JPH01254154A - Magnetic field correcting device - Google Patents
Magnetic field correcting deviceInfo
- Publication number
- JPH01254154A JPH01254154A JP63078123A JP7812388A JPH01254154A JP H01254154 A JPH01254154 A JP H01254154A JP 63078123 A JP63078123 A JP 63078123A JP 7812388 A JP7812388 A JP 7812388A JP H01254154 A JPH01254154 A JP H01254154A
- Authority
- JP
- Japan
- Prior art keywords
- cylinder
- magnetic field
- rail
- rails
- iron piece
- 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
Links
- 239000000853 adhesive Substances 0.000 abstract description 4
- 230000001070 adhesive effect Effects 0.000 abstract description 4
- 239000000126 substance Substances 0.000 abstract description 3
- 238000003466 welding Methods 0.000 abstract description 2
- 229910000831 Steel Inorganic materials 0.000 abstract 1
- 239000010959 steel Substances 0.000 abstract 1
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 71
- 229910052742 iron Inorganic materials 0.000 description 36
- 230000000694 effects Effects 0.000 description 7
- 238000002595 magnetic resonance imaging Methods 0.000 description 7
- 238000010586 diagram Methods 0.000 description 2
- 239000000696 magnetic material Substances 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 239000002390 adhesive tape Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000005553 drilling Methods 0.000 description 1
- 150000002505 iron Chemical class 0.000 description 1
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01R—MEASURING ELECTRIC VARIABLES; MEASURING MAGNETIC VARIABLES
- G01R33/00—Arrangements or instruments for measuring magnetic variables
- G01R33/20—Arrangements or instruments for measuring magnetic variables involving magnetic resonance
- G01R33/28—Details of apparatus provided for in groups G01R33/44 - G01R33/64
- G01R33/38—Systems for generation, homogenisation or stabilisation of the main or gradient magnetic field
- G01R33/387—Compensation of inhomogeneities
- G01R33/3873—Compensation of inhomogeneities using ferromagnetic bodies ; Passive shimming
Landscapes
- Physics & Mathematics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- General Physics & Mathematics (AREA)
- Magnetic Resonance Imaging Apparatus (AREA)
Abstract
Description
【発明の詳細な説明】
〔発明の目的〕
（産業上の利用分野）
本発明は、磁気共鳴イメージング装置（ＭＲＩ装置）の
磁界補正装置に関する。DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a magnetic field correction device for a magnetic resonance imaging apparatus (MRI apparatus).
（従来の技術）
ＭＨＩ装置は、高磁界を用いるほど、画像が良くなるた
め、超電導マグネットが普及されている。(Prior Art) Superconducting magnets are widely used in MHI devices because the higher the magnetic field used, the better the image quality.
また、マグネット内の診断空間においては、高均一磁界
が要求されるので、高精度な設計がなされるが、実際に
は、マグネットの製造過程における製作寸法誤差や、マ
グネットを設置した場所の周辺にある磁性体の影響など
により、実際の診断空間内の磁界均一度は、悪くなって
しまう、そこで、磁界補正装置が用いられ、その補正装
置の１つに、鉄シムと呼ばれる小さな鉄片がある。この
鉄片１を第１１図のように超電導マグネット２の常温ボ
ア３内に張り付けて、診断空間４の磁界を補正する。In addition, the diagnostic space inside the magnet requires a highly uniform magnetic field, so it is designed with high precision. Due to the influence of certain magnetic substances, the uniformity of the magnetic field in the actual diagnostic space deteriorates, so a magnetic field correction device is used, and one of the correction devices is a small piece of iron called an iron shim. This iron piece 1 is stuck inside the normal temperature bore 3 of the superconducting magnet 2 as shown in FIG. 11 to correct the magnetic field in the diagnostic space 4.
補正にあたっては、所定の磁界均一度になるまで。During correction, until the specified magnetic field uniformity is achieved.
複数個の鉄片１をボア３内の適切な場所に張り付ける。A plurality of iron pieces 1 are pasted at appropriate locations within the bore 3.
