Patent ID: 6820670
Filing Date: 2004-11-23
Classification: B60C,Y10T

Abstract:
A pneumatic tire comprisinga pair of bead portions each provided therein with a bead core made of windings of at least one wire, a carcass ply of cords extending between the bead portions the outside of the tire to form a pair of turnup portions and a main portion therebetween, a rubber bead apex disposed radially outside the bead core and between each said turnup portion and the main portion, a fiber reinforced rubber spacer interposed between the bead core and the carcass ply to provide a positive distance between the carcass ply cords and bead core wire, said fiber reinforced rubber spacer having a securing portion which extends radially outwardly and axially outwardly from the axially inside of the bead core while separating from the bead core but contacting with the rubber bead apex, and a distance (L1, L2) between an outermost point of said securing portion and the bead core being in a range of from 0.05 to 1.0 time a height of the bead core, said fiber reinforced rubber spacer being made of a single rubber strip reinforced with organic fibers, said single rubber strip loosely wound at least once around the bead core to form a slack portion radially outside the bead core, and said securing portion formed by the slack portion, wherein said single rubber strip is wound, starting from a position under the bead core, towards the axially inside of the tire, and after wound one or more times it is continuously wound toward the radially outside, but from a certain point, it separate from the previous winding and extends radially outwardly along the carcass ply main portion while contacting with an axially inside of the rubber bead apex, so that a distance between a radially outer end of this radially outwardly extending portion and the bead core is in a range of from 0.05 to 1.0 times the height of the bead core.