The Yokohama Rubber Co., Ltd.

Zenichiro Shida

Yoshiaki Hashimura

Tomohiko Kogure

Yusaku Miyazaki

Masakazu Okihara

Naoyuki Katsura

Masataka Koishi

Riichiro Mama

Daisuke Kanenari

Kazuto Yamakawa

Jiro Watanabe

Hiroyuki Kaido

Takashi Shibai

Tadashi Higuchi

A pneumatic tire includes a carcass layer and belt layers including belt cords inclined with respect to a circumferential direction, the belt cords of different layers being arranged in a criss-cross manner. In at least one belt layer, an inclination angle &#x3b1; of the belt cords with respect to the circumferential direction at a center position and an inclination angle &#x3b2; of the belt cords with respect to the circumferential direction at a belt end position satisfy 15&#xb0;&#x2264;&#x3b2;&#x3c;&#x3b1;&#x2264;35&#xb0;. A maximum ground contact length Land a ground contact length Lsatisfy 0.8&#x2264;L/L, where Lis the maximum ground contact length in the circumferential direction, Wis a maximum ground contact width in a radial direction, and Lis the ground contact length in the circumferential direction at a position 40% of Wfrom the center position outward in a lateral direction.

Pneumatic tire

A pneumatic radial tire wherein both end portions of at least one layer of a carcass layer are turned up around right and left bead cores from the inside to the outside of the tire, and at least two layers of belt layers formed by arranging reinforcing cords in such a fashion that their inclining directions with respect to a tire circumferential direction cross one another in mutually opposite directions between the layers are disposed on the outer circumferential side of the carcass layer of a tread portion. A carcass strength coefficient K defined by the formula (1) in the specification is 0.15 to 0.35 N/mm&middot;kPa at portions on the tread portion center side of positions P which are away by 10% of a belt width of a belt layer having the second greatest width from both edges thereof towards its inside, and is 0.5 N/mm&middot;kPa at portions from the positions P to the bead portions.

Pneumatic radial tire with specified carcass strength coefficient

A pneumatic tire comprises a carcass layer provided between a pair of left and right bead sections, each of both end parts of the carcass layer in a tire width direction being turned up around a bead core from the inside of the tire to its outside, and a bead apex arranged in an outer peripheral side of the bead core, wherein at least a 30% area of a cross-sectional area of the bead apex positioned in a range of 20 to 35% of a tire section height SH is made of low tan &dgr; rubber which is set in a range of 25 to 75% of tan &dgr; of base bead apex rubber for a bead apex main body.

Pneumatic tire with specified rubber properties

A pneumatic tire constituting part or all of the part members constituting the pneumatic tire by a rubber composition containing, based on a total 100 parts by weight of a rubber containing at least 70 parts by weight of an ethylenic unsaturated nitrile-conjugated diene-based highly saturated rubber having a content of conjugated diene units of not more than 30 percent by weight, 0 to 120 parts by weight of zinc methacrylate and 0 to 60 parts by weight of carbon black and having a total of formulations of zinc methacrylate and carbon black of 10 to 120 parts by weight, and providing, between the above part members and the adjoining diene-based rubber layer, a bonding rubber layer comprising of a rubber composition containing, based on a total 100 parts by weight of a predetermined diene-based rubber and acrylonitrile butadiene copolymer rubber, 5 to 80 parts by weight of a predetermined aromatic petroleum resin.

Pneumatic tire having crescent sectional shape reinforcing liner layer

Disclosed is a pneumatic tire which comprises a carcass layer provided between a pair of left and right bead sections, left and right side wall sections interpolated for connecting the pair of left and right bead sections with a tread section to be continuous, and at least two belt layers provided in an outer peripheral side of the carcass layer in the tread section, each of the belt layers being composed of a plurality of reinforcing cords coated with coating rubber. Storage elastic modulus E&prime; of the coating rubber is set in a range of 15.0 to 40.0 MPa, and its loss tangent tan &dgr; is set in a range of 0.1 to 0.25. Interlayer rubber is provided between end parts of the belt layers, the interlayer rubber being specifically set in each of both end parts thereof in a tire width direction, and elongation to break Eb of the interlayer rubber is set in a range of 400 to 700%. In another embodiment, at least a 30% area of a cross-sectional area of the bead apex positioned in the range of 20 to 35% of a tire section height SH is made of low tan &dgr; rubber which is set in a range of 25 to 75% of tan &dgr; of base bead apex rubber for a bead apex main body.

