Mitsubishi Denki Kabushiki Kaisha

Tatsuya Oue

Akinori Yamasaki

Moriaki Takechi

Akihiro Harada

Yuji Shimada

Takahiro Tanoue

Sigenori Kuroda

A superconducting magnet apparatus has two or more divided superconducting coils successively arrayed in series and a magnetic shield. The divided superconducting coils arrayed in the axial direction are successively electrically connected in series, and protective diodes are connected between two connection points symmetrically-located with respect to the center of the serially-connected superconducting coil array as a reference.

Superconducting magnet apparatus with a magnetic shield

An electromagnetic apparatus has a housing with a cavity in which a uniform magnetic field is created by a magnetic coil disposed in the housing. The electromagnetic apparatus also has one or more containers for containing magnetic substances for adjusting the intensity distribution of the magnetic field in the cavity so as to obtain a uniform intensity, and clamps attached to the housing for detachably mounting the containers. During adjustment of the magnetic field in the cavity, a container is removed from the clamps, magnetic substances are added or removed, then the container is mounted in the clamps again.

Electromagnetic apparatus

Superconducting magnet device

An electromagnet having a magnetic shield, in which dummy holes generally equal in shape to a hole conventionally provided for a service port are formed in a pair of end plates of a magnetic shield. The holes formed in each of the end plates are in equal radial-direction positions and are arranged in the circumferential direction at equal angular intervals, and the positions of the holes formed on the two end plates are symmetric on the center point of the electromagnet and/or the plane containing the center point and perpendicular to the center axis. Portions of the end plates in the vicinity of the holes are increased in thickness to compensate for the loss of the magnetic material due to the formation of the holes.

Electromagnetic having magnetic shield

A superconducting magnet device includes a superconducting coil for generating a magnetostatic field, and a pulsating magentic field generating coil disposed on the inner diameter side of the superconducting coil. An inner cylinder of a thermal shielding tank located between the superconducting coil and the pulating magentic field generating coil is maintained at a temperature equal to or lower than the liquid nitrogen temperature. The inner cylinder is made of a superconductor which becomes superconductive at a temperature equal to or higher than the liquid nitrogen temperature. Further, a heating wire for heating the inner cylinder which is in a superconductive state to cause it to become normal conductive is provided on the inner cylinder of the thermal shielding tank in a direction in which it cuts across an induced current loop generated by the excitation of the static magnetic field.

An electromagnet comprising a magnetic field coil and a substantially cylindrical magnetic shield coaxially disposed around the field coil for defining a magnetic circuit therearound. The magnetic shield comprises a hollow cylindrical magnetic yoke with ring-shaped end plates at its opposite ends. The magnetic yoke's cylindrical wall has a cross-sectional area effective for accommodating the magnetic flux generated by the magnetic field coil. The magnetic yoke has a pair of thicker wall sections at first diametrically opposite positions, and a pair of thinner wall sections a second diametrically opposite positions separated by 90 degrees from the first diametrically opposite positions. The thicker and the thinner wall sections are thicker and thinner, respectively, than a mean required wall thickness which is a wall thickness necessary for providing to the magnetic yoke a cross-sectional area for effectively accommodating the magnetic flux generated by the magnetic field coil.

Electromagnet with a magnetic shield

In a superconducting magnet apparatus comprising a liquid helium container accommodating a superconducting magnet in liquid helium and a vacuum insulating vessel surrounding the liquid helium container via a vacuum layer, the improvement wherein power supply leads inserted into a wiring tube fitted through the vacuum insulation vessel and the liquid helium container are formed of a superconductor having a critical temperature not lower than the temperature of liquid nitrogen.

Growing community of inventors

Ako, Japan

Tatsuya Oue