SPEAKER DIAPHRAGM AND ITS PRODUCTION

摘要

PURPOSE:To decrease the weight and to increase the bending rigidity of a speaker diaphragm, by using a composite material obtained by filling the micro hollow spheres into a metal. CONSTITUTION:An alloy silumine 3 of 88.3% aluminum and 11.7% silicon is melted, and metallic sodium or sodium fluoride is added as a viscosity adding material. Then a ''Sirasu-sand'' balloon 4 (0.4 specific gravity) having a smaller specific gravity than the molten silumine 3 is scattered and mixed to obtain a composite base materia after cooling. This composite base material is heated again and poured into a mold of a diaphragm shape to obtain a diaphragm 1 after cooling and solidifying stages.