JP3260497B2 - Superconducting magnet for MRI equipment - Google Patents
Superconducting magnet for MRI equipmentInfo
- Publication number
- JP3260497B2 JP3260497B2 JP18485893A JP18485893A JP3260497B2 JP 3260497 B2 JP3260497 B2 JP 3260497B2 JP 18485893 A JP18485893 A JP 18485893A JP 18485893 A JP18485893 A JP 18485893A JP 3260497 B2 JP3260497 B2 JP 3260497B2
- Authority
- JP
- Japan
- Prior art keywords
- radiation shield
- superconducting magnet
- heat
- plate
- refrigerator
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Lifetime
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- Magnetic Resonance Imaging Apparatus (AREA)
Description
【０００１】[0001]
【産業上の利用分野】本発明は、冷凍機により輻射シー
ルドを冷却してなるＭＲＩ装置用の超電導磁石に係り、
特に輻射シールドの温度を下げて液体ヘリウムの消費量
を低減すると共に、良好なＭＲＩ画像が得られるように
した小形でかつ安価なＭＲＩ装置用超電導磁石に関する
ものである。BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a superconducting magnet for an MRI apparatus in which a radiation shield is cooled by a refrigerator.
In particular, the present invention relates to a small and inexpensive superconducting magnet for an MRI apparatus capable of lowering the temperature of a radiation shield to reduce the consumption of liquid helium and obtaining a good MRI image.
【０００２】[0002]
【従来の技術】図５は、この種の従来のＭＲＩ装置用超
電導磁石の全体組立構成例を示す断面図である。図５に
おいて、ＭＲＩ装置用超電導磁石は、真空容器１と、真
空容器１の内部に収納された第１の輻射シールド２ａ、
第２の輻射シールド２ｂ、およびヘリウム容器３と、ヘ
リウム容器３の内部に収納された超電導コイル４と、真
空容器１の外部に設置された冷凍機５と、冷凍機５と第
１の輻射シールド２ａおよび第２の輻射シールド２ｂと
をそれぞれ結合する第１の伝熱板６ａおよび第２の伝熱
板６ｂと、ヘリウム容器３の内部に収容された液体ヘリ
ウム７とから構成されている。2. Description of the Related Art FIG. 5 is a cross-sectional view showing an example of the overall assembly of a conventional superconducting magnet for an MRI apparatus of this kind. In FIG. 5, a superconducting magnet for an MRI apparatus includes a vacuum vessel 1, a first radiation shield 2a housed inside the vacuum vessel 1,
A second radiation shield 2b, a helium container 3, a superconducting coil 4 housed inside the helium container 3, a refrigerator 5 installed outside the vacuum container 1, a refrigerator 5 and the first radiation shield The helium container 3 includes a first heat transfer plate 6a and a second heat transfer plate 6b for connecting the second radiation shield 2b and the second radiation shield 2b, respectively, and a liquid helium 7 accommodated in the helium container 3.
【０００３】第１の輻射シールド２ａおよび第２の輻射
シールド２ｂは、冷凍機５と、第１の伝熱板６ａおよび
第２の伝熱板６ｂを介して熱的結合がなされており、冷
却されている。[0003] The first radiation shield 2a and the second radiation shield 2b are thermally coupled to the refrigerator 5 through the first heat transfer plate 6a and the second heat transfer plate 6b. Have been.
【０００４】すなわち、各輻射シールド２ａ，２ｂの定
常温度は、第１の輻射シールド２ａが６０k 〜８０k 、
第２の輻射シールド２ｂが１５k 〜２０k に冷却され
る。しかしながら、このようなＭＲＩ装置用超電導磁石
では、液体ヘリウム７の消費量が０．０２ｌ／ｈ以上と
なり、液体ヘリウム７の消費量と液体ヘリウム７の注液
間隔の低減化、および超電導磁石のコンパクト化を図る
上で、大きな支障となっている。That is, the steady temperature of each of the radiation shields 2a and 2b is 60 k to 80 k for the first radiation shield 2 a,
Second radiation shield 2b is cooled to 15 k to 20 k. However, in such a superconducting magnet for an MRI apparatus, the consumption of the liquid helium 7 is 0.02 l / h or more, the consumption of the liquid helium 7 and the injection interval of the liquid helium 7 are reduced, and the superconducting magnet is compact. This has been a major obstacle in achieving the goal.
