Patent classifications
B60C2009/208
Heavy goods vehicle tire with improved endurance
Heavy goods vehicle tire, having a crown portion covered radially on the outside by a tread, this tread having at least two cut-outs, the central portion of the tread having a width Lc of between 35% and 70%, the crown portion comprising a reinforcement having at least two working layers having reinforcing elements, these reinforcing elements consisting of UHT-grade threads, having a mechanical breaking strength R satisfying the following relation: R≥(4180−2130×D), where D is the diameter of the thread expressed in millimetres, this tread being formed of at least two layers of superimposed material, the material forming the first layer with a breaking elongation of more than 600% at a temperature of 60° C., this tread being such that, in the central portion, the cavity ratio per unit volume is not more than 10% and the surface cavity ratio as new is not more than 10%.
Crown Reinforcement of a Tire for a Heavy Construction Plant Vehicle
A tire (1) for a heavy construction plant vehicle with satisfactory compromise between the breaking strength of its circumferential hoop reinforcement (7), having an axial width LF and having a circumferential hooping layer (71, 72) with elastic metallic reinforcers having a structural elongation AS and a force at break FR, and forming an angle at most equal to 5° with the circumferential direction (XX), and the endurance of its working reinforcement (6), formed by two working layers (61, 62) with inextensible metallic reinforcers, the mean angle AM of which with the circumferential direction (XX′) is at least equal to 15° and at most equal to 45°. The axial width LF, the structural elongation As, the force at break Fr and the mean angle AM satisfy the relationship:
Zn/Z0*(T0+(a1+a2*As)/AM+b*LF*(AM−A0)/A0+c*AM)<Fr/CS, where Zn is the nominal load, Z0=100 t, T0=7000 N, a1=−230,000 N*°, a2=−160,000 N*°/%, b=−34,000 N/m, A0=29°, c=550 N/°, CS>=1.
Two-layer multi-strand cables having very low, low and medium modulus
A two-layer multi-strand cord (60) has a modulus EC such that 50 GPa≤EC≤160 GPa. The cord comprises: (a) an internal layer (CI) of the cord made up of J>1 internal strands (TI) wound in a helix having a modulus EI, each internal strand (TI) comprising: an internal layer (C1) made up of Q≥1 internal threads (F1), and an external layer (C2) made up of N>1 external threads (F2) wound around the internal layer (C1), and (b) an external layer (CE) of the cord made up of L>1 external strands (TE) wound around the internal layer (CI) of the cord, each external strand (TE) comprising: an internal layer (C1′) made up of Q′≥1 internal threads (F1′), and an external layer (C2′) made up of N′>1 external threads (F2′) wound around the internal layer (C1′).
GRC (glass-resin composite) monofilament
A monofilament made of glass-resin composite has improved properties in compression, in particular at high temperature, and comprises glass filaments embedded in a crosslinked resin. The glass transition temperature of the resin is equal to or greater than 190° C. The elongation at break of the monofilament, measured at 23° C., is equal to or greater than 4.0%. The initial tensile modulus of the monofilament, measured at 23° C., is greater than 35 GPa. The real part of the complex modulus of the monofilament, measured at 190° C. by the DMTA method, is greater than 30 GPa. Pneumatic or non-pneumatic tires are reinforced with such a composite monofilament.
Protective reinforcement comprising differentiated layers for a pneumatic tire for a heavy-duty civil engineering vehicle
A radial pneumatic tire for a heavy-duty civil engineering vehicle aims to reduce the risk of tread separation of the pneumatic tire, during driving on sharp rocks, while ensuring good resistance to cracking of the crown reinforcement. The pneumatic tire has a protective reinforcement with two protective layers, the radially innermost protective layer having elastic metal reinforcements with a diameter D1 which are axially distributed according to an axial pitch P1, and the radially outermost protective layer has elastic metal reinforcements with a diameter D2 which are axially distributed according to an axial pitch P2. In the tire the following relations are satisfied:
D1>D2
P1>P2
P1>=1.2*D1 and P2>=1.2*D2
2.5<=(D1*P1)/(D2*P2)<=5.
