JP2005005574A - Superconductive electromagnet device - Google Patents

Superconductive electromagnet device Download PDF

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Publication number
JP2005005574A
JP2005005574A JP2003169118A JP2003169118A JP2005005574A JP 2005005574 A JP2005005574 A JP 2005005574A JP 2003169118 A JP2003169118 A JP 2003169118A JP 2003169118 A JP2003169118 A JP 2003169118A JP 2005005574 A JP2005005574 A JP 2005005574A
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JP
Japan
Prior art keywords
liquid level
level gauge
liquid
terminal
low temperature
Prior art date
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Pending
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JP2003169118A
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Japanese (ja)
Inventor
Shuichi Nakagawa
修一 中川
Naoharu Yoshida
直治 吉田
Takahiro Matsumoto
隆博 松本
Akihiko Ariyoshi
昭彦 有吉
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Mitsubishi Electric Corp
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Mitsubishi Electric Corp
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Publication date
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Priority to JP2003169118A priority Critical patent/JP2005005574A/en
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Abstract

<P>PROBLEM TO BE SOLVED: To obtain an economical superconductive electromagnet device in which the quantity of heat entering an extremely low temperature part is reduced as a whole and the consumption of a cooling medium is reduced, by reducing the number of wires from a room temperature part which is the outside of a low temperature container up to the extremely low temperature part in the container and selecting a material of the wires. <P>SOLUTION: The superconductive electromagnetic device is obtained by arranging two superconductive magnets each of which stores a superconductive coil and a liquid-level meter in a low temperature container filled with a cooling medium on upper and lower positions at prescribed intervals. Each liquid-level meter is provided with a current terminal connected to a current source and a voltage terminal connected to a voltmeter, the minus pole of the current terminal of the liquid-level meter for the upper low temperature container is connected to the plus pole of the current terminal of the liquid-level meter for the lower low temperature container in series, and the minus pole of the voltage terminal of the liquid-level meter for the upper low temperature container is connected to the plus pole of the voltage terminal of the liquid-level meter for the lower low temperature container in common. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

