| 摘要 |
PURPOSE:To decrease the contact pressure of a range along a rib or a block formed at a tire tread surface and minimize slippage for prevention of uneven wear by forming a sipe open to both the side surfaces in the axial direction of the rib or the block at the rib or the block, and increasing the depth of the sipe gradually as it leads to both the sides in the axial direction of the rib or the block. CONSTITUTION:A tire tread surface is provided with peripheral grooves 1 running along the peripheral direction and lateral grooves 2 running in the axial direction formed in a grid shape. Blocks 3 are formed, surrounded by the peripheral grooves 1 and the lateral grooves 2. The blocks 3 are provided with the sipes 4 along the axial direction, which are open to both the side surfaces in the axial direction of the blocks 3 and their depth increases gradually as it leads to both the sides in the axial direction of the blocks 3. The groove bottom 4a of the sipe 4 is formed into an arc shape, so that contact pressure in a range along the peripheral groove 1 of the block 3 is decreased and slippage is minimized. It is thus possible to prevent uneven wear generated at the block 3 from occurring and provide mild behavior for the roughness of the road surface. |
