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:
Jul. 07, 2020
Filed:
Mar. 30, 2018
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Robert Mitchell, Winchester, MA (US);
Roger B. Fish, Bedford, MA (US);
Shardul S. Patel, Chelmsford, MA (US);
Varian Semiconductor Equipment Associates, Inc., Gloucester, MA (US);
Abstract
A rotary union that includes a heated ferrofluid seal is disclosed. The rotary union includes an inner rotating shaft, an intermediate rotating shaft and an outer rotating shaft. The inner rotating shaft is hollow to allow the flow of cryogenic fluid in one direction. The inner rotating shaft and the intermediate shaft are spaced apart to create a channel for the return of the cryogenic fluid. The intermediate rotating shaft is separated from the outer rotating shaft by a gap so as to reduce thermal conductivity. In this way, the temperature of the outer rotating shaft is greater than the temperature of the cryogenic fluid. A heated ferrofluid seal is disposed between the outer rotating shaft and the housing.