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公开(公告)号：US4743880A
公开(公告)日：1988-05-10
申请号：US101518
申请日：1987-09-28
IPC分类号： A61B10/00 , A61B5/055 , G01R33/20 , G01R33/3815 , G01R33/421 , H01F7/20 , H01F7/00
CPC分类号： G01R33/3815 , G01R33/421
摘要： A magnet system for providing a localized, substantially homogeneous field for use in medical magnetic resonance imaging and its incorporation into a method of siting. The magnet system includes a vacuum vessel defining a bore for receiving the subject of the imaging and having a first end and a second end. A cryogenic containment vessel is supported within the vacuum vessel and a single coil is disposed within the containment vessel for providing the magnetic field. The magnetic system also includes a shield assembly of ferromagnetic material positioned closely adjacent the outside of the vacuum vessel and including first and second end assemblies and a plurality of axially extending beam-like members interconnecting the end assemblies. The coil comprises a winding made up of thousands of turns of small superconductive wire and which is configured to compensate for the effect of the presence of the shield to provide the substantially homogeneous field at a predetermined location in the bore. The components of the shield assembly are adapted for mounting to said vacuum vessel after siting. This permits simplified siting of the magnet system in that the vacuum vessel with the components inside of it can be sited first and the components of the shield assembly thereafter mounted on the vacuum vessel. A method of manufacturing the magnet system is also disclosed.
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公开(公告)号：US4841268A
公开(公告)日：1989-06-20
申请号：US101517
申请日：1987-09-28
CPC分类号： H01F6/065 , G01R33/3815 , G01R33/3804
摘要： A magnet system, having permanently installed power leads, for providing a magnetic field. The system includes a vacuum vessel and a cryogenic containment vessel supported within the vacuum vessel. The containment vessel holds a main coil formed of superconductive wire, along with a quantity of liquid helium to maintain the wire below its critical temperature. The power leads, which supply energy to the coil from a power supply outside the vacuum vessel, also take energy from the coil to a load resistor outside the vacuum vessel when the coil is discharged, each include an elongate metallic tube. The magnet system also includes a solenoid controlled valve which is responsive to the passage of electric current through the tubes of the power leads to cause helium gas resulting from the boiling of liquid helium in the containment vessel to be vented to atmosphere through the tube thereby cooling them.
摘要翻译： 磁体系统，永久地安装电源线，用于提供磁场。 该系统包括真空容器和支撑在真空容器内的低温容纳容器。 安全壳容纳由超导线形成的主线圈以及一定量的液氦，以将线保持在其临界温度以下。 从真空容器外部的电源向线圈供给能量的电源线，当线圈被排出时，也将能量从线圈吸收到真空容器外部的负载电阻上，每个电源都包括细长的金属管。 磁体系统还包括电磁控制阀，其响应于通过电力引线的管的电流的通过，导致由安全壳中的液氦沸腾产生的氦气通过管排出到大气中，从而冷却 他们。
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公开(公告)号：US4768008A
公开(公告)日：1988-08-30
申请号：US80020
申请日：1987-07-31
IPC分类号： A61B10/00 , A61B5/055 , G01R33/381 , G01R33/3815 , H01F7/20 , H01F7/22
CPC分类号： G01R33/3815
摘要： A magnet system for use in magnetic resonance imaging. The system includes a vacuum vessel having a first wall assembly defining a bore for receiving the subject of the imaging and a pair of spaced metallic end plates welded to the ends of the first wall assembly. The system further includes a cryogenic containment vessel supported within the vacuum vessel and a coil disposed within the containment vessel for providing the magnetic field. The first wall assembly includes a weldable metallic cylindrical shell positioned intermediate the end plates and having a thickness insufficient without reinforcement to provide structural integrity during operation of the vacuum vessel. This first wall assembly further includes a reinforcement layer of a non-metallic material disposed about the metallic shell so that signals provided by gradient coils disposed inside the bore can more quickly penetrate the first wall assembly than if the metallic shell had sufficient thickness, without reinforcement to provide the necessary structural integrity.
