CPC H04R 11/02 (2013.01) [H04R 7/18 (2013.01); H04R 31/006 (2013.01); H04R 2400/07 (2013.01)] | 20 Claims |
1. A hearing-device loudspeaker comprising:
a magnetic-flux-carrying housing;
an acoustic sealing structure separating an interior of the housing into a back volume and a front volume connected to a sound port of the housing;
a first coil disposed in the front volume, the first coil having a first winding about a corresponding first magnetic core;
a second coil disposed in the back volume, the second coil having a second winding about a corresponding second magnetic core,
opposing surfaces of the first and second magnetic cores having opposite magnetic polarities and generating a magnetic field in a gap between the first and second magnetic cores, and the first and second coils configured to produce counter-rotating currents in the first and second windings in response to a common excitation signal applied to the first and second coils; and
a magnetic-flux-carrying armature fastened to the acoustic sealing structure and movably located in the gap,
wherein sound is emitted from the sound port when the armature moves the acoustic sealing structure in response to the common excitation signal.
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