Patent ID: 9174497
Filing Date: 2015-11-03
Classification: B60C

Abstract:
1. A pneumatic tire comprising a tread provided with at least two circumferential main grooves and a rib defined in a tread central portion by two of the circumferential main grooves, wherein an auxiliary groove is formed in the tread central portion, the auxiliary groove having a circumferential groove portion extending in a tire equator direction and an axial groove portion extending from an end of the circumferential groove portion in such a manner that the axial groove portion is bent at an acute angle to the circumferential groove portion, and at least an end of the auxiliary groove is open into one of the two circumferential main grooves, wherein the rib is located on the tire equator, wherein the circumferential groove portion of the auxiliary groove has a chamfered portion inclined with respect to a surface of the tread on at least one groove wall of both groove walls sectioning the circumferential groove portion, wherein the chamfered portion is formed on one groove wall of the circumferential groove portion only in a side of the axial groove portion, wherein the width of the chamfered portion gradually decreases from the axial groove portion side end of the circumferential groove portion to a terminated end of the circumferential groove portion, wherein the acute angle is formed between the circumferential groove portion and the axial groove portion, wherein the chamfered portion is provided only in a half tread portion on one side of the tire equator, and wherein the other half tread portion on the other side of the tire equator is not provided with an auxiliary groove having a chamfered circumferential groove portion extending in a tire equator direction and an axial groove portion extending from an end of the chamfered circumferential groove portion in such a manner that the axial groove portion is bent at an acute angle to the chamfered circumferential groove portion.