JP2005005574A - Superconductive electromagnet device - Google Patents

Superconductive electromagnet device Download PDF

Info

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
Authority
JP
Japan
Prior art keywords
liquid level
level gauge
liquid
terminal
low temperature
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
Application number
JP2003169118A
Other languages
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
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mitsubishi Electric Corp
Original Assignee
Mitsubishi Electric Corp
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Mitsubishi Electric Corp filed Critical Mitsubishi Electric Corp
Priority to JP2003169118A priority Critical patent/JP2005005574A/en
Publication of JP2005005574A publication Critical patent/JP2005005574A/en
Pending legal-status Critical Current

Links

Images

Landscapes

  • Containers, Films, And Cooling For Superconductive Devices (AREA)

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)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP2003169118A JP2005005574A (en) 2003-06-13 2003-06-13 Superconductive electromagnet device

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP2003169118A JP2005005574A (en) 2003-06-13 2003-06-13 Superconductive electromagnet device

Publications (1)

Publication Number Publication Date
JP2005005574A true JP2005005574A (en) 2005-01-06

Family

ID=34094353

Family Applications (1)

Application Number Title Priority Date Filing Date
JP2003169118A Pending JP2005005574A (en) 2003-06-13 2003-06-13 Superconductive electromagnet device

Country Status (1)

Country Link
JP (1) JP2005005574A (en)

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

Similar Documents

Publication Publication Date Title
US5936498A (en) Superconducting magnet apparatus and magnetic resonance imaging system using the same
US8554294B2 (en) Low-noise cooling apparatus
US8350568B2 (en) Nuclear magnetic resonance apparatus
Witt Electrical resistance standards and the quantum Hall effect
Wu et al. Design and testing of a high temperature superconducting current lead
CN115113126B (en) Device and method for testing and calibrating metal Hall probe
US7762132B2 (en) Refrigerant liquid level measuring device, refrigerant liquid level measuring method, and superconducting magnet device
Goodrich et al. Magnetoresistance below 1 K and temperature cycling of ruthenium oxide–bismuth ruthenate cryogenic thermometers
Seton et al. Liquid helium cryostat for SQUID-based MRI receivers
JP2005005574A (en) Superconductive electromagnet device
JPH06174753A (en) High current detector
Ogawa et al. Influence of transport current distribution on AC transport current loss measurement in an assembled conductor
JP3977105B2 (en) Open magnetic resonance imaging system
Schmidt Calorimetric ac-loss measurement of high Tc-tapes at 77 K, a new measuring technique
Kose Recent advances in Josephson voltage standards
Goodrich et al. Kiloampere, variable-temperature, critical-current measurements of high-field superconductors
Scott et al. Use of a magnetoresistor to measure the magnetic field in a superconducting magnet
KR20170074248A (en) Magnetic levitation force measuring device of superconductor for education
Schmidt Temperature-dependent AC loss and time constant measurements in high-Tc superconductors
JP4369774B2 (en) Magnetic resonance imaging device using superconducting magnet device
RU208875U1 (en) Installation for recording the magnetic properties of high-temperature superconductors in a wide range of temperatures and magnetic fields in a continuous mode
Pei et al. The I $ _ {\rm c} $ Behavior of 2G YBCO Tapes Under DC/AC Magnetic Fields at Various Temperatures
JP2658140B2 (en) Liquid level measurement method and apparatus
Sachslehner et al. Two-channel DC-SQUID picovoltmeter for the measurement of low-field Hall coefficient and electrical resistance from 4.2 to 100 K
Lonzarich et al. Temperature dependence of the Fermi surface of gold

Legal Events

Date Code Title Description
A621 Written request for application examination

Free format text: JAPANESE INTERMEDIATE CODE: A621

Effective date: 20050428

A977 Report on retrieval

Free format text: JAPANESE INTERMEDIATE CODE: A971007

Effective date: 20070420

A131 Notification of reasons for refusal

Free format text: JAPANESE INTERMEDIATE CODE: A131

Effective date: 20070904

A02 Decision of refusal

Free format text: JAPANESE INTERMEDIATE CODE: A02

Effective date: 20080108