Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/0007—Reinforcements made of metallic elements, e.g. cords, yarns, filaments or fibres made from metal
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C9/22—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel the plies being arranged with all cords disposed along the circumference of the tyre
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B1/00—Constructional features of ropes or cables
  • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
  • D07B1/0606—Reinforcing cords for rubber or plastic articles
  • D07B1/0646—Reinforcing cords for rubber or plastic articles comprising longitudinally preformed wires
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C2009/0071—Reinforcements or ply arrangement of pneumatic tyres characterised by special physical properties of the reinforcements
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C2009/0071—Reinforcements or ply arrangement of pneumatic tyres characterised by special physical properties of the reinforcements
  • B60C2009/0092—Twist structure
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C2009/2074—Physical properties or dimension of the belt cord
  • B60C2009/2077—Diameters of the cords; Linear density thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C2009/2074—Physical properties or dimension of the belt cord
  • B60C2009/2093—Elongation of the reinforcements at break point
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C2009/2074—Physical properties or dimension of the belt cord
  • B60C2009/2096—Twist structures
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C9/22—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel the plies being arranged with all cords disposed along the circumference of the tyre
  • B60C2009/2252—Physical properties or dimension of the zero degree ply cords
  • B60C2009/2257—Diameters of the cords; Linear density thereof
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C9/22—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel the plies being arranged with all cords disposed along the circumference of the tyre
  • B60C2009/2252—Physical properties or dimension of the zero degree ply cords
  • B60C2009/228—Elongation of the reinforcements at break point
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60C—VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
  • B60C9/00—Reinforcements or ply arrangement of pneumatic tyres
  • B60C9/18—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers
  • B60C9/20—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel
  • B60C9/22—Structure or arrangement of belts or breakers, crown-reinforcing or cushioning layers built-up from rubberised plies each having all cords arranged substantially parallel the plies being arranged with all cords disposed along the circumference of the tyre
  • B60C2009/2252—Physical properties or dimension of the zero degree ply cords
  • B60C2009/2285—Twist structures
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B1/00—Constructional features of ropes or cables
  • D07B1/06—Ropes or cables built-up from metal wires, e.g. of section wires around a hemp core
  • D07B1/0606—Reinforcing cords for rubber or plastic articles
  • D07B1/062—Reinforcing cords for rubber or plastic articles the reinforcing cords being characterised by the strand configuration
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/20—Rope or cable components
  • D07B2201/2015—Strands
  • D07B2201/2022—Strands coreless
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/20—Rope or cable components
  • D07B2201/2015—Strands
  • D07B2201/2024—Strands twisted
  • D07B2201/2029—Open winding
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2201/00—Ropes or cables
  • D07B2201/20—Rope or cable components
  • D07B2201/2015—Strands
  • D07B2201/2038—Strands characterised by the number of wires or filaments
  • D07B2201/2039—Strands characterised by the number of wires or filaments three to eight wires or filaments respectively forming a single layer
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2205/00—Rope or cable materials
  • D07B2205/30—Inorganic materials
  • D07B2205/3021—Metals
  • D07B2205/3025—Steel
  • D07B2205/3046—Steel characterised by the carbon content
  • D07B2205/3053—Steel characterised by the carbon content having a medium carbon content, e.g. greater than 0,5 percent and lower than 0.8 percent respectively HT wires
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2205/00—Rope or cable materials
  • D07B2205/30—Inorganic materials
  • D07B2205/3021—Metals
  • D07B2205/3025—Steel
  • D07B2205/3046—Steel characterised by the carbon content
  • D07B2205/3057—Steel characterised by the carbon content having a high carbon content, e.g. greater than 0,8 percent respectively SHT or UHT wires
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2401/00—Aspects related to the problem to be solved or advantage
  • D07B2401/20—Aspects related to the problem to be solved or advantage related to ropes or cables
  • D07B2401/2005—Elongation or elasticity
  • D07B2401/201—Elongation or elasticity regarding structural elongation
• • D—TEXTILES; PAPER
  • D07—ROPES; CABLES OTHER THAN ELECTRIC
  • D07B—ROPES OR CABLES IN GENERAL
  • D07B2501/00—Application field
  • D07B2501/20—Application field related to ropes or cables
  • D07B2501/2046—Tyre cords

Definitions

• the present invention relates to metal cables used for the reinforcement of articles such as tires for vehicles.
• tire is meant a tire intended to form a cavity by cooperating with a support element, for example a rim, this cavity being able to be pressurized at a pressure higher than atmospheric pressure.
• a tire according to the invention has a substantially toroidal structure.
• Each metallic wire element consists of a steel monofilament and has a diameter equal to 0.38 mm.
• the metallic wire elements define an internal arch of the cable.
• the preform and the inner arch provide the cable, when assembled, with relatively large ventilation, in other words, a space between each pair of adjacent relatively large metallic wire elements.
• Such ventilation generates a structural elongation As of the cable equal to 2.3%.
• Such a cable is in particular intended to be used in tires, for example tires for vehicles of the heavy goods vehicle type.
• this prior art cable has a relatively low longitudinal compressibility, that is to say that the cable buckles under a longitudinal compression deformation relatively small.
• Such buckling results in local bending of the cable, on the one hand, causing the compressive stiffness of the cable to drop and, on the other hand, leading to a risk of damage to the metallic wire elements under the cycling effects which they undergo. for example tires.
• a metallic cable comprising a single layer of metallic wire elements wound in a helix
• the cable 3.26 of WO2016 / 166056 has a relatively low longitudinal compressibility.
• the invention aims to provide cables comprising a single layer of N metallic wire elements wound in a helix and having on the one hand, excellent longitudinal compressibility, and on the other hand, a relatively small diameter compared to the diameters of the metallic wire elements constituting it.
• the invention relates to a cable comprising a single layer of metallic wire elements wound in a helix, each metal wire element of the layer describing, when the cable extends in a substantially rectilinear direction, a helical trajectory around a main axis substantially parallel to the substantially rectilinear direction, so that, in a cutting plane substantially perpendicular to the main axis, the distance between the center of each metallic wire element of the layer and the main axis is equal to half the helix diameter Dh and is substantially constant and equal for all the metallic wire elements of the layer, the metal wire elements defining an internal arch of the cable of diameter Dv, each wire element metallic having a diameter Df and a radius of curvature of a propeller Rf,
• the cable according to the invention has, as the comparative tests described below demonstrate, excellent longitudinal compressibility and, all other things being equal, a relatively small diameter.
• the inventors at the origin of the invention hypothesize that, due to a radius of curvature Rf sufficiently high compared to the diameter Df of each metallic wire element, the cable is sufficiently ventilated, thus reducing the risk of buckling, due to the relatively large distance of each metallic wired element from the longitudinal axis of the cable, a distance allowing the metallic wired elements to accommodate, by their helix, relatively compressive longitudinal deformations high.
• the radius of curvature Rf of each metallic wire element of the prior art cable being relatively small compared to the diameter Df, the metal wire elements are closer to the longitudinal axis of the cable and can accommodate, from by their propeller, longitudinal compression strains much less than the cable according to the invention.
• the cable according to the invention would have a longitudinal stiffness in compression insufficient to ensure a role of reinforcement, for example of tires.
• the cable would have, relative to the diameter of the metallic wire elements, a too large diameter.
• the cable would have too little space between the metallic wire elements for the latter to be able to accommodate relatively high longitudinal compression strains without buckling.
• the values of the characteristics Dh, Df, Dv and Rf as well as of the other characteristics described below are measured on or determined from the cables either directly after manufacture, that is to say before any stage of flooding in an elastomeric matrix, or extracted from an elastomeric matrix, for example from a tire, and then having undergone a cleaning step during which any elastomeric matrix, in particular any material present inside the cable, is removed from the cable.
• the adhesive interface between each metallic wire element and the elastomeric matrix must be removed, for example by electrochemical process in a sodium carbonate bath.
• the effects associated with the shaping step of the tire manufacturing process described below, in particular the elongation of the cables are canceled out by the extraction of the ply and of the cable which, during extraction, resume substantially their characteristics before the conformation stage.