【０００５】[0005]
【発明が解決しようとする課題】以上のように、従来の
ＭＲＩ装置用超電導磁石においては、液体ヘリウムの消
費量が多いばかりでなく、超電導磁石のコンパクト化を
図れないという問題があった。As described above, the conventional superconducting magnet for an MRI apparatus not only consumes a large amount of liquid helium but also has a problem that the superconducting magnet cannot be made compact.
【０００６】本発明の目的は、輻射シールドの温度を下
げて液体ヘリウムの消費量を低減すると共に、良好なＭ
ＲＩ画像を得ることが可能な小形でかつ安価なＭＲＩ装
置用超電導磁石を提供することにある。[0006] It is an object of the present invention to reduce the temperature of the radiation shield to reduce the consumption of liquid helium and to obtain a good M
An object of the present invention is to provide a small and inexpensive superconducting magnet for an MRI apparatus capable of obtaining an RI image.
【０００７】[0007]
【課題を解決するための手段】上記の目的を達成するた
めに本発明では、冷凍機により輻射シールドを冷却して
なるＭＲＩ装置用超電導磁石において、上記冷凍機に、
蓄冷材の材質としてＥｒ3 Ｎｉ合金等の磁性材料を用い
ると共に、上記輻射シールドとして、純度９９．９９％
以上の高純度アルミニウム材からなる熱伝導板を設けた
輻射シールドを備え、上記熱伝導板として、冷凍機との
結合部または熱集中部から、軸方向および円周方向に軸
熱伝導板および周熱伝導板を設けるようにしている。In order to achieve the above object, the present invention provides a superconducting magnet for an MRI apparatus in which a radiation shield is cooled by a refrigerator.
A magnetic material such as an Er 3 Ni alloy is used as the material of the cold storage material, and the radiation shield has a purity of 99.99%.
Comprises a radiation shield having a heat conductive plate having the above high-purity aluminum material, as the heat conducting plate, the refrigerator
Axial and circumferential directions from joints or heat concentrators
A heat conduction plate and a peripheral heat conduction plate are provided.
【０００８】ここで、特に上記軸熱伝導板を円周方向に
対称位置に取付けると共に、上記周熱伝導板を軸方向に
対称位置に取付けるようにしている。 Here, in particular, the shaft heat conducting plate is arranged in a circumferential direction.
Attach it in a symmetrical position and attach
They are installed in symmetrical positions.
【０００９】[0009]
【作用】従って、本発明のＭＲＩ装置用超電導磁石にお
いては、冷凍機には、蓄冷材の材質としてＥｒ3 Ｎｉ合
金等の磁性材料を用いて、冷凍機の到達温度を下げると
共に、輻射シールドには、純度９９．９９％以上の高純
度アルミニウム材からなる軸熱伝導板および周熱伝導板
を、冷凍機との結合部または熱集中部から、軸方向およ
び円周方向に設けることにより、輻射シールド温度は１
０k 以下にすることが可能となるため、ＭＲＩ画像が良
好で、かつクエンチ時の機械的強度もあり、液体ヘリウ
ムの消費量を低減することができる。さらに、特に円周
方向に１枚の板で周熱伝導板を設けることにより 、 機械
的強度も良好であり、機械的破損、変形を防止すること
ができる。 Therefore, in the superconducting magnet for an MRI apparatus of the present invention, a magnetic material such as an Er 3 Ni alloy is used as a material of the regenerator material for the refrigerator to lower the temperature reached by the refrigerator and to provide a radiation shield. Is to provide a shaft heat conduction plate and a peripheral heat conduction plate made of a high-purity aluminum material having a purity of 99.99% or more in an axial direction and a circumferential direction from a coupling portion with a refrigerator or a heat concentration portion. Therefore, the radiation shield temperature is 1
Since it can be set to 0 k or less, the MRI image is good, and there is also a mechanical strength at the time of quenching, so that the consumption of liquid helium can be reduced. Furthermore, especially the circumference
By providing the circumferential heat conduction plates with one plate in direction, the machine
Good mechanical strength and prevent mechanical damage and deformation
Can be.
