The Yokohama Rubber Co., Ltd.

Hiraku Koda

Atsushi Tanno

Jun Matsuda

Yuki Sasaya

Ryohei Takemori

Masaaki Nagayasu

Takahisa Murata

Masatoshi Shimizu

Provided is a tire having a cross-sectional height (SH) ranging from 50 mm to 150 mm, in an unloaded state where the tire is mounted on a specified rim and inflated to a specified internal pressure, an opening distance (A) between the tire and a rim flange on a perpendicular line drawn from an outermost point of the rim flange in a radial direction to an outer surface of the tire with respect to the cross-sectional height (SH) satisfies a relationship 0.01≤A/SH≤0.16 and a projection amount (W) corresponding to one half of a difference between a total width of the tire and a rim width of the specified rim satisfy a relationship 0.03≤A/W≤1.60.

Tire

In a pneumatic tire, a turned back portion of a carcass layer contacts a body portion of the carcass layer in a cross-sectional view in a tire meridian direction to form a closed region surrounding bead cores. A rubber occupancy ratio in the closed region is in a range of 15% or less. The bead cores have a predetermined wire arrangement structure formed by arranging wire cross sections of bead wires in the cross-sectional view in the tire meridian direction. Additionally, a self-contact height (CH) of the carcass layer and a circumferential length (L) of the wire arrangement have a relationship 1.0≤CH/L≤10.0.

Pneumatic tire

Provided is a pneumatic tire with wet steering stability performance and dry steering stability performance enhanced in a well-balanced manner. A dimple group is composed of a plurality of dimples (to) disposed at intervals and aligned in a tire circumferential direction. When the minimum center-to-center distance between different dimples () in an identical dimple group is defined as K and the minimum center-to-center distance between dimples () in different dimple groups is defined as L, the ratio L/K is 3.5 or more and 10.0 or less and the minimum center-to-center distance L is 20 mm or more and equal to or less than a ground contact length.

A pneumatic tire includes protrusion portions formed on at least one tire side portion of tire side portions located on both sides in a width direction, projecting from a tire side surface that is a surface of the tire side portion, and extending along the tire side surface, the protrusion portions having an angle α within a range of no less than 6% and no more than 50% of an angle of one round in a circumferential direction, the angle α being relative and in the circumferential direction between two protrusion portion end position lines that respectively extend in a radial direction through different end portions of both end portions in an extending direction of the protrusion portions, and the tire side portion having a thickness at a tire maximum width position within a range of no less than 2 mm and no more than 9 mm.

Provided is a pneumatic tire. At least one land portion is defined and formed by a plurality of circumferential main grooves provided in a tread surface. A main sipe including a body portion and a chamfered portion is formed in at least one side of the body portion. A branch sipe branching from the chamfered portion is provided. The depth of the body portion is equal to or greater than the depth of the branch sipe.

In this pneumatic tire, the bead core has a predetermined wire array structure obtained by arranging wire cross-sections of bead wires in a cross-sectional view in a tire meridian direction. The following are defined in the wire array structure: a tangent line that contacts, from the side of a rim fitting face, an innermost layer in the tire radial direction and the wire cross-section on the innermost side and the outermost side in the tire lateral direction; contact points of the tangent line with respect to the wire cross-sections on the innermost side and the outermost side; a middle point of the contact points; and gauges in the tire radial direction from the contact points and middle point to the rim fitting face. In this case, the change rates of the gauges before and after rim assembly each are in the range of 10% to 60%.

In a pneumatic tire, bead cores have a wire arrangement. In a cross-sectional view in a tire meridian direction, a tangential line and a contact point are defined. The tangential line contacts an innermost layer in a radial direction and the wire cross sections innermost and outermost in a lateral direction in the wire arrangement from a rim fitting surface side. The contact point of the tangent line is on the wire cross section on the outermost side. A gauge Wh in the lateral direction from the contact point to the rim fitting surface and an outer diameter &#x3c6; of the bead wire have a relationship 2.0&#x2264;Wh/&#x3c6;&#x2264;15.0. A radial height Hof a contact portion between a body portion and a turned back portion of a carcass layer has a relationship 0.80&#x2264;H/H&#x2264;3.00 to a radial height Hof the bead cores.

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Hiratsuka, Japan

Hiraku Koda