| 摘要 |
An electric horn (50) having a diaphragm (14) connected to a ferromagnetic plunger (16) is driven by an electromagnetic coil (36) to cause vibrations of the diaphragm (14) at the resonant frequency of the diaphragm and plunger combination. A solid state driver (58) has a timer (70) tuned essentially to the frequency of the diaphragm assembly and controls the driver power output to effect coil energization to drive the diaphragm movement synchronously with the timer frequency. The driver output stage comprises a power MOSFET (80) or a Darlington pair. |
