| 摘要 |
PURPOSE:To suppress the resonance and improve the frequency characteristics, by securing a coincidence between the array of metallic crystals and the circumference direction. CONSTITUTION:It is known that the Young's modulus in the array direction of crystals is larger than the Young's modulus in the direction orthogonal to the array direction of crystals. In this connection, the compliance in the direction of center axis of a diaphragm can be increased by securing a coincidence between the array of crystals and the circumference direction of a diaphragm. In other words, an almost fan-shaped metallic material is rolled toward the circumference by means of truncated circular cone type roller. In this case, the array of metallic coincides with the circumference direction of the material. As a result, such diaphragm has an extremely high rigidity in the circumference direction but has a low rigidity in the direction of center axis to obtain an appropriate compliance. Accordingly the interference is reduced for the energy of vibration to suppress a sharp peak dip. |
