| 摘要 |
PURPOSE:To prevent intrusion of iron powder during work, by enclosing a gap of a plate of a magnetic circuit assembly with synthetic resin film, bonding the assembly with a speaker frame and cutting off the synthetic resin afterward. CONSTITUTION:On the surface of a magnetic circuit assembly 1, i.e., the surface of a plate 3, a synthetic resin film 6, 10-200mum thick is overlapped. The film 6 is formed with a size equal to or slightly larger than that of the surface of the plate 3 and perforation lines 6a are provided at the center in almost the same shape as a gap 3a. Thus, the film 6 is thermally bonded or fixed with a tape on the surface of the plate 3 and a speaker frame 7 is fitted to the magnetic circuit assembly 1 with screws 8. The iron powder produced in this work is dropped on the film 6. After blowing off the iron powder, the center of the film 6 is cut off along the perforation lines 6a and the diaphragm is fitted. |
