Mounting arrangement for self-supporting spoke structure of non-pneumatic tire

Abstract

A non-pneumatic tire includes a lower ring having a first diameter and an upper ring having a second diameter. The upper ring is substantially coaxial with the lower ring. A support structure connects the lower ring to the upper ring. The supporting structure is composed of a plurality of spokes. The support structure is arranged and configured such that adjacent spokes of the plurality of spokes contact each other upon occurrence of a high impact event.

Description

Technical Field

[0001] The present disclosure relates to a non-pneumatic tire. More specifically, the present disclosure relates to a non-pneumatic tire having a support structure with spokes designed to contact each other during a high impact event. Background Art

[0002] Various tire constructions have been developed that enable the tire to be driven in an uninflated or underinflated state. Non-pneumatic tires do not require inflation, while "run-flat tires" can continue to be driven at relatively high speeds for extended periods of time after being punctured and partially or completely decompressed. Non-pneumatic tires may include support structure, such as spokes or webs, connecting a lower ring to an upper ring. In some non-pneumatic tires, a circumferential tread may be attached to the upper ring of the tire.

[0003] The circumferential tread may include a tread band. The tread band may be a single layer of material or a multi-layer band. Such a tread band may also be referred to as a shear band, a shear element, or a thin, annular high-strength band element. When used in a non-pneumatic tire or in a pneumatic tire in a partially pressurized or unpressurized state, the shear element acts as a structural compression member. When used in a fully pressurized pneumatic tire, the shear element acts as a tension member.

[0004] Tire design for both pneumatic and non-pneumatic tires involves a balance of many factors, including but not limited to load capacity, handling, and ride quality. Regardless of the balance chosen between these factors, non-pneumatic tires must be durable and able to withstand high impact events, such as hitting curbs, potholes or other obstacles or road imperfections. Summary of the invention

[0005] In one embodiment, a non-pneumatic tire includes a lower ring having a first diameter and an upper ring having a second diameter. The upper ring is substantially coaxial with the lower ring. A support structure connects the lower ring to the upper ring. The support structure is composed of a plurality of spokes. The plurality of spokes are arranged into a first spoke group and a second spoke group axially spaced from the first spoke group. Each spoke of the plurality of spokes includes a first end connected to the lower ring, a second end connected to the upper ring, and a protective cover at the first end. The protective cover has a bottom plate portion. The bottom plate portion is attached to the lower ring to connect the first end of the spoke to the lower ring.

[0006] In another embodiment, a method for manufacturing a non-pneumatic tire includes providing a lower ring having a first diameter and an upper ring having a second diameter greater than the first diameter. A plurality of scalloped notches are formed on the lower ring. Each of the plurality of scalloped notches has a first curved surface. A plurality of spokes are formed. Each spoke extends between a first end and a second end. A plurality of protective shields are formed. Each of the plurality of protective shields has a second curved surface. A plurality of protective shields are attached to a corresponding one of the plurality of spokes at the first end. The plurality of spokes are arranged into a first spoke group and a second spoke group axially spaced apart from the first spoke group. The method also includes connecting the lower ring to the upper ring using the first spoke group and the second spoke group. The step of connecting the lower ring to the upper ring includes: attaching the second curved surface of the protective shield to the first curved surface of a scalloped notch in the plurality of scalloped notches to connect the first end of the spoke to the lower ring; and connecting the second end of the spoke to the upper ring.

[0007] In yet another embodiment, a non-pneumatic tire includes a lower ring having a first radius of curvature. The lower ring is provided with a plurality of scalloped notches. Each scalloped notch has a first curved surface having a second radius of curvature. An upper ring is coaxial with the lower ring. A support structure connects the lower ring to the upper ring. The support structure is composed of a plurality of spokes. Each spoke extends between a first end and a second end. A protective cover is provided at the first end. The protective cover has a third radius of curvature. Each of the first radius of curvature and the second radius of curvature is different from the third radius of curvature. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] In the accompanying drawings, structures are shown which, together with the detailed description provided below, describe exemplary embodiments of the invention protected by the claims. Similar elements are indicated by 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 drawn to scale, and for illustrative purposes, the proportions of certain elements may be exaggerated.

