Polarized electromagnetic relay

Abstract

A polarized electromagnetic relay is designed to have a minimum height as less as that of an electromagnet block constituting one major part of the relay. The relay includes a base which is formed to receive the electromagnet block and to have a set of fixed contacts. The electromagnet block includes a generally U-shaped yoke with a pair of opposed legs connected by a center core and at least one excitation coil wound around the center core. An armature block is mounted within the base together with the electromagnet block and comprises an elongated armature extending over the opposed pole legs and pivotally supported for movement between first and second positions about a pivot axis. The armature block carries a movable contact for contact selectively with one of the fixed contacts in response to the armature movement between the first and second positions. The armature is magnetically coupled to the pole legs by means of a permanent magnet such that the armature block responds to polarity change in the current energizing the excitation coil to move between the first and second positions. The permanent magnet is disposed in the bottom portion of the base within the plane of the pole legs. The armature block is disposed above the permanent magnet in such a manner that the armature block and the permanent are stacked within the height of the electromagnet block.