Patent ID: 9616714
Date: 2017-04-11
CPC Classifications: B60C

Claim:
1. A heavy duty pneumatic tire comprising: a tread portion provided with at least three circumferentially and continuously extending main grooves and a plurality of lateral grooves extending between adjacent main grooves or between one main groove and a tread edge to form a block row comprising a plurality of blocks; the at least three main grooves comprising a pair of crown main grooves disposed on both sides of a tire equator and a pair of middle main grooves disposed axially outward of the crown main grooves; the middle main grooves comprising shallow bottom parts having a groove depth in a range of from 15% to 70% in relation to a maximum groove depth of the crown main grooves; the shallow bottom parts comprising first shallow bottom parts and second shallow bottom parts alternately arranged in a circumferential direction of the tire, the second shallow bottom parts having groove depths larger than groove depths of the first shallow bottom parts; and the block row comprising a plurality of pitch elements each of which consists of circumferentially adjacent one lateral groove and one block, wherein the tread portion has a land ratio in a range of from 70% to 80%, the block row comprises a number of pitch elements in a range of from 40 to 50, and each lateral groove has a groove width in a range of from 5% to 15% in relation to a circumferential length of the block in each pitch element.