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:
Apr. 04, 1989
Filed:
Sep. 25, 1985
Thomas J Black, Jr, Lowell, MA (US);
Ferrofluidics Corporation, Nashua, NH (US);
Abstract
A ferrofluid seal apparatus and a method of assembling the seal apparatus, the seal apparatus comprising a housing, an annular permanent magnet and at least one annular pole-piece element, and a sealing ring to secure and seal the permanent magnet and the pole-piece element within the housing, the sealing ring having an inwardly extending shoulder at one radial end, to retain the permanent magnet and pole piece within the sealing ring. The sealing ring is composed of a deformable material and retains, by compressive force, the permanent magnet and pole piece, by press-fitting the sealing ring into the annular space between the outer surface of the permanent magnet and the annular pole piece and the inner surface of the housing, to secure the permanent magnet and pole piece within the housing.