JP2011214951A - Super-conductive liquid level meter - Google Patents
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Abstract
【課題】超伝導線材の機械的な脆弱性や熱への脆弱性を補うと共に、液体水素のように液位の検出が困難な低温液体であっても正確に液位を測定することができる超伝導液面計を提供する。
【解決手段】低温液体２に少なくとも一部が接触した状態で収納容器３内に立設する超伝導線材４と、超伝導線材４に電流を供給する電源７と、超伝導線材４の上端部に配設され電源７から供給された電流により熱を発生するヒータ８とを備え、超伝導線材４の両端部に、少なくとも超伝導線材４よりも加工度が大きい導電線を溶着して接続部を形成し、接続部と電源７とが電気的に接続された状態で、接続部を収納容器３内の上部、及び下部に取り付けて超伝導線材４を張設する。
【選択図】図１
The present invention makes it possible to compensate for the mechanical vulnerability of a superconducting wire and the vulnerability to heat, and to accurately measure a liquid level even for a low-temperature liquid such as liquid hydrogen that is difficult to detect. Provide superconducting liquid level gauge.
A superconducting wire 4 standing in a storage container 3 with at least a portion in contact with a cryogenic liquid 2, a power supply 7 for supplying a current to the superconducting wire 4, and an upper end of the superconducting wire 4 And a heater 8 that generates heat by a current supplied from a power source 7, and welded to both ends of the superconducting wire 4 is a conductive wire having at least a higher degree of processing than the superconducting wire 4. In a state where the connection portion and the power source 7 are electrically connected, the connection portion is attached to the upper and lower portions in the storage container 3 and the superconducting wire 4 is stretched.
[Selection] Figure 1
Description
本発明は、超伝導線材を用いて低温液体の液面を検出する超伝導液面計に関する。 The present invention relates to a superconducting liquid level gauge that detects a liquid level of a cryogenic liquid using a superconducting wire.
液体ヘリウム（大気圧下の沸点が約４Ｋ）のような超低温液体の液位を計測するため、ニオブ−チタン（ＮｂＴｉ）線材（臨界温度が約９Ｋ）を用いた超伝導液面計が一般的に知られている。超伝導液面計の動作原理は、容器内に鉛直に立設された超伝導線材に最適な電流を通電すると、液体中では電気抵抗ゼロの超伝導状態となり、気体中では抵抗がある常伝導状態となり、気体中の長さに比例した電圧値が出力されることで、その値に基づいて液位を算出するものである。 A superconducting liquid level gauge using niobium-titanium (NbTi) wire (critical temperature is about 9K) is generally used to measure the liquid level of ultra-low temperature liquid such as liquid helium (boiling point at atmospheric pressure is about 4K). Known to. The operating principle of the superconducting liquid level gauge is that when an optimal current is applied to a superconducting wire vertically installed in the container, it becomes a superconducting state with zero electrical resistance in the liquid, and normal conduction with resistance in the gas. By entering a state and outputting a voltage value proportional to the length in the gas, the liquid level is calculated based on that value.
近年注目されている液体水素（大気圧下の沸点が約２０Ｋ）の液面計として、静電容量方式の液面計が一般的に知られている。しかし、水素は密度が小さく、且つ液相と気相との比誘電率の差が非常に小さいため、液位を測定するには再較正が必要となり、作業に手間が掛かってしまうという問題がある。 As a liquid level gauge for liquid hydrogen (boiling point under atmospheric pressure of about 20K) that has been attracting attention in recent years, a capacitance type liquid level gauge is generally known. However, since hydrogen has a low density and the difference in relative permittivity between the liquid phase and the gas phase is very small, recalibration is required to measure the liquid level, and the work is troublesome. is there.
上記問題に関連して、比較的新しい超伝導体である２ホウ化マグネシウム（ＭｇＢ2）（臨界温度が約３９Ｋ）を利用した液体水素用の液面計が開示されている（例えば、特許文献１、２を参照）。特許文献１に示す液面測定装置は、液化水素容器、特に自動車用タンクに入った液化水素を対象とする、１つのタンクの内部に二ホウ化マグネシウムＭｇＢ2をベースとする１つの超伝導体が垂直に又は垂線に対して斜めに配置されるとともに、前記超伝導体の上側の領域に１つの可制御式熱源が配置されており、さらに前記超伝導体が１つの可制御式電源並びに１つの電圧測定装置に電気的に接触されるとともに、液面測定が電圧測定として構成される、超伝導式液面測定装置である。 In relation to the above problem, a liquid level gauge for liquid hydrogen using magnesium diboride (MgB 2 ) (critical temperature is about 39 K), which is a relatively new superconductor, has been disclosed (for example, patent document). 1 and 2). The liquid level measuring device shown in Patent Document 1 is a superconductor based on magnesium diboride MgB 2 in one tank for liquefied hydrogen containers, particularly liquefied hydrogen contained in an automobile tank. Are arranged vertically or obliquely to the normal, and one controllable heat source is disposed in the upper region of the superconductor, and the superconductor further comprises one controllable power source and one It is a superconducting liquid level measuring device that is electrically contacted with two voltage measuring devices and the liquid level measurement is configured as a voltage measurement.
特許文献２に示す技術は、少なくともその一部が極低温流体中に配置される液面検知部と、液面検知部に電流を供給する電源部と、液面検知部の電気抵抗を測定する抵抗測定部とを有し、液面検知部が二ホウ化マグネシウムから形成されていることを特徴とするものである。 The technique shown in Patent Document 2 measures the electrical resistance of a liquid level detection unit, at least part of which is disposed in a cryogenic fluid, a power supply unit that supplies current to the liquid level detection unit, and the liquid level detection unit. And a resistance measurement unit, and the liquid level detection unit is made of magnesium diboride.
上記ＭｇＢ2線材を含む多数の超伝導線材は、機械的に非常に脆く、少しの曲げや伸縮に対しても断線や損傷等を生じやすく、加工が非常に困難である。また、熱に対しても非常に脆く、外部からの熱や常伝導状態における電流により生じる内部の熱により、断線や損傷等を生じてしまう。 Many superconducting wires including the MgB 2 wire are mechanically very fragile, and are easily broken or damaged by a slight bending or stretching, and are very difficult to process. Moreover, it is very fragile with respect to heat, and disconnection, damage, and the like are caused by heat from the outside and internal heat generated by current in a normal state.
上記のような脆弱性を有する超伝導線材により低温液体の液位を測定する場合には、超伝導線材が低温液体を投入した中空の容器の内壁に接触することなく、鉛直に立設された状態を維持する必要があり、また、低温液体の液位や気体の状態に応じて超伝導線材の膨張率が頻繁に変化するため、そのような状態変化に対応できるように、超伝導線材が容器内で支持される必要がある。 When measuring the liquid level of a cryogenic liquid with a superconducting wire having the above-mentioned weakness, the superconducting wire was erected vertically without contacting the inner wall of a hollow container filled with the cryogenic liquid. It is necessary to maintain the state, and the expansion coefficient of the superconducting wire frequently changes depending on the liquid level of the low-temperature liquid and the state of the gas. Must be supported in a container.
