JPH0510335Y2 - - Google Patents
Info
- Publication number
- JPH0510335Y2 JPH0510335Y2 JP8375087U JP8375087U JPH0510335Y2 JP H0510335 Y2 JPH0510335 Y2 JP H0510335Y2 JP 8375087 U JP8375087 U JP 8375087U JP 8375087 U JP8375087 U JP 8375087U JP H0510335 Y2 JPH0510335 Y2 JP H0510335Y2
- Authority
- JP
- Japan
- Prior art keywords
- coil
- superconducting
- magnetic field
- magnet device
- magnetic
- 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
Links
- 230000005291 magnetic effect Effects 0.000 claims description 34
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 12
- 239000007788 liquid Substances 0.000 claims description 8
- 230000004323 axial length Effects 0.000 claims description 6
- 229910052757 nitrogen Inorganic materials 0.000 claims description 6
- 230000005855 radiation Effects 0.000 claims description 5
- 239000003507 refrigerant Substances 0.000 claims description 4
- 239000002887 superconductor Substances 0.000 claims description 2
- 238000010586 diagram Methods 0.000 description 4
- 230000000694 effects Effects 0.000 description 4
- 238000004804 winding Methods 0.000 description 4
- 229910052788 barium Inorganic materials 0.000 description 3
- 239000002826 coolant Substances 0.000 description 3
- 238000013421 nuclear magnetic resonance imaging Methods 0.000 description 3
- 229910052727 yttrium Inorganic materials 0.000 description 3
- DSAJWYNOEDNPEQ-UHFFFAOYSA-N barium atom Chemical compound [Ba] DSAJWYNOEDNPEQ-UHFFFAOYSA-N 0.000 description 2
- 238000001816 cooling Methods 0.000 description 2
- 239000010949 copper Substances 0.000 description 2
- 230000005292 diamagnetic effect Effects 0.000 description 2
- 239000001307 helium Substances 0.000 description 2
- 229910052734 helium Inorganic materials 0.000 description 2
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 description 2
- 229910052746 lanthanum Inorganic materials 0.000 description 2
- FZLIPJUXYLNCLC-UHFFFAOYSA-N lanthanum atom Chemical compound [La] FZLIPJUXYLNCLC-UHFFFAOYSA-N 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- VWQVUPCCIRVNHF-UHFFFAOYSA-N yttrium atom Chemical compound [Y] VWQVUPCCIRVNHF-UHFFFAOYSA-N 0.000 description 2
- RYGMFSIKBFXOCR-UHFFFAOYSA-N Copper Chemical compound [Cu] RYGMFSIKBFXOCR-UHFFFAOYSA-N 0.000 description 1
- QPLDLSVMHZLSFG-UHFFFAOYSA-N Copper oxide Chemical class [Cu]=O QPLDLSVMHZLSFG-UHFFFAOYSA-N 0.000 description 1
- 230000002411 adverse Effects 0.000 description 1
- 229910052802 copper Inorganic materials 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Landscapes
- Magnetic Resonance Imaging Apparatus (AREA)
Description
【考案の詳細な説明】
〔産業上の利用分野〕
この考案は、核磁気共鳴撮像等に用いられる磁
石装置に関するものである。[Detailed Description of the Invention] [Industrial Application Field] This invention relates to a magnet device used for nuclear magnetic resonance imaging and the like.
第3図及び第4図は各々例えば特開昭60−
123756号公報に示された従来の核磁気共鳴撮像用
の磁石装置を示す断面図及び磁力線の様子を示す
模式図である。図において1は超電導磁石装置、
2は熱ふく射シールド用の液体窒素、3は超電導
コイル冷却用の液体ヘリウム、4は磁気シールド
用の第2超電導コイル(以下第2コイルと記す)、
5は第2コイルの巻枠、6は主磁界発生用の第1
超電導コイル(以下第1コイルと記す)、7は第
1コイルの巻枠、8は磁場空間、9は第2コイル
の作る磁力線、10は第1コイルの作る磁力線で
ある。
Figures 3 and 4 are, for example, Japanese Unexamined Patent Application Publication No. 1989-1999-
123756 is a cross-sectional view showing a conventional magnet device for nuclear magnetic resonance imaging, and a schematic diagram showing lines of magnetic force. FIG. In the figure, 1 is a superconducting magnet device,
2 is liquid nitrogen for heat radiation shielding, 3 is liquid helium for cooling superconducting coils, 4 is a second superconducting coil (hereinafter referred to as the second coil) for magnetic shielding,
5 is the winding frame of the second coil, 6 is the first coil for generating the main magnetic field.
