Pressure responsive sensor

• US 20070084293A1
• Filed: 10/16/2006
• Published: 04/19/2007
• Est. Priority Date: 10/14/2005
• Status: Active Grant

• Current Assignee: T-Ink Inc. (Winnick & Co., Inc.)
• Original Assignee: Ink-Logix
• Inventors: Gentile, John, Kaiserman, Terrance, Bravo, Juan, Margolin, Keith, Yung, Vitus
• Granted Patent: US 7,594,442 B2
• Time in Patent Office: Days
• US Class Current: 73/763
• CPC Class Codes: B60N 2/002 Seats provided with an occupancy detection means mounted therein or thereon detection means responsive to presence or absence of children B60N2/266
• CPC Class Codes: G01L 1/20 by measuring variations in ohmic resistance of solid materials or of electrically-conductive fluids of piezo-resistive materials G01L1/18; by making use of electrokinetic cells, i.e. liquid-containing cells wherein an electrical potential is produced or varied upon the application of stress

Abstract

In accordance with one embodiment, a sensor includes a fibrous region contacting at least two electrodes. The fibrous region has an electrically conductive coating. The fibrous region has a resistance and when the fibrous region is compressed, the resistance changes. In another embodiment, a method of making a pressure responsive sensor includes providing a compressible material, applying a conductive coating to the compressible material to provide a coated compressible material having a resistance, and placing the coated compressible material in contact with at least two electrodes, wherein when the compressible material is compressed, the resistance changes.

Claims

1. A sensor comprising:

a fibrous region contacting at least two electrodes, said fibrous region having an electrically conductive coating, wherein the fibrous region has a resistance and when the fibrous region is compressed, the resistance changes.

2. The sensor of claim 1, wherein said at least two electrodes are printed upon at least one substrate.

3. The sensor of claim 2, wherein said at least one substrate is flexible.

4. The sensor of claim 2, wherein said substrate is selected from the group consisting of a woven fabric, a non-woven fabric, a mesh, a sheet, and a plastic.

5. The sensor of claim 1, wherein said coating comprises a resin having an electrically conductive material dispersed therein, and the resin electrically conductive material adheres to said fibrous region.

6. The sensor of claim 1, wherein the fibrous region comprises a fiberfill.

7. The sensor of claim 6, wherein the fiberfill has a compressed volume and an uncompressed volume, and the ratio of the uncompressed volume to the compressed volume is at least about 1.5:

1.

8. The sensor of claim 7, wherein the ratio of the uncompressed volume to the compressed volume is at least about 5:

1.

9. The sensor of claim 1, wherein said changes in the electrical resistance of said fibrous region indicate the magnitude of said compression.

10. The sensor of claim 1, wherein said two electrodes are located on the same surface.

11. The sensor of claim 1, wherein said two electrodes do not overlap in plan view.

12. The sensor of claim 1, wherein said two electrodes are located opposite one another.

13. The sensor of claim 1, further comprising a resilient non-conductive region partially surrounding said fibrous region.

14. The sensor of claim 13, wherein said resilient non-conductive region is selected to provide a predetermined relationship between an applied compressive force and the amount of compression of said fibrous region.

15. A vehicle seat, comprising the sensor of claim 1.

16. The sensor of claim 1, further comprising a pouch that contains said fibrous region.

17. The sensor of claim 1, wherein said fibrous region is at least partially protected by a moisture-resistant covering.

18. A comforter comprising at least one pressure sensor of claim 1.

19. A sensor comprising:

a compressible material having a resistance;

two electrodes, wherein compression of said compressible material causes the resistance of said compressible material to increase; and

wherein said electrodes are in electrical communication with said compressible material when the compressible material is compressed.

20. The sensor of claim 19, wherein said compressible material is a foam.

21. The sensor of claim 20, wherein said foam is selected from the group consisting of an open-cell foam and a closed-cell foam.

22. The sensor of claim 20, wherein said foam is surface-coated with a conductive material.

23. The sensor of claim 19, wherein said electrodes are on the same surface of a substrate.

24. The sensor of claim 23, wherein said electrodes are printed on said substrate.

25. The sensor of claim 19, further comprising:

a button retaining said compressible material and selected to provide a predetermined relationship between an applied compressive force and the amount of compression of said compressible material.

26. The sensor of claim 19, further comprising:

a button, wherein when a compressive force is applied to the button, the button compresses the compressible material;

an illumination source; and

a light guide guiding light from said illumination source.

27. The sensor of claim 19, wherein said compressible material is at least partially covered by a moisture-resistant material.

28. A sensor comprising:

a compressible material having a resistance; and

two electrodes printed on a substrate, wherein when the compressible material is compressed, the resistance of the compressible material changes, and such that said electrodes are in electrical communication with said compressible material.

29. The sensor of claim 28, wherein said compressible material is inherently conductive.

30. The sensor of claim 28, wherein said compressible material is a fiberfill comprising a conductive coating.

31. The sensor of claim 28, wherein said compressible material is low density foam comprising a conductive coating throughout.

32. The sensor of claim 28, further comprising:

a button retaining said compressible material and selected to provide a predetermined relationship between an applied compressive force and the amount of compression of said compressible material.

33. The sensor of claim 28, further comprising:

a button, wherein when a compressive force is applied to the button, the button compresses the compressible material;

a light source; and

a light guide guiding the light from said light source.

34. A method of making a pressure responsive sensor comprising:

providing a compressible material;

applying a conductive coating to the compressible material to provide a coated compressible material having a resistance; and

placing the coated compressible material in contact with at least two electrodes, wherein when the compressible material is compressed, the resistance changes.

35. The method of claim 34, wherein said electrodes are located in a non-opposing manner with relation to said compressible material.

36. The method of claim 34, wherein said compressible material comprises one selected from a foam and a fiberfill.

37. The method of claim 34, wherein the step of applying a conductive coating comprises one selected from dipping the compressible material in the coating and spraying the conductive coating on the material.

38. The method of claim 34, wherein when the compressible material is compressed, the resistance increases.

39. The method of claim 34, further comprising printing the two electrodes on a substrate.

40. The method of claim 34, further comprising providing a cushion formed with an internal space, and inserting the coated compressible material within said internal space.

41. The method of claim 40, wherein said cushion has first and second faces, said space being open to the first and second faces, the method further comprising covering the cushion with an electrically nonconductive cover having at least one electrically conductive trace on a portion thereof, wherein the at least one electrically conductive trace faces into the space.

42. The method of claim 34, further comprising electrically connecting an electrical circuit said coated compressible material such that the electrical circuit senses the resistance of the coated compressible material.

43. The method of claim 42, wherein said electrical circuit generates a signal representative of the resistance of the coated compressible material.

44. The method of claim 43, where said electrical circuit further comprises a transmitter for wirelessly transmitting a representation of said signal.

45. The method of claim 40, wherein the material of the cushion is selected to provide a predetermined relationship between an applied compressive force and the amount of compression of the cushion.

46. The method of claim 34, further comprising at least partially covering the coated compressible material with a moisture resistant material.