The Design and Application of Electrodynamic Actuaor

• Main Authors: Kun-Sen Lin, 林坤森
• Other Authors: Tai-Yan Kam
• Format: Others
• Language: zh-TW
• Published: 2003
• Online Access: http://ndltd.ncl.edu.tw/handle/69322015050154127559

碩士 === 國立交通大學 === 機械工程系 === 91 === This paper is focused on the design of small circular electrodynamic actuators and the sound pressure simulation of small planar loudspeakers. There are two types of circular electrodynamic actuators which have either an outter magnet or inner magnet. We used 2-D finite element model to analyze the flux distribution in the air gap of the magnet assembly and determine the maximum flux density. Then we studied the effects of different design parameters on the distribution of magnetic flux and used these analytical data together with the neural network method to establish a tool for designing actuators. We made several loudspeakers by assembling actuators , suspensions , and planar vibration plates and measured their amplitudes at the first resonant frequencies Fs and SPL curves. At the first resonant frequency , loudspeaker’s dynamic behavior is same as a one degree of freedom vibration system. Therefore we used a one degree of freedom vitration system to simulate the loudspeaker and caculate the amplitude at Fs. Then we can simulate the SPL curves of loudspeaker by using the one degree of freedom sound pressure theory. We discussed the differences between the theoretical and experimental results and identified the factors which can have influences on the performance of the speakers.