| 摘要 |
PROBLEM TO BE SOLVED: To significantly improve the level of uniformity and reduce a noise (hitting sound) by providing a tread pattern by which a V center block is formed with plural directional low tilted grooves extended in a V-shape at a specific angle of inclination in the peripheral direction. SOLUTION: First, a raw grooved tread 4 with a directional low tilted groove 1 and a recessed part 3 formed at a position corresponding to an angle of inclination of 5-30 deg., is manufactured. Next, the raw-grooved tread 4 is attached to a carcass and is formed to obtain a raw grooved tire. After that, the registration of the relative positions for the recessed part 3 of the raw grooved tire and a projecting part provided at a position corresponding to the directional low tilted groove 1 of a vulcanization mold is controlled so that the recessed part 3 coincides with the projecting part, while the raw grooved tire is mounted in the vulcanization mold. Finally, the vulcanization mold is closed and the raw grooved tire is vulcanized under specified temperature and pressure conditions. |
