JPS6351253B2 - - Google Patents
Info
- Publication number
- JPS6351253B2 JPS6351253B2 JP55069241A JP6924180A JPS6351253B2 JP S6351253 B2 JPS6351253 B2 JP S6351253B2 JP 55069241 A JP55069241 A JP 55069241A JP 6924180 A JP6924180 A JP 6924180A JP S6351253 B2 JPS6351253 B2 JP S6351253B2
- Authority
- JP
- Japan
- Prior art keywords
- liquid helium
- superconducting wire
- liquid
- helium
- level
- 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
Links
- 239000007788 liquid Substances 0.000 claims description 50
- 239000001307 helium Substances 0.000 claims description 38
- 229910052734 helium Inorganic materials 0.000 claims description 38
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 38
- 238000009413 insulation Methods 0.000 claims description 5
- SWQJXJOGLNCZEY-BJUDXGSMSA-N helium-3 atom Chemical compound [3He] SWQJXJOGLNCZEY-BJUDXGSMSA-N 0.000 description 11
- 238000009835 boiling Methods 0.000 description 2
- 238000001704 evaporation Methods 0.000 description 2
- 230000008020 evaporation Effects 0.000 description 2
- 238000005259 measurement Methods 0.000 description 2
- 229920002799 BoPET Polymers 0.000 description 1
- 239000005041 Mylar™ Substances 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 238000000576 coating method Methods 0.000 description 1
- 210000003298 dental enamel Anatomy 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 239000007789 gas Substances 0.000 description 1
- 238000000691 measurement method Methods 0.000 description 1
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
- G01F23/24—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 resistance of resistors due to contact with conductor fluid
Landscapes
- Physics & Mathematics (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】
この発明は、液体ヘリウム液面計に関し、とく
に精度の向上をはかつた液体ヘリウム液面計に関
するものである。DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a liquid helium level gauge, and more particularly to a liquid helium level gauge with improved accuracy.
従来の液体ヘリウム液面計の構成を図に示す。
この図において、１は裸の超電導線、２は液体ヘ
リウム槽、３は液体ヘリウム、４は直流定電流電
源、５は電圧計である。 The configuration of a conventional liquid helium level gauge is shown in the figure.
In this figure, 1 is a bare superconducting wire, 2 is a liquid helium tank, 3 is liquid helium, 4 is a DC constant current power source, and 5 is a voltmeter.
次に、図に示す液体ヘリウム計の動作について
説明する。超電導線の臨界温度は液体ヘリウムの
温度よりも若干高い。すなわち、超電導線１のう
ちで液体ヘリウム３中に浸つている部分は超電導
状態であり、その抵抗は零である。一方、超電導
線１のうちで液体ヘリウム３外に出ており、液体
ヘリウムに直接触れていない部分の温度は、超電
導線１の臨界温度よりも通常高くなつている。こ
のために、液体ヘリウム３外に出ている超電導線
１の部分は常電導状態であり、抵抗を有する。こ
の性質を利用して、液体ヘリウムの液面を測定で
きる。この測定方法を具体的に説明する。超電導
線１の直流定電流電源４により定電流を流してお
く、超電導線１の両端の電圧を測定する。この電
圧をＶとする。この時の液体ヘリウム３の液面高
さ（超電導線の下端からの高さ）は次式で与えら
れる。 Next, the operation of the liquid helium meter shown in the figure will be explained. The critical temperature of superconducting wire is slightly higher than that of liquid helium. That is, the portion of the superconducting wire 1 immersed in the liquid helium 3 is in a superconducting state, and its resistance is zero. On the other hand, the temperature of the portion of the superconducting wire 1 that is out of the liquid helium 3 and not in direct contact with the liquid helium is usually higher than the critical temperature of the superconducting wire 1. For this reason, the portion of the superconducting wire 1 that is exposed to the outside of the liquid helium 3 is in a normal conductive state and has resistance. This property can be used to measure the level of liquid helium. This measurement method will be specifically explained. A constant current is passed through the superconducting wire 1 by a direct current constant current power source 4, and the voltage across the superconducting wire 1 is measured. Let this voltage be V. The liquid level height of the liquid helium 3 at this time (height from the lower end of the superconducting wire) is given by the following equation.
