The present disclosure relates to a non-pneumatic tire having reinforced support structure and a method of making the same. More particularly, the present disclosure relates to a non-pneumatic tire having reinforced spokes or webbing having reinforcements at least partially wrapped around elongated members, and a method of making the same.
Various tire constructions have been developed which enable a tire to run in an uninflated or underinflated condition. Non-pneumatic tires do not require inflation, while “run flat tires” may continue to operate after receiving a puncture and a complete or partial loss of pressurized air, for extended periods of time and at relatively high speeds. Non-pneumatic tires may include a plurality of spokes, a webbing, or other support structure that connects an inner ring to an outer ring.
In one embodiment, a non-pneumatic tire and rim assembly includes a non-pneumatic tire having a ring, a circumferential tread disposed about the ring, and a plurality of spokes extending radially downward from the ring. Each spoke terminates at a lower end defined by an axially extending member. Each spoke includes a reinforcement at least partially wrapping around the axially extending member. The reinforcement may be a plurality of cords of reinforcement material, a mesh of reinforcement material, or a sheet of reinforcement material. The assembly also includes a rim having a plurality of mounts. Each mount is configured to receive the axially extending member of a corresponding spoke.
In another embodiment, a method of making a non-pneumatic tire includes the steps of providing a ring, providing a plurality of elongated members, and arranging the elongated members inside the ring, such that each elongated member extends in an axial direction relative to the ring. The method also includes providing a ribbon of reinforcement material, and wrapping the ribbon of reinforcement material along a circuitous path along an inner surface of the ring and around each of the elongated members.
In yet another embodiment, a non-pneumatic tire includes a ring, a circumferential tread disposed about the ring, and a plurality of support structures extending downwards from the ring. An end of each support structure includes an axially extending member, and each support structure includes a reinforcement layer extending along a length of the support structure and wrapping around the axially extending member.
In the accompanying drawings, structures are illustrated that, together with the detailed description provided below, describe exemplary embodiments of the claimed invention. Like elements are identified with the same reference numerals. It should be understood that elements shown as a single component may be replaced with multiple components, and elements shown as multiple components may be replaced with a single component. The drawings are not to scale and the proportion of certain elements may be exaggerated for the purpose of illustration.
The following includes definitions of selected terms employed herein. The definitions include various examples and/or forms of components that fall within the scope of a term and that may be used for implementation. The examples are not intended to be limiting. Both singular and plural forms of terms may be within the definitions.
“Axial” and “axially” refer to a direction that is parallel to the axis of rotation of a tire.
“Circumferential” and “circumferentially” refer to a direction extending along the perimeter of the surface of the tread perpendicular to the axial direction.
“Radial” and “radially” refer to a direction perpendicular to the axis of rotation of a tire.
“Tread” as used herein, refers to that portion of the tire that comes into contact with the road or ground under normal inflation and normal load.
While similar terms used in the following descriptions describe common tire components, it should be understood that because the terms carry slightly different connotations, one of ordinary skill in the art would not consider any one of the following terms to be purely interchangeable with another term used to describe a common tire component.
Directions are stated herein with reference to the axis of rotation of the tire. The terms “upward” and “upwardly” refer to a general direction towards the tread of the tire, whereas “downward” and “downwardly” refer to the general direction towards the axis of rotation of the tire. Thus, when relative directional terms such as “upper” and “lower” or “top” and “bottom” are used in connection with an element, 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 an element, an element that is “above” another element is closer to the tread than the other element.
The terms “inward” and “inwardly” refer to a general direction towards the equatorial plane of the tire, whereas “outward” and “outwardly” refer to a general direction away from the equatorial plane of the tire and towards the sidewall of the tire. Thus, when relative directional terms such as “inner” and “outer” are used in connection with an element, the “inner” element is spaced closer to the equatorial plane of the tire than the “outer” element.
In an alternative embodiment (not shown), the ring itself forms the tread of tire. As such, it may include ribs, blocks, grooves, sipes, or other tread elements (not shown).
In the illustrated embodiment, a plurality of support structures in the form of spokes 130 extend downward (i.e., towards the axis of rotation) from the ring 110. In the illustrated embodiment, each spoke 130 extends axially across the entire ring 110. In an alternative embodiment, each spoke extends only partially across the ring. In one such embodiment, two or more rows of spokes may be employed. The rows may be aligned with each other or offset from each other.
