Abstract: In a superconducting magnet assembly a plurality of superconducting coils, joined in series, are housed within a cryostat. A coil node between two electrically adjacent of the superconducting coils provides an input voltage. A coil node voltage output is provided comprising a series resistor connected between the coil node and a further node. A non-linear element is connected between the further node and a ground voltage, and an output connector is electrically connected to the further node and traverses a boundary of the cryostat.

Abstract: A method of forming an encapsulated coupled coil arrangement. The method includes coupling a first lead of a first coil to a second lead of an electrical circuit device, by soldering or infusion, using a superconductive jointing alloy; and encapsulating the first coil, the electrical circuit device and the jointed leads of the first coil and the electrical circuit device in an encapsulation material. The jointing alloy has a melting point higher than a highest temperature experienced by the encapsulation material during the encapsulation process.

Abstract: In a solenoidal electromagnet arrangement for a magnetic resonance imaging system, annular inner coils and annular end coils are provided, all concentrically aligned about an axis, the end coils being placed at axial extremities, axially outside of the inner coils. A pair of annular outer coils are provided concentrically aligned about the axis. An arrangement is provided retaining the pair of outer coils against an axial force urging the outer coils away from one another. The arrangement comprises strap elements which extend around a radially inner surface, a radially outer surface and an axially outer surface of each outer coil in certain circumferential locations. Each strap element on one of the outer coils is linked to a corresponding strap element on the other outer coil of the pair by a tensile member.

Abstract: A current lead-through for providing an electrically conductive path between an interior of a vessel and the exterior of the vessel. The electrically conductive path is electrically isolated from the material of the vessel. The current lead-through comprises an electrically conductive pin surrounded by an electrically isolating sealing material, and retained within a tubular carrier body by the sealing material, the electrically conductive pin being exposed at each end of the tubular carrier body to enable electrical connection thereto.

Abstract: A protection apparatus for a superconductive magnet unit has a support frame for location relative to a portion of the superconductive magnet unit. The support frame is arranged to carry a buffer for protecting the superconductive magnet unit from a shock load.

Abstract: A coil energizing apparatus has a superconducting energization power supply having an output port. The power supply is arranged to generate, when in use, a pulsed output current signal at the output port.

Abstract: The present invention provides a material for the construction of external coverings accessible by humans or animals. It aims to increase the breakdown voltage between a high voltage VRF, high frequency source of energy and the human or animal, by adaptation of materials and structures. According to an embodiment of the invention, a structure is provided for the cover 18 used in MRI or NMR systems, which carries a greater proportion Vs of the voltage VRF across itself, thereby reducing the voltage Vg across the gap 22 and reducing the likelihood of breakdown.

Abstract: A cryostat comprises a cryogen vessel suspended within an outer vacuum container, the cryogen vessel is supported by an arrangement that includes at least one housing mounted on an exterior surface of the outer vacuum container and arranged to function as a floor mounting foot, for supporting weight of the cryogen vessel and the outer vacuum container, and at least two mounting points mounted within the housing(s). Each of at least two suspension elements (an upper suspension element and a lower suspension element) extends through a hole in the surface of the outer vacuum container, between the respective mounting point and a respective point on the cryogen vessel.

Abstract: A method of manufacturing a solenoidal magnet structure, includes the step of providing a collapsible accurate mold in which to wind the coils winding wire into defined positions in the mold, placing a mechanical support structure over the coils so wound, impregnating the coils and the mechanical support structure with a thermosetting resin, allowing the thermosetting resin to harden, and collapsing the mold and removing the resultant solenoidal magnet structure formed by the resin impregnated coils and the mechanical support structure from the mold as a single solid piece.

Abstract: An imaging magnet has a patient bore for receiving a human or animal patient, including a body coil assembly having a body coil former and a body coil. The body coil assembly is provided with at least one source of light that is incorporated within the body coil assembly, and embedded within the body coil former, that radiates light into the patient bore.

Abstract: A burst disc arrangement for a cryostat comprising a replaceable burst disc (52) held in compression between a high-pressure flange formed at an end of a high-pressure conduit (12), and a low-pressure flange (60) formed at an end of a low-pressure conduit (14). In particular, the burst disc arrangement further comprises: a housing (50) enclosing the high- and low-pressure flanges; and compression means (56), distributed around the housing (50) and being arranged to bear upon the one of the flanges (60), so as to urge it towards the other flange, thereby retaining the burst disc (52) in compression between the flanges. The housing (50) includes a first opening (20) large enough to allow the replaceable burst disc (52) to pass therethrough.

