Tire having a conductivity path

Abstract

A tire includes a body ply sheet having a rubber core defined by a top surface having a length and a width, a bottom surface having substantially the same length and width, and side surfaces having a common height. The body ply sheet includes reinforcement cords spaced 0.1-4.0 mm apart from each other and spanning the width of the body ply sheet. Bleeder cords are disposed on the body ply sheet and spaced are 8-12 cm apart from each other. Conductive cords are also disposed on the body ply and are spaced 20-80 cm apart from each other. At least one of the conductive cords has a first end and a second end, the first end being located in a region within a middle 80% of a width of the circumferential tread.

What is claimed is: 
     
         1 . A tire comprising:
 a first annular bead and first abrasion area, wherein the first abrasion area has a resistivity of at least 5.9×10 7  ohm-cm;   a second annular bead and second abrasion area, wherein the second abrasion area has a resistivity of at least 5.9×10 7  ohm-cm;   a body ply extending between the first annular bead and the second annular bead, wherein the body ply contains reinforcement cords;   a circumferential belt disposed radially upward of the body ply and extending axially across a portion of the body ply;   at least one reinforcement ply disposed radially upward of the circumferential belt and extending axially across a portion of the body ply;   at least one cap ply disposed radially upward of the at least one reinforcement ply and extending axially across a portion of the body ply, wherein the cap ply has a resistivity of at least 13.0×10 7  ohm-cm;   a circumferential tread disposed radially upward of the circumferential belt and extending axially across a portion of the body ply, wherein the circumferential tread has resistivity of at least 13.7×10 7  ohm-cm;   a first sidewall extending between the first annular bead and a first shoulder, the first shoulder being associated with the circumferential tread, wherein the first sidewall has a resistivity of at least 11.9×10 7  ohm-cm;   a second sidewall extending between the second annular bead and a second shoulder, the second shoulder being associated with the circumferential tread, wherein the second sidewall has a resistivity of at least 11.9×10 7  ohm-cm; and   a plurality of bleeder cords associated with the body ply and disposed circumferentially about the tire, wherein the plurality of bleeder cords includes at least one conductive bleeder cord disposed radially between the circumferential tread and the body ply, wherein 10-40% of the cords in the plurality of bleeder cords are conductive bleeder cords that dissipate electric charge in the tire.   
     
     
         2 . The tire of  claim 1 , wherein the tire lacks a conductive antenna. 
     
     
         3 . The tire of  claim 1 , wherein the conductive bleeder cord is infused with carbon black. 
     
     
         4 . The tire of  claim 1 , wherein the conductive bleeder cord is a cotton cord coated with carbon black. 
     
     
         5 . The tire of  claim 4 , wherein the carbon black has conductivity between 0 Ω −1 m −1  and 300 Ω −1 m −1 . 
     
     
         6 . The tire of  claim 5 , wherein the carbon black coating is disposed linearly along a cotton cord. 
     
     
         7 . The tire of  claim 1 , wherein the at least one conductive bleeder cord has a first end and a second end, the first end being located in a region within a middle 80% of a width of the circumferential tread. 
     
     
         8 . The tire of  claim 1 , wherein the at least one conductive bleeder cord engages one other of the plurality of bleeder cords. 
     
     
         9 . The tire of  claim 8 , wherein the at least one conductive bleeder cord and the one other of the plurality of bleeder cords that are in engagement extend parallel to one another. 
     
     
         10 . The tire of  claim 8 , wherein the at least one conductive bleeder cord and the one other of the plurality of bleeder cords that are in engagement have substantially identical cross sections. 
     
     
         11 . The tire of  claim 8 , wherein the at least one conductive bleeder cord has an irregular cross section. 
     
     
         12 . The tire of  claim 8 , wherein the at least one conductive bleeder cord and the one other of the plurality of bleeder cords that are in engagement are joined to one another. 
     
     
         13 . The tire of  claim 8 , wherein a cross sectional area of the at least one conductive bleeder cord is 10% of a cross sectional area of the one other of the plurality of bleeder cords. 
     
     
         14 . A tire comprising:
 a circumferential tread; and   a body ply sheet disposed radially downward of the circumferential tread, the body ply sheet having a rubber core defined by a top surface having a length and a width, a bottom surface having substantially the same length and width, and side surfaces having a common height, wherein the rubber core is further defined by a top rubber layer and a bottom rubber layer, the body ply sheet further including:
 reinforcement cords disposed between the top rubber layer and the bottom rubber layer, wherein the reinforcement cords are spaced 0.1-4.0 mm apart from each other and span the width of the body ply sheet, 
 bleeder cords configured to vent gas from the tire during vulcanization, wherein the bleeder cords are disposed on the body ply sheet and spaced 8-12 cm apart from each other, and 
 conductive cords configured to dissipate electric charge from the tire after vulcanization, wherein the conductive cords are disposed on the body ply and spaced 20-80 cm apart from each other, at least one of the conductive cords having a first end and a second end, the first end being located in a region within a middle 80% of a width of the circumferential tread. 
   
     
     
         15 . The tire of  claim 14 , wherein the conductive cord further comprises a segment that extends from the body ply sheet. 
     
     
         16 . The tire of  claim 14 , wherein one of every five bleeder cords is a conductive cord. 
     
     
         17 . The tire of  claim 16 , wherein the conductive cords are infused with carbon black. 
     
     
         18 . A method of preparing a conductive tire comprising:
 providing body ply cords;   calendaring rubber around the body ply cords to form a body ply;   providing conductive cords selected from the group consisting of conductive bleeder cords and infused cords, wherein the conductive bleeder cords are formed by wetting bleeder cords and introducing the wetted bleeder cords to conductive carbon black to form conductive bleeder cords, and wherein the infused cords are formed by infusing cords with conductive carbon black;   positioning the conductive cords with respect to the body ply cords;   providing beads, sidewalls, a circumferential belt, and a tire tread, at least one of the conductive cords being positioned such that a first end of the at least one conductive cord is located in a region within a middle 80% of a width of the tire tread;   forming the body ply into an annulus in connection with the beads and sidewalls;   stitching the circumferential belt and tire tread to the annulus;   molding the body ply, beads, sidewalls and tire tread into a cured tire by placing the body ply, beads, sidewalls and tire tread into a mold and vulcanizing the tire;   removing the tire from the mold.   
     
     
         19 . The method of  claim 18 , wherein the conductive cords are positioned with respect to the body ply cords prior to calendaring rubber around the body ply cords. 
     
     
         20 . The method of  claim 18 , wherein the conductive cords are positioned on a body ply surface.