The Yokohama Rubber Co., Ltd.

Takashi Shibai

Jun Matsuda

Yoshiaki Hashimura

Yoshifumi Koishikawa

Zenichiro Shida

Hideki Seto

Toyoaki Endo

A pneumatic tire is provided, the pneumatic tire including a tread portion, sidewall portions, and bead portions, and the pneumatic tire includes, in the tread portion, a center main groove extending in a tire circumferential direction and a shoulder main groove extending in the tire circumferential direction on the outside of the center main groove; a land portion between the main grooves; lug grooves extending inward in a tire lateral direction from the shoulder main groove and terminating without communicating with the center main groove; a bent portion bending toward one side in the tire circumferential direction, at a terminating end of each of the lug grooves; and a raised bottom portion included in the bent portion, creating a level difference with respect to a lug groove, and being shallower than the lug groove.

Pneumatic tire

A pneumatic tire includes a tread; sidewalls; and beads. The tread includes main grooves, including a center main groove extending in a tire circumferential direction and a pair of shoulder main grooves extending in the tire circumferential direction, and land portions defined between the main grooves. At least one of the land portions includes lug grooves extending from at least one of the main grooves defining the at least one of the land portions and terminating within the at least one of the land portions. At least one of the lug grooves includes a raised bottom portion that is shallower than a groove bottom at a portion on an opening end side and a communicating portion that extends in a longitudinal direction of the at least one of the lug grooves following the raised bottom portion and is deeper than the raised bottom portion.

A pneumatic tire includes a carcass layer and belt layers including belt cords inclined with respect to a circumferential direction, the belt cords of different layers being arranged in a criss-cross manner. In at least one belt layer, an inclination angle &#x3b1; of the belt cords with respect to the circumferential direction at a center position and an inclination angle &#x3b2; of the belt cords with respect to the circumferential direction at a belt end position satisfy 15&#xb0;&#x2264;&#x3b2;&#x3c;&#x3b1;&#x2264;35&#xb0;. A maximum ground contact length Land a ground contact length Lsatisfy 0.8&#x2264;L/L, where Lis the maximum ground contact length in the circumferential direction, Wis a maximum ground contact width in a radial direction, and Lis the ground contact length in the circumferential direction at a position 40% of Wfrom the center position outward in a lateral direction.

Provided is a pneumatic tire including a tread portion, sidewall portions, and bead portions. The tread portion comprises a center main groove extending in the tire circumferential direction and a shoulder main groove located outward of the center main groove and extending in the tire circumferential direction. A land portion is defined between the center main groove and the shoulder main groove. The center main groove has a zigzag shape in the tire circumferential direction. Lug grooves extending inward from the shoulder main groove in the tire lateral direction and terminating without communicating with the center main groove are provided in the land portion. A bent portion bent toward a first side in the tire circumferential direction is formed at a terminating end of each of the lug grooves. Narrow grooves extending discontinuously in the tire circumferential direction without communicating with the bent portions are formed in the land portion.

The pneumatic tire according to the present technology includes a tread portion, sidewall portions, and bead portions, and has a designated mounting direction on a vehicle. The pneumatic tire is provided, in the tread portion, with four main grooves including a pair of center main grooves extending in the tire circumferential direction and a pair of shoulder main grooves located outside the center main grooves and extending in the tire circumferential direction; these main grooves define five rows of land portions; the center main groove on the vehicle outer side has a zigzag shape in the tire circumferential direction; and a plurality of lug grooves extending from the main grooves, except the center main groove having a zigzag shape, toward both sides in the tire lateral direction and terminating in the land portions are provided in the tread portion.

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Hiratsuka, Japan

Takashi Shibai