Abstract: A gradient coil assembly (62) for use in a Magnetic Resonance Imaging (MRI) system includes primary coils (68), shield coils (72) and a supporting structure (10) arranged between the primary coils (68) and the shield coils (72). The supporting structure (10) includes at least a supporting element (12) including a first end face (14) and at least a first recess (24) with an opening (26) in the first end face (14). The first recess (24) extends in a longitudinal direction (18) of the supporting element (12) forming a tray for receiving a passive shim bar.

Abstract: The invention concerns to a gradient coil assembly (62) for use in a Magnetic Resonance Imaging (MRI) system. The gradient coil assembly (62) comprises primary coils (68), shield coils (72) and a supporting structure (10) being arranged between the primary coils (68) and the shield coils (72), wherein the supporting structure (10) comprises at least a supporting element (12) comprising a first end face (14) and at least a first recess (24) with an opening (26) in the first end face (14), wherein the first recess (24) extends in a longitudinal direction (18) of the supporting element (12) forming a tray for receiving a passive shim bar.

Abstract: An apparatus includes at least a first electrically conductive coil having at least first and second coil sections which are separated and spaced apart from each other, and a support structure disposed to support the first and second coil sections. The support structure, and an associated method of supporting the electrically conductive coil, maintain relative axial positions of the first and second coil sections to be fixed when the first electrically conductive coil is energized and de-energized, and allow each of the first and second coil sections to expand radially when energized.

Abstract: An apparatus includes an electrically conductive coil which produces a magnetic field when an electrical current passes therethrough; a selectively activated persistent current switch connected across the electrically conductive coil; a cryostat having the electrically conductive coil and the persistent current switch disposed therein; an energy dump; at least one sensor which detects an operating parameter of the apparatus and outputs at least one sensor signal in response thereto; and a magnet controller. The magnet controller receives the sensor signal(s) and in response thereto detects whether an operating fault (e.g. a power loss to the compressor of a cryocooler) exists in the apparatus, and when an operating fault is detected, connects the energy dump unit across the electrically conductive coil to transfer energy from the electrically conductive coil to the energy dump unit. The energy dump unit disperses the energy outside of the cryostat.

Abstract: An apparatus includes at least a first electrically conductive coil having at least first and second coil sections which are separated and spaced apart from each other, and a support structure disposed to support the first and second coil sections. The support structure, and an associated method of supporting the electrically conductive coil, maintain relative axial positions of the first and second coil sections to be fixed when the first electrically conductive coil is energized and de-energized, and allow each of the first and second coil sections to expand radially when energized.

Abstract: Method for joining wires using low resistivity joints is provided. More specifically, methods of joining one or more wires having superconductive filaments, such as magnesium diboride filaments, are provided. The wires are joined by a low resistivity joint to form wires of a desired length for applications, such in medical imaging applications.

Abstract: A superconducting magnet assembly includes a bobbin comprising a central bore along a longitudinal direction, and a superconducting coil package wound on the bobbin. The superconducting coil package includes a plurality of superconducting coil layers wound on the bobbin, a plurality of supporting member layers, each of the supporting member layers being between a corresponding two adjacent superconducting coil layers, and a thermal conduction layer between two superconducting coil layers or between a superconducting coil layer and an adjacent supporting member layer.

Abstract: A superconducting magnet apparatus that in one embodiment includes at least one superconducting coil and a passive quench protection circuit electrically coupled to the coil in parallel. The circuit includes a heater and a current limiter connected in series. The heater is thermally coupled to the coil and the current limiter blocks current through the circuit at a current lower than the current rating of the heater.

Abstract: A superconducting magnet is described and includes at least one superconducting coil, at least one support member coupled to the superconducting coil and at least one compliant interface between the superconducting coil and the support member. The superconducting coil defines a radial direction. The superconducting coil supports the superconducting coil along an axial direction that is substantially perpendicular to the radial direction. The compliant interface is configured to move along the radial direction when the superconducting magnet is energized.

