Method of making a polarized electromagnetic relay

Abstract

A polarized electromagnetic relay includes a base, an electromagnet with a coil and a pair of pole pieces extending perpendicularly from the end of said coil, a balanced armature and spring system which when actuated pivots between two fixed contact points and a permanent magnet inducing the same magnetic poles in both of said pole pieces and providing an opposite pole in closely adjacent relationship to the central portion of the armature. A movable contact spring is fixedly connected to the armature, said spring forming contact arms at either armature end portion. Further, a flexible movable braid connects the movable contacts on said movable spring to each other and to a movable contact terminal. A pair of retaining tabs extending from a central bobbin flange engaging corresponding recesses at the lateral sides of the armature limits the movement of the armature in two directions as well as its rotation. This feature eliminates the need for a torsion spring and allows the contact forces to be higher if necessary. Two identical coils wound in a common direction are provided as the means for actuation. Armature transfer will occur by either applying a voltage pulse across the appropriate coil, or by toggling the voltage pulse polarity across the two coils connected in series.