Omni-directional radiator for multi-transducer array

• US 20100119090A1
• Filed: 11/04/2009
• Published: 05/13/2010
• Est. Priority Date: 11/12/2008
• Status: Active Grant

• Current Assignee: Curtis E. Graber
• Original Assignee: Curtis E. Graber
• Inventors: Graber, Curtis E.
• Granted Patent: US 8,218,398 B2
• Time in Patent Office: Days
• US Class Current: 381/190
• CPC Class Codes: H04R 1/403 loud-speakers
• CPC Class Codes: H04R 1/44 Special adaptations for subaqueous use, e.g. for hydrophone
• CPC Class Codes: H04R 17/00 Piezoelectric transducers; Electrostrictive transducers piezoelectric or electrostrictive elements in general H10N30/00; details of piezoelectric or electrostrictive motors, generators or positioners H10N30/00
• CPC Class Codes: H04R 2201/401 2D or 3D arrays of transducers

Abstract

An omni-directional acoustic horn for applications in a liquid transmission medium deploys a plurality of transducers distributed along an interior face of the horn to radiate against an opposed surface. The arrangement mimics operation at a greater depth of submergence to depress development of acoustic cavitation bubbles.

Claims

1. An acoustic radiator comprising:

an interior face;

an interior boundary opposing the interior face;

a central core connecting the interior face to the interior boundary; and

a plurality of transducers distributed along the interior face and oriented to radiate into the interior boundary.

2. The acoustic radiator of claim 1, further comprising a half shell and a disk baffle to support the interior boundary and the interior face, respectively, the half shell and the disk baffle defining a toroidal waveguide providing for omni-directional radiation of sound from a mouth.

3. The acoustic radiator of claim 2, wherein the interior face is one of first and second major surfaces of a disk baffle, with first and second interior boundaries opposing the first major surface and a second major surface of the disk baffle, respectively, and plurality of transducers being distributed on the first and the second major surfaces of the interior baffle.

4. The omni-directional acoustic radiator of claim 3, further comprising:

the transducers being piezoelectric devices.

5. The omni-directional acoustic radiator of claim 4, further comprising:

successive sub-arrays of transducers including greater numbers of transducers with increasing proximity to the mouth.

6. The omni-directional acoustic radiator of claim 5, further comprising:

at least a first radial baffle extending to the mouth of a toroidal waveguide.

7. The omni-directional acoustic radiator of claim 6, further comprising:

plurality of radial baffles defining a plurality of signal channels within each toroidal waveguide.

15. The acoustic radiator of claim 2, including a plurality of toroidal waveguides stacked into a waveguide.

8. An acoustic radiator comprising:

an arcuate mouth;

a waveguide extending from the mouth to a base, the waveguide being defined by first surface and a second opposed surface;

a plurality of acoustic transducers distributed along one of the first and the second opposed surface; and

drive circuitry for the acoustic transducers for synchronously reinforcing a sound wave propagating along the length of the waveguide from the base to the arcuate mouth by operating those of the plurality of acoustic transducers on the first surface.

9. The acoustic radiator of claim 8, wherein the plurality of acoustic transducers reinforce the sound wave keeping a stable frequency spectrum.

10. The acoustic radiator of claim 9, further comprising:

the plurality of acoustic transducers being organized into sub-arrays defined by distance of the acoustic transducers in a sub-array from the arcuate mouth; and

a ratio of the surface area of the acoustic transducers in any sub-array relative to the length of the arc of the sub-channel for the sub-array being a constant.

11. The acoustic radiator of claim 10, further comprising;

a second waveguide with the acoustic transducers being mounted in a baffle providing major surfaces for the first surface for both the first and second sound channels.

12. The acoustic radiator of claim 11, further comprising:

ring dampening elements positioned between the first and second surfaces of the sound channels.

13. An acoustic radiator comprising:

an arcuate waveguide, which may be extended through a full circle to form a toroidal waveguide;

the arcuate waveguide including first and second facing interior surfaces forming wave propagation boundaries;

a plurality of acoustic transducers arranged in a constellation along one of the first and second facing interior surfaces;

the plurality of acoustic transducers being oriented to direct sound into the remaining facing interior surface; and

the waveguide terminating at a mouth.

14. The acoustic radiator of claim 13, further comprising:

radial baffles dividing the arcuate waveguide into radial channels.

16. The acoustic radiator of claim 14, including a plurality of toroidal waveguides stacked into a waveguide.