する。At this time, since the received wave from the reference distance reflector 6 on the side of the wave transmitter / receiver 1 and the reference distance reflector 7 on the side of the liquid level 4 is output as the received wave signal (D), the wave transmitter / receiver 1 The RMP generation pulse generation point (G) is controlled by the sampling pulse (J) of the reference distance reflection 6 on the side, and the reference distance reflector 7 on the liquid level 4 side.
The reference distance time is output by the sampling pulse of (1) and the sampling pulse (K) of the floating reflector 8 and the propagation time difference (N) from the reference time (M) is output, and the slope of the RMP voltage (O) is output by this time difference signal. By changing
The change in sound velocity is corrected, and the true value (I) of the distance is output and displayed as a voltage output.
【００１２】[0012]
【実施例】図１はこの発明の一実施例の概念図であり、
図中１は送受波器、２は送受信器、３は表示器であり、
図２に示した従来例と同様に、送受波器１は液面４から
一定の距離をへだててその上方に位置せしめられてい
る。FIG. 1 is a conceptual diagram of an embodiment of the present invention,
In the figure, 1 is a transceiver, 2 is a transceiver, 3 is a display,
As in the conventional example shown in FIG. 2, the wave transmitter / receiver 1 is positioned above the liquid level 4 with a certain distance.
【００１３】そして、この送受波器１の下面には基準距
離反射器６が取付けられている。一方、送受波器１の直
下の液面４上には浮子式反射器８が浮かべられており、
この浮子式反射器８の上面には基準距離反射器７が取付
けられている。A reference distance reflector 6 is attached to the lower surface of the wave transmitter / receiver 1. On the other hand, the float type reflector 8 is floated on the liquid surface 4 just below the transducer 1.
The reference distance reflector 7 is attached to the upper surface of the float type reflector 8.
【００１４】基準距離反射器６の厚さをＬ1 、基準基準
距離反射器７の厚さをＬ4 、液面４から底面５までの距
離をＬ2 、基準距離反射器６の下面から基準基準距離反
射器７の上面までの距離をＬ3 、送受波器１の下面から
底面５までの距離をＬとした場合、 Ｌ＝（Ｌ1 ＋Ｌ3 ＋Ｌ4 ）＋Ｌ2 ∴Ｌ2 ＝Ｌ−（Ｌ1 ＋Ｌ3 ＋Ｌ4 ）となっている。The thickness of the reference distance reflector 6 is L 1 , the thickness of the reference reference distance reflector 7 is L 4 , the distance from the liquid surface 4 to the bottom surface 5 is L 2 , and the bottom of the reference distance reflector 6 is the reference. L = (L 1 + L 3 + L 4 ) + L 2 ∴L 2 = L−, where L 3 is the distance to the upper surface of the reference distance reflector 7 and L is the distance from the lower surface of the transducer 1 to the bottom surface 5. (L 1 + L 3 + L 4 ).
【００１５】又、前記浮子式反射器８と底面５とは接地
線９によって接続されている。これは構造物と同一電位
にし、静電気等の発生の阻止を図る安全性確保の為であ
る。The floating reflector 8 and the bottom surface 5 are connected by a ground wire 9. This is to ensure safety by keeping the same potential as the structure and preventing the generation of static electricity.
【００１６】次に、図４を参照しながらその動作を説明
すると、送受信器２において繰返しパルス（Ａ）を発生
させ、その立上がり点において送信パルス（Ｂ）を発
し、これに基づき搬送パルス（Ｃ）を送受波器１に出力
する。この搬送パルス（Ｃ）は送受波器１において電気
−機械振動−音響に変換されて超音波信号となり、液面
４に向かって発射される。液面４で反射された超音波信
号は再び送受波器１に戻り、音響−機械信号−電気信号
に可逆変換され、再び送受信器２に入力され受信出力
（Ｄ）となる。Next, the operation will be described with reference to FIG. 4. In the transmitter / receiver 2, a repetitive pulse (A) is generated, a transmission pulse (B) is emitted at the rising point thereof, and based on this, a carrier pulse (C) is generated. ) Is output to the transceiver 1. The carrier pulse (C) is converted into an electro-mechanical vibration-acoustic sound in the wave transmitter / receiver 1 to become an ultrasonic signal, which is emitted toward the liquid surface 4. The ultrasonic signal reflected by the liquid surface 4 returns to the wave transmitter / receiver 1 again, is reversibly converted into an acoustic-mechanical signal-electric signal, and is input again to the transmitter / receiver 2 to become a reception output (D).
