Provided is a pneumatic tire having laminated reinforcement layers with organic fiber over a polygonal cross-section bead core, and in the layer, a rubber-coated organic fiber cord is tilted to the center line of the bead core in a transverse section and is spirally coiled, in which each organic fiber cord in an inner and outer adjacent reinforcement layers over the bead core extends such that an organic fiber cord in the inner reinforcement layer and an organic fiber cord in the outer reinforcement layer intersect each other relative to the center line of the bead core in the transverse section, in which in the inner reinforcement layer, the cord is coiled with space at least partially in a tire circumferential direction such that the cord does not overlap in the tire circumferential direction, and the outer reinforcement layer is arranged to cover at least a part of the space.

A tire for a heavy vehicle with a radial carcass reinforcement anchored in two beads by wrapping around bead wires. In a radial plane, radially on the inside of the radially innermost point of the at least one layer of carcass reinforcement and axially on the outside of the geometric center of the bead wire, the radius of curvature at a point on the exterior surface of the bead is greater than the radius of curvature at the point of orthogonal projection of the point of the exterior surface of the bead onto the at least one layer of carcass reinforcement.

Provided is a pneumatic tire including a carcass constituted of at least one ply including a ply main body and ply turn-up portions, and a recessed portion formed to be recessed inward in the tire axial direction at an outer surface of the tire in a region between a rim separating point and the tire maximum width position in each sidewall portion. In a section taken along the tire axial direction in a non-rim assembled state, an angle is defined as an angle that an outer surface straight line defined by each bead back face portion passing the first intersection and the second intersection forms with respect to the tire axial direction, and the angle is in the range from 70 to 100.

The invention relates to improving the endurance of a bead of a radial tire for a heavy vehicle of construction plant type by reducing the compression to which the turn-up is subjected when the tire is driven on. According to the invention, for a tire for a heavy vehicle of construction plant type comprising two beads intended to come into contact with a rim having two rim flanges, a carcass reinforcement comprising at least one carcass reinforcement layer having a main part wrapped, within each bead, from the inside towards the outside of the tire, around a bead wire of substantially circular meridian section, to form a turn-up, a filling element extending the bead wire radially towards the outside and axially separating the main part and the turn-up, the distance (d) between a first segment of turn-up and the main part decreasing continuously, radially towards the outside, from the bead wire as far as a minimum distance (d.sub.1), the distance (d.sub.2) between a second segment of turn-up, extending the first segment of turn-up radially towards the outside, and the main part is substantially constant and equal to the minimum distance (d.sub.1) between the first segment of turn-up and the main part.

Provided are: a tire mold including a bead portion molding surface for molding the bead portion of the tire, the bead portion molding surface having a ridge molding part including a recessed groove extending in the mold radial direction, the ridge molding part being formed in a flange contact portion molding region for molding a rim-flange contact portion of the tire; and a pneumatic tire, in which a bead filler has the tire radial direction outer end positioned more inward in the tire radial direction relative to the rim line position, and a ridge forming portion including a ridge extending in the tire radial direction is formed on the outer surface of the bead portion, the ridge forming portion being positioned in the rim flange contact portion.

A pneumatic radial tire includes a bead filler, a carcass ply, a steel protection layer, and an organic fiber protection layer. A reinforcing rubber sandwiches a wind-up end of the steel protection layer. A relationship of 1A/B2 is satisfied between a width A from the wind-up end of the steel protection layer to a tire inner surface, and a width B from the wind-up end of the steel protection layer to a tire outer surface. The wind-up end of the carcass ply is covered with a ply cover member. A relationship of 0.8D/C1.2 is satisfied between a thickness C of a second bead filler positioning between the ply cover member and a first bead filler, and a thickness D of the reinforcing rubber positioning between the ply cover member and the steel protection layer.

A pneumatic tire includes an elastomeric casing. The elastomeric casing includes a crown portion, opposing sidewalls, and bead areas that are formed along the sidewalls in spaced relation to the crown portion. The bead areas include at least one bead reinforcing element, such as a bead core and/or a bead filler, that is at least partially formed from carbon fibers. A method of manufacturing a pneumatic tire assembly is also included.

A heavy duty pneumatic tire includes a clinch portion extending from the sidewalls to the beads. A concave curved surface extends on an outer surface of the clinch portion in a circumferential direction. A convex curved surface is engageable with the concave curved surface. A ratio R1/R2 of a radius of curvature of the concave curved surface to a radius of curvature of the convex curved surface, satisfies 1.7R1/R23.9, a ratio D1/R2 of a depth of the concave curved surface to the radius of curvature of the convex curved surface satisfies 0.05D1/R20.09, and the radius of curvature R1 of the concave curved surface and the radius of curvature R2 of the convex curved surface are each a radius of curvature of an arc on a cross section as taken along a plane including a center axis of the tire.

A pneumatic tire according to the invention includes: a pair of left and right beads 3 each including a bead cores 3a and bead fillers 3b; a carcass ply 5 extended around the bead cores 3a; and an inner liner 4 arranged on an inner peripheral side of the carcass ply 5, and is characterized in that the carcass ply 5 is wound up around the bead cores 3a from the outside in the direction of width of tire to the inside in the direction of width of tire, and a distortion restraining layer 7 configured to restrain distortion of the winding ends 5a of the carcass ply 5 is provided between the bead fillers 3b and the carcass ply 5 so as to overlap with a wind-up ends 5a of the carcass ply 5.

A covered cord is formed by covering a cord with a resin material, and a covered bead is formed by welding or adhering together the resin material of the covered cord whilst shaping into a bead shape, such that resin material fills between the cord. The covered bead is placed in contact with a jig disposed inside a cavity of a tire mold for molding a tire frame member, the covered bead is fixed inside the mold, and the tire frame member is molded containing the covered bead in a tire bead portion by pouring molten resin material into the cavity.