A pneumatic tire includes a bead portions and a bead core at the bead portions, the tire being mounted to a 15°-tapered specified rim. The bead portions include a portion inward in a radial direction of an extension line of an inner circumferential surface of the bead core, the extension line extending in the lateral direction, that is positioned outward in the tire lateral direction of an imaginary line passing through a first intersection point between the extension line and a tire inner surface and extends inward in the tire radial direction from the extension line at an angle perpendicular to the extension line. An angle α formed by the imaginary line and a line segment passing through a second intersection point between a bead base and the tire inner surface and the first intersection point between the extension line and the tire inner surface is from 0° to 25°.

A pneumatic tire 1 comprises an annular bead core 5 embedded in each bead portion 4 of the tire. The bead core 5 is composed of a plurality of wire rings 10 each of which is made of a spirally overlap-wound bead wire 11 and which are arranged in the tire axial direction. The wire rings 11 include a first ring 13 whose bead wire 11 is a twisted cord 13a made of a plurality of filaments 15 twisted together, and a second ring 14 whose bead wire 11 is a monofilament cord 14a made of a single filament.

Disclosed is a pneumatic tire with a bead having enhanced endurance, more particularly, a pneumatic tire with a bead having enhanced stiffness in which at least one bead core is provided and a carcass does not have a turn-up structure at an end thereof such that stiffness of the bead and sidewall is enhanced. The pneumatic tire includes bead cores in which multi-layered bead wire cords are coiled, bead fillers adhering to the bead cores having at least two rows, and a carcass ply disposed between the bead cores of the bead fillers, the carcass ply having a linear shape without a turn-up structure, wherein a left bead filler and a right bead filler including the bead cores including the bead wire cords are disposed at both sides of the carcass ply, and each of the left and right bead fillers has a diameter decreasing upward from a bead base.

A pneumatic tire is provided. In a meridian cross-section, an external contour shape of the bead core is a polygon formed by common tangent lines of a plurality of circumferential portions of a bead wire, the external contour shape includes a single vertex located toward the outside in a tire radial direction, an internal angle formed by two sides sandwiching the vertex is an acute angle, a bottom side of the external contour shape is inclined with respect to the tire lateral direction by from 2° to 9°, and the carcass layer is bent and folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from a position of an outer end of the bead core in the tire radial direction extends toward a sidewall portion in contact with a body portion.

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.

In a cross-section of a pneumatic tire, a contour of the bead core is a polygon formed by tangent lines of circumferential portions of a bead wire, the contour includes a vertex with an acute angle and a bottom side opposite the vertex, the carcass layer is folded back along a circumference of the bead core in a bead portion, a folded back portion of the carcass layer from an outer end of the bead core extends in the radial direction, and a distance in the radial direction between a center of an arc profile of a tire outer surface and a straight line extending in the lateral direction through the vertex is within 20% of a radius r of the arc, and a distance in the lateral direction between the center of the arc and a straight line extending in the radial direction through the vertex is within 2r±0.4r.

Provided is a pneumatic radial tire for an aircraft including a bead core, a radial carcass and a stiffener, the radial carcass including one or more turn-up plies and one or more down plies, wherein in tire axial direction cross-sectional view, when an intersection point of a virtual circle with a ply closest to a tire axial direction inner side of the stiffener among the plies intersecting with the virtual circle having a radius that is twice as large as a diameter D of the bead core from a center O of the bead core is a point A, an intersection point of the virtual circle with a ply closest to a tire axial direction outer side of the stiffener is a point B, and a midpoint between the point A and the point B is a reference point C, then a line segment OC connecting the center O of the bead core to the reference point C has an inclination angle θ of 17° or less to a tire radial direction line passing the center O of the bead core on the tire axial direction outer side.

A tire having no ply turnup is described. The tire includes a tread, a single layer of ply, a first triangular shaped bead and a second triangular shaped bead, wherein the radially inner end of the single layer of ply is secured between the first bead and the second bead.

A tire having no ply turnup is described. The tire includes a tread, a single layer of ply, and a first triangular shaped bead, wherein the radially inner end of the single layer of ply is secured between the first bead and a second bead, wherein the second bead is formed by spirally winding a strip of reinforcements onto the radially inner end of the ply, wherein the strip is formed of two or more parallel reinforcements.

A foldable tire includes a tire main body provided at two edges thereof with two tire beads respectively. A plurality of rings are disposed in each of the tire beads. Each of the rings has a reinforcing core, which includes a plurality of flexible steel filaments helically entwined with each other and has a diameter ranging from 0.2 millimeters to 0.5 millimeters, and a cladding layer clothing the reinforcing core, so that the reinforcing cores located in each of the tire beads are separated from each other.