| 摘要 |
PURPOSE:To elevate the acoustic exchange efficiency, by providing a space where movement of large amplitude is allowed, at the back of the plane diaphragm, connecting the upper part of the coil bobbin fixed to the magnetic gap, to the diaphragm, and supporting the bobbin by plural parts in the shaft direction. CONSTITUTION:A sufficient space is provided at the back of the diaphragm by the side wall 2 which has been formed by raising the circumferential part of the bottom wall 1 of the frame 5, so that the plane diaphragm does not contact with the frame, etc. even in case it moves with large amplitude. And the voice coil 10 is fixed to the magnetic gap 12 of the magnetic circuit of the bottom wall of the frame, and the upper part of the coil bobbin 11 is installed to the diaphragm. Also, the bobbin is supported in the shaft direction by the threads 18a, 18b from plural positions between the reinforced rings 19a, 19b fixed to the bobbin, and the support 20 raised from the bottom wall. |
