Abstract: An apparatus for manufacturing tread bands for vehicle tires includes at least one primary extrusion head, a preforming device, at least one auxiliary extrusion head, an auxiliary feeding channel, and an extrusion die. The preforming device includes a primary preforming channel operatively connected to the at least one primary extrusion head. The auxiliary feeding channel is operatively connected to the at least one auxiliary extrusion head. The auxiliary feeding channel connects to the primary preforming channel. A direction of the auxiliary feeding channel forms an angle between approximately 30° and 160° relative to a direction of the primary preforming channel. The extrusion die is connected to the preforming device and includes an extrusion outlet. The auxiliary feeding channel connects to the primary preforming channel substantially near the extrusion outlet.

Abstract: A high-transverse-curvature tire (1), in particular to be mounted on the front wheel of a motor-vehicle, which includes a belt structure (6) including, in a radially external layer (9a), a plurality of circumferential coils (7a), axially arranged side by side, of a cord (7) wound at a substantially zero angle with respect to the equatorial plane (X—X) of the tire. An area occupied by rubber blocks (10) formed in a portion of the tread band (8), having a length equal to the pitch (p) of the tread pattern and a width equal to the axial development of the tread band (8), is between 70% and 90% of the total area of the portion.

Abstract: A tire (1) having sidewalls (3) with an annular strip (8) within which a plurality of ribs (9) is formed. The ribs are disposed in mutual side by side relation and circumferentially distributed. The annular strip (8) is made in the form of a hollow on a sidewall (3) of the tire (1) and is designed to display informative inscriptions (12) the characters of which (13) are defined by projections (19) projecting from the surface of the annular strip.

Abstract: A tire for a two-wheeled vehicle includes a carcass of toric form having a high transverse curvature, a tread band, and a circumferentially-inextensible belt structure. The belt structure is interposed between the carcass and the tread band, and includes reinforcing elements. Relative to an equatorial plane of the tire, the reinforcing elements may be randomly oriented, substantially oriented in an axial direction, or substantially oriented in an inclined direction. The belt structure further includes a radially-external layer provided with a plurality of cord coils disposed at a substantially-zero angle relative to the equatorial plane of the tire. The cord coils are positioned in axial side-by-side relationship and extend from one axial extremity of the belt structure to an opposite axial extremity. A density of the cord coils grows from the equatorial plane of the tire to the axial extremities of the belt structure.

Abstract: A rubberized reinforcing fabric for articles made from elastomeric material includes a plurality of textile cords having at least tensile strength, parallel and adjacent to each other in a same direction, and incorporated in an elastomeric material The cords have a count between 420/2 dTex and 840/2 dTex, a diameter between 0.33 mm and 0.47 mm, and are embedded in the fabric. The fabric has a thickness of not more than 0.8 mm and a density between 125 cords/dm and 280 cords/dm. The cords constitute a maximum of 40% of a volume of the fabric. An article made from elastomeric material, including at least one rubberized reinforcing fabric made from elastomeric material, is also disclosed.

Abstract: A method for reducing the working temperature of a tire tread for vehicles utilizing a tire tread comprising a first portion and a second portion. The first portion comprising 100 parts by weight of an elastomeric material, 40-120 parts by weight of a filler, comprising from 50 to 100% by weight of carbon black and from 0 to 50% of silica, and 3-40 parts by weight of at least a conventional additive. The second portion comprising 100 parts by weight of an elastomeric material, 40-120 parts by weight of a filler, comprising from 30 to 100% by weight of silica and from 0 to 70% of carbon black, and 3-40 parts by weight of at least a conventional additive. However, the silica content in the second portion is at least 20% higher than in the first portion. Tires wherein the area of the first portion exceeds 37.1% of the total area of the tire tread are also disclosed.

