Sealing member for ferrofluid seal
US5050891A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 29, 1989 |
| Grant date | Sep 24, 1991 |
| Priority date | — |
| Expiry date | Nov 29, 2009 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S277/919
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
A sealing member for a ferrofluid seal according to the present invention is a sealing member (1) arranged so as to surround a periphery of a working member (5) such as a shaft. The sealing member (1) comprises an annular magnet (2) and an annular pole piece (3), an electrically conductive ferrofluid (6) being provided between the sealing member (1) and the working member (5) to construct an electrically conductive magnetic fluid-sealing member. An inner circumferential surface of the annular magnet (2) is coated with an electrically conductive non-magnetic film (4 ) continuing to the annular pole piece (3) to reduce size of the sealing member (1) and reduce electrical resistance.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.