Patent ID: 6973194
Filing Date: 2005-12-06
Classification: H04R

Abstract:
1. A speaker, comprising: a frame; a magnetic circuit fixed to the frame; a diaphragm fixed to the frame so as to be capable of vibrating in a predetermined direction; a driving force transmitting member connected to the diaphragm; and a damper for supporting the driving force transmitting member, wherein the magnetic circuit is positioned between a first plane and a second plane, the first plane being parallel to the diaphragm and defined as a plane with which at least a portion of the magnetic circuit is in contact, and the second plane being parallel to the diaphragm and defined as a plane with which at least a portion of the magnetic circuit is in contact, the driving force transmitting member has a region in which a voice coil is formed, the driving force transmitting member is structured so as to transmit to the diaphragm, a driving force, in the predetermined direction, caused by an effect of an electric current flowing through the voice coil and a magnetic flux generated from the magnetic circuit, the magnetic circuit includes a first magnetic circuit portion, a second magnetic circuit portion, and a magnetic gap defined by the first and second magnetic circuit portions, the first magnetic circuit portion includes a magnet having a rectangular parallelepiped shape, a first plate fixed onto an upper surface of the magnet, and a second plate fixed onto a lower surface of the magnet, the second magnetic circuit portion includes a yoke, a side surface of the first magnetic circuit portion is connected onto the frame, a side surface of the second magnetic circuit portion is connected onto the frame, the magnet and the yoke face each other, and the magnetic gap includes a first magnetic gap, which is defined by the first plate and the yoke and through which the magnetic flux generated by the magnet passes, and a second magnetic gap, which is defined by the second plate and the yoke and through which the magnetic flux generated by the magnet passes.