PNEUMATIC VEHICLE TIRE OF RADIAL DESIGN FOR UTILITY VEHICLE TIRES
A pneumatic vehicle tire of radial type of construction for utility vehicles, in particular trucks, buses and truck trailers, having a belt which has three or more belt plies (5, 6, 7, 8, 9) with steel cords (10), wherein each steel cord (10) has at least two strands (11) and wherein each strand (11) has at least two steel filaments (12); the invention is characterized in that steel cords (10) of the construction 2 to 4×N, where N=2 to 5, are at least arranged in one of the belt plies (5, 6, 7, 8, 9), wherein this construction means that this steel cord (10) has 2 to 4 twisted-together strands (11), wherein each strand (10) comprises 2 to 5 steel filaments (12) which are twisted together such that these 2 to 5 steel filaments (12) are arranged without a core filament.
TIRE WITH LOW ROLLING RESISTANCE AND METHOD FOR PRODUCING SAME
A tire comprises a crown reinforcement comprising: a working reinforcement comprising a single working layer and a hoop reinforcement arranged radially outside the working reinforcement and comprising at least one hooping filamentary reinforcing element (170) wound circumferentially helically so as to extend axially from one axial edge to the other axial edge of the hoop reinforcement. The or each hooping filamentary reinforcing element (170) consists of: two multifilament strands (1701, 1702) of aromatic polyamide or aromatic copolyamide and one multifilament strand (1703) of aliphatic polyamide or of polyester, or three polyester multifilament strands, each multifilament strand (1701, 1702, 1703) being wound in a helix around a main axis (W) common to the three multifilament strands (1701, 1702, 1703). The hoop reinforcement has a tangent modulus at 1.3% elongation ranging from 200 to 650 daN/mm.
Pneumatic tire
A pneumatic tire comprises a carcass layer, a belt layer disposed on an outer side of the carcass layer in a tire radial direction, and a tread rubber disposed on the outer side of the belt layer in the tire radial direction. The belt layer formed by laminating an angle belt having a belt angle≧45° and ≦70° in absolute values, a pair of cross belts, having belt angles of ≧10° and ≦45° in absolute values and having belt angles of mutually opposite signs, and a circumferential reinforcing layer having a belt angle within a range of ±5° with respect to a tire circumferential direction. A tread width TW and a total tire width SW such that 0.79≦TW/SW≦0.89. A width Ws of the circumferential reinforcing layer and a cross-sectional width Wca of the carcass layer such that 0.60≦Ws/Wca≦0.70.
Crown For Aircraft Tire
Tire for an aeroplane and, in particular, the crown thereof which comprises a tread (1), a textile crown reinforcement (2) and a textile carcass reinforcement (4). In order to optimize the number of landings, in the equatorial plane, the thickness (E1) of the tread is at least equal to 1.1 times the thickness of the working reinforcement and the thickness (E5) of the carcass is at least equal to 1.5 times the thickness (E3) of the working reinforcement, the reinforcing elements of the working layers (31, 32, 33) having a tenacity at least equal to 90 cN/tex.
RUBBER COMPOUND FOR TIRES, PNEUMATIC TIRE, AND AN AIRLESS TIRE
To provide a rubber compound for tires, a pneumatic tire and an airless tire capable of improving the steering stability of the tire while exerting excellent low fuel consumption performance. A rubber compound for tires characterized in that, of vulcanized rubber's physical properties, a complex elastic modulus E*.sub.70 (unit: MPa) and a loss tangent tanδ.sub.70 under initial strain of 10%, dynamic strain of 2% and temperature of 70 degrees C., satisfy 90<E.sub.70<250, and E*.sub.70/tan δ.sub.70>800. A pneumatic tire provided with a rubber member made of the above-mentioned rubber compound. An airless tire provided with a rubber member made of the above-mentioned rubber compound. An airless tire provided in a tread ring with a shear rubber layer made of the above-mentioned rubber compound.