Superconducting bearing device

Abstract

A superconducting bearing device comprises a permanent magnet portion fixedly mounted on a rotary body concentrically therewith, and a superconductor opposed to the magnet portion and spaced apart therefrom radially of the rotary body, the magnet portion being so disposed that the rotation of the rotary body does not alter the magnetic flux distribution around the axis of rotation of the rotary body, the superconductor being disposed at a position which is spaced apart from the magnet portion by a distance permitting a predetermined quantity of magnetic flux thereof to penetrate into the superconductor and which does not permit the rotation of the rotary body to alter the penetrating magnetic flux distribution. The magnet portion comprises a plurality of annular permanent magnets arranged at a spacing along the axis of rotation of the rotary body and an annular yoke of ferromagnetic material interposed between each two adjacent magnets. Each of the magnets is magnetized to opposite polarities at its respective opposite ends in the direction of the axis of rotation, each two adjacent magnets being magnetized to the same polarity at their ends opposed to each other with the yoke interposed therebetween.