Patent ID: 8160292

Claim:
A loudspeaker comprising a first magnet having a first pole and a second pole, the polarity of the second pole being opposite to that of the first pole; a second magnet having a third pole of the same polarity as the first pole and a fourth pole of the same polarity as the second pole, the second magnet being disposed so that the third pole opposes the first pole face to face; a third magnet having a fifth pole of the same polarity as the first pole and a sixth pole of the same polarity as the second pole, the third magnet being disposed so that the direction containing the fifth pole and the sixth pole is perpendicular to the line connecting the first pole and the third pole, the sixth pole is positioned at the side that is closer to the first and the third poles, and provides magnetic gaps in a space formed with respect to the first magnet and with respect to the second magnet, respectively; a voice coil disposed in the magnetic gaps; a diaphragm supporting the voice coil; a plate made of non-magnetic material, the plate supporting the first magnet at a portion other than the first and the second poles, and a second magnet at a portion other than the third and the fourth poles; and a magnetic member magnetically coupling the fifth pole with the second pole and with the fourth pole, respectively.