A superconducting coil (hereinafter referred to as a first coil), 7 is a winding frame of the first coil, 8 is a magnetic field space, 9 is a line of magnetic force created by the second coil, and 10 is a line of magnetic force created by the first coil.
次に動作について説明する。 Next, the operation will be explained.
核磁気共鳴撮像用の磁石装置は、磁場空間8に
0.5〜2.0テスラの非常に強い磁界が必要である。
この磁界は主に巻枠7に設けた第1コイル6によ
り発生する。しかし、この第1コイル6によつて
発生する磁力線は、磁場空間8のみならず、第4
図のように外周辺に分布する。つまり外部への漏
れ磁界となり、周辺の磁性体や計測器等に悪影響
をおよぼす。これを避けるため、第1コイルの半
径方向の外側の巻枠5に第2コイル4を置き、第
1コイル6と逆の方向に電流を通す。つまり、第
1コイル6が超電導磁石装置1の周辺部で発生す
る磁界の強さと同程度で、方向が逆の磁界を第2
コイル4で発生させる。この結果、周辺部では2
つのコイルにより発生する磁界がお互いに打ち消
し合い、周辺の磁性体や計測器等への影響を減少
させる。 The magnet device for nuclear magnetic resonance imaging is placed in the magnetic field space 8.
A very strong magnetic field of 0.5-2.0 Tesla is required.
This magnetic field is mainly generated by the first coil 6 provided on the winding frame 7. However, the lines of magnetic force generated by the first coil 6 are not limited to the magnetic field space 8, but also to the fourth coil.
It is distributed around the outside as shown in the figure. In other words, it becomes a leakage magnetic field to the outside, which adversely affects surrounding magnetic materials, measuring instruments, etc. In order to avoid this, the second coil 4 is placed on the winding frame 5 radially outside the first coil, and current is passed in the opposite direction to the first coil 6. In other words, the first coil 6 generates a magnetic field with the same strength and opposite direction as the magnetic field generated around the superconducting magnet device 1 into the second coil.
It is generated by coil 4. As a result, 2
The magnetic fields generated by the two coils cancel each other out, reducing the impact on surrounding magnetic materials and measuring instruments.
従来の磁石装置は以上のように構成されている
ので、磁場空間8の磁界も減少する。このため必
要な磁界強度を得るには、第1コイル6で発生す
る磁界強度を上げることが必要で、また、高価な
超電導線を使用した第2コイル4を設置するなど
の問題点があつた。
Since the conventional magnet device is configured as described above, the magnetic field in the magnetic field space 8 is also reduced. Therefore, in order to obtain the necessary magnetic field strength, it was necessary to increase the magnetic field strength generated by the first coil 6, and there were also problems such as installing the second coil 4 using expensive superconducting wire. .
この考案は、上記のような問題点を解消するた
めになされたもので、高価な第2コイルが不用で
第1コイルの発生磁界強度を上げる必要がない安
価な磁石装置を得ることを目的とする。 This idea was made to solve the above problems, and the purpose was to obtain an inexpensive magnet device that does not require an expensive second coil and does not require increasing the magnetic field strength generated by the first coil. do.
この考案に係る磁石装置は超電導コイルの周囲
に設けられた熱ふく射シールド内に、軸方向の長
さが超電導コイルより長く、シールド内に封入さ
れた冷媒で超電導状態に冷却された円筒を配設し
たものである。
The magnet device according to this invention has a cylinder whose axial length is longer than the superconducting coil and is cooled to a superconducting state with a refrigerant sealed in the shield in a heat radiation shield provided around the superconducting coil. This is what I did.
