Magnet keeper

From Wikipedia, the free encyclopedia
Jump to: navigation, search

A magnet keeper, or armature is a ferromagnetic bar made from soft iron or steel which is placed across the poles of a permanent magnet to help preserve the strength of the magnet by completing the magnetic circuit; it is particularly useful for magnets which have a low magnetic coercivity, such as Alnico magnets.

Keepers also have a useful safety function as they stop external metal being attracted to the magnet.