Abstract:
A tyre for vehicle wheels has a pair of beads (5) each having a frusto-conical rest surface (5a) and showing a cross-section profile converging towards the rotation axis of the tyre (1) away from an equatorial plane (X-X) of same. Each bead (5) incorporates an annular anchoring structure (4) comprising an anchoring portion (16) of a flattened profile extending in parallel to the rest surface (5a), and a stiffening portion (12) extending in a radial direction. Associated with the carcass structure (2) is a circumferential centring ridge (20) radially jutting out within the tyre (1) at a crown portion of the latter. Also described is a rim (23) provided with engagement seats (24) the shape of which matches that of the beads (5) and with a guide race (25) conforming in shape to the centring ridge (20).
Abstract:
It is an object of the invention to provide a pneumatic tire and a producing method thereof capable of enhancing uniformity. A pneumatic tire 1 comprises a carcass which uses a carcass ply 10 in which a radially arranged carcass cord array is coated with topping rubber, and a tread. The carcass ply 10 includes a center ply portion 11 which is wound around the tread portion 2 in a circumferential direction of the tire and whose beginning end and terminating end in the circumferential direction of the tire are jointed to each other, and long rectangular ply portions 12 on opposite sides of the center ply portion 11. In each long rectangular ply portion 12, long rectangular pieces 12a formed by cutting the topping rubber by slits 13, and each long rectangular ply portion 12 is bent radially inward in accordance with shape of the sidewall portion 3 in a manner that adjacent long rectangular pieces 12a are superposed on each other, thereby forming a side portion 6S of the carcass.
Abstract:
A tire includes two beads and a carcass reinforcement anchored in the beads. The carcass reinforcement has at least two circumferential alignments of first reinforcing threads. Each such circumferential alignment is, within each bead, bordered axially inwardly and outwardly by second circumferential reinforcing threads having an elasticity modulus at least equal to that of the first threads. The first and second threads are separated by a rubber mix of high elasticity modulus. The outer surface of each bead includes a seat which includes an arc-shaped wall section having a geometrical center arranged axially outwardly relative to the bead. Considering an imaginary straight line passing through both the center and the bead at an angle α=+45±5 degrees relative to the tire axis, all of the second threads are spaced from that axis by a radial distance no larger than the locus of the imaginary line.
Abstract:
A self-supporting tire for vehicle wheels includes a carcass structure having at least one carcass ply, a belt structure, a tread band, at least one pair of sidewalls, and at least one pair of resilient stiffening inserts incorporated into the carcass structure. The at least one carcass ply includes axially-inner strip lengths and axially-outer strip lengths, and may also include axially-intermediate strip lengths. Each of the strip lengths extend in a U-shaped configuration around a cross-section outline of the carcass structure to define two side portions spaced apart from each other in an axial direction and a crown portion extending at a radially-outer position between the side portions. The resilient stiffening inserts are axially interposed between the side portions of the axially-inner strip lengths and the side portions of the axially-outer strip lengths.
Abstract:
A tire for vehicle wheels includes a carcass, a tread strip, and a belt structure. The carcass has a central crown portion and two axially opposite sidewalls terminating in a pair of beads. Each bead includes at least one circumferentially unextendable annular reinforcing core having a series of spirals of metal wire radially superimposed and axially arranged alongside each other. The carcass has a reinforcing structure including at least one ply of rubberized fabric reinforced with metal cords lying in radial planes containing an axis of rotation of the tire. The reinforcing structure includes ends secured to the annular reinforcing cores and a neutral profile, lying in a radial cross-sectional plane, axially extending from bead to bead. The neutral profile intersects a cross section of a zone enclosing the annular reinforcing cores and has a continuous curvature devoid of inflection points along an extension between the beads.
Abstract:
A tyre for a vehicle wheel includes a carcass structure, a belt structure, a tread band, and sidewalls. The carcass structure includes at least one first and second carcass ply and a pair of annular reinforcing structures. The carcass plies are formed of strip sections extending in a substantially U-shaped conformation, including at least two parallel thread elements at least partly coated with elastomer material. The at least one first (second) carcass ply includes a first (third) and second (fourth) series of strip sections arranged in mutually-alternating sequence along a circumferential extension of the carcass structure. The annular reinforcing structures include first and second primary portions. The first (second) primary portion includes an axially-inner side turned towards end flaps of the strip sections of the first (third) series and an axially-outer side turned towards end flaps of the strip sections of the second (fourth) series.
Abstract:
A tyre for a vehicle wheel includes a carcass structure, a belt structure, a tread band, and at least one pair of sidewalls. The carcass structure includes at least one circumferential centering ridge jutting out from a crown portion of the carcass structure. Each bead of the tyre includes a rest surface defining, in a direction away from an equatorial plane of the tyre, a profile converging toward the rotation axis of the tyre. A rim for a tyre includes a base body and two seats. Each seat defines an abutment surface facing radially away from a rotation axis of the rim and includes a frustoconical configuration converging away from a median diametrical plane of the rim. The base body further includes at least two opposite radial shoulders disposed to abut against the at least one centering ridge. A vehicle wheel, including the tyre and the rim, is also disclosed.
Abstract:
A pneumatic tire has such a bead portion structure that at least two bead wire structural bodies, each being obtained by spirally winding a bead wire(s) so as to continuously extend in a circumferential direction, are disposed in a bead portion so as to sandwich a carcass ply or enclose with the carcass ply, in which an outer end of at least one of the bead wire structural bodies in a radial direction is located on a position corresponding to a rim line or outward therefrom.
Abstract:
The anchoring of the carcass reinforcing elements 1 is assured by circumferential cables 2, with the interposition of a connecting rubber composition 3. The circumferential cable 2 is arranged in several turns forming one or more helices. These circumferential cables have an operational elongation rate AfnullAenullAp of more than 4%. This operational elongation rate does not include the specific elongation As of the nullcablenull effect. The maximum stress Rm of the cable 2 is preferably more than 2000 MPa. The cables have undergone a heat treatment which has, in combination, the features of being a recovery annealing treatment and which is carried out directly on cable comprising wires previously separately covered by an adherent coating.
Abstract:
A tire for vehicle wheels includes a carcass, a tread strip, and a belt structure. The carcass has a central crown portion and two axially opposite sidewalls terminating in a pair of beads. Each bead includes at least one circumferentially unextendable annular reinforcing core having a series of spirals of metal wire radially superimposed and axially arranged alongside each other. The carcass has a reinforcing structure including at least one ply of rubberized fabric reinforced with metal cords lying in radial planes containing an axis of rotation of the tire. The reinforcing structure includes ends secured to the annular reinforcing cores and a neutral profile, lying in a radial cross-sectional plane, axially extending from bead to bead. The neutral profile intersects a cross section of a zone enclosing the annular reinforcing cores and has a continuous curvature devoid of inflection points along an extension between the beads.