Impact-reinforced piezocomposite transducer array

• US 6,806,622 B1
• Filed: 10/20/2000
• Issued: 10/19/2004
• Est. Priority Date: 10/22/1999
• Status: Expired due to Fees

• Current Assignee: Channel Technologies Group, LLC
• Original Assignee: Material Systems, Inc.
• Inventors: Glynn, James M., Schmidt, Gerald E.
• Primary Examiner(s): Dougherty, Thomas M.
• Application Number:
  US09/693,034
• Time in Patent Office: 1,460 Days
• Field of Search: 310/327, 310/334, 310/369
• US Class Current: 310/334
• CPC Class Codes: B06B 1/067 which is used as, or combined with, an impedance matching layer
• CPC Class Codes: G10K 11/006 Transducer mounting in underwater equipment, e.g. sonobuoys
• CPC Class Codes: H04R 1/44 Special adaptations for subaqueous use, e.g. for hydrophone
• CPC Class Codes: H04R 17/005 using a piezoelectric polymer

Abstract

An impact-reinforced piezocomposite transducer array comprises a load supporting structure having a plurality of cells, each of said cells comprises a piezocomposite transducer element. The load supporting structure comprises a honeycomb structure having a plurality of multi-sided cells or the structure comprises a plurality of cylindrical cells. The piezocomposite element includes a plurality of piezoceramic rods encapsulated in a polymeric matrix to form a 1-3 composite body. The transducer array may be used as a hydrophone or a transmitter in a rugged environment such as on the hull of an icebreaker ship.

Claims

1. An acoustic transducer array comprising:

a honeycomb structure having a plurality of cells, each of said cells comprises a piezoelectric transducer;

each piezoelectric transducer comprises a stack having at least one piezocomposite element;

each piezocomposite element includes a plurality of piezoceramic elements, said piezoceramic elements being arranged parallel to each other;

said plurality of piezoceramic elements of said piezocomposite element being encapsulated in a polymeric matrix forming said piezocomposite element;

a front planar surface and a back planar surface of said piezocomposite element comprise an electrically conductive layer; and

a soft pressure release material is disposed around each stack except on a surface of said stack facing a front surface of said acoustic transducer array.

2. The acoustic transducer array as recited in claim 1 wherein said transducer array comprises means disposed adjacent to said plurality of cells for providing waterproofing of said acoustic transducer array.

3. The acoustic transducer array as recited in claim 1 wherein said honeycomb structure comprises a plurality of multi-sided cells.

4. The acoustic transducer array as recited in claim 1 wherein said honeycomb structure comprises a plurality of cylindrical cells.

5. The acoustic transducer array as recited in claim 1 wherein said honeycomb structure comprises a matrix of a plurality of strips attached together at cross-over points, said strips being made of an impact-resistant material.

6. The acoustic transducer as recited in claim 1 wherein said honeycomb structure comprises a molded or drilled-out structure made of an impact-resistant material.

7. The acoustic transducer array as recited in claim 1 wherein said piezocomposite element comprises a 1-3 connectivity configuration.

8. The acoustic transducer array as recited in claim 1 wherein said piezocomposite element comprises a 2-2 connectivity configuration.

9. The acoustic transducer array as recited in claim 1 wherein each piezocomposite element is separately wired for sensing as a single element.

10. The acoustic transducer array as recited in claim 1 wherein said piezocomposite element is wired for sensing in a phased array configuration.

11. The acoustic transducer array as recited in claim 1 wherein each piezocomposite element is separately wired for transmitting as a single element.

12. The acoustic transducer array as recited in claim 1 wherein each piezocomposite element is separately wired for transmitting in a phased array configuration.

13. The acoustic transducer array as recited in claim 1 wherein said stack comprises said piezocomposite element, an acoustic matching layer adjacent to a front surface of said piezocomposite element, and a stiffening layer adjacent to a back surface of said piezocomposite element.

14. The acoustic transducer array as recited in claim 1 wherein said stack comprises said piezocomposite element and a stiffening layer adjacent to a back surface of said piezocomposite element.

15. The acoustic transducer array as recited in claim 1 wherein said stack comprises said piezocomposite element and an acoustic matching layer adjacent to a front surface of said piezocomposite element.

16. The acoustic transducer array as recited in claim 1 wherein said stack comprises wires extending from said front planar surface electrically conductive layer and from said back planar surface electrically conductive layer of said piezocomposite element for wiring said cells in a predetermined manner for operation of said acoustic transducer as a sensor array.

17. The acoustic transducer array as recited in claim 1 wherein said stack comprises wires extending from said front planar surface electrically conductive layer and from said back planar surface electrically conductive layer of said piezocomposite element for wiring said cells in a predetermined manner for operation of said acoustic transducer as a transmitter array.

18. The acoustic transducer array as recited in claim 1 wherein said stack comprises a first piezocomposite element disposed adjacent to a second piezocomposite element, an acoustic matching layer adjacent to a front surface of said first piezocomposite element, and a stiffening layer adjacent to a back surface of said second piezocomposite element.

19. The acoustic transducer array as recited in claim 1 wherein said stack comprises a piezocomposite element, a first acoustic matching layer positioned adjacent to a front surface of said piezocomposite element, a second acoustic matching layer positioned adjacent to said first acoustic matching layer, and a stiffening layer adjacent to a back surface of said piezocomposite element.

20. A method of providing an acoustic transducer array for operation in a rugged environment comprising the steps of:

providing a honeycomb structure having a plurality of cells, each of said cells comprises a piezoelectric element;

providing in each piezoelectric transducer a stack having at least one piezocomposite element;

including a plurality of piezoceramic elements, in each piezocomposite element, said piezoceramic elements being arranged parallel to each other;

forming said piezocomposite element by encapsulating said plurality of piezoceramic elements of said piezocomposite element in a polymeric matrix;

providing an electrically conductive layer on a front planar surface and a back planar surface of said piezocomposite element; and

disposing a soft pressure release material around each stack except on a surface of said stack facing a front surface of said acoustic transducer array.

21. The method as recited in claim 20 wherein said method comprises the step of providing means disposed adjacent to said plurality of cells for waterproofing said acoustic transducer array.

22. The method as recited in claim 20 wherein said step of providing a honeycomb structure comprises the step of said honeycomb structure having a plurality of multi-sided cells.

23. The method as recited in claim 20 wherein said step of providing a honeycomb structure comprises the step of said honeycomb structure having a plurality of cylindrical cells.

24. The method as recited in claim 20 wherein said step of providing a honeycomb structure comprises the step of providing a matrix of a plurality of strips attached together at cross-over points said strips being made of an impact-resistant material.

25. The method as recited in claim 20 wherein said step of providing a honeycomb structure having a plurality of cells comprises the step of providing at least one piezocomposite element having a 1-3 connectivity configuration in each of said cells.

26. The method as recited in claim 20 wherein said step of providing a honeycomb structure having a plurality of cells comprises the step of providing at least one piezocomposite element having a 2-2 connectivity configuration in each of said cells.