• the cable according to the invention comprises a single layer of metal wire elements wound in a helix.
• the cable according to the invention comprises a single, not two, or more than two layers of metallic wire elements wound in a helix.
• the layer is made up of metallic wire elements, that is to say several metallic wire elements, not of a single metallic wire element.
• the cable according to the invention consists of the layer of wound metallic wire elements, in other words the cable does not comprise any other element wireframe than those of the layer.
• the cable according to the invention is a single helix.
• a single helix cable is a cable in which the axis of each metallic wire element of the layer describes a single helix, unlike a double helix cable in which the axis of each metal wire element describes a first helix around the axis of the cable and a second helix around a propeller described by the axis of the cable.
• the cable when the cable extends in a substantially rectilinear direction, the cable comprises a single layer of metallic wire elements wound together in a helix, each metal wire element of the layer describing a trajectory in the form of an helix around of a main axis substantially parallel to the substantially straight direction so that, in a section plane substantially perpendicular to the main axis, the distance between the center of each metallic wire element of the layer and the main axis is substantially constant and equal for all the metallic wire elements of the layer.
• a double helix cable when a double helix cable extends in a substantially rectilinear direction, the distance between the center of each metallic wire element of the layer and the substantially rectilinear direction is different for all the metallic wire elements of the layer.
• the cable according to the invention has no metallic central core. There is also talk of a 1xN structure cable in which N is the number of metallic wire elements or even an open-structure cable.
• the internal vault is empty and therefore devoid of any filling material, in particular devoid of any elastomeric composition. This is called a cable devoid of filling material.
• the arch of the cable according to the invention is delimited by the metallic wire elements and corresponds to the volume delimited by a theoretical circle, on the one hand, radially inside each metal wire element and, on the other hand, tangent to each metallic wire element.
• the diameter of this theoretical circle is equal to the vault diameter Dv.
• wire element means an element extending longitudinally along a main axis and having a section perpendicular to the main axis whose largest dimension G is relatively small compared to the dimension L along the main axis.
• relatively small it is meant that L / G is greater than or equal to 100, preferably greater than or equal to 1000.
• This definition covers both wire elements of circular section as well as wire elements of non-circular section, for example of polygonal section. or oblong.
• each metallic wire element has a circular section.
• metallic by definition is meant a wire element made up mainly (that is to say for more than 50% of its mass) or entirely (for 100% of its mass) of a metallic material.
• Each metallic wire element is preferably made of steel, more preferably made of perlitic or ferritic-perlitic carbon steel, commonly called by those skilled in the art carbon steel, or else stainless steel (by definition, steel comprising at least 10.5% chrome).
• an elongation force curve includes, moving towards increasing elongations, a structural part, an elastic part and a plastic part.
• the structural part corresponds to the structural elongation As resulting from the ventilation of the cable, that is to say the vacant space between the various metallic wire elements constituting the cable.
• the elastic part corresponds to an elastic elongation resulting from the construction of the cable, in particular the angles of the different layers and the diameters of the wires.
• the plastic part corresponds to the plastic elongation resulting from the plasticity (irreversible deformation beyond the elastic limit) of one or more metallic wire elements.
• the helix diameter Dh corresponds to the diameter of the theoretical circle passing through the centers of the metallic wire elements of the layer in a plane perpendicular to the main axis of the cable.
• the pitch at which each metallic wire element is wound is the length traveled by this wire element, measured parallel to the axis of the cable in which it is located, at the end of which the wire element having this pitch performs one complete turn around said axis of the cable.
• all the metallic wire elements have the same diameter Df.
• the cable is manufactured in accordance with a method and using an installation described in documents WO2016083265 and WO2016083267.
• a method implementing a fractionation step is to be distinguished from a conventional wiring method comprising a single assembly step in which the metallic wire elements are wound in a helix, the assembly step being preceded by a step individual preforming of each wire element in order to increase the value of the structural elongation in particular.
• Such methods and installations are described in documents EP0548539, EP1000194, EP0622489, WO2012055677, JP2007092259, W02007128335, JPH06346386 or even EP0143767.
• the metallic monofilaments are individually preformed.
• this step of individual preforming of the metallic monofilaments which requires a special installation, on the one hand, makes the process relatively unproductive compared to a process without an individual preforming step without however making it possible to achieve structural elongations.
• Such an alteration creates primers for ruptures on the surface of the metallic monofilaments and is therefore harmful for the endurance of the metallic monofilaments, in particular for their endurance in compression.
• the absence or presence of such preform marks can be observed under the electron microscope at the end of the manufacturing process, or much more simply, by knowing the cable manufacturing process.
• each metallic wire element of the cable is devoid of preformation mark.
• preformation marks include in particular flats.
• the preformation marks also include cracks extending in cutting planes substantially perpendicular to the main axis along which extends each metallic wire element. Such cracks extend, in a section plane substantially perpendicular to the main axis, from a radially external surface of each metallic wire element radially towards the inside of each metallic wire element. As described above, such cracks are initiated by the mechanical preforming tools due to the bending forces, that is to say perpendicular to the main axis of each wire element metallic, which makes them very harmful for endurance.
• any range of values designated by the expression “between a and b” represents the range of values ranging from more than a to less than b (that is to say limits a and b excluded) while any range of values designated by the expression “from a to b” signifies the range of values going from a to b (that is to say including the strict limits a and b).
• radial section or radial section here is meant a section or section along a plane which comprises the axis of rotation of the tire.
• axial direction is meant the direction substantially parallel to the axis of rotation of the tire.
• circumferential direction is meant the direction which is substantially perpendicular both to the axial direction and to a radius of the tire (in other words, tangent to a circle whose center is on the axis of rotation of the pneumatic).
• radial direction is meant the direction along a radius of the tire, that is to say any direction intersecting the axis of rotation of the tire and substantially perpendicular to this axis.
• the median plane (denoted M) is the plane perpendicular to the axis of rotation of the tire which is located midway between the two beads and passes through the middle of the crown reinforcement.
• the equatorial circumferential plane (denoted E) of the tire is the theoretical plane passing through the equator of the tire, perpendicular to the median plane and to the radial direction.
• the equator of the tire is, in a circumferential cutting plane (plane perpendicular to the circumferential direction and parallel to the radial and axial directions), the axis parallel to the axis of rotation of the tire and located equidistant between the point radially the outermost of the tread intended to be in contact with the ground and the radially innermost point of the tire intended to be in contact with a support, for example a rim, the distance between these two points being equal to H.
• orientation of an angle is meant the direction, clockwise or counterclockwise, in which it it is necessary to turn from a reference line, here the circumferential direction of the tire, defining the angle to reach the other line defining the angle.
• the helix radius of curvature Rf is such that 2 mm ⁇ Rf ⁇ 7 mm.
• a cable intended for reinforcing a tire for passenger vehicles but also for two-wheeled vehicles such as motorcycles, and preferably for passenger vehicles, there is 2 mm ⁇ Rf ⁇ 5 mm and preferably 3 mm ⁇ Rf ⁇ 5 mm.
• a cable intended for reinforcing a tire for industrial vehicles chosen from vans, "Heavy goods vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), we have 4 mm ⁇ Rf ⁇ 6 mm and preferably 4 mm ⁇ Rf ⁇ 5 mm.
• a cable intended for reinforcing a tire for off-road vehicles for example agricultural or civil engineering machinery, we have 4 mm ⁇ Rf ⁇ 7 mm and preferably 4 , 5 mm ⁇ Rf ⁇ 6.5 mm.
• the helix diameter Dh of each metallic wire element is such that 0.40 mm ⁇ Dh ⁇ 1.50 mm.
• a cable intended for reinforcing a tire for passenger vehicles but also for two-wheeled vehicles such as motorcycles, and preferably for passenger vehicles, there is 0.50 mm ⁇ Dh ⁇ 1.00 mm and preferably 0.70 mm ⁇ Dh ⁇ 1.00 mm.
