Magnetic fluid retainer, and shaft sealer employing same

摘要

Apparatus for sealing a magnetic shaft includes a magnetic housing having a throughbore with a stepped enlargement at one end, a pair of annular disk-shaped yokes spaced apart by an axially magnetized permanent magnet positioned in the stepped enlargement and surrounding the shaft, and magnetic fluid in the gaps between the yokes and the shaft. The outside diameter of one yoke is spaced from the magnetic housing and is smaller than the outside diameter of the other yoke, while the larger yoke abuts the magnetic housing at its outside diameter. A plastic, non-magnetic member can separate the smaller diameter yoke from the magnetic housing.