Sumitomo Rubber Industries Limited

Kosuke Nakano

Masayuki Fujita

Tomoyuki Kujime

Naoki Sugiyama

Hiroshi Okagawa

Daiki Imai

Daisuke Aoki

The tire whose mounting position relative to a vehicle is specified, comprises a tread portion having a first tread edge and a second tread edge, and provided with three main grooves and four land portions. The main grooves include a first shoulder main groove, a second shoulder main groove, and a crown main groove. The land portions include a first middle land portion and a second middle land portion. The first middle land portion is disposed on the tire equator. The first middle land portion is provided with first transverse narrow grooves. The first transverse narrow groove comprises a first deep portion, a second deep portion and a first shallow portion therebetween to improve steering stability and ride comfort.

Tire

A run-flat tire comprises a tread portion, sidewall portions, bead portions, and a carcass ply extending between the bead portions. The sidewall portions are each provided therein with a sidewall reinforcing rubber layer having a crescent-shaped cross sectional shape and disposed on the axially inside of the carcass ply. The sidewall portions are each provided in the axially outer surface thereof with a rim protector which projects radially outward most on the radially outside of the radially inner edge of the sidewall reinforcing rubber layer. The bead portions are each provided therein with an axially inside core and an axially outside core between which each radially inner edge portion of the carcass ply is secured. When measured along a normal line drawn normally to the carcass ply from an apex of the rim protector, the thickness of the sidewall reinforcing rubber layer is in a range of from 29% to 35% of the thickness of the tire.

Run-flat tire

Growing community of inventors

Kobe, Japan

Kosuke Nakano