• a cable intended for reinforcing a tire for industrial vehicles chosen from vans, "Heavy goods vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), we have 0.85 mm ⁇ Dh ⁇ 1.25 mm and preferably 0.90 mm ⁇ Dh ⁇ 1.15 mm.
• a cable intended for reinforcing a tire for off-road vehicles for example agricultural or civil engineering vehicles
• Df is such that 0.10 mm ⁇ Df ⁇ 0.50 mm.
• a cable intended for reinforcing a tire for passenger vehicles but also for two-wheeled vehicles such as motorcycles, and preferably for passenger vehicles, there is 0.20 mm ⁇ Df ⁇ 0.35 mm and preferably 0.25 mm ⁇ Df ⁇ 0.33 mm.
• a cable intended for the reinforcement of a tire for industrial vehicles chosen from vans, "Heavy goods vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), we have 0.22 mm ⁇ Df ⁇ 0.40 mm and preferably 0, 25 mm ⁇ Df ⁇ 0.38 mm.
• a cable intended for reinforcing a tire for off-road vehicles for example agricultural or civil engineering machinery
• Dv is such that Dv> 0.46 mm.
• a cable intended for reinforcing a tire for passenger vehicles but also for two-wheeled vehicles such as motorcycles, and preferably for passenger vehicles, there is 0.46 mm ⁇ Dv ⁇ 0.70 mm.
• a cable intended for reinforcing a tire for industrial vehicles chosen from vans, "Heavy goods vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), we have 0.50 mm ⁇ Dv ⁇ 0.80 mm.
• each metallic wire element is wound at a pitch P such that 3 mm ⁇ P ⁇ 15 mm.
• a cable intended for reinforcing a tire for passenger vehicles but also for two-wheeled vehicles such as motorcycles, and preferably for passenger vehicles, there is 3 mm ⁇ P ⁇ 9 mm.
• the cable has a diameter D such that D ⁇ 2.00 mm.
• the apparent diameter or diameter, denoted D is measured by means of a thickness comparator whose diameter of the keys is at least equal to 1.5 times the pitch P of winding of the wire elements (we can cite for example the model JD50 of the brand KAEFER allowing to reach a precision of 1/100 of a millimeter, equipped with key type a, and having a contact pressure close to 0.6N).
• the measurement protocol consists of three repetitions of a series of three measurements (performed perpendicular to the axis of the cable and at zero voltage), the second and third of these measurements are taken in a direction offset angularly from the previous one. a third of a turn, by rotating the measurement direction around the cable axis.
• a cable intended for reinforcing a tire for passenger vehicles but also for two-wheeled vehicles such as motorcycles, and preferably for passenger vehicles, there is 0.75 mm ⁇ D ⁇ 1.40 mm and preferably 1.00 mm ⁇ D ⁇ 1.30 mm.
• a cable intended for reinforcing a tire for industrial vehicles chosen from vans, "Heavy goods vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), we have 1.15 mm ⁇ D ⁇ 1.55 mm.
• a cable intended for the reinforcement of a tire for off-road vehicles for example agricultural or civil engineering machinery, there are 1.5 mm ⁇ D ⁇ 2 mm.
• each metallic wire element comprises a single metallic monofilament.
• each metallic wire element advantageously consists of a metallic monofilament.
• the metallic monofilament is directly coated with a layer of a metallic coating comprising copper, zinc, tin, cobalt or an alloy of these metals, for example brass or the bronze.
• each metallic wire element then consists of the metallic monofilament, for example of steel, forming a core, directly coated with the layer of metallic coating.
• each metallic elementary monofilament is, as described above, preferably made of steel, and has a mechanical resistance ranging from 1000 MPa to 5000 MPa.
• Such mechanical strengths correspond to the grades of steel commonly encountered in the tire field, namely, the grades NT (Normal Tensile), HT (High Tensile), ST (Super Tensile), SHT (Super High Tensile), UT ( Ultra Tensile), UHT (Ultra High Tensile) and MT (Mega Tensile), the use of high mechanical resistances possibly allowing an improved reinforcement of the matrix in which the cable is intended to be drowned and a reduction in the matrix thus reinforced.
• the layer consisting of N metallic wire elements wound in a helix, N ranges from 3 to 6.
• the ratio K of the pitch P over the diameter Df of each element wireframe, P and Df being expressed in millimeters, is such that 19 ⁇ K ⁇ 44.
• the helix angle a of each metallic wire element is such that 13 ° £ to £ 21 °.
• the cable has a structural elongation As such that As> 1%, preferably As> 2.5%, more preferably As> 3% and even more preferably 3% ⁇ As ⁇ 5.5%, the structural elongation As being determined by applying standard ASTM D2969-04 of 2014 to the cable so as to obtain a force-elongation curve, the structural elongation As being equal to the elongation, in%, corresponding to the maximum slope of the curve force-elongation.
• each metallic wire element is devoid of preformation marks.
• the cable is obtained by a process devoid of individual preforming steps for each of the metallic wire elements.
• the cable according to the invention is manufactured in accordance with a method and using an installation described in documents WO2016083265 and WO2016083267.
• This method comprises a step of assembling by twisting a transient assembly comprising M metallic wire elements during which the M metallic reinforcing elements are preformed collectively and simultaneously on a transient core, then a step of separating the transient assembly between the transient core and the cable according to the invention during which the transient assembly is separated between the transient core and at least part of the M metallic wire elements of the transient assembly to form the cable according to the invention.
• the pitch of each metal wire element of the transient assembly changes from a transient pitch to the pitch P which is greater than it.
• the helix diameter Dh of each metallic wire element in the cable is substantially greater than the transient helix diameter of each wire element in the transient assembly, due to the elastic return.
• the helix diameter Dh of each metallic wire element in the cable is all the more greater than the transient helix diameter of each wire element in the transient assembly as the twisting rate is important.
• the step of fractionating the transient assembly comprises a step of separating the transient core from the first and second assemblies.
• the first assembly consists of M1 metallic wire elements wound together and distributed in a single layer around the axis of the first assembly.
• the second assembly of this embodiment consists of M2 metallic wire elements wound together and distributed in a single layer around the axis of the second assembly.
• the first assembly is separated from a transient assembly formed by the second assembly and the transient core, then the second assembly and the transitory nucleus of each other.
• the transient core, the first assembly and the second assembly are separated in pairs from each other simultaneously.
• the method comprises a step of recycling the transient core during which:
• the step of recycling the transient core can be done continuously, that is to say in which one re-introduces, without step of intermediate storage of the transient core, the transient core leaving the separation stage, in the assembly stage.
• the step of recycling the transient core is discontinuous, that is to say with an intermediate storage step of the transient nucleus.
• transient textile core is used.
• the step of splitting the transient assembly comprises a step of splitting the transient core between at least the first and second assemblies.
• two assemblies of metallic wire elements are obtained, each comprising a layer respectively of P1, P2 metallic wire elements wound together in a helix, and for at least one of the assemblies, a central core comprising or constituted by 'at least part of the transient core around which the metallic wire elements of the layer are wound.
• the transient core comprising K metallic wire element (s), at least one of the K metallic wire element (s) of the transient core belongs to at least one of the first and second assemblies of M1 metallic wire elements and M2 metallic wire elements.
• At least a first part of the transient core is fractionated with first metallic wire elements of the transient assembly so as to form the first assembly.
• the first assembly comprises a layer of P1 metallic wire elements wound together in a helix and a central core comprising or constituted by a first part (K1 wire element (s)) of the K metal wire elements of the transient core and around which the P1 metallic wire elements are wound together in a helix.
• K1 wire element (s) a first part of the K metal wire elements of the transient core and around which the P1 metallic wire elements are wound together in a helix.
• At least a second part of the transient core is fractionated with second metallic wire elements of the transient assembly so as to form the second assembly.
• the second assembly comprises a layer of P2 metallic wire elements wound together in a helix and a central core comprising or constituted by a second part (K2 wire element (s)) of the K wire elements of the transient core and around which the P2 metallic wire elements are wound together in a helix.
• K2 wire element (s) K2 wire element
• the first and second assemblies are formed simultaneously.
• the first and second parts of the transient core constitute the transient core.
