Shear band with elongated cords for non-pneumatic tires

Abstract

A non-pneumatic tire includes a central rim connecting the tire to a vehicle, a connecting web including a plurality of spokes connected to and extending radially outward from the central rim, and a shear band surrounding and connected to the connecting web. The shear band includes a plurality of elongate cords arranged in parallel layers, each elongate cord having a cross-section defining a lateral width greater than a radial height.

Description

Technical Field

[0001] The present disclosure generally relates to vehicle tires and, more particularly, to shear bands for non-pneumatic tires having high compressive stiffness to reduce rolling resistance. Background Art

[0002] For more than a century, pneumatic tires have been the preferred solution for vehicle mobility. Pneumatic tires are efficient in carrying loads because all the structures of the tire participate in carrying the load. Pneumatic tires are also popular because they have low contact pressure, resulting in less road wear due to the distribution of the vehicle load. Pneumatic tires also have low stiffness, which ensures ride comfort in a vehicle. The main drawback of pneumatic tires is that they require a compressed fluid. Conventional pneumatic tires become inoperable after completely losing inflation pressure.

[0003] Tires designed to operate without inflation pressure can eliminate many of the problems and compromises associated with pneumatic tires. There is no need to maintain or monitor the pressure. Non-pneumatic tires are generally defined by their load-carrying efficiency. "Bottom loaders" are essentially rigid structures that carry most of the load in the structural part under the wheel hub. "Top loaders" are designed such that the entire structure participates in carrying the load. Therefore, the load-carrying efficiency of top loaders is higher than that of bottom loaders, allowing for a lighter-weight design.

[0004] The purpose of the shear band in a non-pneumatic tire is to transfer the load in contact with the ground to the central rim through tension in the spokes or connecting webs, thereby forming a top-loading structure. When the shear band deforms, its preferred form of deformation is shear rather than bending. Non-pneumatic tires typically have a shear band made of a rubber material, which is sandwiched between at least two layers of inextensible belt layers or films. Using rubber in the shear band can significantly increase the cost, weight, and rolling resistance of non-pneumatic tires. Summary of the Invention

[0005] The present disclosure relates to a non-pneumatic tire having a shear band configured to increase the volume of reinforcing material, which may have little or no hysteresis. Oblong cords having a lateral width greater than the radial height can be used to increase the volume of reinforcing material in the shear band. In some embodiments, the cross-section of the oblong cord can be rectangular and tightly packed in parallel layers. By selecting a compound with sufficient stiffness, the thickness of the compound filling the gaps between the oblong cords can be reduced. The oblong cords can be provided as monofilaments composed of a single material or as multifilament cords including a plurality of elongated glass, aromatic polyamide (aramid), and / or carbon fiber filaments embedded in a resin matrix.

[0006] The present disclosure provides, in a first aspect, a non-pneumatic tire. The non-pneumatic tire includes a central rim for receiving a wheel therein or otherwise connecting the tire to a vehicle, a connecting web including a plurality of spokes connected to the central rim and extending radially outward from the central rim, and a shear band surrounding and connected to the connecting web. The shear band includes a plurality of oblong cords arranged in parallel layers, each oblong cord having a cross-section defining a transverse width greater than a radial height.

[0007] The present invention provides the following technical solutions:

[0008] 1. A non-pneumatic tire, comprising:

[0009] A central rim for connecting the tire to a vehicle wheel;

[0010] A connecting web, the connecting web including a plurality of spokes connected to the central rim and extending radially outward from the central rim; and

[0011] A shear band surrounding and connected to the connecting web, the shear band including a plurality of oblong cords arranged in parallel layers, each oblong cord having a cross-section defining a transverse width greater than a radial height.

[0012] 2. The non-pneumatic tire according to solution 1, wherein each oblong cord is a multifilament cord, which includes a plurality of slender glass, carbon fiber and / or aramid filaments embedded in a resin matrix.

[0013] 3. The non-pneumatic tire according to solution 2, wherein the resin matrix includes at least one of epoxy resin, nylon, polyurethane, polyester, vinyl ester, phenolic resin, resorcinol / formaldehyde / latex (RFL) resin.

[0014] 4. The non-pneumatic tire according to solution 1, wherein each oblong cord is a monofilament cord made of nylon or polyester material.

[0015] 5. The non-pneumatic tire according to solution 1, wherein the shear band further includes an elastic compound filling the gaps between the oblong cords.

