Abstract: A seat, a chair, or a combination thereof can be part of or used in conjunction with an MRI system. The seat can be designed to allow for an MRI analysis without requiring insertion of a probe into a cavity of a patient. In one embodiment, the seat and chair can be adapted for use with a cylindrical-type MRI system. The seat and chair may be used with another type of MRI system, such as an open MRI system. The pelvic region or adjacent portion of a patient can be analyzed without the patient having to lie flat.

Abstract: A cylindrical MRI system can be configured such that a patient does not have to be in a lying position during analysis. In a particular embodiment, the patient can sit during analysis. The cylindrical MRI system can be oriented such that a central axis is not parallel to the floor, and in one embodiment, is substantially perpendicular to the floor. In one embodiment, the cylindrical MRI system can be configured to allow an object to contact the patient when the patient is within the analyzing region, even when the primary magnet is at field. In another aspect, an MRI system can include a primary magnet and a gradient coil with different types of shapes. In still another aspect, an MRI system can include a gradient coil that includes a combination of portions having different shapes.

Abstract: A switch can be used in conjunction with a superconducting current path to provide a more reliable circuit and system. The switch can be connected in parallel with a portion of the superconducting current path. In one embodiment, the switch may be connected in parallel with an entire superconducting element, such as a persistent current switch, a superconducting coil, or the like, or may be connected in parallel across only a portion of a superconducting element. A method of using the system is also disclosed.

Abstract: A housing can include a first member and a second member, wherein the first and second members can be rotated with respect to each other and joined at an acute angle. A system can include a valve assembly and a housing. The valve assembly can include an interface. The housing can include a first member and a second member. The valve assembly can be attached to the first member, and the interface of the valve assembly can be directly visible from the first opening of the second member. A method of using a system can allow a ruptureable member to be accessed without requiring a valve assembly to be removed, allow a more direct path between a fluid flow passed surfaces of an interface and an exhaust connection, or any combination thereof.

Abstract: A valve assembly can include a ruptureable member. The ruptureable member may be secured in place by a first support member, a second support member, and one or more removable engaging elements. The valve assembly can be configured such that the ruptureable member can be removed when a single removable engaging element is removed. In another embodiment, a valve assembly can include a plunger having a substantially solid shaft. The valve assembly can also include a ruptureable section attached to the substantially solid shaft. In still another embodiment, a valve assembly can include a plunger including a stem portion and a motion limiter portion, wherein the motion limiter portion is wider than the stem portion. The valve assembly can also include a spring surrounding the stem portion and the motion limiter portion, wherein the motion limiter portion is configured to keep the spring from becoming fully compressed.

Abstract: A method can be used to perform an operation on a system that includes an assembly and a vessel that includes a wall and a thermal shield. The method can include breaking a thermal connection between the assembly and the thermal shield, separating the assembly and a surface within the vessel from each other, or any combination thereof. The method can also include changing a pressure with the vessel to be closer to atmospheric pressure, heating the assembly, or any combination thereof. In one embodiment, the method can be performed while keeping a cryogenic region substantially sealed, keeping a superconducting magnet energized, or a combination thereof. In a particular embodiment, the method can be used when servicing the assembly, such as a cryocooler.

Abstract: An open or split type MRI apparatus has two axially spaced magnet coil half sections separated and supported by a compact support structure. Only two diametrically opposed supports are needed to react the high axial and torsional loads produced or received by the MRI apparatus. One support is loaded under pure compression, and the other support is loaded under compression and tension.

Abstract: A cylindrical magnet assembly for use in magnetic resonance imaging apparatus has a radially compact construction which eliminates prior manufacturing steps. Recesses are formed in insulation layers for receiving complimentary shaped bus bars. Because the bus bars are dimensioned to fit flush within the recesses, they do not add to the radial growth of the magnet assembly.

Abstract: Refrigerants containing R-22 are replaced with new blends by using R-125, or R-125 with R-124, or R-218, or R-218 with R-124, in place of R-22. No hardware or oil composition changes are required to maintain temperatures, pressures and capacity substantially unchanged in a refrigeration system.

Abstract: A gradient coil assembly is directly coupled throughout its entire axial length and circumferential area to the inner cylinder of the cryostat vacuum container enclosing a cylindrical superconducting MRI static field magnet. Any air space between the concentric gradient coil assembly and the cryostat is eliminated. This stiffer system produces lower velocities of the switched gradient coil assembly, which in turn produces lower noise levels in the patient opening of the gradient coil assembly and in the ambient environment. Alternatively, an annular space separates the gradient coil assembly from the MRI static field magnet assembly, and the gradient coil assembly is rigidly coupled to the inner cylinder of the MRI static field magnet assembly by discrete coupling rings. The annular space or chamber between the two assemblies is broken into smaller volumes or subchambers, which do not interconnect in the axial direction and thereby prevent axial propagation of noise generated in the chambers.

