| 摘要 |
PURPOSE: To maintain the traveling performance on icy and snowy roads and improve wear resistance by providing connection parts cut off by blocks which are raised up from the groove bottom and both ends in the circumferential direction of which are adjacent to each other, and cracked grooves in lateral grooves, and setting the heights and time widths of the blocks and the connection parts to specified values. CONSTITUTION: A tire is divided into blocks 5 by longitudinal grooves 2 and lateral grooves 3, and connection parts 9 cut off by the blocks 5 which are raised up from the groove bottom 3A and both ends in the circumferential direction of tire of which are adjacent to each other in the circumferential direction of tire, and cracked grooves 7, are provided in the lateral grooves 3. The height h1 of the connection part 9 from the groove bottom 3A of the connection part 9 to the surface of the connection part 9 is regarded as constant, and the ratio (h1/H) of the height of the connection part to the height H of the block 5 is taken to 0.4 to 0.7. The width w1 of the connection part in the axial direction is regarded as almost constant, and the ratio (w1/H) of the width to the width W of the block is taken to 0.3 to 0.6. Further, the sum of height ratio (h1/H) and the width ratio (w1/W) is taken to 0.8 to 1.1. Thus, the traveling performance on icy and snowy road can be maintained, and wear resistance, wear resistance to heel and toe can be enhanced to improve the durability. |