さらに、超伝導液面計に利用する超伝導線材の場合は、通常の超伝導線と異なり、外部から熱を加えることで部分的に常伝導状態にする必要があると共に、常伝導状態の部分が存在することにより線材に過度の熱が生じてしまう可能性がある。そのため、熱の管理を非常に厳密に行う必要がある。 Furthermore, in the case of a superconducting wire used for a superconducting liquid level gauge, unlike a normal superconducting wire, it is necessary to make it partially normal by applying heat from the outside. Excessive heat may be generated in the wire due to the presence of. Therefore, it is necessary to perform heat management very strictly.
しかしながら、上記特許文献１、２では、超伝導線材の機械的な脆弱性や熱への脆弱性が考慮されておらず、超伝導線材が断線したり損傷を生じる可能性がある。特に、液体水素のように移動体の燃料として利用されるような低温液体の液位を測定する場合には、移動や振動により超伝導線材が湾曲したり、伸縮する可能性が高く、超伝導線材を中空内に立設することは困難となる。 However, in the above Patent Documents 1 and 2, the mechanical vulnerability of the superconducting wire and the vulnerability to heat are not considered, and the superconducting wire may be broken or damaged. In particular, when measuring the level of a low-temperature liquid such as liquid hydrogen that is used as a fuel for a moving body, the superconducting wire is likely to bend or expand or contract due to movement or vibration. It is difficult to stand the wire in the hollow.
そこで、本発明は超伝導線材の機械的な脆弱性や熱への脆弱性を補うと共に、液体水素のように液位の検出が困難な低温液体であっても正確に液位を測定することができる超伝導液面計を提供する。 Therefore, the present invention compensates for the mechanical vulnerability and heat vulnerability of the superconducting wire, and accurately measures the liquid level even for a low-temperature liquid such as liquid hydrogen where the liquid level is difficult to detect. Provide a superconducting liquid level gauge that can
（１）本願に開示する超伝導液面計は、直線状の超伝導線材を用いて収納容器内に収納された低温液体の液位を測定する超伝導液面計において、前記低温液体に少なくとも一部が接触した状態で前記収納容器内に立設する超伝導線材と、当該超伝導線材に電流を供給する電源部と、前記超伝導線材の上端部に配設され前記電源部から供給された電流により熱を発生する発熱部とを備え、前記超伝導線材の両端部に、少なくとも前記超伝導線材よりも加工度が大きい導電線を溶着して接続部を形成し、当該接続部と前記電源部とが電気的に接続された状態で、前記接続部を前記収納容器内の上部、及び下部に取り付けて前記超伝導線材を張設することを特徴とするものである。 (1) A superconducting liquid level meter disclosed in the present application is a superconducting liquid level meter that measures the liquid level of a cryogenic liquid stored in a storage container using a linear superconducting wire. A superconducting wire standing in the container with a part in contact, a power supply unit for supplying current to the superconducting wire, and an upper end portion of the superconducting wire, provided from the power supply unit A heat generating portion that generates heat by a current, and welded to each end of the superconducting wire at least with a conductive wire having a higher degree of processing than the superconducting wire to form a connecting portion, and the connecting portion and the The superconducting wire is stretched by attaching the connection portion to the upper and lower portions in the storage container in a state where the power supply portion is electrically connected.
このように、本願に開示する超伝導液面計においては、超伝導線材の両端部に、少なくとも超伝導線材よりも加工度が大きい導電線を溶着して接続部を形成し、接続部を収納容器内の上部、及び下部に取り付けて超伝導線材を張設することで、加工度が大きい導電線で形成される接続部により収納容器への取り付けが行われ、超伝導線材自体に対して変形等の加工を行う必要がなく直線状に維持することができ、加工による超伝導線材の断線や損傷を防止することができるという効果を奏する。 As described above, in the superconducting liquid level gauge disclosed in the present application, at least the conductive wires having a higher degree of processing than the superconducting wire are welded to both ends of the superconducting wire to form a connecting portion, and the connecting portion is accommodated. By attaching the superconducting wire to the upper and lower parts in the container, the superconducting wire itself is deformed by attaching to the storage container by the connection part formed of conductive wires with a high degree of processing. It is not necessary to perform such processing, and can be maintained in a straight line, and it is possible to prevent disconnection and damage of the superconducting wire due to processing.
（２）本願に開示する超伝導液面計は、前記収納容器内の上部に取り付けられる上部接続部が、伸縮性を有するバネ材を介して前記収納容器内に取り付けられることを特徴とするものである。
このように、本願に開示する超伝導液面計においては、上部接続部が、伸縮性を有するバネ材を介して収納容器内に取り付けられることで、超伝導線材の膨張率の変化による伸縮や、振動等による湾曲をバネ材で吸収し、超伝導線材への負荷を最小限に抑えて断線や損傷を防止することができるという効果を奏する。
(2) The superconducting liquid level gauge disclosed in the present application is characterized in that an upper connection portion attached to an upper portion in the storage container is attached to the storage container via a spring material having elasticity. It is.
As described above, in the superconducting liquid level gauge disclosed in the present application, the upper connection portion is attached to the storage container via the elastic spring material, so that the expansion and contraction due to the change in the expansion coefficient of the superconducting wire can be reduced. The bending due to vibration or the like is absorbed by the spring material, and the load on the superconducting wire can be minimized to prevent disconnection or damage.
（３）本願に開示する超伝導液面計は、前記上部接続部と前記バネ材との間にドーナツ状のリング体を備え、当該リング体が前記上部接続部で形成される環状体と連環して、当該上部接続部と前記バネ材とを接続することを特徴とするものである。
このように、本願に開示する超伝導液面計においては、上部接続部とバネ材との間にドーナツ状のリング体を備え、リング体が上部接続部で形成される環状体と連環して接続していることで、バネ材と上部接続部との接続箇所における変位（例えば、立設された超伝導線材の横方向の変位や周方向の回転変位等）に対しても超伝導線材への負荷が軽減され、断線や損傷を確実に防止することができるという効果を奏する。
(3) The superconducting liquid level gauge disclosed in the present application includes a donut-shaped ring body between the upper connection portion and the spring material, and the ring body is connected to an annular body formed by the upper connection portion. And the said upper connection part and the said spring material are connected, It is characterized by the above-mentioned.
As described above, in the superconducting liquid level gauge disclosed in the present application, the donut-shaped ring body is provided between the upper connection portion and the spring material, and the ring body is connected to the annular body formed by the upper connection portion. By connecting, the superconducting wire can also be displaced with respect to displacement at the connection point between the spring material and the upper connecting portion (for example, lateral displacement or circumferential rotational displacement of the standing superconducting wire). The load is reduced, and there is an effect that disconnection and damage can be surely prevented.
（４）本願に開示する超伝導液面計は、前記発熱部が、前記収納容器内の上部に取り付けられる接続部の表面に電気抵抗線を巻回して形成されることを特徴とするものである。
このように、本願に開示する超伝導液面計においては、発熱部が、収納容器内の上部に取り付けられる接続部の表面に電気抵抗線を巻回して形成されることで、超伝導線材に対して外部から直接熱が加わることを防止し、熱による断線や損傷を防止することができるという効果を奏する。
(4) The superconducting liquid level gauge disclosed in the present application is characterized in that the heat generating part is formed by winding an electric resistance wire around the surface of a connection part attached to the upper part in the storage container. is there.
Thus, in the superconducting liquid level meter disclosed in the present application, the heat generating part is formed by winding an electric resistance wire around the surface of the connecting part attached to the upper part in the storage container, so that the superconducting wire is formed. On the other hand, it is possible to prevent heat from being directly applied from the outside and to prevent disconnection or damage due to heat.