この考案における超電導状態に冷却された円筒
は、超電導現象の性質の一つである反磁性効果に
より磁力線を内側に閉じ込めるため、周辺部への
漏れ磁界が少なくなる。また磁力線の外部への漏
れを小さくするにはコイルの外側に配設する程よ
く、またコイルより長い方がよいが、この考案の
ものではシールド内に配設されており、従来より
外側でありコイルより軸方向の長さが長いので効
果が上がる。
The cylinder cooled to a superconducting state in this invention confines the lines of magnetic force inside due to the diamagnetic effect, which is one of the properties of the superconducting phenomenon, thereby reducing leakage of magnetic fields to the surrounding area. In addition, in order to reduce the leakage of magnetic lines of force to the outside, it is better to place it outside the coil, and it is better to have it longer than the coil, but in this invention, it is placed inside the shield, and it is outside the coil compared to the conventional one. The longer length in the axial direction increases the effectiveness.
以下、この考案の一実施例を図について説明す
る。第1図及び第2図は各々この考案の一実施例
による磁石装置を示す断面図及び磁力線の様子を
示す模式図である。
An embodiment of this invention will be described below with reference to the drawings. FIGS. 1 and 2 are a cross-sectional view showing a magnet device according to an embodiment of the invention and a schematic view showing lines of magnetic force, respectively.
図において、11は熱ふく射シールド内に配設
され、軸方向の長さが超電導コイルより長い円筒
であり、シールド内の液体チツ素2により超電導
状態に冷却されている。 In the figure, numeral 11 is a cylinder that is disposed within a heat radiation shield, has a longer axial length than the superconducting coil, and is cooled to a superconducting state by liquid nitrogen 2 within the shield.
次に動作について説明する。 Next, the operation will be explained.
磁場空間8に必要な磁界を超電導コイル6で発
生させることは従来装置と同様である。 Generating the necessary magnetic field in the magnetic field space 8 with the superconducting coil 6 is similar to the conventional device.
一方、この実施例においては、円筒11はラン
タン、バリウム、イトリウム、銅の酸化物、例え
ば(Y,Ba)3Cu2O7よりなり、従来より超電導コ
イル6の半径方向外側のシールド内に設置され、
軸方向の長さも超電導コイル6より長く設けられ
ている。 On the other hand, in this embodiment, the cylinder 11 is made of oxides of lanthanum, barium, yttrium, and copper, such as (Y, Ba) 3 Cu 2 O 7 , and is conventionally installed in the shield outside the superconducting coil 6 in the radial direction. is,
The length in the axial direction is also longer than the superconducting coil 6.
上記ランタン、バリウム、イトリウム、銅の酸
化物などで構成された超電導物性材は高温超電導
体と称され、80°K程度の温度で超電導状態に転
移することが実験で確認されており、例えばシー
ルド内の液体チツ素で冷却することにより超電導
状態になることができ、その結果、反磁性の効果
によつて超電導コイル6の発生する磁力線の分布
は第2図の磁力線10のように、外周部へ出る量
が少なくなる。 The superconducting physical materials made of lanthanum, barium, yttrium, copper oxides, etc. mentioned above are called high-temperature superconductors, and it has been experimentally confirmed that they transition to a superconducting state at a temperature of about 80°K. The superconducting state can be achieved by cooling with liquid nitrogen inside the coil, and as a result, the distribution of the magnetic lines of force generated by the superconducting coil 6 due to the diamagnetic effect is as shown in the magnetic lines of force 10 in FIG. The amount that comes out will decrease.
また、前述のように円筒11は軸方向の長さが
超電導コイル6より長く、また従来よりコイル6
から離れて設置できるので周辺部への漏れ磁界を
より弱くすることができる。 In addition, as mentioned above, the cylinder 11 has a longer axial length than the superconducting coil 6, and the cylinder 11 has a longer axial length than the superconducting coil 6.
Since it can be installed away from the surrounding area, the leakage magnetic field to the surrounding area can be further weakened.
また、このような円筒11は構成が簡単なので
安価にできる効果もある。 Furthermore, since the cylinder 11 has a simple structure, it has the advantage of being inexpensive.