Abstract: A cryogenic system for a superconducting magnet comprises a closed-loop cooling path. The closed-loop cooling path comprises a magnet cooling tube thermally coupled to the superconducting magnet. The magnet cooling tube comprises a cryogen flow passage. The closed-loop cooling tube further comprises a re-condenser is fluidly coupled to the magnet cooling tube through tube sections and a liquid cryogen container fluidly coupled between the magnet cooling tube and the re-condenser. At least one gas tank is fluidly coupled to the magnet cooling tube through a connection tube.

Abstract: A magnet assembly is provided. The magnet assembly comprises a magnet configured to generate a magnetic field and an iron shield configured to shield the magnet. The magnet assembly further comprises one or more positive temperature coefficient heaters disposed on the iron shield and configured to stabilize temperature of the iron shield. An iron shield assembly and a method for temperature control of the magnet assembly are also presented.

Abstract: A superconducting magnet includes at least one superconducting coil and a quench protection circuit electrically coupled to said at least one coil in parallel. The circuit includes at least one quench heater assembly thermally coupled to the at least one coil, and at least one superconducting current limiter electrically connected in series with the at least one quench heater assembly. The superconducting current limiter has a superconducting state with zero resistance, and a normal state with a normal resistance to decrease an electric current flowing through the quench heater assembly.

Abstract: A method for cooling a superconducting magnet enclosed in a cryostat includes introducing a gas into a cooling path in the cryostat from an input portion into a cooling path cooled by a refrigerator outside the cryostat. A heat exchanger inside the cryostat above the magnet cools the gas. The cooled gas flows through a magnet cooling tube contacting the magnet. The cooled gas removes heat from the magnet, and to the heat exchanger to re-cool and return to the superconducting magnet, thereby cooling and/or maintaining the magnet at a superconducting temperature.

Abstract: A superconducting magnet assembly is provided. The superconducting magnet assembly includes a superconducting magnet configured to generate a static magnetic field, an iron shield configured to shield the superconducting magnet, and a magnetic gradient coil assembly configured to generate a gradient magnetic field. The superconducting magnet assembly further includes one or more magnetic lamination elements disposed on the iron shield to reduce eddy current induced by the gradient magnetic field in the iron shield. A method is also presented.

Abstract: Method for joining wires using low resistivity joints is provided. More specifically, methods of joining one or more wires having superconductive filaments, such as magnesium diboride filaments, are provided. The wires are joined by a low resistivity joint to form wires of a desired length for applications, such in medical imaging applications.

Abstract: A superconducting magnet assembly includes a bobbin comprising a central bore along a longitudinal direction, and a superconducting coil package wound on the bobbin. The superconducting coil package includes a plurality of superconducting coil layers wound on the bobbin, a plurality of supporting member layers, each of the supporting member layers being between a corresponding two adjacent superconducting coil layers, and a thermal conduction layer between two superconducting coil layers or between a superconducting coil layer and an adjacent supporting member layer.

Abstract: A superconducting magnet assembly is provided. The superconducting magnet assembly includes a superconducting magnet configured to generate a static magnetic field, an iron shield configured to shield the superconducting magnet, and a magnetic gradient coil assembly configured to generate a gradient magnetic field. The superconducting magnet assembly further includes one or more magnetic lamination elements disposed on the iron shield to reduce eddy current induced by the gradient magnetic field in the iron shield. A method is also presented.

Abstract: A superconducting magnet includes at least one superconducting coil and a quench protection circuit electrically coupled to said at least one coil in parallel. The circuit includes at least one quench heater assembly thermally coupled to the at least one coil, and at least one superconducting current limiter electrically connected in series with the at least one quench heater assembly. The superconducting current limiter has a superconducting state with zero resistance, and a normal state with a normal resistance to decrease an electric current flowing through the quench heater assembly.

Abstract: A current lead assembly includes a current lead having an end, at least one heat station thermally coupled to the end, a cryogen-flow path extending through the heat station and comprising at least one connection, and a cryogen generation source fluidly coupled to the cryogen-flow path through the connection.

Abstract: A magnet assembly is provided. The magnet assembly comprises a magnet configured to generate a magnetic field and an iron shield configured to shield the magnet. The magnet assembly further comprises one or more positive temperature coefficient heaters disposed on the iron shield and configured to stabilize temperature of the iron shield. An iron shield assembly and a method for temperature control of the magnet assembly are also presented.