| 摘要 |
The fusible element of an electric fuse has a first electrical path, a second electrical path in parallel relation with the first electrical path, a weak spot in the first electrical path which can respond to a potentially-hurtful overcurrent to fuse and thereby form a first arc in the first electrical path, and a weak spot in the second electrical path longitudinally displaced from the weak spot in the first electrical path which can respond to that overcurrent to fuse and thereby form a first arc in the second electrical path. The weak spots form primary arcs as they fuse; and one important function of those primary arcs is to establish the point at which the rate of rise of the overcurrent starts to diminish, while another important function of those primary arcs is to burn the adjacent portions of the respective electrical conducting paths. When enough of the cross sections of those adjacent portions have burned to enable those adjacent portions to fuse, secondary arcs will develop at those adjacent portions; and an important function of those secondary arcs is to provide the desirable current-interrupting characteristics that the series-arranged weak spots of a fusible element can provide when they fuse simultaneously.
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