Journal of the Korean Society for Precision Engineering (한국정밀공학회지)

Korean Society for Precision Engineering (한국정밀공학회)
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Investigation on Vibration Characteristics of Micro Speaker Diaphragms for Various Shape Designs

마이크로 스피커 진동판의 형상설계에 따른 진동특성 고찰

  • Kim, Kyeong Min (Graduate School of NID Fusion Technology, Seoul National Univ. of Science and Technology) ;
  • Kim, Seong Keol (Dept. Mechanical System Design Engineering, Seoul National Univ. of Science and Technology) ;
  • Park, Keun (Dept. Mechanical System Design Engineering, Seoul National Univ. of Science and Technology)
  • 김경민 (서울과학기술대학교 NID 융합기술대학원) ;
  • 김성걸 (서울과학기술대학교 기계시스템디자인공학과) ;
  • 박근 (서울과학기술대학교 기계시스템디자인공학과)
  • Received : 2013.05.17
  • Accepted : 2013.07.02
  • Published : 2013.08.01
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Abstract

Micro-speaker diaphragms play an important role in generating a desired audio response. The diaphragm is generally a circular membrane, and the cross section is a double dome, with an inner dome and an outer dome. To improve the sound quality of the speaker, a number of corrugations may be included in the outer dome region. In this study, the role of these corrugations is investigated using two kinds of finite element method (FEM) calculations. Structural FEM modeling was carried out to investigate the change in stiffness of the diaphragm when the corrugations were included. Modal FEM modeling was then carried out to compare the natural frequencies and the resulting vibrational modes of the plain and corrugated diaphragms. The effects of the corrugations on the vibration characteristics of the diaphragm are discussed.

Keywords

References

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