[0009] Figure 1 is a side view of one embodiment of a non-pneumatic tire,

[0010] Figure 2 yes Figure 1 Another side view of a non-pneumatic tire,

[0011] Figure 3 yes Figure 1 The cross-sectional view along 3-3,

[0012] Figure 4 yes Figure 1 A detailed view of area A,

[0013] Figure 5 yes Figure 1Detail of region A of FIG. 1 with some features removed for clarity.

[0014] Figure 6 yes Figure 1 Detail of a single spoke used in a non-pneumatic tire.

[0015] Figure 7 When the tire is on a flat surface and carrying a normal load Figure 1 a side view of a portion of a non-pneumatic tire,

[0016] Figure 8 When the tire is on a flat surface and carrying a normal load Figure 1 A side view of a portion of a non-pneumatic tire with some features removed for clarity.

[0017] Fig. 9 When the tire is on an uneven surface Figure 1 a side view of a portion of a non-pneumatic tire,

[0018] Fig.10 When the tire is on an uneven surface Figure 1 A side view of a portion of a non-pneumatic tire with some features removed for clarity.

[0019] Fig.11 It shows the manufacturing Figure 1 A flowchart of a method for a non-pneumatic tire,

[0020] Fig.12 is another embodiment of a spoke for a non-pneumatic tire,

[0021] Fig.12a yes Fig.12 End view of the spoke along II,

[0022] Fig.13 is a side view of a non-pneumatic tire showing the effects of manufacturing tolerances in the spokes before the second ends of the spokes are attached to the upper ring,

[0023] Fig.14 After the second end of the spoke is attached to the upper ring Fig.13 Side view of a non-pneumatic tire,

[0024] Fig.15 is a partial view of another embodiment of a non-pneumatic tire,

[0025] Fig.16 yes Fig.15 Detail of a single spoke used in a non-pneumatic tire.

[0026] Fig.17 yes Fig.15A cross-sectional view along 17-17,

[0027] Fig.18 is a partial view of another embodiment of a non-pneumatic tire,

[0028] Fig.19 is a perspective view of the end cap,

[0029] Fig. 20 is a partial side view of another embodiment of a non-pneumatic tire,

[0030] Fig.21 yes Fig. 20 a partial perspective view of a non-pneumatic tire, and

[0031] Fig. 22 yes Fig. 20 Another partial perspective view of a non-pneumatic tire. DETAILED DESCRIPTION

[0032] The following includes definitions of selected terms used herein. These definitions include various examples or forms of components that fall within the scope of the term and can be used for implementation. The examples are not intended to be limiting. Both singular and plural forms of the terms may be within the definitions.

[0033] "Axial" and "axially" refer to directions parallel to the tire's axis of rotation.

[0034] “Circumferential” and “circumferentially” refer to directions perpendicular to the axial direction extending along the circumference of the surface of the tread.

[0035] "Radial" and "radially" refer to directions perpendicular to the tire's axis of rotation.

[0036] As used herein, "tread" means that portion of the tire that comes into contact with the road or ground under normally inflated and normally loaded conditions.

[0037] Although similar terms are used in the following description to describe common tire components, it should be understood that because these terms carry slightly different meanings, one of ordinary skill in the art would not consider any of the following terms to be completely interchangeable with another term used to describe common tire components.

[0038] Directions are set forth herein with reference to the axis of rotation of the tire. The terms "upwardly" and "upwardly" refer to a general direction toward the tread of the tire, while "downwardly" and "downwardly" refer to a general direction toward the axis of rotation of the tire. Thus, when relative directional terms such as "upper" and "lower" or "top" and "bottom" are used in conjunction with an element, the "upper" or "top" element is spatially closer to the tread than the "lower" or "bottom" element. Additionally, when relative directional terms such as "above" or "below" are used in conjunction with an element, if an element is "above" another element, it means that the element is closer to the tread than the other element.