【0001】
【発明の属する技術分野】
この発明は、超電導電磁石装置に関し、特に超電導電磁石の液面計測装置の改良に関するものである。
【0002】
【従来の技術】
例えば、医療用の断層撮像装置(MRI装置)の静磁場発生源として使用される超電導電磁石装置においては、超電導電磁石を冷却している液体ヘリウムや液体窒素等の冷媒液面を計測する液面計測装置が必要である。
【0003】
この液面計測装置として、例えば液体ヘリウム液面計と呼ばれるものが使用されている。図4はこの液体ヘリウム液面計の構成を示す概略図であり、液体ヘリウム1の沸点に近い温度で超電導特性を示す超伝導線2が液面高さ検出素子として使用され、この超伝導線2の両端には電圧端子が設けられ、電圧計3が接続されている。
また、超伝導線2の両端部には電流端子が設けられ、超伝導線2の上部電流端子側には超伝導線2を加熱するヒータ4が接続され、ヒータ4は電流源5を介して超伝導線2の下部電流端子に接続されている。
【0004】
このような液体ヘリウム液面計においては、電流源5から超伝導線2とヒータ4に電流を流すと、超伝導線2の内、液体ヘリウム1の液面から下部は超電導状態であるが、液面から上部は温度が上がり常伝導状態となって超伝導線2に抵抗が発生する。この抵抗によって発生する電圧を電圧計3で検出し、超伝導線2の常伝導部分の電気抵抗を測定することにより、液体ヘリウムの液面高さを測定することができる。
【0005】
図5は上記液体ヘリウム液面計を開放型超電導電磁石装置に適用した状態を示す断面模式図である。開放型超電導電磁石装置とは、上下に二個の超電導電磁石を所定の間隔で対抗配置したもので、広い開口部を有し、患者の開放感や検査技師の患者へのアクセス性を必要とするMRI装置用電磁石に特に普及しているタイプのものである。
【0006】
図5において、上部真空断熱容器6と下部真空断熱容器7が所定の間隔で上下に対向配置され真空容器連結管8で連結されている。上部真空断熱容器6内には上部低温容器9が、また下部真空断熱容器7には下部低温容器10がそれぞれ収容され、上部低温容器9と下部低温容器10とは低温連結管11で連結されている。
更に、上部低温容器9内には上部超電導コイル12と上部低温容器用液面計13とが収容されており、また下部低温容器10内には下部超電導コイル14と下部低温容器用液面計15とがそれぞれ収容されている。
【0007】
最後に、上記上部低温容器用液面計13と下部低温容器用液面計14の+極とー極両端にはそれぞれ電流通電線16を介して電流源17が接続されており、更に電圧測定線18を介して電圧計19が接続されている。
従来の開放型超電導電磁石装置は上述のように構成されていたため、一つの液面計に対して必要とする線の数量は4本、合計8本必要としていた。
【0008】
一方、図6は従来の水平型円筒ソレノイド型超電導電磁石装置に上記液体ヘリウム液面計を2系統適用した状態を示す断面模式図である。
通常、液体ヘリウム液面計には、熱入力を小さくし同一液面変化で大きな抵抗変化をもたらすために、非常に細い超電導線2(図4)が使用されており、万一断線事故等の異常が発生した場合には液面測定が出来なくなるため、液面計を2系統設置する場合が多い。
【0009】
図中、液体ヘリウム1を収容した低温容器21内に、円筒ソレノイド型超電導コイル22及び2系統の液面計23,24が浸漬されている。
図5と同一符号は相当部分を示しており、液面計23,24は図4に示したものと同一構造である。この場合も一つの液面計に対して必要とする線の数量は4本、合計8本必要としていた。
【0010】
【発明が解決しようとする課題】
ところが、このように液面計設置に不可欠な電流通電線16や電圧測定線18を介して低温容器の外部の常温部から内部の極低温部に侵入する熱量は少なくなく、このため液体ヘリウムの消費量が増加するという問題があった。
この発明は上記問題を解決するためになされたもので、低温容器の外部の常温部から内部の極低温部までの配線数を減らし、また配線材料を選択することにより、極低温部に侵入する熱量を全体として低減し、消費冷媒量を減少させた経済的な超電導電磁石装置を提供するものである。
【0011】
【課題を解決するための手段】
本発明は、冷媒を充填した低温容器内に超電導コイルおよび液面計を収納した超電導電磁石2個を上下に所定の間隔で配置した超電導電磁石装置において、それぞれの液面計は電流源に接続された電流端子と電圧計に接続された電圧端子を備え、上部低温容器用液面計の電流端子の−極と下部低温容器用液面計の電流端子の+極とを直列接続し、上部低温容器用液面計の電圧端子の−極と下部低温容器用液面計の電圧端子の+極とを共通接続したことを特徴とするものである。
【0012】
本発明はまた、冷媒を充填した低温容器内に超電導コイルおよび少なくとも2個の液面計を収納した超電導電磁石装置において、それぞれの液面計は電流源に接続された電流端子と電圧計に接続された電圧端子を備え、一方の液面計の−極電流端子と他方の液面計の−極電流端子とを共通接続し、一方の液面計の−極電圧端子と他方の液面計の−極電圧端子とを共通接続したことを特徴とするものである。
【0013】
本発明は更に上述した超電導電磁石装置において、前記電流源に接続される電流通電線及び前記電圧計に接続される電圧測定線の材料にリン脱酸銅を使用したことを特徴とするものである。
【0014】
実施の形態1.