In the illustrated embodiment, the spokes 130 are substantially linear and extend in a radial direction. In alternative embodiments, the spokes may be curved or disposed at an acute angle relative to the radial direction. The spokes may also be V-shaped, crisscrossed, or have any geometric shape. Alternatively, a webbing or other support structure may be employed.
Each spoke 130 terminates at a lower end having an elongated member 140. In the illustrated embodiment, the elongated members 140 are axially extending members. In alternative embodiments (not shown), the elongated members may extend in a non-axial direction.
The elongated members 140 define an inner diameter of the tire 100. In the illustrated embodiment, each elongated member 140 is a cylindrical rod, such as a pin, a post, a tab, or a threaded rod.
The non-pneumatic tire 100 further includes a reinforcement layer 150 extending along the ring 110 and the spokes 130. The reinforcement layer 150 at least partially wraps around each elongated member 140. The reinforcement layer 150 may take the form of a plurality of cords of reinforcement material, a mesh of reinforcement material, and a sheet of reinforcement material. Exemplary reinforcement material includes steel or other metal, nylon, polyester, fiberglass, carbon fiber, aramid, glass, polyethylene (polyethylene terephthalate). However, the reinforcement layer is not limited to any particular reinforcement material.
To build the non-pneumatic tire 100, the reinforcement layer 150 may be first embedded in the embedding material. For example, the reinforcement layer may be co-extruded with a green elastomeric material to form a green, reinforced ribbon. Alternatively, the reinforcement layer 150 may be a separate layer used in a tire build, which is then overlaid with the embedding material. For example, a ribbon or sheet of reinforcement material may be applied to the tire build and then a ribbon or sheet of embedding material may then be applied to the reinforcement layer. The tire build may then be cured in a vulcanization mold or autoclave, or through other curing means. As another example, a ribbon or sheet of reinforcement material may be applied to the tire build and then the tire build may be over molded with embedding material in an injection mold or compression mold.
In one embodiment, the reinforcement layer is a plurality of cords that are embedded in a ribbon of green elastomeric material. In one specific embodiment, the cords extend in a longitudinal direction of the ribbon. In such an embodiment, the cords would extend in a radial direction along each spoke. In alternative embodiments, the cords may be biased with respect to the longitudinal direction or may extend in a lateral direction. In such an embodiment, the cords would extend in a biased direction or a lateral direction along each spoke.
In all embodiments, the embedding material may be further coated with a protective material. For example, the embedding material may be coated with a material formulated to have material properties that are better at withstanding exposure to the ozone than the embedding material. Such material may include tire sidewall compound, veneer compound, synthetic rubber such as ethylene propylene diene monomer (EPDM) rubber, neoprene, butyl rubber, a hydrogenated diene rubber, or other compounds formulated to withstand exposure to ozone. The coating may be a different color from the embedding material.
While a single reinforcement layer 150 is shown in
The skeleton 200 is for illustrative purposes only, to show the relationship between the reinforcement layer 150 and other elements of the non-pneumatic tire 100. While the skeleton 200 may represent a partial build according to one method of making a reinforced tire, it is merely presented here to illustrate what the tire 100 would theoretically look like if all embedding material could be removed.
In the illustrated embodiment, the reinforcement layer 150 is shown as a mesh. The reinforcement layer 150 is illustrated as a serpentine ribbon that is disposed continuously about a central axis of the skeleton 200, and following a winding path along an inner portion of the skeleton ring 210 and about the elongated member 140 of each skeleton spoke 230. In the illustrated embodiment, the reinforcement layer 150 follows a substantially radial path from the skeleton ring 210 to the elongated member 140. In alternative embodiments, the reinforcement layer may follow a non-radial path from the skeleton ring to the elongated member. For example, the reinforcement layer may follow a curved or an angled path.
In one embodiment, the reinforcement layer 150 is adhered to each elongated member 140 with an adhesive or through a curing process or a chemical bond. In such embodiments, the reinforcement layer 150 may be directly adhered to the elongated member 140, or an embedding material containing the reinforcement layer may be adhered to the elongated member 140.
