SURFACE DEFORMATION ELECTROACTIVE POLYMER TRANSDUCERS

• US 20100109486A1
• Filed: 01/22/2009
• Published: 05/06/2010
• Est. Priority Date: 11/05/2008
• Status: Active Grant

• Current Assignee: Bayer Materialscience AG (Covestro AG)
• Original Assignee: Artificial Muscle, Inc. (Covestro AG)
• Inventors: WEABER, Chris A., POLYAKOV, Ilya
• Granted Patent: US 8,222,799 B2
• Time in Patent Office: Days
• US Class Current: 310/365
• CPC Class Codes: G06F 3/0202 Constructional details or processes of manufacture of the input device
• CPC Class Codes: G06F 3/044 by capacitive means
• CPC Class Codes: H10N 30/06 Forming electrodes or interconnections, e.g. leads or terminals
• CPC Class Codes: H10N 30/063 Forming interconnections, e.g. connection electrodes of multilayered piezoelectric or electrostrictive parts
• CPC Class Codes: H10N 30/098 Forming organic materials
• CPC Class Codes: H10N 30/206 using only longitudinal or thickness displacement, e.g. d33 or d31 type devices
• CPC Class Codes: H10N 30/857 Macromolecular compositions
• CPC Class Codes: H10N 30/874 embedded within piezoelectric or electrostrictive material, e.g. via connections
• CPC Class Codes: H10N 30/875 Further connection or lead arrangements, e.g. flexible wiring boards, terminal pins
• CPC Class Codes: Y10S 310/80 Piezoelectric polymers, e.g. PVDF
• CPC Class Codes: Y10T 29/42 Piezoelectric device making

Abstract

Electroactive polymer transducers configured for surface mode deformation to provide thickness mode actuation.

Claims

1. A transducer comprising:

an electroactive polymer film comprising a thin dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is sandwiched between first and second electrodes wherein the overlapping portions of the electrodes define an active film region with the remaining portion of film defining an inactive film region;

a first conductive layer disposed on at least a portion of the inactive film region and electrically coupled to the first electrode, and a second conductive layer disposed on at least a portion of the inactive film region and electrically coupled to the second electrode; and

at least one passive polymer layer, the polymer layer extending over at least a portion of one side of the electroactive polymer film, wherein activation of the active region changes a thickness dimension of the passive polymer layer.

2. The transducer of claim 1 further comprising a first conductive via extending through the transducer at a location which includes the first electrode and a second conductive via extending through the transducer at a location which includes the second electrode.

3. The transducer of claim 1 further comprising at least one rigid output structure mounted to a passive polymer layer.

4. The transducer of claim 3 further comprising a rigid output structure mounted to each passive polymer layer.

5. The transducer of claim 1 comprising two passive polymer layers, one on each side of the electroactive polymer film.

6. The transducer of claim 1, wherein the transducer is used to provide haptic feedback.

7. The transducer of claim 6 wherein the haptic feedback is provided for a touch screen device, a touch panel, a button, a key or a pointing device.

8. The transducer of claim 1, wherein the transducer controls the opening and closing of a valve mechanism.

9. The transducer of claim 1, wherein the transducer controls the flow of fluid through a chamber.

10. The transducer of claim 1, wherein the transducer controls a linear braking system.

11. The transducer of claim 1, wherein the transducer controls a rotary braking system.

12. The transducer of claim 1, wherein the active region is central to the inactive region.

13. The transducer of claim 12, wherein the passive layer extends over the active and the inactive regions.

14. The transducer of claim 12, wherein the transducer is used to provide haptic feedback.

15. The transducer of claim 1, wherein the inactive region is central to the active region.

16. The transducer of claim 12, wherein the transducer is used to provide haptic feedback.

17. The transducer of claim 15, wherein the passive layer extends over only the inactive region.

43. A user interface device providing haptic feedback comprising:

an array of transducers of claim 17; and

at least one user contact surface positioned over the array of transducers.

44. The user interface device of claim 43, wherein the user interface device is a keypad or keyboard.

18. A transducer assembly comprising;

at least two stacked layers of electroactive polymer film, each electroactive polymer film comprising a thin dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is sandwiched between first and second electrodes wherein the overlapping portions of the electrodes define an active film region with the remaining portion of film defining an inactive film region, wherein the active film regions of the respective layers of electroactive polymer film are in stacked alignment and the inactive active film regions of the respective layers of electroactive polymer film are in stacked alignment; and

a first conductive layer disposed on at least a portion of the inactive film region of each electroactive polymer film and electrically coupled to tile first electrode thereof, and a second conductive layer disposed on at least a portion of the inactive film region of each electroactive polymer film and electrically coupled to the second electrode thereof.