（５）本願に開示する超伝導液面計は、前記超伝導線材が、２ホウ化マグネシウム線材、ニオブ３スズ線材、並びにビスマス系、イットリウム系、及び希土類系各酸化物超伝導線材のいずれかであることを特徴とするものである。
このように、本願に開示する超伝導液面計においては、超伝導線材が、２ホウ化マグネシウム線材、ニオブ３スズ線材、並びにビスマス系、イットリウム系、及び希土類系各酸化物超伝導線材のいずれかであるため、このような機械的に脆弱な超伝導線材であっても断線や損傷を防止することができ、低温液体に適した様々な超伝導線材を用いて液位を測定することができるという効果を奏する。
(5) In the superconducting liquid level gauge disclosed in the present application, the superconducting wire is any of magnesium diboride wire, niobium and tritin wire, and bismuth, yttrium, and rare earth oxide superconducting wires. It is characterized by being.
Thus, in the superconducting liquid level gauge disclosed in the present application, the superconducting wire is any one of magnesium diboride wire, niobium 3 tin wire, and bismuth, yttrium, and rare earth oxide superconducting wires. Therefore, even such a mechanically fragile superconducting wire can prevent disconnection and damage, and the liquid level can be measured using various superconducting wires suitable for low-temperature liquids. There is an effect that can be done.
（６）本願に開示する超伝導液面計は、前記超伝導線材が２ホウ化マグネシウム線材であり、２ホウ化マグネシウムがステンレス鋼のみのシース材で被覆されていることを特徴とするものである。
このように、本願に開示する超伝導液面計においては、超伝導線材が２ホウ化マグネシウム線材であり、２ホウ化マグネシウムが抵抗率の温度依存性が低いステンレス鋼のみのシース材で被覆されているため、特に対流が大きい気体中における温度分布の激しい変化に対して、その影響を最小限に抑え再現性のよい測定を行うことができるという効果を奏する。また、発生電圧と液面位置との１対１対応の線形性（直線性）が良くなって換算し易くなるという効果を奏する。さらに、センサ長を長くすると発生電圧が急増するため長さに限界があるが、その問題を解決することができるという効果を奏する。
(6) The superconducting liquid level meter disclosed in the present application is characterized in that the superconducting wire is a magnesium diboride wire, and the magnesium diboride is covered with a sheath material made only of stainless steel. is there.
Thus, in the superconducting liquid level gauge disclosed in the present application, the superconducting wire is a magnesium diboride wire, and the magnesium diboride is coated with a sheath material made only of stainless steel whose resistivity has low temperature dependency. Therefore, an effect is obtained that measurement with good reproducibility can be performed while minimizing the influence on a drastic change in temperature distribution particularly in a gas having a large convection. In addition, the linearity (linearity) corresponding to one-to-one correspondence between the generated voltage and the liquid surface position is improved, and the conversion is facilitated. Furthermore, when the sensor length is increased, the generated voltage increases rapidly, so that the length is limited. However, the problem can be solved.
（７）本願に開示する超伝導液面計は、前記２ホウ化マグネシウム線材の線径が０．１ないし０．２ｍｍであることを特徴とするものである。
このように、本願に開示する超伝導液面計においては、２ホウ化マグネシウム線材の線径が０．１ないし０．２ｍｍであるため、２ホウ化マグネシウム線材の長手方向の密度を均一に加工することができ、正確な液位の測定が可能になるという効果を奏する。また、動作電流を低減させ、発熱による液体水素の余分な蒸発を防止することができるという効果を奏する。
(7) The superconducting liquid level gauge disclosed in the present application is characterized in that the magnesium diboride wire has a wire diameter of 0.1 to 0.2 mm.
Thus, in the superconducting liquid level gauge disclosed in the present application, since the wire diameter of the magnesium diboride wire is 0.1 to 0.2 mm, the density in the longitudinal direction of the magnesium diboride wire is uniformly processed. This is advantageous in that the liquid level can be accurately measured. In addition, there is an effect that the operating current can be reduced and excessive evaporation of liquid hydrogen due to heat generation can be prevented.
以下、本発明の実施の形態を説明する。本発明は多くの異なる形態で実施可能である。従って、本実施形態の記載内容のみで本発明を解釈すべきではない。また、本実施形態の全体を通して同じ要素には同じ符号を付けている。 Embodiments of the present invention will be described below. The present invention can be implemented in many different forms. Therefore, the present invention should not be construed based only on the description of the present embodiment. Also, the same reference numerals are given to the same elements throughout the present embodiment.
（本発明の実施形態）
本実施形態に係る超伝導液面計について、図１ないし図４を用いて説明する。図１は、本実施形態に係る超伝導液面計の全体構成図、図２は、本実施形態に係る超伝導液面計の構成を示す図、図３は、本実施形態に係る超伝導液面計における超伝導線材の両端部の加工を示す図、図４は、本実施形態に係る超伝導液面計における接続部を示す図である。
(Embodiment of the present invention)
The superconducting liquid level meter according to this embodiment will be described with reference to FIGS. FIG. 1 is an overall configuration diagram of a superconducting liquid level meter according to the present embodiment, FIG. 2 is a diagram illustrating a configuration of the superconducting liquid level meter according to the present embodiment, and FIG. 3 is a superconducting property according to the present embodiment. The figure which shows the process of the both ends of the superconducting wire in a liquid level gauge, FIG. 4 is a figure which shows the connection part in the superconducting liquid level gauge which concerns on this embodiment.
図１において、超伝導液面計１は、液面測定の測定対象となる低温液体２、低温液体２を収納する収納容器３、低温液体２に少なくとも一部が接触した状態で収納容器３内に立設する超伝導線材４、超伝導線材４を外部と電気的に接続するための上下におけるそれぞれの上電極５と下電極６、上電極５と下電極６とに接続し外部から電流を供給する電源７、電源７から供給された電流により発熱し超伝導線材４の上端部から熱を供給するヒータ８、及び超伝導線材４にかかる電圧を測定する電圧計９を備える。 In FIG. 1, a superconducting liquid level gauge 1 includes a cryogenic liquid 2 to be measured for liquid level measurement, a storage container 3 for storing the cryogenic liquid 2, and the inside of the storage container 3 with at least a part in contact with the cryogenic liquid 2. Are connected to the upper electrode 5 and the lower electrode 6 and the upper electrode 5 and the lower electrode 6 in the upper and lower sides for electrically connecting the superconducting wire 4 to the outside, and current is supplied from the outside. The power supply 7 to supply, the heater 8 which generate | occur | produces with the electric current supplied from the power supply 7, and supplies heat from the upper end part of the superconducting wire 4, and the voltmeter 9 which measures the voltage concerning the superconducting wire 4 are provided.