（発明が解決しようとする課題）
前述したようにＭＨＩ装置では、超電導マグネットを用
いて高磁界にした方が画像が良くなるが、高磁界にする
と、鉄片に働く電磁力が増大し、張り付けが困難になっ
たり、張り付けた鉄片がはずれてしまったりして、磁界
の補正がしにくくなるという問題がある。また、強力な
接着剤で固定してしまうと、補正過程で、はずしたい場
合に、こまってしまうという問題がある。(Problems to be Solved by the Invention) As mentioned above, in an MHI device, using a superconducting magnet to create a high magnetic field provides a better image, but when using a high magnetic field, the electromagnetic force acting on the iron piece increases, making it difficult to attach the iron piece. There is a problem that it becomes difficult to correct the magnetic field because it becomes difficult or the attached iron piece comes off. Furthermore, if it is fixed with a strong adhesive, there is a problem that it will be difficult to remove it during the correction process.
そこで本発明は、鉄片がはずれないような、また、補正
しやすい構成の磁界補正装置を提供することを目的とす
る。SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a magnetic field correction device that prevents the iron piece from coming off and has a structure that allows easy correction.
（発明の構成〕
（課題を解決するための手段）
本発明においては、第１図に示すように、マグネット本
体の内側に設けた非磁性体の複数のリングレール７の内
面に、その中心軸と平行に複数の非磁性体の直線レール
６を取りつけ、このレールに磁性体片をとりつける。あ
るいは円筒体５に磁性体片をとりつける。(Structure of the Invention) (Means for Solving the Problems) In the present invention, as shown in FIG. A plurality of linear rails 6 made of non-magnetic material are attached in parallel with the cylindrical body 5, and magnetic pieces are attached to the rails.Alternatively, magnetic pieces are attached to the cylindrical body 5.
（作 用）
このような構造であると、レールあるいは円筒体にそっ
て磁性体片を移動し装置調整をすることができるので、
磁界補正を精密にかつ容易におこなうことができる。(Function) With this structure, it is possible to adjust the device by moving the magnetic piece along the rail or cylindrical body.
Magnetic field correction can be performed precisely and easily.
（実施例）
本発明の実施例を第１図に示す。非磁性体の円筒５の内
面に、円筒５の中心軸と平行に、断面が第２図のような
形の非磁性体の直線レール、及び円筒５と同軸のリング
レール７を、それぞれ複数個取りつける。ここで、レー
ルと円筒とは溶接等で固定する。このようなレールのつ
いた円筒５を第６図のようにＭＲＩ用超用溝電導マグネ
ット２温ボア３に取りつけた構成とする。(Example) An example of the present invention is shown in FIG. On the inner surface of the non-magnetic cylinder 5, parallel to the central axis of the cylinder 5, a plurality of non-magnetic straight rails having a cross section as shown in FIG. 2 and a ring rail 7 coaxial with the cylinder 5 are provided. Attach. Here, the rail and cylinder are fixed by welding or the like. The cylinder 5 with such a rail is attached to the two-warm bore 3 of a super conductive groove magnet for MRI as shown in FIG.
直線レール６及びリングレール７の断面は、第２図に示
すように、カーテンレールのような形のものとする。こ
のような形のレールに、第３図のように、断面が長方形
の鉄片１または、断面が凸形の鉄片１′をはめこみ、所
定の位置まですべらせて、テープあるいは接着剤等で固
定する。また。The cross sections of the straight rail 6 and the ring rail 7 are shaped like a curtain rail, as shown in FIG. As shown in Figure 3, fit the iron piece 1 with a rectangular cross section or the iron piece 1' with a convex cross section into the rail of this type, slide it to a specified position, and fix it with tape or adhesive. . Also.
