System and method for manufacturing a band and tread assembly for a non-pneumatic tire

Abstract

A system for assembling a circumferential tread and band for a non-pneumatic tire includes a curing wrap sized to receive the band and the circumferential tread for the non-pneumatic tire. The curing wrap includes a valve. The system also includes a fastener configured to secure a first side of the curing wrap to the circumferential tread and a second side of the curing wrap to the first side of the curing wrap.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE This disclosure relates to non-pneumatic tires and systems and methods of manufacturing the same, and more particularly, to systems and methods of applying tread to bands for non-pneumatic tires. [Background technology]

[0002] Various tire designs have been developed that allow the tire to run in an uninflated or underinflated state. Non-pneumatic tires do not require inflation, while "run-flat tires" can continue to operate at relatively high speeds for extended periods of time after a puncture that completely or partially loses pressurized air. Non-pneumatic tires may include multiple spokes, webbing, or other support structures connecting a lower ring to an upper ring. It is known to use adhesives or cements to adhere a pre-cured tread to a non-pneumatic upper ring. Summary of the Invention

[0003] In one embodiment, a method of manufacturing a band and tread assembly for a non-pneumatic tire includes providing a band and providing an elastomeric tread circumferentially around an upper surface of the band. The method further includes providing a flexible wrap having a valve extending therefrom. The flexible wrap has a first end and a second end. The method also includes disposing the flexible wrap around the band and the elastomeric tread such that the first end overlaps the second end. The method further includes securing the flexible wrap around the band and the elastomeric tread and applying heat within the flexible wrap.

[0004] In another embodiment, a system for assembling a circumferential tread and band for a non-pneumatic tire includes a curing wrap sized to receive the band and the circumferential tread for the non-pneumatic tire. The curing wrap includes a valve. The system also includes a fastener configured to secure a first side of the curing wrap to the circumferential tread and a second side of the curing wrap to the first side of the curing wrap.

[0005] In yet another embodiment, a method of manufacturing a non-pneumatic tire includes providing an upper band and providing an elastomeric tread circumferentially about an upper surface of the upper band. The method further includes securing a curing wrap around the elastomeric tread and upper band and applying heat within the curing wrap to form the upper band and tread assembly. The method also includes providing a support structure connected to the lower band and affixing the upper band and tread assembly to the support structure. [Brief explanation of the drawings]

[0006] The accompanying drawings, together with the detailed description provided below, illustrate structures that describe exemplary embodiments of the claimed invention. Similar elements are identified with the same reference numerals. It should be understood that elements shown as a single component may be replaced by multiple components, and that elements shown as multiple components may be replaced by a single component. The drawings are not to scale, and the proportions of certain elements may be exaggerated for illustrative purposes. [Figure 1] FIG. 1 is a front view of one embodiment of a non-pneumatic tire. [Figure 2] FIG. 2 is a front view of an alternative embodiment of a non-pneumatic tire. [Figure 3] FIG. 3 is a schematic diagram illustrating a front view of one embodiment of a tread and upper band assembly for a non-pneumatic tire. [Figure 4] FIG. 4 is a perspective view of a curing wrap secured around a tread and upper band assembly for a non-pneumatic tire. [Figure 5] FIG. 5 is a partial perspective view of the interior of a curing wrap secured around a tread and upper band assembly for a non-pneumatic tire. DETAILED DESCRIPTION OF THE INVENTION

[0007] The following contains definitions of selected terms used herein. These definitions include various examples and / or forms of components that fall within the scope of the term and that may be used for implementation. The examples are not intended to be limiting. Both the singular and plural forms of a term may be within the scope of the definition.

[0008] "Axial" and "axially" refer to directions parallel to the axis of rotation of the tire.

[0009] "Circumferential" and "circumferentially" refer to a direction extending along the perimeter of the surface of the tread perpendicular to the axial direction.

[0010] "Radial" and "radially" refer to directions perpendicular to the axis of rotation of the tire.

[0011] As used herein, "tread" refers to that portion of the tire that comes into contact with the road or ground under normal inflation and normal load.

