Sumitomo Rubber Industries Limited

The Goodyear & Tire Rubber Company

Minoru Nishi

Kiyoto Maruoka

Satoshi Tsuda

Atsushi Yamahira

Kiyoshi Ueyoko

Takahiro Kimishima

Kazumi Yamazaki

Tsuneyuki Nakagawa

Kiyohito Maruoka

Tomoyasu Shibata

Yoshiyuki Takada

Tomoyuki Kujime

Kazuki Numata

Naoki Sugiyama

Mitsuharu Koya

Taro Okabe

Hiroshi Okagawa

Makoto Igarashi

Masakazu Washizuka

Takeshi Kuroki

Naoki Asakawa

Joachim Riegel

Hirotoshi Ohtsuki

Jyunji Ohira

Anton Haring

Anton Häring

A vehicle tire includes a tread portion provided in the tread surface with a circumferentially continuously extending groove having a bottom and a pair of opposite side walls, wherein at least one of the side walls is provided with protrusions protruding into the groove and arranged in the tire circumferential direction. The protrusion has a gradually increasing part in which the area of the cross section of the protrusion being parallel with the tread surface is gradually increased toward the radially outer side of the tire.

Tire

A heavy duty pneumatic tire includes a tread portion provided with circumferentially extending zigzag shaped main grooves, a plurality of land portions separated by the main grooves, and a plurality of lateral grooves to form a plurality of block elements on each land portion. Each land portion comprises a number of pitches in a range of from 40 to 50, wherein each pitch consists of one block element and one lateral groove adjacent to the concerned block element. Each block element has a length in a range of from 85% to 95% of a length of the pitch. The main grooves include a crown main groove, a shoulder main groove, and a middle main groove. The middle main groove has a zigzag amplitude larger than those of the crown main groove and the shoulder main groove.

Heavy duty pneumatic tire

Pneumatic vehicle tire, in particular a run-flat tire, having a carcass, a tread, and two tire beads, having a respective bead core, which are provided for fixing the tire in an associated wheel rim by the fact that the beads overlap with the associated wheel rim. According to the invention, to avoid relative motion between the tire bead and the wheel rim when the tire is subjected to impact load, the bead is designed in such a way in the nonloaded state mounted on the wheel rim the bead does not overlap with the wheel rim in the contact region of the wheel rim flange above the bead core.

Run-flat tire

A heavy duty tire has a tread portionwhich is divided into five inner, intermediate and outer rib-like land portions R, R, R, Rand R. The inner rib-like land portion Ris virtudally divided into half regions Rand Ron each side of a tire equator. The intermediate rib-like land portions Rand Rare virtually divided into tire equator-side half regions Rand R, and into ground-contact edge-side half regions Rand R. In a regular ground-contact state in which a normal load is applied, when total sums of ground-contact load applied to the half regions R, R, R, Rand Rare defined as P, P, P, Pand P

Heavy duty tire with tread portion having three longitudinal main grooves

In a ground-contact surface shape of a tire, when a tangent angle formed between an axial direction of the tire and a tangent X at each point P on a profile line of the tire is defined as &#x3b8;, a tangent angle &#x3b8;in a ground-contact end point Pd is 25&#xb0; or smaller. When a minimum value of the tangent angle &#x3b8; in a region Y which is separated away from a tire equator C by a distance in a range of not less than 0.4 times but not more than 0.7 times a half of the ground-contact width of the tread is defined as &#x3b8;, and a tangent angle at a 0.9 times point Pq which is separated away from the tire equator C by a distance of 0.9 times the half of the ground-contact width of the tread is defined as &#x3b8;, a difference (&#x3b8;) is set in a range of not less than &#x2212;10&#xb0; but not more than +10&#xb0;.

Heavy-duty tire having ground-contact surface shape

A heavy duty tire including bead portions each with a bead core, and a carcass ply containing a main portion extending between bead portions and a pair of edge portions wound around the bead cores, the wound edge portion including a turnback part extending axially inwardly from a position on the axially outside of the bead core and an auxiliary cord layer disposed on the radially outside of the turnback part, whereby the end of the turnback part is positioned at a distance of from 2.0 to 8.0 mm from the radially outer surface of the bead core. In a normally inflated unloaded state of the tire, the turnback part is curved such that the diameter of the turnback part decreases continuously from the end to the position in the axial outside of the bead core.

Heavy duty tire

A pneumatic tire comprises a tread portion, a pair of sidewall portions, a pair of bead portions, a bead core disposed in each bead portion, a carcass comprising a ply of carcass cords extending between the bead portions through the tread portion and sidewall portions and turned up around the bead core in each bead portion, and an inner liner made of air-impermeable rubber extending on the tire cavity side of the carcass from one of the bead portions to the other. The radially inner end of the inner liner is located radially inside the radially innermost end of the carcass. In a radial region between the radially innermost end of the carcass and the radially outermost end of the bead core, the thickness of the inner liner is not less than 0.15 time but not more than 4.0 times the cross section diameter of the carcass cord.

