| 摘要 |
PURPOSE: To facilitate formation of a line of blocks of different block lengths by providing the blocks to exist on both sides of a pitch partition line for the pitch partition line to regulate disposition pitch positions in the block line, and providing lug grooves to exist to be free from the pitch partition line. CONSTITUTION: A tread 1 of a radial tire is provided with at least two circumferential main grooves 2, 3, lug grooves 4, 5 are extended between the adjacent main grooves 2, 3, and a block line 10 comprising a number of blocks 6-9 is formed of the main grooves 2, 3, and lug grooves 4, 5. In this case, as pitch partition lines L1 -L6 extended through respective points Z1 -Z6 in the width direction of a tread 1 are drawn, the blocks 6-9 are provided to exist on both sides of the respective pitch partition lines L2 -L5 , and the lug grooves 4, 5 are provided to exist to be free from the pitch partition lines L1 -L6 . The block line can thus be formed including blocks of different lengths as measured about the same circle over the sorts of disposition pitches. |
