| 摘要 |
PROBLEM TO BE SOLVED: To improve wet skid characteristic, external appearance, and deflected abrasion proof during running and at the end of running by setting depth and width of a hot water-groove placed in a flat of a tread, and placing a given-size notched groove at end to the main groove of the hot water groove. SOLUTION: In a pneumatic tire for heavy load having plural flats 4 which are sectioned by plural main grooves 3 spreading circumferentially on the step surface of a tire, at least one of flats 4 has a hot water groove 5 which contacts with the circumferential main groove, is 1-7 mm in depth, 1.5-5 mm in width, a notched groove 6 is arranged at the opening end to the main groove 3 of a hot water groove 5, the depth of the notched groove 6 is two-thirds of that of the main groove 3 or equal to that of the main groove 3, and its length is 2-6 mm. Width of a part of the notched groove 6 which contacts with the circumferential main groove is preferably 1-3 times of the width of the hot water groove, width of the notched groove 6 is preferably 5-30% of tread width TW. |