• the assembly step is carried out by twisting.
• the metallic wire elements undergo both a collective twist and an individual twist around their own axis, which generates a twist torque on each of the metal wire elements.
• the assembly step is carried out by wiring. In this case, the metallic wire elements do not undergo torsion around their own axis, due to a synchronous rotation before and after the assembly point.
• the method comprises a step of balancing the transient assembly.
• the balancing step being carried out on the assembly consisting of M metallic wire elements and the transient core, the balancing step is implicitly carried out upstream of the fractionation step.
• the method comprises a balancing step of at least one of the first and second assemblies after the fractionation step.
• the method comprises a step of maintaining the rotation of the first and second assemblies around their respective direction of travel. This step is carried out after the fractionation step and before the balancing step of at least one of the first and second assemblies.
• the invention also relates to the use of such a cable for the reinforcement of articles or semi-finished products comprising an elastomeric matrix in which the cable is embedded.
• Such articles or semi-finished products are pipes, belts, conveyor belts, tracks, tires for vehicles, both in the raw state (that is to say before crosslinking or vulcanization) that 'in the cooked state (after crosslinking or vulcanization).
• Such semi-finished articles or products take, in preferred modes, the form of a sheet.
• the invention also relates to an article or semi-finished product comprising an elastomeric matrix in which is embedded at least one cable as defined above.
• Another object of the invention is the use of a cable as defined above for the reinforcement of a tire comprising the cable.
• tire comprising a wired reinforcing element obtained by flooding a cable as defined above in a matrix elastomeric.
• tire is meant a tire intended to form a cavity by cooperating with a support element, for example a rim, this cavity being able to be pressurized at a pressure higher than atmospheric pressure.
• a tire according to the invention has a substantially toroidal structure.
• the cable is embedded in the elastomeric matrix.
• the cable comprises a material for filling the internal arch based on an elastomeric composition and located in the internal arch of the filled cable.
• the filling material is here based on the same elastomeric composition as that based on the elastomeric matrix in which the cable is embedded.
• elastomeric matrix a matrix with elastomeric behavior resulting from the crosslinking of an elastomeric composition.
• the elastomeric matrix is thus based on the elastomeric composition.
• the filling material is based on an elastomeric composition, here the same composition as that of the matrix in which the cable is embedded.
• composition comprises the mixture and / or the in situ reaction product of the different constituents used, some of these constituents being able to react and / or being intended to react between them, at least partially, during the various stages of manufacturing the composition; the composition thus being able to be in the fully or partially crosslinked state or in the non-crosslinked state.
• elastomeric composition comprises at least one elastomer and at least one other component.
• the composition comprising at least one elastomer and at least one other component comprises an elastomer, a crosslinking system and a filler.
• the compositions used for these plies are conventional compositions for calendering reinforcing wire elements, comprise a diene elastomer, for example natural rubber, a reinforcing filler, for example carbon black and / or silica, a system of crosslinking, for example a vulcanization system, preferably comprising sulfur, stearic acid and zinc oxide, and optionally a vulcanization accelerator and / or retarder and / or various additives.
• the adhesion between the reinforcing wire elements and the matrix in which they are embedded is ensured for example by a usual adhesive composition, for example an adhesive of the RFL type or equivalent adhesive.
• the secant modulus in tension of a sheet for a force equal to 15% of the breaking force is denoted MA 15 is expressed in daN / mm.
• the MA 15 module is calculated from a force-elongation curve obtained by applying standard ASTM D2969-04 of 2014 to a cable of the sheet. One calculates the secant module in traction of the cable by determining the slope of the straight line drawn between the points (0,0) and the point of the curve having an ordinate equal to 15% of the breaking force.
• the module MA 15 is determined by multiplying the secant module in cable traction by the cable density per mm of ply.
• the density d of wired reinforcing elements in a sheet is the number of wired reinforcing elements present in the sheet in a direction perpendicular to the direction in which the wired reinforcing elements extend in the sheet.
• the density d can also be determined from the laying pitch p expressed in mm, the laying pitch being equal to the axis-to-axis distance between two consecutive reinforcing wire elements in the direction perpendicular to the direction in which the reinforcing elements extend into the tablecloth.
• the breaking strength of a cable is measured according to standard ASTM D2969-04 of 2014.
• the breaking strength of a ply is calculated from a force-elongation curve obtained by applying standard ASTM D2969- 04 of 2014 to a ribbon cable.
• the breaking strength of the ply is determined by multiplying the breaking strength of the cable by the density of cables per unit width of the ply, this density being as defined above.
• the tires of the invention may be intended for passenger motor vehicles (comprising in particular 4x4 vehicles and "SUVs" (Sport Utility Vehicles)), but also for two-wheeled vehicles such as motorcycles, or to industrial vehicles chosen from vans, "Heavy vehicles” - ie, metro, bus, road transport equipment (trucks, tractors, trailers), off-road vehicles -, agricultural or civil engineering vehicles, aircraft, others transport or handling vehicles.
• passenger motor vehicles comprising in particular 4x4 vehicles and "SUVs" (Sport Utility Vehicles)
• two-wheeled vehicles such as motorcycles
• industrial vehicles chosen from vans, "Heavy vehicles” - ie, metro, bus, road transport equipment (trucks, tractors, trailers), off-road vehicles -, agricultural or civil engineering vehicles, aircraft, others transport or handling vehicles.
• the tires of the invention are intended for passenger vehicles.
• the tire comprises a crown comprising a tread and a crown reinforcement, two sidewalls, two beads, each sidewall connecting each bead to the top, the crown frame extending in the crown. in a circumferential direction of the tire, the tire comprising a carcass reinforcement anchored in each of the beads and extending in the sidewalls and in the crown, the crown reinforcement being radially interposed between the carcass reinforcement and the tread , the crown reinforcement comprising a reinforcing wire element obtained by flooding a cable as defined above in an elastomeric matrix.
• the crown reinforcement comprises a hooping reinforcement comprising at least one hooping ply and preferably a single hooping ply.
• the hooping frame preferably consists of a hooping ply.
• This embodiment is particularly suitable for a tire for passenger vehicles, two-wheeled vehicles, industrial vehicles chosen from vans, "Heavy vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), and preferably for passenger vehicles.
• the crown reinforcement comprises a working reinforcement comprising at least one working ply.
• the hooping reinforcement is radially interposed between the working reinforcement and the tread.
• the hooping reinforcement exercises, in addition to its hooping function, a protective function against punctures and shocks much more effective than a hooping armature comprising wire elements of textile hoop reinforcement.
• the hooping ply comprises at least one wired hoop reinforcement element obtained by embedding a cable as defined above in an elastomeric matrix.
• the cable makes it possible to reduce the thicknesses of the hooping ply, the mass thereof, the hysteresis of the tire and therefore the rolling resistance of the tire.
• the total thickness of the ply is reduced while maintaining the thickness present on the back of each cable which allows the decoupling thicknesses to be maintained between, on the one hand, the tread and the ply of hooping, and on the other hand, the plies radially internal to the hooping ply and the hooping ply.
• the cable makes it possible to give the tire excellent endurance in compression, and this all the more advantageously in the case of the elimination of a working ply compared to a tire of the state of the art described in US2007006957.
• the hooping reinforcement is, due to the use of metallic wired elements, cheaper, more stable thermally and gives mechanical protection to the tire.
• the use of metallic wire elements makes it possible to facilitate the control of the hooping reinforcement by radiography after its manufacture.
• the cable of the tire according to the invention has excellent longitudinal compressibility and therefore a much higher compression endurance.
• the hooping reinforcement exerts, in addition to its hooping function, a protective function against punctures and impacts much more effective than a hooping reinforcement comprising wired textile hoop reinforcement elements.
• the or each wired hooping reinforcing element makes an angle strictly less than 10 °, preferably less than or equal to 7 °, and more preferably less than or equal to 5 ° with the circumferential direction of the tire.
• each working ply comprises several wired working reinforcing elements.
• each wired working reinforcement element is a metallic wired element.
