Search International and National Patent Collections

1. (WO2013160669) TRANSDUCERS WITH IMPROVED IMPEDANCE MATCHING

Pub. No.:    WO/2013/160669    International Application No.:    PCT/GB2013/051028
Publication Date: Fri Nov 01 00:59:59 CET 2013 International Filing Date: Wed Apr 24 01:59:59 CEST 2013
IPC: B06B 1/06
G10K 11/02
H04R 1/28
H04R 17/00
Applicants: HIWAVE TECHNOLOGIES (UK) LIMITED
Inventors: EAST, James
HARRIS, Neil John
Title: TRANSDUCERS WITH IMPROVED IMPEDANCE MATCHING
Abstract:
A transducer (140) having a mechanical impedance over an operative frequency range and having a desired power coupling (145) to a load over the operative frequency range comprises a piezoelectric device (141) having a frequency distribution of modes in the operative frequency range; and an overmould (143). The overmould (143) is arranged to surround at least part of the piezoelectric device (141); and the parameters of the overmould (143) are selected to provide a required impedance matching between the mechanical impedance of the transducer (140) and the mechanical impedance of the load. An alternative transducer comprises a mounting means for holding a discrete portion of at least a part of the periphery of the piezoelectric device wherein the parameters of the mounting means are selected to provide a required boundary condition for the periphery of the piezoelectric device whereby the desired power coupling between the transducer and the load is provided.