超伝導液面計１による低温液体２の液面位置は、電圧計９に出力される電圧値により求めることができる。つまり、低温液体２に浸漬している部分の超伝導線材４は、超伝導状態になっており、低温液体２に浸漬していない部分の超伝導線材４は、常伝導状態になっている。したがって、低温液体２の液面の位置に応じて超伝導線材４全体の抵抗値が変化し、その値を出力することで液面の位置を算出することができる。このとき、ヒータ８により熱を供給することで低温液体２に浸漬していない部分（気体部分）を確実に常伝導状態にしている。 The liquid level position of the low temperature liquid 2 by the superconducting liquid level meter 1 can be obtained from the voltage value output to the voltmeter 9. That is, the portion of the superconducting wire 4 immersed in the low-temperature liquid 2 is in a superconducting state, and the portion of the superconducting wire 4 not immersed in the low-temperature liquid 2 is in a normal conducting state. Accordingly, the resistance value of the entire superconducting wire 4 changes according to the position of the liquid surface of the low temperature liquid 2, and the liquid surface position can be calculated by outputting the value. At this time, by supplying heat from the heater 8, a portion (gas portion) not immersed in the low temperature liquid 2 is surely brought into a normal conduction state.
本実施形態においては、低温液体２が主に液体水素であり、大気圧下の沸点が約２０Ｋである。また、超伝導線材４は、液体水素中でも超伝導状態に転移するＭｇＢ2（臨界温度が約３９Ｋ）線材を使用する。超伝導線材４は、中心にＭｇＢ2を有し、その外側をＳＵＳ（ステンレス鋼）／Ｆｅ（鉄）シース、又はＳＵＳのみのシースで被覆している。ＳＵＳのみのシースを用いた場合には、抵抗率の温度依存性を小さくすることができるため、収納容器３内の気体中の状態変化（温度変化）に対して安定的な抵抗率となり、再現性を良くすることができる。また、発生電圧と液面位置との１対１対応の線形性（直線性）が良くなって換算し易くなることに加え、センサ長を長くすると発生電圧が急増するため長さに限界があるという問題を解決することができる。
なお、図１においてはヒータ８と超伝導線材４に電流を供給する電源を一つの電源７としているが、ヒータ８用の電源と超伝導線材４用の電源とに分けてもよい。
In this embodiment, the low temperature liquid 2 is mainly liquid hydrogen, and the boiling point under atmospheric pressure is about 20K. The superconducting wire 4 is a MgB 2 (critical temperature is about 39K) wire that transitions to a superconducting state even in liquid hydrogen. The superconducting wire 4 has MgB 2 at the center, and the outside is covered with a SUS (stainless steel) / Fe (iron) sheath or a sheath made of SUS only. When a sheath made of SUS only is used, the temperature dependence of the resistivity can be reduced, so that the resistivity becomes stable with respect to the state change (temperature change) in the gas in the storage container 3 and is reproduced. The sex can be improved. In addition, the linearity (linearity) corresponding to one-to-one correspondence between the generated voltage and the liquid surface position is improved and conversion is facilitated. In addition, when the sensor length is increased, the generated voltage increases rapidly, so the length is limited. Can be solved.
In FIG. 1, the power source for supplying current to the heater 8 and the superconducting wire 4 is a single power source 7, but it may be divided into a power source for the heater 8 and a power source for the superconducting wire 4.
図２は超伝導液面計１の構成を示す図である。図２（Ａ）が超伝導液面計１の測定部分の断面図であり、図２（Ｂ）が、収納容器３の内部構成図である。図２（Ａ）において、超伝導線材４は内側プラスチックパイプ１５内に、当該内側プラスチックパイプ１５に接触しないように上下に張設されて保持されている。内側プラスチックパイプ１５は、外側ステンレスパイプ１６に被覆されて保護されており、外部からの入熱の防止や機械的な強度を保障している。 FIG. 2 is a diagram showing the configuration of the superconducting liquid level gauge 1. 2A is a cross-sectional view of the measurement portion of the superconducting liquid level gauge 1, and FIG. 2B is an internal configuration diagram of the storage container 3. FIG. In FIG. 2A, the superconducting wire 4 is stretched up and down so as not to contact the inner plastic pipe 15 in the inner plastic pipe 15. The inner plastic pipe 15 is covered and protected by the outer stainless steel pipe 16 to prevent heat input from the outside and mechanical strength.
超伝導線材４の両端部には、上電極５、下電極６を介して超伝導線材４に電流を供給するためのリード線が接続されており（接続部分の詳細は図示しない）、それぞれのリード線は外部の電源７に接続される。
なお、ヒータ８用の電源と超伝導線材４用の電源を分ける場合は、ヒータ８用のリード線を備え、同様にヒータ８用の電源に接続するようにしてもよい。
Lead wires for supplying current to the superconducting wire 4 are connected to both ends of the superconducting wire 4 via the upper electrode 5 and the lower electrode 6 (details of the connecting portion are not shown). The lead wire is connected to an external power source 7.
When the power supply for the heater 8 and the power supply for the superconducting wire 4 are separated, a lead wire for the heater 8 may be provided and similarly connected to the power supply for the heater 8.
図２（Ｂ）において、超伝導線材４の両端部には、上電極５と下電極６とが形成されている。上電極５にはヒータ８となる抵抗発熱線が巻回されている。ヒータ８に電流が供給されると、抵抗発熱線からの発熱により超伝導線材４が温められて低温液体２に浸漬していない部分が常伝導状態となる。 In FIG. 2B, an upper electrode 5 and a lower electrode 6 are formed at both ends of the superconducting wire 4. A resistance heating wire serving as a heater 8 is wound around the upper electrode 5. When a current is supplied to the heater 8, the superconducting wire 4 is warmed by the heat generated from the resistance heating wire, and the portion that is not immersed in the low-temperature liquid 2 becomes a normal conduction state.
超伝導線材４の上端部は、上電極５、ドーナツ状のリング体１１、及びバネ材１２を介して、上部支持体１４に支持されている。超伝導線材４の下端部は、下電極６を介して電極金具１３に支持されている。それぞれの端部における詳細な構成については図４を用いて後述する。 The upper end portion of the superconducting wire 4 is supported by the upper support 14 via the upper electrode 5, the donut-shaped ring body 11, and the spring material 12. The lower end portion of the superconducting wire 4 is supported by the electrode fitting 13 via the lower electrode 6. A detailed configuration at each end will be described later with reference to FIG.
超伝導線材４と上部支持体１４との間にバネ材１２を介することで、バネの弾性力により超伝導線材４が張設され、超伝導線材４を内側プラスチックパイプ１５内の中空領域にその内面と接触することなく支持することができる。また、装置内の温度状態に応じて超伝導線材４が膨張、収縮を繰り返して行うため、上部支持体１４と電極金具１３に固定されてしまうと、その変位により超伝導線材４に断線、損傷等が生じてしまう。つまり、バネ材１２の弾性力が膨張、収縮による超伝導線材４の体積変化を吸収することで、断線、損傷等を防止することができる。 By passing the spring material 12 between the superconducting wire 4 and the upper support 14, the superconducting wire 4 is stretched by the elastic force of the spring, and the superconducting wire 4 is placed in the hollow region in the inner plastic pipe 15. It can support without contacting the inner surface. Further, since the superconducting wire 4 is repeatedly expanded and contracted according to the temperature state in the apparatus, if it is fixed to the upper support 14 and the electrode fitting 13, the superconducting wire 4 is broken or damaged by the displacement. Etc. will occur. That is, the elastic force of the spring material 12 absorbs the volume change of the superconducting wire 4 due to expansion and contraction, so that disconnection, damage, and the like can be prevented.