【００１７】送受波器１の下部には基準距離反射器６
が、液面４上には基準距離反射器７がそれぞれ位置して
おり、受信出力（Ｄ）には基準距離反射器６からの受信
波及び基準距離反射器７からの受信波がそれぞれ出力さ
れるので、送受波器側の基準距離反射器６のサンプリン
グパルス（Ｊ）によりＲＭＰ発生パルス（Ｇ）の発生点
を制御する。又、液面４側の基準距離反射器７のサンプ
リングパルスと浮子サンプリングパルス（Ｋ）により基
準距離時間（Ｌ）を出力し、基準時間（Ｍ）との伝播時
間差（Ｎ）を出力し、この時間差信号によりＲＭＰ電圧
（Ｏ）の傾きを可変し、音速変化分を補正し、距離の真
値を電圧出力（Ｉ）として出力表示する。Below the transmitter / receiver 1, a reference distance reflector 6 is provided.
However, the reference distance reflectors 7 are respectively located on the liquid surface 4, and the reception wave from the reference distance reflector 6 and the reception wave from the reference distance reflector 7 are output to the reception output (D). Therefore, the generation point of the RMP generation pulse (G) is controlled by the sampling pulse (J) of the reference distance reflector 6 on the transmitter / receiver side. Further, the reference distance time (L) is output by the sampling pulse of the reference distance reflector 7 on the liquid level 4 side and the float sampling pulse (K), and the propagation time difference (N) from the reference time (M) is output. The slope of the RMP voltage (O) is changed by the time difference signal, the change in sound velocity is corrected, and the true value of the distance is output and displayed as the voltage output (I).
【００１８】[0018]
【発明の効果】上記構成により、気体１０の濃度、圧
力、温度等の分布が異っていても、上下一対の基準距離
反射器６，７により上下の音速を計測し、精度の高い定
性化した平均音速を算出できるようになっている。With the above structure, even if the distribution of the concentration, pressure, temperature, etc. of the gas 10 is different, the upper and lower sound velocities are measured by the pair of upper and lower reference distance reflectors 7 and qualitized with high accuracy. The average sound velocity can be calculated.
【００１９】この様に、常に基準距離と対比する計測法
であり、変化分を音速補正できるので測定の高精度化が
図られ、又位相合成による変動や液面のゆれを浮子によ
って制圧できるので、測定の安定化も図ることができ、
極めて高い実用性を有するものである。As described above, the measurement method is always contrasted with the reference distance, and the variation can be corrected by the sound velocity, so that the measurement accuracy can be improved, and the fluctuation due to the phase composition and the fluctuation of the liquid surface can be suppressed by the float. , Can stabilize the measurement,
It has extremely high practicality.
【００２０】[0020]
【図１】この発明に係る液面位置計測装置の一実施例の
概念図である。FIG. 1 is a conceptual diagram of an embodiment of a liquid surface position measuring device according to the present invention.
【図２】従来例の一例の概念図である。FIG. 2 is a conceptual diagram of an example of a conventional example.
【図３】従来例における各信号のタイムチャートであ
る。FIG. 3 is a time chart of each signal in the conventional example.
【図４】この発明の実施例において発生する各信号のタ
イムチャートである。FIG. 4 is a time chart of each signal generated in the embodiment of the present invention.
