Sumitomo Rubber Industries Limited

The Goodyear & Tire Rubber Company

Tadao Matsumoto

Saburo Miyabe

Nobuaki Minami

Helmut Wolfgang Fehl

Christian Windisch

Naoki Yukawa

Naohiko Kikuchi

Chieko Aoki

Hiroaki Ninomiya

Fumikazu Yamashita

Yasutaka Iwata

Toru Fukumoto

Yasuaki Kuniyasu

Kentaro Yagyu

Maiko Okada

Wako Iwamura

Shingo Umekita

A tyre includes a tread portion being provided with at least one main groove extending in a tyre circumferential direction and at least one lateral groove connected to the at least one main groove. The at least one main groove includes an intersection to which the lateral groove is connected. One of groove walls of the at least one main groove or the at least one lateral groove is provided with projections protruding toward the intersection.

Tyre

A pneumatic tirecomprises a sidewall portion. The sidewall portioncomprises an outer surface () provided with a plurality of protruding portionsprotruding outwardly in a tire axial direction and arranged in a tire circumferential direction. Each of the protruding portionscomprises a pair of side surfacesextending in a tire radial direction at both ends in a tire circumferential direction of each of the protruding portionsand a top surfacearranged outermost in the tire axial direction between the pair of the side surfaces. In at least one of the protruding portions, the top surfaceis provided with at least one groove

Pneumatic tire

A pneumatic tire with a pair of sidewall portions, which comprises at least one of said sidewall portions with a radially outer region being radially outside than a tire maximum width position of its outer surface, the radially outer region being provided with a serration pattern, the serration pattern comprising a first serration group and a second serration group, the first serration group comprising a plurality of concentrically arranged first arc-shaped ridges at regular intervals around a first center point O, the second serration group comprising a plurality of concentrically arranged second arc-shaped ridges at regular intervals around a second center point Othat is located radially outside than the first center point Oof the first serration group, and the first serration group and second serration group arranged in a circumferential direction of the tire so as to overlap partially.

In the tire, fillersare layered over clinchesin portions outward of a carcassin the axial direction. A carcass plyis turned up around cores. Turned-up portionsare disposed between the fillersand apexes. Each clinchhas a maximum thickness Tcx that is measured along a line normal to an inner surface, in the axial direction, of the clinch. A ratio of a thickness Tfof the fillerto a sum of the thickness Tfand the thickness Tcx is greater than or equal to 0.1 and not greater than 0.6. A percentage of a complex elastic modulus E*f of the fillerrelative to a complex elastic modulus E*a of the apexis greater than or equal to 70% and not greater than 125%.

A pneumatic tireincludes a pair of beadsand a carcassextending on and between both beads. Each beadincludes a core. The coreincludes: a main bodyincluding a cordextending in a circumferential direction; and a stretchable portionformed from a crosslinked rubber. The stretchable portionis located inward of the main bodyin an axial direction. The stretchable portionhas a size with which at least one cross-section of the cordcan be included therein in a cross-section of the bead. Preferably, in the tire, the main bodyincludes a hard unit and a soft unit. The soft unit is located outward of the hard unit in a radial direction. A hard cord of the hard unit stretches more easily than a soft cord of the soft unit.

Pneumatic tire having bead core with stretchable portion

A pneumatic tire is provided in the outer surface of each sidewall portion with a serrated zone formed by a number of serration grooves extending at an angle of at most 45 degrees with respect to the tire radial direction. Each of the serration grooves has a variable depth such that the deepest point lies between the radially outermost end and innermost end of the serration groove. The deepest point is positioned in a range between 0.2 time and 0.4 times a radial distance Ha from the maximum carcass section width position to the radially outermost end of the tire. As a result, the rolling resistance of the tire can be reduced.

A tire having an asymmetric tread pattern that land proportion of outer side areais larger than inner side area, but having a reduced difference in drainage performance between tires on right and left wheels, the tire having tread surfacedivided by four circumferential groovesandinto center land, middle landsand shoulder lands, wherein middle landand shoulder landin the outer side areaare divided respectively by outer middle lateral groovesand outer shoulder lateral groovesinto blocksand blocks, inclination direction of the middle lateral groovesis opposite to that of the shoulder lateral grooveswith respect to tire axial direction, and the lateral groovesandare inclined at an angle &#x3b8;mo between 5&#xb0; and 45&#xb0; and at an angle &#x3b8;so between more than 0&#xb0; and not more than 40&#xb0;, respectively.