[0039] The terms "inwardly" and "inwardly" refer to general directions toward the equatorial plane of the tire, while "outwardly" and "outwardly" refer to general directions away from the equatorial plane of the tire and toward the sides of the tire. Thus, when relative directional terms such as "inner" and "outer" are used in conjunction with an element, the "inner" element is spatially closer to the equatorial plane of the tire than the "outer" element.

[0040] Figures 1 to 5 One embodiment of a non-pneumatic tire 10 is shown. The non-pneumatic tire 10 is shown for exemplary purposes only and is not intended to be limiting. In the illustrated embodiment, the non-pneumatic tire 10 includes a generally annular lower ring 20. The lower ring 20 can engage a vehicle wheel hub (not shown) to attach the tire 10 to the vehicle. The lower ring 20 has an inner surface 23 and an outer surface 24, and can be made of a polymeric material, an elastomeric material, a metal, a composite composed of a polymer reinforced with glass or carbon fiber, or any other desired material or combination of materials.

[0041] The non-pneumatic tire 10 also includes a generally annular upper ring 30. The upper ring 30 has a diameter greater than the diameter of the lower ring 20 and is substantially coaxial with the lower ring 20. The upper ring 30 has an inner surface 33 and an outer surface 34, and may be made of a polymeric material, an elastomeric material, a metal, a composite composed of a polymer reinforced with glass or carbon fiber, or any other desired material or combination of materials. A circumferential tread 70 is attached to the outer surface 34 of the upper ring 30. The circumferential tread 70 may be attached to the upper ring 30 adhesively, mechanically, or by any other desired arrangement.

[0042] like Figure 3 As shown, the circumferential tread 70 includes a tread band 72 and a tread layer 74. The tread band 72 and the tread layer 74 may be made of the same material or different materials. The tread layer 74 may be made of rubber and may include tread elements (not shown), such as grooves, ribs, blocks, lugs, sipes, posts, or any other desired tread elements. The tread band may include a filament assembly.

[0043] In the illustrated embodiment, the tread band 72 is shown as a single layer. In an alternative embodiment, the tread band can be a multi-layer band. Such a multi-layer tread band may include one or more layers of substantially inextensible material. The layer may be formed by a sheet of material, a rope of material, a thread of material, or any other desired arrangement. In other alternative embodiments, the multi-layer tread band may include a layer of extensible material, such as an elastomer. According to an example embodiment, the tread band may include a pair of inextensible layers separated by a layer of extensible material. In other alternative embodiments, the tread band may include a band known as a shear band, a shear element, or a thin annular high-strength belt element.

[0044] The support structure 100 connects the lower ring 20 to the upper ring 30. The support structure 100 extends from the outer surface 24 of the lower ring 20 and the inner surface 33 of the upper ring 30. The support structure 100 is composed of a plurality of spokes 200. In the illustrated embodiment, the plurality of spokes 200 are arranged into two axially spaced spoke sets, including a first spoke set 202 and a second spoke set 204 axially spaced from the first spoke set 202. In alternative embodiments, the support structure may include more than two axially spaced spoke sets.

[0045] like Figure 3 As shown, the first spoke group 202 and the second spoke group 204 are spaced apart from each other in the axial direction. In alternative embodiments, the space between the first spoke group and the second spoke group can be larger or smaller, or the first spoke group and the second spoke group can be arranged with no space between them. Figure 1 Each spoke 200 of the first spoke set 202 is substantially convex relative to the clockwise circumferential direction of the non-pneumatic tire 10 and each spoke of the second spoke set 204 is substantially concave relative to the clockwise circumferential direction of the non-pneumatic tire 10 when viewed at the angle shown.