Abstract: A cylindrical magnet assembly for use in magnetic resonance imaging apparatus has a radially compact construction which eliminates prior manufacturing steps. Recesses are formed in insulation layers for receiving complimentary shaped bus bars. Because the bus bars are dimensioned to fit flush within the recesses, they do not add to the radial growth of the magnet assembly.

Abstract: Increasing RF transmission power, retuning the RF transmitter and receiver coils, and increasing RF reception gain, enable MR inspection of product in a container that presents a substantial portion of an electrically conductive barrier in transverse orientation to the exciting RF magnetic field.

Abstract: A GM type displacer has an elastomer “O” ring at the warm end to absorb impact energy when the displacer reaches the bottom of the stroke before it would hit the cylinder end cap. When the displacer reaches the top of its stroke, before the displacer would hit the internal mechanism of the expander, another elastomer “O” ring absorbs the kinetic energy of the displacer. Both absorbers are at or near ambient temperature.

Abstract: In a high field superconducting magnet device, e.g., for NMR, a conventional low temperature superconducting solenoid type magnet is combined with an inserted superconducting magnet, which is fabricated from high temperature superconducting materials having very high critical currents. Both magnets operate with stability at the same low temperature in persistent modes after operating conditions are achieved. The flux field and superconducting currents in the inserted superconducting magnet are generated by flux trapping when the field of the low temperature superconducting solenoid type magnet is reduced. The field of the hybrid magnet assembly is the resultant of the respective fields of the two magnets.

Abstract: A superconducting magnet is accessible for ramping within a cryostat by inserting flexible current leads through openings in the cryostat and pushing and twisting these leads inward until connections are made with electrical contacts provided on the superconducting magnet. For each current lead, a permanently installed channel guides the lead as it is pushed through the external opening and extends to make contact with the magnet terminal. The guide channel extends outside of the cryostat and includes an internal or external bend, whereby the overhead space required for the cryostat/magnet assembly may be reduced. After ramping, the leads are withdrawn.

Abstract: A magnetic array for periodic magnetic devices is formed as a series of pole modules each constructed from rectangular components. Field strengths in excess of 2.0 T are achieved by surrounding each pole module on all available sides with magnet blocks. Less magnet material is used than in prior modules that produced equal field strengths and magnet material is more efficiently used by reducing the material scrap associated with manufacture of prior art pole and magnet designs.

Abstract: In a high field superconducting magnet device, e.g., for NMR, a conventional low temperature superconducting solenoid type magnet is combined with an inserted superconducting magnet, which is fabricated from high temperature superconducting materials having very high critical currents. Both magnets operate with stability at the same low temperature in persistent modes after operating conditions are achieved. The flux field and superconducting currents in the inserted superconducting magnet are generated by flux trapping when the field of the low temperature superconducting solenoid type magnet is reduced. The field of the hybrid magnet assembly is the resultant of the respective fields of the two magnets.

Abstract: In a magnetic resonance imaging system, wherein a subject to be imaged is supported within a bore of a magnet assembly and exposed to radio frequency (RF) energy emitted from an excitation coil, gradient coils and an RF screen are disposed within the region of the bore exteriorly to an excitation coil and are configured with a split or open region facing sections of the excitation coil for reduced image currents in the gradient coils and the RF screen from RF field generated by the excitation coil. The X gradient coil is reduced to two enlarged coil sections to the left and to the right of the bore. The two opposed sections of the X gradient coil, the two opposed sections of the Y gradient coil, and the opposed pairs of sections of the Z gradient coil are spaced apart at the top and the bottom of the bore for reduced interaction with the excitation coil section located at the top and the bottom of the bore. Thereby, the space between the excitation coil and the shield can be reduced.

Abstract: A permanent magnet assembly having a central elliptical bore, suitable for reception of a patient in an MRI system, is formed of a plurality of elliptically shaped sections disposed along an axis of the bore. Each section is subdivided into a plurality of segments in which each segment is constructed of bricks of magnetic material. Each brick has the shape of a right parallel piped. In any one of the segments, all of the bricks are arranged parallel to a common plane which is parallel to the bore axis. The bricks are magnetized with magnetization vector oriented in a common direction perpendicular to the plane. Full bricks are employed throughout all of the segments with the exception of a plurality of bricks along a surface of the bore wherein truncation of one or more of the bricks may be required to attain a desired homogeneity to a dipole magnetic field within the field.

Abstract: A superconducting magnetic energy storage system for applying power to a load includes a superconducting magnet, the inductor of which is supplied with current via a source which may be preset to a desired value of current, and wherein a feedback loop responsive to a sensed current adjusts the source to provide the desired current. Energy from the superconducting magnet is transferred via a series of pulses of current from the magnet to a first capacitor for charging the capacitor to a desired voltage greater than the voltage at the superconducting magnet. A further transfer of energy, via a series of pulses of current, results in a charging of a second capacitor to a voltage lower than the voltage of the first capacitor. The second capacitor feeds the load.