05062140 is referenced by 23 patents and cites 15 patents.

In a speaker which comprises a diaphragm having a vibrating portion and an annular conductive portion, a current feeding coil facing the conductive portion with a predetermined gap therebetween, and a magnetic circuit including a top plate, a magnet and a yoke plate to which the current feeding coil is attached; the diaphragm is formed so that an electrical resistance of its conductive portion is lower than an electrical resistance of its vibrating portion.

Title
Induction speaker
Application Number
7/340034
Publication Number
5062140
Application Date
April 18, 1989
Publication Date
October 29, 1991
Inventor
Shiro Tsukamoto
Kanagawa
JP
Hiroyuki Sogawa
Kanagawa
JP
Kiyofumi Inanaga
Kanagawa
JP
Agent
William S Frommer
Alvin Sinderbrand
Assignee
Sony Corporation
JP
IPC
H04R 25/00
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