【００１０】[0010]
【実施例】以下、本発明の一実施例について図面を参照
して詳細に説明する。本実施例によるＭＲＩ装置用超電
導磁石の全体組立構成は、前述した図５の断面図と同様
である。但し、冷凍機には、蓄冷材の材質として、Ｅｒ
3 Ｎｉ合金等の磁性材料を一部または全部用いたものと
し、かつ到達温度が１０k 以下のものとしている。DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. The overall assembling configuration of the superconducting magnet for the MRI apparatus according to the present embodiment is the same as the cross-sectional view of FIG. 5 described above. However, the refrigerator has Er as a material of the cold storage material.
The magnetic material such as 3 Ni alloy and that used part or the whole, and the ultimate temperature is set to the following 10 k.
【００１１】図１は、本実施例のＭＲＩ装置用超電導磁
石における輻射シールドの外筒の構成例を示す斜視図で
ある。図１において、２１は輻射シールド外筒板であ
り、アルミニウム合金板（例えば、Ａ５０８３他）によ
り製作している。これは、図示しない傾斜磁場コイルか
らの印加磁場による渦電流の低減、および超電導コイル
のクエンチ時に発生する電磁力の低減のため、材質を選
定しているものである。FIG. 1 is a perspective view showing a configuration example of an outer cylinder of a radiation shield in a superconducting magnet for an MRI apparatus according to this embodiment. In FIG. 1, reference numeral 21 denotes a radiation shield outer cylinder plate, which is manufactured from an aluminum alloy plate (for example, A5083 or the like). The material is selected in order to reduce eddy current due to a magnetic field applied from a gradient magnetic field coil (not shown) and to reduce electromagnetic force generated when the superconducting coil is quenched.
【００１２】また、２２は純度９９．９９％以上の高純
度アルミニウム材からなる軸熱伝導板であり、輻射シー
ルド外筒板２１に軸方向に、熱伝導が良好な取付け手
法、例えば溶接取付けまたは接着取付け等の手法で、取
付けを行なっている。Reference numeral 22 denotes a shaft heat conducting plate made of a high-purity aluminum material having a purity of 99.99% or more. Mounting is performed by a method such as adhesive mounting.
【００１３】さらに、２３は軸熱伝導板２２と同様に、
純度９９．９９％以上の高純度アルミニウム材からなる
周熱伝導板であり、輻射シールド外筒板２１に円周方向
に、上記と同様に熱伝導が良好な取付け手法、例えば溶
接取付けまたは接着取付け等の手法で、取付けを行なっ
ている。Further, 23 is similar to the shaft heat conducting plate 22,
A circumferential heat conducting plate made of a high-purity aluminum material having a purity of 99.99% or more, which is attached to the radiation shield outer cylinder plate 21 in the circumferential direction in the same manner as described above, with good heat conduction, for example, welding attachment or adhesive attachment. Installation is performed by such methods.
【００１４】さらにまた、６は伝熱板であり、一端は冷
凍機５のヒートステーションに、また他端は軸熱伝導板
２２にそれぞれ結合し、輻射シールドと冷凍機５とを熱
的に結合している。Further, reference numeral 6 denotes a heat transfer plate, one end of which is connected to the heat station of the refrigerator 5 and the other end of which is connected to the shaft heat conduction plate 22, respectively, for thermally connecting the radiation shield and the refrigerator 5 to each other. are doing.
【００１５】次に、以上のように構成した本実施例のＭ
ＲＩ装置用超電導磁石においては、輻射シールドの熱量
は、主に軸熱伝導板２２，周熱伝導板２３を通って伝熱
板６へ流れ、冷凍機５で冷却される。Next, M of the present embodiment constructed as described above is used.
