High-performance electroactive polymer transducers

• US 7,679,267 B2
• Filed: 04/20/2009
• Issued: 03/16/2010
• Est. Priority Date: 03/21/2005
• Status: Active Grant

• Current Assignee: Bayer Materialscience AG (Covestro AG)
• Original Assignee: Artificial Muscle, Inc. (Covestro AG)
• Inventors: Heim, Jonathan R.
• Primary Examiner(s): Benson; Walter
• Assistant Examiner(s): Gordon; Bryan P
• Application Number:
  US12/426,856
• Publication Number:
  US 20090236939A1
• Time in Patent Office: 330 Days
• Field of Search: 310/800, 310/328, 310/324
• US Class Current: 310/324
• CPC Class Codes: F04B 43/0054 particularities of the flexible members
• CPC Class Codes: F04B 43/04 Pumps having electric drive
• CPC Class Codes: F04B 43/14 having plate-like flexible members
• CPC Class Codes: H02N 2/046 for conversion into rotary motion
• CPC Class Codes: H04R 17/025 using a piezoelectric polymer
• CPC Class Codes: H10N 30/206 using only longitudinal or thickness displacement, e.g. d33 or d31 type devices
• CPC Class Codes: Y10S 310/80 Piezoelectric polymers, e.g. PVDF

Abstract

A transducer employing at least two electroactive polymer layers stretched to join each central portion of the electroactive polymer layers to each form a concave shape wherein the central portions of the electroactive polymer layers actuate in at least two component directions upon application of a voltage across the electroactive polymer material.

Claims

1. A transducer comprising:

a frame structure defining an opening and at least two electroactive polymer layers extending within the opening of the frame, the electroactive polymer layers each having an elastic modulus below about 100 MPa and a central portion, wherein the electroactive polymer layers are stretched to join at each central portion of the electroactive polymer layers to each form a concave shape;

wherein the central portions of the electroactive polymer layers actuate in at least two component directions upon application of a voltage across the electroactive polymer material.

2. The transducer of claim 1 further comprising a mass coupled to at least one of the electroactive polymer layers to tune the electroactive polymer layers for high frequency operations at or near about their natural resonance.

3. The transducer of claim 2, wherein the mass includes a spacer, a cap, or a spacer and cap combination.

4. The transducer of claim 1, wherein the electroactive polymer layers have a clocked output frequency of about 50 Hz, 100 Hz, or 1 KHz.

5. The transducer of claim 1, wherein the electroactive polymer layers form a double-frustum configuration.

6. The transducer of claim 1, wherein the coupled-together portions define a cap structure.

7. The transducer of claim 6, wherein the cap structure has a disc-like configuration and at least one pass-through hole.

8. The transducer of claim 1, wherein the electroactive polymer material comprises silicone.

9. The transducer of claim 1, wherein the electroactive polymer material comprises acrylic.

10. The transducer of claim 1, wherein the electroactive polymer material comprises a dielectric elastomer.

11. The transducer of claim 1, wherein output motion of the electroactive polymer layers has a frequency within a range from about 0.1 Hz to about 1 KHz.

12. A transducer comprising:

an open frame and at least two diaphragm layers, each diaphragm layer comprising an electroactive polymer material having an elastic modulus below about 100 MPa and extending within the frame, the electroactive polymer material being tuned for high frequency operations at or near about their natural resonance, wherein central portions of the diaphragm layers are coupled together and remaining portions of one diaphragm layer are spaced from remaining portions of the other diaphragm layer, and wherein the diaphragm layers are free to actuate in at least two component directions upon application of a voltage across the electroactive polymer material.

13. The transducer of claim 12, wherein the high frequency of operation is tuned at or near about natural resonance of the diaphragm layers.

14. The transducer of claim 12, wherein the diaphragm layers form a double-frustum configuration.

15. The transducer of claim 12, wherein the coupled-together central portions define a cap structure.

16. The transducer of claim 15, wherein the cap structure has a disc configuration having at least one pass-through hole therethrough.

17. The transducer of claim 12, wherein the electroactive polymer material comprises silicone.

18. The transducer of claim 12, wherein the electroactive polymer material comprises acrylic.

19. The transducer of claim 12, wherein the electroactive polymer material comprises a dielectric elastomer.

20. The transducer of claim 12, wherein output motion of the diaphragm layers has a frequency with the range from about 0.1 Hz to about 1 kHz.