[0012] It should be understood that while similar terms are used in the following description to describe typical tire components, the terms, of course, have slightly different connotations and one of ordinary skill in the art would not consider any of the following terms to be purely interchangeable with another term used to describe a typical tire component.

[0013] As used herein, directions are stated with reference to the tire's axis of rotation. The terms "upward" and "upwardly" refer to the general direction toward the tire's tread, and "downward" and "downwardly" refer to the general direction toward the tire's axis of rotation. Thus, when relative directional terms such as "upper" and "lower" or "top" and "bottom" are used in connection with elements, the "upper" or "top" element is spaced closer to the tread than the "lower" or "bottom" element. Additionally, when relative directional terms such as "above" or "below" are used in connection with elements, an element that is "above" another element is closer to the tread than the other element.

[0014] The terms "inward" and "inwardly" refer to the general direction toward the tire's equatorial plane, and "outward" and "outwardly" refer to the general direction away from the tire's equatorial plane, toward the tire's sidewall. Thus, when relative directional terms such as "inner" and "outer" are used in connection with elements, the "inner" elements are spaced closer to the tire's equatorial plane than the "outer" elements.

[0015] 1 illustrates one embodiment of a non-pneumatic tire 10. The non-pneumatic tire 10 is merely an exemplary illustration and is not intended to be limiting. In the illustrated embodiment, the non-pneumatic tire 10 includes a generally annular lower ring 20 that engages a rim (not shown) on which the tire 10 is mounted. The generally annular lower ring 20 has an inner surface 23 and an outer surface 24 and may be made from an elastomeric material or metal.

[0016] The non-pneumatic tire 10 further includes a generally annular upper ring 30 surrounding interconnected webs 40, which are support structures connected to the generally annular lower ring 20. In alternative embodiments, a plurality of spokes or other support structures connect the lower ring to the upper ring. The upper ring 30 can be configured to deform in a region 48 around and including the contact patch region 32, thereby reducing vibrations and improving ride comfort.

[0017] In one embodiment, the generally annular lower ring 20 and the generally annular upper ring 30 are made from the same material as the interconnected webs 40. In one particular embodiment, the lower ring 20, the upper ring 30, and the webs 40 are each constructed of steel. In alternative embodiments, the lower ring 20, the upper ring 30, and the webs 40 are each constructed from other metals, carbon fiber, resins, or polymeric materials such as polyurethane, polyester, nylon, or polyvinyl chloride (PVC). However, it should be understood that other materials may be used and the rings and spokes are not limited to the listed materials.

[0018] In an alternative embodiment, at least one of the generally annular lower ring, the generally annular upper ring, and the interconnected webs are made from different materials. For example, the upper ring 30 may be a steel band, while the lower ring 20 and webs 40 are constructed from other metals, carbon fiber, resins, or polymeric materials such as polyurethane, polyester, nylon, or polyvinyl chloride (PVC).

[0019] In the illustrated embodiment, the interconnected web 40 has at least two radially adjacent layers 56, 58 of web elements 42 that define a plurality of generally polygonal openings 50. In other embodiments (not shown), other web configurations may be used.

[0020] As shown in FIG. 1 , the generally annular top ring 30 may have a radially outer surface 34 to which a circumferential tread 70 is attached. The circumferential tread 70 may be constructed of an elastomeric material, such as natural or synthetic rubber. The tread 70 may have a plurality of circumferential grooves that define a plurality of ribs. It should be understood that the tread may include tread elements such as grooves, ribs, blocks, lugs, sipes, studs, and other elements. Shear bands or other shear elements or reinforcing structures (not shown) may be disposed between the top ring 30 and the tread 70. Alternatively, the shear bands or other shear elements may be disposed within the tread.

[0021] In one embodiment, the circumferential tread 70 is affixed to the top of the upper ring 30 without a pressure sensitive adhesive disposed between the upper ring 30 and the circumferential tread 70. In one such embodiment, the circumferential tread 70 is bonded directly to the top of the upper ring 30. In another such embodiment, a strip of cured rubber (not shown) or a heat sensitive adhesive is disposed between the circumferential tread 70 and the upper ring 30.