Abstract: A front tire for two-wheeled vehicles comprising a carcass of toric form having a high transverse curvature and provided with a central crown and two sidewalls terminating in a pair of beads for anchoring to a corresponding mounting rim, a tread band located on the crown and a circumferentially-inextensible belt structure disposed between the carcass and tread band. The belt structure at a radially external position is comprised of a layer of cord coils substantially disposed at a zero angle to the equatorial plane of the tire in axial side-by-side relationship and extended from one axial extremity of the belt to the other axial extremity of the belt. The winding thickness of the cord coils increasingly grows from the equatorial plane to the belt axial extremities.

Abstract: A tyre includes a tread band having at least two substantially parallel longitudinal grooves and at least one series of transverse grooves crossing the longitudinal grooves. The transverse and longitudinal grooves delimit at least two rows of shoulder blocks and at least one row of centre blocks. The transverse grooves have at least two transverse channels, each including an outer end stretch in an orientation substantially perpendicular to an equatorial plane of the tyre and a curvilinear connecting stretch close to the equatorial plane. The joining of laterally-opposite transverse channels gives each transverse groove a continuous course. At least one transverse channel of at least one of the transverse grooves also includes an inner end stretch. The connecting stretch interconnects the outer end stretch with the inner end stretch in a continuity relationship.

Abstract: A tread band for vehicle tires is manufactured by conveying a primary elastomer material (4) through an extrusion path (11, 15) defined by a preforming channel (15) followed by an extrusion outlet (11) formed in a die (10). The preforming channel (15) is defined in a preforming device (9) comprising a drawer (12) operatively engaging a preformer (13). Formed in the drawer (12) is an auxiliary channel (17) the end length (17b) of which opens at right angles into the extrusion path (11, 15), close to the extrusion outlet (11). An auxiliary elastomer material (5) conveyed to the auxiliary feeding channel (17) is homogeneously distributed by a coating effect under the lower surface of the tread band (4a) crossing the extrusion outlet (11).

Abstract: A pair of high-transverse-curvature tires, in particular for equipping a two-wheeled vehicle, in which the belt structure of the rear tire comprises a layer of inextensible cords disposed at a substantially zero angle with respect to the equatorial plane of the tire, preferably wound on a sheet of elastomeric material reinforced with aramide pulp, whereas the belt structure of the front tire comprises at least one radially outer layer of inextensible cords disposed at a substantially zero angle with respect to the equatorial plane of the tire and distributed with an axially variable density, and preferably, another reinforcing layer at a radially underlying position.

Abstract: A vulcanizable rubber composition is described comprising a cross-linkable unsaturated chain polymeric base, wherein is incorporated at least one organic compound, solid at room temperature, selected from the group comprising: amorphous or semicrystalline polymers, oligomers, low-molecular weight organic substances and mixtures thereof, which compound is substantially insoluble in the polymeric base and shows a first or second order transition temperature of from 80 to 160° C. Such rubber composition allows the manufacture of treads with either a low rolling resistance at the temperature of normal use of the tire (40°-70° C.), or a high grip when the tread is subjected to thermal stresses exceeding such temperatures.

Abstract: A pair of high-transverse-curvature tires for two-wheeled vehicles is provided, in which the belt structure of the rear tire comprises a layer of inextensible cords disposed at a substantially zero angle with respect to the equatorial plane of the tire whereas the belt structure of the front tire comprises at least one radially outer layer of inextensible cords disposed at a substantially zero angle with respect to the equatorial plane of the tire and distributed with an axially variable density. In the belt structure of the front tire the distribution density of the cords preferably continuously increases from the center to the belt ends, starting at the ends from a value of about 6 cords/cm at an area of a width included between 10% and 30% of the axial extension of the belt disposed on either side of the equatorial plane.

Abstract: 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.