• each wired working reinforcing elements of each ply are arranged side by side substantially parallel to each other. More preferably, each wire work reinforcement element extends axially from one axial end of the working frame of the tire to the other axial end of the working frame of the tire.
• the carcass reinforcement comprises at least one carcass ply and more preferably a single carcass ply.
• the carcass reinforcement is preferably constituted by a carcass ply.
• This embodiment is particularly suitable for a tire for passenger vehicles, two-wheeled vehicles, industrial vehicles chosen from vans, "Heavy vehicles", for example metro, bus, road transport equipment (trucks, tractors, trailers), and preferably for passenger vehicles.
• the carcass ply comprises wired carcass reinforcement elements.
• each wire element of the carcass reinforcement is a wire element textile.
• textile is understood to mean, by definition, a non-metallic filamentary element consisting of one or more elementary textile monofilaments optionally coated with one or more layers of a coating based on an adhesive composition.
• Each elementary textile monofilament is obtained, for example, by melt spinning, solution spinning or gel spinning.
• Each elementary textile monofilament is produced from an organic, in particular polymeric, or inorganic material, such as for example glass or carbon.
• the polymeric materials can be of the thermoplastic type, such as, for example, aliphatic polyamides, in particular polyamides 6-6, and polyesters, in particular polyethylene terephthalate.
• the polymeric materials can be of the non-thermoplastic type, such as for example aromatic polyamides, in particular aramid, and cellulose, natural as well as artificial, in particular rayon.
• each wired carcass reinforcement element extends axially from one bead of the tire to the other bead of the tire.
• At least the wired working reinforcement elements and the wired carcass reinforcement elements are arranged so as to define, in projection on an equatorial circumferential plane in the radial direction of the tire, a triangular mesh.
• the crown reinforcement consists of the working reinforcement and the hooping reinforcement.
• the term “ply” means the assembly, on the one hand, of one or more wired reinforcing elements and, on the other hand, of an elastomeric matrix, the wired reinforcing element or elements being embedded in the elastomeric matrix.
• the wired reinforcing elements of each ply are embedded in an elastomeric matrix.
• the different layers may comprise the same elastomeric matrix or else separate elastomeric matrices.
• the working frame comprises two working plies and preferably the working frame consists of two working plies.
• the wired working reinforcing elements and the wired carcass reinforcing elements are arranged so as to define, in projection on an equatorial circumferential plane in the radial direction of the tire, a triangular mesh.
• the wired hoop reinforcement elements are not necessary to define the triangular mesh.
• each wired working reinforcement element of each working ply forms an angle ranging from 10 ° to 40 °, preferably from 20 ° to 30 ° with the circumferential direction of the tire.
• the orientation of the angle made by the wired working reinforcement elements with the circumferential direction of the tire in a working ply is opposite to the orientation of the angle made by the wired reinforcing elements of work with the circumferential direction of the tire in the other working ply.
• the wired working reinforcing elements of one working ply are crossed with the wired working reinforcing elements of the other working ply.
• each wired carcass reinforcement element makes an angle greater than or equal to 80 °, preferably ranging from 80 ° to 90 ° with the circumferential direction of the tire in the median plane of the tire, in other words in the top of the tire. pneumatic.
• each wired carcass reinforcement element makes an angle greater than or equal to 80 °, preferably ranging from 80 ° to 90 ° with the circumferential direction of the tire in the equatorial circumferential plane of the tire, in other words in each sidewall. .
• the working frame comprises a single working ply.
• the working frame is preferably constituted by a working ply.
• This embodiment is particularly advantageous when the or each wired hoop reinforcing element is constituted by cable as defined above.
• the mechanical strength and endurance properties of the hooping frame previously described then make it possible to remove a working ply from the working frame. A significantly lighter tire is obtained.
• the wired hoop reinforcement element or elements, the wired work reinforcement elements and the wired carcass reinforcement elements are arranged so as to define, in projection on an equatorial circumferential plane according to the radial direction of the tire, a triangular mesh.
• the wired hoop reinforcement elements are necessary to define the triangular mesh.
• each wired carcass reinforcement element makes an angle A Ci greater than or equal to 55 °, preferably ranging from 55 ° to 80 ° and more preferably ranging from 60 ° to 70 °, with the circumferential direction of the tire. in the median plane of the tire, in other words in the top of the tire.
• the wired carcass reinforcement elements from the angle formed with the circumferential direction, participates in the formation of the triangular mesh in the top of the tire.
• each wired carcass reinforcement element makes an angle A C2 greater than or equal to 85 ° with the circumferential direction of the tire in the equatorial circumferential plane of the tire, in other words in each sidewall of the tire.
• the carcass reinforcing wire elements are substantially radial in each sidewall, that is to say substantially perpendicular to the circumferential direction, which makes it possible to retain all the advantages of a tire with a radial carcass.
• each wired working reinforcement element makes an angle A T greater than or equal to 10 °, preferably ranging from 30 ° to 50 ° and more preferably from 35 ° to 45 ° with the circumferential direction of the tire in the median plane of the tire.
• the wired working reinforcement elements from the angle formed with the circumferential direction, participate in the formation of the triangular mesh in the top of the tire.
• the orientation of the angle A T and the orientation of the angle A Ci are preferably opposite with respect to the circumferential direction of the tire.
• the hoop ply advantageously has a secant module in tension greater than or equal to 300 daN.mm 1 , preferably greater than or equal to 350 daN.mm 1 and more preferably greater than or equal to 400 daN.mm 1 for a force equal to 15% of the breaking force of the hooping ply.
• the hooping ply advantageously has a secant module in tension less than or equal to 500 daN.mm 1 , preferably less than or equal to 450 daN.mm 1 for a force equal to 15% of the breaking force of the hooping ply.
• the breaking force of the hooping ply is greater than or equal to 55 daN.mm 1 , preferably greater than or equal to 60 daN .mm 1 and more preferably greater than or equal to 65 daN.mm 1 .
• the breaking force of the hooping ply is less than or equal to 85 daN.mm 1 , preferably less than or equal to 80 daN.mm 1 and more preferably less than or equal to 75 daN.mm 1 .
• the tire according to the invention is manufactured according to the method described below.
• each carcass ply, each working ply and each hooping ply is manufactured.
• Each ply is manufactured by embedding the reinforcing wire elements of each ply in a non-crosslinked elastomeric composition. Then, the carcass reinforcement, the working reinforcement, the hooping reinforcement and the tread are arranged so as to form a tire blank.
• the tire blank is conformed so as to at least radially enlarge the tire blank.
• This step has the effect of circumferentially lengthening each ply of the tire blank.
• This step has the effect of lengthening the or each wired hoop reinforcement element in the circumferential direction of the tire.
• the or each wired hoop reinforcing element has, before the shaping step, characteristics different from those after the shaping step.
• the characteristics of the cable devoid of filling material described above ensure that, at the end of the tire manufacturing process, taking into account the shaping step, the tire will have the advantages described above.
• compositions of the shaped tire blank are crosslinked, for example by curing or vulcanization, in order to obtain the tire in which each composition has a crosslinked state and forms an elastomeric matrix based on the composition.
• Figure 1 is a radial sectional view of a tire according to a first embodiment of the invention
• FIG. 2 is a cutaway view of the tire of FIG. 1 illustrating the projection onto the equatorial circumferential plane E of the wired hoop reinforcement elements, of the wired work reinforcement elements and of the wired carcass reinforcement elements;
• FIG. 3 is a view of the wired carcass reinforcement elements arranged in the sidewall of the tire of FIG. 1 in projection on the median plane M of the tire;
• Figure 4 is a sectional view perpendicular to its axis of a cable according to a first embodiment of the invention (assumed to be straight and at rest);
• Figure 5 is a perspective view of the cable of Figure 4.
• Figure 6 illustrates a force-elongation curve of the cable of Figures 4 and 5;
• FIG. 7 illustrates a curve representing the variation of the derivative of the curve of FIG. 6 as a function of the elongation
• Figures 8 and 9 are figures similar to Figures 4 and 5 of a cable according to a second embodiment
• Figure 10 is a view similar to that of Figure 1 of a tire according to a second embodiment of the invention.