リングレール７の場合は、第４図のように、リングの１
カ所に切欠９を設け、ここから、直方体鉄片１又は凸型
鉄片１′をはめこみ、所定の位置までもっていき、固定
する。また、リングレール７の外周には、突起１０をつ
けることにより、第５図にように、リングレール７を円
筒５の内面につけら 、れた直線レール６にはめこむこ
とができる。こうすることにより、リングレール７を軸
方向にすべらせて、リングレール７を任意の位置に置く
ことができる。In the case of ring rail 7, as shown in Figure 4, one of the rings
Notches 9 are provided at several locations, from which the rectangular parallelepiped iron piece 1 or the convex iron piece 1' is fitted, brought to a predetermined position, and fixed. Further, by attaching a protrusion 10 to the outer periphery of the ring rail 7, the ring rail 7 can be fitted into the linear rail 6 attached to the inner surface of the cylinder 5, as shown in FIG. By doing so, it is possible to slide the ring rail 7 in the axial direction and place the ring rail 7 at an arbitrary position.
このように、数本の直線レールと、数個のリングレール
を取りつけた円筒５をＭＲＩ用超用溝電導マグネット２
温ボア３内に第６図のように取りつける。In this way, the cylinder 5 to which several straight rails and several ring rails are attached is connected to the groove conductive magnet 2 for MRI.
Install it inside the warm bore 3 as shown in Figure 6.
このような構成とすることにより、鉄片がレール内には
めこめられているので、電磁力が働いていても、鉄片が
はずれなくなり、磁界補正が容易にできる。With this configuration, since the iron piece is fitted into the rail, the iron piece will not come off even if an electromagnetic force is applied, and the magnetic field can be easily corrected.
鉄片の形は、第３図に示すような直方体の鉄片１または
、凸型の鉄片１′とする。また、リングレール７の外周
には、第４図のように突起１０を取りつけ、これを第５
図のように円筒内面に取りつけた直線レール６にはめこ
む。このような構成とすれば、リングレール７は軸方向
に移動することができる。The shape of the iron piece is a rectangular parallelepiped iron piece 1 as shown in FIG. 3 or a convex iron piece 1'. Further, a protrusion 10 is attached to the outer periphery of the ring rail 7 as shown in FIG.
Fit it into the straight rail 6 attached to the inner surface of the cylinder as shown in the figure. With such a configuration, the ring rail 7 can move in the axial direction.
直線レール６に鉄片１はたは１′をはめこむには、直線
レール６の両端からすべらせてはめこむ。また、リング
レール７に鉄片１または１′をはめこむには、リングレ
ール７に設けた切欠９（第４図）から、鉄片１または１
′を入れ、円周方向にすべらせればよい。鉄片をレール
に固定するには、接着テープ等を用いる。To fit the iron piece 1 or 1' onto the straight rail 6, it is fitted by sliding it from both ends of the straight rail 6. In order to fit the iron piece 1 or 1' into the ring rail 7, insert the iron piece 1 or 1' into the ring rail 7 from the notch 9 (Fig. 4).
’ and slide it in the circumferential direction. Use adhesive tape or the like to secure the iron pieces to the rails.
このようにして、数個、あるいは数十個の鉄シムを用い
て、所定の磁界均一度になるまで、磁界補正をして、鉄
片の位置が決まったら、接着剤等で固定する。In this way, the magnetic field is corrected using several or dozens of iron shims until a predetermined magnetic field uniformity is achieved, and once the position of the iron piece is determined, it is fixed with adhesive or the like.
このような構成とすることにより、高磁界になり、電磁
力が増大しても鉄片がはずれなくなる効果があり、また
、鉄片をレール内で移動させることができるので、容“
易に鉄片による磁界補正ができる効果がある。This configuration has the effect of preventing the iron piece from coming off even if the magnetic field is high and the electromagnetic force increases.Also, since the iron piece can be moved within the rail, the capacity is reduced.
This has the effect of easily correcting the magnetic field using the iron piece.
（他の実施例１）
鉄片の固定方法の他の実施例を第７図、第９図に示す、
これは、非磁性体の円筒５に数個のボルト穴１１をあけ
たもので、ここに、第８図に示すようなボルトを通す穴
１１′をあけた直方体の鉄片１゛をボルト１２で固定す
るものである。(Other Embodiment 1) Another embodiment of the iron piece fixing method is shown in FIGS. 7 and 9.