Abstract: At least one metal wire embedded in a vulcanized elastomeric matrix obtained from a mixture comprising at least one vulcanizable elastomer and at least one vulcanization agent such as sulfur. The metal wire is galvanized steel and the vulcanizable mixture contains at least 0.2% by weight of trimercapto triazine, with respect to the weight of said elastomer, and 0.1-0.5% by weight of cobalt, with respect to the weight of said elastomer.

Abstract: A mold for tire vulcanization that includes axially opposite sidewalls and a tread band molded with a raised pattern formed with at least one circumferential groove. The mold has a pair of axially opposite cheeks corresponding to the sidewalls of the tire and a matrix interposed between the cheeks, which corresponds to the tread band. The matrix has a plurality of ribs projecting in a raised configuration from a bottom surface. The sectional profile of the bottom surface comprises two distinct concave side portions and the sectional profile of the surface tangent to the ridge of the ribs in the area included between the side portions has a convexity directed radially inwardly.

Abstract: A vehicle tire is made by inflating a vulcanized air tube to a slight pressure. Then, at least one thread element is wound around the transverse profile of the air tube to form a first carcass ply consisting of turns disposed consecutively in side-by-side relationship. A pair of annular anchoring elements is applied to the first carcass ply. Then, a second carcass ply is formed by winding at least one thread element so as to form turns disposed consecutively in side-by-side relationship along the circumferential extension of the air tube. Associated with the carcass structure is an annular element made up of a belt structure and a tread band. The carcass structure and annular element can be vulcanized separately from each other to make a tire having a tread band susceptible of replacement together with the belt structure.

Abstract: Mould parts of a mould for vehicle tyres, such as sector matrices in a centripetal mould, are made by sintering of a metal- or ceramic-based powder (3) cyclically deposited in consecutively superposed layers. Deposition of each layer is followed by sintering of the powder by a laser beam (8) moving within previously defined areas delimiting contours of the sintered laminate portion thus obtained. Movement of the laser beam (8) is managed by a programmable electronic control unit (11) in which digital information defining the three-dimensional graphic representation of the mould portion to be obtained is stored. The digital information is processed for dividing the graphic representation into superposed layers corresponding each to one of the laminate portions to be obtained by sintering of the corresponding powder layer. Thus moulds of sintered material are obtained, which are provided with inner microcavities enabling air ejection during the tyre vulcanization.

Abstract: A tire for a wheel of a vehicle comprises a toroidal carcass provided with axially opposite sidewalls and beads for anchoring the tire to a rim of the wheel, a tread band located crownwise on the carcass, comprising a surface with a plurality of hollows and grooves defining a raised tread pattern, and a belt structure interposed between the carcass and the tread band, axially extending between the sidewalls. The tread band comprises at least first and second circumferential axially-contiguous portions arranged to contact a road surface. The first portion is formed of a first composition comprising a reinforcing filler having at least 40%-by-weight carbon black and at least some white filler, the second portion is formed of a second composition comprising a reinforcing filler having at least 20%-by-weight white filler, and the first composition is different from the second composition.

Abstract: Reinforcing fabric for articles made from elastomeric material, particularly for pneumatic tires, comprising a plurality of filamentary elements having at least tensile strength, parallel and adjacent to each other in a plane, lying in a predetermined direction. The reinforcing elements, preferably cords, are incorporated in an elastomeric material and constitute at most the 40% of the volume of the fabric.

Abstract: In a tire for motor-vehicles, an auxiliary support element (9) is interposed between a carcass ply (3) and a belt structure (6). The support element is employed during the manufacturing step of the belt structure (6) in order to stably retain, on the sectors of a comb drum (10), coils (7a) consecutively formed by winding of an inextensible cord (7) therearound. The auxiliary support element (9) is made in the form of an elastomeric sheet containing short aramid fibers in an amount included between 1 and 10 parts by weight per 100 parts of elastomeric material, to increase the stretchability of said element without impairing its adhesiveness. The introduction of the short aramid fibers in the blend enables the thickness of the auxiliary support element (9) to be reduced to about 0.075 mm.