[0016] 6. The non-pneumatic tire according to solution 5, wherein the elastic compound has a shear modulus G'1% RPA in the range of about 0.5 to about 15 MPa.

[0017] 7. The non-pneumatic tire according to solution 1, wherein the oblong cords in each parallel layer are laterally staggered with the oblong cords in adjacent layers.

[0018] 8. The non-pneumatic tire according to solution 1, wherein the shear band further includes at least one inner belt layer radially arranged between the connecting web and the plurality of oblong cords.

[0019] 9. The non-pneumatic tire according to embodiment 8, wherein the at least one inner belt ply comprises a plurality of elongated steel cord, and the steel cord is inclined at an angle of between approximately -25 degrees and approximately 25 degrees with respect to the main plane of the non-pneumatic tire.

[0020] 10. The non-pneumatic tire according to embodiment 8, wherein the at least one inner belt ply comprises a plurality of aromatic polyamide cord, and the aromatic polyamide cord is inclined at an angle of between approximately -25 degrees and approximately 25 degrees with respect to the main plane of the non-pneumatic tire.

[0021] 11. The non-pneumatic tire according to embodiment 1, wherein the shear band further comprises at least one outer belt ply, and the outer belt ply is disposed radially outward of the plurality of oblong cords.

[0022] 12. The non-pneumatic tire according to embodiment 11, wherein the shear band further comprises a pair of end belt plies covering the lateral edges of the outer belt ply.

[0023] 13. A shear band for a non-pneumatic tire, comprising a plurality of oblong cords arranged in parallel layers, each oblong cord having a cross-section defining a lateral width greater than the radial height.

[0024] 14. The shear band according to embodiment 13, wherein the oblong cords comprise nylon material, polyester material, and / or a plurality of elongated glass, carbon fiber, and / or aromatic polyamide filaments embedded in a resin matrix.

[0025] 15. The shear band according to embodiment 14, wherein the oblong cords are embedded in an elastic compound.

[0026] 16. The shear band according to embodiment 15, wherein the elastic compound exhibits a shear modulus G'1% RPA in the range of approximately 0.5 to approximately 15 MPa.

[0027] 17. The shear band according to embodiment 13, further comprising: a lower belt ply disposed radially inward of the plurality of oblong cords; and an upper belt ply disposed radially outward of the plurality of oblong cords.

[0028] 18. The shear band according to embodiment 17, wherein the lower belt ply comprises at least one of elongated steel cord and / or aromatic polyamide cord, and the cord is inclined at an angle of approximately ±25 degrees with respect to the main plane of the shear band.

[0029] 19. A method of manufacturing a shear band for a non-pneumatic tire, the method comprising:

[0030] Pressing a plurality of filaments together to form a flattened cord having a cross-section defining a transverse width greater than a radial height;

[0031] Heat-treating the flattened cord;

[0032] Arranging the flattened cord in a plurality of parallel circumferential layers to form a shear band.

[0033] 20. The method according to embodiment 19, further comprising embedding a plurality of flattened cords in an elastomeric compound.

[0034] Definition

[0035] The following definitions apply to the present invention.

[0036] "Axial" and "axially" refer to a line or direction parallel to the axis of rotation of the tire.

[0037] "Circumferential" refers to a line or direction extending along the periphery of the tread surface perpendicular to the axial direction.

[0038] "Cord" means: 1) a plurality of filaments twisted or otherwise joined together to form an elongated strip of material; 2) a single filament (monofilament) with or without a coating; or 3) a narrow strip of material with or without twist and / or coating.

[0039] "Equatorial plane (EP)" refers to a plane perpendicular to the axis of rotation of the tire and passing through the center of the tread.

[0040] "Nonextendible" means that a given ply or reinforcing material has an extensional stiffness greater than about 25 Ksi.

[0041] "Transverse" refers to the axial direction.

[0042] "Monofilament" means a cord having only one filament.

[0043] "Flattened" refers to a cross-sectional shape having a relatively large width with respect to its height, or an elongated member having such a cross-section.

[0044] "Oval" refers to a cross-sectional shape having two opposite semi-circles and connected by parallel lines tangent to its endpoints.

[0045] "Radial" and "radially" refer to the radial direction towards or away from the axis of rotation of the tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] The present invention will be described by way of example and with reference to the accompanying drawings, in which:

[0047] Figure 1Is a cross-sectional perspective view of a non-limiting example of a non-pneumatic tire including a shear band constructed of oblong cords according to aspects of the present disclosure.