• Figures 1 1 and 12 are views similar to those of views of Figures 2 and 3 of the tire of Figure 10 according to the second embodiment of the invention.
• FIG. 1 a reference X, Y, Z has been shown corresponding to the usual directions of axial (X), radial (Y) and circumferential (Z) of a tire, respectively.
• Figure 1 a radial sectional view of a tire according to the invention and designated by the general reference 10.
• the tire 10 is substantially of revolution around an axis substantially parallel to the axial direction X.
• the tire 10 is here intended for a passenger vehicle.
• the tire 10 comprises a crown 12 comprising a crown reinforcement 14 comprising a working reinforcement 15 comprising two working plies 16, 18 respectively comprising wired working reinforcement elements 46, 47 and a hooping reinforcement 17 comprising a hoop ply 19 comprising at least one wired hoop reinforcement element 48.
• the crown reinforcement 14 extends in the crown 12 in the circumferential direction Z of the tire 10.
• the crown 12 comprises a tread 20 arranged radially outside to the crown reinforcement 14.
• the hooping reinforcement 17, here the hooping ply 19 is radially interposed between the working reinforcement 15 and the tread 20.
• the working reinforcement 15 comprises only two working plies 16, 18 and the hooping reinforcement 17 comprising a single hooping ply 19.
• the working reinforcement 15 consists of two working plies 16, 18 and l 17 hooping reinforcement is formed of the hooping ply 19.
• the crown reinforcement 14 is formed by the working reinforcement 15 and the hooping reinforcement 17.
• the tire 10 also includes two sidewalls 22 extending the crown 12 radially inward.
• the tire 10 also comprises two beads 24 radially inside the sidewalls 22 and each comprising an annular reinforcement structure 26, in this case a bead wire 28, surmounted by a mass of rubber 30 for bead stuffing, as well as a frame radial carcass 32.
• Each side 22 connects each bead 24 at the top 12.
• the carcass reinforcement 32 comprises a carcass ply 34 comprising several wired carcass reinforcement elements 44, the carcass ply 34 being anchored to each of the beads 24 by an inversion around the rod 28, so as to form in each bead 24 a go strand 38 extending from the beads through the flanks towards the apex 12, and a return strand 40, the radially outer end 42 of the return strand 40 being radially outside the annular structure of reinforcement 26.
• the carcass reinforcement 32 thus extends from the beads 24 in and through the sidewalls 22 as far as the crown 12.
• the carcass reinforcement 32 is arranged radially inside the crown reinforcement 14 and the hooping reinforcement 17.
• the crown reinforcement 14 is therefore radially interposed between the carcass reinforcement 32 and the tread 20.
• the carcass reinforcement 32 comprises a single ply carcass 34.
• the carcass reinforcement 32 consists of the carcass ply 34.
• the tire 10 also includes an internal sealing layer 46, preferably made of butyl, located axially inside the sidewalls 22 and radially inside the crown reinforcement 14 and extending between the two beads 24.
• an internal sealing layer 46 preferably made of butyl, located axially inside the sidewalls 22 and radially inside the crown reinforcement 14 and extending between the two beads 24.
• Each working ply 16, 18, hoop 19 and carcass 34 comprises an elastomeric matrix in which are embedded reinforcing elements of the corresponding ply.
• Each elastomeric matrix of the working plies 16, 18, of hooping 19 and of carcass 34 is based on a conventional elastomeric composition for calendering reinforcing elements conventionally comprising a diene elastomer, for example natural rubber, a filler reinforcing, for example carbon black and / or silica, a crosslinking system, for example a vulcanization system, preferably comprising sulfur, stearic acid and zinc oxide, and optionally an accelerator and / or vulcanization retarder and / or various additives.
• each wired carcass reinforcement element 44 extends axially from a bead 24 of the tire 10 to the other bead 24 of the tire 10.
• Each wired carcass reinforcement element 44 makes an angle A c greater than or equal to 80 °, preferably ranging from 80 ° to 90 °, with the circumferential direction Z of the tire 10 in the median planes M and equatorial circumferential E of the tire 10, in other words in the apex 12 and in each side 22.
• each working ply 16, 18 are arranged side by side substantially parallel to the to each other.
• Each work reinforcement wire element 46, 47 extends axially from one axial end of the work armature 15 of the tire 10 to the other axial end of the work armature 15 of the tire 10.
• Each wire element of working reinforcement 46, 48 makes an angle ranging from 10 ° and 40 °, preferably ranging from 20 ° to 30 ° and here equal to 26 ° with the circumferential direction Z of the tire 10 in the median plane M.
• the orientation of the angle S made by the wired working reinforcement elements 46 with the circumferential direction Z of the tire 10 in the working ply 16 is opposite to the orientation of the angle Q made by the wired working reinforcing elements 47 with the circumferential direction Z of the tire 10 in the other working ply 18.
• the wired working reinforcement elements 46 of working ply 16 are crossed with the wired working reinforcing elements 47 on the other tra tablecloth vail 18 ..
• the single hooping ply 19 comprises at least the wired hooping reinforcement element 48 obtained by embedding the cable 50 in an elastomeric matrix based on the elastomeric composition of the hooping ply 19 and as illustrated in Figures 4 and 5 and described in more detail below.
• the cable 50 Being embedded in the matrix of the hoop ply 19, the cable 50, within the tire 10, comprises a material for filling the inner arch 58 based on the elastomeric composition of the hoop ply 19, this filling material 53 being located in the internal vault 58 of the cable 50.
• the hooping ply 19 comprises a single wired hoop reinforcement element 48 wound continuously over an axial width L F of the crown 12 of the tire 10.
• the width axial L F is less than the width L T of the working ply 18.
• the wired hoop reinforcement element 48 makes an angle A F strictly less than 10 ° with the circumferential direction Z of the tire 10, preferably less than or equal at 7 °, and more preferably less than or equal to 5 °. In this case, the angle is here equal to 5 °.
• the wired carcass reinforcement 44 and working elements 46, 47 are arranged in the apex 12 so as to define, in projection on the equatorial circumferential plane E in the radial direction of the tire, a triangular mesh.
• Each wired carcass reinforcement element 44 is a textile wired element and conventionally comprises two multifilament strands, each multifilament strand consisting of a yarn of polyester monofilaments, here of PET, these two multifilament strands being individually twisted at 240 towers. m 1 in one direction then twisted together at 240 turns. m 1 in the opposite direction. These two multifilament strands are wound in a helix around one another. Each of these multifilament strands has a titer equal to 220 tex.
• Each wired working reinforcement element 46, 47 is a metallic wired element and here is an assembly of two steel monofilaments each having a diameter equal to 0.30 mm, the two steel monofilaments being wound with each other at a pitch of 14 mm.
• the cable 50 comprises a single layer 52 of metallic wire elements 54 wound in a helix.
• the cable 50 consists of the single layer 52, in other words the cable 50 does not comprise any other metallic wire element than those of the layer 52.
• the cable 50 has a main axis A extending substantially parallel to the direction in which the cable extends along its greatest length.
• Each metallic wire element 54 of the layer 52 describes, when the cable 50, extends in a substantially rectilinear direction, a helical trajectory around the main axis A substantially parallel to the substantially rectilinear direction, so that , in a section plane substantially perpendicular to the main axis A, the distance between the center of each metallic wire element 54 of the layer 52 and the main axis A is substantially constant and equal for all the metal wire elements 54 of the layer 52.
• This constant distance between the center of each metallic wire element 54 of layer 52 and the main axis A is equal to half of the helix diameter Dh.
• each metal wire element 54 comprises a single metal monofilament 56.
• Each metal wire element 54 also comprises a layer (not shown) of a metal coating comprising copper, zinc, tin, cobalt or an alloy of these metals, here brass.
• Each metallic monofilament 56 is made of carbon steel and has a mechanical breaking strength here equal to 3100 MPa.
• each metallic wire element 54 is such that 0.10 mm ⁇ Df ⁇ 0.50 mm, preferably 0.20 mm ⁇ Df ⁇ 0.35 mm and more preferably 0.25 mm ⁇ Df
• Each metal wire element 54 is devoid of preformation marks.