In the superconducting magnet for the RI device, the heat of the radiation shield mainly flows to the heat transfer plate 6 through the shaft heat conduction plate 22 and the peripheral heat conduction plate 23, and is cooled by the refrigerator 5.
【００１６】この場合、高純度アルミニウムとアルミニ
ウム合金の１０k 以下での熱伝導率の比は、約１００倍
以上あるため、輻射シールド内の温度差を低減すること
が可能となり、輻射シールドの温度を下げることができ
る。このため、液体ヘリウムの消費量の低減ができる。
特に、熱量が集中する伝熱板６との結合部または熱集中
部付近の温度差を少なくすることができる。In this case, since the ratio of the thermal conductivity of high-purity aluminum to an aluminum alloy at 10 k or less is about 100 times or more, the temperature difference in the radiation shield can be reduced, and the temperature of the radiation shield can be reduced. Can be lowered. Therefore, the consumption of liquid helium can be reduced.
In particular, it is possible to reduce the temperature difference in the vicinity of the joint with the heat transfer plate 6 where heat is concentrated or in the vicinity of the heat concentrated portion.
【００１７】また、輻射シールド本体には、アルミニウ
ム合金を使用しているため、超電導コイル４のクエンチ
発生の場合にも、輻射シールドに発生する電磁力は比較
的小さな値に抑えることができると共に、機械的強度も
良好であるので、機械的破損、変形を防止することがで
きる。Since the radiation shield body is made of an aluminum alloy, the electromagnetic force generated in the radiation shield can be suppressed to a relatively small value even when the quench of the superconducting coil 4 occurs. Since the mechanical strength is also good, mechanical breakage and deformation can be prevented.
【００１８】さらに、輻射シールド本体にアルミニウム
合金を使用しているため、傾斜磁場コイルの運転時に発
生する渦電流も低減でき、良好なＭＲＩ画像を得ること
ができる。Further, since an aluminum alloy is used for the radiation shield main body, eddy current generated during operation of the gradient magnetic field coil can be reduced, and a good MRI image can be obtained.
【００１９】上述したように、本実施例のＭＲＩ装置用
超電導磁石においては、次のような効果を得ることがで
きる。すなわち、冷凍機５には、蓄冷材の材質としてＥ
ｒ3 Ｎｉ合金等の磁性材料を用い、また純度９９．９９
％以上の高純度アルミニウム材からなる熱伝導板２２，
２３を、冷凍機５との結合部または熱集中部から軸方向
および円周方向に設けているので、輻射シールドの温度
を下げることができ、液体ヘリウム７の消費量を低減す
ることが可能になると共に、十分な機械的強度を有し、
良好なＭＲＩ画像を得ることが可能となる。As described above, the following effects can be obtained in the superconducting magnet for an MRI apparatus according to the present embodiment. That is, the refrigerator 5 has E as a material of the cold storage material.
Using a magnetic material such as r 3 Ni alloy, and having a purity of 99.99
% Or more of the heat conductive plate 22 made of high-purity aluminum material.
23 is provided in the axial direction and the circumferential direction from the connection portion with the refrigerator 5 or the heat concentration portion, so that the temperature of the radiation shield can be reduced, and the consumption of the liquid helium 7 can be reduced. While having sufficient mechanical strength,
A good MRI image can be obtained.
【００２０】より詳しくは、次のような効果を得ること
ができる。 （ａ）蓄冷材の材質としてＥｒ3 Ｎｉ合金等の磁性材料
を用いた冷凍機５と、高純度アルミニウム材からなる軸
熱伝導板２２および周熱伝導板２３とを設けているの
で、輻射シールド温度を１０k 以下の極低温に冷却で
き、液体ヘリウム７の消費量を０．０１ｌ／ｈ以下に低
減することが可能となる。More specifically, the following effects can be obtained. (A) Since the refrigerator 5 using a magnetic material such as an Er 3 Ni alloy as the material of the cold storage material and the axial heat conduction plate 22 and the peripheral heat conduction plate 23 made of a high-purity aluminum material are provided, a radiation shield is provided. The temperature can be cooled to an extremely low temperature of 10 k or less, and the consumption of liquid helium 7 can be reduced to 0.01 l / h or less.