次に本発明の実施の形態について図に従って説明する。
図1は本発明の実施の形態1を示しており、上記した図5の従来装置に対応する開放型超電導電磁石装置に適用した状態を示す断面模式図である。
図中、図5と同一符号は同一または相当部分を示している。図5と異なる点は上部低温容器用液面計13及び下部低温容器用液面計15の電流源17及び電圧計19への接続配線のみである。
【0015】
すなわち、上部低温容器用液面計13の電流端子の−極と下部低温容器用液面計15の電流端子の+極を直列接続し、更に上部低温容器用液面計13の電圧端子の−極と下部低温容器用液面計15の電圧端子の+極を共通接続したものである。
こうすることにより、2本の電流通電線16で電流源17から上下の液面計13,15に同時に通電することができ、また、3本の電圧測定線18で上下液面計13,15それぞれの電圧測定が可能となり、必要とされる線数を合計5本とすることができる。
【0016】
上述のように実施の形態1によれば、上下に2個の超電導電磁石を所定の間隔で対抗配置した開放型超電導電磁石装置であっても、上部低温容器用液面計13及び下部低温容器用液面計15の電流源17及び電圧計19への接続配線を、従来の8本から5本に減少させることが出来、低温容器の外部常温部から内部低温部へ侵入する熱量を低減させることが出来る。
【0017】
実施の形態2.
図2は本発明の実施の形態2を示しており、従来の図6に対応する水平型円筒ソレノイド型超電導電磁石装置に適用した状態を示す断面模式図である。
図中、図6と同一符号は同一または相当部分を示している。図6と異なる点は低温容器用液面計23及び24の電流源17及び電圧計19との接続配線のみである。
すなわち、一方の低温容器用液面計23の−極電流端子と他方の低温容器用液面計24の−極電流端子とを共通接続し、更に一方の低温容器用液面計23の−極電圧端子と他方の低温容器用液面計24の−極電圧端子とを共通接続したものである。
【0018】
こうすることにより、3本の電流通電線16で電流源17、17から2つの液面計23,24にそれぞれ通電することができ、また、3本の電圧測定線18で液面計23,24それぞれの電圧測定が可能となり、必要とされる線数を合計6本とすることができる。
【0019】
上述のように実施の形態2によれば、液体ヘリウム液面計を2系統適用した超電導電磁石装置であっても、低温容器用液面計23及び24の電流源17及び電圧計19への接続配線を、従来の8本から6本に減少させることが出来、低温容器の外部常温部から内部低温部へ侵入する熱量を低減させることが出来る。
なお、本実施形態は3本以上の液面計が設置されている場合も同様に適用できるものである。
【0020】
実施の形態3.
実施の形態3は、電流通電線16及び電圧測定線18に使用される材料を改善することにより熱量侵入を抑制するものである。
すなわち、電流通電線16及び電圧測定線18には、従来、液面測定を正確に行うため電気抵抗の少ない銅線が使用されているが、銅線は熱伝導率が高いため常温部からの熱侵入量が大きい。
【0021】
実施の形態3はこの銅線の材料としてリン脱酸銅を使用したものである。リン脱酸銅は300K(ケルビン)と6K(ケルビン)の温度差における熱侵入量が電気銅を1とした場合、0.275と電気銅の1/3以下となる性質があるため、熱侵入量の低減に大いに効果がある。
図3は電気銅とリン脱酸銅の300Kと6Kの温度差における熱侵入量の比を示す図表である。
【0022】
【発明の効果】
以上説明したように、この発明によれば、低温容器の外部の常温部から内部の極低温部までの配線数を減らすことにより、液面計を通して極低温部に侵入する熱量を全体として低減し、消費冷媒量を減少させた経済的な超電導電磁石装置が実現できる。
【図面の簡単な説明】
【図1】本発明の実施の形態1を示す液体ヘリウム液面計を開放型超電導電磁石装置に適用した状態を示す断面模式図である。
【図2】本発明の実施の形態2を示す液体ヘリウム液面計を水平型円筒ソレノイド型超電導電磁石装置に適用した状態を示す断面模式図である。
【図3】電気銅とリン脱酸銅の300Kと6Kの温度差における熱侵入量の比を示す図表である。
【図4】液体ヘリウム液面計の構成を示す概略図である。
【図5】図4の液体ヘリウム液面計を開放型超電導電磁石装置に適用した従来の状態を示す断面模式図である。
【図6】図4の液体ヘリウム液面計を水平型円筒ソレノイド型超電導電磁石装置に2系統適用した従来の状態を示す断面模式図である。
【符号の説明】
1 液体ヘリウム、2 超電導線、9 上部低温容器、10 下部低温容器、22 超電導コイル、13 上部低温容器用液面計、15 下部低温容器用液面計、16 電流通電線、17 電流源、18 電圧測定線、19 電圧計、21低温容器、23,24 液面計。
[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a superconducting electromagnet apparatus, and more particularly to improvement of a liquid level measuring apparatus for a superconducting electromagnet.
