Abstract:
Provided are a steel cord for reinforcing rubber whose fatigue resistance is increased more than ever to enable achieving high durability that was not conventionally realized, and a pneumatic radial tire including the steel cord as a reinforcement member.In a steel cord for reinforcing rubber having a double-twist structure that includes a plurality of strands twisted together in the same direction with the same pitch and including a central structure and at least one outer layer, the central structure is composed of at least two strands being twisted around each other and each being composed of at least seven filaments being twisted together. In a steel cord for reinforcing rubber including at least three core strands being twisted together and at least six sheath strands being twisted together around the core strands, the core strands and the sheath strands are twisted in the same direction.
Abstract:
In order that spaces, including a space in the central portion, inside a steel cord used as a reinforcement by being embedded in a tire or the like are filled with an uncured rubber, the uncured rubber is coated on plural steel filaments 115 which are then stranded in case of a single layer steel cord, the uncured rubber is coated on all of plural core filaments 329 which are then stranded along with outer layer filaments 330 in the same direction at the same pitch in case of a 2-layer steel cord of 1 stranding process, and the uncured rubber is coated on all or 2 to 4 core filaments 218 or on at least one of 3 or 4 steel filaments 408, 408null to form a core strand and outer layer filaments 410, 410null are stranded therearound in case of 2-layer steel cord of 2 stranding process. Consequently, it is possible to exhibit satisfactory corrosion resistance and satisfactory fatigue resistance as a steel cord, shorten a curing time in tire component assembling or the like to attain energy saving and prolong the life of a steel cord itself and the life of a tire or the like using the same as a reinforcement. Further, production can be performed at low cost.
Abstract:
A pneumatic tire comprises a tread portion, a pair of sidewall portions, a pair of bead portions, and a carcass ply of steel cords extending between the bead portions through the tread portion and sidewall portions. Each of the carcass cords comprises a number nullnnull of steel filaments each having a diameter (d) of from 0.17 to 0.40 mm. The steel filaments are twisted together to have a null1nullnnull bundle-twist structure or an interlace-twist structure. In a vicinity of the maximum tire section width point P of each of the sidewall portions, a sectional shape coefficient S of each carcass cord is set in a range of from 0.5 to 0.9, wherein the sectional shape coefficient S is (d2nulln)/(L1nullL2), nullnnull is the number of the filaments, nulldnull is the average of the diameters of the filaments, nullL1null is the largest measure of distance between two extremities of the cord which occurs in a direction in a cross section of the cord, and nullL2null is the measure of distance between two extremities of the cord in a direction perpendicular to the above-mentioned direction.
Abstract:
The steel cord has the 1.times.9 structure, in which three core wires and six thicker outer wires are twisted in the same direction with the same pitch, and has a flat shape in the section which is taken perpendicularly to the longitudinal section thereof. The six outer wires having at least two gaps between adjacent ones and the core wires have at least one gap between adjacent ones.
Abstract:
The invention is directed to several embodiments of metallic cord for the reinforcement of tires wherein one or more coaxial layers of metallic filaments are arranged around the metallic core filaments and twisted in the same direction at the same pitch. In one embodiment, the ratio of the diameter of the core filaments to the layer filaments is at least 1.28. In another embodiment, two of the core filaments have a first diameter and the third core filament has a second diameter smaller than the first diameter daimeter. In still another embodiment, two of the core filaments have a first diameter and a third of the core filaments has a second diameter smaller than the first diameter while the coaxial layer filaments have a third diameter equal to the second diameter. In another embodiment, the core has three core filaments twisted about each other and a coaxial layer of eight layer filaments arranged around the core filaments. In yet another embodiment, the core filaments have a first diameter and the layer filaments have a second diameter which is larger than the first diameter.
Abstract:
A steel cord (1) for the reinforcement of rubber articles such as tires includes a core of two to four steel filaments (2) and a layer of steel filaments (3, 4) around the core. All of the filaments have a diameter between 0.15 and 0.40 mm and are twisted in the same direction and at the same pitch. The cord has over a substantial portion of its entire length cross-sections where the accumulated gaps between adjacent layer filaments are at least 0.03 mm. At least one filament of the layer has been preformed differently from the other filaments. The above structure avoids core migration.
Abstract:
A reinforcement assembly to be impregnated with a plastic or rubber material for reinforcing an article, such as a pneumatic tire, the assembly having three layers of cords: a core layer, an intermediate layer and an outer layer. The intermediate layer and the outer layer have the same direction of winding and the same pitch. When the core layer is wound in the same direction as the intermediate layer, the pitches of these layers differ in such a manner that the ratio between the difference in the values of these two pitches and the larger value of these two pitches is at least equal to 0.30. In the intermediate layer the axis of each cord is arranged along a helix such that the ratio between the radius of curvature of said helix and the diameter of said cord is less than 75.
Abstract:
A cable comprises at least one layer of strands (10) with each strand covered with an individual sheath (20) of rubber or plastics material. The sheaths are so shaped (16, 17, 18) that the sheaths of adjacent strands interlock. This provides a layer in which the strands have a generally fixed spatial relationship both to each other and within the cable. This reduces inter-strand forces, so increasing cable life, and also provides a dimensionally stable cable.
Abstract:
A method of constructing a wire rope from plural outer strands and a core, the core having one or more core strands, each of the one or more core strands having plural core wires, the method comprising: swaging the core to laterally compress the core to an extent sufficient to cause concave deformation of at least some of the plural core wires; and closing the plural outer strands over the core to produce the wire rope.
Abstract:
Provided is a rubber-reinforcing steel cord that has superior productivity and is advantageous in reducing weight and improving bending resistance, as well as a conveyor belt that uses the rubber-reinforcing steel cord. A rubber-reinforcing steel cord 1 having a 1+6+(6+6) structure formed by twisting individual steel wires 2, 3, 4a, and 4b once in the same direction, a twist multiple of at least 9 and not greater than 14, and an outer diameter of not greater than 4 mm is used by being embedded in a rubber product.