Patent ID: 7519191
Filing Date: 2009-04-14
Classification: H04R

Abstract:
1. A loudspeaker, comprising: a hollow frame provided with a first opening and a second opening facing the first opening; a magnet provided inside the frame and having a first pole and a second pole facing the first opening and the second opening, respectively; a plate made of a magnetic material, which is provided in contact with the first pole of the magnet; a yoke made of a magnetic material, which is provided in contact with the second pole of the magnet, forms magnetic flux flow between the first pole and the second pole and has a groove portion on a surface facing the second opening; a first voice coil having a first end located in a magnetic gap provided between the plate and the yoke, a first diaphragm bonded to a second end of the first voice coil and bounded to the first opening of the frame at is outer periphery; a second voice coil having a first end located in the groove portion; and a second diaphragm bonded to a second end of the second voice coil and bonded to the second opening of the frame at its outer periphery.