[0002]
[Prior art]
For example, in a superconducting electromagnet apparatus used as a static magnetic field generation source of a medical tomographic imaging apparatus (MRI apparatus), liquid level measurement for measuring the liquid level of liquid helium, liquid nitrogen or the like that cools the superconducting electromagnet Equipment is needed.
[0003]
As this liquid level measuring device, for example, a so-called liquid helium level gauge is used. FIG. 4 is a schematic diagram showing the configuration of the liquid helium level gauge. A superconducting wire 2 that exhibits superconducting characteristics at a temperature close to the boiling point of the liquid helium 1 is used as a liquid level detecting element. Voltage terminals are provided at both ends of 2, and a voltmeter 3 is connected.
Further, current terminals are provided at both ends of the superconducting wire 2, and a heater 4 for heating the superconducting wire 2 is connected to the upper current terminal side of the superconducting wire 2, and the heater 4 is connected via a current source 5. It is connected to the lower current terminal of the superconducting wire 2.
[0004]
In such a liquid helium level gauge, when a current is passed from the current source 5 to the superconducting wire 2 and the heater 4, the superconducting wire 2 is superconducting from the liquid helium 1 to the bottom. The temperature rises from the liquid level to the normal state and a resistance is generated in the superconducting wire 2. By detecting the voltage generated by this resistance with the voltmeter 3 and measuring the electrical resistance of the normal conduction part of the superconducting wire 2, the liquid level of liquid helium can be measured.
[0005]
FIG. 5 is a schematic cross-sectional view showing a state in which the liquid helium level gauge is applied to an open superconducting electromagnet apparatus. An open-type superconducting electromagnet device is a superconducting magnet with two superconducting magnets arranged on the top and bottom at a predetermined interval, has a wide opening, and requires a patient's sense of openness and accessibility to the patient by a laboratory technician This type is particularly popular for electromagnets for MRI apparatuses.
[0006]
In FIG. 5, an upper vacuum heat insulating container 6 and a lower vacuum heat insulating container 7 are vertically opposed to each other at a predetermined interval and are connected by a vacuum container connecting pipe 8. An upper cryogenic container 9 is accommodated in the upper vacuum insulated container 6, and a lower cryogenic container 10 is accommodated in the lower vacuum insulated container 7, and the upper cryogenic container 9 and the lower cryogenic container 10 are coupled by a cryogenic connection pipe 11. Yes.
Further, an upper superconducting coil 12 and an upper cryogenic vessel liquid level gauge 13 are accommodated in the upper cryogenic container 9, and a lower superconducting coil 14 and a lower cryogenic container liquid level gauge 15 are contained in the lower cryogenic container 10. And are housed respectively.
[0007]
Finally, a current source 17 is connected to both ends of the upper and lower cryogenic vessel liquid level gauges 13 and 14 via current conducting wires 16 at both ends of the positive and negative poles, respectively. A voltmeter 19 is connected via a line 18.
Since the conventional open superconducting electromagnet apparatus is configured as described above, the number of wires required for one liquid level gauge is four, that is, a total of eight lines are required.
[0008]
On the other hand, FIG. 6 is a schematic cross-sectional view showing a state in which two systems of the liquid helium level gauge are applied to a conventional horizontal cylindrical solenoid superconducting electromagnet apparatus.
