POLARIZED ELECTROMAGNET

摘要

PURPOSE:To permit an armature to be reliably latched at a stable position and a polarized electromagnet to be lower-priced and being miniaturized by placing two permanent magnets having different maximum magnetic energies together with their magnetizing directions allowed to agree with each other to form a compound permanent magnet. CONSTITUTION:An armature is a H-shaped one-body construction comprising two parallel magnetic plates 1 whose central portions are bridged by two compound permanent magnets 2 and which are secured by a resin frame having a shaft hole in its center and made of glass fiber-containing nylon or the like. Each of the compound permanent magnets 2 is formed by placing together a high-power permanent magnet 2a made of cerium cobalt magnet, samarium cobalt magnet or the like having a large maximum magnetic energy and a low-power permanent magnet 2b of barium ferrite or the like having a small maximum magnetic energy, with their magnetizing directions allowed to agree with each other. Said procedure permits a more compact polarized electromagnet to be obtained at a lower cost.