To provide an electroacoustic transducer capable of obtaining sufficient sound pressure, even when it is made compact/thin.
An electroacoustic transducer includes a diaphragm 3, having a periphery as a fixed end, a coil 4 having an axis perpendicular to the diaphragm 3 and attached centrally to the diaphragm 3, and a direct current magnetic field generator fixed in position as spaced apart from the coil 4 by a gap provided axially of the coil 4. The diaphragm 3 is driven by applying to the coil 4 a magnetic flux, emitted from a surface of the direct current magnetic field generator that faces the coil 4. The direct current magnetic field generator includes a ring-shaped outer magnet 5, located coaxially with the axis of the coil 4 and magnetized in a direction parallel to the axis, and an inner core 6 including a ferromagnet and located in the center hole of the outer magnet 5.
KOSUDA KAZUYUKI
JPS61216599A | 1986-09-26 | |||
JPS5743689A | 1982-03-11 | |||
JPH01122691A | 1989-05-15 | |||
JP2005286984A | 2005-10-13 | |||
JP2006173997A | 2006-06-29 | |||
JP2004072647A | 2004-03-04 | |||
JPS5746394A | 1982-03-16 | |||
JP2003169393A | 2003-06-13 | |||
JP2003125486A | 2003-04-25 | |||
JPH09331596A | 1997-12-22 |
Yoshiko Sugioka
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