In an alternative embodiment, the reinforcement layer 150 is not adhered to the elongated member 140. In such an embodiment, the elongated member 140 is free to rotate or translate with respect to the reinforcement layer 150. The mechanical interaction between the elongated member 140 and the reinforcement layer 150 may thus be selected to achieve different performances. In some embodiments, it may be desirable for the elongated member to be fixed with respect to the reinforcement layer. In other embodiments, it may be desirable for the elongated member to rotate with respect to the reinforcement layer, without translating. In still other embodiments, it may be desirable for the elongated member to translate with respect to the reinforcement layer, without rotating. In still other embodiments, it may be desirable for the elongated member to rotate and translate with respect to the reinforcement layer.
With continued reference to
The reinforcement layer 800 is substantially the same as the other reinforcement layers described above, except the reinforcement layer 800 defines a portion of a web instead of a radially extending spoke. The reinforcement layer 800 may be a continuous layer that wraps around a series of rigid members forming a webbing. Alternatively, the reinforcement layer 800 may be formed by a plurality of reinforcement layers. For example, any of the multi-layer embodiments shown and described with respect to
The reinforcement layer 900 is substantially the same as the other reinforcement layers described above, except instead of defining a radially extending spoke the reinforcement layer 800 defines a curved spoke. The reinforcement layer 900 may be a continuous layer that wraps around each of the plurality of elongated members 140 of the tire. Alternatively, the reinforcement layer 900 may be formed by a plurality of reinforcement layers. For example, any of the multi-layer embodiments shown and described with respect to
In the illustrated embodiment, the bead filler 910 is in contact with the elongated member 140. In an alternative embodiment, the bead filler is spaced from the elongated member.
In the illustrated embodiment, the bead filler 910 is shown as having a substantially triangular shape and a height that is approximately equal to the diameter of the elongated member 140. It should be understood, however, that the shape and the dimensions of the bead filler may be varied to achieve a desired performance. For example, the bead filler 910 may have a height that is less than 20% of the height of a spoke. In another embodiment, the bead filler 910 may have a height equal to 20-40% of the height of a spoke. In another embodiment, the bead filler 910 may have a height equal to 40-60% of the height of a spoke. In another embodiment, the bead filler 910 may have a height equal to 60-80% of the height of a spoke. In another embodiment, the bead filler 910 may have a height equal to 80-100% of the height of a spoke.
The bead filler 910 may control the rotation of the elongated member 140 with respect to reinforcement layer 150 as well as with respect to attachment points on a rim. Changing the length and other dimensions of the bead filler would affect such rotation.
Additionally, the bead filler 910 may affect how the spokes deflect during compression. The material and the dimensions of the bead filler may be selected to control the amount and the direction of such deflections.
In the illustrated embodiment, the embedding material 1000 is shown as having a consistent thickness along the entire spoke. In one embodiment, the embedding material 1000 is constructed of a single material. The embedding material 1000 may be constructed of a polymeric material, such as natural or synthetic rubber, or other elastomeric material. Alternatively, the embedding material 1000 may be constructed of a harder polymeric material such as polyurethane, polyester, nylon, or polyvinyl chloride (PVC). Alternatively, the embedding material may be one or more resins.
In an alternative embodiment, the embedding material 1000 may be formed of different materials in different regions of the tire. In another alternative embodiment, different regions of the tire may have multiple embedding materials of different materials.
The tire may be cured or otherwise heated, so that the embedding material 1000 softens. During such a process, the reinforcement layer 150 may become embedded into the embedding material 1000. Thus, the final tire may not have two distinct layers.
In the illustrated embodiment, the embedding material 1010 is shown as having a variable thickness. Here, the left side of the spoke is shown as having a thicker embedding material than the right side of the spoke. It should be understood, however, that this illustration is merely exemplary. The thickness of the embedding material 1010 may be varied at any point along the tire.
In one embodiment, the embedding material 1010 is constructed of a single material. The embedding material 1010 may be constructed of a polymeric material, such as natural or synthetic rubber, or other elastomeric material. Alternatively, the embedding material 1010 may be constructed of a harder polymeric material such as polyurethane, polyester, nylon, or polyvinyl chloride (PVC). Alternatively, the embedding material may be one or more resins.
In an alternative embodiment, the embedding material 1010 may be formed of different materials in different regions of the tire. In another alternative embodiment, different regions of the tire may have multiple embedding materials of different materials.
The tire may be cured or otherwise heated, so that the embedding material 1010 softens. During such a process, the reinforcement layer 150 may become embedded into the embedding material 1010. Thus, the final tire may not have two distinct layers.
