Patent ID: 7235907
Filing Date: 2007-06-26
Classification: F16C

Abstract:
1. Axial magnetic bearing apparatus in which a rotary disc made of a magnetic material is fixedly attached to a rotating shaft, while a pair of electromagnetic stators in each of which a ring-like electromagnetic coil for generating magnetomotive force is inserted into a coil slot are fixed to casings respectively so as to be located on opposite sides of said rotary disc with suitable very small distances, and on the basis of an output signal of a displacement sensor for measuring axial displacement of said rotating shaft, magnetic attraction force is made to act between said rotary disc and each of said electromagnetic stators so as to bear said rotating shaft in a target position distant from said electromagnetic stators and in non-contact therewith, said thrust magnetic bearing apparatus being characterized in that slits large enough to increase radial magneto-resistance are provided at several places in outer circumferential portions of said electromagnetic stators.