In accordance with the CAFE program, for lighter-wight of a loudspeaker, the weight and performance of loudspeakers were analyzed, and thereby a lighter-weight loudspeaker has been developed.
This loudspeaker consists of a light-weight magnetic circuit with a higher magnetic-flux utilization rate and a high-rigidity light-weight frame.
In the first place, this paper describes the weight-contributing-rate of a loudspeaker by analyzing the weight constitution of conventional loudspeakers.
In the next place, for the magnetic circuit with the highest weight-contributing-rate, a light weight magnetic circuit structure which enhances the magnetic-utilization-rate of the magnet through the C A E analysis and the axis of easy magnetization of the Nd-Fe-B system magnet with high energy-product are described.
In the third place, for the frame with the second highest weight contributing-rate, the structural analysis by the finite element method as well as the light-weight frame with thinner wall and high-strength steel plate is described. Finally, the performance comparison between the newly developed light-weight loudspeaker with a combination of a light-weight magnetic circuit and a light-weight frame, and the conventional type is described. The above mentioned newly developed loudspeaker realizes 1/3 weight of the conventional type.