ｌ＝l0（１−Ｖ／V0）
ただし、l0＝超電導線の長さ（電圧測定部分）
V0＝超電導線の液体ヘリウムに浸つていない
時の超電導線の両端の電圧
次に、この液体ヘリウム計の精度について考え
てみる。この液面計の精度は、超電導線１の超電
導部分と常電導部分の境界面が液体ヘリウムの液
面とどの程度ずれるかによつて決まる。液体ヘリ
ウムの蒸発量が充分に小さい場合には、一般に前
述のずれはほとんどなく、この液面計で精度よく
液体ヘリウム３の液面を測定することができる。
通常、液体ヘリウム槽２中には超電導コイルなど
の極低温装置が設置される。この場合、前記極低
温装置の支持部材、電流リード線などを通して液
体ヘリウム３の蒸発量は比較的多いのが通常であ
る。そして、液体ヘリウムの蒸発量が比較的多い
と、超電導線１の液体ヘリウム３から外に出てい
る部分のうち、その液面に近い部分は、液体ヘリ
ウムの蒸発ガスにより十分に冷却されて超電導状
態になつてしまう。このために、超電導線１の両
端の電圧が液体ヘリウムの真の液面の値よりも小
さくなり、液面が実際よりも高く測定される。す
なわち、以上のように構成された従来の液体ヘリ
ウム計は、液面が実際よりも高く測定される欠点
があつた。 l=l 0 (1-V/V 0 ) However, l 0 = Length of the superconducting wire (voltage measurement part) V 0 = Voltage at both ends of the superconducting wire when it is not immersed in liquid helium Next Let's consider the accuracy of this liquid helium meter. The accuracy of this liquid level gauge is determined by how much the interface between the superconducting portion and the normal conducting portion of the superconducting wire 1 deviates from the liquid helium level. When the amount of evaporation of liquid helium is sufficiently small, there is generally almost no deviation as described above, and the level of liquid helium 3 can be measured with high precision using this level meter.
Usually, a cryogenic device such as a superconducting coil is installed in the liquid helium tank 2. In this case, the amount of liquid helium 3 that evaporates through the support members, current lead wires, etc. of the cryogenic device is usually relatively large. When the amount of evaporation of liquid helium is relatively large, the part of the superconducting wire 1 that is close to the liquid surface out of the liquid helium 3 is sufficiently cooled by the evaporated gas of the liquid helium, and becomes superconducting. It becomes a state. For this reason, the voltage across the superconducting wire 1 becomes smaller than the true level of liquid helium, and the liquid level is measured to be higher than it actually is. That is, the conventional liquid helium meter configured as described above has the disadvantage that the liquid level is measured higher than the actual level.
この発明は、前述のような従来の欠点を除去す
るためになされたもので、超電導線の熱絶縁皮膜
で被覆することにより、液体ヘリウムの液面を精
度よく測定できる液体ヘリウム液面計を提供する
ことを目的とするものである。 This invention was made in order to eliminate the above-mentioned drawbacks of the conventional technology, and provides a liquid helium level meter that can accurately measure the level of liquid helium by coating a superconducting wire with a thermally insulating film. The purpose is to
以下、この発明の一実施例について説明する。
超電導線１の表面を熱絶縁皮膜で覆う。具体的に
は、エナメル被覆を施し、あるいはマイラーなど
の薄いテープを巻回などする。 An embodiment of the present invention will be described below.
The surface of the superconducting wire 1 is covered with a thermal insulation film. Specifically, it is coated with enamel or wrapped with thin tape such as Mylar.
上記のように構成された超電導線１を有する液
体ヘリウム液面計において、超電導線１のうち、
液体ヘリウム３の液面から外に出ている気体ヘリ
ウム中の常電導部分の発熱は、熱絶縁皮膜の表面
から気体ヘリウムによつて奪われる。このとき、
気体ヘリウムの熱伝達は、液体ヘリウムの沸騰熱
伝達に比べ、十分に小さいため熱絶縁皮膜には厚
さ方向に温度勾配が生じ、ヘリウム液面から突出
する超電導線１の常電導部分の温度は、その周り
の気体ヘリウムの温度より高くなる。 In the liquid helium level gauge having the superconducting wire 1 configured as described above, the superconducting wire 1 includes:
The heat generated by the normally conductive portion of the gaseous helium that is coming out from the surface of the liquid helium 3 is removed by the gaseous helium from the surface of the heat insulating film. At this time,
Since the heat transfer of gaseous helium is sufficiently smaller than the boiling heat transfer of liquid helium, a temperature gradient occurs in the thickness direction of the thermal insulation film, and the temperature of the normal conducting part of the superconducting wire 1 protruding from the helium liquid surface is , becomes higher than the temperature of the surrounding gaseous helium.
一方、液体ヘリウム３中の超電導線１の温度
は、液体ヘリウムの沸騰熱伝達が大きいため、熱
絶縁皮膜があつても液体ヘリウムの温度と殆ど同
一となる。従つて、液体ヘリウム３の蒸発が激し
く、液面上部の気体ヘリウムと液体間に温度勾配
があまり生じない状態であつても、液体ヘリウム
３の液面を境界にして、超電導線１が常電導部分
と超電導部分に明確に分かれ、これによつて精度
よく液体ヘリウムの液面を測定することができ
る。 On the other hand, the temperature of the superconducting wire 1 in the liquid helium 3 is almost the same as the temperature of the liquid helium even if there is a thermal insulation film because the boiling heat transfer of the liquid helium is large. Therefore, even if the liquid helium 3 evaporates rapidly and there is not much temperature gradient between the gaseous helium above the liquid level and the liquid, the superconducting wire 1 becomes normal conductive with the liquid helium 3 level as the boundary. The liquid helium level can be measured with high accuracy.
