Abstract: A cooling fluid coupling is disclosed for providing cooling fluid to a rotor having a super-conducting winding of a synchronous machine and a source of cryogenic cooling fluid. The fluid coupling comprises an inlet cooling tube and an outlet cooling tube in the rotor and coaxial with an axis of the rotor. The inlet cooling tube has an input port coupled to receive inlet cooling fluid from the source of cryogenic cooling fluid. The outlet cooling tube has an output port coupled to return cooling fluid from the rotor to source. A stationary motion gap seal separates the input port and output port of the coupling.

Abstract: A magnet, such as an open magnetic-resonance-imaging (MRI) magnet) has a first assembly including a superconductive main coil and a magnetizable pole piece which, during magnet operation, has a temperature equal to generally the temperature of the main coil. In one example, a cryogenic-fluid (e.g., liquid helium) dewar encloses the main coil, and the dewar has an interior surface defined in part by a surface portion of the pole piece. A method for providing a homogeneous imaging volume for a magnet includes steps to construct the above-described magnet.

Abstract: A laminated composite shell assembly includes composite shells assembled together and having joint bonds connecting the assembly with an external structure and pinch rings assembled to the shells adjacent the joint bonds so as to reinforce the same. The composite shells and pinch rings are cylindrical in configuration and made of layers of graphite-epoxy material having fibers oriented in desired stacking sequences. The shells and pinch rings are concentrically assembled in a desired sequence with some of the shells being adapted to perform a structural load bearing function while others of the shells are adapted to perform a load transfer function and with the pinch rings adapted to perform additional stiffening as well as load redistributing and transfer functions in the regions of the joint bonds between the assembled shells and the external structure.

Abstract: A uniform stiffness laminated composite shell assembly includes a plurality of composite shells. The shells are made of layers of laminates of graphite-epoxy material having fibers oriented in various stacking sequences for performing different functions in the assembly. The shells are concentrically assembled in a desired sequence with some of the adjacent ones of the shells being at least equal to or greater in axial length than others thereof and with some of the shells being adapted to perform a structural load bearing function while others of the shells being adapted to perform a load transfer function. The desired sequence of shells of the composite shell assembly provides enhanced thermal insulating properties and efficient load distributing properties for enabling use of the assembly as a tube suspension in a superconductive magnet.

Abstract: A magnet having an imaging volume, a pole piece with a laminated portion including a first surface hole, a non-magnetizable first insert with an internally-threaded hole, and a first shim with a shape of an externally-threaded bolt. The first insert is positioned in the first surface hole and is attached to the pole piece. The first shim is threaded into the hole of the first insert. Additional shims for additional inserts for additional surface holes are used to shim the magnet to reduce magnetic field inhomogeneities in the imaging volume.

Abstract: A magnet, such as an open or closed magnet, has a first assembly with at least one superconductive main coil and with a first vacuum enclosure enclosing the main coil(s). A first cryocooler coldhead has a rigid first housing and is generally vertically aligned. A first flexible bellows is vertically aligned, has a first end attached to the first housing of the first cryocooler coldhead and has a second end attached to the first vacuum enclosure of the first assembly.

Abstract: A magnet, such as a closed, superconductive, magnetic-resonance-imaging (MRI) magnet, includes a main coil and includes a shielding coil positioned radially outward from the main coil. A magnetizable member is positioned radially outward from the main coil and radially inward from the shielding coil to supplement the strength, and increase the homogeneity of, the magnetic field created, at least in part, by the main coil and to supplement the shielding provided, at least in part, by the shielding coil.

Abstract: A magnet, such as a closed, superconductive, magnetic-resonance-imaging (MRI) magnet includes a main coil, a correction coil, and a shielding coil positioned radially outward from the main and correction coils. Two magnetizable members are positioned radially outward from the main and correction coils and radially inward from the shielding coil to shorten the magnet, to supplement the strength, and increase the homogeneity of, the magnetic field created, at least in part, by the main and correction coils and to supplement the shielding provided, at least in part, by the shielding coil.

Abstract: A magnet, such as a closed, superconductive, magnetic-resonance-imaging (MRI) magnet includes a main coil, a magnetizable article, and a shielding coil positioned radially outward from the main coil and magnetizable article. Two magnetizable members are positioned radially outward from the main coil and magnetizable article and radially inward from the shielding coil to supplement the strength, and increase the homogeneity of, the magnetic field created, at least in part, by the main coil and magnetizable article and to supplement the shielding provided, at least in part, by the shielding coil.

Abstract: An open magnet has vertically aligned first and second assemblies each with at least one superconductive main coil. At least one support member is vertically aligned and attached to, the first and second assemblies. At least one cryocooler coldhead is aligned generally horizontally and has a housing which is attached to, and receives weight-bearing support from, one of the first and second assemblies.

