| 摘要 |
PURPOSE:To prevent the occurrence of tearing of a rib, by a method wherein, in a rib tire for car, a crown radius, a distance between a main groove on the shoulder side and the center of a tread, a distance between a shoulder point and the edge part of a main groove nearmost a shoulder, and the slanted angle of a main groove wall are specified. CONSTITUTION:Values are specified such that a radius R of a tire crown is set to 25-50% of an outer diameter D of a tire, a groove 5a on the shoulder side nearmost a shoulder 3 is positioned at a distance La of 20-38% of a width T of a tread from a center E of a tread, a slanted angle theta of the groove wall of the main groove 5a with the equator surface of a tire is 15-32 deg., a distance Lb between a portion, where the edge part of the main groove 5a is nearmost the shoulder 3, and a shoulder point 4 is 12-24% of the width T of the tread, and a product of the slanted angle theta and a ratio of the width T of the tread to the distance Lb is 2.8 or more. This prevents a shoulder rib 5b from being worn in a deviating manner and the occurrence of tearing of a rib. |
