Patent ID: 8925601
Filing Date: 2015-01-06
Classification: B60C,Y10S

Abstract:
1. A pneumatic tire comprising a tread portion provided along each tread edge with shoulder blocks defined by a circumferentially continuously extending shoulder main groove and a plurality of shoulder lateral grooves extending from the shoulder main groove to said tread edge, wherein the shoulder main groove is made up of a plurality of circumferentially arranged groove segments curved convexly toward the tire equator so that each of the groove segments comprises a first inclined part inclined to one axial direction and a second inclined part inclined to the other axial direction, the shoulder lateral grooves each extend at an angle of from 45 to 90 degrees with respect to the tire circumferential direction, and are respectively coupled with the first inclined parts of the groove segments, the shoulder blocks are each subdivided by a shoulder sub groove, the shoulder sub groove extends at an angle of from 15 to 45 degrees with respect to the tire circumferential direction, and has an axially outer end connected with one of the shoulder lateral grooves and an axially inner end coupled with one of the second inclined parts to subdivide the shoulder block into an axially inner part and an axially outer part, the maximum axial width Wa of the axially outer part is more than 1.0 times and not more than 2.0 times the minimum axial width Wb of the axially outer part when measured axially between the axially outer edge of the shoulder sub groove and the axially outer edge of the shoulder block, the depth of each said shoulder lateral groove is not less than 50% and not more than 70% of the depth of the shoulder main groove, and gradually increases toward the tread edge so as to form a step on the axially outside of said axially outer end of the shoulder sub groove, each said shoulder lateral groove has opposite edges smoothly curved to have a groove width gradually increasing from the axially inside to the axially outside of the tire, and a corner of the axially outer part formed between said axially outer edge of the shoulder block and the shoulder lateral groove is provided with a chamfer having a triangular shape in the top view of the axially outer part.