| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an electrodynamic speaker provided with a magnetic circuit arranged on a concave surface side of a small or thin type cone-shaped diaphragm as well as a magnetic circuit used for the speaker and, in particular, to provide an electrodynamic speaker that is suitable to be mounted on acoustic apparatuses of vehicles, displays or the like. <P>SOLUTION: In an electrodynamic speaker, a support member formed of a magnetic body includes a shaft part connected to a magnetic circuit at its one end and a flange part extending from the other end side of the shaft part to communicate with a frame. The shaft part extending inside a bobbin has an outer diameter smaller than the inner diameter of the bobbin. The flange part is provided to extend from the other end of the shaft part in a direction orthogonal to the direction in which the shaft part extends, with the outer diameter of the flange part being larger than that of the magnetic circuit. The magnetic circuit is a repulsion magnetic circuit including a repulsion magnet in which surfaces with the same magnetic polarity are disposed to face each other so that they sandwich a pole piece together with a main magnet, and which communicates with one end of the shaft part of the support member. <P>COPYRIGHT: (C)2012,JPO&INPIT |
