| 摘要 |
<p>CONCAVE DIAPHRAGM FOR ELECTRO-ACOUSTIC TRANSDUCER An electro-acoustic transducer, adapted to constitute part of an alarm unit, includes a magnetic diaphragm adjacent the core of the transducer. The case for the transducer is so configured that it forces the diaphragm into a concave shape, whereby the diaphragm operates extremely efficiently and provides other advantages over a planar diaphragm.</p> |