• the cable 50 has a diameter D such that D ⁇ 2.00 mm, preferably 0.75 mm
• the cable 50 according to the first embodiment has a structural elongation As such as As> 1%, preferably such as As> 1%, preferably As> 2.5%, more preferably As> 3% and again more preferably 3% ⁇ As ⁇ 5.5% and here equal to 4.8%.
• the value As is determined by drawing a force-elongation curve of the cable by applying standard ASTM D2969-04 of 2014. The curve obtained is shown in FIG. 6. Then, from this elongation force curve, we deduce the variation of the derivative of this elongation force curve.
• FIG. 7 shows the variation of this derivative as a function of the elongation. The highest derivative point then corresponds to the value As.
• the helix angle a of each metallic wire element is such that 13 ° ⁇ a ⁇ 21 °.
• a (1) 20.05 °
• a (2) 20.36 °
• Each metallic wire element 54 has a radius of curvature of a helix Rf such that 2 mm ⁇ Rf ⁇ 7 mm, preferably 2 mm ⁇ Rf ⁇ 5 mm and more preferably 3 mm
• the helix diameter Dh of each metallic wire element is such that 0.40 mm ⁇ Dh ⁇ 1.50 mm, preferably 0.50 mm ⁇ Dh ⁇ 1.00 mm and more preferably 0.70 mm ⁇ Dh ⁇ 1.00 mm.
• the metallic wire elements 54 define an internal arch 58 of the cable 50 of diameter Dv.
• Dv is such that Dv> 0.46 mm and preferably 0.46 mm ⁇ Dv ⁇ 0.70 mm.
• the cable 50 comprises a single layer 52 of metallic wire elements 54 wound in a helix.
• each metal wire element 54 comprises a single metal monofilament 56.
• Each metal wire element 54 also comprises a layer (not shown) of a metal coating comprising copper, zinc, tin, cobalt or an alloy of these metals, here brass.
• each metallic wire element 54 is such that 0.10 mm ⁇ Df ⁇ 0.50 mm, preferably 0.20 mm ⁇ Df ⁇ 0.35 mm and more preferably 0.25 mm ⁇ Df
• Each metal wire element 54 is devoid of preformation marks.
• the cable 50 ’ has a diameter D such that D ⁇ 2.00 mm, preferably 0.75 mm
• the cable 50 Due to the high number of metallic wire elements of the cable 50 ’and its relatively small diameter, the cable 50’ has a relatively moderate structural elongation As here equal to 1.6%.
• the helix angle a of each metallic wire element is such that 13 ° ⁇ a ⁇ 21 °.
• aa (1) 17.35 °
• a (2) 17.87 °
• Each metallic wire element 54 has a radius of curvature of a helix Rf such that 2 mm ⁇ Cf ⁇ 7 mm, preferably 2 mm ⁇ Rf ⁇ 5 mm and more preferably 3 mm
• the helix diameter Dh of each metallic wire element is such that 0.40 mm ⁇ Dh ⁇ 1.50 mm, preferably 0.50 mm ⁇ Dh ⁇ 0.90 mm and more preferably 0.70 mm ⁇ Dh ⁇ 0.90 mm.
• the arch diameter Dv is calculated as in the first embodiment.
• Dv is such that Dv> 0.46 mm and preferably 0.46 mm ⁇ Dv ⁇ 0.60 mm.
• the tire 10 is manufactured according to the method described below.
• the working ply 18 and the carcass ply 34 by arranging parallel to each other the wired reinforcing elements of each ply and by drowning them, for example by calendering, in a composition not crosslinked comprising at least one elastomer, the composition being intended to form an elastomeric matrix once crosslinked.
• a so-called straight ply is obtained, in which the wired reinforcing elements of the ply are parallel to each other and are parallel to the main direction of the ply.
• portions of each straight ply are cut at a cutting angle and these portions are butted together so as to obtain a so-called angled ply, in which the wired reinforcing elements of the ply are parallel to each other and form an angle with the main direction of the web equal to the cutting angle.
• a strip of width B significantly less than L F is manufactured , in which the wired hooping reinforcing element 48 formed by a cable 50 is embedded in the elastomeric matrix based on the non-crosslinked elastomeric composition of the strip and the strip is wound helically over several turns so as to obtain the axial width L F.
• the hooping ply 19 is made having a width l_ F in a similar manner to the carcass and working plies and the hooping ply 19 is wound on a lathe on the working frame 15.
• the wired hooping reinforcement element 48 formed by the cable 50 is wound radially outside the working ply 18, then a layer based on the non-crosslinked elastomeric composition of the hooping ply is deposited thereon 19 and in which the wired hooping reinforcement element 48 formed by the cable 50 will be embedded during the curing of the tire.
• the bonded reinforcing wire element 48 formed by the cable 50 is drowned in a composition to form, at the end of the tire manufacturing process, the hooping ply 19 comprising the wire reinforcing element hooping 48 formed by the cable 50.
• the carcass reinforcement, the working reinforcement, the reinforcement of hooping and the tread so as to form a tire blank in which the compositions of the elastomeric dies are not yet crosslinked and are in a raw state.
• the tire blank is conformed so as to at least radially enlarge the tire blank.
• the compositions of the shaped tire blank are crosslinked, for example by curing or vulcanization, in order to obtain the tire in which each composition has a crosslinked state and forms an elastomeric matrix based on the composition.
• FIGS. 10 to 12 show a tire 10 ’according to a second embodiment of the invention.
• elements similar to those of the tire 10 according to the first embodiment are designated by identical references.
• the tire 10 ′ is substantially of revolution around an axis substantially parallel to the axial direction X.
• the tire 10 ′ is here intended for a passenger vehicle.
• the tire 10 ′ has a crown 12 comprising a tread 20 and a crown reinforcement 14 extending in the crown 12 in the circumferential direction Z.
• the crown reinforcement 14 comprises a working reinforcement 15 comprising a single working ply 18 and a hooping reinforcement 17 comprising a single hooping ply 19.
• the working reinforcement 15 consists of the ply of work 18 and the hooping reinforcement 17 consists of the hooping ply 19.
• the crown reinforcement 14 is constituted by the working reinforcement 15 and the hooping reinforcement 17.
• the crown reinforcement 14 is surmounted by the tread 20.
• the hooping reinforcement 17, here the hooping ply 19, is radially interposed between the working reinforcement 15 and the tread 20 .
• the tire 10 ′ comprises two sidewalls 22 extending the crown 12 radially inwards.
• the tire 10 ′ further comprises two beads 24 radially internal to the sidewalls 22 and each comprising an annular reinforcing structure 26, in this case a bead wire 28, surmounted by a mass of stuffing rubber 30, as well as a reinforcement of radial carcass 32.
• the crown reinforcement 14 is located radially between the carcass reinforcement 32 and the tread 20.
• Each flank 22 connects each bead 24 to the crown 12.
• the carcass reinforcement 32 comprises a single carcass ply 34.
• the carcass reinforcement 32 is made up of carcass ply 34.
• the carcass reinforcement 32 is anchored in each of the beads 24 by an inversion around the rod 28 so as to form in each bead 24 a going strand 38 extending from the beads 24 in the sides 22 and in the crown 12, and a return strand 40, the radially outer end 42 of the return strand 40 being radially outside the annular reinforcing structure 26.
• the carcass reinforcement 32 thus extends from the beads 24 through the flanks 22 as far as the apex 12.
• the carcass reinforcement 32 also extends axially through the crown 12.
• the crown reinforcement 14 is radially interposed between the carcass reinforcement 32 and the tread 20.
• Each working ply 18, hoop 19 and carcass 34 comprises an elastomeric matrix in which are embedded one or more reinforcing elements of the corresponding ply.
• the single carcass ply 34 comprises wired carcass reinforcement elements 44.
• Each wired carcass reinforcement element 44 extends axially from a bead 24 of the tire 10 to the another bead 24 of the tire 10.
