Aisin Seiki Kabushiki Kaisha

Yoshitaka Itoh

Tetsuo Oka

Yousuke Yanagi

Masaaki Yoshikawa

Takeo Yamazaki

Uichiro Mizutani

Yukihiro Kato

Makoto Tsukahara

Yuh Yamada

Atsushi Takagi

A cold head is disposed in an insulating container and cooled by a refrigerator. A superconductor is disposed in the insulating container, contacting the cold head, and is cooled to its superconduction transition temperature or lower by heat conduction. A magnetizing coil is disposed outside the insulating container for applying a magnetic field to the superconductor. Control is performed so that a magnetic field determined considering the magnetic field to be captured by the superconductor is applied. A pulsed magnetic field is applied to the superconductor a plurality of times. Each pulsed magnetic field is applied when the temperature of the superconductor is a predetermined temperature or lower. A maximum pulsed magnetic field is applied at least once in an initial or intermediate stage of the repeated application of pulsed magnetic fields. After that, a pulsed magnetic field equal to or less than the maximum pulsed magnetic field is applied. Pulsed magnetic fields are repeatedly applied while the temperature of the superconductor is lowered. A pulsed magnetic field is applied when the temperature Tof a central portion of the superconductor is the superconduction transition temperature or lower and the temperature of a peripheral portion is higher than T. The temperature of the entire superconductor is brought close to Tto apply another pulsed magnetic field. The magnetizing coil faces at least one of two opposite sides of the superconductor to apply pulsed magnetic fields to the superconductor in its magnetization direction.

Superconducting magnet apparatus and method for magnetizing superconductor

A cold head is disposed in an insulating container and cooled by a refrigerator. A superconductor is disposed in the insulating container, contacting the cold head, and is cooled to its superconduction transition temperature or lower by heat conduction. A magnetizing coil is disposed outside the insulating container for applying a magnetic field to the superconductor. Control is performed so that a magnetic field determined considering the magnetic field to be captured by the superconductor is applied. A pulsed magnetic field is applied to the superconductor a plurality of times. Each pulsed magnetic field is applied when the temperature of the superconductor is a predetermined temperature or lower. A maximum pulsed magnetic field is applied at least once in an initial or intermediate stage of the repeated application of pulsed magnetic fields. After that, a pulsed magnetic field equal to or less than the maximum pulsed magnetic field is applied. Pulsed magnetic fields are repeatedly applied while the temperature of the superconductor is lowered. A pulsed magnetic field is applied when the temperature To of a central portion of the superconductor is the superconduction transition temperature or lower and the temperature of a peripheral portion is higher than T . The temperature of the entire superconductor is brought close to T to apply another pulsed magnetic field. The magnetizing coil faces at least one of two opposite sides of the superconductor to apply pulsed magnetic fields to the superconductor in its magnetization direction.

A cold head is disposed in an insulating container and cooled by a refrigerator. A superconductor is disposed in the insulating container, contacting the cold head, and is cooled to its superconduction transition temperature or lower by heat conduction. A magnetizing coil is disposed outside the insulating container for applying a magnetic field to the superconductor. Control is performed so that a magnetic field determined considering the magnetic field to be captured by the superconductor is applied. A pulsed magnetic field is applied to the superconductor a plurality of times. Each pulsed magnetic field is applied when the temperature of the superconductor is a predetermined temperature or lower. A maximum pulsed magnetic field is applied at least once in an initial or intermediate stage of the repeated application of pulsed magnetic fields. After that, a pulsed magnetic field equal to or less than the maximum pulsed magnetic field is applied. Pulsed magnetic fields are repeatedly applied while the temperature of the superconductor is lowered. A pulsed magnetic field is applied when the temperature T.sub.0 of a central portion of the superconductor is the superconduction transition temperature or lower and the temperature of a peripheral portion is higher than T.sub.0. The temperature of the entire superconductor is brought close to T.sub.0 to apply another pulsed magnetic field. The magnetizing coil faces at least one of two opposite sides of the superconductor to apply pulsed magnetic fields to the superconductor in its magnetization direction.

Superconducting magnet apparatus and method for magnetizing

An Nd-Ba-Cu-O bulk superconductor includes oxide including metallic elements of neodymium (Nd), barium (Ba) and copper (Cu), and has a structure in which fine particles of Nd.sub.4 Ba.sub.2 Cu.sub.2 O.sub.10 (i.e., Nd422) are dispersed uniformly in crystalline grains of NdBa.sub.2 Cu.sub.3 O.sub.x (i.e., Nd123). It is produced by preparing a mixture powder in which an Nd123 powder and an Nd422 powder are present uniformly, thermally treating the mixture powder in a temperature range where the Nd123 powder melts partially at least but the Nd422 powder hardly melts, and gradually cooling the partially melted mixture powder in a temperature range around a solidifying point of the Nd123 powder. It exhibits an enhanced magnetic-field-trapping capability in the regions of low magnetic field, because of the pinning effect resulting from the fine particles of Nd422 dispersed uniformly in the crystalline grains of Nd123.

Neodymium-barium-copper-oxide bulk superconductor and process for

A sensor is provided for detecting a physical quantity such as fluid pressure and acceleration of a mass and converting same into electrical signals. The sensor has a diaphragm made of a metal deformable by the physical quantity, a layered constructed insulating means of an insulating material which is formed on the diaphragm by means of a physical vapor desposition process, wherein the layered constructed insulating means has at least two insulating material layers, a strain gauge formed on the layered constructed insulating means opposite the diaphragm by means of a physical vapor deposition process, and a contact zone on the strain gauge to provide an electrical connection for a physical quantity sensing device to the sensor. Due to the layered construction of the insulating means, the thickness of the insulating means as a whole may be reduced below that of a single layer insulating means and maintain good insulative properties particularly at excessive strain.

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Chiryu, Japan

Yoshitaka Itoh