[0022] 2 is a front view of an alternative embodiment of a non-pneumatic tire 100. The non-pneumatic tire 100 includes an inner ring 110 having a first diameter and an outer ring 120 having a second diameter larger than the first diameter. The outer ring 120 is substantially coaxial with the inner ring 110. In the illustrated embodiment, the inner ring 110 is shown attached to a hub H. A plurality of spokes 130 extend between the inner ring 110 and the outer ring 120. It should be understood that the term "support structure" can refer to either a webbing (such as the web 40 in FIG. 1) or spokes (such as the spokes 130 in FIG. 2).

[0023] In one embodiment, the lower ring 110, the upper ring 120, and the spokes 130 are each constructed from the same material. In one particular embodiment, the lower ring 110, the upper ring 120, and the spokes 130 are each constructed from steel. In alternative embodiments, the lower ring 110, the upper ring 120, and the spokes 130 are each constructed from other metals, carbon fiber, resins, or polymeric materials such as polyurethane, polyester, nylon, or polyvinyl chloride (PVC). However, it should be understood that other materials may be used, and the rings and spokes are not limited to the listed materials.

[0024] In alternative embodiments, one or more of the lower ring 110, upper ring 120, and spokes 130 are constructed from different materials. For example, the upper ring 120 may be a steel band, while the lower ring 120 and spokes 130 are constructed from other metals, carbon fiber, resin, or polymeric materials such as polyurethane, polyester, nylon, or polyvinyl chloride (PVC).

[0025] In the illustrated embodiment, a circumferential tread 140 is disposed about the top ring 120. The circumferential tread 140 may be constructed of an elastomeric material, such as natural or synthetic rubber. The tread 140 may have a plurality of circumferential grooves that define a plurality of ribs. It should be understood that the tread may include tread elements such as grooves, ribs, blocks, lugs, sipes, studs, and other elements. Shear bands or other shear elements or reinforcing structures (not shown) may be disposed between the top ring 120 and the tread 140. Alternatively, the shear bands or other shear elements may be disposed within the tread.

[0026] In one embodiment, the circumferential tread 140 is affixed to the top of the upper ring 120 without a pressure sensitive adhesive disposed between the upper ring 120 and the circumferential tread 140. In one such embodiment, the circumferential tread 140 is bonded directly to the top of the upper ring 120. In another such embodiment, a strip of cured rubber (not shown) or a heat sensitive adhesive is disposed between the circumferential tread 140 and the upper ring 120.

[0027] To manufacture a non-pneumatic tire, such as tire 10 or tire 100, a manufacturer provides a band (such as top ring 30 or top ring 120) and an elastomeric tread (such as tread 70 or tread 140) and then wraps the tread around the top ring. The manufacturer then provides a flexible wrap having a first end and a second end and places the wrap around the band and elastomeric tread so that the first end overlaps the second end. The manufacturer then secures the wrap around the band and elastomeric tread and applies heat within the wrap.

[0028] After the elastomeric tread is cured into the band, the manufacturer provides a tire structure that includes a lower ring (such as lower ring 20 or lower ring 110) having a diameter smaller than that of the band and a support structure (such as web 40 or spokes 130) extending from the lower ring. The manufacturer then affixes the band to the support structure. For example, the manufacturer may affix the band to the support structure using an adhesive or through a welding or brazing process.

[0029] 3 is a schematic diagram illustrating a front view of one embodiment of a pre-cure assembly 200 including a band 210 having a tread 220 extending around the circumference of the band. The band 210 may be the same as the top ring 30 or top ring 120 of FIGS. 1 and 2. The tread 220 may be the same as the tread 70 or tread 140 of FIGS. 1 and 2, except that the tread 220 may be in an uncured or partially cured state. Alternatively, the tread 220 may be a cured tread.

[0030] In one embodiment, a strip of green rubber or heat sensitive adhesive (not shown) is first applied to either the tread 220 or the band 210. In an alternative embodiment, the tread 220 is placed directly onto the band 210.

[0031] 4 and 5 provide a perspective view and a partial perspective view, respectively, of a curing wrap 300 secured around a pre-cure assembly of a tread and upper band assembly for a non-pneumatic tire. The curing wrap 300 is sized to receive the circumferential tread and band. The curing wrap 300 has a valve 310, a first end, and a second end.

