| 摘要 |
PROBLEM TO BE SOLVED: To simultaneously improve ice road performance and abrasion resistance performance by furnishing a plural number of waveform sipes extending in a waveform shape in the tire cross direction on a block surface and waveform hills of which extend in an inclined shape in the block inside direction and arranging the adjoining waveform sipes in directions where their hills are inclined in opposite directions to each other. SOLUTION: A waveform sipe 4a out of the waveform sipes 4 is inclined at an angle that an inclinationθof a waveform hill 8 makes 30-60 deg. against a normal 9', and a hill 8 of a waveform sipe 4b adjoining it is inclined in the opposite direction. In this constitution, ice road performance is imporoved by an edge effect of the waveform sipes 4 longer in sipe length formed on a block surface, while at the time of travelling on a dry road surface, the waveform hills 8 of the waveform sipes 4a, 4b adjoin each other in reversely inclined structure even when a load from any direction at the time of starting works on a block, and accordingly, lowering of block rigidity is stably restrained in structure, and it is possible to prevent falling and deformation of the block. |
