| 摘要 |
PURPOSE:To provide a magnetic circuit for a speaker with good productivity by providing a cylindrical raising vertically to a bottom surface on the central hole of the bottom surface of a frame and connecting the internal peripheral side face thereof to the external peripheral side face of a top plate. CONSTITUTION:The cylindrical raising 11 vertical to the bottom surface is formed on the central hole of the bottom surface of the frame 16 to make the major diameter dimension of the top plate 14 the same as an internal peripheral diameter. A leading part 12 is disposed in the external periphery of the frame 16 vertically to the bottom surface. The frame 16 is connected to the top plate 14 to press a resin magnet 4 into a recessed part of the raising 11 and the leading 12. Then, an annular ferrite magnet 15, the top plate 14 and the resin magnet 4 are bonded to a bottom plate 13 to complete. The top plate 14 is connected to the frame 16 by a suaging and the resin magnet 4 is inserted under a pressure, so that the productivity is improved and the frame 16 is connected to the external periphery of the top plate 14 and the resin magnet 4 is inserted under the pressure, so that a leaked magnetic flux is reduced.
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