摘要 |
The present invention provides a delayed-fusion fuse by which its predetermined durability can be reliably ensured, and its stable pre-arcing time-current characteristics can be obtained, even when a current exceeding the steady-state current such as a motor lock current frequently flows in the fuse. The delayed-fusion fuse includes a pair of electric connecting sections formed on both sides of a fusible section having a narrow fusing portion made of an electrically conductive metal. Also, the delayed-fusion fuse includes a metallic chip made of low fusing point metal for absorbing heat generated in the fusible section, and a covering and adhering section for holding the metallic chip on the fusible section. A thin metallic layer forms a solid solution with the low fusing point metal, where the solid solution requires an energy of formation which is higher than that of the formation of a solid solution made of the electrically conductive metal and the low fusing point metal. This thin metallic layer is interposed between a surface of the covering and adhering section and a surface of the low fusing point metallic chip. Specifically, the thin metallic layer is provided on a surface of the fusible section in the form of a plating layer.
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