| 摘要 |
<p>13 An audio-frequency electromechanical vibrator having a flat hollow case with a thin cover plate, a flat ring-shaped permanent magnet axially magnetized and a flat annular drive coil unit. The magnet and the coil unit are disposed in the case coaxial with one another and with an axial space therebetween. The magnet is fixedly mounted on the bottom of the case and the coil unit is elastically supported to the case by a spring plate. Whereby the vibrator can generate strong and neat vibration without noise generation corresponding to a comparatively higher frequency component in an audio signal applied to the coil unit. In an aspect, the case may be formed to have a central boss portion on which the spring plate is supported coaxial with the boss portion. The coil unit and the magnet are disposed coaxial with, and around, the boss portion.</p> |
