Hitachi, Ltd.

Akihisa Miyazoe

Manabu Aoki

Takeshi Nakayama

Masahiro Kawasaki

Mitsushi Abe

Ryuya Ando

Yukinobu Imamura

Tadashi Arai

Kenji Okishiro

Chishin Hori

Yukihiro Murata

A deflection electromagnet device generates a high magnetic field without increasing the size of a vacuum duct to facilitate control over a beam orbit. Magnetic flux lines from a return pole pass through the vacuum duct of a high-temperature superconductor in a vacuum heat insulation container and the charged particle beam is thus deflected, thereby generating radiation. A three-pole magnetic field is formed on the beam orbit and the charged particle beam is thus deflected by individual magnetic fields, so that radiation can be generated while the charged particle beam returns to a coaxial orbit. Therefore, an increase in size of the vacuum duct can be prevented. A shielding current is dominant and the non-uniformity of the magnetic field in a z-axis direction is prevented by disposing the high-temperature superconductor having a crystal direction c-axis orthogonal to a horizontal plane in which the charged particle beam flows.

Deflection electromagnet device

A superconducting magnet in which efficiency of conduction cooling is improved is described as well as a magnetic resonance imaging apparatus that includes the superconducting magnet and requires no liquid helium. The magnet resonance imaging apparatus includes: a coil portion including a winding core, a winding portion formed by winding a wire around the winding core, a first flange provided on one side of the winding core, and a second flange provided on the other side of the winding core; a cooling device for cooling the coil portion; and a heat conducting member for thermally connecting the coil portion and the cooling device, in which at least one of the first flange, the second flange, and the winding core has a region made of a material whose thermal contraction rate is larger than a thermal contraction rate of the winding portion.

Superconducting magnet and magnetic resonance imaging apparatus

The objective of the present invention is to provide a conduction-cooling-type super-conducting magnet, wherein a surface pressure is applied between a super-conducting coiled wire portion and a cooling member, the non-uniformity of the surface pressure in the diameter direction of the coiled wire portion has been improved, whereby the uniformity of contact heat resistance has been improved, moreover, warping due to a thermal contraction difference between the cooling member and the coiled wire portion arising at cooling time has been decreased sufficiently, and a surface pressure application mechanism can be installed solely in the low-temperature portion where the super-conducting coiled wire portion is installed. Provided is a conduction-cooling-type super-conducting magnet characterized by: an adequate heat conductor, which is connected to a cooler, in contact with the super-conducting coiled wire portion; the inclusion of an elastic body, which is capable of imparting, in the form of a displacement, an amount of contraction that is sufficiently greater than the amount of contraction of the adequate heat conductor and the wound wire portion at cooling time; and at least one elastic body disposed on each of the inner peripheral side and the outer peripheral side of the coiled wire portion in the same radial direction of the coiled wire portion.

Superconducting magnet

An object is to provide a super-conducting coil and a magnetic resonance imaging device that are quench-free by reducing Joule heat generated upon occurrence of separation of members even in a high magnetic field. The super-conducting coil in accordance with the present invention includes a spool and a super-conducting wire wound around the spool. The coil further includes, between the spool and the super-conducting wire, a first resin layer containing thermoplastic resin, a second resin layer containing thermosetting resin, and a mixed layer, the mixed layer being positioned between the first resin layer and the second resin layer and containing a mixture of the thermoplastic resin and the thermosetting resin.

Super-conducting wire, super-conducting coil, and magnetic resonance imaging device

The superconducting magnet device reduces the number of connections within and/or the number of wires leading out of a superconducting coil winding and promptly starts expending the magnetic energy in a superconducting coil operating in a persistent-current mode when the superconducting coil increases in temperature or transitions to normal conductivity. This invention provides a superconducting magnet device that has the following: a superconducting coil connected to an excitation power supply; a persistent-current switch connected to the superconducting coil; a heater that controls the temperature of the persistent-current switch; a current source that is connected in parallel with the persistent-current switch and has a different polarity from the excitation power supply; a driving circuit connected to the heater and the current source; and a signal-inputting means for inputting a signal to the driving circuit. The driving circuit operates the heater and the current source when the signal is inputted thereto.

Superconducting magnet device

This superconducting magnet includes: a superconducting coil that is formed by winding a first superconducting wire rod; a second superconducting wire rod, which is disposed by being thermally in contact with and electrically insulated from the superconducting coil, and which has a superconducting transition temperature that is lower than that of the first superconducting wire rod; voltage terminals that are disposed at a plurality of areas of the second superconducting wire rod; a voltmeter connected to the voltage terminals; and a switch circuit connected to the voltmeter. The switch circuit interrupts a current when receiving an output from the voltmeter, the current being one that is to be supplied to the superconducting coil.

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Tokyo, Japan

Akihisa Miyazoe