また、バネ材１２と上電極５との間にリング体１１を介することで、超伝導液面計１の横方向の移動に伴う超伝導線材４のブレや振動を和らげると共に、超伝導線材４の捻りをなくして断線、損傷等を防止することができる。 Further, by interposing the ring body 11 between the spring material 12 and the upper electrode 5, the superconducting wire 4 can be reduced in vibration and vibration due to the lateral movement of the superconducting liquid level gauge 1 and the superconducting wire 4. It is possible to prevent disconnection, damage and the like by eliminating twisting of the wire.
図３は、超伝導線材４の両端部の加工を示す図である。ＭｇＢ2線材は、高い温度で超伝導状態に転移することができるが、従来から超伝導線材として一般的に利用されているＮｂ−Ｔｉ合金等に比べて機械的に脆いため、曲げや伸線等を自由に行うことができず、無理な加工を行おうとすると断線、損傷等を生じてしまう。そのため、超伝導線材４の両端部をいかに機械的な加工をせずに収納容器３内の中空領域に支持できるかが非常に重要である。本実施形態においては、超伝導線材４の両端部に機械的な強度が大きく、自由に加工できる銅線を溶着して接続部を形成する。 FIG. 3 is a diagram showing processing of both end portions of the superconducting wire 4. MgB 2 wire can transition to a superconducting state at a high temperature. However, since it is mechanically brittle compared to Nb—Ti alloys or the like that have been conventionally used as a superconducting wire, bending and wire drawing are possible. Etc. cannot be performed freely, and disconnection, damage, etc. will occur if an unreasonable process is performed. Therefore, it is very important how both ends of the superconducting wire 4 can be supported in the hollow region in the storage container 3 without mechanical processing. In the present embodiment, the connection portion is formed by welding a copper wire that has high mechanical strength and can be freely processed at both ends of the superconducting wire 4.
まず、図３（Ａ）に示すように、超伝導線材４の銅コーティング部４ａ（例えば、長さを１０ｍｍ程度とする）に、銅線３１をオーバーラップさせる。オーバーラップした部分に、銅線３１よりも細い銅線３１ａを巻回して、銅コーティング部４ａと銅線３１とを密着させる。その状態でオーバーラップ部分に半田付けをして接続部を形成する。そして、図３（Ｂ）に示すように、形成された接続部における上電極５となる部分に対してヒータ８の抵抗発熱線を巻回する。ヒータ８を接続部におけるオーバーラップした部分に巻回することで、超伝導線材４がヒータ８の熱を直接受けて損傷してしまうことを防止することができる。 First, as shown in FIG. 3A, the copper wire 31 is overlapped with the copper coating portion 4a of the superconducting wire 4 (for example, the length is about 10 mm). A copper wire 31a thinner than the copper wire 31 is wound around the overlapped portion, and the copper coating portion 4a and the copper wire 31 are brought into close contact with each other. In this state, the overlapping portion is soldered to form a connection portion. And as shown in FIG.3 (B), the resistance heating wire of the heater 8 is wound around the part used as the upper electrode 5 in the formed connection part. By winding the heater 8 around the overlapping portion in the connection portion, it is possible to prevent the superconducting wire 4 from being directly damaged by the heat of the heater 8.
このように形成された接続部（上電極５、下電極６を含む銅線部分）に対して伸線、曲げ等の加工を行うことで、超伝導線材４には外部からの力が直接加わることがなく、断線や損傷等を確実に防止することができる。 By applying a process such as wire drawing and bending to the connecting portion thus formed (copper wire portion including the upper electrode 5 and the lower electrode 6), a force from the outside is directly applied to the superconducting wire 4. It is possible to reliably prevent disconnection and damage.
図４は、接続部の加工の具体例を示す図である。図４（Ａ）が上端部における接続部の加工を示し、図４（Ｂ）が下端部における接続部の加工を示す。図４（Ａ）においては、上記のように超伝導線材４が、上電極５、リング体１１、及びバネ材１２を介して上部支持体１４に支持されている。 FIG. 4 is a diagram illustrating a specific example of the processing of the connecting portion. FIG. 4A shows the processing of the connecting portion at the upper end, and FIG. 4B shows the processing of the connecting portion at the lower end. 4A, the superconducting wire 4 is supported on the upper support 14 via the upper electrode 5, the ring body 11, and the spring material 12 as described above.
接続部の上端部には、半田付けにより環状に形成した環状体４１を有しており、この環状体４１とリング体１１とが連環している。また、バネ材１２の下端部にも、半田付け等により環状に形成した環状体４２を有しており、この環状体４２とリング体１１とが連環している。つまり、図４（Ａ）に示すように環状体４１と環状体４２とがリング体１１を介して連環して接続されている。このように接続されることで、超伝導線材４の横方向の移動や捻れを最小限に抑えることができる。 An annular body 41 formed in an annular shape by soldering is provided at the upper end portion of the connecting portion, and the annular body 41 and the ring body 11 are connected. In addition, the lower end portion of the spring material 12 has an annular body 42 formed in an annular shape by soldering or the like, and the annular body 42 and the ring body 11 are connected. That is, as shown in FIG. 4A, the annular body 41 and the annular body 42 are connected to each other via the ring body 11. By being connected in this way, lateral movement and twisting of the superconducting wire 4 can be minimized.
図４（Ｂ）においては、接続部が電極金具１３を下方向に貫通し、電極金具１３の底部に沿って略９０度に曲折されている。曲折箇所は半田付けにより固定され、余分な箇所はニッパにより切断しておく。つまり、超伝導線材４の上端部はある程度可動自在に支持され、超伝導線材４の下端部は固定されて支持されている。 In FIG. 4B, the connecting portion penetrates the electrode fitting 13 downward and is bent at approximately 90 degrees along the bottom of the electrode fitting 13. The bent part is fixed by soldering, and the excess part is cut with a nipper. That is, the upper end portion of the superconducting wire 4 is supported so as to be movable to some extent, and the lower end portion of the superconducting wire 4 is fixedly supported.
このように、接続部が、銅線のように加工度が大きい材料により形成されているため、環状に変形したり略９０度に曲折しても機械的に安定させることができ、超伝導線材４を中空内で安定して立設することができる。また、リング体１１を介してバネ材１２と連環して接続されているため、横方向や捻れに対しての負荷を最小限に抑えつつ、バネ材１２により縦方向の負荷を吸収することができ、超伝導線材４の断線、損傷等を防止することができる。 Thus, since the connection portion is formed of a material having a high degree of processing such as a copper wire, it can be mechanically stabilized even if it is deformed into an annular shape or bent at approximately 90 degrees, and is a superconducting wire. 4 can be erected stably in the hollow. Further, since it is connected to the spring material 12 via the ring body 11, it is possible to absorb the load in the vertical direction by the spring material 12 while minimizing the load against the lateral direction and the twist. It is possible to prevent the superconducting wire 4 from being disconnected or damaged.
次に、本実施形態に係る超伝導液面計の動作について説明する。収納容器３内に低温液体２が投入され、超伝導線材４の下部における低温液体２に浸漬する部分が、低温液体２の温度（液体水素の場合は約２０Ｋ）に冷却される。ＭｇＢ2の臨界温度が３９Ｋ程度であるため、低温液体２（液体水素）に浸漬している部分は超伝導状態に転移して電気抵抗がゼロ抵抗となる。 Next, the operation of the superconducting liquid level gauge according to this embodiment will be described. The cryogenic liquid 2 is introduced into the storage container 3, and the portion immersed in the cryogenic liquid 2 at the lower part of the superconducting wire 4 is cooled to the temperature of the cryogenic liquid 2 (about 20 K in the case of liquid hydrogen). Since the critical temperature of MgB 2 is about 39K, the portion immersed in the low-temperature liquid 2 (liquid hydrogen) transitions to the superconducting state and the electric resistance becomes zero resistance.