[0048] Figure 2 Is Figure 1 An enlarged partial cross-sectional view of the shear band, showing the oblong cords of the reinforcing belt layer inserted into the shear band.

[0049] Figure 3A Is Figure 2 An enlarged cross-sectional view of the oblong cord.

[0050] Figures 3B - 3G Is a cross-sectional view of an alternative embodiment of the oblong cord.

[0051] Figure 4 Is a partial cross-sectional view of an alternative embodiment of the shear band that includes one or more SED cord belt layers radially internal to the oblong cord layer.

[0052] Figure 5 Is a partial cross-sectional view of an alternative embodiment of the shear band that includes one or more cover layers disposed on the lateral edges of the shear band.

[0053] Figure 6 Is a schematic view of a manufacturing tool for forming oblong filaments.

[0054] Figure 7 Is a flowchart showing a method of manufacturing a tire assembly according to aspects of the present disclosure. Detailed Description

[0055] Refer to Figure 1 , which shows a non-pneumatic tire 100 according to aspects of the present disclosure. The non-pneumatic tire 100 generally includes a shear band 102, a connecting web 104, and a center rim 106, and may be designed as a top-loading structure such that the shear band 102 and the connecting web 104 effectively carry the operating loads. As described in more detail below, the shear band 102 is constructed of a plurality of oblong cords 110 that reinforce the shear band 102, thereby reducing the rolling resistance of the non-pneumatic tire 100.

[0056] The central rim 106 can have any design and material suitable for accommodating a vehicle's wheel therein or otherwise coupling the non-pneumatic tire 100 to the vehicle. For example, the central rim 106 can generally be configured as a cylindrical member formed of rubber, plastic, or carbon fiber. The cylindrical rim 106 can define a central axis of rotation (not shown) of the non-pneumatic tire 100. The connecting web 104 is disposed radially outward of the central rim 106 and can include a plurality of spokes 112 extending radially outward from the central rim to the shear band 102. As shown, the connecting web 104 includes two circumferentially aligned sets of spokes 112 at the lateral ends of the non-pneumatic tire 100. The spokes 112 can be curved or straight and can have a cross-sectional design different from the generally rectangular spokes 112 shown. In some embodiments, the connecting web 104 can also include connecting rings 114 extending axially between the spokes 112. The connecting rings 114 can be provided to reinforce the non-pneumatic tire 100 in the radial direction and can be composed of a fabric lattice or other structure. In other embodiments, the connecting rings 114 can be omitted. The connecting web 104 (including the spokes 112) can be formed of an elastic material such as rubber or thermoplastic elastomer.

[0057] The shear band 102 is an annular structure that is located radially outside the connecting web 104 and radially inside the tread portion 118 of the non-pneumatic tire 100. The tread portion 118 can or cannot include tread grooves or other patterns for contacting the road surface. The tread portion 118 can include elements such as tread bars, tread blocks, raised patterns, and slits to improve the grip or other performance characteristics of the non-pneumatic tire 100. A layer or tread rubber 120 can be adhered to the radially outer surface of the shear band 102.

[0058] Now referring to Figure 2 , the shear band 102 is shown in cross-section. The shear band 102 is generally composed of oblong cords 110 sandwiched between one or more radially inner belt layers 204 and one or more radially outer belt layers 206. The belt layers 204, 206 can be composed of elongated steel cord 208 embedded in an elastic coating. The elongated steel cord 208 in the radially inner belt layer 204 can be relative to the non-pneumatic tire 100 ( Figure 1) The equatorial plane EP of () is oriented at a first angle, and the range of this first angle is from about 0 to about ±10 degrees, from about 0 to about ±25 degrees. Similarly, the elongate steel cord 208 in the outer belt ply 206 can be oriented at a second angle relative to the equatorial plane EP, and the range of this second angle is from about 0 to about ±10 degrees, from about 0 to about ±25 degrees, and / or from about -20 to about 30 degrees. In some embodiments, the first angle and the second angle extend in opposite directions, while in other embodiments, the first angle and the second angle extend in the same direction. Although the first and second belt plies 204, 206 are described as being constructed of the elongate steel cord 208, in other embodiments, other types of inextensible reinforcing cords can replace the elongate steel cord 208 without departing from the scope of the present disclosure.

