US Patent No. 9,079,460

PNEUMATIC TIRE


Patent No. 9,079,460
Issue Date July 14, 2015
Title Pneumatic Tire
Inventorship Naoya Ochi, Higashimurayama (JP)
Assignee BRIDGESTONE CORPORATION, Tokyo (JP)

Claim of US Patent No. 9,079,460

1. A pneumatic tire in which a circumferential groove extending in a tire circumferential direction is formed by land portions
constituting a tread surface coming into contact with a road surface, wherein
a flat groove portion and an in-groove land portion are formed in the circumferential groove, the flat groove portion being
a flat surface of a groove bottom of the circumferential groove, the in-groove land portion being raised toward the tread
surface side from the groove bottom of the circumferential groove,

a plurality of narrow grooves extending in a tread width direction are formed in the in-groove land portion,
cutout portions extending respectively from the plurality of narrow grooves in the tread width direction are formed in a corresponding
one of the land portions and ending inside the land portion, wherein a width of each of the cutout portions in the tire circumferential
direction is substantially equal to a width of each of the narrow grooves in the tire circumferential direction, and

a width of the circumferential groove in the tread width direction is 5 to 30% of a width of the tread surface in the tread
width direction, wherein a depth from a groove bottom of each of the narrow grooves to an upper surface of the in-groove land
portion is 50 to 100% of a height from the groove bottom of the circumferential groove to the upper surface of the in-groove
land portion.