B60C9/0007

Pneumatic tire
10821779 · 2020-11-03 · ·

A pneumatic tire comprises a carcass layer, a belt layer disposed on the outer side in the tire radial direction of the carcass layer, and tread rubber disposed on the outer side in the tire radial direction of the belt layer. The belt layer is formed by laminating a pair of cross belts having belt angles with an absolute value from 10 to 45 both inclusive and mutually opposite signs, and a circumferential reinforcing layer having a belt angle within a range of 5 relative to the tire circumferential direction. The distance (Gcc) from the tread profile to the tire inner circumferential surface along the tire equatorial plane and the distance (Gsh) from the tread edge to the tire inner circumferential surface have a relationship satisfying 1.10Gsh/Gcc. The groove depth (Dsh) and under-groove gauge (UDsh) of the outermost circumferential main groove have a relationship satisfying 0.20UDsh/Dsh.

TIRE

A tire includes a steel cord having a plated coating layer, rubber covering the steel cord, the plated coating layer including Cu and Zn, and a bonding layer including Cu.sub.2S and CuS provided closer to the rubber than an interface between the steel cord and the rubber, wherein a molar ratio Cu.sub.2S/CuS of Cu.sub.2S and CuS included in the bonding layer is 1.0 or higher.

Tyre for wheels of heavy transport vehicles

A tyre includes a carcass structure including at least one carcass ply, a belt structure applied in a radially outer position with respect to the carcass structure, and a tread band applied in a radially outer position with respect to the belt structure. The belt structure includes two main belt layers and first and second reinforcing strips incorporating a plurality of reinforcing elements arranged substantially in the circumferential direction. The reinforcing elements include at least one high-elongation metal cord including a plurality of intertwined strands, and each strand includes a plurality of filaments. Each filament has a diameter not greater than 0.175 mm.

STRAIGHT PLY AND ANGLE PLY COMPRISING METALLIC MONOFILAMENTS

A ply (16, 18) comprises metallic monofilaments (46, 46). Each monofilament (46) of a first group has a positive torsional elastic deformation in a first direction about its main axis (G). Each monofilament (46) of a second group has a negative torsional elastic deformation in a second direction about its main axis (G). The absolute value of the torsional elastic deformation C of each monofilament (46, 46) is such that |C|6 turns per ten metres. The mean S of the torsional elastic deformations of the monofilaments (46, 46) of the ply (16, 18) is such that 0.25 turn per ten metresS+0.25 turn per ten metres. The monofilaments (46, 46) are arranged next to one another so as to alternate one or more monofilaments (46) of the first group with one or more monofilaments (46) of the second group.

Tire Comprising Working Layers Including Monofilaments For Preventing Cracking

Technique to increase the endurance of tires comprising two crossed working layers (41, 42), comprising mutually parallel reinforcing elements (411, 421) forming, with the circumferential direction (XX) of the tire, an angle at least equal to 20 and at most equal to 50, the reinforcing elements being made up of individual metal threads or monofilaments having a cross section at least equal to 0.20 mm and at most equal to 0.6 mm. The end of the monofilaments comprises flats such that they reduce the shear forces in the rubber compounds of the tire under compressive loading.

RUBBER COMPOSITION, METAL-RUBBER COMPOSITE, AND TIRE
20200308367 · 2020-10-01 · ·

An object of the present disclosure is to provide a rubber composition possessing both satisfactory low exothermic property and satisfactory durability in adhesion to metal, crack resistance, and the like in a compatible manner. Specifically, a rubber composition comprises: a rubber component; N-cyclohexyl-2-benzothiazolylsulfenamide; a nitrogenous cyclic compound having no benzene ring; a cobalt compound containing no boron; and silica, wherein a content of the nitrogenous cyclic compound is 0.4 parts by mass or less with respect to 100 parts by mass of the rubber component, and a mass ratio (Co/N) of the cobalt content (Co) in the cobalt compound with respect to the nitrogen content (N) in the nitrogenous cyclic compound is in the range of 1.2 to 7.0.

STEEL CORD FOR RUBBER ARTICLE REINFORCEMENT, AND TIRE
20200308763 · 2020-10-01 · ·

Provided is a steel cord for rubber article reinforcement, which has both the tensile strength in the cord axial direction and the strength in the shear direction at higher levels. A steel cord (10) for rubber article reinforcement includes: a single core strand (11) having a layer-twisted structure; and plural sheath strands (12) each having a layer-twisted structure, and the sheath strands (12) are twisted around the core strand (11). In the sheath strands (12), a ratio between the diameter of a core filament (12a) and the diameter of a sheath filament (12b) is 0.75 to 0.85, and a ratio between the strength of the core filament (12a) and the strength of the sheath filament (12b) is 0.55 to 0.7.

Drawing process and wire obtained by drawing process

A steel wire has a microstructure that is completely ferritic, a mixture of ferrite and cementite or a mixture of ferrite and pearlite and has a weight content of carbon C such that C<0.05% and a weight content of chromium Cr such that Cr<12%. The process for drawing the wire comprises: at least one first uninterrupted series of steps of drawing the wire from a diameter D to a diameter d, at least one second uninterrupted series of steps of drawing the wire of diameter d to a diameter d, and one or more intermediate steps between the first and second uninterrupted series of steps of drawing the wire, the wire having a temperature less than or equal to 300 C. during the or each intermediate step.

METALLIC OR METALLIZED REINFORCEMENT, THE SURFACE OF WHICH IS COATED WITH A POLYBENZOXAZINE

Metal or metallized reinforcer, at least the surface of which is at least partially metallic, at least said metallic part being coated with a polybenzoxazine, the repeat units of which comprise at least one unit corresponding to the formulae (I) or (II):

##STR00001##

in which: Z.sub.1 represents an at least divalent, aliphatic, cycloaliphatic or aromatic bonding group comprising at least one carbon atom and optionally at least one heteroatom selected from O, S, N and P; X.sub.1 and X.sub.2, which are identical or different, represent O or S; Ar.sub.1 and Ar.sub.2, which are identical or different, represent a substituted or unsubstituted phenylene group; Z.sub.2 represents O or (S).sub.n, the symbol n representing an integer equal to 1 or greater than 1.

Use of such a reinforcement for the reinforcement of a rubber article, in particular a motor vehicle tyre.

TIRE REINFORCED BY A CARBON STEEL STRIP
20200290401 · 2020-09-17 ·

A motor vehicle tire is reinforced by at least one carbon steel band that has a very low carbon content and high strength in the work-hardened state The carbon steel comprises (% by weight) between 0.05% and 0.4% of carbon, between 0.5% and 4% of manganese, between 0.1% and 2.5% of silicon, optionally (i) less than 1.5% of aluminium, (ii) less than 0.5% of each of the metals boron, chromium, cobalt, copper, molybdenum, nickel, niobium, titanium, tungsten, vanadium, and zirconium, and (iii) less than 0.05% of each of the elements phosphorus, sulfur, nitrogen, or rare earth, and the rest is made up of iron and inevitable impurities resulting from the smelting. The microstructure of the work-hardened carbon steel is mainly martensitic or ferritic-martensitic. The strength, denoted Rm, of the strip is greater than 1200 MPa and its elongation at break, denoted At, is between 1% and 5%.