This is a cylinder 5 made of non-magnetic material with several bolt holes 11 drilled therein, and a rectangular parallelepiped iron piece 1'' with holes 11' for passing bolts as shown in FIG. It is fixed.
このように、ボルト穴１１を円筒５に多数あけることに
より、鉄片１′をボルト１２で固定できるので、鉄片１
′が電磁力ではずれない効果があり、磁界補正が容易に
できる効果がある。In this way, by drilling a large number of bolt holes 11 in the cylinder 5, the iron piece 1' can be fixed with the bolts 12.
' has the effect of not being removed by electromagnetic force, and has the effect of making it easy to correct the magnetic field.
（他の実施例２）
第１０図では、直線レール６を、ＭＲＩ用超電感マグネ
ット２の常温ボア３に、直接取りつけたものを示す。(Other Embodiment 2) FIG. 10 shows a linear rail 6 directly attached to the normal temperature bore 3 of the superelectric magnet 2 for MRI.
このような構成としても、第１図に示す円筒を用いた時
と同様な効果がある。Even with such a configuration, the same effect as when using the cylinder shown in FIG. 1 can be obtained.
以上述べたように、本発明の磁界補正装置においては高
磁界により電磁力が増大しても鉄シムがはずれない効果
があるとともに、鉄シムを任意の位置に固定できるので
、磁界補正が容易に行なえる効果がある６As described above, the magnetic field correction device of the present invention has the effect that the iron shims do not come off even if the electromagnetic force increases due to a high magnetic field, and the iron shims can be fixed at any position, making it easy to correct the magnetic field. 6.
第１図は本発明の磁界補正装置の実施例を示す斜視図、
第２図は上記実施例に用いるレールの断面図、第３図は
上記実施例に用いる直線レールと、それにはめこむ鉄片
を示す図、第４図は同装置に用いるリングレールを示す
図、第５図は直線レールにリングレールをはめこんだ所
を示す図、第６図は本発明の磁界補正装置をＭＲＩ用マ
グネットにはめこむ所の図、第７図は本発明の磁界補正
装置の他の実施例を示す図、第８図は第７図に示す装置
に用いる鉄片の断面を示す図、第９図は第８図に示す鉄
片を第７図に示す装置に取りつけた所を示す図、第１０
図は第１図の変形例で直接レールを超電導マグネットに
取りつけた所を示す図、第１１図は超電導マグネットの
常温ボア内に鉄シムをはりつけた従来の装置を示す図で
ある。
１．１’、１’・・・鉄シム ２・・・ＭＲＩ用超電
導マグネット５・・・円筒 ６・・・直線
レール７・・・リングレール １０・・・突起１１
・・・ボルト穴
代理人 弁理士 則 近 憲 佑
同 第子丸 健
第２図
第３図
Ｏ
第４図
第５ｖ！Ｊ
第６図
第７図
第８図
第９図FIG. 1 is a perspective view showing an embodiment of the magnetic field correction device of the present invention;
Figure 2 is a sectional view of the rail used in the above embodiment, Figure 3 is a diagram showing the straight rail used in the above embodiment and the iron piece fitted into it, Figure 4 is a diagram showing the ring rail used in the same device, Figure 5 shows the ring rail fitted into the straight rail, Figure 6 shows the magnetic field correction device of the present invention fitted into an MRI magnet, and Figure 7 shows the magnetic field correction device of the present invention and other parts. FIG. 8 is a cross-sectional view of the iron piece used in the device shown in FIG. 7, and FIG. 9 is a view showing the iron piece shown in FIG. 8 attached to the device shown in FIG. 7. , 10th
This figure shows a modified example of FIG. 1 in which a rail is directly attached to a superconducting magnet, and FIG. 11 shows a conventional device in which an iron shim is attached to the normal temperature bore of a superconducting magnet. 1.1', 1'... Iron shim 2... Superconducting magnet for MRI 5... Cylinder 6... Straight rail 7... Ring rail 10... Protrusion 11
...Bolt Hole Agent Patent Attorney Nori Ken Chika Yudo Ken Daishimaru Figure 2 Figure 3 O Figure 4 Figure 5 V! J Figure 6 Figure 7 Figure 8 Figure 9
Claims (1)
いはリングレールと直線レールによって形成したかご状
の支持体に磁性体片をとりつけたことを特徴とする磁界
