Bridgestone Corporation

Yoshihide Kohno

Hiroyuki Koseki

Yoichi Okamoto

Takayuki Sato

Eiji Yamanaka

Toshiya Miyazono

Toshinobu Kobayashi

Kuninobu Kadota

Kiyoshi Sato

Makoto Tsuruta

Yasuhiko Kobayashi

Yasuo Ohsawa

Takahiro Kimura

Norinaga Matsushita

A pneumatic radial tire includes a belt comprised of at least two rubberized steel wire element layers, in which the belt comprises an outermost slant element layer containing the steel wire elements obliquely arranged with respect to an equatorial plane of the tire and at least one circumferential element layer located inward from the outermost slant element layer in a radial direction of the tire and containing the steel wire elements arranged substantially in parallel to the equatorial plane, and a coating rubber for the steel wire element in the outermost slant element layer has a given modulus of elasticity at compression, and a sum of sectional area of the steel wire elements in the circumferential element layer per unit length is larger than a sum of sectional area of the steel wire elements in the outermost slant element layer per the same unit length.

Pneumatic radial tires with specified steel belts

A pneumatic radial tire for passenger car comprises a circumferential belt layer in addition to a slant belt layer, in which specified PET, nylon, PEN or vinylon fiber cords or steel cords are used in the circumferential belt layer.

Pneumatic radial tires with circumferential cord belt layer having specified cord twisting structure

A pneumatic radial tire for passenger cars comprises a circumferential belt layer in addition to a slant belt layer, in which specified PET, nylon, PEN or vinylon fiber cords or steel cords are used in the circumferential belt layer.

A heavy duty pneumatic radial tire comprises a radial carcass extending between a pair of bead cores, and a belt comprised of three rubberized cord layers, among which cord layers an innermost cord layer and a middle cord layer being laminated to form a cross belt layer by crossing cords of these cord layers with each other with respect to a plane including a circumference of the tire, in which an inclination cord angle with respect to the plane in the innermost cord layer and the middle cord layer is within a given range, and cords in an outermost cord layer have a given inclination cord angle as measured from the plane toward a direction of measuring the inclination cord angle of the middle cord layer, and a coating rubber for the outermost cord layer has a given modulus of elasticity.

Heavy duty pneumatic radial tires with specified coating rubber of

Pneumatic radial tires with circumferential cord belt layer having

A tire component used in a pneumatic radial tire is a rubber-coated layer comprised of a given number of reinforcing elements separately arranged in parallel with each other, in which the reinforcing elements corresponding to at least 30% of all reinforcing elements included in the rubber-coated layer are divided into plural groups, and a distance between mutually adjoining and opposite reinforcing elements not grouped with each other is wider than a distance between mutually adjoining reinforcing elements separately arranged at equal spaces in the group. Thus, the occurrence of cracking at cut ends of the reinforcing elements is prevented to improve the tire durability.

Pneumatic radial tires including a tire component containing groups of

A tire component used in a pneumatic radial tire is a rubber-coated layer comprised of a given number of reinforcing elements separately arranged in parallel with each other, in which the reinforcing elements corresponding to at least 30% of all reinforcing elements included in the rubber-coated layer are divided into plural groups, and a distance between mutually adjoining and opposite reinforcing elements not grouped with each other is wider than a distance between mutually adjoining reinforcing elements separately arranged at equal spaces. Thus, the occurrence of cracking at cut ends of the reinforcing elements is prevented to improve the tire durability.

A pneumatic radial tire comprising a toroidal carcass layer having a number of radially extending cords buried therein, a belt layer arranged on a radially outer side of the carcass layer and containing a number of nonstretchable cords inclined to an equatorial plane of the tire, and a reinforcing layer arranged between the carcass layer and the belt layer and containing a number of reinforcing elements. The reinforcing elements extend in parallel to the tire equatorial plane as a whole, and are waved at a substantially equal wavelength. The phase of a plurality of the reinforcing elements among all the reinforcing elements buried in the reinforcing layer is different from that of the remaining reinforcing element or elements.

Pneumatic radial tires including waved reinforcing elements between belt

A pneumatic tire includes a toroidal carcass anchored by at least a pair of bead cores and a belt having strips. The strip has as reinforcing elements a plurality of zigzag or wave-shaped cords or filaments arranged side by side around a crown of the toroidal carcass. The strip is coated with a high molecular weight material less in modulus of elasticity than the reinforcing elements. Waves of the reinforcing elements of the strips are arranged in width directions of the belt so that ratios of amplitudes to wave lengths of the waves are maximum at side edges of the belt. The ratios are preferably progressively increased toward the side edges of the belt. Ratios of amplitudes to pitches of the waves are 0.005-0.175 and ratios of pitches of the waves to maximum circumferential lengths when filled with a normal inner pressure is less than 0.025.

Pneumatic tire including wave-shaped cords or filaments

A pneumatic radial tire including a carcass layer having cords embedded therein and arranged perpendicular to an equatorial plane of the tire, and a belt layer including at least one belt ply having a large number of cords embedded therein, the cords including one or more filaments. The cords are disposed radially outside of said carcass layer, arranged substantially in parallel to the equatorial plane of the tire and bent in a wavy or zigzag form. At least those of the cords or filaments located at widthwise outermost locations in the parallel belt ply satisfy the following expression:

Pneumatic radial tire including wavy or zigzag belt cords

A pneumatic tire for a passenger car includes a toroidal carcass anchored by a pair of beads and a belt made of laminated strips. The strips have a number of reinforcing elements of cords or filaments surrounding a crown of the toroidal carcass and are coated with a high molecular weight material having a modulus of elasticity less than that of the reinforcing elements. The belt is of a laminated construction of a first layer and a second layer of a single strip. The first layer has wave-shaped reinforcing elements arranged side by side and directing in parallel with an equatorial plane of the tire, while the second layer has reinforcing elements arranged in parallel with each other at angles of 15.degree.-75.degree., preferably 35.degree.-60.degree. with respect to the equatorial plane.

Pneumatic tire for passenger car including wave-shaped belt reinforcing

A crown portion of a pneumatic tire comprising at least one radial carcass ply and a belt of at least two cross belt layers is reinforced by arranging a strip containing wavy or zigzag-like cords or filaments between the carcass ply and the belt as a crown reinforcing layer.

Growing community of inventors

Kodaira, Japan

Yoshihide Kohno