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4.发明授权Magnetic resonance imaging magnet having minimally symmetric ferromagnetic shield 失效具有最小对称铁磁屏蔽的磁共振成像磁体
公开(公告)号：US4931759A
公开(公告)日：1990-06-05
申请号：US334291
申请日：1989-04-06
IPC分类号： G01R33/387 , A61B5/055 , G01R33/3815 , G01R33/3873 , G01R33/421
CPC分类号： G01R33/421 , G01R33/3815 , G01R33/3873
摘要： A magnetic resonance imaging magnet has a solenoidal superconducting winding producing a magnetic field and defining an examination region within a bore thereof. The examination region receives a body to be examined. The solenoidal superconducting winding generates a quasi-static magnetic field for aligning atomic nuclei in the body being examined. A two-fold or minimally symmetric ferromagnetic shield has a pair of magnetic flux return paths positioned on opposite sides of the solenoidal superconducting winding for reducing the magnetic field intensity in a region proximate to and outside of the solenoidal superconducting winding. A magnetic field inhomogeneity compensating system reduces magnetic field inhomogeneities introduced into the magnetic field within the examination region by the minimally symmetric ferromagnetic shield to provide a highly uniform quasi-static magnetic field within the examination region.
摘要翻译： 磁共振成像磁体具有产生磁场的螺线管超导绕组并且在其孔内限定检查区域。 检查区域接受检查的身体。 螺线管超导绕组产生准静态磁场，用于对准被检体内的原子核。 双重或最小对称的铁磁屏蔽具有位于螺线管超导绕组的相对侧上的一对磁通返回路径，用于减小靠近和超出螺线管超导绕组的区域内的磁场强度。 磁场不均匀性补偿系统通过最小对称的铁磁屏蔽减小引入到检查区域内的磁场的磁场不均匀性，以在检查区域内提供高度均匀的准静态磁场。
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5.发明授权
公开(公告)号：US5194810A
公开(公告)日：1993-03-16
申请号：US813981
申请日：1991-12-26
IPC分类号： G01R33/383 , G01R33/3873 , H01F7/02
CPC分类号： G01R33/383 , G01R33/3873 , H01F7/0278
摘要： An open access superconducting MRI magnet includes a ferromagnetic frame open on at least two sides and having upper and lower end plates and at least two support posts. A superconducting coil assembly is mounted to each end plate for generating a magnetic flux field in a patient receiving area located between the end plates. A magnetic flux field shaping means is associated with each end plate. The flux field shaping means includes rose shims, inner rings mounted within the rose shims, and removable segments mounted to the rose shims. Transition plates are located between the support ports and end plates for minimizing flux leakage. In addition the end plates are formed with a varying thickness such that a cross section taken perpendicular to a return path of magnetic flux is substantially constant.
摘要翻译： 开放式超导MRI磁体包括在至少两个侧面上开放的铁磁框架，并且具有上端板和下端板以及至少两个支撑柱。 超导线圈组件安装到每个端板，用于在位于端板之间的患者接收区域中产生磁通场。 磁通量场成形装置与每个端板相关联。 通量场成形装置包括玫瑰垫片，安装在玫瑰垫片内的内圈和安装在玫瑰垫片上的可拆卸部分。 过渡板位于支撑端口和端板之间，以最小化漏磁。 此外，端板形成为具有变化的厚度，使得垂直于磁通的返回路径取得的横截面基本上是恒定的。
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公开(公告)号：US06438966B1
公开(公告)日：2002-08-27
申请号：US09881642
申请日：2001-06-13
IPC分类号： F25B900
CPC分类号： F25D19/006 , F25B9/10 , H01F6/04
摘要： A sleeve assembly for thermally interconnecting a pulse tube, two stage cryocooler with a superconducting device includes a heat transfer cylinder, a heat transfer receptacle and a wall extending therebetween to define a passageway. The heat transfer receptacle is formed with a tapered recess wherein a tapered cooling probe of the cryocooler is urged against the heat transfer receptacle to establish thermal communication therebetween. A cooling element of the cryocooler is disposed in the heat transfer cylinder to establish thermal communication therebetween. In operation, the cryocooler moves relative to the sleeve assembly between a first configuration wherein the cryocooler is engaged with the sleeve assembly to establish thermal communication therebetween and a second configuration wherein the cryocooler is disengaged with the sleeve assembly. An expandable bellows which interconnects the cryocooler with the sleeve assembly will maintain thermal insulation therebetween when the cryocooler is disengaged from the sleeve assembly.
