Patent ID: 8382118

Claim:
A magnetic fluid sealing device for incorporation into an apparatus having rotatable components; the sealing device comprises: a housing mounted to the apparatus; a shaft rotatably mounted in the housing; the shaft having an outer surface that defines a first portion and a second portion along its longitudinal axis (x); the outer surface of the shaft in the second portion having at least one groove that encircles the shaft; a magnetic structure having an inner surface; the structure being coupled to the housing; the inner diameter of the structure sized to encircle the outer surface of the shaft along its first portion, thereby creating a first radial gap; a magnetic fluid located in the first gap; one rolling element bearing having an inner ring and an outer ring; the outer ring being coupled to the housing; the inner ring having an inner diameter sized to encircle the outer surface of the shaft along its second portion, thereby creating a second radial gap; and a compressible ring located in the groove of the shaft; the compressible ring adapted to fill a part of the second gap and contact the inner ring of the rolling element bearing; and a hardenable locking material filling a part of the second gap, the hardenable locking material extending axially beyond the groove; wherein the compressible ring radially aligns and centers the shaft along its longitudinal axis (x) with the rolling element bearing; wherein when the locking material hardens, it couples the shaft and compressible ring to the inner ring of the rolling element bearing; wherein the magnetic fluid establishes a seal between the magnetic structure and the shaft.