The Yokohama Rubber Co., Ltd.

Tetsuya Kuze

Toshihiko Suzuki

Izumi Kuramochi

Hiroshi Tokizaki

Masahiro Ishida

Yoshimasa Hashimoto

Tuneo Morikawa

Hisaya Morishita

Kenichi Shirai

Takashi Yamashita

Sadakazu Takei

Kohtaroh Iwabuchi

Hiroshi Hata

Masakazu Niwa

Kenichiro Sugitani

Junichi Ohtani

Disclosed is a pneumatic tire provided with multiple blockson a tread. A sipeprovided on the blockis formed by shifting pitches of a zigzag shapeon a tread faceside of the sipe and a zigzag shapeon a bottom side thereof in the width direction of the tire, and by connecting concave and convex flexion points a, a', b and b&#x2032; on the both of the zigzag shapes with edge lines xxand xThe blockis sectioned by the sipeinto a concavo-convex face A in which convex triangular pyramids Aa and convex reverse triangular pyramids Ab are alternately arranged, and a concavo-convex face B in which concave triangular pyramids Ba and concave reverse triangular pyramids Bb are alternately arranged. The concavo-convex faces A sectioned by the sipes are at least disposed in both outermost positions in the circumferential direction of the block in a manner that the concavo-convex faces A are oriented outward from the block.

Pneumatic tire having sipes formed by shifting pitches of zigzag shape

In a pneumatic tire including sipes extending in zigzag provided on tread surfaces, both wall surfaces of each sipe, which face to each other, are inclined with respect to a diameter direction of the tire, constituted of triangular wall surfaces, each having two sides expanding toward a sipe bottom with a bending point of a zigzag of the sipe as an apex and of inverse triangular wall surfaces, each having two sides narrowed toward the sipe bottom with one side of the zigzag of the sipe as a base, and a pair of the triangular wall surfaces adjacent to each other and a pair of the inverse triangular wall surfaces adjacent to each other are alternately arranged. Thus, provided is a pneumatic tire capable of improving ice performance without lowering driving stability on a dry road surface, and of suppressing occurrence of uneven wear.

Pneumatic tire having sipes

Automobile tire

A pneumatic radial tire has a tread pattern having a pair of straight main grooves each having a width equal to 8-13 percent of a ground contact width W of the tire and extending in parallel on opposite sides of an equator of the tire, a plurality of lug grooves extending across shoulder regions formed on the outersides of the pair of main grooves from the pair of main grooves outwardly toward the ends of the ground contact surface of the tire to form in cooperation with the main grooves successive rows of blocks, and a plurality of V-shaped sub-grooves in the shoulder regions spaced at a predetermined pitch apart in the circumferential direction of the tire and extending divergently with respect to the direction of reverse rotation of the tire, wherein the ratio of a distance W1 between respective centers of the main grooves to the ground contact width W is in the range of 0.2.ltoreq.W1/W.ltoreq.0.4; an angle .alpha. of inclination of the lug grooves with respect to the circumferential direction of the tire as viewed from the reverse tire rotating direction is in the range of 90.degree.-130.degree.; and an angle .beta. defined by the V-shaped sub-grooves is in the range of 15.degree.-35.degree..

Pneumatic radial tire

A pneumatic tire having a tread pattern comprising a rib and a block, wherein a rib having the highest rigidity in the circumferential direction of the tire of said at least one rib is offset from the equatorial line of the tire to the shoulder side which is located on the outer side of a vehicle when the tire is mounted on the vehicle and the position of mounting of this rib and the width of the main groove on the shoulder side adjacent to this rib are specified respectively by formulae (I) and (II) described in the specification.

Pneumatic tire having the highest rigidity tread rib offset from the

A pneumatic radial tire characterized in that:

Pneumatic radial tire with improved bead structure

A pneumatic radial tire having a block pattern asymmetric about the right and left portions on the ground-contacting portion of the tire which has a specific area ratio of grooves and a specific angle of subgrooves on the ground-contacting portion of the tire.

Asymetric pneumatic radial tire tread for passenger car

A radial tire for a passenger car characterized in that an upper filler is disposed on a bead filler positioned on a bead wire buried in each bead portion of the tire, and a single steel reinforcing layer is interposed between the upper filler and the bead filler so that it extends from outside the upper filler to the inside of the bead filler and its height H from a bead heel does not exceed 50% of a sectional height T of the tire.

Growing community of inventors

Hiratsuka, Japan

Tetsuya Kuze