Pneumatic tire

摘要

A tire contour shape is formed by a single arc in a condition in which tire flattening rate is more than 55% and less than 70% and internal pressure is 5%. Shoulder lateral grooves extend at an angle α of 80 to 90° from the axially outer side of the tread ground-contact edge to the axially inner side of the tire, and the tire axially inner ends terminate within the shoulder land portion. A tire axial distance Ds between the tire axially inner end and the shoulder circumferential main groove is in the range of 3.5 to 5.5 mm, the shoulder lateral groove has the deepest part where the groove depth is largest, and the groove depth of the deepest part is 70 to 90% of the groove depth of the shoulder circumferential main grooves.

主权项

1. A pneumatic tire with a tire flattening rate of more than 55% and less than 70%, wherein
on a meridian cross section of a tire which is mounted on a standard wheel rim, and in a condition with an internal pressure of 5%, which is 5% of standard internal pressure, a contour line of a surface of a tread portion forms an arc having a single radius of curvature, the tread portion comprising circumferential main grooves including shoulder circumferential main grooves which continuously extend in a tire circumferential direction and are arranged at the axial outermost side of the tire, and crown circumferential main grooves arranged on the tire axial inner side of the shoulder circumferential main grooves and on both sides of a tire equator, shoulder land portions disposed on the tire axial outer side of the shoulder circumferential main grooves and middle land portions arranged between the crown circumferential main grooves and the shoulder circumferential main grooves, each of the shoulder land portions is provided with a plurality of shoulder lateral grooves extending from the tire axial outer side of a tread ground-contact edge to a tire axial inner side and an inner end of the shoulder lateral grooves terminating within the shoulder land portions, the shoulder lateral grooves have an angle α with respect to the tire circumferential direction in a range of 80 to 90° and a tire axial distance Ds between the tire axially inner end and the shoulder circumferential main groove is in a range of 3.5 to 5.5 mm, the shoulder lateral grooves have the deepest part where the groove depth is largest and the groove depth of the deepest part is made 70 to 90% of the groove depth of the shoulder circumferential main groove, each of the middle land portions is provided with a plurality of middle inclined grooves extending at an angle β of 0 to 45° with respect to the circumferential direction, extending axially inward from the shoulder circumferential main groove, and an inner end of the middle inclined grooves terminate within the middle land portions, each of the middle inclined groove includes a linear groove section which linearly extends axially inward at an angle β1 of 20° or less with respect to the tire circumferential direction, and a connecting groove portion which extends from the linear groove portion to the shoulder circumferential main groove while arcuately bending and/or polygonally curving, such that the angle β sequentially increases, axially outwardly.