【００２１】（ｂ）輻射シールド本体にアルミニウム合
金を使用しているので、良好な機械的強度を有すると共
に、良好なＭＲＩ画像を得ることが可能となる。 （ｃ）輻射シールド本体にアルミニウム合金を使用して
いるので、超電導コイル４のクエンチ時の電磁力をより
一層低減することが可能となる。(B) Since the radiation shield body is made of an aluminum alloy, it has good mechanical strength and can obtain a good MRI image. (C) Since an aluminum alloy is used for the radiation shield main body, the electromagnetic force at the time of quench of the superconducting coil 4 can be further reduced.
【００２２】尚、本発明は上記実施例に限定されるもの
ではなく、次のようにしても同様に実施できるものであ
る。 （ａ）図２は、本発明のＭＲＩ装置用超電導磁石におけ
る輻射シールドの外筒の他の構成例を示す斜視図であ
り、図１と同一要素には同一符号を付して示している。It should be noted that the present invention is not limited to the above-described embodiment, but can be similarly implemented in the following manner. (A) FIG. 2 is a perspective view showing another configuration example of a radiation shield outer cylinder in a superconducting magnet for an MRI apparatus of the present invention, and the same elements as those in FIG. 1 are denoted by the same reference numerals.
【００２３】図２において、２つの軸熱伝導板２２を上
下方向に（円周方向に）対称位置に取付け、２つの周熱
伝導板２３を軸方向に対称位置に取付けている。かかる
構成とすることにより、２つの軸熱伝導板２２、２つの
周熱伝導板２３を軸方向および円周方向に対称位置に取
付けているため、輻射シールド内の温度差をより一層低
減することが可能になるのは勿論のこと、傾斜磁場コイ
ル運転時の渦電流分布が対称となるため、より一層良好
なＭＲＩ画像を得ることが可能となる。In FIG. 2, two axial heat conductive plates 22 are mounted at vertically symmetric (circumferential) positions, and two peripheral heat conductive plates 23 are mounted at symmetric positions in the axial direction. With this configuration, since the two axial heat conductive plates 22 and the two peripheral heat conductive plates 23 are mounted at symmetric positions in the axial direction and the circumferential direction, the temperature difference in the radiation shield can be further reduced. As a matter of course, since the eddy current distribution during the operation of the gradient magnetic field coil becomes symmetrical, it is possible to obtain an even better MRI image.
【００２４】（ｂ）図３は、本発明のＭＲＩ装置用超電
導磁石における輻射シールドの外筒の他の構成例を示す
斜視図であり、図１と同一要素には同一符号を付して示
している。(B) FIG. 3 is a perspective view showing another configuration example of the outer cylinder of the radiation shield in the superconducting magnet for an MRI apparatus of the present invention, and the same elements as those in FIG. ing.
【００２５】図３において、２４は結合用熱伝導板であ
り、他の軸熱伝導板２２，および周熱伝導板２３より
も、その厚さ、幅寸法等を大きくしている。かかる構成
とすることにより、輻射シールドの熱量の最も集中する
場所の厚さ、幅寸法を大きくしているため、輻射シール
ド内の温度差をより一層低減することができ、より一層
低温の輻射シールド温度を得ることが可能となる。In FIG. 3, reference numeral 24 denotes a heat conducting plate for coupling, which is larger in thickness, width and the like than the other heat conducting plates 22 and 23. By adopting such a configuration, the thickness and the width of the location where the amount of heat of the radiation shield is most concentrated are increased, so that the temperature difference in the radiation shield can be further reduced, and the radiation shield at a lower temperature can be further reduced. It is possible to obtain the temperature.
【００２６】（ｃ）図４は、本発明のＭＲＩ装置用超電
導磁石における円周方向に設ける周熱伝導板の他の構成
例を示す一部拡大図であり、図１と同一要素には同一符
号を付して示している。(C) FIG. 4 is a partially enlarged view showing another example of the configuration of the circumferential heat conducting plate provided in the circumferential direction in the superconducting magnet for an MRI apparatus according to the present invention. The reference numerals are attached.