なお、上記実施例では、超電導コイル6の冷却
媒体として液体ヘリウム、円筒11の冷却媒体と
して液体チツ素を例に説明したが、これらに限ら
ず超電導コイル6および円筒11がそれぞれ超電
導状態に転移するものであれば、どのような冷却
媒体を使用しても同様の効果を奏する。 In the above embodiment, liquid helium is used as the cooling medium for the superconducting coil 6, and liquid nitrogen is used as the cooling medium for the cylinder 11. The same effect can be achieved no matter what kind of cooling medium is used.
以上のようにこの考案によれば超電導コイルの
周囲に設けられた熱ふく射シールド内に軸方向の
長さが超電導コイルより長く、シールド内に封入
された冷媒で超電導状態に冷却された円筒を配設
したので、周辺部への漏れ磁界の少ない磁石装置
が安価に得られる効果がある。
As described above, according to this invention, a cylinder whose axial length is longer than the superconducting coil and is cooled to a superconducting state by the refrigerant sealed in the shield is disposed within the thermal radiation shield provided around the superconducting coil. This has the effect that a magnet device with less magnetic field leakage to the surrounding area can be obtained at low cost.
第1図及び第2図は各々この考案の一実施例に
よる磁石装置を示す断面図及び磁力線の様子を示
す模式図、並びに第3図及び第4図は各々従来の
磁石装置を示す断面図及び磁力線の様子を示す模
式図である。
図において、1……超電導磁石装置、2……液
体チツ素、6……超電導コイル、8……磁場空
間、11……円筒である。なお、図中、同一符号
は同一又は相当部分を示す。
FIGS. 1 and 2 are a cross-sectional view and a schematic diagram showing the lines of magnetic force, respectively, showing a magnet device according to an embodiment of the invention, and FIGS. 3 and 4 are a cross-sectional view and a schematic diagram showing a conventional magnet device, respectively. FIG. 2 is a schematic diagram showing the state of magnetic lines of force. In the figure, 1... superconducting magnet device, 2... liquid nitrogen, 6... superconducting coil, 8... magnetic field space, 11... cylinder. In addition, in the figures, the same reference numerals indicate the same or corresponding parts.
Claims (1)
超電導コイルの周囲に設けられた熱ふく射シー
ルド、このシールド内に配設され、上記シール
ド内に封入された冷媒で超電導状態に冷却さ
れ、軸方向の長さが上記超電導コイルより長い
円筒を備えた磁石装置。 (2) 冷媒は液体チツ素である実用新案登録請求の
範囲第1項記載の磁石装置。 (3) 円筒は高温超電導体である実用新案登録請求
の範囲第1項又は第2項記載の磁石装置。[Claims for Utility Model Registration] (1) A superconducting coil having a magnetic field space inside, a heat radiation shield provided around the superconducting coil, and a refrigerant disposed within the shield and sealed within the shield. A magnet device comprising a cylinder cooled to a superconducting state and having a longer axial length than the superconducting coil. (2) The magnet device according to claim 1, wherein the refrigerant is liquid nitrogen. (3) The magnet device according to claim 1 or 2, wherein the cylinder is a high-temperature superconductor.
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8375087U JPH0510335Y2 (en) | 1987-05-29 | 1987-05-29 |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
JP8375087U JPH0510335Y2 (en) | 1987-05-29 | 1987-05-29 |
Publications (2)
Publication Number | Publication Date |
---|---|
JPS63191608U JPS63191608U (en) | 1988-12-09 |
JPH0510335Y2 true JPH0510335Y2 (en) | 1993-03-15 |
Family
ID=30937621
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
JP8375087U Expired - Lifetime JPH0510335Y2 (en) | 1987-05-29 | 1987-05-29 |
Country Status (1)
Country | Link |
---|---|
JP (1) | JPH0510335Y2 (en) |
-
1987
- 1987-05-29 JP JP8375087U patent/JPH0510335Y2/ja not_active Expired - Lifetime
Also Published As
Publication number | Publication date |
---|---|
JPS63191608U (en) | 1988-12-09 |
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