Patent ID: 6533011
Filing Date: 2003-03-18
Classification: B60C,Y10T

Abstract:
A pneumatic tire, comprising:at least one carcass ply having steel cords arranged substantially in a radial direction of the tire, folded turned up araound a bead core; a belt layer arranged on an outer side of a crown portion of said at least one carcass ply to have an overlapping portion with the folded portion of said at least one carcass ply; a first reinforcing rubber layer arranged between a body portion of said at least one carcass ply and said folded portion thereof; a second reinforcing rubber layer arranged inside the body portion of said at least one carcass ply, over a region from a tire shoulder portion to a bead portion, with its thickness gradually reduced from a central portion to opposing end portions; wherein overlapping width W2 from an upper end position RF of said second rubber reinforcing layer to an end BE of said belt layer is 7% to 33% of the width BW of the belt layer; and cross sectional widths G1W, G2W, and G3W representing minimum widths between an inner surface of the tire and respective side-wall outer surface positions G1, G2 and G3 at portions of Â¼GL, {fraction (2/4)}GL, and Â¾GL corresponding to cross sectional height GL from an upper end of the bead core to a tire outer peripheral end divided equally by 4 satisfy the following relations: G3W/G1W=0.85 to 0.95, and G2W/G1W=1.0 to 1.05.