Electrically conductive yarn

Abstract

An electrically conductive yarn (200, 300) comprising a first yarn (262, 362) and a second yarn (264, 364), the first yarn (262, 362) comprises or consists out of a plurality of stainless steel fibers, the second yarn (264, 364) comprises organic fibers wherein the first yarn (362) and the second yarn (364) are twisted or cabled together or the second yarn (264) is wrapped around the first yarn (262) such that the first yarn (262) is provided as a core yarn and such that the first yarn (262) provides part of the surface of the electrically conductive yarn (200).

Claims

1. A pneumatic rubber tire for a motorized vehicle, comprising a bead portion, wherein the bead portion comprises steel wire bead reinforcement and a rubber component comprising electrically conductive particles, a carcass portion comprising a rubber component and carcass reinforcement plies comprising high tenacity polymer fiber cords, a tread portion comprising a rubber component comprising electrically conductive particles, and at least one electrically conductive yarn, wherein the at least one electrically conductive yarn is embedded in rubber, and wherein the at least one electrically conductive yarn extends from the bead portion of the tire, through the carcass portion, to the tread portion of the tire, wherein the electrically conductive yarn comprises: a first yarn, wherein the first yarn comprises a plurality of stainless steel fibers, and a second yarn, wherein the second yarn comprises organic fibers, wherein either 1) the first yarn and the second yarn are twisted or cabled together with a twist of more than 20 turns per meter, or 2) the second yarn is wrapped around the first yarn such that the first yarn is provided as a core yarn and such that the first yarn provides part of the surface of the electrically conductive yarn.

2. The pneumatic rubber tire according to claim 1, wherein the at least one electrically conductive yarn is positioned on the outer surface of a carcass reinforcement ply between the carcass reinforcement plies and the sidewall rubber layer, or on the inner surface of a carcass reinforcement ply between the carcass reinforcement plies and the tire rubber inner liner layer, or between two carcass reinforcement plies.

3. The pneumatic rubber tire according to claim 1, wherein the organic fibers are thermoplastic polymer fibers selected from the group consisting of polyester fibers, polyamide fibers, and para-aramid fibers.

4. The pneumatic rubber tire according to claim 1, wherein the organic fibers are cotton fibers, rayon fibers, or thermoplastic polymer fibers.

5. The pneumatic rubber tire according to claim 1, wherein the second yarn is a cotton fiber yarn.

6. The pneumatic rubber tire according to claim 1, wherein the plurality of stainless steel fibers are twisted and/or cabled together to form the first yarn.

7. The pneumatic rubber tire according to claim 1, wherein the stainless steel fibers have an equivalent diameter less than 30 μm.

8. The pneumatic rubber tire according to claim 1, wherein the stainless steel fibers are made via bundled drawing.

9. The pneumatic rubber tire according to claim 1, wherein the stainless steel fibers are filaments.

10. The pneumatic rubber tire according to claim 1, wherein the stainless steel fibers are fibers of discrete length.

11. The pneumatic rubber tire according to claim 1, wherein one or two second yarns is/are wrapped around the first yarn such that the first yarn is provided as a core yarn and such that the first yarn provides part of the surface of the electrically conductive yarn.

12. The pneumatic rubber tire according to claim 11, wherein the one or two second yarns is/are wrapped with less than 1000 turns per meter around the first yarn.

13. The pneumatic rubber tire according to claim 1, wherein the electrically conductive yarn comprises two second yarns, wherein one second yarn is wrapped in Z-direction around the first yarn, and wherein another second cotton yarn is wrapped in S-direction around the first yarn.

14. The pneumatic rubber tire according to claim 1, wherein the first yarn provides at least 10% of the surface of the electrically conductive yarn.

Description

BRIEF DESCRIPTION OF FIGURES IN THE DRAWINGS

(1) FIG. 1 shows a pneumatic rubber tire as in the second aspect of the invention.

(2) FIGS. 2, 3 and 5 show embodiments of electrically conductive yarns as in the first aspect of the invention.

(3) FIG. 4 shows a cross section of an electrically conductive yarn according to the first aspect of the invention.

MODE(S) FOR CARRYING OUT THE INVENTION

(4) FIG. 1 shows a cross section of a pneumatic rubber tire 100 as in the second aspect of the invention. The tire 100 comprises a bead portion 120, a carcass portion 130, a tread portion 140 and at least one electrically conductive yarn 170 as in the first aspect of the invention; e.g. as in the examples described in the following paragraphs. The bead portion 120 comprises steel wire bead reinforcement 124 and a rubber component 122 comprising electrically conductive particles. The carcass portion 130 comprises a rubber component 132 and carcass reinforcement plies 134 comprising high tenacity polymer fiber cords. The tread portion 140 comprises a rubber component 142 comprising electrically conductive particles and belt plies 144. The at least one electrically conductive yarn 170 is embedded in rubber; and extends from bead portion 120 of the tire, through the carcass portion 130, to the tread portion of the tire.

