Pneumatic tire

Patent metadata

Field	Value
Publication number	US-9944128-B2
Application number	US-201414781640-A
Country	US
Kind code	B2
Filing date	Apr 1, 2014
Priority date	Apr 3, 2013
Publication date	Apr 17, 2018
Grant date	Apr 17, 2018

Abstract

A pneumatic tire including: on a tread of the tire, inclined belt layer and circumferential belt layer; and on the tread surface, a plurality of circumferential grooves extending in the tread circumferential direction, and shoulder land portions partitioned between the circumferential grooves located outermost in the tire width direction and tread ground contact ends. Positions of the tread surface that correspond to the outermost ends of the circumferential belt layer in the tire width direction are within the shoulder land portions, and the distance in the tire width direction between the outermost ends in the tire width direction of the circumferential belt layer and tire equator side ends of the shoulder land portions is 12% or more and 22% or less of a half of the width of the circumferential belt layer in tire width direction.

First claim

The invention claimed is:

1. A pneumatic tire comprising:
on a tread of the tire, at least one inclined belt layer obtained by rubber-coating a plurality of cords that are extended and inclined with respect to the tread circumferential direction and are arranged parallel to one another, and at least one circumferential belt layer obtained by rubber-coating a plurality of cords that are extended in the tread circumferential direction and are arranged parallel to one another, the at least one circumferential belt layer being located on the inner side of the at least one inclined belt layer in the tire radial direction; and
on the tread surface, a plurality of circumferential grooves extending in the tread circumferential direction, and shoulder land portions partitioned between the circumferential grooves located outermost in the tire width direction and tread ground contact ends,
wherein positions of the tread surface that correspond to the outermost ends of the at least one circumferential belt layer in the tire width direction are within the shoulder land portions, and the distance in the tire width direction between the outermost ends in the tire width direction of the at least one circumferential belt layer and tire equator side ends of the shoulder land portions is 12% or more and 22% or less of a half of the width of the at least one circumferential belt layer in tire width direction; and
wherein the outermost ends of the at least one circumferential belt layer in the tire width direction are located between widthwise center points of the shoulder land portions and the tread ground contact ends.

2. The pneumatic tire according to claim 1 , wherein the distance between the tread ground contact ends and the rotation axis of the tire is smaller than the distance between the tire equator and the rotation axis of the tire by more than 0% and 1.5% or less.

3. The pneumatic tire according to claim 1 , further comprising land portions partitioned between the circumferential grooves,
wherein in the cross section in the tire width direction, the angle of inclination of groove walls on the outer sides in the tire width direction of the circumferential grooves located outermost in the tire width direction with respect to imaginary lines extending through the tire equator side ends of the shoulder land portions and intersecting the tread surface at right angles is larger than the angle of inclination of groove walls on the tire equator sides of the circumferential grooves located outermost in the tire width direction with respect to imaginary lines extending through outer ends in the tire width direction of the land portions adjacent to the shoulder land portions in the tire width direction and intersecting the tread surface at right angles.

4. The pneumatic tire according to claim 1 , wherein tire equator side portions of the shoulder land portions are each provided with an inclined surface that gradually reduces the height of the shoulder land portions from the outer sides in the tire width direction toward the circumferential grooves located outermost in the tire width direction and continuously extends to the groove walls on the outer side in the tire width direction of the circumferential grooves located outermost in the tire width direction.

5. The pneumatic tire according to claim 1 ,
wherein rubber members arranged at the tire equator side portions of the shoulder land portions have a lower compressive modulus as compared with rubber members arranged on the outer sides in the tire width direction of the rubber members of the shoulder land portions, and the boundaries between the rubber members are flat or curved surfaces extended and inclined with respect to a plane parallel to the tire equatorial plane and the thickness of the rubber members arranged at the tire equator side portions of the shoulder land portions gradually increases from the outer side in the tire width direction toward the circumferential grooves.

6. The pneumatic tire according to claim 1 , comprising
wherein the at least one inclined belt layer consists of two inclined belt layers, and
wherein the at least one circumferential belt layer consists of a single circumferential belt layer.

Assignees

• Bridgestone Corp

Inventors

• Okazaki Naoto

Classifications

• B60C11/01

  Shape of the shoulders between tread and sidewall, e.g. rounded, stepped or cantilevered · CPC title

• B60C2009/2012

  with particular configuration of the belt cords in the respective belt layers · CPC title

• B60C11/1307

  with special features of the groove walls · CPC title

• B60C9/2009 Primary

  comprising plies of different materials · CPC title

• B60C2009/2019

  comprising cords at an angle of 30 to 60 degrees to the circumferential direction · CPC title