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:
Mar. 13, 1984
Filed:
Apr. 30, 1982
Hiroshi Tamama, Saitama, JP;
Yukio Ozawa, Saitama, JP;
Jingo Miyazaki, Tokyo, JP;
Hiroshi Ito, Saitama, JP;
Toyohiro Kinoshita, Tokyo, JP;
Japanese National Railways, Tokyo, JP;
Abstract
A sealing device for a ship's propeller shaft installed around the propeller shaft in which longitudinally spaced annular iron pole blocks, and circularly spaced permanent magnets fixed between the blocks are mounted in a cylindrical housing surrounding the propeller shaft, and a magnetic fluid fills gaps between the magnets and the annular iron pole blocks and either a liner mounted about the shaft or the shaft itself. The magnetic fluid serves as a sealant and completes a magnetic circuit which maintains a well defined thickness of magnetic fluid sealant and a high pressure seal even under great mechanical stress, thereby minimizing frictional power loss and wear to the propeller shaft or sleeves which are conventionally shrink-fitted thereto.