In this alloy type thermal fuse, molten metal of a low-melting alloy piece 2 is provided between the surface ends of lead conductors 1, 1 and cooled down under the cooling rate fast enough for surface open, and cooled and solidified at a stage before the surface tension of the molten metal balances with the surface tension of the surface of the lead conductor 1, thereby achieving deformation performance of the surface tension in remelting. リード導体1、1の表面端部間に低融点合金片2の溶湯を配給し、表面開放の充分に速い冷却速度のもとで冷却して、当該溶湯の表面張力と当該リード導体1の表面の表面張力とが平衡する前の段階で冷却凝固させて、再溶融に対し表面張力変形性能を保有させた。 - 特許庁