| 摘要 |
<p>Disclosed is a pneumatic tire capable of enhancing durability and reducing rolling resistance while maintaining lateral stiffness. The pneumatic tire of the present invention is provided with at least one carcass ply laid therein so as to extend between a pair of bead portions and formed of organic fiber cords. The tire has a casing structure where a bead filler is arranged to an outer periphery of a bead core buried in the bead portion. Additionally, an air pressure corresponding to the maximum load capacity of the tire is in a range from 350 to 650 kPa. The pneumatic tire is characterized in that the bead filler includes a plurality of rubber layers stacked in a radial direction of the tire, and a cross-sectional area S 1 , a hardness Hs 1 , and a loss tangent tan´ 1 of the rubber layer on the outermost peripheral side; a cross-sectional area S 2 , a hardness Hs 2 , and a loss tangent tan´ 2 of the rubber layer on the innermost peripheral side; and a ratio of a bead filler height BFH to a tire cross-sectional height SH are set to have the following relations (1) to (5): S 1 × tan´ 1 / ( S 1 × tan´ 1 ) + ( S 2 × tan´ 2 ) = 0.25 to 0.40 , S 1 × Hs 1 / ( S 1 × Hs 1 ) + ( S 2 × Hs 2 ) = 0.35 to 0.50 , BFH / SH = 0.25 to 0.60 , Hs 2 - Hs 1 = 10 to 25 , and tan´ 1 ‰ 0.1 and tan´ 2 - tan´ 1 ‰ 0.1.</p> |
