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1.发明授权Methods and apparatus for reducing heat introduced into superconducting systems by electrical leads 失效用于通过电引线减少引入超导体系的热的方法和装置
公开(公告)号：US4369636A
公开(公告)日：1983-01-25
申请号：US280325
申请日：1981-07-06
CPC分类号： H02G15/34 , H01F6/04 , Y02E40/648 , Y10S505/892
摘要： Methods and apparatus are provided for minimizing heat introduced by electrical leads into the cryogenic liquid in which a superconducting magnet is immersed. The electrical leads have normal portions extending from exterior of the cryogenic liquid containment vessel and thereinto and superconducting portions extending vertically downward therefrom and connected to the magnet. Means are provided to lower and raise the level of cryogenic liquid around the superconducting portions of the leads to fully immerse the supercoducting portions during periods of magnet energization and expose selected segments thereof when the magnet is de-energized. When exposed, the non-immersed segments provide a thermal resistance between the normal metal portions and the cryogenic liquid.
摘要翻译： 提供的方法和装置用于最小化电导线引入浸入超导磁体的低温液体中的热量。 电引线具有从低温液体容纳容器的外部延伸的正常部分和从其垂直向下延伸并连接到磁体的超导部分。 提供了用于降低和提高引线的超导部分周围的低温液体的水平，以在磁体通电期间完全浸入超导部分，并在磁体断电时暴露其选定的部分。 当暴露时，非浸没段在正常金属部分和低温液体之间提供热阻。
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2.发明授权
公开(公告)号：US4658229A
公开(公告)日：1987-04-14
申请号：US733232
申请日：1985-05-10
申请人： Wilkie Y. Chen , Yen-Hwa L. Hsu , John R. Purcell
发明人： Wilkie Y. Chen , Yen-Hwa L. Hsu , John R. Purcell
IPC分类号： G01R33/3815 , G01R33/3875 , H01F7/22
CPC分类号： G01R33/3815 , G01R33/3875 , Y10S505/879
摘要： A magnet system for providing a substantially homogeneous magnetic field in a region. The magnet system includes a main coil and a pair of correcting coils with the main coil generating a magnetic field in a zone including the region. The correcting coils are at first and second locations in the zone and are connected to one another so that a magnetic field generated by the main coil will induce currents in the correcting coils which oppose one another. The correcting coils are constructed so that there will be no resultant current in them when there is generated substantially the same field strength of both of the first and second locations. Thus, the generation of differing magnetic field strengths at the respective locations effects generation of a resultant current in the correcting coil causing strengthening of the magnetic field at the location having the lesser magnetic field strength and weakening of the magnetic field at the other location, making the net field relatively homogeneous.
摘要翻译： 一种用于在区域中提供基本均匀的磁场的磁体系统。 磁体系统包括主线圈和一对校正线圈，其中主线圈在包括该区域的区域中产生磁场。 校正线圈位于区域中的第一和第二位置处并且彼此连接，使得由主线圈产生的磁场将引起彼此相对的校正线圈中的电流。 校正线圈被构造成使得当第一位置和第二位置都产生基本上相同的场强时，在其中将不存在合成电流。 因此，在各个位置处产生不同的磁场强度会影响校正线圈中的合成电流的产生，从而在具有较小磁场强度的位置处增强磁场并使另一位置处的磁场变弱 净场相对均匀。
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3.发明授权
公开(公告)号：US5148137A
公开(公告)日：1992-09-15
申请号：US669804
申请日：1991-03-15
CPC分类号： B03C1/0337 , H01F6/04 , Y10S505/898
摘要： A cryogenic containment vessel for use with a pulsed superconducting magnet system includes a superconducting coil positioned within the cryogenic containment vessel for providing a magnetic field. The containment vessel includes a relatively thin metallic inner tube for holding liquid helium and the coil. The containment vessel also includes a relatively thick outer tube encompassing the inner tube with a relatively rigid insulative spacer positioned between the inner and outer tubes so that the tubes are not in contact with each other. The outer tube is predominantly metallic and has at least one joint formed of insulative material to prevent the outer tube from forming a low electrical resistance loop. The inner tube provides a vacuum seal and the outer tube provides structural support for the inner tube so that eddy current losses resulting from ramping of the current to the coil are reduced. A method of fabricating the containment vessel is also disclosed.
