Abstract:
Disclosed is a run-flat tire having greatly increased run-flat endurance. The disclosed run-flat tire is provided with: a carcass (6) extending from a tread section (2) through a sidewall portion (3) to a bead core (5) of a bead portion (4); and a side-reinforcement rubber layer (9) that has a crescent-shaped cross-section and is disposed inside the carcass (6) in the sidewall portion (3). A heat-conducting rubber (11) having a coefficient of thermal conductivity of not less than 0.3 W/(m·K) is disposed on the inner cavity surface (12) of the tire. At least part of said heat-conducting rubber (11) is disposed in a side-reinforcement rubber layer projection area (T) where the side-reinforcement rubber layer (9) is projected onto the inner cavity surface (12) of the tire.
Abstract:
In a pneumatic tire for heavy load in which a rubber chafer 8 is disposed at least in a part brought into contact with a rim in a bead part 1, the rubber chafer uses a rubber composition which comprises 45 to 55 parts by mass of butadiene base rubbers containing 10 to 30 parts by mass of a syndiotactic 1,2-structure-containing polybutadiene rubber and 45 to 55 parts by mass of a natural rubber as a rubber component and more than 50 parts by mass and less than 60 parts by mass of carbon black having DBP of 85 to 115 ml/100 g and a specific surface area by nitrogen adsorption (N2SA) of 50 to 100 m2/g based on 100 parts by mass of the rubber component.
Abstract:
A pneumatic tire construction is described suitable for severe loading conditions. The tire includes a bead portion further having an apex which extends radially outward of the bead core, and a turn-up pad located adjacent said chafer. The turn-up pad has a minimum specified width and a maximum specified width at a Radius R as measured from the bead center. The turn-up pad is formed of a material having a specified G′ and G″.
Abstract:
A rubber composition for a tire superior in low heat build-up (tan δ) and superior in fracture strength is provided. A rubber composition for a tire comprising (B) 5 to 80 parts by mass of silica based on 100 parts by mass of (A) including (a) 10 to 60% by mass of a butadiene rubber including 2.5 to 20% by mass of 1,2-syndiotactic polybutadiene crystals, (b) 5 to 60% by mass of a modified diene rubber and (c) 20 to 75% by mass of a diene rubber other than (a) and (b).
Abstract:
A pneumatic vehicle tire includes a carcass extending between two bead cores. A belt structure is provided between the carcass and a tread strip which is connected with a pair of sidewalls. A runflat reinforcement is arranged at the inner side of each sidewall. A reinforcer is arranged within each bead portion of the tire. A bead filler extends from the bead ring along the reinforcer. To improve the runflat performance, handling and comfort properties of such a runflat tire, the reinforcer is arranged at the inner side of the bead filler. The reinforcer includes metal cords. The bead filler which extends beyond an end of the reinforcer, is made of a soft rubber compound with an IHRD hardness lower than 80.
Abstract:
A tire having a circumferential tread, at least one belt, an inner liner, a pair of sidewalls, at least one carcass ply, and a pair of bead portions. The pair of bead portions each further includes a bead core, a bead filler having an upper end, a chaffer, and a gum strip. The chaffer extends axially outward from the inner liner towards the sidewall and curves radially upward along an axially outer portion of the bead core. The sidewall gum strip extends radially upward from a curved portion of the chaffer, wherein the sidewall gumstrip is located axially between the at least one carcass ply turn-up end and a sidewall.
Abstract:
A heavy-load tire has a wind bead structure in which a turned-up portion of a carcass ply is wound around a bead core, in which a bead portion is equipped with a bead reinforcing layer having a u-shaped cross section and a bead apex rubber having a triangular-shaped cross section. The turned-up portion has an auxiliary turned-up portion passing through the vicinity of a radially outer side of the bead core. The bead apex rubber includes a high elasticity inner apex portion disposed at a radially inner side and a low elasticity outer apex portion disposed at a radially outer side. The inner apex portion has an L-shaped cross section including a bottom piece portion along the radially outer side of the auxiliary turned-up portion, and a raised piece portion which rises at an axially inner end side of the bottom piece portion and extends radially outwardly in a tapering manner along the body portion of the carcass ply.
Abstract:
A subject-matter of the present invention is a rubber composition intended for the manufacture of tyres or of tyre semi-finished products, based on at least one isoprene elastomer, an inorganic filler as reinforcing filler and a polyfunctional organosiloxane coupling agent capable of providing the bonding between the reinforcing inorganic filler and the isoprene elastomer, comprising per molecule, grafted to its silicon atoms, on the one hand at least one hydroxyl or hydrolysable functional group allowing it to be grafted to the reinforcing inorganic filler and, on the other hand, at least one group bearing at least one azodicarbonyl functional group —CO—N═N—CO— allowing it to be grafted to the isoprene elastomer.
Abstract:
Accumulation of static electricity is prevented while enhancing rolling resistance performance of tire. Tread rubber 2G has tread rubber body 15 forming tread ground contact surface 2S, under tread 16 disposed radially inward of the tread rubber body, and terminal portion 17 penetrating the tread rubber body in the radial direction, the under tread 16 being in contact with cushion rubbers 13 each having cushion main portion 13A interposed between edge portion 7E of tread-reinforcing layer 7 and carcass 6 over an overlap width W1 of 1 mm or more. Tread rubber body 15, topping rubber 7G of tread-reinforcing layer 7 and sidewall rubbers 3G are made of an insulating rubber material 20 having a volume resistivity of at least 1×108 Ω·cm, and under tread 16, terminal portion 17, cushion rubber 13, topping rubber 6G of carcass 6 and chafer rubber 11 are made of a conductive rubber material having a volume resistivity of less than 1×108 Ω·cm.
Abstract:
A heavy-load tire comprises a tread portion, a pair of sidewall portions, a pair of bead portions each with a bead core therein, a carcass comprising a carcass ply of cords including a main portion extending between the bead cores, and a pair of turnup portions each turned up around the bead core from the axially inside to the outside of the tire, and an inner liner made from air-impermeable rubber and disposed on the tire internal cavity surface, wherein each bead portion includes a bead reinforcing layer with an L-shaped cross section, the bead reinforcing layer comprising an axially outer piece portion disposed along the axially outside the turnup portion and a bottom piece portion integral with the outer piece portion and terminating in a sub-core area between a first radial line extending inwards along the radial direction of the tire from an innermost axial point of the bead core, and a second radial line extending inwards along the radial direction of the tire from an outermost axial point of the bead core, the inner liner includes a radially inner portion that terminates radial inside than a lateral reference line passing through the innermost axial point and outermost axial point of the bead core, a rubber thickness ta is in a range of from 2.5 to 5.0 mm ranging from the tire internal cavity surface to the cord of the carcass ply on the lateral reference line, and an inner liner thickness tb is smaller than the rubber thickness ta and is in a range of from 0.5 to 3.0 mm on the lateral reference line.