[0046] All spokes 200 of the first spoke group 202 and the second spoke group 204 have the same configuration. Therefore, the description of the spokes 200 will refer to Figure 6 The spoke 200 is made of a single spoke 200 shown in FIG. The spoke 200 may be made of a metal such as steel or aluminum, a polymer such as polyester or nylon, a composite such as a glass fiber or carbon fiber reinforced polymer, or any other desired material or material combination. The spoke 200 may be provided with reinforcements (not shown).

[0047] The spoke 200 extends between a first end 206 and a second end 208 and has a generally rectangular cross-section including a first surface 210 and a second surface 212 facing opposite the first surface 210. The spoke thickness t refers to the distance between the first surface 210 and the second surface 212. In the illustrated embodiment, the spoke 200 has a constant thickness between the first end 206 and the second end 208. In alternative embodiments, the thickness of the spoke may vary between the first end and the second end. For example, the spoke may have a relatively thick portion at the first end and the second end, and a relatively thin portion between the ends. In other alternative embodiments, the spoke may have any desired cross-sectional shape (e.g., circular, diamond, hexagonal, etc.) or may have a combination of different cross-sectional shapes.

[0048] An integral foot 214 is provided toward the first end 206 of the spoke 200. The first surface 210 of the spoke 200 is attached to the outer surface 24 of the lower ring 20 at the foot 214 to connect the first end 206 of the spoke 200 to the lower ring 20. The foot 214 can be attached to the outer surface 24 of the lower ring 20 using welding, brazing, soldering, adhesives, mechanical fasteners (e.g., bolts, rivets), keys / keyways, or any other desired arrangement. In the illustrated embodiment, the foot 214 is substantially straight and the entire length (the dimension of the foot extending in the circumferential direction of the tire) and the entire width (the dimension of the foot extending in the axial direction of the tire) are fixed to the outer surface 24 of the lower ring 20. In alternative embodiments, the foot can be a separate component attached to the spoke. In other alternative embodiments, the foot can be curved to match the radius of curvature of the outer surface of the lower ring or have any other desired curvature. In further alternative embodiments, only a portion or multiple discrete portions of the foot can be attached to the outer surface of the lower ring. In other alternative embodiments, the feet may be attached below the outer surface of the lower ring, or the spokes may extend through the lower ring so that the feet may be attached to the inner surface of the lower ring.

[0049] The flex member 216 is disposed at the second end 208 of the spoke 200. The flex member 216 has a width extending in the axial direction of the tire. The flex member 216 may be made of a polymer (e.g., polyurethane or rubber), a thin curved metal piece, or any other desired material or material combination. In the illustrated embodiment, the flex member 216 is configured as a cuboid and is arranged so that the end of the flex member 216 is aligned with the second end 208 of the spoke 200. In other alternative embodiments, the flex member may be arranged so that the end of the flex member is retracted relative to the second end of the spoke, or may be arranged so that the end of the flex member extends beyond the second end of the spoke. In other alternative embodiments, the flex member may be replaced by a mechanical pin joint (i.e., a hinge).

[0050] The flex member 216 includes a spoke-facing surface 218 and a ring-facing surface 220. The spoke-facing surface 218 of the flex member 216 is attached to the second surface 212 of the spoke 200, and the ring-facing surface 220 is attached to the inner surface 33 of the upper ring 30 to connect the second end 208 of the spoke 200 to the upper ring 30. The attachment between the flex member 216 and the spoke 200 or between the flex member 216 and the upper ring 30 can be achieved using welding, brazing, soldering, adhesives, mechanical fasteners (e.g., bolts, rivets), keys / keyways, or any other desired arrangement. For example, the attachment can be provided by pouring polyurethane directly onto the spoke, with or without first coating the spoke with a primer.

