Patent ID: 10113591

Abstract:
A magnetic fluid sealing structure (1) for high-speed rotation for sealing a gap (S) between a shaft member (2) and a housing member (3) disposed around the shaft member (2), which are rotatable, includes: magnetic force generating means (4) which is fixed to the housing member (3) and generates a magnetic force; magnetic pole members (5) disposed on both sides in an axial direction of the magnetic force generating means (4); and a magnetic fluid (7) which is magnetically held between the magnetic pole members (5) and the shaft member (2) by the magnetic force of the magnetic force generating means (4) and seals the gap (S) therebetween, in which the shaft member (2) has a plurality of different material layers concentrically laminated in a radial direction, and an outermost diameter layer (23) of the shaft member (2), which holds the magnetic fluid (7), is made of a magnetic material.