Magnetic seal for magnetic particle clutches and brakes

摘要

A novel seal for a magnetic particle brake or clutch of the type having a rotatable shaft made of a non-magnetic material. The seal comprises (a) one or more permanent magnets adapted to be mounted in close proximity to but not engaging the adjacent surface of the rotatable shaft or a movable member that is exposed to the magnetic particles, and (b) means for mounting the one or more magnets and protecting them from excessive external magnetic fields.