The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 11, 1990
Filed:
Apr. 27, 1989
Applicant:
Inventor:
Akira Yamamura, Tokyo, JP;
Assignee:
Nippon Ferrofluidics Corporation, Tokyo, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
F16C / ;
U.S. Cl.
CPC ...
384133 ; 384245 ;
Abstract
A bearing for a vacuum device having an annular permanent magnet disposed about a rotatable shaft which has one end exposed to low pressure and the other end exposed to atmospheric pressure in which the rotatable shaft has a spherical member formed on the high pressure end for mating with a concave bearing surface having a magnetic fluid interposed therebetween and the rotatable shaft has a plurality of grooves formed thereon for aligning with a plurality of rings formed on an annular pole piece in which a magnetic fluid is disposed between the rings and grooves, which can be formed on the shaft, for providing a high pressure seal.