[0059] The oblong cords 110 are arranged in a plurality of parallel plies 212. The parallel plies 212 allow the oblong cords 110 to be closely packed, thereby providing a relatively large amount of reinforcing material for the shear band 102. As Figure 2 shown, the oblong cords 110 in each parallel ply 212 are laterally staggered with the oblong cords 110 in adjacent plies 212. This arrangement can provide a relatively rigid shear band 102. In other embodiments, the oblong cords 110 can be arranged in parallel radial columns (not shown) as well as parallel plies 212. An elastomeric compound 214 can be provided to fill the gaps between the oblong cords 110. The elastomeric compound 214 can be formed from a mixture of various components, and the various components are selected to provide the desired stiffness or other properties to the shear band 102. In some embodiments, the compound 214 can have a shear modulus or storage modulus G'1% RPA in the range of about 1.0 MPa to about 42 MPa. In some embodiments, the storage modulus G'1% RPA can be in the range of about 0.5 MPa to about 15 MPa, and more preferably in the range of about 3 MPa to about 7 MPa.

[0060] Now referring to Figure 3A , an exemplary embodiment of an oblong cord 110 having a substantially rectangular cross-section is shown. The oblong cord 110 has a lateral width "W" that is greater than the radial height "H". In some embodiments, the width "W" can be in the range of about 0.7 mm to about 38 mm (about 0.03 to about 1.5 inches), while the height "H" can be in the range of about 0.1 mm to about 18 mm (about 0.004 to about 0.7 inches). The lateral and radial directions are relative to Figure 2The orientation of the oblong cord 110 disposed therein is described, i.e., the width "W" is parallel to the transverse direction and the height "H" is parallel to the radial direction. A larger "W" relative to the height "H" increases the transverse bending stiffness of the oblong cord 110 and the shear band 102 constructed with the oblong cord 110. In other embodiments, the oblong cord 110 may be disposed in other orientations, such as inclined and / or orthogonal to the orientation shown. Figure 3A The oblong cord 110 shown in includes a lower wall 302 and an upper wall 304, as well as substantially flat side walls 306, 308. Fillet 310 is defined at the intersections between the walls 302, 304, 306, 308 such that the oblong cord 110 can be substantially free of sharp corners. Each fillet 310 may have a radius "R", which may be less than half of the radial height "H".

[0061] As Figure 3A shown, the oblong cord 110 is a multifilament cord composed of a plurality of thin and long filaments 314 embedded in a resin matrix 316. The thin and long filaments 314 may be composed of glass, aramid, and / or carbon fiber, and may account for more than 50% of the volume of the oblong cord 110. The resin matrix 316 may include at least one of epoxy resin, nylon, polyurethane, polyester, vinyl ester, phenolic resin, and resorcinol / formaldehyde / latex (RFL) resin, and generally bonds the thin and long filaments 314 to each other. The resin matrix 316 may include a crosslinkable or curable resin, which may be crosslinked or cured by exposure to ultraviolet radiation or heat or by other methods recognized in the art. The resin may be, for example, a mixture of epoxy vinyl ester type, epoxy bisphenol type, epoxy bisphenol A type, and / or epoxy vinyl ester type and epoxy bisphenol type resins. In some exemplary embodiments, the oblong cord 110 is composed of a nylon resin matrix 316 and reinforced with glass or carbon filaments 314. In other embodiments, the oblong cord 110 may be constructed as a monofilament of a single material. For example, the oblong cord may have the same cross-section as that shown in Figure 3A but may be composed of a single material (such as nylon, polyester, aramid, or carbon fiber).

[0062] Now referring to Figures 3B to 3E , a cross-section of other exemplary embodiments of oblong cords 320, 322, 324, and 326 is shown, and the transverse width "W" of each oblong cord is greater than the radial height "H". Figure 3BThe oblong cord 320 shown in [Figure] has an oval cross-section, which includes two semi-circular sides 332, 334 connected by flat lower and upper parallel sides 336, 338. The semi-circular sides 332, 334 are defined by rounded corners 340, and the radius of the rounded corner "R" is equal to half of the radial height "H". In some embodiments, the oblong cord 320 may have a ratio of width "W" to height "H" in the range of 2 to 5. The oblong cord 322( Figure 3C ) may have a standard rectangular cross-section with sharp corners 342 (e.g., corners with a radius "R" equal to zero). The oblong cord 324( Figure 3D ) may have concave sides 344 and 346. The concave side 344 extending across the radial height "H" may have a relatively small radius R minor , while the concave side 346 extending across the transverse width "W" may have a relatively large radius R major . The small radius R minor and the large radius R major can be considered "negative" because the centers of the radii R minor and R major are located outside the cross-section and define the concave side portions of the oblong cord 324. The oblong cord 326 may have an irregular cross-section, such as the V-shaped cross-section shown. The V-shaped cross-section includes two arms 348, 350 extending in opposite directions from the vertex 352. The V-shaped cross-section may allow the oblong cords 326 to interlock with each other when arranged in parallel layers.

