Patent ID: 6542617
Filing Date: 2003-04-01
Classification: H04R

Abstract:
A speaker constructed in a manner that a voice coil bobbin is attached to an inner circumferential portion of a cone type diaphragm while a voice coil is wound on the voice coil bobbin and inserted into a magnetic gap, whereinthe voice coil bobbin is formed of an electrically conductive material and the voice coil is attached to the voice coil bobbin by a soft bonding agent, so that the diaphragm is driven by the voice coil bobbin having the voice coil attached thereto, wherein said soft bonding agent is selected so that in a high frequency range a bonding strength of said soft bonding agent is lowered, whereby said voice coil and said voice coil bobbin become unattached from each other and said voice coil drives said voice coil bobbin to move relative to said voice coil, so that the diaphragm is driven by the voice coil bobbin with the voice coil separated therefrom, whereby the speaker operates as an electromagnetic induction speaker.