| 摘要 |
The horn includes a support casing (1 to 3) in which the peripheries of two facing diaphragms (10, 11) are restrained, a chamber (12) of variable volume being defined between the diaphragms (10, 11) and communicating with a sound-emission duct (50, 51, 70). Respective, opposed ferromagnetic armatures (17, 18) are connected to the diaphragms (10, 11). When a control solenoid (15) is excited by an intermittent current, it causes the armatures (17, 18) to move in opposition and the diaphragms (10, 11) to vibrate in counterphase. |
