| 摘要 |
PROBLEM TO BE SOLVED: To improve heat radiation performance in circumferential grooves at shoulder part sides of a plurality of blocks.SOLUTION: Blocks 41 have: first wall faces 42 on which lateral grooves 14 are formed from positions opened to a first circumferential groove 11 toward an upstream side G of air currents; second wall faces 43 on which the lateral grooves 14 are formed from positions opened to a second circumferential groove 12 toward the upstream side G of the air currents; and block corner parts 44 formed at the positions where the lateral grooves 14 are opened to the first circumferential groove 11. Virtual extension surfaces 46 of the first wall faces 42 of the blocks 41 on the upstream side G cross the block corner parts 44 of the blocks 41 on a downstream side H of air currents, or pass through a position in the first circumferential groove 11, at the block corner parts 44 closer to a tread center part 3. A groove width W of the second circumferential groove 12 gets wider gradually toward the downstream side H of the air currents on the second wall faces 43.SELECTED DRAWING: Figure 2 |
