| 摘要 |
PURPOSE:To improve the input-resisting property of a dynamic electromechanical converter by improving the effect of cooling in comparison with that only by thermal conduction of a fixed magnetic fluid, by cooling a movable-part driving coil by making use of the convection and thermal conduction of the magnetic fluid. CONSTITUTION:To plate 5 arranged on the outer circumferential part of substrate 2, loudspeaker diaphragm 6 is fitted with support member 7 interposed. Into gap part 8 between the outer circumference of tip part 3a of center pole 3 and the inside of plate 5, bobbin 9 is elongated from diaphragm 6 and around it, voice coil 10 is wound. The tip part of this pole 3 is axially branched into tip part 3a and base part 3b and between the branched tip part 3a and base part 3b, magnetic fluid suction member 11 with branch parts elongated radially from the center part is interposed to form ring-shaped passage 12 whose axial ends are both open to the center cylinder part of member 11. Further, passage 12, suction passage 13 communicating with the center part of gap part 8, and discharge passages 14a and 14b communicating with the end part of gap part 8 are formed to improve the cooling effect of coil 10. |
