METHOD FOR MAKING A MAGNETIC FLUID SEAL AND MAGNETIC FLUID SEAL WITH PRECISE CONTROL OF FLUID VOLUME AT EACH SEAL STAGE

摘要

A method for making a magnetic fluid seal, the method comprising: applying ferromagnetic fluid within at least one of a plurality of grooves formed within a rotatable shaft or a pole ring; freezing the ferromagnetic fluid placed within the at least one of the plurality of grooves, wherein the ferromagnetic fluid changes from a liquid state to a solid state, whereby the ferromagnetic fluid is immobilized; placing the shaft or the pole ring within an opening of a housing of the magnetic fluid seal before the ferromagnetic fluid changes from the solid state to the liquid state. A magnetic fluid seal includes a pole ring having an inner diameter, a rotatable shaft having an outer diameter, the rotatable shaft configured to extend along the inner diameter of the pole ring between an atmosphere side and vacuum side, at least one magnet coupled to the pole ring, the at least one magnet configured to emit a magnetic field having a strength and a shape, and grooves formed on either the inner diameter of the pole ring or the outer diameter of the shaft, the grooves capable of containing ferromagnetic fluid. The ferromagnetic fluid contained the grooves varies so as to improve the performance of the magnetic fluid seal.