Abstract: A vertically-aligned open magnet includes first and second (i.e., top and bottom) assemblies each having a longitudinally-extending and vertically-aligned axis, a superconductive main coil, and a vacuum enclosure enclosing the main coil. At least one support beam has a first end attached to the first assembly and has a second end attached to the second assembly. An annularly-cylindrical support skirt is coaxially aligned with the axes, has a first longitudinal end attached to the second assembly and has a second longitudinal end supportable by a floor.

Abstract: A magnet, such as an open or closed magnet, has a first assembly with at least one superconductive main coil and with a first vacuum enclosure enclosing the main coil(s). A first cryocooler coldhead has a rigid first housing and is generally vertically aligned. A first flexible bellows is vertically aligned, has a first end attached to the first housing of the first cryocooler coldhead and has a second end attached to the first vacuum enclosure of the first assembly.

Abstract: A magnet, such as an open magnetic-resonance-imaging (MRI) magnet) has a first assembly including a superconductive main coil and a magnetizable pole piece which, during magnet operation, has a temperature equal to generally the temperature of the main coil. In one example, a cryogenic-fluid (e.g., liquid helium) dewar encloses the main coil, and the dewar has an interior surface defined in part by a surface portion of the pole piece. A method for providing a homogeneous imaging volume for a magnet includes steps to construct the above-described magnet.

Abstract: A magnet pole piece assembly has first and second pole pieces and at least one support member. The pole pieces have longitudinally aligned and facing surface recesses. The support member has a central segment and first and second end segments abuttingly and metallurgically attached to the central segment. The first and second end segments are positioned within a corresponding surface recess of the first and second pole piece and are abuttingly and metallurgically attached to the corresponding pole piece. An open magnet adds main coils to the magnet pole piece assembly.

Abstract: An open magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced-apart assemblies. Each assembly has a shielding coil located longitudinally outward from a main coil, a magnetizable member not carrying an electric current and spaced apart from and proximate the main and shielding coils, and a magnetizable pole piece spaced apart from the magnetizable member: The method of the invention generates a magnetic field in a first area between the two assemblies while shielding a second area not between the two assemblies from a stray magnetic field by creating the previously-described open magnet.

Abstract: An open magnetic resonance imaging (MRI) magnet having first and second spaced-apart superconductive coil assemblies each including a toroidal-shaped coil housing containing a superconductive main coil at least partially immersed in a cryogenic fluid such as liquid helium. A generally-non-permanently-magnetized ferromagnetic ring is associated with each coil assembly, being generally coaxially aligned with the associated coil assembly and being spaced radially inward and radially apart from the associated coil assembly's superconductive main coil. The ferromagnetic rings overcome the gross magnetic field distortions in the imaging volume of the superconductive main coils (created by the open space between the magnet's superconductive coil assemblies) to produce a magnetic field of high uniformity within the imaging volume.

Abstract: A superconductive magnet includes a cryogenic vessel enclosing superconductive coils, a thermal shield enclosing the cryogenic vessel, a vacuum enclosure enclosing the thermal shield, a tube suspension assembly having a plurality of tubes located between respective ones of the cryogenic vessel, thermal shield and vacuum enclosure and axially overlapped and interconnected with the cryogenic vessel, thermal shield and vacuum enclosure and the tubes forming bonded joints with one another, and a plurality of locking clip arrangements attached to and having portions at least partially overlapping the bonded joints of the tubes of the suspension assembly so as to reinforce and strengthen the bonded joints.

Abstract: A superconductive magnet includes a superconductive coil assembly having a cryogenic vessel, a thermal shield enclosing the cryogenic vessel, and a vacuum enclosure enclosing the thermal shield. The cryogenic vessel, thermal shield and vacuum vessel have annular shells radially spaced apart from one another with reference to a common longitudinal axis and coaxially aligned with the common longitudinal axis. The magnet also includes a tube suspension assembly having a plurality of tubes located between respective ones of the cryogenic vessel, thermal shield and vacuum enclosure. The tubes are axially overlapped and are interconnected with one another and with the cryogenic vessel, thermal shield and vacuum enclosure. One tube has an end forming a sliding joint with the cryogenic vessel that allows both radial and axial movement of the cryogenic vessel relative to the thermal shield and vacuum enclosure during cooldown of the cryogenic vessel from ambient to cryogenic temperatures.

Abstract: An open magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced-apart assemblies. Each assembly has a shielding coil located longitudinally outward from a main coil and a magnetizable pole piece spaced apart from and proximate the main and shielding coils. The method of the invention generates a magnetic field in a first area between the two assemblies while shielding a second area not between the two assemblies from a stray magnetic field by creating the previously-described open magnet.

Abstract: An open magnet useful in magnetic resonance imaging (MRI) applications. The magnet has two spaced-apart assemblies. Each assembly has a shielding coil located longitudinally outward from a main coil, a magnetizable member not carrying an electric current and spaced apart from and proximate the main and shielding coils, and a magnetizable pole piece spaced apart from the magnetizable member: The method of the invention generates a magnetic field in a first area between the two assemblies while shielding a second area not between the two assemblies from a stray magnetic field by creating the previously-described open magnet.