Lightweight Low Frequency Loudspeaker for Active Noise Control

Abstract

The invention described herein is a low-mass, light-weight sound generator with particularly good performance at mid and low audio frequencies. It is expected to find principal use in applications where mass is of crucial importance. It is capable of delivering the high acoustic levels, as required for sound generation or active sound control. The present invention uses a generally planar acoustic membrane as a diaphragm, the diaphragm being in tension and attached at its outer edge to a support frame which provides a soft boundary condition to the acoustic diaphragm. In a preferred embodiment, the support structure is an inflatable toroidal tube of rubber or rubber-like material. A polymer membrane is attached to the support structure by heat sealing the membrane in place. A voltage is applied to a piezoelectric bender-type actuator, which imparts axial displacement to a region of the diaphragm, causing resonance of the diaphragm in the desired frequency range.

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Document Details

Document Type
Technical Report
Publication Date
Mar 02, 2001
Accession Number
ADD019760

Entities

People

  • Robert D. Corsaro

Organizations

  • United States Department of the Navy

Tags

Communities of Interest

  • Energy and Power Technologies
  • Ground and Sea Platforms
  • Space

DTIC Thesaurus Topics

  • Acoustic Impedance
  • Actuators
  • Boundaries
  • Displacement
  • Frequency
  • Frequency Bands
  • Generators
  • Heat Sealing
  • Inventions
  • Lightweight
  • Loudspeakers
  • Materials
  • Measurement
  • Patent Applications
  • Resonance
  • Sound Generators
  • Sound Pressure

Readers

  • Electrical Engineering
  • Materials Science and Engineering.
  • Speech Processing/Speech Recognition.