Method and apparatus for forming a dynamic magnetic seal using magnetorheological fluid
US7156724B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 15, 2004 |
| Grant date | Jan 2, 2007 |
| Priority date | — |
| Expiry date | Apr 1, 2025 |
Classification
- Technology area (CPC F)Mechanical Engineering; Lighting; Heating
- CPC primaryF16J15/43
- WIPO fieldMechanical elements
- WIPO sectorMechanical engineering
Abstract
An arcuate, preferably cylindrical, magnetic shunt bar supports a plurality of pin magnets having alternate north and south orientations, defining a ring-shaped array of magnets of alternating orientation. The magnet free ends opposite the shunt bar are positioned to conform closely to the shape of a surface to be sealed, forming a narrow gap therebetween containing a multi-polar magnetic field extending beyond the free ends in a direction substantially orthogonal to the surface. The axes of the magnets may be disposed at any desired angular orientation to the surface. Magnetorheological fluid (MRF) in the gap is magnetically stiffened and held as a dynamic seal. The arrangement is useful as a shaft seal, wherein the seal surface passes axially through the array, and also as a wiper for MRF from a carrier surface wherein the surface passes by the array.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.