• Each wired carcass reinforcement element 44 has an angle A Ci greater than or equal to 55 °, preferably ranging from 55 ° to 80 ° and more preferably from 60 ° to 70 °, with the circumferential direction Z of the tire 10 in the median plane M of the tire 10 ′, in other words in the crown 12.
• each wired carcass reinforcement element 44 makes an angle A C2 greater than or equal to 85 ° with the circumferential direction Z of the tire 10 'in the equatorial circumferential plane E of the pin umatic 10 ′, in other words in each flank 22.
• the single work ply 18 comprises several wired working reinforcement elements 46.
• the wired working reinforcement elements 46 are arranged side by side substantially parallel to each other.
• Each wired working reinforcement element 46 extends axially from one axial end of the working frame 15 of the tire 10 to the other axial end of the working frame 15 of the tire 10.
• Each wired reinforcing member of work 46 makes a higher angle A T or equal to 10 °, preferably from 30 ° to 50 ° and more preferably from 35 ° to 45 ° with the circumferential direction Z of the tire 10 'in the median plane M.
• a T -40
• the single hoop ply 19 comprises at least one wired hoop reinforcement element 48.
• the hoop ply 19 comprises a single wired hoop reinforcement element 48 wound continuously over an axial width L F from the crown 12 of the tire 10 'so that the axial distance between two adjacent windings is equal to 1, 3 mm.
• the axial width L F is less than the width L T of the working ply 18.
• the hooping ply 19 has a secant module in tension equal to 430 daN.mm 1 for a force equal to 15% of the breaking force of the hooping ply.
• the breaking force of the hooping ply is equal to 69 daN.mm 1 .
• wired carcass reinforcement 44, working 46 and hooping 48 elements are arranged, in the apex 12, so as to define, in projection on the equatorial circumferential plane E in the radial direction of the tire, a triangular mesh.
• Each wired carcass reinforcement element 44 is a textile filament element and conventionally comprises two multifilament strands, each multifilament strand consisting of a yarn of polyester monofilaments, here of PET, these two multifilament strands being individually twisted at 240 towers. m 1 in one direction then twisted together at 240 turns. m 1 in the opposite direction. These two multifilament strands are wound in a helix around one another. Each of these multifilament strands has a titer equal to 220 tex.
• Each wired working reinforcing element 46 is a metallic wired element and is here an assembly of two steel monofilaments each having a diameter equal to 0.30 mm, the two steel monofilaments being wound one with the other in 14 mm steps.
• the wired hoop reinforcement element 48 is obtained by flooding the cable 50 or 50 ’in an elastomeric matrix based on the elastomeric composition of the hoop ply 19.
• the tire 10 ' is manufactured using a process similar to tire manufacturing process 10.
• a specific assembly process is used as described in EP1623819 or else in FR1413102.
• the cables C, E, H, L, M, N, O, P, Q and R according to the invention and obtained by implementing the method of the state of the art described in WO2016083265 and WO2016083267, the cables Q and O being the cables 50 and 50 'respectively described above.
• the diameter Df of each metallic wire element expressed in millimeters was measured, the number N of metallic wire elements, the pitch factor K equal to the ratio of the pitch P over Df, the angle d propeller expressed in degrees, the pitch P of each metallic wire element expressed in millimeters, the propeller diameter Dh expressed in millimeters, the arch diameter Dv expressed in millimeters, the radius of helix curvature Rf expressed in millimeters, the Rf / Df ratio, the Dv / Df ratio, the structural elongation As expressed in%, the cable diameter D expressed in millimeters and a compressibility indicator e c determined as follows.
• the compressibility indicator e c is measured on a test tube with a rectangular section of section 12 mm x 8 mm and a height equal to 20 mm.
• the test piece comprises an elastomeric matrix having, when cooked, a module equal to 10 MPa (here a module representative of the module of the compositions used in tires - in other fields, other modules could be envisaged) and in which is embedded the metallic cable to be tested so that the axis of the cable coincides with the axis of symmetry of the test piece.
• Two support plates of 20 mm x 20 mm section are glued to each side of the rectangular section of the test piece, each side having been carefully ground beforehand.
• Each support plate is then connected to a test machine with a movable cross member that can be used in traction or compression (Zwick or Instron machine for example).
• the test piece (resting on one of the 20 mm x 20 mm plates) is placed on a support with a diameter of 30 mm having a horizontal support face, the support itself fixed on a lower cross member of the test.
• Under the movable crossmember of the machine is placed a force sensor carrying a second support with a diameter equal to 30 mm, the support face, which is also horizontal, is positioned opposite the first.
• the distance between the two horizontal supports is therefore variable according to the movement of the movable cross member.
• This distance takes for the first value, a value such that the specimen can take place effortlessly between the two supports of diameter 30 mm, then takes a second value to exert a preload of 0.1 N, then will decrease to a speed of 3 mm / min until the end of the test, stopped after crushing the test piece by 10% of its initial height.
• the force-compression curve is obtained at 20 ° C. From the value of the force of the specimen is subtracted the contribution of the force of the matrix to the corresponding deformations (from a force-compression curve of the same block in a single matrix). To the value of the maximum force, of this new curve, corresponds the value of maximum deformation where the buckling takes place, critical deformation beyond which the force decreases when the test tube bends.
• the compressibility indicator e c is equal to the value of this critical deformation noted.
• the cable B has a diameter D smaller than the cable C, its longitudinal compressibility is insufficient, in particular because the radius of curvature of the helix Rf and the diameter of the arch Dv are too small, which brings the metallic wire elements too close to the axis of the cable and makes them more likely to burn.
• the cable D has a suitable radius of curvature of the helix Rf, the arch diameter is too small, certainly making the cable very compact but nevertheless very not very compressible longitudinally unlike the cable E according to the invention.
• the cable V although having a relatively small diameter due to the reduced number of metallic wire elements, does not have sufficient longitudinal compressibility.
• cables F, G, H, I By comparing the cables F, G, H, I, it is noted that the cables G and I certainly have relatively small diameters but are nevertheless very little compressible longitudinally due to a particularly small arch diameter Dv and in a lesser measure for cable I, due to a relatively large helix radius of curvature Rf. Cable F has the double defect of a relatively large diameter and low longitudinal compressibility.
• the cable J has a low longitudinal compressibility.
• the cables M, N and O all have a smaller diameter and a much better compressibility.
• the K cable has a relatively small diameter, the K cable is only slightly compressible longitudinally due to its too small arch diameter.
• the cable U has a much too large diameter compared to the cables P, Q and above all R in accordance with the invention.
• the cables S and T although having small diameters D, are very little compressible longitudinally unlike cables P, Q and especially R, the latter having a diameter close to that of the cable S while having a much higher longitudinal compressibility.
• the cable A has a diameter D much too high and a too low longitudinal compressibility.
• the cables B 'and D' if they are smaller, have the same defect of being very little compressible due to an arch diameter Dv too small and of requiring, for the cable D ', preformation stages metallic wire elements. Cable C ', even if it has a diameter larger than that of cables B 'and D', has good longitudinal compressibility.
• the cables E ', F', G ', H', G and J ' By comparing the cables E ', F', G ', H', G and J ', we note that the cables E' and H 'have a diameter D much too high, especially the cables H'.
• the cable F ' has a relatively small diameter but at the cost of insufficient longitudinal compressibility.
• the cables G ', G and J' present an excellent compromise between diameter and longitudinal compressibility, in particular the cable J '.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Ropes Or Cables (AREA)
• Tires In General (AREA)

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• 2019
  • 2019-07-25 CN CN201980046916.1A patent/CN112424419B/zh active Active
  • 2019-07-25 EP EP19745594.2A patent/EP3827125B1/fr active Active
  • 2019-07-25 JP JP2021504261A patent/JP7334234B2/ja active Active
  • 2019-07-25 WO PCT/EP2019/070032 patent/WO2020021006A1/fr not_active Ceased
  • 2019-07-25 KR KR1020217001893A patent/KR102646060B1/ko active Active
  • 2019-07-25 US US17/262,816 patent/US11760128B2/en active Active

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