A chafer of a heavy load tire is arranged between a bead core and a carcass and is formed by an organic fiber. As a distance L1 is defined by a linear distance between a bead innermost portion, which is a portion of the bead core at an innermost side in the tire width direction, and an outer end in a tire radial direction of the chafer, and a distance L2 is defined by a linear distance between the bead innermost portion and a carcass outermost portion, which is a portion of a carcass body portion at an outermost side in the tire width direction, L1/L25/12 is fulfilled.

A heavy-duty pneumatic tire includes a carcass ply including a main portion extending between bead cores and a pair of turn-up portions, a first reinforcing layer of a steel cord disposed in each bead portion in a U-shaped manner, and a second reinforcing layer of an organic fiber cord disposed in each bead portion and at least a part of the second reinforcing layer extending in a radial direction of the tire at an axially outward location of the first reinforcing layer. The second reinforcing layer includes an axially inner second ply and an outer second ply. The outer second ply has an inner end positioned below the bead core. The inner second ply has an inner end located axially inward of the inner end of the outer second ply, and has a substantially same length as the outer second ply in a tire cross-section.

Disclosed is a tubeless tire having a reinforced bead portion capable of reducing the stress applied to a portion contacting a rim flange and to an edge of a carcass. The tubeless tire includes a carcass turned up around a bead core, a bead filler filled in a space above the bead core surrounded by the carcass, a steel chafer disposed to contact an outer surface of the carcass, and a first reinforcing rubber layer provided between the bead core and the carcass in order to prevent a turnup portion of the carcass from being pulled downwards, the first reinforcing rubber layer being located around a portion of the bead core that is oriented toward a rim flange. The bead portion is improved in durability under a high-pneumatic-pressure condition by reducing the stress applied to interfaces of the edge of the carcass, the steel chafer and the nylon chafer.

Disclosed herein is a bead reinforcing device for pneumatic tires, which includes a bead forming a circumference of a tire as a portion where the tire is in contact with a wheel, a carcass formed to cover the bead from its inside to its outside and forming an entire frame of the tire, and a bead stiffener formed to cover an entire outer surface of the bead.

Provided is a pneumatic tire for two-wheeled motor vehicles in which the durability of bead portions is improved than in conventional tires. This pneumatic tire includes: a tread portion formed in an annular shape; side wall portions and bead portions, which continuously extend on the respective ends of the tread portion; a carcass 1 composed of at least three layers of carcass plies 1a, 1b and 1c which toroidally extend on the tire radial-direction inner side of the tread portion; a belt 2 composed of at least two belt layers 2a and 2b which are arranged on the tire radial-direction outer side of the carcass 1; and bead cores 3 embedded in the bead portions. In this pneumatic tire, the carcass plies 1a, 1b and 1c; have a bias structure and include at least two layers of turn-up carcass plies 1a and 1b which are folded back around the bead cores 3, and at least one layer of down carcass ply 1c which is arranged on the tire radial-direction outer side of the turn-up carcass plies and terminated on the tire width-direction outer side of the bead portions without being folded back around the bead cores 3.

The invention relates to a rubberized reinforcing ply for articles made of elastomeric material, preferably for vehicle tires, where the reinforcing ply has a multiplicity of parallel strengthening elements spaced apart from one another, with each strengthening element consisting of polyamide 6.6 and having an x1 construction, hence being a twisted multifilament yarn of polyamide 6.6. The crude yarn of polyamide 6.6 has a tenacity which, at an elongation of 4%, is within a range from 1.35 cN/dtex to 1.60 cN/dtex; the multifilament yarn has a tenacity which, at an elongation of 4%, is within a range from 2.0 cN/dtex to 2.8 cN/dtex, and the cord has a thermal shrinkage at 177 within a range of 4.0%-7.0%, wherein the tenacity in accordance with ASTM D885-16 and the thermal shrinkage at 77 C. are determined under a pre-tension of 0.045 g/dtex with an exposure time of two minutes.

The invention relates to a rubberized reinforcing ply for articles composed of elastomeric material, preferably for vehicle tires, wherein the reinforcing ply has a multiplicity of strengthening elements which are in parallel and spaced apart, wherein each strengthening element is a cord which is end-twisted from at least two twisted multifilament yarns composed of polyamide 6.6. The raw yarn composed of polyamide 6.6 has a tenacity which, at an elongation of 4%, is within a range from 1.35 cN/dtex to 1.60 cN/dtex, the cord has a tenacity which, at an elongation of 4%, is within a range from 1.2 cN/dtex to 2 cN/dtex and the cord has a thermal shrinkage at 177 within a range of 4.0%-7.0%, wherein the tenacity in accordance with ASTM D885-16 and the thermal shrinkage at 177 C. are determined under a pre-tension of 0.045 g/dtex with an exposure time of two minutes.

A tire (1) has two annular beads, a toroidal body ply (2) which is wound about the two beads (3) to form two turn-ups, and two bead fillers (8). Each bead filler (8) contacts a bead (3) and is at least partly enclosed in a turn-up (4) of the body ply (2), and comprises an elastomer filler strip (9) which is wound about the bead (3) and is interposed between the bead (3) and the body ply (2) and has two opposite ends (10, 11) located on opposite sides of the bead (3) and contacting each other. An outer end (11) of the filler strip (9) of each bead filler (8) is folded into a U about the corresponding end of the body ply (2) so as to enclose the end of the body ply (2).

A pneumatic tire for heavy loads comprising a bead core, a bead filler arranged on the outside in a tire radial direction of the lead core, a steel cord-containing carcass ply wound up on the outside from the inside in a fire axis direction around the bead core, a steel cord-containing chafer provided so as to cover the carcass ply from the inside in the tire radial direction, and a reinforcing sheet comprising a rubber and a cotton kneaded therein and interposed between the bead core and the carcass ply. The tire can improve durability of a bead part.

Provided are: a rubber-reinforcing fiber, in which adhesion between a rubber and a fiber is enhanced and which is thereby capable of further improving the durability than before when used as a reinforcing material; a rubber-fiber composite; and a pneumatic tire using the same. The rubber-reinforcing fiber includes a core-sheath type composite fiber whose core portion is composed of a high-melting-point resin (A) having a melting point of 150 C. or higher and sheath portion is composed of a resin material (B) having a melting point lower than that of the high-melting point resin (A). The resin material (B) includes: an olefin-based random copolymer (C) and/or an olefin-based homopolymer or olefin-based copolymer (D) (excluding (C)); and a styrene-based elastomer (E) containing a monomolecular chain in which mainly styrene monomers are arranged in series.