The mechanical interaction between the elongated members and attachment points at a rim may be selected to achieve different performances. In some embodiments, it may be desirable for the elongated members to be fixed with respect to the rim attachment points. In other embodiments, it may be desirable for the elongated member to rotate with respect to the rim attachment points, without translating. In still other embodiments, it may be desirable for the elongated member to translate with respect to the rim attachment points, without rotating. In such an embodiment, the inner diameter of the tire effectively changes during operation, as the elongated member moves with respect to the rim. In still other embodiments, it may be desirable for the elongated member to rotate and translate with respect to the rim attachment points.
In one embodiment, the slot and the elongated member each have an irregular geometry to limit rotation. For example, the elongated member may have a protrusion that forms a stopper.
In an alternative embodiment, the rim 1100 includes a plurality of axially extending slots (not shown) instead of a circumferential groove. Each slot is configured to receive a portion of one of the plurality of elongated members 140. In this embodiment, the plurality of slots and the plurality of apertures 1110 together define a plurality of mounts, with each mount being configured to receive the elongated member 140 of a corresponding spoke 130.
In each of the described embodiments, the aperture 1110 is a circular aperture having a diameter slightly larger than the diameter of the elongated member 140. The fasteners are attached in a manner that allows the elongated member 140 to rotate within the circular aperture 1110. The fasteners prevent axial translation of the elongated member and the circular aperture 1110 prevents radial or circumferential translation of the elongated member 140.
In each of the described embodiments, the aperture 1210 is a slot extending in a radial direction and sized slightly larger than the diameter of the elongated member 140. The fasteners are attached in a manner that allows the elongated member 140 to rotate within the slot 1210, while the fasteners prevent axial translation of the elongated member 140. The slot allows for radial translation, but prevents circumferential translation of the elongated member 140. In other words, the elongated member 140 is free to rotate and free to translate in a radial direction.
In one embodiment, the slot may define two or more distinct attachment points. A camming feature may be employed to move the elongated member between pre-defined attachment points, rather than float to any position within the slot. In one such embodiment, the tire and rim assembly is a static system while in use. The user would adjust the cams between the pre-defined attachment points while the tire was not in use, and lock the cams into place. The attachment points would thus be fixed during use. In another such embodiment, the tire and rim assembly is a dynamic system while in use. An electrical, mechanical, or computer system would adjust the cams between the pre-defined attachment points during use of the tire.
In another embodiment, the rim attachment point is a slot and the elongated member is mounted to a spring, a gasket, or other flexible member. Thus, the elongated member may float within the slot in a controlled manner. The stiffness of the spring, gasket, or flexible member may be selected to optimize movement within the slot.
In another alternative embodiment, the elongated member is a hollow rod that is attached to a rim by a bearing rod. The bearing rod will allow the bottom of the spoke to rotate freely as the tire rotates.
In each of the above-described embodiments, the spokes 130 may be removeably mounted to the rim mounts. The use of fasteners such as nuts, clips, or pins allows the spokes to be easily removed from the rim. In an alternative embodiment, the spokes may be permanently attached to a rim.
To the extent that the term “includes” or “including” is used in the specification or the claims, it is intended to be inclusive in a manner similar to the term “comprising” as that term is interpreted when employed as a transitional word in a claim. Furthermore, to the extent that the term “or” is employed (e.g., A or B) it is intended to mean “A or B or both.” When the applicants intend to indicate “only A or B but not both” then the term “only A or B but not both” will be employed. Thus, use of the term “or” herein is the inclusive, and not the exclusive use. See, Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). Also, to the extent that the terms “in” or “into” are used in the specification or the claims, it is intended to additionally mean “on” or “onto.” Furthermore, to the extent the term “connect” is used in the specification or claims, it is intended to mean not only “directly connected to,” but also “indirectly connected to” such as connected through another component or components.
While the present application has been illustrated by the description of embodiments thereof, and while the 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 detail. Additional advantages and modifications will readily appear to those skilled in the art. Therefore, the application, in its broader aspects, is not limited to the specific details, the representative apparatus and method, and illustrative 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.
Filing Document | Filing Date | Country | Kind |
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PCT/US2022/077492 | 10/4/2022 | WO |
Number | Date | Country | |
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63254671 | Oct 2021 | US |