[0063] Now referring to Figure 3F and 3G , other exemplary embodiments of oblong cords 354 and 356 are shown, both having a transverse width "W" greater than the radial height "H". The oblong cord 354( Figure 3F ) may have a generally oval cross-section, which defines a perimeter 354. The perimeter 358 centered at the origin (0,0) of the Cartesian coordinate plane can be represented by the following formula 1, where "a" represents the length of the semi-major axis 360 and "b" represents the length of the semi-minor axis 362.

[0064]

[0065] The foci 364 of the ellipse are located at a distance "c" from the origin (0, 0), and the distance "c" can be calculated using the following formula 2.

[0066]

[0067] The eccentricity "e" of the ellipse generally describes the flatness or roundness of the ellipse shape. Generally, the more circular the ellipse, the closer "e" is to zero (0), and the more flattened the ellipse, the closer "e" is to one (1). The eccentricity "e" of the ellipse can be calculated using the following formula 3.

[0068]

[0069] In some embodiments, the eccentricity "e" of the perimeter 354 may be in the range of about 0.6 to about 0.9. A lower eccentricity may not allow the oblong cords 354 to be tightly packed in the shear zone, while a higher eccentricity provides more flexible individual cords 354 than necessary.

[0070] The oblong cord 356( Figure 3G ) may have an irregular elliptical (e.g., egg-shaped) cross-section that defines the perimeter 374. The perimeter 374 is centered at the origin (0,0) of the Cartesian coordinate plane and can be represented by Equation 4 below. Again, "a" represents the length of the semi-major axis 376, "b" represents the length of the semi-minor axis 378, and "t" is a constant much smaller than "a".

[0071]

[0072] The foci 380 of the irregular ellipse (e.g., egg-shaped) are again located at a distance "c" from the origin (0,0), and the distance "c" can be calculated using Equation 2 above. Similarly, the eccentricity "e" of the irregular ellipse can be calculated using Equation 3 above. In some embodiments, the eccentricity "e" of the perimeter 374 may also be in the range of about 0.6 to about 0.9.

[0073] For each oblong cord 110( Figure 3A )、320( Figure 3B )、322( Figure 3C )、324( Figure 3D )、326( Figure 3E )、354( Figure 3F ) and 356( Figure 3G ), it should be understood that variations from these ideal shapes can be envisioned, such as due to manufacturing tolerances and irregularities, without departing from the scope of the present disclosure. Additionally, each oblong cord 110, 320, 322, 324, 326, 354, 356 (and any other cords described herein) may have a surface finish ranging from smooth to rough, which can facilitate interaction with each other or with the compound 214( Figure 2) Adhesion. It is also contemplated that the surface finish may cause the cord to deviate from the above-described ideal or mathematical shape. Similar to the above-described oblong cord 110, oblong cords 320, 322, 324, 326, 354, 356 (and any other cords described herein) can be constructed as monofilaments of a single material (e.g., nylon, polyester, glass, aramid, carbon fiber), or as multifilament cords comprising a plurality of thin, long filaments (e.g., glass, aramid, or carbon fiber) embedded in a resin matrix, twisted together, or otherwise adhered to each other in an oblong shape.

[0074] See Figure 4 , which shows an alternative embodiment of the shear band 402, including one or more inner belt layers 404 made of aramid cord 406 or another material different from the outer belt layer 206. The aramid cord 406 provides the shear band 402 with high-temperature chemical resistance or can provide other performance characteristics. For example, aramid (e.g., aromatic polyamide) can form a cord 406 with high tensile stiffness. Arranging the aramid cord 406 at the bottommost part (near the radially innermost edge) of the shear band 402 can maximize the benefit of its high tensile stiffness, since the radially innermost edge of the shear band 402 is subjected to tensile forces during operation. These cords 406 will strengthen the shear band 402 and resist these tensile forces. In some embodiments, the cord 406 can be made of nylon resin. Nylon is an aliphatic polyamide that may shrink when heated (e.g., due to operating stress). The shrinkage ability of the cord 406 can resist the growth of the shear band 402 and the tire constructed with the shear band 402.