[0032] The stiffening wrap 300 may be a sheet of butyl rubber, other rubber compound, neoprene, polythread, latex, or other flexible material. The sheet of material may have a thickness of 0.008 inches (0.02 cm) to 0.12 inches (0.3 cm). The stiffening wrap 300 may also be formed from multiple sheets of material.

[0033] The curing wrap 300 is placed around the pre-cured assembly of the band and elastomeric tread such that the first end overlaps the second end. In one embodiment, the first side of the curing wrap 300 overlaps the second side of the curing wrap by a distance of 2-3 inches (5-8 cm). The curing wrap 300 is then secured around the band and elastomeric tread.

[0034] In the illustrated embodiment, the cure wrap 300 is placed around the pre-cured assembly of the band and elastomeric tread such that the first end overlaps the second end above the elastomeric tread. The cure wrap 300 is then secured with straps 320. In this embodiment, the valve 310 extends below the band, as shown in FIG. 5. In an alternative embodiment, the valve may extend above the elastomeric tread.

[0035] In an alternative embodiment, the cure wrap is placed around the pre-cured assembly of the band and elastomeric tread such that the first end overlaps the second end below the band. In such an embodiment, the cure wrap may be secured by a fastener such as an arcuate band. In one such embodiment, the valve may extend above the elastomeric tread. In another embodiment, the valve may extend below the band.

[0036] In either embodiment, heat and pressure are applied within the cure envelope after the cure envelope is secured to the pre-cured assembly of band and elastomeric tread. In one embodiment, heat is applied at a temperature of 200°F to 300°F (90°C to 150°C). The elastomeric tread may be a pre-cured or partially cured tread, with any desired tread elements pre-formed before the tread is placed around the upper ring. Because the elastomeric tread is pre-cured or partially cured, the tread is only heated to a temperature sufficient to bond the tread to the upper ring.

[0037] The terms "includes" or "including," to the extent that they are used herein or in the claims, are intended to be inclusive, similar to the term "comprising," as interpreted when used as a transitional term in a claim. Furthermore, to the extent that the term "or" is used (e.g., A or B), it is intended to mean "A or B, or both." Where applicants intend to indicate "only A or B but not both," the term "only A or B but not both" is used. Thus, the use of the term "or" herein is inclusive, not exclusive. See Bryan Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). Also, to the extent that the terms "in" or "into" are used herein or in the claims, they are intended to additionally mean "on" or "onto." Furthermore, to the extent the term "connect" is used in this specification or the claims, it is intended to mean not only "directly connected to," but also "indirectly connected to," such as by connecting through one or more other components.

[0038] While the present application has been illustrated by the description of its embodiments, and those embodiments have been described in considerable detail, it is not the intention of the applicants to restrict or in any way limit the scope of the appended claims to such details. Additional advantages and modifications will be readily apparent to those skilled in the art. Therefore, the present application in its broader aspects is not limited to the specific details, representative apparatus and methods, and examples shown and described. Accordingly, departures may be made from such details without departing from the spirit or scope of the applicant's general inventive concept.

Claims

1. 1. A method of manufacturing a band and tread assembly for a non-pneumatic tire, comprising: providing an annular band; providing an elastomeric tread circumferentially around an upper surface of said band; providing a flexible wrap having a valve extending therefrom, said flexible wrap having a first end and a second end; placing the flexible wrap around an inner periphery of the band and an outer periphery of the elastomeric tread such that the first end overlaps the second end; securing the flexible wrap around the band and the elastomeric tread; and applying heat within said flexible wrap.

2. 2. The method of claim 1, wherein the flexible wrap is positioned around the band and the elastomeric tread such that the first end overlaps the second end above the elastomeric tread, and wherein securing the flexible wrap around the band and the elastomeric tread comprises securing the flexible wrap with a strap.

3. The method of claim 1 , wherein securing the flexible wrap around the band and the elastomeric tread comprises securing the flexible wrap with an arcuate band.

4. The method of claim 1 , wherein the flexible wrap is disposed around the band and the elastomeric tread such that the valve extends under the band.

5. The method of claim 1 further comprising applying pressure within the flexible wrap.

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