Abstract:
A pneumatic tire includes metal cords each made of metal filaments twisted together, the metal cords having an initial elongation in a range of from 0.05 to 0.20% and a standard deviation of the initial elongation in a range of not more than 0.02. A method of manufacturing the metal cord comprises shaping metal filaments in a two-dimensional zigzag waveform, and twisting the shaped metal filaments together, wherein the number of the filaments is in a range of from 8 to 12, the metal filaments have the same diameter (d) of from 0.15 to 0.30 mm, the shaped metal filaments have the same zigzag waveforms, the zigzag waveform of each said shaped metal filament has constant wave lengths (P) and constant wave heights (h) wherein the ratio (P/d) is in the range of 100/3 to 700/3, and the ratio (h/d) is in the range of 5/3 to 80/3.
Abstract:
A vehicle wheel tire includes a carcass, a tread, a pair of side walls ending with beads for mounting the tire on a rim, a belt structure, and at least one breaker layer. The belt structure includes first, second, and third belts strips. The first and second belt strips each include metal cords parallel with respect to each other. The first metal cords are crossed with respect to the second metal cords. The third belt strip is in a radially external position with respect to the first and second belt strips. The at least one breaker layer includes reinforcing cords that are inclined with respect to the equatorial plane and is in a radially external position with respect to the belt structure. At least one reinforcing cord of the at least one breaker layer includes at least one metal wire deformed by a substantially sinusoidal deformation lying in a plane.
Abstract:
A tire for a vehicle wheel, includes a torus-shaped carcass, a tread located on a periphery of the carcass, and a pair of axially-facing side walls ending with beads reinforced with bead wires and respective bead-filling elements for mounting the tire on a corresponding rim. The tire includes rubberized fabrics reinforced with metal reinforcing cords. At least one of the metal reinforcing cords comprises at least two wires helicoidally double-twisted around a longitudinal axis of the metal cord. Further, at least one of the wires is permanently deformed by a substantially-sinusoidal deformation lying in a plane.
Abstract:
A heavy duty pneumatic tire has a belt disposed radially outside a carcass and radially inside a tread portion, the belt having at least one ply of at least one high-elongation steel cord, the high elongation steel cord is formed by twisting at least three waving steel filaments together to form a core and a sheath surrounding the core, the waving filaments change place repeatedly along the longitudinal direction of the cord such that one of the filaments forms the core in a portion, but in a different portion of the cord, the same filament forms part of the sheath, thereby defining a plurality of first parts with the core and a plurality of second parts without the core which are disposed alternately in the longitudinal direction of the cord, and the elongation at break of the high-elongation steel cord is in the range of from 4 to 10%, whereby the resistance to breakage of the steel belt cords is improved and it becomes possible to decrease the belt weight without deteriorating various performances.
Abstract:
Device for manufacturing metal cords to be used particularly for reinforcing composite elastomeric products, comprising: a supporting structure (100); a rotor (5) engaged with respect to said supporting structure (100) and rotatable according to a predefined axis; a cradle fastened to said supporting structure (100) according to an oscillation axis which coincides with the rotation axis of the rotor (5); feeding devices operatively fitted on said cradle to feed several elementary wires from the respective feeding spools (8), said elementary wires being driven onto said rotor (5) according to a stranding path with and sections (10A, 10C) coinciding with the rotation axis of the rotor (5) and with a central section (10B) distanced from said rotation axis; at least one preforming device (15) operatively engaged with the cradle and operating on one of said elementary wires in a section upstream with respect to the first end section (10A) of the stranding path. Furthermore, said at least one preforming device (15) is suitable for providing said elementary wire with a substantially sinusoidal deformation without sharp edges.
Abstract:
A metallic cord is composed of metallic filaments gathered together, the metallic filaments include at least one patterned filament which is, before gathered together, two-dimensionally waved so as to have a wave form defined by plural kinds of cycles different from each other in respect of the wave length and/or wave height. A pneumatic tire includes the metallic cords as its carcass cords.
Abstract:
A steel cord is formed by compactly twisting steel filaments together, the steel filaments including a plurality of zigzag filaments and optionally a nonzigzag filament, the zigzag filament being zigzaged two-dimensionally and made up of straight segments each extending between the zigzag peak points, the nonzigzag filament being straight. In case the cord is composed of only the zigzag filaments, the zigzag filaments include at least two kinds of zigzag filaments having different zigzag pitch lengths. In case the cord is composed of both the zigzag filaments and nonzigzag filaments, some of the zigzag and nonzigzag filaments are first loosely twisted together into a bunch, and then a plurality of bunches are twisted together into the cord. In any case, the zigzag pitch length and zigzag wave height of each zigzag filament are substantially constant along the length thereof. A Tire comprises a reinforcing layer such as a tread reinforcing belt layer, carcass, bead reinforcing layer and the like made of the above-mentioned steel cords.
Abstract:
A pneumatic tire comprises a carcass extending between bead portions through a tread portion and sidewall portions, and a belt disposed radially outside of the carcass in the tread portion, wherein the belt comprises at least one monofilament cord ply made of parallel monofilament cords, each monofilament cord is a single metallic filament having a circular cross sectional shape, a diameter of from 0.35 to 0.70 mm, a tensile strength of from 2800 to 3700 Newton/sq.mm, and a bending rigidity of from 35 to 260 gf cm, and the cord count of the monofilament cords in the monofilament cord ply is in a range of from 30 to 50 /5 cm.
Abstract:
A method for using a bunching type twisting machine to manufacture a steel cord made up of one core filament having a continuous wavy form and five to eight sheath filaments not having a wavy form disposed around the core filament, the cross-sectional shape of the cord forming an ellipse whose orientation is substantially constant in the length direction of the cord. After a core filament is preformed with a helical wavy form of a smaller pitch than the cord twisting pitch, this is squashed to form a flat helical core filament at a stage before it is twisted together with sheath filaments, and then sheath filaments are twisted around this flat helical core filament to make an intermediate product cord and this intermediate product cord is then squashed and thereby flattened before being taken up on a reel.
Abstract:
A steel cord for reinforcing rubber articles and a pneumatic radial tire having a belt layer using the same, in which the steel cord comprises a core made of a steel filament wave-shaped in a plane (crimped) and turned (curled) and 5-8 sheath filaments wound around the core in the same direction as the turn direction of the core. The wavelength .lambda.c of the core is preferably defined as 8 dc.ltoreq..lambda.c.ltoreq.30 dc when the diameter of the core filament is dc, and the turn-number nc of the core around the center axis of the core per one wave-length of the core is preferably defined as 0.12.ltoreq.nc.ltoreq.0.85 (turn/pitch).
Abstract translation:一种用于加强橡胶制品的钢丝帘线和具有使用该带束层的带束层的充气子午线轮胎,其中钢帘线包括由在平面(卷曲)中波浪形并且转动(卷曲)的钢丝芯制成的芯线, 8根护套细丝以与芯的转动方向相同的方向缠绕在芯上。 当核心丝的直径为直径时,芯的波长λc优选定义为8 dc = dc dc,并且芯的中心轴的转数nc围绕芯的中心轴 芯的一个波长优选定义为0.12≤nc≤0.85(转/间距)。