また、同時にヒータ８に電流を供給しヒータ８を発熱させる。超伝導線材４の上部における低温液体２に浸漬していない部分は、上端部の方向からヒータ８により熱が伝えられて温度が上昇する。つまり、低温液体２に浸漬していない部分は、温度が臨界温度以上となり常伝導状態に転移して抵抗値が発生する。 At the same time, a current is supplied to the heater 8 to cause the heater 8 to generate heat. The portion of the upper portion of the superconducting wire 4 that is not immersed in the low-temperature liquid 2 is heated by the heater 8 from the direction of the upper end, and the temperature rises. That is, the portion not immersed in the low temperature liquid 2 has a temperature equal to or higher than the critical temperature, transitions to a normal state, and generates a resistance value.
この超伝導線材に所定の電流値を供給し、電圧値（抵抗値）を測定する。得られた抵抗値から超伝導状態部分又は常伝導状態部分の長さを算出して、液面の位置を測定する。
なお、本実施形態に係る超伝導液面計は、主にＭｇＢ2線材を超伝導線材４として用いることとしたが、超伝導線材４は、超伝導特性を示す線材であれば何でもよく、例えばＮｂ−Ｔｉのように比較的加工が容易であるものから、ニオブ３スズ線材、並びにビスマス系、イットリウム系、及び希土類系各酸化物超伝導線材等のように加工が困難なものまで適用することができる。
A predetermined current value is supplied to the superconducting wire, and a voltage value (resistance value) is measured. The length of the superconducting state part or the normal conduction state part is calculated from the obtained resistance value, and the position of the liquid level is measured.
In the superconducting liquid level gauge according to the present embodiment, the MgB 2 wire is mainly used as the superconducting wire 4. However, the superconducting wire 4 may be any wire as long as it exhibits superconducting characteristics, for example, Applicable to materials that are relatively easy to process, such as Nb-Ti, and those that are difficult to process, such as niobium 3 tin wire, bismuth, yttrium, and rare earth oxide superconducting wires. Can do.
また、超伝導線材４の線径は、適宜設計可能であるが、好ましくは０．１ないし０．２ｍｍ程度がよい。そうすることで、長手方向に均一な超伝導線材４を形成することができる。
このように、本実施形態に係る超伝導液面計によれば、超伝導線材４の両端部に、少なくとも超伝導線材４よりも加工度が大きい銅線を溶着して接続部を形成し、接続部を収納容器３内の上部、及び下部に取り付けて超伝導線材４を張設することで、加工度が大きい銅線で形成される接続部により収納容器３への取り付けが行われ、超伝導線材４自体を変形等させる必要がなく直線状に維持することができ、変形等による超伝導線材４の断線や損傷を防止することができる。
The wire diameter of the superconducting wire 4 can be designed as appropriate, but is preferably about 0.1 to 0.2 mm. By doing so, the superconducting wire 4 uniform in the longitudinal direction can be formed.
Thus, according to the superconducting liquid level meter according to the present embodiment, a copper wire having a degree of processing larger than at least the superconducting wire 4 is welded to both ends of the superconducting wire 4 to form a connection portion. By attaching the connection part to the upper part and the lower part in the storage container 3 and stretching the superconducting wire 4, the connection part formed by a copper wire having a high degree of processing is attached to the storage container 3, The conductive wire 4 itself does not need to be deformed and can be maintained in a straight line, and disconnection or damage of the superconducting wire 4 due to deformation or the like can be prevented.
また、超伝導線材４の上端部の接続部が、伸縮性を有するバネ材１２を介して収納容器３内に取り付けられることで、超伝導線材４の膨張率の変化による変形や、振動等による湾曲や伸縮をバネ材１２で吸収し、超伝導線材４への負荷を最小限に抑えて断線や損傷を防止することができる。 Moreover, the connection part of the upper end part of the superconducting wire 4 is attached in the storage container 3 via the spring material 12 which has a stretching property, By deformation | transformation by the expansion coefficient change of a superconducting wire 4, vibration, etc. The bending and expansion / contraction are absorbed by the spring material 12, and the load on the superconducting wire 4 can be minimized to prevent disconnection or damage.
さらに、超伝導線材４の上端部の接続部とバネ材１２との間にドーナツ状のリング体１１を備え、リング体１１が上端部の接続部で形成される環状体４１と連環していることで、バネ材１２と接続部との接続箇所における変位（例えば、超伝導線材４の左右方向の変位や周方向への回転変位等）に対しても超伝導線材４への負荷が軽減され、断線や損傷を確実に防止することができる。 Further, a donut-shaped ring body 11 is provided between the connection portion at the upper end of the superconducting wire 4 and the spring material 12, and the ring body 11 is connected to an annular body 41 formed by the connection portion at the upper end. As a result, the load on the superconducting wire 4 is reduced even with respect to the displacement (for example, the lateral displacement of the superconducting wire 4 or the rotational displacement in the circumferential direction) of the connection portion between the spring material 12 and the connecting portion. Disconnection and damage can be reliably prevented.
さらにまた、ヒータ８が、収納容器３内の上部に取り付けられる接続部の表面に電気抵抗線を巻回して形成されることで、超伝導線材４に対して外部から直接熱が加わることを防止し、熱による断線や損傷を防止することができる。 Furthermore, since the heater 8 is formed by winding an electric resistance wire around the surface of the connecting portion attached to the upper part in the storage container 3, it is possible to prevent heat from being directly applied to the superconducting wire 4 from the outside. In addition, disconnection and damage due to heat can be prevented.
さらにまた、超伝導線材４に、２ホウ化マグネシウム線材、ニオブ３スズ線材、並びにビスマス系、イットリウム系、及び希土類系各酸化物超伝導線材等を適用可能であるため、機械的に脆弱な超伝導線材であっても断線や損傷を防止することができ、低温液体２に適した様々な超伝導線材４を用いて液位を測定することができる。 Furthermore, since the superconducting wire 4 can be applied with magnesium diboride wire, niobium 3 tin wire, bismuth, yttrium, and rare earth oxide superconducting wires, etc. Even if it is a conductive wire, disconnection and damage can be prevented, and the liquid level can be measured using various superconductive wires 4 suitable for the low temperature liquid 2.
さらにまた、超伝導線材４が２ホウ化マグネシウム線材であり、２ホウ化マグネシウムが抵抗率の温度依存性が低いステンレス鋼のみのシース材で被覆されることで、特に対流が大きい気体中における温度分布の激しい変化に対して、その影響を最小限に抑え再現性のよい測定を行うことができる。また、発生電圧と液面位置との１対１対応の線形性（直線性）が良くなって換算し易くなることに加え、センサ長を長くすると発生電圧が急増するため長さに限界がある問題を解決することができる。 Furthermore, the superconducting wire 4 is a magnesium diboride wire, and the magnesium diboride is covered with a sheath material made only of stainless steel having a low temperature dependence of resistivity. Measurements with high reproducibility can be performed with minimal influence on severe changes in distribution. In addition, the linearity (linearity) corresponding to one-to-one correspondence between the generated voltage and the liquid surface position is improved and conversion is facilitated. In addition, when the sensor length is increased, the generated voltage increases rapidly, so the length is limited. The problem can be solved.
