Seal for a joint or juncture – Seal between relatively movable parts – Close proximity seal
Reexamination Certificate
2005-12-20
2005-12-20
Pickard, Alison (Department: 3676)
Seal for a joint or juncture
Seal between relatively movable parts
Close proximity seal
C384S446000
Reexamination Certificate
active
06976682
ABSTRACT:
An apparatus and method are provided for sealing an outer surface170of a shaft175to an inner surface165of a hub160.The seal includes a magnet155,with top and bottom pole pieces260, 265,and a ferrofluid270magnetically held in a gap275between the pole pieces260, 265,and the hub160or the shaft175.The top pole piece260has a cross-section that is L-shaped, with a horizontal portion260aparallel to the magnet155and a shorter vertical portion260bfacing the shaft175.In one version, the vertical portion260bor the portion of the shaft175facing it is contoured to provide a flux gradient that axially concentrates the ferrofluid270in the gap275.In another aspect, a catcher335is provided to reduce loss of ferrofluid270when the ferrofluidic seal185used to form an outside seal. In yet another aspect, a stationary ferrofluidic seal345is provided for sealing a stationary shaft350to a rotating hub355.
REFERENCES:
patent: 1014850 (1912-01-01), Richardson
patent: 1879625 (1932-09-01), Mendenhall et al.
patent: 1879627 (1932-09-01), Mendenhall et al.
patent: 2133879 (1938-10-01), Thearle
patent: 2665929 (1954-01-01), Sawyer
patent: 2834618 (1958-05-01), Wiltse
patent: 3091469 (1963-05-01), Matt
patent: 3567231 (1971-03-01), Albert
patent: 3620584 (1971-11-01), Rosensweig
patent: 3694042 (1972-09-01), Rabenhorst
patent: 4054293 (1977-10-01), Hoeg et al.
patent: 4200296 (1980-04-01), Stahl et al.
patent: 4304411 (1981-12-01), Wilcock et al.
patent: 4357021 (1982-11-01), Raj et al.
patent: 4357024 (1982-11-01), Raj
patent: 4407518 (1983-10-01), Moskowitz et al.
patent: 4426088 (1984-01-01), Ernst
patent: 4444398 (1984-04-01), Black, Jr. et al.
patent: 4455026 (1984-06-01), Pinkus et al.
patent: 4478424 (1984-10-01), Raj
patent: 4506895 (1985-03-01), Raj
patent: 4527802 (1985-07-01), Wilcock et al.
patent: 4565379 (1986-01-01), Ballhaus
patent: 4604229 (1986-08-01), Raj et al.
patent: 4681328 (1987-07-01), Ritter et al.
patent: 4717266 (1988-01-01), Hart, Jr. et al.
patent: 4830384 (1989-05-01), Raj et al.
patent: 4973064 (1990-11-01), Hosoya
patent: 5007513 (1991-04-01), Carlson
patent: 5009436 (1991-04-01), Endo et al.
patent: 5018751 (1991-05-01), Raj et al.
patent: 5050891 (1991-09-01), Ishikawa
patent: 5051853 (1991-09-01), Hosoya
patent: 5061868 (1991-10-01), Iwazaki et al.
patent: 5108198 (1992-04-01), Nii et al.
patent: 5161902 (1992-11-01), Fujii
patent: 5165701 (1992-11-01), Koba
patent: 5238254 (1993-08-01), Takii et al.
patent: 5267737 (1993-12-01), Cossette et al.
patent: 5271631 (1993-12-01), Yokouchi et al.
patent: 5473484 (1995-12-01), Dunfield et al.
patent: 5617272 (1997-04-01), MacLeod et al.
patent: 5660397 (1997-08-01), Holtkamp
patent: 5675199 (1997-10-01), Miyakoshi et al.
patent: 5676472 (1997-10-01), Solomon et al.
patent: 5876037 (1999-03-01), Ishizaki et al.
patent: 6029978 (2000-02-01), Pelstring et al.
Byl Marten Fredrick
LeBlanc Jeffry Arnold
Macleod Donald James
Notingham Robert Alan
Pelstring Robert Michael
Morrison & Foerster / LLP
Patel Vishal
Pickard Alison
Seagate Technology LLC
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