19. The transducer assembly of claim 18 further comprising a passive polymer layer over each exposed side of the electroactive polymer films, wherein activation of the active regions changes a thickness dimension of the passive polymer layers.

20. The transducer assembly of claim 18 further comprising a first conductive via extending through the stacked electroactive polymer films at a location which includes the first electrode of each film and a second conductive via extending through the stacked electroactive polymer films at a location which includes the second electrodes.

21. A method of fabricating a transducer comprising:

providing a transducer comprising;

an electroactive polymer film comprising a thin dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is sandwiched between first and second electrodes wherein the overlapping portions of the electrodes define an active film region with the remaining portion of film defining an inactive film region;

a first conductive layer disposed on at least a portion of the inactive film region and electrically coupled to the first electrode, and a second conductive layer disposed on at least a portion of the inactive film region and electrically coupled to the second electrode; and

at least one passive polymer layer, the polymer layer extending over at least a portion of one side of the electroactive polymer film, wherein activation of the active region changes a thickness dimension of the passive polymer layer; and

forming first and second vias through the electroactive transducer at locations comprising first and second conductive layers, respectively, wherein the vias are drilled to a depth at least to the conductive layers; and

filling the vias with a conductive material, wherein the vias are electrically coupled to a source of power.

22. The method of claim 21 further comprising potting the filled vias with a non-conductive material.

23. The method of claim 21 further comprising placing a non-conductive tape over the filled vias.

24. The method of claim 21 further comprising mounting the transducer to electrical traces coupled to a source of power, wherein the vias are drilled through the entire thickness of the transducer.

25. The method of claim 21 further comprising inserting conductive leads into the conductive material.

26. The method of claim 21, wherein forming the vias comprises drilling, punching, molding, piercing, or coring the electroactive transducer.

27. A method of fabricating a transducer comprising:

providing a transducer comprising;

an electroactive polymer film comprising a thin dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is sandwiched between first and second electrodes wherein the overlapping portions of the electrodes define an active film region with the remaining portion of film defining an inactive film region;

a first conductive layer disposed on at least a portion of the inactive film region and electrically coupled to the first electrode, and a second conductive layer disposed on at least a portion of the inactive film region and electrically coupled to the second electrode; and

at least one passive polymer layer, the polymer layer extending over one side of the electroactive polymer film, wherein activation of the active region changes a thickness dimension of the passive polymer layer; and

driving first and second conductive contacts having a piercing configuration through the transducer at locations comprising first and second conductive layers, respectively, to a depth that penetrates the conductive layers.

28. The method of claim 27 further comprising mounting the transducer to electrical traces coupled to a source of power, wherein exposed ends of the conductive contacts are electrically coupled to the source of power.

29. A transducer comprising:

an electroactive polymer film comprising a thin dielectric elastomer layer, wherein a portion of the dielectric elastomer layer is sandwiched between first and second electrodes, wherein each of the electrodes comprises symmetrical trace patterns apposing each other, wherein the areas of electrode apposition are active and the remaining areas are inactive, wherein activation of the active areas increases a thickness dimension of the inactive areas.

30. The transducer of claim 29, wherein the respective trace patterns comprises a plurality of substantially parallel, spaced apart traces.

31. The transducer of claim 30, wherein the plurality of traces form a concentric pattern.

32. The transducer of claim 31, wherein the electrode patterns are sized for use in a button actuator.

33. The transducer of claim 29, wherein the plurality of traces form a novelty shape.

34. The transducer of claim 29, wherein the transducer has a strip configuration.

35. The transducer of claim 34, wherein the transducer strip is singulated from a continuous strip of electroactive polymer film.

36. The transducer of claim 35, wherein the electrode patterns are continuous along the strip.

37. The transducer of claim 35, wherein the electrode patterns are discrete and repeating along the strip.

38. The transducer of claim 34, wherein the transducer strip frames an open space.

39. The transducer of claim 38, wherein the transducer forms a gasket-type actuator.

40. The transducer of claim 39, wherein the gasket-type actuator is used for actuating a touch screen device.

41. A user interface device providing haptic feedback comprising:

an array of transducers of claim 32; and

at least one user contact surface positioned over the array of transducers.

42. The user interface device of claim 41, wherein the user interface device is a keypad or keyboard.