さらにまた、２ホウ化マグネシウム線材の線径を０．１ないし０．２ｍｍとすることで、２ホウ化マグネシウム線材の長手方向の密度を均一に加工することができ、正確な液位の測定が可能になる。また、動作電流を低減させ、発熱による液体水素の余分な蒸発を防止することができる。 Furthermore, by setting the wire diameter of the magnesium diboride wire to 0.1 to 0.2 mm, the density in the longitudinal direction of the magnesium diboride wire can be processed uniformly, and accurate liquid level measurement is possible. It becomes possible. Further, the operating current can be reduced, and excessive evaporation of liquid hydrogen due to heat generation can be prevented.
本発明の実施例を以下に説明する。図５は、本実施例で使用するＭｇＢ2の超伝導線材を示す図である。図５（Ａ）が超伝導線材の断面図であり、図５（Ｂ）が超伝導線材の抵抗率の温度依存性を示すグラフである。本実施例で使用するＭｇＢ2線材は、ＳＵＳ／Ｆｅシース内にＭｇＢ2を配置した構成となっており、径が０．１ｍｍφ、ＭｇＢ2コアの断面積が０．００１４ｍｍ2、シース／コア断面積比が４．６９、臨界温度（自己磁場中）が３６Ｋである。 Examples of the present invention will be described below. FIG. 5 is a diagram showing a MgB 2 superconducting wire used in this example. FIG. 5A is a cross-sectional view of the superconducting wire, and FIG. 5B is a graph showing the temperature dependence of the resistivity of the superconducting wire. The MgB 2 wire used in this example has a configuration in which MgB 2 is disposed in a SUS / Fe sheath, the diameter is 0.1 mmφ, the cross-sectional area of the MgB 2 core is 0.0014 mm 2 , and the sheath / core breakage The area ratio is 4.69, and the critical temperature (in a self-magnetic field) is 36K.
（液体ヘリウムでの実験）
図５のＭｇＢ2線材を上記実施の形態に示すように中空の容器内に張設し、センサ長を３００ｍｍとした超伝導液面計に、液体ヘリウムを投入してその液面を測定した結果を図６に示す。図６において横軸が気体中の長さで、縦軸が発生電圧である。なお、気体中の長さについては従来から使用されているＮｂＴｉ線材を併設して液位を測定し、その値から算出している。
図６に示すように、１．１Ａを通電した場合も１．２Ａを通電した場合も、共に液位と電圧とが１対１で対応しており、電圧に応じて正確に液位を測定することができる。
(Experiment with liquid helium)
As shown in the above embodiment, the MgB 2 wire shown in FIG. 5 is stretched in a hollow container, and the liquid level is measured by introducing liquid helium into a superconducting liquid level gauge with a sensor length of 300 mm. Is shown in FIG. In FIG. 6, the horizontal axis represents the length in the gas, and the vertical axis represents the generated voltage. In addition, about the length in gas, the liquid level is measured by adding the NbTi wire conventionally used, and it calculates from the value.
As shown in Fig. 6, the liquid level and the voltage correspond one-to-one with both 1.1A and 1.2A, and the liquid level is accurately measured according to the voltage. can do.
（液体水素での実験）
図５のＭｇＢ2線材を上記実施の形態に示すように中空の容器内に張設し、センサ長を３００ｍｍとした超伝導液面計に、液体水素を投入してその液面を測定した結果を図７に示す。図７において横軸が気体中の長さで、縦軸が発生電圧である。なお、気体中の長さについては、液体水素を一定の速度で投入することで、その液量から算出したものである。
(Experiment with liquid hydrogen)
As shown in the above embodiment, the MgB 2 wire shown in FIG. 5 is stretched in a hollow container, and the liquid level is measured by introducing liquid hydrogen into a superconducting liquid level gauge with a sensor length of 300 mm. Is shown in FIG. In FIG. 7, the horizontal axis is the length in the gas, and the vertical axis is the generated voltage. The length in the gas is calculated from the amount of liquid by charging liquid hydrogen at a constant rate.
図７に示すように、０．６Ａを通電した場合も０．７Ａを通電した場合も、共に液位と電圧とが１対１で対応しており、電圧に応じて正確に液位を測定することができる。しかし、図７のグラフから回帰曲線を算出すると、気体中の長さが０の場合でも電圧値が０になっていない。これは、ＭｇＢ2線材に不健全な箇所があり、その部分が超伝導状態に転移することができずに電圧が発生した可能性がある。 As shown in Fig. 7, the liquid level and the voltage correspond one-to-one with both 0.6A and 0.7A, and the liquid level is accurately measured according to the voltage. can do. However, when the regression curve is calculated from the graph of FIG. 7, the voltage value is not 0 even when the length in the gas is 0. This is because there is an unhealthy part in the MgB 2 wire, and the part may not be transferred to the superconducting state, and voltage may have occurred.
このように、本発明に係る超伝導液面計は、ＭｇＢ2線材の機械的な脆弱性や熱への脆弱性の問題を解決し、中空の容器内に張設させて正確な超伝導液面計として機能させることができる。また、線径を０．１ないし０．２ｍｍとすることで、動作電流を低減させ、発熱による液体水素の余分な蒸発を防止し、線材の長手方向への均一性を保つことができる。 Thus, the superconducting liquid level meter according to the present invention solves the problems of mechanical vulnerability and heat vulnerability of the MgB 2 wire, and is stretched in a hollow container to provide an accurate superconducting liquid. It can function as a surface meter. In addition, by setting the wire diameter to 0.1 to 0.2 mm, it is possible to reduce the operating current, prevent excessive evaporation of liquid hydrogen due to heat generation, and maintain the uniformity of the wire in the longitudinal direction.
さらに、図８に示すように線材の抵抗率の温度依存性を小さくすることで、発生電圧と液面位置との１対１対応の線形性（直線性）が良くなって換算し易くなることに加えて、センサ長を長くすると発生電圧が急増するため長さに限界がある問題があるが、その問題を解決することができる。さらにまた、気体中の温度や圧力の条件にあまり影響されず、再現性を良くすることができる。 Furthermore, as shown in FIG. 8, by reducing the temperature dependency of the resistivity of the wire, the linearity (linearity) corresponding to the generated voltage and the liquid surface position is improved and becomes easy to convert. In addition, if the sensor length is increased, the generated voltage increases rapidly, so there is a problem that the length is limited. However, this problem can be solved. Furthermore, reproducibility can be improved without being significantly affected by the temperature and pressure conditions in the gas.
