| 摘要 |
PURPOSE:To improve the durability of a voice coil against the rise of temperature, by dissipating a heat generated in the voice coil efficiently through the provision of a radiator for the voice coil bobbin. CONSTITUTION:A cap 12 made of a material of high thermal conductivity such as Al is fitted to the bobbin 4 so that the opening of the tip of the bobbin 4 is closed. Thus, the cap 12 is utilized as a radiator, the heat generated in a voice coil 5 is dissipated via the bobbin 4 and the cap 12, allowing to improve the durability of the voice coil 5 against the rising temperature. |