【００２７】図４において、周熱伝導板２３と輻射シー
ルド外筒板２１との間にスリットを入れ、電気的１ター
ンカット２５を設けている。かかる構成とすることによ
り、周熱伝導板２３に電気的１ターンカットを設けてい
るため、超電導コイル４のクエンチ発生時の電磁力をよ
り一層低減することが可能となる。In FIG. 4, a slit is formed between the peripheral heat conduction plate 23 and the radiation shield outer cylinder plate 21 to provide an electric one-turn cut 25. With such a configuration, since the peripheral heat conductive plate 23 is provided with one electric turn cut, it is possible to further reduce the electromagnetic force of the superconducting coil 4 when quench occurs.
【００２８】[0028]
【発明の効果】以上説明したように本発明のＭＲＩ装置
用超電導磁石によれば、冷凍機により輻射シールドを冷
却してなるＭＲＩ装置用超電導磁石において、上記冷凍
機に、蓄冷材の材質としてＥｒ3 Ｎｉ合金等の磁性材料
を用いると共に、上記輻射シールドとして、純度９９．
９９％以上の高純度アルミニウム材からなる熱伝導板を
設けた輻射シールドを備え、上記熱伝導板として、冷凍
機との結合部または熱集中部から、軸方向および円周方
向に軸熱伝導板および周熱伝導板を設けるようにしたの
で、輻射シールドの温度を下げて液体ヘリウムの消費量
を低減すると共に、良好なＭＲＩ画像を得ることがで
き、装置の小形化かつ安価化を図ることが可能となる。
さらに、特に円周方向に１枚の板で周熱伝導板を設ける
ようにしたので、機械的強度も良好であり、機械的破
損、変形を防止することも可能となる。 As described above, the MRI apparatus of the present invention
According to use superconducting magnets, in the MRI apparatus for a superconducting magnet comprising cooling the radiation shield by the refrigerator, in the refrigerator, with using a magnetic material such as Er 3 Ni alloy as the material of the cold accumulating material, as the radiation shield , Purity 99.
It comprises a radiation shield having a heat conductive plate made of more than 99% of the high purity aluminum material, as the heat conducting plate, frozen
From the connection with the machine or the heat concentration area,
Since as provided Jikunetsu conductive plate and Shunetsu conductive plate in direction, while reducing the consumption of the liquid helium lowers the temperature of the radiation shield, to obtain good MRI image
This makes it possible to reduce the size and cost of the device.
Furthermore, the peripheral heat conduction plate is provided by a single plate, particularly in the circumferential direction.
The mechanical strength is good and the mechanical
Loss and deformation can be prevented.
【図１】本発明によるＭＲＩ装置用超電導磁石における
輻射シールドの外筒の一実施例を示す斜視図。FIG. 1 is a perspective view showing an embodiment of an outer cylinder of a radiation shield in a superconducting magnet for an MRI apparatus according to the present invention.
【図２】本発明によるＭＲＩ装置用超電導磁石における
輻射シールドの外筒の他の実施例を示す斜視図。FIG. 2 is a perspective view showing another embodiment of an outer cylinder of a radiation shield in a superconducting magnet for an MRI apparatus according to the present invention.
【図３】本発明によるＭＲＩ装置用超電導磁石における
輻射シールドの外筒の他の実施例を示す斜視図。FIG. 3 is a perspective view showing another embodiment of an outer cylinder of a radiation shield in a superconducting magnet for an MRI apparatus according to the present invention.
【図４】本発明によるＭＲＩ装置用超電導磁石における
円周方向に設ける周熱伝導板の他の構成例を示す一部拡
大図。FIG. 4 is a partially enlarged view showing another configuration example of the circumferential heat conduction plate provided in the circumferential direction in the superconducting magnet for the MRI apparatus according to the present invention.
【図５】ＭＲＩ装置用超電導磁石の全体組立構成例を示
す断面図。FIG. 5 is a sectional view showing an example of the overall assembly configuration of a superconducting magnet for an MRI apparatus.