[0051] The flex members 216 provide flexibility to the connection between the second ends 208 of the spokes 200 and the upper ring 30. This flexibility reduces the likelihood of high stresses being generated within the spokes 200, thereby increasing the robustness of the non-pneumatic tire 10. The connection provided by the feet 214 at the first ends 206 of the spokes 200 is more rigid than the flexible connection provided by the flex members 216.

[0052] In alternative embodiments, the flexure members may have shapes or configurations that are different than those specifically shown and described. In other alternative embodiments, additional structures or mechanisms may supplement the flexure members to attach the second ends of the spokes to the upper ring. In further alternative embodiments, the flexure members may be omitted and the second ends of the spokes may be directly attached to the upper ring. In these alternative embodiments, the second ends of the spokes may be directly attached to the inner surface of the upper ring, above the inner surface of the upper ring, or the spokes may extend through the upper ring so that the second ends may be attached to the outer surface of the upper ring.

[0053] The spoke 200 includes a toggle portion 222 located between the first end 206 and the second end 208. The toggle portion 222 has a first radius of curvature r1. According to an exemplary embodiment, the first radius of curvature r1 is 2 inches to 6 inches (5 cm to 15 cm). When attached to the upper ring 20 and the lower ring 30, the toggle portion 222 is concavely curved relative to the lower ring 20.

[0054] The transition portion 224 is disposed between the toggle portion 222 and the first end 206. The transition portion 224 has a second radius of curvature r2. According to an exemplary embodiment, the second radius of curvature r2 is 0 inches to 2 inches (0 cm to 5 cm). When attached to the upper ring 20 and the lower ring 30, the transition portion 224 is convexly curved relative to the lower ring 20. Therefore, relative to the single spoke 200, the toggle portion 222 and the transition portion 224 are concavely curved in opposite facing directions. In an alternative embodiment, the toggle portion and the transition portion are concavely (or convexly) curved in the same direction.

[0055] The foot 214 extends from the transition portion 224 to the first end 206 of the spoke 200. The first connecting portion 226 connects the transition portion 224 to the toggle portion 222, and the second connecting portion 228 connects the toggle portion 222 to the second end 208 of the spoke 200. In the illustrated embodiment, the first connecting portion 226 and the second connecting portion 228 are both linear. In alternative embodiments, the first connecting portion or the second connecting portion may be curved or have any other desired configuration. In other alternative embodiments, the transition portion and the foot may be omitted. In such alternative embodiments, the first end of the spoke will be located at the end of the first connecting portion.

[0056] The base plane p1 intersects the transition portion 224 and the second end 208 of the spoke 200 and serves as a reference for various dimensional aspects of the spoke 200. The angle between the base plane p1 and the second plane p2 extending tangentially to the outer surface 24 of the lower ring 20 at the transition portion 224 is α. According to an exemplary embodiment, the angle α is 5 to 20 degrees. The distance between the transition portion 224 and the second end 208 of the spoke 200 along a direction parallel to the base plane p1 is d1. According to an exemplary embodiment, the distance d1 is 10 inches to 15 inches (25 cm to 38 cm). Along the direction parallel to the base plane p1, the distance between the center of the transition portion 224 and the center of the first radius of curvature r1 of the elbow portion 222 is d2. According to an exemplary embodiment, the value of the distance d2 is 40% to 70% of the distance d1. The maximum distance between the elbow portion 222 and the base plane p1 along a direction perpendicular to the base plane p1 is d3. According to one example embodiment, distance d3 is 2 inches to 4 inches (5 cm to 10 cm).

[0057] Reference Fig.10 The transition portion 224 of one spoke 200 is separated from the first end 206 of an adjacent spoke 200 by a first spacing distance s1. The second ends 208 of adjacent spokes 200 are separated from each other by a second spacing distance s2.

