| 摘要 |
PURPOSE:To improve the output sound pressure level and to eliminate deficiency of damping by arranging a magnet whose shape is rectangular and four sides are in parallel with four sides of cone paper to a recessed part of the cone paper whose outer shape is rectangular to use the magnet of a large volume. CONSTITUTION:A field part 13 comprising the square megnet 10 and square plates 11, 12 is fitted to the center of the square frame 1 so that each side is in parallel. A coil of a voice coil 7 supported by a damper 6 is inserted in a gap of the field part 13. Then the square cone paper 8 is fitted in matching with the outer peripheral of the frame 1 and the center is bonded to the tip of the voice coil 7. Through the structure above, the space in the recessed face of the cone paper 8 is used effectively as the space for the field part 13 and the strong field part 13 having the magnet 10 large in volume is used. |
