Run-flat radial tire

Patent metadata

Field	Value
Publication number	US-10464378-B2
Application number	US-201515129083-A
Country	US
Kind code	B2
Filing date	Feb 19, 2015
Priority date	Apr 4, 2014
Publication date	Nov 5, 2019
Grant date	Nov 5, 2019

Abstract

A run-flat radial tire having a tire cross-section height of 115 mm or greater including: a carcass spanning between a pair of bead portions; a vehicle mounting direction outer side side-reinforcing rubber layer that is provided to a tire side portion at a vehicle mounting direction outer side and that extends in a tire radial direction along an inner face of the carcass; and a vehicle mounting direction inner side side-reinforcing rubber layer that is provided to a tire side portion at a vehicle mounting direction inner side and that extends in the tire radial direction along an inner face of the carcass, a tire radial direction outer side end portion of the vehicle mounting direction inner side side-reinforcing rubber layer being closer to a tire equatorial plane than a tire radial direction outer side end portion of the vehicle mounting direction outer side side-reinforcing rubber layer.

First claim

The invention claimed is:

1. A run-flat radial tire comprising:
a carcass spanning between a pair of bead portions;
a vehicle mounting direction outer side side-reinforcing rubber layer that is provided at a tire side portion at a vehicle mounting direction outer side and that extends in a tire radial direction along an inner face of the carcass;
a vehicle mounting direction inner side side-reinforcing rubber layer that is provided at a tire side portion at a vehicle mounting direction inner side and that extends in the tire radial direction along an inner face of the carcass, a tire radial direction outer side end portion, which contacts with the carcass and that is a closest portion to a tire equatorial plane, of the vehicle mounting direction inner side side-reinforcing rubber layer being closer to the tire equatorial plane than a tire radial direction outer side end portion, which contacts with the carcass that is a closest portion to the tire equatorial plane, of the vehicle mounting direction outer side side-reinforcing rubber layer; and
a tire tread portion that connects the tire side portion at the vehicle mounting direction inner side and the tire side portion of the vehicle mounting direction outer side, wherein:
a tire cross-section height of the run-flat radial tire is 115 mm or more than 115 mm, and
the tire radial direction outer side end portion of the vehicle mounting direction inner side side-reinforcing rubber layer and a circumferential direction groove that is innermost in the vehicle mounting direction among circumferential direction grooves that are formed on the tire tread portion are overlapped in the tire radial direction.

2. The run-flat radial tire of claim 1 , further comprising:
a maximum width inclined belt layer that is provided at the tire tread portion at a tire radial direction outer side of the carcass, that includes a cord extending in a direction inclined with respect to a tire circumferential direction, and that is a belt layer having a largest width in a tire axial direction, wherein
a ratio L 2 /L 1 , of an overlap width L 1 in the tire axial direction between the maximum width inclined belt layer and the vehicle mounting direction outer side side-reinforcing rubber layer and an overlap width L 2 in the tire axial direction between the maximum width inclined belt layer and the vehicle mounting direction inner side side-reinforcing rubber layer, is set to 15/14 or greater.

3. The run-flat radial tire of claim 1 , further comprising:
a maximum width inclined belt layer that is provided at the tire tread portion at a tire radial direction outer side of the carcass, that includes a cord extending in a direction inclined with respect to a tire circumferential direction, and that is a belt layer having a largest width in a tire axial direction, wherein
an overlap width L 1 in the tire axial direction between the maximum width inclined belt layer and the vehicle mounting direction outer side side-reinforcing rubber layer, and an overlap width L 2 in the tire axial direction between the maximum width inclined belt layer and the vehicle mounting direction inner side side-reinforcing rubber layer are each 15% or more than 15% of the tire axial direction width of the maximum width inclined belt layer.

4. The run-flat radial tire of claim 1 , further comprising:
a maximum width inclined belt layer that is provided at the tire tread portion at a tire radial direction outer side of the carcass, that includes a cord extending in a direction inclined with respect to a tire circumferential direction, and that is a belt layer having a largest width in a tire axial direction, wherein
an overlap width L 1 in the tire axial direction between the maximum width inclined belt layer and the vehicle mounting direction outer side side-reinforcing rubber layer is from 5% to 14% of the tire axial direction width of the maximum width inclined belt layer, and an overlap width L 2 in the tire axial direction between the maximum width inclined belt layer and the vehicle mounting direction inner side side-reinforcing rubber layer is from 5% to 40% of the tire axial direction width of the maximum width inclined belt layer.

Assignees

• Bridgestone Corp

Inventors

• Yokoyama Masafumi

Classifications

• B60C15/06

  Flipper strips, fillers, or chafing strips {and reinforcing layers for the construction of the bead} · CPC title

• B60C3/04

  characterised by the relative dimensions of the section, e.g. low profile (B60C3/06 takes precedence) · CPC title

• B60C17/0009 Primary

  comprising sidewall rubber inserts, e.g. crescent shaped inserts · CPC title

• B60C2017/0072

  Thickness · CPC title

• B60C3/06

  asymmetric · CPC title