Electromagnetic relay with symmetric reaction.

摘要

An electromagnetic relay includes a coil (21) wound around a core both of whose ends (23a,23b) project therefrom. A yoke extends parallel thereto, and each of its ends is formed with two pole pieces (27) which extend towards and lie one of each side of an end of the core with a certain gap being defined therebetween. A connecting member extends parallel to the core and the yoke and is mounted so as to be movable transversely, and means (33-44) are provided for establishing and breaking some electrical connection according to such transverse movement. There are provided two armature pieces (29), one for each end of the core and both fixed to the connecting member. Each armature piece includes a permanent magnet plate (32) and two plates of magnetic material (31) fixed to it so as generally to form a C shape with one of the magnetic material plates being magnetized to be a north pole and the other a south pole. Each of the two plates of magnetic material is inserted on one side of an end of the core between it and the opposing one of the pole pieces of the yoke, into the gap therebetween. The directions of magnetization of the armature pieces are oppositely oriented. Thereby, when the relay switches over, it does so without generating any off center jerking, and thus its mounting to a base is improved. Also the quality of the magnetic circuit, and the manufacturability of the relay, are improved.