Abstract: Method, process and plant for building tires for vehicle wheels wherein: in a service position of a carcass structure building line, a forming drum is associated with a pair of support elements including a first support element and a second support element; the forming drum is moved, associated with the pair of support elements, in a deposition line in the carcass structure building line; and the forming drum is transferred from the deposition line to a subsequent work station of the carcass structure building line.

Abstract: A robot arm having seven axes of actuation imparts to a toroidal support a circumferential distribution motion about its own geometric axis simultaneously with controlled transverse distribution displacements in front of a dispensing organ of a strip of elastomeric material. The strip thus forms a plurality of turns, the orientation and mutual superposition whereof are controlled in such a way as to control the thickness variations to be conferred to a component of a tire being manufactured, based on a pre-determined laying scheme pre-set on an electronic computer. The rotation of the toroidal support is controlled in such a way as to obtain a peripheral speed of application exceeding the theoretical feeding rate of the strip, able to be increased or decreased as needed to form turns with reduced or, respectively, enlarged cross section.

Abstract: A robot arm having seven axes of actuation imparts to a toroidal support a circumferential distribution motion about its own geometric axis simultaneously with controlled transverse distribution displacements in front of a dispensing organ of a strip of elastomeric material. The strip thus forms a plurality of turns, the orientation and mutual superposition whereof are controlled in such a way as to control the thickness variations to be conferred to a component of a tyre being manufactured, based on a pre-determined laying scheme pre-set on an electronic computer. The rotation of the toroidal support is controlled in such a way as to obtain a peripheral speed of application exceeding the theoretical feeding rate of the strip, able to be increased or decreased as needed to form turns with reduced or, respectively, enlarged cross section.

Abstract: Method, process and plant for building tires for vehicle wheels wherein: in a service position of a carcass structure building line, a forming drum is associated with a pair of support elements including a first support element and a second support element; the forming drum is moved, associated with the pair of support elements, in a deposition line in the carcass structure building line; and the forming drum is transferred from the deposition line to a subsequent work station of the carcass structure building line.

Abstract: Method, process and plant for building tires for vehicle wheels wherein: in a service position of a carcass structure building line, a forming drum is associated with a pair of support elements including a first support element and a second support element; the forming drum is moved, associated with the pair of support elements, in a deposition line in the carcass structure building line; and the forming drum is transferred from the deposition line to a subsequent work station of the carcass structure building line.

Abstract: An expandable bladder has at least one first layer of butyl material and one second layer of silicone material, radially external to the first layer. The first and second layers have an undulated interface profile defining mechanical-engagement elements between the first and second elastomer materials. A process for manufacturing bladder as well as a tire molding and vulcanizing apparatus incorporating the bladder.

Abstract: Method, process and plant for building tires for vehicle wheels wherein: in a service position of a carcass structure building line, a forming drum is associated with a pair of support elements including a first support element and a second support element; the forming drum is moved, associated with the pair of support elements, in a deposition line in the carcass structure building line; and the forming drum is transferred from the deposition line to a subsequent work station of the carcass structure building line.

Abstract: An expandable bladder has at least one first layer of butyl material and one second layer of silicone material, radially external to the first layer. The first and second layers have an undulated interface profile defining mechanical-engagement elements between the first and second elastomer materials. A process for manufacturing bladder as well as a tyre moulding and vulcanising apparatus incorporating the bladder.

Abstract: An expandable bladder has at least one first layer of butyl material and one second layer of silicone material, radially external to the first layer. The first and second layers have an undulated interface profile defining mechanical-engagement elements between the first and second elastomer materials. A process for manufacturing bladder as well as a tire molding and vulcanising apparatus incorporating the bladder.

Abstract: A method for manufacturing a tire includes making at least one semi-finished elementary product of elastomeric material and depositing it in adjacent turns on a toroidal support. Making the at least one elementary product includes extruding the elastomeric material through an extruder head including a bushing defining a tapered extrusion channel. An extruder includes a chamber, at least one helical screw disposed in the chamber, and the extruder head. The head includes an outer tubular body attached by one end to the chamber, a bushing disposed inside the body to define the tapered extrusion channel, and a die disposed inside the body. A ratio of an area of the inlet section to an area of the outlet section is greater than 5:1 and less than 100:1 and a ratio of a diameter of the inlet section to a length of the bushing is greater than 0.1 and less than 1:1.

Abstract: A vehicle wheel tire includes a carcass structure, at least one annular reinforcing structure, a tread band, and a pair of sidewalls. The carcass structure includes at least one carcass ply, each including a plurality of elongated elements disposed around a cross-section profile of the tire. Each elongated element includes two side portions at mutually-spaced-apart positions and a crown portion that extends between the side portions. The at least one annular reinforcing structure includes at least one bead core. A fraction of the elongated elements is turned up around the at least one bead core. A method of manufacturing the tire includes preparing the elongated elements, disposing each elongated element on a toroidal support, applying at least one bead core at a region close to side portions of the elongated elements, and turning up ends of a fraction of the elongated elements around the at least one bead core.

