| 摘要 |
PROBLEM TO BE SOLVED: To remarkably improve on-ice performance, by optimizing a tread pattern. SOLUTION: In this pneumatic tire, a block group G<SB>B</SB>formed by mutually densely arranging a plurality of independent blocks 3 partitioned by a groove, is arranged in at least part of a tread part 1. Assuming the reference pitch length of the blocks 3 in the block group G<SB>B</SB>as P(mm), the width of the block group G<SB>B</SB>as W(mm), the number of blocks 3 existing in a reference area Z of the block group G<SB>B</SB>partitioned by the reference pitch length P and the width W as (a) pieces, and the negative ratio in the reference area Z as N(%), the block number density S per unit actual grounding area of the block group G<SB>B</SB>given by a/(P×W)×(1-N/100) falls within a range of 0.003 piece/mm<SP>2</SP>to 0.04 piece/mm<SP>2</SP>. The blocks 3 are respectively formed in a pentagonal shape, and are mutually formed in the same size. COPYRIGHT: (C)2010,JPO&INPIT |
