摘要:
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.
摘要:
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.
摘要:
A semi-finished product of elastomeric material includes a strip suitable for manufacturing an inner gas-impermeable coating layer of a pneumatic tyre. A right cross-section of the strip includes a profile that tapers axially outwards on at least one edge of the strip. A method for manufacturing a tyre for a vehicle wheel includes forming a layer of liner on a rigid support by laying at least one strip of elastomeric material on the rigid support in axially consecutive turns, laying other semi-finished products suitable for forming other components of the tyre in a radially outer position with respect to the layer of liner, and vulcanizing the layer of liner and other semi-finished products. The at least one strip includes a right cross section including the tapered profile. A tapered portion of a first turn is axially overlapped on an axially adjacent turn that was previously laid on the rigid support.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
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.
摘要:
During manufacture of a tyre for motor vehicles, one or more structural elements of elastomeric material, such as a tread band provided with a respective under-layer, are manufactured by laying a continuous elongated element on the carcass structure or other forming support, which elongated element is longitudinally divided into a first and second mutually-coupled portions that are obtained through extrusion of two different elastomeric materials coming from respective extruders leading to a common extrusion die. Laying of the coils takes place in such a manner that the first and second materials form a first layer and a second layer overlapping the first layer, respectively.