Patent application number | Description | Published |
20090033450 | LOW EDDY CURRENT CRYOGEN CIRCUIT FOR SUPERCONDUCTING MAGNETS - A low eddy current cryogen circuit for superconducting magnets including at least a first cooling coil made of an electrically conducting material and having at least one electrical isolator incorporated in the first cooling coil. The electrical isolator is located to inhibit induced eddy current loops due to inductive coupling of the first cooling coil with eddy current inducing field sources. | 02-05-2009 |
20100001596 | System and method for cooling a superconducting rotary machine - A system for cooling a superconducting rotary machine includes a plurality of sealed siphon tubes disposed in balanced locations around a rotor adjacent to a superconducting coil. Each of the sealed siphon tubes includes a tubular body and a heat transfer medium disposed in the tubular body that undergoes a phase change during operation of the machine to extract heat from the superconducting coil. A siphon heat exchanger is thermally coupled to the siphon tubes for extracting heat from the siphon tubes during operation of the machine. | 01-07-2010 |
20100013584 | METHOD AND APPARATUS FOR ACTIVELY CONTROLLING QUENCH PROTECTION OF A SUPERCONDUCTING MAGNET - A method and apparatus for actively controlling quench protection of a superconducting magnet includes a magnetic resonance imaging (MRI) system and a computer readable storage medium having stored thereon a computer program comprising instructions which when executed by a computer cause the computer to detect a quench condition of the superconducting magnet. The instructions also cause the computer to actively control a quench protection system of the superconducting magnet in response to the detected quench condition. | 01-21-2010 |
20100237868 | APPARATUS FOR LOW AC LOSS THERMAL SHIELDING AND METHOD OF MAKING SAME - A apparatus for low AC loss thermal shielding includes a plurality of thermally conducting fibers positioned along a desired direction of heat conduction. The fibers are electrically insulated from each other. The fibers are bonded together with a matrix, and a thermal link connects the bonded fibers to a cryogenic cold head. | 09-23-2010 |
20100242500 | THERMAL SWITCH FOR SUPERCONDUCTING MAGNET COOLING SYSTEM - The present invention provides an apparatus and method for automatically disconnecting a cryocooler from a cold mass reservoir of a MR system. A cryocooler thermal link includes a first end plate configured to be thermally connected to a cryocooler and a second end plate configured to be thermally connected to a cold mass. A wall encloses a space between the first and the second end plates, the wall having a first end attached to the first end plate and a second end attached to the second end plate. A working fluid is positioned in the space. | 09-30-2010 |
20100277170 | HEAT PIPE COOLED SUERCONDUCTING MAGNETS WITH CERAMIC COIL FORMS - A system and method for a magnetic resonance (MR) imaging system includes a coil form, at least one magnet positioned about the coil form and configured to generate a magnetic field, at least one gradient coil for manipulating the magnetic field generated by the at least one magnet by way of a gradient field, and a heat pipe thermally connected to the coil form and having a cryogen therein. The MR imaging system also includes a cryocooler connected to the heat pipe to cool the heat pipe and the cryogen, wherein the coil form is comprised of a thermally conductive material in which eddy currents are substantially reduced during operation of the at least one gradient coil. The present invention has been described in terms of the preferred embodiment, and it is recognized that equivalents, alternatives, and modifications, aside from those expressly stated, are possible and within the scope of the appending claims. | 11-04-2010 |
20110069418 | PASSIVE QUENCH PROTECTION CIRCUIT FOR SUPERCONDUCTING MAGNETS - 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. | 03-24-2011 |
20110101982 | CRYOGENIC SYSTEM AND METHOD FOR SUPERCONDUCTING MAGNETS - 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. | 05-05-2011 |
20110179809 | COOLING SYSTEM AND METHOD FOR SUPERCONDUCTING MAGNETS - A method for cooling a superconducting magnet enclosed in a cryostat of a magnetic resonance imaging system comprises introducing a gas into a cooling path in the cryostat from an input portion outside the cryostat. A heat exchanger in the cooling path is cooled by a refrigerator outside the cryostat. The gas at the heat exchanger is cooled as a cold gas or is condensed at the heat exchanger into a liquid cryogen. The cold gas or liquid cryogen from the heat exchanger flows through at least a connection tube to a magnet cooling tube, which is in thermal contact with the superconducting magnet. Heat from the superconducting magnet is removed by warming the cold gas into warm gas or by the boiling the liquid cryogen into boiled-off gas. The warm gas or boiled-off gas is transmitted back to the heat exchanger to re-cool the warm gas or re-condense the boiled-off gas for further cooling the superconducting magnet to a superconducting temperature. The input portion is closed to make the cooling path as a closed-loop for maintaining the superconducting magnet below the superconducting temperature. | 07-28-2011 |
20110193665 | SUPERCONDUCTING MAGNETS WITH AN IMPROVED SUPPORT STRUCTURE - 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. | 08-11-2011 |
20120004109 | MAGNET ASSEMBLIES AND METHODS FOR TEMPERATURE CONTROL OF THE MAGNET ASSEMBLIES - 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. | 01-05-2012 |
20120007703 | CURRENT LEAD ASSEMBLY FOR SUPERCONDUCTING MAGNET - 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. | 01-12-2012 |
20120068795 | MAGNET ASSEMBLIES AND METHODS FOR MAKING THE SAME - 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. | 03-22-2012 |
20120071326 | QUENCH PROTECTION CIRCUIT FOR SUPERCONDUCTING MAGNET COILS - 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. | 03-22-2012 |
20120135868 | SUPERCONDUCTING MAGNET ASSEMBLY AND FABRICATING METHOD - 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. | 05-31-2012 |
20120165200 | METHODS FOR MAKING LOW RESISTIVITY JOINTS - 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. | 06-28-2012 |