なお、この発明において、前述した以外は図に
示し、既述した従来のものと同様であるから説明
を省略する。 In addition, in this invention, the parts other than those described above are shown in the drawings and are the same as the conventional ones described above, so the explanation will be omitted.
以上説明したように、この発明によれば超電導
線の表面を、その常電導部分の温度を気体ヘリウ
ム温度より高くなるよう保持するための熱絶縁皮
膜で覆つたので、気体ヘリウム雰囲気温度が液体
ヘリウム温度と殆ど同一であつても、これに左右
されることなく常に精度の高い測定ができるとい
う効果がある。 As explained above, according to the present invention, the surface of the superconducting wire is covered with a thermal insulation film to maintain the temperature of the normal conducting part higher than the gaseous helium temperature. The effect is that even if the temperature is almost the same, highly accurate measurements can always be made regardless of the temperature.
図は液体ヘリウム液面計の一例を示す構成説明
図である。
１……超電導線、２……液体ヘリウム槽、３…
…液体ヘリウム、４……直流定電流電源、５……
電圧計。
The figure is a configuration explanatory diagram showing an example of a liquid helium level gauge. 1...Superconducting wire, 2...Liquid helium tank, 3...
...Liquid helium, 4...DC constant current power supply, 5...
voltmeter.
Claims (1)
超電導部分と常電導部分を生じさせる超電導線を
用いた液体ヘリウム液面計において、上記超電導
線の表面を、その常電導部分の温度を気体ヘリウ
ム温度より高くなるよう保持するための熱絶縁皮
膜で覆つたことを特徴とする液体ヘリウム液面
計。1. In a liquid helium level gauge using a superconducting wire that generates a superconducting part and a normal conducting part by placing it in a helium liquid or air, the surface of the superconducting wire is A liquid helium level gauge characterized by being covered with a thermal insulation film to maintain the level higher than the temperature.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6924180A JPS56164924A (en) | 1980-05-23 | 1980-05-23 | Liquid helium level gage |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP6924180A JPS56164924A (en) | 1980-05-23 | 1980-05-23 | Liquid helium level gage |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS56164924A JPS56164924A (en) | 1981-12-18 |
| JPS6351253B2 true JPS6351253B2 (en) | 1988-10-13 |
Family
ID=13397053
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP6924180A Granted JPS56164924A (en) | 1980-05-23 | 1980-05-23 | Liquid helium level gage |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS56164924A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0353164A (en) * | 1989-07-20 | 1991-03-07 | Canon Inc | Sample supply device and sample measuring instrument using the same |
| CN110095523A (en) * | 2018-01-29 | 2019-08-06 | 宝山钢铁股份有限公司 | A method of the prediction quick-fried occurrence probability size of enamelware squama |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS60111926A (en) * | 1983-11-22 | 1985-06-18 | Aisin Seiki Co Ltd | Liquid helium liquid-level meter |
| JPS61175526A (en) * | 1985-01-29 | 1986-08-07 | Aisin Seiki Co Ltd | Liquid helium level meter |
| US5114907A (en) * | 1991-03-15 | 1992-05-19 | Illinois Superconductor Corporation | Cryogenic fluid level sensor |
| US5593949A (en) * | 1993-07-06 | 1997-01-14 | Lockheed Martin Corporation | High temperature conductor probes for determining liquid level of cryogens |
| US10486850B1 (en) | 2018-05-11 | 2019-11-26 | The Procter & Gamble Company | Hinged click to close container |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5334743A (en) * | 1976-09-09 | 1978-03-31 | Kyowa Hakko Kogyo Co Ltd | Preparation of 2-(4-alkylphenyl)propionic acids |
-
1980
- 1980-05-23 JP JP6924180A patent/JPS56164924A/en active Granted
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5334743A (en) * | 1976-09-09 | 1978-03-31 | Kyowa Hakko Kogyo Co Ltd | Preparation of 2-(4-alkylphenyl)propionic acids |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0353164A (en) * | 1989-07-20 | 1991-03-07 | Canon Inc | Sample supply device and sample measuring instrument using the same |
| CN110095523A (en) * | 2018-01-29 | 2019-08-06 | 宝山钢铁股份有限公司 | A method of the prediction quick-fried occurrence probability size of enamelware squama |
| CN110095523B (en) * | 2018-01-29 | 2021-05-14 | 宝山钢铁股份有限公司 | Method for predicting scale explosion occurrence probability of enamel product |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS56164924A (en) | 1981-12-18 |
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