Abstract: In a tyre for vehicle wheels, the tread band sidewalls and/or other structural elements of elastomer material have a layered structure which includes at least one first component and at least one second component of a material with different composition from that of the first component. The first and second components have an undulated interface profile, defining elements of mutual mechanical engagement. Also described is a process and an apparatus for manufacturing a tyre.

Abstract: One or more components of elastomer material in a tyre are formed by dispensing elastomer material through a nozzle of an extruder to form a continuous elongated element of flattened section that is laid in the form of coils disposed close to each other on a laying surface carried by a support element, while said support element is driven in rotation and suitably moved adjacent to a die of the nozzle. The nozzle is drivable in rotation by an actuator so as to modify orientation of the nozzle itself during formation of the tyre component.

Abstract: A method for manufacturing a reinforcing structure for tires of vehicles includes the steps of preparing a plurality of strip segments having substantially parallel, longitudinal filiform elements at least partially coated by at least one layer of elastomeric material, and applying the plurality of strip segments along a circumference of a toroidal support, to form at least one continuous reinforcing layer about a geometric axis of rotation of the toroidal support. During the applying step, a relative angular rotation, between at least one of the plurality of strip segments and the toroidal support, occurs about an axis of correction substantially radial to the geometric axis of rotation. A related apparatus for manufacturing a reinforcing structure for tyres of vehicles is also disclosed.

Abstract: An expandable bladder has at least one first layer of butyl material and one second layer of silicone material, radially external to the first layer. The first and second layers have an undulated interface profile defining mechanical-engagement elements between the first and second elastomer materials. A process for manufacturing bladder as well as a tyre moulding and vulcanising apparatus incorporating the bladder.

Abstract: A method for producing a tyre for a vehicle wheel includes disposing a carcass structure on a drum having distal and proximal halves; disposing a belt structure around the carcass structure; moving the distal and proximal halves mutually close, from a building condition to a shaping condition, until an intermediate portion of the carcass structure contacts an inner surface of the belt structure; and transferring the drum, in the shaping condition, to a vicinity of at least one application unit. The distal and proximal halves are both carried by a support structure. During moving the distal and proximal halves mutually close, the proximal half maintains a fixed axial position with respect to the support structure. The at least one unit applies at least one elongated element of elastomeric material, in circumferential coils, to form at least one component of the tyre external to the carcass structure.

Abstract: An expandable bladder has at least one first layer of a natural or synthetic rubber-based material or a mixture thereof, and one second layer of silicone material, radially external to the first layer. The first and second layers have an undulated interface profile defining mechanical-engagement elements between the first and second elastomer materials. A process for manufacturing a bladder as well as a tyre manufacturing apparatus incorporating bladders is also disclosed.

Abstract: A vehicle wheel tyre includes a carcass structure, at least one annular reinforcing structure, a tread band, and a pair of sidewalls. The carcass structure includes at least one carcass ply, each including a plurality of elongated elements disposed around a cross-section profile of the tyre. Each elongated element includes two side portions at mutually-spaced-apart positions and a crown portion that extends between the side portions. The at least one annular reinforcing structure includes at least one bead core. A fraction of the elongated elements is turned up around the at least one bead core. A method of manufacturing the tyre includes preparing the elongated elements, disposing each elongated element on a toroidal support, applying at least one bead core at a region close to side portions of the elongated elements, and turning up ends of a fraction of the elongated elements around the at least one bead core.

Abstract: A method for manufacturing a tyre includes making at least one semi-finished elementary product of elastomeric material and depositing it in adjacent turns on a toroidal support. Making the at least one elementary product includes extruding the elastomeric material through an extruder head including a bushing defining a tapered extrusion channel. An extruder includes a chamber, at least one helical screw disposed in the chamber, and the extruder head. The head includes an outer tubular body attached by one end to the chamber, a bushing disposed inside the body to define the tapered extrusion channel, and a die disposed inside the body. A ratio of an area of the inlet section to an area of the outlet section is greater than 5:1 and less than 100:1 and a ratio of a diameter of the inlet section to a length of the bushing is greater than 0.1 and less than 1:1.

Abstract: A tyre for a vehicle wheel includes a carcass structure, a pair of annular reinforcing structures, a tread band, and a pair of sidewalls. The carcass structure includes at least one carcass ply including two lateral portions and a crown portion. The at least one carcass ply comprises elongated elements arranged in a substantially U-shaped configuration around a profile of a cross-section of the tyre. A density of the elongated elements is greater in the lateral portions than in the crown portion. The density of the elongated elements increases continuously and regularly in end zones of the lateral portions in directions away from the crown portion. A shape of a cross-section of each elongated element is constant. A method for forming the tyre includes preparing a plurality of strip elements, constricting end zones of each strip element, and laying the strip elements with constricted end zones on a toroidal support.