Magnetic bearing having permanent magnet assemblies with repulsive bearing surfaces

Abstract

The magnetic bearings make use of magnet assemblies with a high magnetic field gradient. The magnet assemblies use two permanent magnets with opposite polarization in a Kittel open domain structure. The basic factor of magnetic separation is the magnetic force, which acts on a particle of the substance and which is proportional to the magnetic susceptibility of the substance, the value of the magnetic induction B and the value of the gradient ∇B of the applied magnetic field. Therefore, increasing the sensitivity and selectivity of magnetic separation will require use of the highest possible values of magnetic induction B and magnetic field gradient ∇B, or their united factor—the product B∇B. The magnetic assembly have repulsive magnetic systems each having two juxtaposed permanent magnetswith opposite magnetization in the form of a Kittel open domain structure. In such an system, near the edges of the faces of the joining magnets, a strong magnetic stray field appears and the value of the product B∇B reaches 10mT/m. To concentrate the magnetic stray field shieldsare provided on top of the two magnetswith a gapbetween the shields at the joint of the two magnetsforming zones of high magnetic field gradientwith increased magnitude for the product B∇B.