Patent ID: 7532736
Filing Date: 2009-05-12
Classification: H04R

Abstract:
1. A speaker comprising: a concave frame having a lower surface on a lower portion thereof, and an opening on an upper portion thereof; a diaphragm having an inner periphery, an outer periphery, and a bottom surface, said diaphragm disposed in said opening of said frame and fixed to an edge of said opening by a first edge; a voice coil on said bottom surface of said diaphragm; a suspension holder having an inner periphery and an outer periphery, said suspension holder disposed inside of said frame at said bottom surface of said diaphragm and fixed to said frame by a second edge; and a magnetic circuit including: wherein: said first and second edges are spaced apart, and substantially symmetrical with respect to a space therebetween; at least a portion of said magnetic circuit is disposed outside of said frame and below said lower surface of said frame; said outer periphery of said ring-shaped magnet extends beyond a center of a width of said second edge; said inner periphery of said ring-shaped plate and said columnar protrusion extend into said frame from said lower surface to an area within said frame midway between said lower surface and said opening, so as to form a magnetic gap between said inner periphery of said ring-shaped plate and said outer periphery of said columnar protrusion; at least a portion of said voice coil is movably disposed inside of said magnetic gap; and said inner periphery of said suspension holder and said inner periphery of said diaphragm are fixed to a portion of said voice coil which is outside of said magnetic gap.