摘要翻译： 用于将脉冲管，两级制冷器与超导装置热互连的套筒组件包括传热圆筒，传热容器和在其间延伸以限定通道的壁。 传热容器形成有锥形凹槽，其中低温冷却器的锥形冷却探针被推靠在传热容器上以在它们之间建立热连通。 低温冷却器的冷却元件设置在传热圆筒中，以在它们之间建立热连通。 在操作中，低温冷却器相对于套筒组件在第一配置之间移动，其中低温冷却器与套筒组件接合以在其间建立热连通，而第二配置，其中低温冷却器与套筒组件分离。 将低温冷却器与套管组件相互连接的可膨胀波纹管在低温冷却器与套筒组件脱离接合时将保持其间的热绝缘。
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公开(公告)号：US4782671A
公开(公告)日：1988-11-08
申请号：US101516
申请日：1987-09-28
IPC分类号： A61B10/00 , A61B5/055 , F17C3/08 , F25J1/00 , G01R33/20 , G01R33/38 , G01R33/3815 , H01F7/20 , H01L39/00 , H05K9/00 , F25B19/00
CPC分类号： F25J1/0276 , F17C3/085 , G01R33/3815 , F17C2201/0119 , F17C2203/0312 , F17C2203/032 , F17C2203/0391 , F17C2221/014 , F17C2221/017 , F17C2223/0161 , F17C2223/033 , F17C2227/0341 , F17C2265/034 , F17C2270/0509 , F17C2270/0536 , F25J2290/42
摘要： An improvement in cooling apparatus in a magnet system for providing a localized, substantially homogeneous magnetic field for use in magnetic resonance imaging. The magnet system includes a vacuum vessel, a cryogenic containment vessel inside the vacuum vessel and having a coil of superconductive wire along with a quantity of liquid helium to maintain the wire below its critical temperature. The system also includes an inner thermal radiation shield between the containment vessel and the vacuum vessel and an outer thermal radiation shield between the inner shield and the vacuum vessel. A cryogenic refrigerator is supported by the vacuum vessel and extends inside. This refrigerator has a first-stage heat station cooling the outer shield and second-stage heat station for cooling the inner shield. The improvement includes the provision of a tank holding a quantity of liquid nitrogen. This tank is supported in good heat transfer relationship with the first-stage heat station between the vacuum vessel and the outer shield and is spaced from the outer shield. Tubing is provided for transferring the liquid nitrogen from the tank so that it boils in good heat transfer relationship with the outer shield and also returns gas resulting from the boiling of the liquid nitrogen back to the tank where the refrigerator condenses it in the tank. A method of using the cooling apparatus in the event the refrigerator is not functional, is also disclosed.
摘要翻译： 用于提供用于磁共振成像的局部的，基本均匀的磁场的磁体系统中的冷却装置的改进。 磁体系统包括真空容器，真空容器内部的低温容纳容器，并且具有一束超导线以及一定量的液氦，以将电线保持在其临界温度以下。 该系统还包括在容纳容器和真空容器之间的内部热辐射屏蔽以及内部屏蔽和真空容器之间的外部热辐射屏蔽。 低温冰箱由真空容器支撑并在内部延伸。 该冰箱具有冷却外屏蔽的第一级加热站和用于冷却内屏蔽的第二级加热站。 改进之处在于提供容纳液氮的罐。 该罐与真空容器和外罩之间的第一级加热站具有良好的传热关系，并与外护罩间隔开。 提供管道用于从罐转移液氮，使得其与外部屏蔽件具有良好的热传递关系，并且将从液氮的沸腾产生的气体返回到罐中，其中冰箱将其冷凝在罐中。 还公开了在冰箱不起作用的情况下使用冷却装置的方法。
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8.发明授权MRI magnet and MRI system with optimized fringe fields, attractive forces and spatial constraints 有权MRI磁体和MRI系统具有优化的边缘场，吸引力和空间限制公开(公告)号：US08729899B2
公开(公告)日：2014-05-20
申请号：US13178805
申请日：2011-07-08
IPC分类号： G01V3/00
CPC分类号： G01R33/421
摘要： A magnetic resonance imaging (MRI) system magnet includes at least one main electromagnet winding disposed within a first radius of the magnet and at least one bucking electromagnet winding disposed within a second radius, larger than the first radius of the magnet and configured to provide self-shielding magnetic fields that substantially reduce fringe magnetic fields outside the magnet produced by the main electromagnet winding. The combination of magnetic fields produced by both the main and bucking electromagnet windings inside the magnet conform to MRI requirements within at least an imaging volume. The main and bucking electro-magnet windings are configured so as to create a net fringe field outside the magnet within the range of 50-100 gauss at a distance within a range of 3-5 meters axially and 2-3 meters radially from a center of the magnet.
