The Research Of Broadband Bender Transducers

The bender transducer is a common low-frequency transducer, which has the advantages of small size. But due to a single vibration modal, transducer bandwidth usually is narrow, cannot satisfy actual application requirements. Therefore this paper developed a kind of broadband bender transducer, which have a compact size, wideband and double-end radiation performance, through multiple bending modals coupling broaden bandwith.First of all, according to characteristics of the classic analytical method of the transducer and Rayleigh method which is usually used to analysis the ordinary disc bender transducer, analyze advantages and disadvantages are used for designing the broadband bender transducer. Then it can be determined using finite element method for transducer simulation analysis.Secondly, finite element software ANSYS is adopted to analysis the broadband bender transducer. Changing transducer model structures sizes one by one, calculating acoustic properties of the transducer, then the relationships between size and transducer performance can be emerged, and then the best structure size can be shown. The simulation results show that transducer's±1.5dB can cover 11kHz～30kHz range, with the maximum SVL over 140.3dB.Finally, the prototype of the transducer is produced according to the best structure size. Then the transducer's impedance characteristics, SVL and acoustic pressure directivity are measured. The measured results show that transducer's±3dB can cover 11kHz～30kHz range, with the maximum SVL over 141.7dB.The experimental results of prototype transducer shows that using multiple bending modals coupling can broaden bandwith usefully, and achieve wideband with a compact size.