| 摘要 |
PROBLEM TO BE SOLVED: To provide a circular flat plate type speaker by a thin type light weight doughnut-shape diaphragm which can carry out the whole plane driving of a doughnut type circular flat plane diaphragm with a center aperture, suppress the generation of circular nodes and diameter direction nodes in a resonance mode of divided vibration over all desired frequency bands, and make sound pressure frequency characteristics smooth in a full range. SOLUTION: The circular flat plate type speaker of the doughnut-shape diaphragm installs a plurality of small circular voice coils on a plane of the diaphragm which are arranged in circular vibration regions by the same interval on a concentric circle whose diameter is smaller than the outer diameter of the doughnut-shape diaphragm, installs a plurality of thin type magnetic circuits which form magnetic gaps in which respective voice coils can be inserted on inner planes of the frame which holds the diaphragms using edges, and establishes a radius of the concentric circle so that the arrangement density of all voice coils in an outer side circle part and an inner side circle part of the concentric circle becomes uniform. COPYRIGHT: (C)2010,JPO&INPIT
|
