Patent classifications
B60C15/0054
Tire having specified carcass reinforcement for a two-wheeled vehicle
A tire for a two-wheeled motorized vehicle includes a tread joined by two sidewalls to two beads, the tread having first and second elastomer compositions, crown reinforcement, radially inside tread having a crown layer having mutually parallel circumferential reinforcers forming an angle at most equal to 5° to the circumferential direction, a carcass reinforcement, radially inside crown reinforcement, having turnup. Carcass reinforcement includes mutually parallel reinforcers, and wrapped, in each bead, from the inside to the outside of the tire, about bead wire in order to form turnup having free end E.sub.2. Carcass reinforcement includes crown portion and lateral portion, crown portion extending axially between first and second ends E.sub.2, E′.sub.2, E.sub.2 and E′.sub.2 being symmetric to equatorial plane P of the tire, lateral portion extending symmetrically to equatorial plane P radially towards the inside, from radially outermost end E.sub.2 to fourth end E.sub.4 disposed at the bead wire.
PNEUMATIC TIRE
In this pneumatic tire, a tan δ value T20 of a rubber member, which constitutes at least one of a bead filler, an undertread, a sidewall rubber, and a rim cushion rubber, at 20° C. and a tan δ value T60 of the rubber member at 60° C. satisfy 0.50≤T20/T60≤2.00 and T20≤0.22. Additionally, the tan δ value T20 of the rubber member at 20° C. is in a range T20≤0.15. Additionally, a tan δ value T20_sw of the sidewall rubber at 20° C. and a tan δ value T60_sw of the sidewall rubber at 60° C. satisfy 0.50≤T20_sw/T60_sw≤1.50 and T20_sw≤0.11.
Pneumatic tire
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 φ of the bead wire have a relationship 2.0≤Wh/φ≤15.0. A radial height H2 of a contact portion between a body portion and a turned back portion of a carcass layer has a relationship 0.80≤H2/H1≤3.00 to a radial height H1 of the bead cores.
Pneumatic tire
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%.
TIRE
A bead portion of a pneumatic tire includes an annular bead structure in which a core part in which a bead core is covered with a resin, and a bead filler which is formed of a resin, are integrally formed. A plurality of concave portions and a plurality of convex portions are formed on a surface of the bead structure. Each of the concave portions is extended to and communicated with a tire radial direction outside end of the bead structure.
TIRE
The tire has s bead structure including a bead core portion having a cord unit and a bead filler portion continuous to the bead core portion in the tire radial direction outside of the bead core portion and formed of a resin material. The bead filler portion has a tip portion which becomes thinner toward outside in the tire radial direction. The tip portion is positioned inside in the tire width direction inside than a straight line passing through a center in the width direction at an inside end in the tire radial direction of the bead core portion and passing through a center in the width direction at outside end in the tire radial direction of the bead core portion.
RUN-FLAT TIRE
A bead portion of a run-flat tire includes a bead core portion having a bead cord, a first bead filler portion continuous to the bead core portion and provided outside in the tire radial direction of the bead core portion, and a second bead filler portion provided outside in the tire width direction of the first bead filler portion via a carcass ply. The second bead filler portion is formed of a resin material.
Pneumatic tire
In a tire 2, a length from a center in an axial direction of a boundary between a core 30 and an apex 32 of each bead 10 to an outer end PA of the apex 32 is not less than 10 mm and not greater than 15 mm. In a state where the tire 2 is mounted on a normal rim and an internal pressure of the tire 2 is adjusted to a normal internal pressure, a shape of a main body portion 36, of a carcass ply 34, which is located in a zone from a boundary portion between a tread 4 and each sidewall 6 to the outer end PA of each apex 32 is represented by a single circular arc, and a diameter of the circular arc is not less than 75% and not greater than 90% of a cross-sectional height of a carcass 14.
Tire
Provided is a tire including a tread portion. The tread portion includes two circumferential grooves and three land portions. The three land portions include a crown land portion disposed on a tire equator, and two shoulder land portions including tread contact ends. At least one of the shoulder land portions includes a plurality of main inclined grooves and a plurality of subsidiary inclined grooves. The main inclined grooves have tire-axially inner ends ending in the shoulder land portions and tire-axially outer ends disposed outwardly of the tread contact ends Te in the tire axial direction. The subsidiary inclined grooves have tire-axially inner ends ending in the shoulder land portions and tire-axially outer ends ending in the shoulder land portions.
TYRE AND A METHOD FOR MANUFACTURING AN ANNULAR
A method for manufacturing an annular carcass of a tire includes providing first and second ply materials, each including cords; winding at least a layer of the first ply material and a layer of the second ply material onto a carcass drum so the first ply material radially surrounds the second ply material; arranging two cables onto the cylindrical carcass preform; turning the part of the cylindrical carcass preform about the closer cable onto the part of the cylindrical carcass preform between the two cables; and expanding the cylindrical carcass preform to form an annular carcass having, in a bead area, inner and outer layers of the first ply material and inner and outer layers of the second ply material. The ply materials are arranged so the cords thereof are arranged cross-wise with respect to its neighboring ply materials or a neighboring ply material, considering the innermost or outermost layer.