Flexible switching devices

• US 7,145,432 B2
• Filed: 05/17/2001
• Issued: 12/05/2006
• Est. Priority Date: 05/18/2000
• Status: Expired due to Term

• Current Assignee: Peratech Limited
• Original Assignee: Canesis Network Limited (Agresearch Limited), Peratech Limited
• Inventors: Jones, Dianne, Leftly, Steven, Lussey, David
• Primary Examiner(s): Hoang, Tu
• Application Number:
  US10/276,220
• Publication Number:
  US 20040252007A1
• Time in Patent Office: 2,028 Days
• Field of Search: 338/47, 338/99, 338/101, 338/114, 219/529, 219/545, 358/22.R, 345/178, 235/462.44
• US Class Current: 338/47
• CPC Class Codes: H01H 1/021 Composite material
• CPC Class Codes: H01H 2201/036 Variable resistance
• CPC Class Codes: H01H 3/141 Cushion or mat switches
• CPC Class Codes: Y10T 428/254 Polymeric or resinous material

Abstract

An electronic resistor user interface comprises flexible conductive materials and a flexible variably resistive element capable of exhibiting a change in electrical resistance on mechanical deformation and is characterised by textile-form electrodes (10,12) a textile form variably resistive element (14) and textile-form members (16) connective to external circuitry.

Claims

1. A variable resistance user-interface comprising:

textile-form flexible conductive electrodes connective to associated circuitry; and

a textile-form variably resistive element comprising a plurality of fibers and capable of exhibiting a change in electrical resistance on mechanical deformation, the textile-form variably resistive element being formed as a coating applied to said fibers continuously along the fibers'"'"' lengths, said textile-form variably resistive element being sandwiched between the electrodes.

2. A user-interface according to claim 1 in which at least one electrode is supported on non-conducting textile as conductive yarn woven, knitted or embroidered into the non-conducting textile.

3. A user-interface according to claim 1 in which at least one electrode is formed by applying a conductive printing ink to the support textile.

4. A user-interface according to claim 1 in which the variably resistive element consists of particulate variably resistive material and an elastomer binder.

5. A user-interface according to claim 4 in which the variably resistive material is a polymer composition in which a filler selected from powder-form metallic elements or alloys, electrically conductive oxides of said elements and alloys, and mixtures thereof are in admixture with a non-conductive elastomer, having been mixed in a controlled manner whereby the filler is dispersed within the elastomer and remains structurally intact and voids present in a starting filler powder become infilled with elastomer during curing of the elastomer.

6. A user-interface according to claim 1 in which the electrodes are connected to textile-form members, the textile-form members being connective to associated circuitry and wherein the textile-form members being constituted by conductive material present as conductive tracks in or on at least one of a textile support, a ribbon and a tape.

7. A user-interface as claimed in claim 6 in which the conductive tracks are at least one of woven, knitted, sewn, embroidered and printed.

8. A user-interface according to claim 1 in which at least one of the electrodes comprises variably resistive material pre-stressed to conductance.

9. A user-interface according to claim 1 in which at least one electrode is supported on non-conducting textile as conductive fabric sewn or bonded onto the non-conducting textile.

10. A user-interface according to claim 1 in which at least one electrode is supported on non-conducting textile as conductive coating applied to the non-conducting textile.

11. A user-interface according to claim 1 in which the textile form variably resistive element is fixed in intimate contact with each of the textile form electrodes.

12. A user-interface according to claim 1 in which the variably resistive element consists of particulate conducting polymer material and an elastomer binder.

13. A user-interface according to claim 12 in which the conducting polymer is one of the group consisting of polyaniline, polypyrrole and polythiophenes.

14. A user-interface according to claim 1 in which the variably resistive element consists of particulate carbon material and an elastomer binder.

15. A user interface according to claim 1 in which the electrodes are connected to textile-form members, the textile-form members being connective to associated circuitry and at least one of the textile-form members comprises variably resistive material pre-stressed to conductance.

16. A user-interface according to claim 1 further comprising at least one support textile having a sub-area;

and at least one of said textile-form flexible conductive electrodes comprises a conductive textile-form member associated with the sub-area, said conductive textile-form member being connective to the associated circuitry.

17. A user-interface according to claim 16 wherein the conductive textile-form member comprises a terminal at which the conductive textile-form member passes electric current to the associated circuitry.

18. A variable resistance user-interface comprising:

textile-form flexible conductive electrodes connective to associated circuitry; and

a textile-form variably resistive element comprising a plurality of fibers and capable of exhibiting a change in electrical resistance on mechanical deformation, the textile-form variable resistive element being formed as a variably resistive coating applied to said fibers continuously along the fibers'"'"' lengths, said textile form variably resistive element being sandwiched between the electrodes.