High-performance electroactive polymer transducers

• US 20060208610A1
• Filed: 03/21/2005
• Published: 09/21/2006
• 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, Jon
• Granted Patent: US 7,521,840 B2
• Time in Patent Office: Days
• US Class Current: 310/311
• 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. An electroactive polymer transducer comprising:

an open frame,

electroactive polymer material, and

a cap affixed to the polymer material,

wherein the cap less flexible than adjacent polymer material so the cap provides a stable interface portion of the transducer, and

wherein the polymer material stretched into a concave shape with the cap.

2. The transducer of claim 1, wherein the cap is bonded to the polymer material.

3. The transducer of claim 1, wherein the cap is mechanically affixed to the polymer material.

4. The transducer of claim 1, wherein a pair of caps are attached on each side of the polymer material opposite to each other.

5. The transducer of claim 4, wherein the polymer material and at least one of the caps is imperforate.

6. The transducer of claim 1, wherein the cap has an interior open section.

7. The transducer of claim 1, wherein the transducer is an actuator and the cap is adapted to move in a direction that increases and decreases a depth of the concave shape.

8. The transducer of claim 7, wherein the cap is planar and the transducer is adapted to move the cap in a direction perpendicular to a face of the cap.

9. The transducer of claim 1, wherein the transducer is adapted to operate as a sensor.

10. The transducer of claim 1, wherein the transducer is adapted to operate as an actuator.

11. The transducer of claim 1, wherein the transducer is adapted to operate as a sensor and an actuator.

12. The transducer of claim 1, wherein a fastener is attached to the cap.

13. The transducer of claim 1, wherein the cap comprises a portion of a valve.

14. The transducer of claim 1, wherein the cap carries a lens.

15. The transducer of claim 1, wherein the polymer material and cap form a section in the shape of a frustum.

16. The transducer of claim 15, wherein only one frustum section is provided.

17. The transducer of claim 16, wherein a spring biases the cap.

18. The transducer of claim 15, wherein two frustum sections are provided, and wherein each one biases the other.

19. The transducer of claim 18, wherein the frustum sections face opposite one another.

20. The transducer of claim 19, wherein each frustum has a cap and the caps are secured to one another.

21. The transducer of claim 20, wherein the frustum sections face towards one another.

22. The transducer of claim 21, wherein each frustum section has a cap and a spacer is provided between the caps.

23. The transducer of claim 1, wherein a cross-section of the polymer material is round in shape.

24. The transducer of claim 23, wherein the round cross-section is circular.

25. The transducer of claim 1, wherein a cross-section of the polymer material is rectilinear in shape.

26. The transducer of claim 25, wherein the rectilinear cross-section is substantially square.

27. The transducer of claim 1, wherein the polymer material comprises a plurality of independently addressed sections.

28. The transducer of claim 27, wherein the polymer material comprises two concave sections facing opposite one another.

29. The transducer of claim 27, where the transducer can alternatively be set to a configuration with two spaced apart substantially planer polymer material sections and be actuated in a direction substantially parallel to the substantially planar material.

30. The transducer of claim 29, wherein a rod slidingly received by the frame is actuated on an axis parallel to the substantially planar material.

31. An electroactive polymer transducer comprising:

an open frame,

two sections of electroactive polymer material, the polymer material stretched and held by the frame,

wherein the device is adapted to be configured with the sections of polymer material alternatively held in concave shapes or substantially parallel.

32. The transducer of claim 31, wherein the sections of polymer material are configured in concave shapes facing toward one another with a spacer therebetween.

33. The transducer of claim 31, wherein each section of polymer material has a cap.

34. The transducer of claim 31, wherein sections of polymer material are configured in concave shapes facing away from one another.

35. The transducer of claim 31, wherein the sections of polymer material are configured substantially flat with a spacer therebetween and a rod is attached to the spacer.

36. A transducer assembly, the assembly comprising a plurality of concave transducer sections comprising electroactive polymer material, wherein the sections are stacked in opposite facing directions upon one another.

37. The assembly of claim 36, wherein the transducers are as described by claim

38. The assembly of claim 37, wherein caps attached opposite facing transducer sections.

39. An electroactive polymer transducer comprising:

an open frame and electroactive polymer material,

wherein the polymer material is stretched into a frustum shape.

40. The transducer of claim 39, wherein the frustum has a cone angle when relaxed of between about 15 and about 85 degrees.

41. The transducer of claim 39, wherein the cone angle is between about 30 and about 60 degrees.

42. The transducer of claim 39, wherein the frustum shape is produced by tension applied around a perimeter of the polymer material.

43. The transducer of claim 42, wherein opposite-facing frustum shapes are provided and wherein a face of each frustum shape is attached to the other.

44. The transducer of claim 43, wherein the faces are bonded together.

45. The transducer of claim 43, wherein the faces are bonded to a common cap.

46. The transducer of claim 43, wherein the faces are each bonded to a separate cap.

47. The transducer of claim 46, where in caps are mechanically attached to one another.

48. The transducer of claim 43, wherein the faces are captured between separate caps mechanically attached to one another.

49. A transducer system comprising:

a open three-dimensional frame, and electroactive polymer material stretched within the frame to define each of at least one diaphragm transducer and at least one of a planar transducer.

50. The system of claim 49, wherein one diaphragm transducer is provided to control focus and a pair of planar transducers are provided to control zoom in a camera.