Pirelli Pneumatici S.p.a.

Pirelli Coordinamento Pneumatici S.p.a.

Guido Riva

Gurdev Orjela

Alessandro Volpi

Syed Khawja Mowdood

Claudio Villani

Maurizio Boiocchi

Marco Cipparrone

Cèline Almonacil

Giancarlo Armellin

Guido Luigi Daghini

Stefano Bizzi

Giancarlo Cucco

Luca Frisiani

Gian Carlo Cucco

Piero Misani

A tire includes a carcass, a belt structure, and a tread band. The belt structure includes at least two belt plies and at least one belt layer radially external to the belt plies. The at least one belt layer extends at least for an axial width of the at least two belt plies and includes at least one first elongated element and at least one second elongated element. The elongated elements form turns substantially oriented in a circumferential direction of the tire. The turns are alternately disposed along an axial development of the at least one belt layer. The at least one first elongated element is a hybrid cord including at least one high-elastic-modulus filament and at least one low-elastic-modulus filament that are twisted together. An elastic modulus of the at least one second elongated element is lower than an elastic modulus of the at least one first elongated element.

Tyre with specified belt structure

A process for manufacturing a tire includes providing an elastomeric layer on an outer surface of a toroidal support, manufacturing the tire on the toroidal support provided with the elastomeric layer, introducing the tire supported on the toroidal support into a moulding cavity, introducing a fluid under pressure into a space defined between the toroidal support and an inner surface of the tire in order to press an outer surface of the tire against walls of the moulding cavity, and curing the tire. The elastomeric layer forms an inner circumferential surface of the tire. The process further includes causing an electrical current to flow in at least one heating element provided to the outer surface of the toroidal support so as to obtain at least partial precuring of the elastomeric layer. A toroidal support for carrying out the process is also disclosed.

Process for manufacturing a tyre and toroidal support for carrying out the process

A tire for a vehicle wheel includes a carcass structure, a tread band extending circumferentially around the carcass structure, a belt structure circumferentially located between the carcass structure and the tread band, and at least one pair of sidewalls applied to the carcass structure in axially opposite positions. The carcass structure includes at least one carcass ply. Ends of the carcass structure are fastened to a pair of annular reinforcing elements, wherein each annular reinforcing element is incorporated in a respective bead of the tire includes at least one cord. The at least one cord includes at least one preformed metallic thread element.

Annular reinforcing element for a tyre and tyre including the annular reinforcing element

A tire for a vehicle wheel includes at least one metallic reinforcing cord comprising a single strand of elementary filaments preformed by sinusoidal waving and wound together. The number of filaments is greater than or equal to 3 and less than or equal to 8. A diameter of each filament is greater than or equal to 0.12 mm and less than or equal to 0.35 mm. A linear density of the at least one reinforcing cord is greater than or equal to 0.18 g/m and less than or equal to 4.0 g/m. A value of a breaking-stress integral of the at least one reinforcing cord is greater than or equal to 5,000 J/m. In a two-wheeled vehicle, the at least one reinforcing cord in a tire for front-mounting may be distributed with a variable density while, in a tire for rear-mounting, the density may be constant.

Tire for a vehicle wheel comprising at least one single strand metallic reinforcing cord

A method of mounting a tire on a rim includes selecting a tire comprising bead cores, stretching the bead cores, sliding the bead cores over a balcony portion of the rim, allowing the bead cores to elastically return to lengths corresponding to diameters of respective seats of the rim, and inflating the tire. The bead cores include one or more portions of material with characteristics of superelasticity and shape memory. Stretching the bead cores may include applying constant load to the bead cores at ambient temperature and/or causing the bead cores to undergo structural change at ambient temperature. The structural change may include complete or partial change from austenitic structure to martensitic structure. The one or more portions of material are deformable at ambient temperature in response to a constant force and recover to original shape upon removal of the constant force.

Method of mounting a tire on a rim

A rubberized fabric for a tire belt includes an elastomeric material and at least one reinforcing metal strap in the elastomeric material. The at least one reinforcing metal strap is made of a shape-memory material. The at least one reinforcing metal strap is oriented at about 0&#xb0; to an equatorial plane of the tire. The at least one reinforcing metal strap has a width of no less than about 1 mm. The at least one reinforcing metal strap has a first thickness of no greater than about 0.1 mm. The at least one reinforcing metal strap may have coils disposed side-by-side and axially displaced from one another.

