Patent ID: 8955564
Filing Date: 2015-02-17
Classification: B60C

Abstract:
1. A pneumatic tire comprising, in a tread portion, at least two block groups, each block group being composed of a plurality of independent blocks defined by grooves, wherein the block groups have at least two different values of block number densities D, each of the block number densities D being represented by the formula: wherein PL (mm) represents a reference pitch length of the block in the block group, W (mm) represents a width of the block group, a (pieces) represents the number of the blocks existing in a reference zone of the block group, the reference zone being demarcated by the reference pitch length PL and the width W, and N (%) represents a negative ratio in the reference zone; wherein the block number density of at least one block group is within a range of 0.003 (pieces/mm wherein the blocks in at least one of the block groups are arranged to be adjacent circumferentially, diagonally, and widthwise, and a groove distance (BGL) between blocks adjacent to each other in the tread circumferential direction is larger than a groove distance (BGO) between blocks adjacent to each other in a direction diagonal to the tread circumferential direction, and a groove distance (BGW) between blocks adjacent to each other in the tread width direction and across a groove between the blocks adjacent to each other in the tread circumferential direction is smaller than a length (BW) of each of the independent blocks in the tread width direction.