[0075] The outer belt layer 206 can be composed of elongated steel cord 208 embedded in an elastic coating, as described above. The aramid cord 406 can be larger in diameter than the steel cord 208 and can be tackified to hold the aramid cord 406 in place when constructing the shear band 402. The aramid cord 406 (or any other cord described herein) can be tackified by various methods recognized in the art, such as coating the cord 406 in an aqueous mixture of rosin and rubber lattice, or coating it with a solvent solution or emulsion of an uncured rubber compound. In some embodiments, the aramid cord 406 can be inclined relative to the equatorial plane EP of the tire ( Figure 2 ) in a range of about -25 degrees to about 25 degrees, -10 degrees to about 10 degrees, and / or -20 degrees to about 30 degrees.

[0076] Between the inner belt layer 404 and the outer belt layer 206, the shear band 402 includes one or more parallel layers 212 made of oblong cord 110 as described above. In other embodiments, the oblong cord 110 can be replaced with the above-described oblong cord 320 ( Figure 3B ), 322 (Figure 3C )、324( Figure 3D )、326( Figure 3E )、354( Figure 3F ) or 356( Figure 3F ), or a combination of the elongated cords 110, 320, 322, 324, 326, 354, 356 with each other, without departing from the scope of the present disclosure.

[0077] See Figure 5 , which shows an alternative embodiment of the shear band 502, which includes a pair of end belt plies 504 that cover the lateral edges 506a, 506b of the outer belt ply 206. In some embodiments, the end belt plies 504 include steel cords 508 or other filaments that extend at an angle in the range of about 0 to about ±10 degrees relative to the equatorial plane EP( Figure 2 ), and in some embodiments, the extension angle is in the range of about 0 to about ±5 degrees. The end belt plies 504 can limit the movement of the outer belt ply 206 at the lateral edges 506a, 506b, thereby reducing stress, fatigue, and heat generation during the use of the shear band 502. Reducing stress can reduce the risk of the outer belt ply 206 separating from the edges of adjacent layers. The shear band 502 can also include one or more parallel layers 212 formed of the elongated cords 110 as described above and one or more inner belt plies 404.

[0078] See Figure 6 , which shows a schematic view of an exemplary manufacturing tool 600 for forming the elongated cords 110, 320, 322, 324, 326, 354, 356. The manufacturing tool 600 includes a pressure roller 602 and a forming roller 604. The forming roller 604 can include circumferential notches 606 defined therein, the dimensions and shape of the width and depth of which are similar to the lateral width "W" and radial height "H" of the desired elongated cord. As Figure 6 shown, the circumferential notches 606 are generally rectangular and can be used to form the elongated cord 110. In other embodiments, the dimensions or shape of the circumferential notches 606 can be designed to form any other elongated cord 320, 322, 324, 326, 354, 356 or any other multifilament cord described herein. One or both of the pressure roller 602 and the forming roller 604 can include heaters therein, for example, resistance heaters (not shown), or in other embodiments, different heaters (not shown) can be provided near the rollers 602, 604.

[0079] The pressure roller 602 and the forming roller 604 are engaged with each other and can rotate in opposite directions, e.g., in the directions of arrows 608, 610, to feed a plurality of resin-coated filament bundles 612 into the circumferential notches 606. The filament bundle 612 can include one or more filaments 314 (Figure 3), which can include glass filaments, aramid filaments, and / or carbon fiber filaments as described above. By heating the resin-coated bundle 612 and applying pressure with the rollers 602, 604, a flat elongated cord 110 can be formed.

[0080] In other embodiments, the multifilament flat elongated cords 110, 320, 322, 324, 326, 354, 356 can be constructed using pultrusion techniques and equipment. Pultrusion is a processing technique for forming and manufacturing continuous lengths of fiber-reinforced polymers (FRPs) by pulling a mixture of reinforcing fibers (e.g., glass, aramid, and / or carbon fibers) and a liquid resin through a heated die (not shown). This process produces cords having a constant cross-section, such as tubes, rods, beams, and / or Figures 3A to 3F any of the shapes shown in. The shape of the heated die and the type of resin matrix can be varied to produce flat elongated cords 110, 320, 322, 324, 326, 354, 356 having the desired performance characteristics.

