| 摘要 |
PURPOSE:To obtain the speaker of a wide frequency band and a high efficiency, by using the diaphragm folded into accordion pleats as the sound emitting source. CONSTITUTION:When a bias voltage is applied across diaphragm 6 and fixed electrode 7 and 8 and the phase-inverted signal input is applied to fixed electrode groups 7 and 8, diaphragm 6 is subjected to push-pull driving by electrostatic force. If a positive voltage and a negative voltage are applied to front fixed electrode group 7 and rear fixed electrode group 8 respectively, pleats opening forward are opened from the balanced position to suck air, and pleats opening backward are closed from the balanced position to emit air. If voltages are applied to electrode groups reversely, air is emitted forward and is sucked from the back. |