Usually, a very thin superconducting wire 2 (Fig. 4) is used in a liquid helium level gauge to reduce the heat input and bring about a large resistance change with the same liquid level change. If an abnormality occurs, the liquid level cannot be measured, so two liquid level gauges are often installed.
[0009]
In the figure, a cylindrical solenoid type superconducting coil 22 and two systems of liquid level gauges 23 and 24 are immersed in a cryogenic container 21 containing liquid helium 1.
The same reference numerals as those in FIG. 5 indicate corresponding parts, and the liquid level gauges 23 and 24 have the same structure as that shown in FIG. In this case as well, the number of lines required for one liquid level gauge is four, which is a total of eight.
[0010]
[Problems to be solved by the invention]
However, the amount of heat entering the cryogenic part from the outside of the cryogenic vessel through the current conducting line 16 and the voltage measuring line 18 that are indispensable for installing the level gauge is not small. There was a problem that consumption increased.
The present invention has been made to solve the above-mentioned problem. By reducing the number of wires from the outside normal temperature portion of the cryogenic container to the inside cryogenic portion and selecting the wiring material, the intrusion into the cryogenic portion is achieved. The present invention provides an economical superconducting electromagnet apparatus in which the amount of heat is reduced as a whole and the amount of refrigerant consumed is reduced.
[0011]
[Means for Solving the Problems]
The present invention relates to a superconducting electromagnet apparatus in which two superconducting electromagnets, each containing a superconducting coil and a liquid level gauge, are arranged at predetermined intervals in a cryogenic container filled with a refrigerant. Each liquid level gauge is connected to a current source. The current terminal and the voltage terminal connected to the voltmeter are connected in series, and the negative terminal of the current terminal of the liquid level gauge for the upper cryogenic container and the positive electrode of the current terminal of the liquid level gauge for the lower cryogenic container are connected in series, The negative terminal of the voltage terminal of the liquid level gauge for containers and the positive electrode of the voltage terminal of the liquid level gauge for lower cryogenic containers are connected in common.
[0012]
The present invention also provides a superconducting electromagnet apparatus in which a superconducting coil and at least two liquid level gauges are housed in a cryogenic container filled with a refrigerant, wherein each liquid level gauge is connected to a current terminal and a voltmeter connected to a current source. A negative electrode terminal of one liquid level gauge and a negative electrode terminal of the other liquid level gauge, and a negative electrode terminal of one liquid level gauge and the other liquid level gauge. The negative electrode voltage terminal is commonly connected.
[0013]
In the superconducting electromagnet apparatus described above, the present invention is characterized in that phosphorous deoxidized copper is used as a material for a current conducting line connected to the current source and a voltage measuring line connected to the voltmeter. .
[0014]
Embodiment 1 FIG.
Next, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows a first embodiment of the present invention, and is a schematic cross-sectional view showing a state where it is applied to an open superconducting electromagnet apparatus corresponding to the above-described conventional apparatus of FIG.
In the figure, the same reference numerals as those in FIG. 5 denote the same or corresponding parts. The only difference from FIG. 5 is the connection wiring to the current source 17 and the voltmeter 19 of the liquid level gauge 13 for the upper cryogenic container and the liquid level gauge 15 for the lower cryogenic container.
[0015]
That is, the negative terminal of the current terminal of the liquid level gauge for the upper cryogenic container 13 and the positive electrode of the current terminal of the liquid level gauge for the lower cryogenic container 15 are connected in series, and the voltage terminal of the liquid level gauge for the upper cryogenic container is further − The positive electrode and the positive electrode of the voltage terminal of the lower cryogenic vessel liquid level gauge 15 are connected in common.
By doing so, it is possible to energize the upper and lower liquid level gauges 13 and 15 simultaneously from the current source 17 with the two current conducting lines 16, and the upper and lower liquid level gauges 13 and 15 with the three voltage measuring lines 18. Each voltage can be measured, and the total number of lines required can be five.
