Sumitomo Rubber Industries Limited

Yoshihiro Hada

Hiroshi Okagawa

Naoya Nagahara

Kiyotaka Ueyama

Junichi Nagata

A pneumatic tire includes a tread, a pair of sidewalls extending from edges of the tread substantially in a radially inward direction, a pair of clinches extending from edges of the sidewalls substantially in the radially inward direction, a pair of beads positioned on axially inner sides of the clinches, and a carcass extending along an inner side of the tread and sidewalls such that the carcass is bridging the pair of beads. Each bead includes a fitting portion extending in a circumferential direction and formed to be fitted to a rim, the fitting portion has a bottom surface positioned on a radially inner side of the fitting portion and a side surface positioned on an axially outer side of the fitting portion, the bottom surface includes a heel on the axially outer side of the fitting portion, and the side surface includes a concave extending in the circumferential direction.

Pneumatic tire

To make it possible to enhance uneven wear resistance while maintaining drainage performance, a pneumatic tire includes a left-right asymmetric tread pattern having a designated mounting orientation with respect to a vehicle. Vertical grooves include an inner shoulder circumferential groove disposed on an innermost side of the vehicle, and an outer shoulder circumferential groove disposed on an outermost side of the vehicle. Lateral grooves include inner shoulder lateral grooves and outer shoulder lateral grooves. The inner shoulder lateral groove includes a first inner shoulder lateral groove which extends inward in a tire axial direction from an outer side of a vehicle-inner side tread edge and terminates without reaching the inner shoulder circumferential groove, and a second inner shoulder lateral groove which extends inward in the tire axial direction from an outer side of the vehicle-inner side tread edge and opens in the inner shoulder circumferential groove.

Pneumatic tire having asymmetric tread pattern

A pneumatic tire comprises: a tread portion with an inboard and an outboard tread edges; a pair of inboard and outboard center main grooves to define a center portion therebetween; a pair of inboard and outboard shoulder main grooves; an inboard middle portion between the inboard center and shoulder main grooves; an outboard middle portion between the outboard center and shoulder main grooves; an inboard shoulder portion defined the axially outside of the inboard shoulder main groove; an outboard shoulder portion defined the axially outside of the outboard shoulder main groove; the outboard shoulder main groove with a groove width smaller than those of other main grooves; the outboard middle portion having a width larger than that of the inboard middle portion; and a plurality of outboard shoulder lateral grooves each extending from the outboard tread edge to its inner end terminating on the outboard middle portion.

A tread portionof a pneumatic tire is divided by a center longitudinal groove and a shoulder longitudinal groove into a center land portion, an outer middle land portionA, an inner middle land portionB, an outer shoulder land portionA, and an inner shoulder land portionB. The outer shoulder land portionA includes an array of outer shoulder blockswhich are sectioned by outer shoulder lateral groovesA. The inner shoulder land portionB includes inner shoulder lateral grooveshaving an inner endand an outer endin the land portionB, and inner shoulder auxiliary groovesdisposed between the inner shoulder lateral grooveswhich are circumferentially adjacent to each other and having inner endsand outer endsin the land portionB.

A pneumatic tirehaving excellent on-snow performances improved with maintaining steering stability and uneven wear resistance and including tread portionhaving a pair of crown circumferential grooveswhich extend continuously in the tire circumferential direction on both sides of tire equator C and have groove edges, one edgeextending in such a zigzag form that italic L-shaped groove edge segmentsare continuously connected to each other in the circumferential direction, and the other edgeextending in such a wavy form that circular arc groove edge segmentseach having a circular arc shape convex toward a groove center are continuously connected to each other in the circumferential direction, wherein each of the italic L-shaped groove edge segmentscomprises long side partinclined at an angle of 1 to 20&#xb0; with respect to the circumferential direction, and short side parthaving a circumferential length smaller than that of the long side partand inclined in the opposite direction to the long side partwith respect to the circumferential direction.

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Kobe, Japan

Yoshihiro Hada