| 摘要 |
PURPOSE:To improve the emitting ability of a resonant sound, and to miniaturize a resonator by driving a vibrator by a vibrator driving device so as to cancel reaction from the resonator, and raising Q of the resonator extremely high. CONSTITUTION:When a drive signal is given to the transducer 22 of the vibrator 20 from 8 negative impedance driver driving device 30, the transducer 22 electro- mechanical-converts it, and reciprocates a diaphragm 21 right and left in a figure, and turns it into a mechanical sound. Here, since the device 30 is provided with a negative impedance driving function, the internal impedance peculiar to the transducer 22 is reduced effectively. Accordingly, the transducer 22 drives the diaphragm 21 as responding faithfully to the drive signal from the device 30, and gives driving energy to a Helmholtz resonator 10. At this time, the reaction from air in the cavity of the resonator 10 acts upon the right surface side of the diaphragm 21, but the device 30 drives the vibrator 20 so as to cancel this reaction. Accordingly, the air in the resonator 10 resonates, and the sound of sufficient sound pressure is resonant-emitted from a resonant emitting part as shown by an arrow mark. |