[0016]
As described above, according to the first embodiment, even in the open type superconducting electromagnet apparatus in which two superconducting magnets are arranged on the upper and lower sides at a predetermined interval, the liquid level gauge 13 for the upper cryogenic container and the lower cryogenic container are used. The connection wiring to the current source 17 and the voltmeter 19 of the liquid level gauge 15 can be reduced from the conventional eight to five, and the amount of heat entering the internal low temperature part from the external normal temperature part of the low temperature container can be reduced. I can do it.
[0017]
Embodiment 2. FIG.
FIG. 2 shows a second embodiment of the present invention, and is a schematic cross-sectional view showing a state applied to a conventional horizontal cylindrical solenoid superconducting electromagnet apparatus corresponding to FIG.
In the figure, the same reference numerals as those in FIG. 6 denote the same or corresponding parts. The only difference from FIG. 6 is the connection wiring between the current source 17 and the voltmeter 19 of the liquid level gauges 23 and 24 for cryogenic containers.
That is, the negative electrode terminal of one cryogenic vessel liquid level gauge 23 and the negative electrode terminal of the other cryogenic container liquid level gauge 24 are connected in common, and the negative electrode of one cryogenic container liquid level gauge 23 is connected. The voltage terminal and the negative electrode terminal of the liquid level gauge 24 for the other cryogenic container are connected in common.
[0018]
By doing so, it is possible to energize the two liquid level gauges 23 and 24 from the current sources 17 and 17 with the three current conducting lines 16, respectively, and the liquid level gauges 23 and 24 with the three voltage measuring lines 18. Each of the 24 voltages can be measured, and the total number of lines required can be six.
[0019]
As described above, according to the second embodiment, even in a superconducting electromagnet apparatus to which two liquid helium level gauges are applied, connection to the current source 17 and the voltmeter 19 of the liquid level gauges 23 and 24 for cryogenic containers is performed. The number of wires can be reduced from the conventional 8 to 6, and the amount of heat entering the internal low temperature portion from the external normal temperature portion of the low temperature container can be reduced.
In addition, this embodiment can be similarly applied when three or more liquid level meters are installed.
[0020]
Embodiment 3 FIG.
In Embodiment 3, the material used for the current conducting wire 16 and the voltage measuring wire 18 is improved to suppress the intrusion of heat.
That is, for the current conducting line 16 and the voltage measuring line 18, conventionally, a copper wire with low electrical resistance is used to accurately measure the liquid level. However, since the copper wire has high thermal conductivity, Large amount of heat penetration.
[0021]
Embodiment 3 uses phosphorous deoxidized copper as the material of the copper wire. Phosphorus deoxidized copper has the property that the amount of heat penetration at a temperature difference between 300K (Kelvin) and 6K (Kelvin) is 0.275, which is 1/3 or less of that of copper, so that heat penetration. It is very effective in reducing the amount.
FIG. 3 is a chart showing the ratio of the heat penetration amount in the temperature difference between 300 K and 6 K between electrolytic copper and phosphorous deoxidized copper.
[0022]
【The invention's effect】
As described above, according to the present invention, the amount of heat entering the cryogenic part through the liquid level gauge is reduced as a whole by reducing the number of wires from the ordinary temperature part outside the cryogenic container to the inside cryogenic part. Thus, an economical superconducting electromagnet apparatus with reduced refrigerant consumption can be realized.
[Brief description of the drawings]
FIG. 1 is a schematic cross-sectional view showing a state in which a liquid helium level gauge according to Embodiment 1 of the present invention is applied to an open superconducting electromagnet apparatus.
FIG. 2 is a schematic cross-sectional view showing a state in which the liquid helium level gauge according to the second embodiment of the present invention is applied to a horizontal cylindrical solenoid superconducting electromagnet apparatus.
FIG. 3 is a chart showing a ratio of heat penetration amounts in the temperature difference between 300 K and 6 K between electrolytic copper and phosphorous deoxidized copper.
FIG. 4 is a schematic diagram showing the configuration of a liquid helium level gauge.
5 is a schematic cross-sectional view showing a conventional state in which the liquid helium level gauge of FIG. 4 is applied to an open superconducting electromagnet apparatus.