摘要翻译： 用于脉冲超导磁体系统的低温容纳容器包括位于低温容纳容器内的用于提供磁场的超导线圈。 安全壳包括用于保持液氦和线圈的相对薄的金属内管。 容纳容器还包括相对较厚的外管，其包围内管，其具有定位在内管和外管之间的相对刚性的绝缘间隔件，使得管不彼此接触。 外管主要是金属的，并且具有由绝缘材料形成的至少一个接头，以防止外管形成低电阻回路。 内管提供真空密封，外管为内管提供结构支撑，从而降低了电流向线圈斜坡所引起的涡流损耗。 还公开了一种制造安全壳的方法。
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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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5.发明授权
公开(公告)号：US4528609A
公开(公告)日：1985-07-09
申请号：US410499
申请日：1982-08-23
申请人： John R. Purcell
发明人： John R. Purcell
IPC分类号： H02H7/00
CPC分类号： H02H7/001 , Y02E40/68 , Y10S505/85
摘要： A method and apparatus are provided for protecting a superconducting magnetic energy storage system having a coil from damage caused by a change of state of at least a portion of the coil from superconducting to normal conducting, and the consequent conversion of stored electrical energy to heat. A thermal capacitance is placed in thermal contact with the coil. The thermal capacitance is formed of a substance, such as nitrogen, which is solid at operating pressure at a temperature substantially above the transition temperature of the coil and that vaporizes below the temperature at which the system is damaged. The volume of the substance is sufficient to provide thermal capacity upon vaporization of the substance to dissipate substantially all of the stored energy without permitting the system to overheat. Liquid helium is provided in thermal contact with the substance and the coil for normally cooling the coil and the thermal capacitance to a temperature which is low enough so that the coil is in its superconducting state and the substance becomes substantially solid. Means are also provided for propagating any normal conducting region that is present for more than a very short time over substantially all of the coil by removing the helium from thermal contact with a substantial portion of the coil. In this manner, the substance absorbs the stored energy while maintaining the temperature of the system below the temperature at which it is damaged.
摘要翻译： 提供了一种方法和装置，用于保护具有线圈的超导磁能存储系统免受由线圈的至少一部分状态从超导到正常导通的状态改变的损害，以及由此将存储的电能转换成热。 热电容放置在与线圈热接触的位置。 热电容由诸如氮的物质形成，其在基本上高于线圈的转变温度的温度的操作压力下是固体的，并且在系统损坏的温度以下蒸发。 物质的体积足以在物质蒸发时提供热容量，以消散基本上所有储存的能量，而不允许系统过热。 提供与物质和线圈热接触的液氦，用于将线圈和热电容正常冷却到足够低的温度，使得线圈处于其超导状态并且物质变得基本上是固体的。 还提供了用于通过除去氦与线圈的大部分热接触来传播在基本上所有线圈上存在超过非常短的时间的任何正常导电区域的装置。 以这种方式，物质吸收储存的能量，同时保持系统的温度低于其损坏的温度。
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公开(公告)号：US4930314A
公开(公告)日：1990-06-05
申请号：US404605
申请日：1989-09-08
IPC分类号： F25B9/14
CPC分类号： F25B9/14 , F02G2253/06 , F02G2253/08
摘要： Improved Stirling cycle machine including at least a pair of eccentric disks fixed to a pair of rotatable shafts in phase with each other and which eccentric disks upon rotation of the shafts (in opposite directions in the preferred embodiment) also rotate (in opposite directions in the preferred embodiment) and impart upward movement to a bellows defining a variable-volume compression or expansion chamber with a reduced tendency to also impart side thrust, rocking motion, or lateral movement to the bellows whereby bellows wear is reduced and the life of the bellows and the Stirling cycle machine is increased.
摘要翻译： 改进的斯特林循环机包括至少一对固定在一对可转动的轴上的偏心盘，它们彼此同相，并且在轴（在优选实施例中沿相反方向）转动时，偏心盘也旋转 优选实施例），并且将向上运动赋予限定可变容积的压缩或膨胀室的波纹管，同时具有降低的倾向，从而使侧向推力，摆动运动或向波纹管的侧向运动，从而降低波纹管磨损，并且波纹管和 斯特林循环机增加。
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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：US4680936A
公开(公告)日：1987-07-21
申请号：US813175
申请日：1985-12-24
CPC分类号： F17C3/08 , F17C3/10 , F25D3/10 , G01R33/3815 , H01F6/04 , F17C2201/0119 , F17C2203/03 , F17C2203/0687 , F17C2221/017 , F17C2221/038 , F17C2223/0161 , F17C2227/0353 , F17C2227/045
摘要： According to the present invention, improved cryogenic magnet systems for use in MRI devices are provided. These systems comprise an electromagnet immersed in a first tank containing a first liquefied gas. The first tank is located in an evacuated container that is evacuated to a high vacuum. A refrigerating system external to said evacuated container includes a second gas and a means for liquefying said second gas. A heat radiation shield means surrounding said first tank is cooled by the liquified second gas. Features of the invention include a thermal siphon for cooling the heat radiation shield and neon as the second gas.