(5) FIG. 2 shows an example of an electrically conductive yarn 200 according to the first aspect of the invention. The electrically conductive yarn 200 comprises a first yarn 262 and one second yarn 264, e.g. a cotton yarn. The first yarn 262 consists out of a plurality of stainless steel fibers. The second yarn 264 is wrapped around the first yarn 262 such that the first yarn is provided as a core yarn; and such that the first yarn provides part of the surface of the electrically conductive yarn.

(6) FIG. 3 shows an example of an electrically conductive yarn 300 according to the first aspect of the invention. The electrically conductive yarn 300 comprises a first yarn 362 and two second yarns 364, e.g. cotton yarns. The first yarn 362 consists out of a plurality of stainless steel fibers. The second yarns 364 are wrapped around the first yarn 362 such that the first yarn is provided as a core yarn; and such that the first yarn provides part of the surface of the electrically conductive yarn. One second yarn is wrapped in S-direction and the other second yarn is wrapped in Z-direction around the first yarn. FIG. 4 shows a cross section 400 along A-A′ of the electrically conductive yarn of FIG. 3, it shows the first yarn 462 consisting out of bundled drawn stainless steel fibers 463 having a polygonal cross section; and the two second yarns 464.

(7) FIG. 5 shows an example of an electrically conductive yarn 500 according to the first aspect of the invention. The electrically conductive yarn 500 comprises a first yarn 562 and one second yarn 564, e.g. a cotton yarn. The first yarn 562 consists out of a plurality of stainless steel fibers. The first yarn 562 and the second yarn 564 are twisted together. Alternatively, the first yarn and the second yarn can be cabled together. The twist with which the first yarn and the second yarn are twisted or cabled together is preferably between 10 and 600 turns per meter length of the electrically conductive yarn.

(8) Besides cotton fiber yarns, other yarns can be used as second yarns; e.g. rayon fiber yarns, polyester fiber yarns, polyamide fiber yarns or para-aramid fiber yarns; or blended yarns comprising such fibers.

(9) An example of a first yarn that can be used in the invention is a twisted stainless steel filament yarn comprising 275 bundled drawn stainless steel filaments of equivalent diameter 12 μm, twisted with 100 turns per meter in Z-direction.

(10) Another example of a first yarn that can be used in the invention is a twisted stainless steel filament yarn comprising 550 bundled drawn stainless steel filaments of equivalent diameter 12 μm twisted together with 175 turns per meter in S-direction.

(11) Another example of a first yarn that can be used in the invention is a cabled stainless steel filament yarn comprising 2 times 275 bundled drawn stainless steel filaments of equivalent diameter 12 μm cabled together with 175 turns per meter.

(12) Another example of a first yarn that can be used in the invention is a twisted stainless steel filament yarn comprising 90 bundled drawn stainless steel filaments of equivalent diameter 14 μm twisted together with 100 turns per meter in Z-direction.

(13) Another example of a first yarn that can be used in the invention is a ply-twisted 90*2 tex stainless steel fiber yarn consisting out of stainless steel fibers of discrete length. The yarn is spun out of stretch broken bundled drawn stainless steel fibers of 12 μm equivalent diameter.

(14) In an example of an electrically conductive yarn according to the invention, the first yarn is a twisted stainless steel filament yarn comprising 275 bundled drawn stainless steel filaments of equivalent diameter 12 μm twisted with 100 turns per meter in Z-direction. The first yarn has been wrapped in S-direction with 300 turns per meter by a cotton yarn of 33 tex. About 60% of the surface of the conductive yarn is provided by the first yarn.

(15) In another example of an electrically conductive yarn according to the invention, the first yarn is a twisted stainless steel filament yarn comprising 275 bundled drawn stainless steel filaments of equivalent diameter 12 μm twisted with 100 turns per meter in Z-direction. The first yarn has been wrapped by two cotton yarns of 33 tex. The first cotton yarn is wrapped around the first yarn in S-direction with 300 turns per meter; and the second cotton yarn is wrapped around the first yarn in Z-direction with 300 turns per meter. More than 60% of the surface of the conductive yarn is provided by the first yarn.

(16) In another example of an electrically conductive yarn according to the invention, the first yarn is a ply-twisted 90*2 tex stainless steel fiber yarn consisting out of stainless steel fibers of discrete length. The first yarn is spun from stretch broken bundled drawn stainless steel fibers of 8 μm equivalent diameter. The first yarn has been wrapped in S-direction with 300 turns per meter by a cotton yarn of 33 tex. More than 60% of the surface of the conductive yarn is provided by the first yarn.

(17) In another example of an electrically conductive yarn according to the invention, the first yarn is a ply-twisted 90*2 tex stainless steel fiber yarn consisting out of stainless steel fibers of discrete length. The first yarn is spun from stretch broken bundled drawn stainless steel fibers of 8 μm equivalent diameter. The first yarn has been wrapped by two cotton yarns of 20 tex. The first cotton yarn is wrapped around the first yarn in S-direction with 600 turns per meter; and the second cotton yarn is wrapped around the first yarn in Z-direction with 600 turns per meter.