Sumitomo Rubber Industries Limited

Rena Onitsuka

Masayuki Fujita

Junya Sueno

Isao Sawakami

Ryuhei Sanae

Mahito Arai

Hiroyuki Nakayama

Daiki Imai

Masaki Terashima

Suxiang Yuan

Shigeki Nishijima

Tatsuya Sasaki

Yuan Suxiang

Tsukasa Yano

Yusuke Sueyoshi

A pneumatic tire includes a tread portion, a pair of sidewall portions, a pair of bead portions, a carcass extending between the pair of bead portions, and an inner rubber extending between the pair of bead portions on an inner side of the carcass. The inner rubber includes a first portion extending in the tread portion with a first thickness and a second portion extending in each of or one of the pair of sidewall portions with a second thickness. The first thickness is greater than the second thickness. In a tire meridian cross-section, a cross-sectional area of the inner rubber is in a range from 1.5% to 10% of an inner-cavity cross-sectional area of the pneumatic tire.

Pneumatic tire

A pneumatic tire comprises: a tread portion having a ground contacting surface; a sidewall portions having an outer surface; a bead portions; a carcass extending between the bead portions; and an inner rubber extending between bead portions. The inner rubber comprises a first portion extending through the tread portion with a first thickness t, and a second portion extending through the sidewall portion with a second thickness t. The first thickness tis more than the second thickness t. In a meridian cross section of the tire under its normal state, when a first reference point (Pb), a second reference point (Pb), a shoulder reference point (Ps), a reference line segment (Lb), and a shoulder line segment (Ls) are defined, then a length (L) of the shoulder line segment (Ls) is 85.9% to 89.3% of a length (L) of the reference line segment (Lb).

A mold includes a tread-forming surface to shape a tread surface. The tread-forming surface can include projections to form circumferential grooves, and land surface-forming portions to form land surfaces. Among the three land surface-forming portions aligned in an axial direction with the projections interposed therebetween, the land surface-forming portion located between the two projections can be a curved land surface-forming portion. A contour of the curved land surface-forming portion can be represented by one or more circular arcs. A boundary between a reference side surface of each projection and the curved land surface-forming portion can be a reference boundary point, and the reference boundary point can be located inward of a reference forming surface of the tread-forming surface.

Tire mold and production method for tire using a tire mold

A tyre includes a tread portion provided with circumferentially extending main grooves and land portions. The main grooves include an outboard crown main groove, and an inboard crown main groove. The land portions include a crown land portion defined between the outboard crown main groove and the inboard crown main groove. The crown land portion is provided with first crown sipes having first ends connected to the outboard crown main groove and second ends terminating within the crown land portion, and second crown sipes having first ends connected to the inboard crown main groove and second ends terminating within the crown land portion, wherein the first crown sipes are inclined with respect to a tyre axial direction in a same direction as the second crown sipes, and the first crown sipes and the second crown sipes are different in angle with respect to the tyre axial direction.

Tyre

A tire comprises a tread portion. The tread portioncomprises two crown land regionsand two shoulder land regionsdivided by a crown main grooveand a pair of shoulder main groovesandarranged one by one on each side of the crown main groove. Each of the two crown land regionsis provided with a plurality of sipeseach having a width less than 1.5 mm. The sipesof each of the two crown land regionsinclude only semi-open sipeseach having one end connected with one of the main grooves and the other end terminating within the land region. The sipesof the two crown land regionsare inclined in a same direction with respect to a tire axial direction.

Tire

Growing community of inventors

Kobe, Japan

Rena Onitsuka