[0081] Now referring Figure 7 , an example procedure 700 for manufacturing a tire assembly in accordance with aspects of the present disclosure is shown. Procedure 700 begins at step 702, where a glass filament bundle is coated with resin. The bundles can then be pressed together (step 704) and formed into a flat elongated cord. For example, the bundles can be pressed together using a forming roller or a die in pultrusion manufacturing equipment. Next, in step 706, a surface finish is applied and the flat elongated cord is heat-treated. It should be understood that steps 702, 704, and 706 can be performed in sequence, simultaneously, and in an order different from the order shown.

[0082] Then, procedure 700 proceeds to step 708, where the finished flat elongated cord is wound onto a spool for storage or transportation. In some embodiments, step 708 can be omitted, and procedure 700 proceeds directly to step 710, where the flat elongated cord is placed into the shear band of a non-pneumatic tire assembly. The flat elongated cords can be placed in parallel circumferential layers, and the flat elongated cords in each layer can be laterally staggered with respect to the flat elongated cords in adjacent layers. A compound can then be placed between the flat elongated cords in the shear band. The tire assembly can be completed by mounting an upper and / or lower belt layer to the shear band, mounting a tread, and / or by mounting the shear band to a central rim and connecting webs.

[0083] Unless otherwise indicated, all numbers expressing quantities of ingredients, properties such as molecular weight, reaction conditions, etc., used in the specification and the related claims are to be understood as being modified in all instances by the term "about". Accordingly, unless indicated to the contrary, the numerical parameters set forth in the following specification and attached claims are approximations that may vary depending upon the desired properties sought to be obtained by the present invention. At the very least, and not as an attempt to limit the application of the doctrine of equivalents to the scope of the claims, each numerical parameter should at least be construed in light of the number of reported significant digits and by applying ordinary rounding techniques.

[0084] Although the compositions and methods are described herein in terms of "comprising" various components or steps, the compositions and methods can also "consist essentially of" or "consist of" the various components and steps.

[0085] The present invention may be varied in accordance with the description herein. While certain representative embodiments and details have been shown for the purpose of illustrating the subject invention, it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the scope of the subject invention. Accordingly, it is to be understood that changes may be made in the particular embodiments described which will fall within the full scope of the invention as defined by the appended claims.

Claims

1. A non-pneumatic tire comprising: a central rim for attaching the tire to the vehicle's wheel; a connecting web including a plurality of spokes connected to the center rim and extending radially outward from the center rim; as well as A shear tie surrounds and is connected to the connecting web, the shear tie comprising a plurality of elongated cords arranged in parallel layers, each elongated cord having a cross-section defining a transverse width greater than a radial height.

2. The non-pneumatic tire of claim 1, wherein each of the flat elongated cords is a multifilament cord comprising a plurality of elongated glass, carbon fiber and / or aromatic polyamide filaments embedded in a resin matrix.

3. The non-pneumatic tire of claim 2, wherein the resin matrix comprises at least one of epoxy resin, nylon, polyurethane, polyester, vinyl ester, phenolic resin, resorcinol / formaldehyde / latex (RFL) resin.

4. The non-pneumatic tire according to claim 1, wherein each of the oblong cords is a monofilament cord composed of nylon or polyester material.

5. The non-pneumatic tire of claim 1, wherein the shear band further comprises an elastomeric compound filling gaps between the elongated cords.

6. The non-pneumatic tire of claim 5, wherein the elastomeric compound has a shear modulus G'1% ​​RPA in the range of about 0.5 to about 15 MPa.

7. The non-pneumatic tire of claim 1, wherein the elongated cords in each parallel layer are transversely staggered with the elongated cords in an adjacent layer.

8. The non-pneumatic tire of claim 1, wherein the shear band further comprises at least one inner belt layer radially disposed between the connecting web and the plurality of elongated cords.

9. A shear belt for a non-pneumatic tire comprising a plurality of elongated cords arranged in parallel layers, each elongated cord having a cross-section defining a transverse width greater than a radial height.

10. A method of making a shear band for a non-pneumatic tire, the method comprising: pressing a plurality of filaments together to form an elongated cord having a cross-section defining a transverse width greater than a radial height; Heat treatment of the flat long cord; The oblong cords are arranged in multiple parallel circumferential layers to form shear bands.

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