| 摘要 |
PURPOSE:To attain considerable cost down by using a material obtained by cladding a metal with high conductivity such as copper and aluminium to a magnetic substance only by required thickness to form a cap and ring and mounting the cap and the rink on a pole piece and a top plate. CONSTITUTION:A ring-like magnet 9 is joined with the surface of a pole piece plate 8, a top plate is joined with the surface of the magnet 9 and a cap-like part 12 obtained by press-molding a material to which a copper plate or an aluminium plate is claded like a cap is mounted on the tip of the pole piece 11. As to a speaker using a cap consisting of copper or the like, the size of the magnet 9 is generally expanded by one rank to compensate the magnetic flux density of a magnetic cap part. Thereby, said speaker includes two material cost up elements, i.e. cost up due to the cap and cost up due to the enlargement of scale of the magnetic circuit, as compared to a capless speaker.
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