Pneumatic tire with asymmetric tread pattern

A pneumatic tire including a longitudinal main groove formed concavely on a tread surface thereof in a radial direction thereof by extending the longitudinal main groove linearly in a circumferential direction thereof; and narrow grooves formed concavely on at least an outer side surface of both side surfaces of the longitudinal main groove opposed to each other in a widthwise direction of the pneumatic tire by spacing the narrow grooves at certain intervals in a circumferential direction of the pneumatic tire. Each of the narrow grooves is so configured that a longer side of each of the narrow grooves extends in the radial direction of the pneumatic tire and that a shorter side of each of the narrow grooves extends in the circumferential direction of the pneumatic tire. A sectional configuration of a position having a maximum sectional area in each of the narrow grooves is circular arc-shaped.

Pneumatic tire having narrow grooves in side surface of longitudinal main groove

A tread surfaceis divided by inner and outer longitudinal groovesandlocated on opposite sides of the tire equator into a central land portion, intermediate land portionsand shoulder land portions. The intermediate land portionincludes an inclined grooveshaving an angle &#x3b8; with respect to the circumferential direction of the tire, and the angle is increased from an inner end (mi) away from the inner longitudinal groovesby a small distance La to an outer end (mo) where the intermediate land portion intersects with the outer longitudinal grooves. An angle &#x3b8;i in the inner end (mi) is 0 to 25&#xb0;, and an angle &#x3b8;o in the outer end (mo) is 60 to 80&#xb0;. A pitch Pof the inclined groovesin the circumferential direction is greater than a pitch Pof lug groovesprovided in the shoulder land portionin the circumferential direction.

Pneumatic tire with tread having continuous ribs and block rows

A tire noise reducing system comprises a pneumatic tire with a hollow, a wheel rim on which the tire is mounted so that said hollow forms a closed cavity, and a noise damper disposed in the closed cavity, wherein the noise damper is formed by fixing a strip of a porous material to the tire or wheel rim, the noise damper has a volume in a range of from 0.4 to 20% of the volume of the cavity, the noise damper has a sectional shape substantially constant in the tire circumferential direction, and the pneumatic tire comprises a tread portion provided with tread grooves defining a tread pattern having a sea ratio of 20 to 35%.

Tire noise reducing system

A tire comprises a sidewall provided with a mark region for displaying at least one mark including at least one of a sold mark and an outline mark, the mark region is provided with serration made up of serration slots and ridges which are drawn up in lines, the mark is formed by discontinuous parts of the serration, wherein the discontinuous parts of the serration are (1) discontinuous parts of serration slots only or (2) discontinuous parts of ridges only or (3) discontinuous parts of serration slots and discontinuous parts of ridges, wherein the discontinuous part of the serration slot is a shallow part formed within the serration slot and having a top face extending across a corresponding part of the mark in substantially parallel with a tire sidewall surface.

Vehicle tire

A pneumatic tire comprises a tread portion provided with at least one wide circumferential groove, the wide circumferential groove extending continuously in the tire circumferential direction and having a groove width GW of not less than 5% of the ground contacting width TW, the wide circumferential groove provided in the groove bottom with a groove bottom rib, the groove bottom rib extending continuously along the overall length of the wide circumferential groove, the groove bottom rib having a height Hr in a range of from 0.5 to 3.0 mm and a base width Wr in a range of from 10 to 30% of the groove width GW, and the groove bottom rib provided in the top face with a small groove having a depth Dr of less than the height Hr.

Pneumatic tire including groove bottom rib

A pneumatic tire comprises a tread portion provided with at least one longitudinal groove extending in the tire circumferential direction and blocks adjacent to one side of the at least one longitudinal groove, each of the blocks being provided with a cut-slope on a corner between the block's top surface and a lateral face facing the longitudinal groove, the cut-slope inclining towards the bottom of the longitudinal groove, and the axial width of the cut-slope gradually decreasing from a middle point of the cut-slope towards each side thereof in the circumferential direction, whereby the vehicle overturn marginal during high speed running is improved.

Growing community of inventors

Kobe, Japan

Tadao Matsumoto