| 摘要 |
PURPOSE:To provide a speaker device for silencing of an active noise control system which eliminates the atm. pressure difference of the air on both front and rear of a diaphragm of a speaker for silencing, allows the diaphragm of the speaker for silencing to make exact vibration, prevents the mechanical fatigue of the speaker for silencing and is capable of producing a sufficient sound power in a frequency region to be silenced. CONSTITUTION:This speaker device for silencing of the active noise control system is constituted to silence the noises propagating in a duct 1 by radiating the sounds of the same sound pressure as the sound pressure of the sound waves of the noises propagating in the duct 1 and the antiphase of the phase of these noises from the speaker 3 for silencing toward the sound waves of the noises in the duct 1 and interfering both sound waves. The speaker device for silencing is constituted by including the speaker 3 for silencing which is disposed in the aperture of the wall surface of the duct 1 so as to radiate the sounds into the duct 1, a speaker box 21 which houses the speaker 3 for silencing therein and a communicating pipe 22 which is disposed to communicate the internal space of the speaker box 21 and the internal space of the duct 1 and resonates at the frequency to be silenced. |
