Patent ID: 11919335
Assignee: BRIDGESTONE CORPORATION
Field: Transport (Mechanical engineering)
Classification: CPC B | IPC B

Claim 14:
15. A pneumatic tire comprising, on a tread surface, a plurality of circumferential main grooves extending in a tire circumferential direction, and a plurality of land portions defined between circumferential main grooves adjacent in a tire width direction among the plurality of circumferential main grooves or by the circumferential main grooves and tread edges, wherein
the land portions include at least one circumferential sipe extending in the tire circumferential direction,
the circumferential sipe includes a plurality of widened portions, having a sipe width larger than in other portions, arranged in the tire circumferential direction,
in a case in which a circumferential main groove is located on a tire equatorial plane, two land portions defined by the circumferential main groove located on the tire equatorial plane are designated as center land portions, in a case in which a land portion is located on the tire equatorial plane, the land portion is designated as a center land portion, land portions adjacent to the tread edges are designated as shoulder land portions, and each land portion other than the center land portion and the shoulder land portions is designated as an intermediate land portion, and
in a reference state such that the pneumatic tire is mounted on an applicable rim, filled to a prescribed internal pressure, and under no load,
each widened portion is formed only from a portion that, from one side towards another side in the tire circumferential direction, extends from the tread surface inward in a tire radial direction,
a tire radial area from a sipe bottom of the circumferential sipe to ⅓ of a sipe depth of the circumferential sipe is designated as a sipe bottom area, and
the sipe width of the widened portion at the sipe bottom area in the center land portion is larger than the sipe width of the widened portion at the sipe bottom area in the intermediate land portion.