補正装置。A magnetic field correction device characterized in that a magnetic piece is attached to a cylindrical or cage-shaped support formed by a ring rail and a straight rail provided inside a cylindrical magnet body.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63078123A JPH01254154A (en) | 1988-04-01 | 1988-04-01 | Magnetic field correcting device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63078123A JPH01254154A (en) | 1988-04-01 | 1988-04-01 | Magnetic field correcting device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPH01254154A true JPH01254154A (en) | 1989-10-11 |
Family
ID=13653107
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63078123A Pending JPH01254154A (en) | 1988-04-01 | 1988-04-01 | Magnetic field correcting device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH01254154A (en) |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07250819A (en) * | 1991-12-19 | 1995-10-03 | General Electric Co <Ge> | Side approach picture forming magnet wherein shim is passively applied |
| JP2007526058A (en) * | 2004-03-05 | 2007-09-13 | シーメンス アクチエンゲゼルシヤフト | Magnetic field adjustment device |
| US7683624B2 (en) | 2007-05-25 | 2010-03-23 | Mitsubishi Electric Corporation | Magnetic field adjustment device and magnetic field adjustment method for superconducting magnet |
| WO2011122403A1 (en) * | 2010-03-30 | 2011-10-06 | ジャパンスーパーコンダクタテクノロジー株式会社 | Superconducting magnet device |
| JP2011255027A (en) * | 2010-06-10 | 2011-12-22 | Japan Superconductor Technology Inc | Superconducting magnet device |
| JP2013108986A (en) * | 2011-11-20 | 2013-06-06 | Krohne Ag | Magnetization device for nuclear magnetic flowmeter |
| WO2014203190A1 (en) * | 2013-06-21 | 2014-12-24 | Koninklijke Philips N.V. | Shim system for a magnetic resonance hybrid scanner |
-
1988
- 1988-04-01 JP JP63078123A patent/JPH01254154A/en active Pending
Cited By (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH07250819A (en) * | 1991-12-19 | 1995-10-03 | General Electric Co <Ge> | Side approach picture forming magnet wherein shim is passively applied |
| JP2007526058A (en) * | 2004-03-05 | 2007-09-13 | シーメンス アクチエンゲゼルシヤフト | Magnetic field adjustment device |
| US7683624B2 (en) | 2007-05-25 | 2010-03-23 | Mitsubishi Electric Corporation | Magnetic field adjustment device and magnetic field adjustment method for superconducting magnet |
| WO2011122403A1 (en) * | 2010-03-30 | 2011-10-06 | ジャパンスーパーコンダクタテクノロジー株式会社 | Superconducting magnet device |
| JP2011255027A (en) * | 2010-06-10 | 2011-12-22 | Japan Superconductor Technology Inc | Superconducting magnet device |
| JP2013108986A (en) * | 2011-11-20 | 2013-06-06 | Krohne Ag | Magnetization device for nuclear magnetic flowmeter |
| WO2014203190A1 (en) * | 2013-06-21 | 2014-12-24 | Koninklijke Philips N.V. | Shim system for a magnetic resonance hybrid scanner |
| US10661098B2 (en) | 2013-06-21 | 2020-05-26 | Koninklijke Philips N.V. | Shim system for a magnetic resonance hybrid scanner |
| US11291860B2 (en) | 2013-06-21 | 2022-04-05 | Koninklijke Philips N.V. | Shim system for a magnetic resonance hybrid scanner |
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