Patent EA-004494-B1 (EA)
Title: Conductive pressure sensitive texture
Inventor: SWALLOW STANLEY SHIGEZO
IPC: G06F3/033
Filed: 2001-04-02
Abstract: 1. A pressure sensitive fabric provided with a single layer including warp and weft filaments within said single layer, wherein the warp filaments include at least one first elongated electrical conductor and the weft filaments include at least one second elongated electrical conductor, said first conductor or conductors being crossed by said second conductor or conductors, said conductors being normally biased apart at a crossover point of said conductors with an air gap between them resulting from insulating fibres or filaments which bias the first and second conductors apart at the crossover point, whereby application of pressure in a direction substantially normal to a plane of the fabric causes the conductors to make contact. 2. A fabric according to claim 1, including a plurality of spaced first conductors and/or a plurality of spaced second conductors, forming a plurality of said crossover points. 3. A fabric according to claim 1 or 2, wherein each conductor comprises electrically conductive filaments or fibres. 4. A fabric according to any one of claims 1 to 3, which is woven, knitted, non-woven or plaited. 5. A fabric according to any one of claims 1 to 4, wherein said biasing apart is effected by locating an electrical conductor of relatively smaller cross-section between insulating filaments or fibres of relatively larger cross-section. 6. A fabric according to any one of claims 1 to 4, wherein the weave includes warp and/or weft floats over more than one yarn to effect the biasing apart of first and second electrical conductors at the crossover point. 7. A fabric according to any one of claims 1 to 4, wherein said biasing apart is effected by employing, as at least one of the electrical conductors, an electrical conductor including insulating filament or fibre wound around it to leave the surface of the conductor exposed at the crossover point. 8. A fabric according to any one of claims 1 to 4, wherein said biasing apart is effected by twisting at least one of the electrical conductors together with insulating filament or fibre. 9. A fabric according to any one of claims 1 to 4, wherein said biasing apart is effected by employing, as at least one of the electrical conductors, an electrical conductor which is supported on and between deformable protuberances of an insulating filament or fibre. 10. A fabric according to any one of claims 1 to 4, wherein said biasing apart is effected by employing, as at least one of the electrical conductors, a fibre including an insulating yarn and a conductive yarn, the insulating yam including portions extending beyond the conductive yarn. 11. A fabric according to claim 10, wherein there are provided two or more conductive yarns helically wound around the insulating yarn. 12. A fabric according to any preceding claim, wherein the electrical conductors have an electrical property which is proportional to the length of the conductor, whereby the length of a conductor or plurality of connecting conductors can be determined from measurement of that property. 13. A fabric according to claim 12, wherein the electrical property is electrical resistance. 14. A fabric according to any preceding claim, including at least one set of spaced electrical conductors, at least some of said set being electrically connected together to form at least one bus bar. 15. A fabric according to claim 14, wherein said set of spaced electrical conductors comprises electrically conductive filaments or fibres in the warp or weft of a woven construction and electrical connection between conductors of that set is provided by one or more electrically conducting filaments or fibres in the weft or warp, respectively. 16. A fabric according to claim 14, wherein set of spaced electrical conductors comprises electrically conductive filaments or fibres in the warp or weft of a woven construction and said electrical connection is effected after the weaving process.