Patent ID: 9586445
Date: 2017-03-07
CPC Classifications: B60C

Claim:
1. A heavy duty tire comprising: bead portions; sidewall portions continuous to the respective bead portions; a tread portion to be in contact with a road surface; and buttress portions each extending inward in a tire radial direction from a corresponding tread end portion of the tread portion and continuous to a corresponding one of the sidewall portions, the tread end portion being located on an outer side, in a width direction, of the tread portion, wherein in the tread portion, a plurality of lateral groove portions intersecting with a tire circumferential direction and land portions defined by the lateral groove portions are formed, at least one end portion in the tread width direction of each lateral groove portion opens to a tread end, the land portions each having a side surface intersecting with the width direction of the tread portion, a length, in the tread width direction, of each of the land portions decreases from one side to an other side in the tire circumferential direction, the length, in the tread width direction, of the land portion is a length from a groove end reference line extending in the tire circumferential direction to the tread end, and the groove end reference line is defined by inner ends, in the tread width direction, of the respective lateral groove portions adjacent to each other in the tire circumferential direction with the land portion interposed therebetween, wherein: the side surface is a surface on an outer side in the tread width direction of each of the land portion, an end portion on the other side in the tire circumferential direction of the side surface is located on an inner side in the tread width direction of an end portion on the one side in the tire circumferential direction of the side surface, an extending direction of the lateral groove portion formed on the other side in the tire circumferential direction of the land portion, is inclined with respect to a tread width direction line which extends along the tread width direction, in a plan view of the tread portion, an angle between the extending direction of the lateral groove portion and the tread width direction line is smaller than an angle between the side surface and the tread width direction line, and wherein a curved surface portion configured to abut on the groove bottom portions of the lateral groove portions is formed on a portion having a vertex of a surface of the tread portion, the side surface formed on the outer side of the land portion, and a side surface formed on the other side in the tire circumferential direction of the land portion, wherein the vertex has an obtuse angle between the side surface of the land portion and the wall surface of a corresponding one of the lateral groove portions, wherein the land portions comprises: wherein the first and the second side surfaces extend in a substantially parallel direction with each other.