MAGNETIC CIRCUIT FOR SPEAKER DEVICE AND SPEAKER DEVICE

摘要

A thin magnetic circuit for driving a flat voice coil which allows a reduction in the thickness of a speaker device.  A magnetic circuit (20) for a speaker device is provided with magnetic gaps (20G) arranged in the direction of vibration of a voice coil (30).  Among magnetic pole surfaces partitioned by a voice coil facing the magnetic gaps, a magnetic pole surface on one side is provided with a first magnetic pole surface (20X) comprising a magnetic body including a magnet (21) and also with  a second magnetic pole surface (20Y) comprising a plate-like magnetic body magnetically joined to the magnet.  In the plate-like magnetic body, a joint surface, which is located between the plate-like magnetic body and the magnetic body forming the first magnetic pole surface, and the second magnetic pole surface are formed in a step-like shape, and the first magnetic pole surface and the second magnetic pole surface have substantially the same height.