Pneumatic tire with specified inner liner

A heavy duty pneumatic radial tire includes a carcass ply, in which a ply folding portion folding a bead core is successively disposed in a ply body. The ply folding portion includes a main portion folded along the bead core, and a winding-up portion extending continuously to the main portion and apart from the bead core. The winding-up portion extends with an inclination of an angle &#x3b8; in a direction in which a diameter is increased inward in the tire axial direction, the angle &#x3b8; being set to 20 to 65 degrees with respect to an upper surface in the radial direction of the bead core, a distance La from the upper surface in the radial direction of the bead core at the inner end point of the winding-up portion being set to 5 mm to 15 mm, and a distance Lb between the inner end point of the winding-up portion and the ply body being set to 1 mm to 5 mm.

Heavy duty pneumatic radial tire with carcass ply winding-up portion

The present invention relates to a heavy duty tire comprising a carcass comprising a carcass ply of cords extending between bead portions and turned up around a bead core in each bead portion from the inside to outside of the tire so as to form a pair of turnup portions and a main portion therebetween, and a bead reinforcing layer comprising at least one reinforcing ply of cords disposed of each said bead portion, wherein

A pneumatic tire comprises a tread portion with tread edges, a pair of sidewall portions, a pair of bead portions each with a bead core therein, and a carcass ply of cords comprising a main portion extending between the bead cores through the tread portion and sidewall portions and a wound portion wound around the bead core in each said bead portion from the inside to the outside of the tire, and an edge of the wound portion is disposed between the bead core and a bead apex rubber disposed radially outside the bead core to be secured therebetween.

Pneumatic tire

A heavy duty radial tire which is provided with traverse grooves extending between the tread edges and longitudinal grooves extending between the traverse grooves so as to form shoulder blocks arranged along each of the tread edges and inner blocks each disposed on the axially inside of one of the shoulder blocks. The longitudinal grooves between the shoulder blocks and the inner blocks have a depth Dga of 0.7 to 1.0 times the depth Dy of the traverse grooves, and the longitudinal grooves are each inclined at an acute angle with respect to the circumferential direction to have an axial extent range Y whose axial width W1 is in a range of from 1.0 to 10.0 times the width Wga. In a cross section of the tire under a normally inflated unloaded condition, the tread profile is made up of a center profile Si and a shoulder profile So. The shoulder profile So extends continuously from each of the axial ends of the center profile Si through an inflection point P to one of the tread edges. The center profile Si is a circular arc of a radius Rc having the center on the tire equatorial plane, and the shoulder profile So is a substantially straight line or alternatively an arc having less curvature than the center profile Si. The inflection point P is located within the axial extent range Y of the longitudinal grooves.

Heavy duty radial tire

A standard grounding surface shape Fbecomes a maximum grounding length Lc at a tire equator C and becomes a shortest grounding length Lm between the tire equator C and a grounding edge TE. The shortest grounding length Lm is located in a region away from the tire equator C by a distance of 0.5 to 0.9 times of a tread half width TW. A rubber thickness tbetween the carcass cord and the belt cord is gradually increased outward in the axial direction of the tire from the tire equator, and the rubber thickness tin a half width position Q which is away from the tire equator by a distance of 0.55 times of the tread half width TW is set to 0.5 to 3.0 mm. A ratio t/tbetween a tread entire thickness tin the half width position Q and a tread entire thickness tin the tire equator is set to 1.01&#xb1;0.05.

In a pneumatic tire, a cord spacing between an axially outer cord layer and an axially inner cord layer such as: a turnup portion and a main portion of a carcass ply; or a bead reinforcing cord layer and a carcass ply turnup portion, is increased from the radially inside to the outside of the tire to improve the durability of the bead portion.

When a tread thickness from a second belt plyB is defined as T, Tmin is provided in a region Y which is away from a tire equator C by a distance of 0.5 to 0.7 times of a tread grounding half width WT/2. A ratio Tmin/Tc between said minimum value Tmin and the tread thickness Tc at the position of the tire equator C is 0.92 to 0.97, and a ratio Tb/Tc between a tread thickness Tb at a position of an outer end of the second belt ply and Tc is 0.95 to 1.10. When a tread thickness from a carcassis defined as K, Kmin is provided in region Y. A ratio Kmin/Kc is 0.97 to 0.998, and a ratio Kb/Kc is 1.2 to 1.5.

Growing community of inventors

Kobe, Japan

Minoru Nishi