发明名称 |
Electromagnetic transducer and portable communication device |
摘要 |
<p>An electromagnetic transducer includes: a first diaphragm disposed in a vibratile manner; a second diaphragm provided in a central portion of the first diaphragm, the second diaphragm being formed of a magnetic material; a yoke disposed in a position opposing the first diaphragm; a center pole provided on a face of the yoke that opposes the first diaphragm; a coil substantially surrounding the center pole; a magnet substantially surrounding the coil; and a thin magnetic plate provided between the magnet and the first diaphragm, an inner periphery of the thin magnetic plate being in overlapping relation to an outer periphery of the second diaphragm. <IMAGE></p> |
申请公布号 |
EP0999722(A2) |
申请公布日期 |
2000.05.10 |
申请号 |
EP19990120984 |
申请日期 |
1999.11.04 |
申请人 |
MATSUSHITA ELECTRIC INDUSTRIAL CO., LTD. |
发明人 |
USUKI, SAWAKO;SAIKI, SHUJI |
分类号 |
H04R9/00;H04R13/02;(IPC1-7):H04R9/06 |
主分类号 |
H04R9/00 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|