Loudspeaker using an electro-active device
US7224813B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2000 |
| Grant date | May 29, 2007 |
| Priority date | — |
| Expiry date | Sep 5, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S310/80
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A loudspeaker comprising: a support, a sound-generating element mounted to the support for vibration to generate sound; and an electro-active device coupled between the support and the sound-generating element for vibrating the sound-generating element in response to an electrical signal. The electro-active device comprises a structure extending along a minor axis which extends in a curve around a major axis parallel to the vibration direction of the sound-generating element, the structure comprising successive electro-active portions arranged with electrodes to bend around the minor axis on activation in response to application of the electrical signal to the electrodes, and coupled together such that bending of successive portions causes concomitant rotation of adjacent portions around the minor axis adding incrementally along the minor axis, which rotation causes concomitant change of the axial length of the structure along the major axis.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.