Variable resonance acoustic transducer
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorKurt G. Eyster
Life of this patent
Estimating the term…
Abstract
A transducer assembly is provided for projecting acoustic signals into a medium. The assembly includes a support member having first and second layers of piezoelectric material mechanically linked to the support member. The first and second layers are joined to electrical drive circuitry such that one layer receives a driving voltage signal while the other layer receives the driving voltage with a stiffening voltage. The transducer assembly can use both the 3-1 and 3-3 drive modes. Multiple configurations are supported, and both bender bar and slotted cylinder configurations are shown.
Claims20
A transducer assembly comprising:
- a support member;
- a first layer of piezoelectric material mechanically joined to said support member for providing strain in a first desired direction that affects said assembly, said first layer having first layer electrodes;
- a second layer of piezoelectric material mechanically joined to said support member for providing strain in a second desired direction that affects said assembly, said second layer having second layer electrodes;
- electrical drive circuitry joined to said first layer electrodes and said second layer electrodes, said electrical drive circuitry being configured to provide a driving voltage to one of said first layer electrodes and said second layer electrodes and being configured to provide the driving voltage with a stiffening voltage to the other of said first layer electrodes and second layer electrodes, wherein said electrical drive circuitry further comprises a controller configured to calculate and adjust the magnitude of said stiffening voltage based on a desired transducer assembly resonance frequency and environmental conditions.
A transducer assembly comprising:
- a support member having a hollow tubular outer shell having a slot extending lengthwise therethrough, the outer shell having an interior surface;
- a first layer of piezoelectric material segments, each having a major arcuate surface and two radial faces, and configured to provide strain in a first desired direction that affects said assembly, said first layer segments having first layer electrodes on the radial faces;
- a second layer of piezoelectric material segments, each having a major arcuate surface joined to said support member interior surface and two radial faces, said second layer having a minor arcuate surface opposite said major arcuate surface, said second layer being configured to provide strain in a second desired direction that affects said assembly, said second layer segments having second layer electrodes on the radial faces;
- an insulating layer positioned between said first layer major arcuate surface and said second layer minor arcuate surface;
- electrical drive circuitry joined to said first layer electrodes and said second layer electrodes, said electrical drive circuitry being configured to provide a driving voltage to one of said first layer electrodes and said second layer electrodes and being configured to provide the driving voltage with a stiffening voltage to the other of said first layer electrodes and second layer electrodes wherein said first layer electrodes are positioned to provide the voltage perpendicular to the first desired direction, and said second layer electrodes are positioned to provide the voltage perpendicular to the second desired direction.
Dependencies are inferred from the claim text.