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11.发明授权公开(公告)号：US06438967B1
公开(公告)日：2002-08-27
申请号：US09915916
申请日：2001-07-26
IPC分类号： F25B900
CPC分类号： F25D19/006 , F25B9/10 , H01F6/04
摘要： A method for cooling a superconducting device by using a sleeve assembly which thermally interconnects a two stage cryocooler with the device. In operation, the cryocooler is moveable relative to the sleeve assembly between a first configuration wherein the cryocooler is engaged with the sleeve assembly, and a second configuration wherein the cryocooler is disengaged from the sleeve assembly. The cryocooler is disposed in the sleeve assembly with the cooling element of the cryocooler positioned at a distance from the cylinder of the sleeve assembly to establish thermal communication therebetween. Also, the cooling probe of the cryocooler is in contact with the receptacle of the sleeve assembly and is urged against the receptacle to establish thermal communication therebetween. A bellows joins the cryocooler with the sleeve assembly to create an enclosed chamber therebetween and helium is pumped into the sleeve assembly to maintain an operational pressure in the sleeve assembly.
摘要翻译： 一种通过使用将两级制冷器与设备热互连的套筒组件来冷却超导装置的方法。 在操作中，低温冷却器可相对于套筒组件在第一构型和第二构造之间移动，第一配置是低温冷却器与套筒组件接合，以及第二构造，其中低温冷却器与套筒组件脱离接合。 低温冷却器设置在套筒组件中，低温冷却器的冷却元件位于与套筒组件的气缸一定距离处，以在它们之间建立热连通。 此外，低温冷却器的冷却探针与套筒组件的容器接触并且被推靠在容器上以在它们之间建立热连通。 波纹管将低温冷却器与套筒组件连接以在其间形成封闭的腔室，并且将氦泵送到套筒组件中以保持套筒组件中的操作压力。
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公开(公告)号：US4980641A
公开(公告)日：1990-12-25
申请号：US393400
申请日：1989-08-11
IPC分类号： G01R33/38 , G01R33/383 , G01R33/385 , G01R33/421
CPC分类号： G01R33/421 , G01R33/3806 , G01R33/383 , G01R33/385
摘要： An apparatus for minimizing hysteresis in a magnetic resonance imaging device of the type utilizing a pair of oppositely charged parallel pole faces forming a magnetic field therebetween, and gradient coils spaced apart from each pole face for producing time varying magnetic fields, comprises a layer of nonferromagnetic conducting material interposed between the pole face and the gradient coil. The interposed layer carries eddy currents induced by time varying magnetic fields produced by the gradient coils, thereby minimizing AC induced eddy current hysteresis from the pole faces. The layer preferably has a thickness of at least one skin depth at the frequency associated with the time varying magnetic field. The layer is preferably contiguous with the pole face, and comprises copper or aluminum. In another embodiment, each pole face has a plurality of slits therethrough radiating inward from the circumference for eliminating the eddy currents in the pole face. The slits in one pole face are preferably symmetrical to those in the other. There are preferably twenty-four (24) slits spaced fifteen degrees (15.degree.) apart. There is also disclosed the method for accomplishing the same.
摘要翻译： 一种用于最小化磁共振成像装置中的磁滞的装置，该磁共振成像装置利用在它们之间形成磁场的一对相反电荷的平行极面以及与每个极面间隔开的用于产生时变磁场的梯度线圈，包括非铁磁层 介于极面和梯度线圈之间的导电材料。 插入层承载由梯度线圈产生的由时变磁场引起的涡流，从而最小化从极面引起的AC感应涡流滞后。 该层优选地具有与时变磁场相关联的频率处的至少一个皮肤深度的厚度。 该层优选与极面相邻，并且包括铜或铝。 在另一个实施例中，每个极面具有从圆周向内辐射的多个狭缝，以消除极面中的涡流。 一个极面中的狭缝优选地与另一个极面对应。 优选分开间隔十五度（15°）的二十四（24）个狭缝。 还公开了实现该方法的方法。
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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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公开(公告)号：US5047192A
公开(公告)日：1991-09-10
申请号：US377314
申请日：1989-07-10
CPC分类号： F25B9/14 , F02G1/057 , F25B2309/003
摘要： Process of manufacturing a cryogenic regenerator including a plurality of channels for conducting a working fluid, including the steps of providing a cylindrical forming member having a longitudinal axis and a plurality of peripheral slots displaced axially and oriented substantially parallel to the longitudinal axis of the cylindrical forming member, or having a continuous spiral peripheral slot of sufficiently small pitch such that the convolutions thereof are oriented substantially parallel to such longitudinal axis; providing epoxy which is relatively flexible upon hardening, loading the epoxy with thermally conductive material for enhancing the radial thermal conductivity of the cryogenic regenerator, and applying the epoxy to the periphery of the cylindrical forming member to fill the plurality of slots or the spiral peripheral slot with the epoxy and to form a radial layer of the epoxy of a generally first radial thickness allowing the epoxy to harden and thereafter reducing the radial thickness of the peripheral layer of hardened epoxy to a second smaller radial thickness; splitting the hardened relatively flexible epoxy radially and parallel to the axis and thereafter removing the epoxy from the cylindrical forming member to provide a relatively flexible base layer from the epoxy formerly residing on the periphery of the cylindrical forming member and to provide a plurality of substantially parallel corrugations from epoxy formerly residing in the plurality of slots or the spiral peripheral slot, the corrugations extending outwardly from a bottom of the base layer; and rolling the relatively flexible base layer into a generally cylindrical spiral having an axis with the corrugations extending parallel to the axis of the cylindrical spiral and with the corrugations extending radially inwardly and engaging a top of the base layer to cause the base layer and the corrugations to cooperatively form the plurality of channels.
摘要翻译： 制造包括用于传导工作流体的多个通道的低温再生器的方法，包括以下步骤：提供具有纵向轴线的圆柱形成型构件和沿轴向位移并基本上平行于圆柱形成型件的纵向轴线定向的多个周向槽 或者具有足够小间距的连续螺旋形周边槽，使得其卷积基本上平行于该纵向轴线定向; 提供在硬化时相对柔性的环氧树脂，用导热材料加载环氧树脂以增强低温再生器的径向热导率，以及将环氧树脂施加到圆柱形成形构件的周边以填充多个槽或螺旋形外周槽 与环氧树脂形成通常第一径向厚度的环氧树脂的径向层，从而允许环氧树脂硬化，然后将硬化环氧树脂周边层的径向厚度减小到第二较小的径向厚度; 将硬化的相对柔性的环氧树脂径向和平行于轴线分裂，然后从圆柱形成型构件中除去环氧树脂，从而形成相对柔性的基层，该基层先前位于圆柱形成形构件的周边上，并提供多个基本平行的 波纹从原来位于多个槽或螺旋周边槽中的环氧树脂，波纹从基层的底部向外延伸; 并且将相对柔性的基层滚动成具有轴线的大致圆柱形螺旋，其中波纹平行于圆柱形螺旋的轴线延伸，并且波纹径向向内延伸并且接合基底层的顶部，以使基底层和波纹 协同地形成多个信道。
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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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