Patent ID: 9056528
Filing Date: 2015-06-16
Classification: B60C,Y10T

Abstract:
1. A pneumatic tire comprising: a carcass that is disposed toroidally bridging a pair of bead portions, the carcass having a carcass ply that includes plural radial carcass cords and that is equipped with a body portion positioned between the bead portions and with turn-back portions turned back from an inner side to an outer side around bead cores of the bead portions, and the carcass having first sections in which an inter-cord distance between the body portion and the turn-back portions gradually decreases outward in a tire radial direction from the bead cores, second sections that are disposed on the tire radial direction outer sides of the first sections and in which the inter-cord distance between the body portion and the turn-back portions of the carcass ply gradually increases outward in the tire radial direction from the bead cores, and first distance-invariant sections that interconnect tire radial direction outside parts of the first sections and tire radial direction inside parts of the second sections and in which the inter-cord distance between the body portion and the turn-back portions is constant within ±10 percent; and stiffeners that are placed between the carcass body portion and the turn-back portions and extend outward in the tire radial direction from the bead cores, wherein a length of the first distance-invariant sections as measured along the tire radial direction is within a range of from 40% to 60% of a rim flange height of an applicable rim, and wherein the carcass further has third sections that are disposed on the tire radial direction outer sides of the second sections and in which the inter-cord distance between the body portion and the turn-back portions of the carcass ply gradually decreases outward in the tire radial direction from the bead cores and second distance-invariant sections that extend from tire radial direction outside parts of the third sections to tire radial direction outside parts of the turn-back portions and in which the inter-cord distance between the body portion and the turn-back portions is constant within ±10 percent, wherein a length of the second distance-invariant sections as measured along the tire radial direction is within a range of from 70% to 85% of a rim flange height of an applicable rim.