[0058] A non-pneumatic tire constructed according to the above-described design parameters may provide a more robust assembly, particularly in terms of impact performance. Figure 7 and Figure 8 A tire is shown in an exemplary first condition. Figure 7 and Figure 8 As shown, according to a non-limiting example, in a first condition, the tire 10 is rolling on a flat surface while bearing a load (i.e., normal operation), the non-pneumatic tire 10 is deformed, but adjacent spokes 200 do not contact each other. The lack of contact between adjacent spokes 200 during normal operation is desirable to avoid generating unnecessary stress in the structure of the non-pneumatic tire 10.

[0059] It is expected that the non-pneumatic tire 10 will be exposed to high impact events during its life, such as striking a curb, pothole or other obstacle or road defect. During a high impact event, the non-pneumatic tire 10 may deform at a significantly higher level than that which occurs during normal operation.

[0060] Fig. 9 and Fig.10 1 shows a tire in an exemplary second condition, the second condition being different from the first condition. Fig. 9 and Fig.10 As shown, according to a non-limiting example, in a second condition, the non-pneumatic tire 10 experiences a high impact event in which the tire rolls on an uneven surface. According to one non-limiting example, the uneven surface is a road defect that protrudes above the ground or is pressed into the ground by a distance of 3 inches (8 cm). According to another non-limiting example, the uneven surface is a road defect that protrudes above the ground or is pressed into the ground by a distance of 4.5 inches (11 cm). According to yet another non-limiting example, the uneven surface is a road defect that protrudes above the ground or is pressed into the ground by a distance of 6 inches (15 cm).

[0061] The non-pneumatic tire 10 responds to a high impact event by deforming so that adjacent spokes 200 contact one another. It has been surprisingly discovered that the contact between adjacent spokes 200 during a high impact event significantly reduces the stress experienced by each spoke 200, as compared to a non-pneumatic tire where the spokes do not contact one another during the high impact event. The reduction in stress in each spoke 200 is a result of the contact between adjacent spokes 200 because the contact distributes the load among the plurality of spokes 200. In other words, rather than a single spoke 200 absorbing the load generated by a high impact event, the plurality of spokes 200 share the same load, thereby reducing the peak load of any one single spoke 200.

[0062] In the illustrated embodiment, the non-pneumatic tire 10 is arranged and configured so that at least three adjacent spokes 200 are in contact with each other simultaneously during a high impact event, and the spokes 200 in contact with each other are located adjacent to the obstacle or road defect that caused the high impact event. In alternative embodiments, the non-pneumatic tire may be arranged and configured to have a lesser or greater number of adjacent spokes in contact with each other simultaneously during a high impact event. In other alternative embodiments, the adjacent spokes in contact with each other simultaneously may be located at any position along the circumferential direction of the tire (i.e., spaced apart from the obstacle or road defect that caused the high impact event).

[0063] Design parameters of the spokes 200 and other components of the non-pneumatic tire 10 may be varied to provide desired performance characteristics to the non-pneumatic tire 10. Preferably, these design parameters are selected so that contact between adjacent spokes 200 occurs before the spokes 200 begin to yield or experience any other form of damage.

[0064] The maximum distance d3 between the toggle portion 222 and the base plane p1 in a direction perpendicular to the base plane p1 affects the spoke stiffness and when contact between adjacent spokes 200 will occur. Increasing the distance d3 will physically move each spoke 200 closer to the adjacent spoke 200, thus causing contact between adjacent spokes 200 to occur relatively sooner. In addition, increasing the distance d3 will reduce the stiffness of the spokes 200, thereby increasing the amount of deflection for a given load, which increases the likelihood of contact between adjacent spokes 200. Reducing the distance d3 will have the opposite effect and will physically move each spoke 200 away from the adjacent spoke 200, thus causing contact between adjacent spokes 200 to occur relatively later. In addition, reducing the distance d3 will increase the stiffness of the spokes 200, thus reducing the amount of deflection for a given load, which reduces the likelihood of contact between adjacent spokes 200.

