Acoustic transducer panel

• US 6,438,242 B1
• Filed: 09/07/1999
• Issued: 08/20/2002
• Est. Priority Date: 09/07/1999
• Status: Expired due to Fees

• Current Assignee: The United States of America As Represented By The Secretary of Agriculture
• Original Assignee: the united states of america as represented by the secretary of the navy
• Inventors: Howarth, Thomas R.
• Primary Examiner(s): Le, Huyen
• Assistant Examiner(s): Harvey, Dionne
• Application Number:
  US09/404,721
• Time in Patent Office: 1,078 Days
• Field of Search: 381/162, 381/163, 381/173, 381/191, 381/431, 381/339, 381/190, 181/161, 181/149, 310/324, 310/800
• US Class Current: 381/190
• CPC Class Codes: G10K 9/121 Flextensional transducers
• CPC Class Codes: H04R 15/02 Resonant transducers, i.e. adapted to produce maximum output at a predetermined frequency
• CPC Class Codes: Y10S 310/80 Piezoelectric polymers, e.g. PVDF

Abstract

An electro-acoustic transducer in which a plurality of cymbal-type electro-acoustic actuators are disposed in mechanical and electrical parallel between a pair of stiff plates. The resultant transducer resonates at a lower frequency than the cymbals, with a greater generated force.

Claims

1. An electro-acoustic transducer for transducing acoustic signals at or below a pre-selected acoustic frequency, comprising:

a plurality of cymbal-shaped acoustic elements; and

a pair of plates;

wherein each of said plurality of cymbal-shaped acoustic elements is disposed in mechanical parallel arrangements between said pair of plates, and each of said elements is further disposed in electric parallel arrangements with respect to one another; and

wherein the size of each of said pair of plates and the number of said elements is selected to be driven in piston mode by said plurality of cymbal-shaped acoustic elements at or below said pre-selected frequency.

2. The transducer of claim 1, wherein said preselected acoustic frequency is the resonant frequency of said transducer.

3. The transducer of claim 1, wherein said transducer comprises a water tight sealant surrounding said plates.

4. An electro-acoustic transducer capable of being driven in a piston mode comprising:

a plurality of cymbal-shaped acoustic elements; and

a pair of plates;

wherein each of said plurality of cymbal-shaped acoustic elements is disposed in a mechanical parallel arrangement between said pair of plates, and each of said cymbal-shaped elements is further disposed in electric parallel arrangement with respect to one another,

whereby when said electro-acoustic transducer is driven in a piston mode said plates experience an up and down motion in a linear fashion, resulting in a near field velocity that is substantially linear.

5. The transducer of claim 4, wherein said each of said plurality of cymbal-shaped acoustic elements is a stack of cymbal-shaped acoustic elements disposed in mechanical series arrangements with one another.

6. The transducer of claim 4, wherein said transducer comprises a water tight sealant surrounding said plates.