１…真空容器、２ａ…第１の輻射シールド、２ｂ…第２
の輻射シールド、３…ヘリウム容器、４…超電導コイ
ル、５…冷凍機、６…伝熱板、６ａ…第１の伝熱板、６
ｂ…第２の伝熱板、７…液体ヘリウム、２１…輻射シー
ルド外筒板、２２…軸熱伝導板、２３…周熱伝導板、２
４…結合用熱伝導板、２５…電気的１ターンカット。DESCRIPTION OF SYMBOLS 1 ... Vacuum container, 2a ... 1st radiation shield, 2b ... 2nd
3, a helium container, 4, a superconducting coil, 5, a refrigerator, 6, a heat transfer plate, 6a, a first heat transfer plate, 6
b: second heat transfer plate, 7: liquid helium, 21: radiation shield outer tube plate, 22: axial heat conductive plate, 23: peripheral heat conductive plate, 2
4 ... Heat conduction plate for coupling, 25 ... Electrical one-turn cut.
───────────────────────────────────────────────────── フロントページの続き (58)調査した分野(Int.Cl.7，ＤＢ名) H01F 6/00 - 6/06 ──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. 7 , DB name) H01F 6/00-6/06
Claims (2)
るＭＲＩ装置用超電導磁石において、 前記冷凍機に、蓄冷材の材質としてＥｒ3 Ｎｉ合金等の
磁性材料を用いると共に、 前記輻射シールドとして、純度９９．９９％以上の高純
度アルミニウム材からなる熱伝導板を設けた輻射シール
ドを備え、 前記熱伝導板として、前記冷凍機との結合部または熱集
中部から、軸方向および円周方向に軸熱伝導板および周
熱伝導板を設けるようにしたことを特徴とするＭＲＩ装
置用超電導磁石。1. A superconducting magnet for an MRI apparatus in which a radiation shield is cooled by a refrigerator, wherein a magnetic material such as an Er 3 Ni alloy is used as a material of a cold storage material for the refrigerator, and a purity is used as the radiation shield. A radiation shield provided with a heat conductive plate made of a high-purity aluminum material of 99.99% or more, wherein the heat conductive plate is axially and circumferentially connected from a joint with the refrigerator or a heat concentrated portion; A superconducting magnet for an MRI apparatus, wherein a heat conducting plate and a peripheral heat conducting plate are provided.
取付けると共に、前記周熱伝導板を軸方向に対称位置に
取付けるようにしたことを特徴とする請求項１に記載の
ＭＲＩ装置用超電導磁石。2. The MRI apparatus according to claim 1, wherein the axial heat conductive plate is mounted at a position symmetrical in the circumferential direction, and the peripheral heat conductive plate is mounted at a position symmetrical in the axial direction. For superconducting magnets.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18485893A JP3260497B2 (en) | 1993-07-27 | 1993-07-27 | Superconducting magnet for MRI equipment |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP18485893A JP3260497B2 (en) | 1993-07-27 | 1993-07-27 | Superconducting magnet for MRI equipment |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH0745423A JPH0745423A (en) | 1995-02-14 |
| JP3260497B2 true JP3260497B2 (en) | 2002-02-25 |
Family
ID=16160543
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP18485893A Expired - Lifetime JP3260497B2 (en) | 1993-07-27 | 1993-07-27 | Superconducting magnet for MRI equipment |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JP3260497B2 (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPWO2013150951A1 (en) * | 2012-04-06 | 2015-12-17 | 株式会社日立メディコ | Superconducting magnet and magnetic resonance imaging system |
| CN102930946B (en) * | 2012-09-27 | 2014-12-24 | 湖北省电力公司电力科学研究院 | Conduction cooling device for high-temperature superconducting magnet |
| JP2022133593A (en) * | 2021-03-02 | 2022-09-14 | 株式会社東芝 | Superconducting electromagnet device and cooling method for superconducting electromagnet device |
-
1993
- 1993-07-27 JP JP18485893A patent/JP3260497B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH0745423A (en) | 1995-02-14 |
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