１ 送受波器 ２ 送受信器 ３ 表示器 ４ 液面 ５ 底面 ６ 基準距離反射器 ７ 基準距離反射器 ８ 浮子式反射器 ９ 接地線 １０ 気体 1 Transducer 2 Transceiver 3 Display 4 Liquid level 5 Bottom 6 Reference distance reflector 7 Reference distance reflector 8 Float reflector 9 Ground wire 10 Gas
Claims (1)
液面４に向かって超音波パルスを発射し、超音波パルス
の伝播時間によって送受波器から液面４までの距離を測
定する液面位置計測装置において、送受波器１直下の液
面４上に浮子式反射器８を浮かべ、この浮子式反射器８
の上面に基準距離反射器７を取付けると共に送受波器１
の下面にも基準距離反射器６を取付けたことを特徴とす
る液面位置計測装置。1. A ultrasonic wave pulse is emitted from a transducer 1 positioned above the liquid level 4 toward the liquid level 4, and the distance from the transducer to the liquid level 4 is measured by the propagation time of the ultrasonic pulse. In the liquid level position measuring device, the float type reflector 8 is floated on the liquid level 4 directly below the wave transmitter / receiver 1.
The reference distance reflector 7 is attached to the upper surface of the
A liquid level position measuring device characterized in that a reference distance reflector 6 is also attached to the lower surface of the.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19904092A JPH0618316A (en) | 1992-07-03 | 1992-07-03 | Liquid level measuring device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP19904092A JPH0618316A (en) | 1992-07-03 | 1992-07-03 | Liquid level measuring device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH0618316A true JPH0618316A (en) | 1994-01-25 |
Family
ID=16401121
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP19904092A Pending JPH0618316A (en) | 1992-07-03 | 1992-07-03 | Liquid level measuring device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0618316A (en) |
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|---|---|---|---|---|
| DE102004036645A1 (en) * | 2004-07-28 | 2006-02-16 | Landis+Gyr Gmbh | Ultrasonic level sensor device |
| KR20150140952A (en) * | 2014-06-09 | 2015-12-17 | 주식회사 대유위니아 | Electrostatic capacitance type device for detecting liquid level |
| CN105424139B (en) * | 2015-11-05 | 2018-08-28 | 河海大学 | Level of ground water plugging meter devices and methods therefor based on ultrasonic wave negative pressure |
| DE102019207892A1 (en) * | 2019-05-29 | 2020-12-03 | Pepperl+Fuchs Gmbh | Level measuring device and method for measuring a level |
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| CN115597686A (en) * | 2022-11-21 | 2023-01-13 | 安徽新建控股集团有限公司（Cn） | Device and method for measuring and separating oil layer depth after oily sewage standing and layering |
| CN117848458A (en) * | 2024-03-06 | 2024-04-09 | 潍坊远邦人工智能研发有限公司 | Liquid level measurement device based on singlechip |
-
1992
- 1992-07-03 JP JP19904092A patent/JPH0618316A/en active Pending
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE102004036645A1 (en) * | 2004-07-28 | 2006-02-16 | Landis+Gyr Gmbh | Ultrasonic level sensor device |
| KR20150140952A (en) * | 2014-06-09 | 2015-12-17 | 주식회사 대유위니아 | Electrostatic capacitance type device for detecting liquid level |
| CN105424139B (en) * | 2015-11-05 | 2018-08-28 | 河海大学 | Level of ground water plugging meter devices and methods therefor based on ultrasonic wave negative pressure |
| DE102019207892A1 (en) * | 2019-05-29 | 2020-12-03 | Pepperl+Fuchs Gmbh | Level measuring device and method for measuring a level |
| CN115597686A (en) * | 2022-11-21 | 2023-01-13 | 安徽新建控股集团有限公司（Cn） | Device and method for measuring and separating oil layer depth after oily sewage standing and layering |
| CN115540976A (en) * | 2022-11-24 | 2022-12-30 | 安徽新建控股集团有限公司 | Orientation measurement device based on buoyancy and orientation measurement method thereof |
| CN117848458A (en) * | 2024-03-06 | 2024-04-09 | 潍坊远邦人工智能研发有限公司 | Liquid level measurement device based on singlechip |
| CN117848458B (en) * | 2024-03-06 | 2024-05-31 | 潍坊远邦人工智能研发有限公司 | Liquid level measurement device based on singlechip |
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