摘要翻译： 根据本发明，提供了用于MRI装置的改进的低温磁体系统。 这些系统包括浸入包含第一液化气体的第一罐中的电磁体。 第一个罐位于抽真空至高真空的真空容器中。 所述真空容器外部的制冷系统包括第二气体和用于液化所述第二气体的装置。 围绕所述第一罐的散热屏蔽装置被液化的第二气体冷却。 本发明的特征包括用于冷却热辐射屏蔽的热虹吸和作为第二气体的氖。
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公开(公告)号：USRE36332E
公开(公告)日：1999-10-12
申请号：US33946
申请日：1998-03-02
CPC分类号： F25B25/005 , H01F6/04
摘要： A refrigeration system includes a dewar and a refrigerator/liquefier which meets the variable demands of a superconducting magnet within the dewar. The system is sized to meet average loads over a defined duty cycle, and is variably operable to meed demands. In the preferred embodiment, a first supply of fluid circulates through a "condenser" element positioned in a dewar ullage to liquefy a separate supply of fluid in the dewar, and to refrigerate a pulsed cryogenic load therein, such as a superconducting magnet. A portion of the first supply of fluid may be diverted to refrigerate a second pulsed cryogenic load, such as magnet current leads permanently connected to the magnet. The dewar includes a cold gas vapor storage chamber separate from the dewar ullage, and the chamber is preferably located within the inner core of a solenoid superconducting magnet for compact and thermally efficient design. Responsive, independent adjustment of refrigeration to pulsed cryogenic loads is made possible.
摘要翻译： 制冷系统包括杜瓦瓶和冰箱/液化器，其满足杜瓦瓶内的超导磁体的可变需求。 该系统的尺寸适合于在规定的工作周期内满足平均负载，并且可变地可操作以满足需求。 在优选实施例中，第一流体供应通过位于杜瓦瓶中的“冷凝器”元件循环，以液化杜瓦瓶中的单独的液体供应，并使其中的脉冲低温负载（例如超导磁体）冷藏。 第一流体供应的一部分可以被转向以冷却第二脉冲低温负载，例如永久地连接到磁体的磁体电流引线。 杜瓦瓶包括与杜瓦瓶分离的冷气体蒸气储存室，腔室优选位于螺线管超导磁体的内芯内，用于紧凑和热效率的设计。 对脉冲低温负载进行制冷的独立调整成为可能。
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公开(公告)号：US4866943A
公开(公告)日：1989-09-19
申请号：US258504
申请日：1988-10-17
CPC分类号： F02G1/057 , F25B9/14 , F25B2309/003
摘要： Cryogenic regenerator formed by a spirally rolled, flexible composite material including a base layer having a top and a bottom provided with a plurality of spaced, substantially parallel corrugations extending outwardly therefrom and wherein the flexible base layer is rolled into a generally cylindrical spiral with the corrugations extending radially inwardly and engaging the top of the base layer to cause the base layer and the corrugations to cooperatively form a plurality of channels for conducting the working fluid through the regenerator. The relatively flexible composite material may be a relatively flexible, hardened epoxy; the composite material may be loaded with thermally conductive material and may be an epoxy loaded with thermally conductive material. The depth or transverse cross-sectional area of the regenerator channels may continuously decrease from the hot end to the cold end of the regenerator to reduce the working fluid volume in the regenerator and to decrease the pressure drop across the regenerator by providing an improved match between the density of the working fluid and the depth or transverse cross-sectional area of the regenerator channels from the hot end towards the cold end.
摘要翻译： 由螺旋卷绕的柔性复合材料形成的低温再生器，其包括具有顶部和底部的基底层，所述基底层具有从其向外延伸的多个间隔开的基本平行的波纹，并且其中柔性基底层被卷成具有波纹的大致圆柱形螺旋 径向向内延伸并与基底层的顶部接合以使基底层和波纹协同地形成用于通过再生器传导工作流体的多个通道。 相对柔性的复合材料可以是相对柔性的，硬化的环氧树脂; 复合材料可以装载有导热材料，并且可以是负载有导热材料的环氧树脂。 再生器通道的深度或横截面积可以从再生器的热端到冷端连续地减小，以减少再生器中的工作流体体积，并且通过提供改进的匹配 工作流体的密度以及从热端到冷端的再生器通道的深度或横截面积。
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