| 摘要 |
PURPOSE:To obtain a low-frequency high power transmitter with small size, light weight and excellent sound radiation efficiency by providing a piston sound radiator to an active columnar body using a piezoelectric ceramic device and a lever via a connecting rod. CONSTITUTION:The active columnar body 31 is formed by using a pizoelectric ceramic and longitudinal vibration is excited by applying a voltage thereto. In order to apply excellent rigid body rotation of a lever 34, a U-shaped base 32 has large rigidity with respect to the longitudinal displacement of the colum nar body 31. A hinge 33 has a comparatively large rigidity with respect to longitudinal displacement has is flexible to the deflection displacement to rotate the lever 34 easily. In converting the mass of the lever 34 and the body 36 with respect to the body 31, since the equivalent mass is nearly the 2nd power of the displacement expanding rate, even when the actual mass of the lever 34 and the body 36 is small, since the equivalent mass is increased, remarkable low frequency constitution is attained. |
