| 摘要 |
PURPOSE:To properly avoid the warping of a tread rubber-buried belt by a method in which a recession corresponding to a peripheral groove is formed on the outer surface of a tread rubber layer, and the green tire is shaped and hardened by vulcanization. CONSTITUTION:A tread portion having continuously or intermittently heaving projections for rejecting the catch of gravels on the bottoms of single or plural peripheral grooves continuously formed along the periphery of its central region is provided for a tire. A peripheral groove 5 is provided in the central region W2 of the tread and many projections 11 for rejecting the catch of gravels are formed intermittently on the bottom of the groove 5. Also, a pair of peripheral grooves 10 of the same dimension as the groove 5 are arranged even in both-side regions 9, without the projection 11. The contour of the tread is shaped by pushing-out of the recession 1' to the corresponding position of the groove 5 in the central region of the tire. The recession 1' is of a depth corresponding to 80% of the depth of the groove 5 and of a width corresponding to 120% of the width of the groove 5. These parts are assembled to match with the groove 5 of the tire with the recession 1' of the tread and hardened by vulcanization in vulcanizing molds. |
