Blower cooling fan for electrical equipment has magnetic shaft bearing

摘要

A blower fan has a hub and shaft supported freely by a magnetic bearing in which the shaft is rotated by the application of magnetic forces. The magnetic bearing has a surrounding magnetic ring with a central aperture. The upper and lower ends of the walls around the aperture have a magnetic field strength which is greater than that at the centre of the walls. the blower further has an inner magnetic ring with a central axial mounting hole for a rotating shaft.