High-performance electroactive polymer transducers

• US 7,923,902 B2
• Filed: 03/13/2009
• Issued: 04/12/2011
• Est. Priority Date: 03/21/2005
• Status: Active Grant

• Current Assignee: Bayer Materialscience AG (Covestro AG)
• Original Assignee: Bayer Materialscience AG (Covestro AG)
• Inventors: Heim, Jonathan R.
• Primary Examiner(s): Dougherty; Thomas M
• Assistant Examiner(s): ADDISON, KAREN B
• Application Number:
  US12/404,237
• Publication Number:
  US 20090174293A1
• Time in Patent Office: 760 Days
• Field of Search: 310/309, 310/328, 310/330, 310/800, 310/329, 381/129, 381/174
• US Class Current: 310/328
• CPC Class Codes: F04B 43/0054 particularities of the flexible members
• CPC Class Codes: F04B 43/04 Pumps having electric drive
• CPC Class Codes: G02B 13/009 having zoom function
• CPC Class Codes: G02B 7/102 controlled by a microcomputer cameras with interchangeable lenses G03B17/14
• CPC Class Codes: H04R 19/02 Loudspeakers H04R19/01 takes precedence
• 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

Electroactive polymer constructions that convert electrical energy to mechanical energy and vice versa are disclosed. The subject transducers (actuators, generators, sensors or combinations thereof) share the requirement of a frame or fixture element used in preloading elastomeric film electrodes and dielectric polymer in a desired configuration. The structures are either integrally biased in a push-pull arrangement or preloaded/biased by another element.

Claims

1. A device comprising:

an open frame; and

electroactive elastomer material secured within the frame and a region central to the elastomer material which form a diaphragm;

wherein the central region is less flexible than the elastomer material and wherein the elastomer material is stretched to a concave or convex shape and wherein the central region comprises a substantially rigid cap coupled to the frame by a spring.

2. The device of claim 1, wherein the spring is a selected from a leaf spring and a coil spring.

3. The device of claim 1, wherein-the spring biases the electroactive elastomer material out of plane into the concave or convex shape.

4. The device of claim 1, wherein the diaphragm forms a frustum structure.

5. The device of claim 1, wherein the central region is imperforate.

6. The device of claim 1, wherein the central region has an interior open section.

7. The device of claim 1, wherein device is adapted to operate as a sensor.

8. The device of claim 1, wherein device is adapted to operate as an actuator.

9. The device of claim 1, comprising at least two diaphragms wherein each of the at least two elastomeric material sections are stretched into frustum shapes.

10. The device of claim 9, wherein one diaphragm biases another diaphragm.

11. The device of claim 9, wherein the frustum sections face opposite one another.

12. The device of claim 9, wherein the frustum sections face towards one another.

13. The device of claim 9, wherein the central regions are ganged together.

14. The device of claim 1, wherein the elastomeric material comprises a plurality of independently addressed sections.

15. An assembly comprising a plurality of stacked diaphragms according to claim 1.

16. The device of claim 15, wherein the stacked diaphragms are connected in series.

17. The device of claim 15, wherein the stacked diaphragms are connected in parallel.

18. The device of claim 15, wherein a portion of the stacked diaphragms faces in one direction and another portion of the stacked diaphragms faces in an opposite direction.

19. The device of claim 1, where upon application of a voltage across the electroactive elastomer alters the concave or convex shape.