| 摘要 |
PURPOSE:To obtain a dynamic speaker having a plane diaphragm of a wide band and high performance, by improving the structure of the plane diaphragm and thus increasing the limit of a piston oscillation region. CONSTITUTION:A plane diaphragm 10' is a composite diaphragm in which the skins 14 and 15 made of the aluminum alloy of 20mu thickness are stuck on both surfaces of a core 13 made of the foamed acrylic material having 3mm. thickness. The skin 14 on the surface contains plural linear rolls 16 extending radially from the axial center; while one or plural concentric corrugations 17 are provided concentrically with the plane diaphragm to the skin 15 on the rear surface, respectively. The flexural rigidity is increased in both directions of diameter and circumference by these rollers 16 and corrugations 17. Thus the occurrence can be reduced for many oscillation modes. As the surface density of the diaphragm has virtually no change, the ratio of the flexural rigidity/surface density is increased. As a result, the high-band resonance frequency that causes a divided oscillation is increased. |
