| 摘要 |
PURPOSE:To lengthen the service life and to prevent biting of stone, in a pneumatic tire for a bus, by forming radial inner and outer areas and an intermediate area on the sidewall of a main groove and making the angle between respective area side walls and a normal line to a tread face larger at the inner and outer area sides than at the intermediate area side. CONSTITUTION:A radial inner area 26, an outer area 25 and an intermediate area 27 are formed on one sidewall 21a of a main groove 21. The angles alpha25, alpha26, alpha27 between a normal line N to the surface 23b of the tread 23 and the other area 25, the inner area 26 and the intermediate area 27 are set such that alpha25, alpha26>alpha27. Since the angles in the inner and outer areas are large, the tire is prevented from biting a stone while the intermediate area is elongated and the groove depth can be ensured sufficiently. Consequently, the service life is lengthened and the biting of stone is prevented. |
