Automobile pneumatic tire

Abstract

Provided is an automobile pneumatic tire such that the tire weight and rolling resistance can be greatly decreased without detracting from necessary tire performance. In a pneumatic tire, at least one layer of a carcass layer is installed between a pair of bead portions, a bead core is embedded in each bead portion, at least one layer of a reinforcement layer is disposed on an outer periphery side of the carcass layer, and a tread rubber layer is layered on the outer periphery side of the reinforcement layer. When a pair of first boundary lines is defined that passes a point of intersection of an extension of a side arc forming a tread profile and an extension of a shoulder arc and orthogonal to a tire inner surface, a pair of second boundary lines is defined passing a rim check line and orthogonal to the tire inner surface, a first region is partitioned between the pair of first boundary lines, a second region is partitioned between the first boundary lines and the second boundary lines, a third region is partitioned closer to a bead toe than to the second boundary lines, the first to the third regions have cross sectional areas (mm2) of SA, SB, and SC, respectively, and the first to the third regions respectively have periphery lengths (mm) of a, b, and c along the tire inner surface, the relationships 7.5 <= SA/a <= 11.5 and 2.0 <= SB/b <= 6.0 are satisfied with respect to the ratios SA/a and SB/b.

Description

technical field [0001] The present invention relates to a pneumatic tire suitable for a standard mounting tire of a passenger car, and more particularly, to a pneumatic tire for a passenger car that can significantly reduce tire weight and rolling resistance without affecting desired tire performance. Background technique [0002] Pneumatic tires for passenger vehicles generally include: a tread portion extending in the tire circumferential direction and having an annular shape; a pair of sidewall portions arranged on both sides of the tread portion; and a pair of The bead portion is disposed on the inner side in the tire radial direction of these sidewall portions, and has a structure in which a carcass is bridged between the pair of bead portions, a bead core is buried in each bead portion, and a bead core is embedded in each bead portion. A belt layer is arranged on the outer peripheral side of the layer, and a tread rubber layer is laminated on the outer peripheral side ...

AI Technical Summary

Problems solved by technology

[0004] However, the current situation is that the traditional method focuses on individual parts of the pneumatic tire to achieve weight reduction, so the tire weight and rolling resistance cannot be greatly reduced, and the problems that arise when the pneumatic tire is greatly reduced in each area are not fully considered.

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