摘要翻译： 磁共振成像（MRI）系统磁体包括设置在磁体的第一半径内的至少一个主电磁体绕组和设置在第二半径内的至少一个屈曲电磁体绕组，其大于磁体的第一半径并且被配置为提供自身 所述磁场基本上减少由主电磁铁绕组产生的磁体外的边缘磁场。 磁体内部的主电磁铁和屈曲电磁铁绕组产生的磁场的组合符合至少一个成像体积内的MRI要求。 主电磁铁绕组被构造成在50-100高斯的范围内在磁体外部产生一个净边缘场，距离在3-5米的范围内，距中心径向2-3米 的磁铁。
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9.发明申请MRI MAGNET AND MRI SYSTEM WITH OPTIMIZED FRINGE FIELDS, ATTRACTIVE FORCES AND SPATIAL CONSTRAINTS 有权具有优化的FRINGE字段，吸引力和空间约束的MRI磁体和MRI系统公开(公告)号：US20130009642A1
公开(公告)日：2013-01-10
申请号：US13178805
申请日：2011-07-08
IPC分类号： G01R33/44
CPC分类号： G01R33/421
摘要： A magnetic resonance imaging (MRI) system magnet includes at least one main electromagnet winding disposed within a first radius of the magnet and at least one bucking electromagnet winding disposed within a second radius, larger than the first radius of the magnet and configured to provide self-shielding magnetic fields that substantially reduce fringe magnetic fields outside the magnet produced by the main electromagnet winding. The combination of magnetic fields produced by both the main and bucking electromagnet windings inside the magnet conform to MRI requirements within at least an imaging volume. The main and bucking electro-magnet windings are configured so as to create a net fringe field outside the magnet within the range of 50-100 gauss at a distance within a range of 3-5 meters axially and 2-3 meters radially from a center of the magnet.
摘要翻译： 磁共振成像（MRI）系统磁体包括设置在磁体的第一半径内的至少一个主电磁体绕组和设置在第二半径内的至少一个屈曲电磁体绕组，其大于磁体的第一半径并且被配置为提供自身 所述磁场基本上减少由主电磁铁绕组产生的磁体外的边缘磁场。 磁体内部的主电磁铁和屈曲电磁铁绕组产生的磁场的组合符合至少一个成像体积内的MRI要求。 主电磁铁绕组被构造成在50-100高斯的范围内在磁体外部产生一个净边缘场，距离在3-5米的范围内，距中心径向2-3米 的磁铁。
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10.发明授权MRI system with side-access to an image volume located within a two-column main magnet 失效MRI系统具有对位于两列主磁体内的图像体积的侧面访问
公开(公告)号：US5517121A
公开(公告)日：1996-05-14
申请号：US372345
申请日：1995-01-13
申请人： Leon Kaufman , Jianhua Li , Joseph W. Carlson , Bruce C. Breneman
发明人： Leon Kaufman , Jianhua Li , Joseph W. Carlson , Bruce C. Breneman
CPC分类号： G01R33/3806
摘要： Convenient side access to an image volume located within a two-pole, two-column main magnet of an MRI system is provided by rotating the symmetry axis of the magnet to be non-perpendicular with respect to the longitudinal axis of the patient transport and/or otherwise displacing the two column structures of the magnetic circuit so as to permit open and unobstructed access to the image volume along a direction perpendicular to the longitudinal axis of the patient transport.
摘要翻译： 通过使磁体的对称轴相对于患者输送的纵向轴线旋转而不对称地提供位于MRI系统的两极双列主磁体内的图像体积的便利侧进入和/ 或以其它方式移位磁路的两个列结构，以允许沿垂直于患者输送的纵向轴线的方向打开和畅通无阻地访问图像体积。
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