| 摘要 |
PURPOSE:To amplify an oscillation between short straight lines and to obtain the big oscillation of a diaphragm by providing the diaphragm which is adhered to the another end of a belt and has a projecting part projected in the opposite direction to sound radiating direction from the diaphragm. CONSTITUTION:A field part 15 consisting of a barrel yoke 11, a magnet 12 and a poll piece 13 forms an annular magnetic air gap 14 in which an oscillating body 17 consisting of a voice coil 18 and a voice coil bobbin 19 that winds the voice coil 18 is reciprocated according to an input signal. Therefore, a bearing part 21 and a pulley 20 installed at the upper part of the oscillating body 17 pushes and pulls one set of belts 20A and 20B. An another end of the belt is displaced by double of the displacement of the oscillating body 17 because each end of the set of pulleys 20A and 20B is fixed on a fixing board 28. In other words, a barreled body 23 the another terminal of which is fixed and the plate 24 of a diaphragm 22 are displaced by double to the oscillating direction. |
