Design and characteristic analysis for new structure of bone conduction speaker

This paper presents a new structure of the bone conduction speaker [1]-[5]. The almost structure of bone conduction speaker is the dynamics speaker at present. Therefore, it is difficult to realize miniaturization and light weight. However, the proposed structure is able to improve the sound pressure level (SPL) without increased outside of the diameter dimension because the magnet opposites the magnetic pole of yoke. This speaker operates by flowing the audio current into the voice coil. That reason is the change of attractive force between the magnetic pole of yoke and magnet. Authors revealed various characteristics of this speaker by the electromagnetic field analysis and structural analysis by using the 3-dimensional finite element method (3D-FEM). As the result of electromagnetic field analysis, this speaker operates on the basis of principle. As the result of structural analysis, this speaker makes the audio sound. Consequently, this structure operates as the bone conduction speaker.