A manufacturing device for a pneumatic tire in which a carcass ply includes a pair of ply pieces includes a molding drum, a drum drive device, a first supply device for supplying one of the ply pieces to the molding drum, a second supply device for supplying the other one of the ply pieces to the molding drum, and a control device that controls operation of the drum drive device and the first and second supply devices so that the one and the other one of the ply pieces are simultaneously supplied to the molding drum while the molding drum is rotationally driven, and two joint portions of the one and the other ply pieces are provided at different positions in the tire circumferential direction.

A manufacturing device for a pneumatic tire in which a carcass ply includes a pair of ply pieces includes a molding drum, a drum drive device, a first supply device for supplying one of the ply pieces to the molding drum, a second supply device for supplying the other one of the ply pieces to the molding drum, and a control device that controls operation of the drum drive device and the first and second supply devices so that the one and the other one of the ply pieces are simultaneously supplied to the molding drum while the molding drum is rotationally driven, and two joint portions of the one and the other ply pieces are provided at different positions in the tire circumferential direction.

A pneumatic tire includes a carcass ply stretching between a pair of bead cores disposed on both sides in the tire width direction, and the carcass ply includes a pair of ply pieces disposed separately on both sides in the tire width direction. Each of a pair of the ply pieces has a joint portion in which both end portions in the tire circumferential direction are joined in a manner overlapping each other, and the respective joint portions of a pair of the ply pieces are provided at different positions in the tire circumferential direction.

A tire with improved handling having a stiffening structure with a stiffening element extending continuously in the toroidal interior cavity from a crown interface connected to a radially inner face of the crown to a bead interface connected to an axially inner face of the bead. The stiffening structure is distributed circumferentially over the circumference of the tire, the axially outermost stiffening element interface is positioned, with respect to the equatorial plane (XZ), at an axial distance A at most equal to 0.45 times the axial width S, and the radially outermost stiffening element bead interface is positioned, with respect to a radially innermost point (I) of the axially inner face of the bead at a radial distance B at most equal to 0.5 times the radial height H.

Provided is a pneumatic tire. One terminal of a carcass layer extends to a ground contact edge of a tread portion positioned on an opposite side with respect to a tire center line as a reference. The carcass layer has a double layer structure including an inner layer positioned inward in a tire radial direction in a tread region and an outer layer positioned outward in the tire radial direction of the inner layer in the tread region. A cord angle in the carcass layer in a tread central region with respect to a tire circumferential direction is different from a cord angle in at least one of the inner layer and the outer layer of the carcass layer in a side region with respect to the tire circumferential direction.

Provided is a pneumatic tire. One terminal of a carcass layer extends to a ground contact edge of a tread portion positioned on an opposite side with respect to a tire center line as a reference. The carcass layer has a double layer structure including an inner layer positioned inward in a tire radial direction in a tread region and an outer layer positioned outward in the tire radial direction of the inner layer in the tread region. A cord angle in the carcass layer in a tread central region with respect to a tire circumferential direction is different from a cord angle in at least one of the inner layer and the outer layer of the carcass layer in a side region with respect to the tire circumferential direction.

A pneumatic tire 1 comprises a carcass 6 comprising at least one carcass ply 6A extending between bead portions 4 via sidewall portions 3 and a tread portion 2. The carcass ply 6A comprises strip-shaped ply pieces 11 longer in a tire radial direction than in a tire circumferential direction arranged circumferentially. Each of the ply pieces 11 comprises a plurality of carcass cords 12 arranged in parallel in the tire radial direction and at least partly overlapping each other with the ply pieces 11 circumferentially adjacent. At least one of the carcass cords 12 arranged in at least one of side edge portions 11e in the tire circumferential direction of each of the ply pieces 11 having a diameter (Ce) smaller than a diameter (Cc) of at least one of the carcass cords 12 arranged in a center portion 11c of each of the ply pieces 11.

A pneumatic tire 1 comprises a carcass 6 comprising at least one carcass ply 6A extending between bead portions 4 via sidewall portions 3 and a tread portion 2. The carcass ply 6A comprises strip-shaped ply pieces 11 longer in a tire radial direction than in a tire circumferential direction arranged circumferentially. Each of the ply pieces 11 comprises a plurality of carcass cords 12 arranged in parallel in the tire radial direction and at least partly overlapping each other with the ply pieces 11 circumferentially adjacent. At least one of the carcass cords 12 arranged in at least one of side edge portions 11e in the tire circumferential direction of each of the ply pieces 11 having a diameter (Ce) smaller than a diameter (Cc) of at least one of the carcass cords 12 arranged in a center portion 11c of each of the ply pieces 11.

The present invention relates to a tire cord and a radial pneumatic tire, and is characterized in that when one raw nylon 6,6 or nylon 6 yarn and one aramid yarn are pre-twisted respectively and are then cabled to generate a raw cord, and when the raw cord is untwisted, the aramid yarn is input 5 to 100 mm/m longer than the nylon 6,6 or nylon 6 yarn. The hybrid dip cord according to the present invention has an excellent fatigue resistance of 80% or more, the initial deformation in the tensile test causes low modulus to be generated by nylon and causes high modulus to be expressed from the section where aramid begins to receive the force. As such, deformation is easy during the work of inflating the green tire inside the mold with the bladder, which makes the manufacturing of tires easy.

Another object of the present invention relates to a method for producing a hybrid dip cord using nylon 6,6 yarn and aramid yarn, in which nylon 6,6 yarn and aramid yarn are pre-twisted by using one selected from the group consisting of a method of controlling the tension applied to the live cord, a method of adjusting the heat treatment temperature, and a method of controlling the heat treatment time, and they are cabled to make a raw cord, then the raw cord is dipped in an adhesive and is then heat-treated to thereby produce a dip cord in which nylon 6,6 has been further shrunk.

Another object of the present invention is to provide a hybrid dip cord for a carcass ply or cap ply layer of a pneumatic radial tire having a certain degree of fatigue resistance, which is produced by dipping the raw cord using the nylon 6,6 and the aramid yarn in a dipping solution and then heat-treating the raw cord so that the nylon 6,6 may further shrink.

In the present invention, twist numbers of aramid yarn and nylon yarn are kept the same during twisting, to thereby allowing a heat treatment process after producing a raw cord, by which the nylon yarn shrinks, and the aramid yarn is set to be longer than the nylon yarn per unit length when the dip cord is untwisted, thereby increasing the fatigue resistance. According to the present invention, it is possible to overcome the disadvantage that it is difficult to deform in a mold with a high modulus when using the aramid alone, and it is possible to improve low fatigue resistance and adhesion which are problematic when using aramid alone, and it is possible to produce high performance tires by improving low modulus and heat resistance that are problematic when using nylon 6,6 alone.

Further, a method of manufacturing a hybrid dip cord according to the present invention includes: a step of preparing one nylon 6,6 yarn or ny

A pneumatic tire includes a carcass whose cords are coated with coating rubber, at least one of a bead core and a bead filler whose outer surface which faces the carcass is formed from a resin that is harder than the coating rubber, and a buffer layer that is disposed between the coating rubber and the resin, and that reduces shear stress generated in the coating rubber.