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. 10, 2013
Filed:
Aug. 26, 2010
Applicant:
Kuldip Raj, Merrimack, NH (US);
Inventor:
Kuldip Raj, Merrimack, NH (US);
Assignee:
Ferrotec (USA) Corporation, Santa Clara, CA (US);
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
G01R 27/08 (2006.01);
U.S. Cl.
CPC ...
Abstract
A failure indicator seal includes a nonmagnetic housing, a plurality of annular pole pieces having distal ends, the plurality of annular pole pieces disposed within the nonmagnetic housing, an annular, non-conducting magnet disposed between the pole pieces, a predefined quantity of magnetic fluid disposed between each of the distal ends of the plurality of annular pole pieces and the rotary shaft of a rotary feedthrough forming a plurality of magnetic fluid O-ring seals, and means for measuring resistance through the plurality of annular pole pieces, the plurality of magnetic fluid O-ring seals and the rotary shaft.