Rubberized fabric with reinforcing metal strap made of a shape-memory material

A tire for a vehicle wheel, capable of withstanding the load at low pressure or zero pressure, includes a carcass, a crown, two axially opposed sidewalls, two bead cores, two compression-resistant annular reinforcing elements, and, optionally, a belt structure. The annular reinforcing elements are made of material having high rigidity and very low elastic hysteresis. Each annular reinforcing element is in or adjacent to a zone joining the crown to a sidewall and in a first plane parallel to an equatorial plane of the tire. Each bead core is in a second plane parallel to the equatorial plane. The distance between the first planes is greater than or equal to the distance between the second planes. A camber of an arc between a bead core and an intersection of a carcass ply line with a cylindrical surface passing through the reinforcing elements does not exceed 15% of the arc length.

Tire for a vehicle wheel capable of withstanding the load at low pressure or zero pressure

A bead core for locking a tire to a seat of a wheel rim includes a plurality of annular reinforcement elements having an inner transverse dimension smaller than a maximum diameter of the wheel rim, and being sufficiently deformable at ambient temperature to facilitate mounting the tire onto the wheel rim. The plurality of annular reinforcement elements includes at least one tightening element made of a shape-memory alloy responsive to temperature increases by increasing a tightening force on the wheel rim at a predetermined temperature. A tire including the bead core and a method for securing a tire to a rim using the bead core are also disclosed.

Tire bead core assembly and tire using the same

A tire includes a carcass, a tread band, at least a reinforcing belt between the tread band and the carcass, a pair of bead cores disposed one at each end of the carcass with ends of the carcass wrapped around the pair of bead cores to form a pair of beads, and at least one clamp disposed around each bead core, wherein the at least one clamp is made of a shape-memory material. A bead core including at least one clamp made of a shape-memory material, a method for manufacturing a tire including at least one clamp made of a strip of shape-memory material, and a method for manufacturing a bead core including at least one clamp made of a strip of shape-memory material are also disclosed.

Bead core with a clamp, tire incorporating same, and method of making same

A tire includes a toroidal carcass and a tread band. The toroidal carcass includes a central crown and two sidewalls terminating in a pair of annular beads. Each annular bead includes a metallic bead core for anchoring to corresponding bead seats of a wheel rim. The metallic bead cores include at least one annular portion made of a material having characteristics of superelasticity and shape memory. The material having characteristics of superelasticity and shape memory is deformable at ambient temperature in response to a constant force and recovers to an original shape upon removal of the constant force to facilitate mounting the tire on the wheel rim. The wheel rim includes a central cylindrical channel from which branches off, axially and outwardly, from opposite sides, diverging surfaces each terminating in a peripheral flange. The diverging surfaces form the bead seats for respective annular beads of the tire.

Tire comprising bead core material having characteristics of superelasticity and shape memory

Metal cord for use in reinforcing fabric for articles made from rubber, such as pneumatic tires, conveyor belts, flexible tubes, and similar, comprising a plurality of such metal cords orientated parallel to each other in a single direction and in which each cord comprises metal wires wound spirally around each other, wherein at least one of the wires of the cord consists of a shape memory material. During the phase of incorporation of the cords into the elastomeric material, the shape memory wire tends to recover the shape memorized initially and, by means of the force generated during this recovery, transmits by friction to the surrounding wires forces tending to shorten the pitch of the cord with spacing of each wire from the next, resulting in good penetration of elastomeric material between the wires. The closure of the cord is maintained in the subsequent heat cycles, owing to the memory degradation characteristics imparted to the wire. The invention is particularly suitable for fabrics forming belt layers and casing plies in pneumatic tires.

Shape memory cords for reinforcing articles made from elastomeric material

A tire includes a carcass; a tread band on the carcass; a belt, positioned between the tread band and the carcass, including at least one layer of rubberized fabric; and at least one reinforcing metal strap in the at least one layer of rubberized fabric. The at least one reinforcing metal strap is made of a shape-memory material oriented at about 0&deg; to an equatorial plane of the tire. The at least one reinforcing metal strap has a width of no less than about 1 mm. And the at least one reinforcing metal strap has coils disposed side-by-side in a direction substantially perpendicular to a radius of the tire.

Tire with zero-degree, metal reinforcing strap made of a shape-memory alloy

A metal cord for reinforcing articles made from elastomeric material comprises a plurality of metal wires wound spirally around each other. At least one of the metal wires is formed from a shape memory material, has capacities of recovering a previously memorized shape, and is deformed from the memorized shape. The shape memory wire of the cord has the recovery capacities substantially active in a first heat cycle and degraded to at least a significant predetermined extent after the first heat cycle. One or more such metal cords may be incorporated in pneumatic tires, reinforcing fabric, and other articles, including by means of processes described herein.

Growing community of inventors

Milan, Italy

Guido Riva