Characteristics of the Magnetic Gear Using a Bulk

A magnetic gear which can transmit force without contact has operational benefits of requiring neither vibration, noise, nor lubrication. Still, its transmission force is considerably smaller than a mechanical gear. Strong magnets are needed to improve magnetic gear transmission force. For this purpose, a magnet formed by the pinning effect in a bulk superconductor might have magnetic flux density several times stronger than rare-earth permanent magnets. We propose a noncontact magnetic gear using a bulk high-Tc su- perconductor. In this paper, a three-dimensional electromagnetic field analysis program has been developed to analyze character- istics of the proposed gear. Two superconducting magnetic gears with different magnet configuration are manufactured, and their characteristics are measured. The analysis and the experiment ex- plore the possibility of a magnetic gear using the pinning magnet formed in the superconductor.