A pneumatic tire for use on trucks, the tire comprising: a tread which includes a belt reinforcement structure, the belt structure including a pair of working belts, wherein the angle of the working belts range from about 10 degrees to about 50 degrees, and wherein the first working belt has an angle of the reinforcements different that the angle of the belt reinforcements of the second working belt. The belt package further includes a low angle belt that is preferably positioned between of the working belts, wherein the angle of the low angle belt is less than 5 degrees. The working belts and the low angle belt are extensible, and preferably made of high elongation wire. The pneumatic tire further includes a top protector belt made of high impact resistant steel reinforcements.

The tire comprises a crown reinforcing zone comprising a ply of strips, each forming an angle of less than or equal to 10° with the circumferential direction. Each reinforcing strip is formed by a laminate made up of n inner composite layers comprising low-modulus oriented fibres parallel to each other, the angle of which with the circumferential direction is, in absolute terms, less than or equal to 10°, together with m outer composite layers on either side of the inner composite layers, comprising high-modulus oriented fibres parallel to each other, the angle of which with the circumferential direction is, in absolute terms, strictly greater than 10°. The high- and low-modulus fibres are coated with a polymer matrix.

A method for designing a pneumatic tire to have improved vibration characteristics. Dynamic testing of the tire detects a) respective frequencies of a plurality of radial vibration modes of the tire, and b) respective frequencies of a plurality of torsional vibration modes of the tire. The testing may determine that a first interval between the frequency of an even-numbered radial vibration mode and the frequency of an even-numbered torsional vibration mode is less than a first threshold, and/or may determine that a second interval between the frequency of an odd-numbered radial vibration mode and the frequency of an odd-numbered torsional vibration mode is less than a second threshold. One or more design parameter of the tire is/are modified to increase at least one of first interval and the second interval to the respective first or second threshold.

A pneumatic tire includes cross belts and one or more protective belts provided in the tire radial direction. A width of a widest protective belt is greater than a width of any of the cross belts. In the tire profile, a maximum projection position of the widest protective belt is A, an end position of the widest protective belt is B, a position at which a straight line a passing through position A extending in the direction normal to a tread surface intersects with the tread surface is A′, and a position at which a straight line b passing through position B extending in the direction normal to the tread surface intersects with the tread surface is B′. An angle formed between a first straight line that links position A and position B and a second straight line that links position A′ and position B′ is from 0° to 15°.

A hooping reinforcement of a tire for a heavy duty civil engineering type vehicle is disclosed. The crown reinforcement (3) of the tire (1), radially on the inside of a tread (2), comprises a protective reinforcement (6), a working reinforcement (5) and a hooping reinforcement (7). Said hooping reinforcement (7) has an axial width at most equal to the smallest axial width (L61, L62) of the two working layers (61, 62), and comprises at least two hooping layers (71, 72) that are formed from strips each made up of elastic metal reinforcers. Each hooping layer (71, 72) is made up of an axial juxtaposition of contiguous turns of the strip (8), which are circumferentially wound around the working layer (51). Each strip (8) is at least 35 mm and at most 250 mm thick, and its distributed breaking tension is at least equal to 100 daN/mm.

A tire having a radial carcass reinforcement, made up of a single layer of reinforcing elements anchored in each of the beads by being turned up around a bead wire, reinforced by a stiffener. The two working crown layers are the only ones present to form the crown reinforcement over at least 75% of the width of the tread, the absolute value of the difference between the absolute values of the angles 2 and 1 being greater than 7, 2 being greater than 1 in terms of absolute value, the mean angle satisfying the relationship 13+131*exp(L/100)<<28+110*exp(L/100), the reinforcing elements of the carcass reinforcement being cords which, in the test referred to as the permeability test, yield a flow rate of less than 20 cm.sup.3/min, a rubber compound being present within the cords, and, in the sidewall of the tire, the profile of the outer surface of the tire is at a constant distance from the carcass reinforcement layer between the points F and A, and meets the outer surface of the bead at the point C, forming two successive circular arcs.

A cord (30) has a triple twist (T1, T2, T3) and comprises an assembly (25) consisting of N=3 strands (20a, 20b, 20c) twisted together with a twist T3 in a direction D2, each strand consisting of M=2 pre-strands, which are themselves twisted together with a twist T2 (T2a, T2b, T2c) in a direction D1 opposite to D2, each pre-strand itself consisting in a yarn that has been previously twisted about itself with a twist T1 in the direction D1, wherein each yarn consists of elementary monofilaments of aromatic polyamide or aromatic copolyamide. Each yarn has a count varying from 90 to 130 tex.

A pneumatic tire excellent in high speed stability and turning ability is provided. In a band of a tire, a center portion located in an axial center has a helically wound structure in which a first band body including a first cord is wound. A shoulder portion located on an axial outside of the center portion has a meshed structure formed by a second band body including a second cord. The shoulder portion includes a plurality of first portions, a plurality of second portions and a plurality of third portions. Each first portion is inclined and extends from an axially inner end of the shoulder portion to an axially outer end of the shoulder portion. Each second portion is inclined in an opposite direction from the first portion and extends from the axially inner end of the shoulder portion to the axially outer end of the shoulder portion.

A passenger vehicle pneumatic tire comprising: a carcass; and inclined belt layers and a circumferential belt layer, wherein: the inclined belt layers include at least two inclined belt layers having different tire widthwise widths; an inclination angle .sub.1 with respect to the tire circumferential direction of the cords forming the inclined belt layer having the widest width and an inclination angle .sub.2 with respect to the tire circumferential direction of the cords forming the inclined belt layer having the narrowest width satisfy correlations that 30.sub.185, 10.sub.230, and .sub.1>.sub.2; and a tire widthwise width W.sub.1 of the inclined belt layer having the widest width and a tire widthwise width W.sub.2 of the inclined belt layer having the narrowest width satisfy a correlation that W.sub.20.6W.sub.1.

A radial tire includes a pair of bead cores, a carcass layer having one or more carcass plies extending from one of the bead cores to another of the bead cores in a toroidal form, a tread portion circumferentially encircling the toroidal form of the carcass layer, and a belt layer having a main belt layer, a first, unreinforced cushion layer disposed on a radially outer side of the main belt layer, a protective belt layer disposed on a radially outer side of the first cushion layer, and a second, unreinforced cushion layer disposed on a radially outer side of the protective belt layer and a radially inner side of the tread portion. The first, unreinforced cushion layer has a radial thickness between 2.0 mm and 10.0 mm.