| 摘要 |
PURPOSE:To allow an electromagnetic core to endure a large number of times of repetition of switching operation of an electromagnetic contactor, by providing around a through hole in an end plate irregularities which produce a high frictional force between the head of a rivet and the end plate when one end of the rivet is caulked. CONSTITUTION:In a movable core 4, end plates 7 of a soft steel sheet are disposed on both sides of a laminate 6 formed by laminating silicon steel sheets. A rivet 8 is received in a hole 11 extending through the laminate 6 and the end plates 7 and is caulked to integrate the laminate 6 and the end plates 7. For example, corrugated irregularities 12 extending circumferentially are radially provided in a part of one side surface of one end plate 7 along the fringe of the through hole 11. Even if an impact resulting from a collision between the movable and fixed cores is transmitted to the electromagnetic core, it shows a large resistance to sliding between the inner surface of the head 9 of the rivet 8 and the end plate 7 and therefore maintains a high mechanical strength. Thus, the electromagnetic core can sufficiently endure several millions of times of repetition of the switching operation of the electromagnetic contactor. |