Abstract: A method of measuring a level of liquid cryogen, comprising the steps of immersing a liquid cryogen level probe in a liquid cryogen, applying a propagation current to the heater (26) to induce quench in at least an adjacent part of the superconductive material (22); removing the propagation current from the heater; applying a measurement current to the superconductive material; and measuring (30) a voltage across the superconductive material thereby to determine the level of the liquid cryogen. In articular, the method comprises the steps of monitoring (40) the voltage across the superconductive material while the propagation current is being applied; and ceasing application of the propagation current in response to the detection of a voltage across the superconductive material which exceeds a certain threshold level.

Abstract: Particle radiation therapy equipment arranged to apply a charged particle beam in a predetermined direction to a region of application within an imaging volume, comprising a charged particle beam source arranged to direct a charged particle beam in the predetermined direction, further comprising magnetic field generation means for generating a magnetic field in the region of application at the same time that the charged particle beam is applied, wherein the magnetic field generation means is arranged to provide access to the region of application for the charged particle beam, and to provide a homogeneous magnetic field in the region of application of the charged particle beam, said magnetic field being directed substantially in the predetermined direction.

Abstract: An energy dissipation arrangement for a cryogenically cooled superconductive magnet comprising a plurality of superconductive coils (10) connected in series and housed within a cryostat (24), comprising a superconducting switch (25) having a superconductive current path (28) in series with the superconductive coils (10); and a resistor (38), external to the cryostat, electrically connected in parallel with the superconductive current path (28) of the superconducting switch (25).

Abstract: A cryogen level probe, comprising a superconducting conductor (30); a heater (32) arranged to heat a part of the superconducting conductor; current leads (34, 36) arranged to supply electric current through the superconducting conductor; and voltage sense leads (38; 40) for providing a voltage sensor (44) with a voltage appearing across the superconducting conductor due to the passage of the electric current. The heater, the current leads and the voltage sense leads are formed as foil tracks on a flexible substrate (50). The superconducting conductor may also be formed as a foil track on the flexible substrate.

Abstract: A quench line and exit plenum configuration for a mobile MRI system housed in a transportable trailer includes an exit plenum with deflector plates that direct the quench flow of cold gases upward and away from surrounding objects. In addition, the plenum also includes dual vents to facilitate optimum gas flow and water drainage. The deflector plates are configured to utilize the Venturi effect to create an auxiliary flow of the ambient air to help deflect the flow of cold gases away from nearby pedestrians, when the magnet is quenching, and to enable service personnel to fill the magnet safely while in the vicinity of the exit plenum.

Abstract: A pre-assembled, pre-tested quench path outlet assembly for providing a cryogen egress path from a cryogen vessel. A quench valve (26) is mounted within a flange (28). A cryogen egress tube (32) is sealed in leak-tight manner to the flange, to define a cryogen egress path (40) extending through the cryogen egress tube, the flange and the quench valve. The cryogen egress path is closed by a burst disc (34). In use, the pre-assembled, pre-tested quench path outlet assembly is mounted onto the cryogen vessel such that thermal stratification of gas within the cryogen vessel under normal conditions causes a lower end of the cryogen egress tube to be at a temperature below the freezing points of common air components.

Abstract: A method for manufacturing a solenoidal magnet having one or more coils wound onto a cylindrical former, and an annular end coil (20), mounted onto an end of the former such that no part of the former is present on the radially inner (A1) or axially outer (B2) sides of the end coil.

Abstract: A method of manufacturing a solenoidal magnet structure, comprising the steps of providing a collapsible mold in which to wind coils; winding wire into defined positions (88) in the mold to form coils (34); placing a preformed tubular mechanical support structure (102, 120) over the coils (34) so wound; impregnating the coils and bonding them to the mechanical support structure by applying a thermosetting resin and allowing the thermosetting resin to harden; and collapsing the mold and removing the resultant solenoidal magnet structure comprising the resin impregnated coils and the mechanical support structure from the mold as a single solid piece.

Abstract: A switching circuit including a plurality of heating elements (12), each connected as part of a tuned circuit (36), the tuned circuits being respectively tuned to different frequencies and connected in parallel between two common conductors (34), the circuit further including a device (20, 38, 40) for applying an oscillating signal voltage between the two common conductors, at one or more frequencies each corresponding to a tuned frequency of one of the tuned circuits.