１ 超伝導液面計
２ 低温液体
３ 収納容器
４ 超伝導線材
５ 上電極
６ 下電極
７ 電源
８ ヒータ
９ 電圧計
１１ リング体
１２ バネ材
１３ 電極金具
１４ 上部支持体
１５ 内側プラスチックパイプ
１６ 外側ステンレスパイプ
３１ 銅線
４１，４２ 環状体
DESCRIPTION OF SYMBOLS 1 Superconducting liquid level meter 2 Cryogenic liquid 3 Storage container 4 Superconducting wire 5 Upper electrode 6 Lower electrode 7 Power supply 8 Heater 9 Voltmeter 11 Ring body 12 Spring material 13 Electrode metal fitting 14 Upper support 15 Inner plastic pipe 16 Outer stainless steel pipe 31 Copper wire 41, 42 Toroid
Claims (7)
前記低温液体に少なくとも一部が接触した状態で前記収納容器内に立設する超伝導線材と、当該超伝導線材に電流を供給する電源部と、前記超伝導線材の上端部に配設され前記電源部から供給された電流により熱を発生する発熱部とを備え、
前記超伝導線材の両端部に、少なくとも前記超伝導線材よりも加工度が大きい導電線を溶着して接続部を形成し、当該接続部と前記電源部とが電気的に接続された状態で、前記接続部を前記収納容器内の上部、及び下部に取り付けて前記超伝導線材を張設することを特徴とする超伝導液面計。 In a superconducting liquid level gauge that measures the liquid level of a cryogenic liquid stored in a storage container using a linear superconducting wire,
A superconducting wire standing in the container with at least a portion in contact with the cryogenic liquid, a power supply for supplying current to the superconducting wire, and an upper end of the superconducting wire A heat generating part that generates heat by the current supplied from the power supply part,
At both ends of the superconducting wire, at least a conductive wire having a higher degree of processing than the superconducting wire is welded to form a connection portion, and the connection portion and the power supply portion are electrically connected. The superconducting liquid level gauge is characterized in that the superconducting wire is stretched by attaching the connecting part to an upper part and a lower part in the container.
前記収納容器内の上部に取り付けられる上部接続部が、伸縮性を有するバネ材を介して前記収納容器内に取り付けられることを特徴とする超伝導液面計。 In the superconducting liquid level meter according to claim 1,
The superconducting liquid level gauge, wherein an upper connection portion attached to an upper portion in the storage container is attached in the storage container via a spring material having elasticity.
前記上部接続部と前記バネ材との間にドーナツ状のリング体を備え、当該リング体が前記上部接続部で形成される環状体と連環して、当該上部接続部と前記バネ材とを接続することを特徴とする超伝導液面計。 The superconducting liquid level gauge according to claim 2,
A donut-shaped ring body is provided between the upper connection portion and the spring material, and the ring body is connected to an annular body formed by the upper connection portion to connect the upper connection portion and the spring material. Superconducting liquid level gauge characterized by
前記発熱部が、前記収納容器内の上部に取り付けられる接続部の表面に電気抵抗線を巻回して形成されることを特徴とする超伝導液面計。 In the superconducting liquid level gauge according to any one of claims 1 to 3,
The superconducting liquid level gauge, wherein the heat generating portion is formed by winding an electric resistance wire around a surface of a connecting portion attached to an upper portion in the storage container.
前記超伝導線材が、２ホウ化マグネシウム線材、ニオブ３スズ線材、並びにビスマス系、イットリウム系、及び希土類系各酸化物超伝導線材のいずれかであることを特徴とする超伝導液面計。 In the superconducting liquid level gauge according to any one of claims 1 to 4,
A superconducting liquid level gauge, wherein the superconducting wire is any one of a magnesium diboride wire, a niobium 3 tin wire, and bismuth, yttrium, and rare earth oxide superconducting wires.
前記超伝導線材が２ホウ化マグネシウム線材であり、２ホウ化マグネシウムがステンレス鋼のみのシース材で被覆されていることを特徴とする超伝導液面計。 In the superconducting liquid level gauge according to any one of claims 1 to 5,
A superconducting liquid level gauge, wherein the superconducting wire is a magnesium diboride wire, and the magnesium diboride is covered with a sheath material made of only stainless steel.
前記２ホウ化マグネシウム線材の線径が０．１ないし０．２ｍｍであることを特徴とする超伝導液面計。 The superconducting liquid level meter according to claim 6,
A superconducting liquid level gauge characterized in that the magnesium diboride wire has a wire diameter of 0.1 to 0.2 mm.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014076981A1 (en) * | 2012-11-15 | 2014-05-22 | 株式会社東京ワイヤー製作所 | Mgb2-based superconducting wiring material for liquid hydrogen fluid level sensors, liquid hydrogen fluid level sensor, and fluid level meter for liquid hydrogen |
| KR102438523B1 (en) * | 2021-04-19 | 2022-08-31 | 하이리움산업(주) | Level measuring system and method for cryogenic fluid storage tank |
Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56103324A (en) * | 1980-01-21 | 1981-08-18 | Japanese National Railways<Jnr> | Liquid level gauge for cryogenic liquefied gas |
| JPS621125U (en) * | 1985-06-19 | 1987-01-07 | ||
| JPS6225823U (en) * | 1985-07-30 | 1987-02-17 | ||
| JPH06307914A (en) * | 1993-04-26 | 1994-11-04 | Y K K Kk | Liquid helium level gauge |
| JPH07297025A (en) * | 1994-04-28 | 1995-11-10 | Mitsubishi Electric Corp | Oxide superconducting current lead device |
| WO1997008518A1 (en) * | 1995-08-30 | 1997-03-06 | Hitachi, Ltd. | Level gauge using superconductive sensor wire |
| JP2006234391A (en) * | 2005-02-22 | 2006-09-07 | Mitsubishi Heavy Ind Ltd | Liquid level sensor and method of detecting liquid level |
| JP2008532022A (en) * | 2005-03-05 | 2008-08-14 | テヒニッシェ・ウニヴェルジテート・ドレスデン | Superconducting liquid level measuring device for liquefied hydrogen and liquefied neon and measuring method for measuring liquid level |
-
2010
- 2010-03-31 JP JP2010082419A patent/JP2011214951A/en active Pending
Patent Citations (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS56103324A (en) * | 1980-01-21 | 1981-08-18 | Japanese National Railways<Jnr> | Liquid level gauge for cryogenic liquefied gas |
| JPS621125U (en) * | 1985-06-19 | 1987-01-07 | ||
| JPS6225823U (en) * | 1985-07-30 | 1987-02-17 | ||
| JPH06307914A (en) * | 1993-04-26 | 1994-11-04 | Y K K Kk | Liquid helium level gauge |
| JPH07297025A (en) * | 1994-04-28 | 1995-11-10 | Mitsubishi Electric Corp | Oxide superconducting current lead device |
| WO1997008518A1 (en) * | 1995-08-30 | 1997-03-06 | Hitachi, Ltd. | Level gauge using superconductive sensor wire |
| JP2006234391A (en) * | 2005-02-22 | 2006-09-07 | Mitsubishi Heavy Ind Ltd | Liquid level sensor and method of detecting liquid level |
| JP2008532022A (en) * | 2005-03-05 | 2008-08-14 | テヒニッシェ・ウニヴェルジテート・ドレスデン | Superconducting liquid level measuring device for liquefied hydrogen and liquefied neon and measuring method for measuring liquid level |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2014076981A1 (en) * | 2012-11-15 | 2014-05-22 | 株式会社東京ワイヤー製作所 | Mgb2-based superconducting wiring material for liquid hydrogen fluid level sensors, liquid hydrogen fluid level sensor, and fluid level meter for liquid hydrogen |
| US10128024B2 (en) | 2012-11-15 | 2018-11-13 | Tokyo Wire Works, Ltd. | MgB2-based superconducting wire for a liquid hydrogen level sensor, a liquid hydrogen level sensor, and a liquid hydrogen level gauge |
| KR102438523B1 (en) * | 2021-04-19 | 2022-08-31 | 하이리움산업(주) | Level measuring system and method for cryogenic fluid storage tank |
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