6 is a schematic cross-sectional view showing a conventional state in which two systems of the liquid helium level gauge shown in FIG. 4 are applied to a horizontal cylindrical solenoid superconducting electromagnet apparatus.
[Explanation of symbols]
1 liquid helium, 2 superconducting wire, 9 upper cryogenic container, 10 lower cryogenic container, 22 superconducting coil, 13 liquid level gauge for upper cryogenic container, 15 liquid level gauge for lower cryogenic container, 16 current conducting wire, 17 current source, 18 Voltage measurement line, 19 Voltmeter, 21 Cryogenic container, 23, 24 Liquid level gauge.

Claims (3)

冷媒を充填した低温容器内に超電導コイルおよび液面計を収納した超電導電磁石を、上下に2個所定の間隔で配置した超電導電磁石装置において、それぞれの液面計は電流源に接続された電流端子と電圧計に接続された電圧端子を備え、前記上部低温容器用液面計の電流端子の−極と下部低温容器用液面計の電流端子の+極とを直列接続し、上部低温容器用液面計の電圧端子の−極と下部低温容器用液面計の電圧端子の+極とを共通接続したことを特徴とする超電導電磁石装置。In a superconducting electromagnet apparatus in which two superconducting electromagnets each containing a superconducting coil and a liquid level gauge are arranged at predetermined intervals in a cryogenic container filled with a refrigerant, each liquid level gauge is a current terminal connected to a current source. And a voltage terminal connected to the voltmeter, the negative terminal of the current terminal of the liquid level gauge for the upper cryogenic container and the positive electrode of the current terminal of the liquid level gauge for the lower cryogenic container are connected in series, for the upper cryogenic container A superconducting electromagnet apparatus characterized in that a negative pole of a voltage terminal of a liquid level gauge and a positive pole of a voltage terminal of a liquid level gauge for a lower cryogenic container are connected in common. 冷媒を充填した低温容器内に超電導コイルおよび少なくとも2個の液面計を収納した超電導電磁石装置において、それぞれの液面計は電流源に接続された電流端子と電圧計に接続された電圧端子を備え、一方の液面計の−極電流端子と他方の液面計の−極電流端子とを共通接続し、一方の液面計の−極電圧端子と他方の液面計の−極電圧端子とを共通接続したことを特徴とする超電導電磁石装置。In a superconducting electromagnet apparatus in which a superconducting coil and at least two liquid level gauges are housed in a cryogenic container filled with a refrigerant, each liquid level gauge has a current terminal connected to a current source and a voltage terminal connected to a voltmeter. The-pole current terminal of one liquid level gauge and the-pole current terminal of the other liquid level gauge are connected in common, the-pole voltage terminal of one liquid level gauge and the-pole voltage terminal of the other liquid level gauge And a superconducting electromagnet apparatus characterized by being connected in common. 上記請求項1あるいは請求項2の超電導電磁石装置において、前記電流源に接続される電流通電線及び前記電圧計に接続される電圧測定線の材料にリン脱酸銅を使用したことを特徴とする超電導電磁石装置。In the superconducting electromagnet apparatus according to claim 1 or 2, phosphorous deoxidized copper is used as a material for a current conducting wire connected to the current source and a voltage measuring wire connected to the voltmeter. Superconducting electromagnet device.
JP2003169118A 2003-06-13 2003-06-13 Superconductive electromagnet device Pending JP2005005574A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007060950A1 (en) * 2005-11-25 2007-05-31 Hitachi Medical Corporation Mri system employing superconducting magnet and its maintenance method

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2007060950A1 (en) * 2005-11-25 2007-05-31 Hitachi Medical Corporation Mri system employing superconducting magnet and its maintenance method
US7996117B2 (en) 2005-11-25 2011-08-09 Hitachi Medical Corporation MRI system employing superconducting magnet and its maintenance method
JP5004805B2 (en) * 2005-11-25 2012-08-22 株式会社日立メディコ MRI apparatus using superconducting magnet and its maintenance method

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