A pneumatic tire for passenger cars, having a carcass layer laid between left and right beads, and two belt layers provided in an outer peripheral side of the carcass layer in a tread, wherein a width of a second belt layer counted from the side of the carcass layer is set to 95-110% of a ground contacting width of the tread, a recess being provided in each shoulder so that the center of the recess is positioned in a region separate from a position of the shoulder which corresponds to an edge of the second belt layer toward a relative bead by a distance in the range of 8-14% of a width of the same belt.

Pneumatic tire for passenger cars having shoulder recess

Pneumatic tire with air permeation preventive layer

A pneumatic tire to be fitted on a wheel wherein a position, in which a disc is connected to a rim, is offset from the cneter of width of the rim toward the outer surface of the wheel, characterized in that a ratio (Ho/Hi) of an attenuation coefficient Ho (=Go.times.tan.delta.o) determined on the basis of an average thickness Go of an outer side wall of the tire on the outer side of the wheel and a loss factor tan.delta.o of the rubber of this side wall to that Hi (=Gi.times.tan.delta.i) determined on the basis of an average thickness Gi of an inner side wall of the tire on the inner side of the wheel and a loss factor tan.delta.i of the rubber of this side wall is set in the range of 1.2-6.5.

Pneumatic tire and wheel with asymmetric structure

A pneumatic tire characterized in that an average thickness G.sub.U of the region of each of side walls which extends from a position corresponding to a widest portion of the tire toward a tread and that G.sub.L of the region of the side wall which extends from the same position toward a bead are set different from each other, the average thickness G.sub.U of the tread-side region being set to not less than 2.5 mm with the average thickness G.sub.L of the bead-side region set to less than 2.5 mm and not less than 1.0 mm.

Pneumatic tire with different side wall thickness in tread-side and

In a pneumatic tire which is to be fitted to a wheel of the type in which connecting position of a disc to a rim is offsetted to a wheel outer side from a center of a rim width, and which has a plurality of blocks on a tread thereof, a pneumatic tire wherein a total contact area C.sub.2 of shoulder blocks on the tire outer side disposed on the offset side of the disc and a total contact area C.sub.1 of shoulder blocks on the tire inner side disposed on the opposite side to the offset side of the disc satisfy the relation, C.sub.1 /C.sub.2 =1.2 to 2.0.

Pneumatic tire with asymmetrical tread shoulders

A pneumatic radial tire to be fitted on a wheel in which a position wherein a disc is joined to a rim is offset from the center of the width of the rim toward the outer surface of said wheel, characterized in that the tire comprises an asymmetric structure in which a belt layer is provided between a tread and a carcass layer, an outer circumferential portion of the belt layer being covered with at least one belt covering layer, the at least one belt covering layer being disposed so that an average position of the center(s) of the width(s) thereof from the equator of the tire is deviated toward the opposite side of the offset side of the disc, a ratio e/w of the deviating distance e to the width w of a ground contacting portion of the tread being set to 0.05-0.13.

Pneumatic radial tire having asymmetric belt covering layers

A pneumatic radial tire characterized in that at least two belt layers reinforced with cords of a high elastic modulus extending at an angle of 14.degree.-33.degree. with respect to the circumferential direction of the tire are arranged between a tread and a carcass, at least one of these belt layers being folded back at both end portions thereof toward the equator of the tire so as to wrap both end portions of any remaining belt layers, at least one reinforcing layer which is reinforced with thermally contractible organic fiber cords which extend at substantially 0.degree. with respect to the circumferential direction of the tire being inserted inside of each of the folded portions of the at least one folded belt layer, the width of the reinforcing layers being set to 10-70% of that of each of the folded portions.

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Hiratsuka, Japan

Zenichiro Shida