Self-activating ferrofluid seal and method

摘要

A self-activating ferrofluid-seal apparatus for a memory-disc-drive shaft, which seal apparatus comprises a ring magnet and a pair of pole pieces which form a cavity therebetween, a closed loop of a plastic tubular container with ferrofluid positioned within the cavity, and a penetration clamp to penetrate the plastic container prior to installation of the shaft element.