[0065] The distance d2 between the transition portion 224 and the center of the first radius of curvature r1 of the toggle portion 222 in a direction parallel to the base plane p1 affects when contact will occur with the adjacent spokes 200. When the distance d2 is a larger percentage of d1, this will cause contact between adjacent spokes 200 to occur relatively quickly. When the distance d2 is a smaller percentage of d1, this will cause contact between adjacent spokes 200 to occur relatively late.

[0066] The radius of curvature r1 of the toggle portion 222 affects when contact with adjacent spokes 200 will occur. Reducing the radius of curvature r1 will cause contact between adjacent spokes 200 to occur relatively late, while increasing the radius of curvature r1 will cause contact between adjacent spokes 200 to occur relatively soon. The spoke thickness t affects the stiffness of the spoke 200. Increasing the spoke thickness t will increase the stiffness of the spoke 200, while reducing the spoke thickness will reduce the stiffness of the spoke 200.

[0067] In addition, it has been found that the vertical stiffness of the tire is affected by the combination of the spoke thickness t and the distance d3. Increasing the distance d3 reduces the tire stiffness, while reducing the distance d3 increases the tire stiffness. Therefore, it has been found that in order to meet the target value of tire stiffness, spokes with a larger thickness t should be combined with a larger distance d3, while spokes with a smaller thickness t should be combined with a smaller distance d3.

[0068] Fig.1110 is a flow chart illustrating an exemplary method of manufacturing a non-pneumatic tire. At 1010, a lower ring and an upper ring are provided. The lower ring has a first diameter, and the upper ring has a second diameter greater than the first diameter. At 1020, a plurality of spokes are formed. The spokes may be formed using hot stamping, cold forming, extrusion, rolling, bending, or any other desired method. In addition, the spokes may be formed using a variety of composite manufacturing techniques (e.g., high pressure resin transfer molding). Each spoke extends between a first end and a second end. A toggle portion is located between the first end and the second end, and a transition portion is located between the first end and the toggle portion. The toggle portion and the transition portion are concavely curved in opposite facing directions. A foot extends from the transition portion.

[0069] At 1030, a flex member is attached to the spokes. At 1040, the spokes are arranged into a first spoke set and a second spoke set axially spaced from the first spoke set. Additionally, a plurality of spokes of the first spoke set are arranged to be concavely curved relative to a first circumferential direction of the tire, and a plurality of spokes of the second spoke set are arranged to be convexly curved relative to the first circumferential direction of the tire.

[0070] At 1040, the lower ring is connected to the upper ring using the first spoke group and the second spoke group. The foot of each spoke is attached to the lower ring to connect the first end of each spoke to the lower ring. The flex member is attached to the upper ring to connect the second end of each spoke to the upper ring.

[0071] In alternative embodiments, the aforementioned steps may occur in an order different from that specifically described. In other alternative embodiments, the method may include a greater or lesser number of steps.

[0072] Fig.12 and Fig.12a Another embodiment of a spoke 1200 is shown. Fig.12 and Fig.12a The spokes of 1200 with Figures 1 to 10 The spokes 200 in FIG. 1 are substantially identical except for the differences described herein. Therefore, similar features will be identified by similar numbers increased by a factor of "1000". Figures 1 to 10 In the illustrated spoke 200, the second connecting portion 228 is linear. In contrast, Fig.12 and Fig.12a The spoke 1200 has a curved second connecting portion 1228 with a radius of curvature r3. Compared with the linear second connecting portion, Fig.12 and Fig.12a The curved second connecting portion 1228 in the spoke 1200 significantly enhances the self-supporting behavior. According to an exemplary embodiment, the radius of curvature r3 is 10 inches to 50 inches (25 cm to 127 cm).

[0073] In addition to the above Figures 1 to 10In addition to the design parameters and resulting changes in performance characteristics discussed in the illustrated spoke 200, Fig.12 and Fig.12a The radius of curvature r3 of the curved second connection portion 1228 in the spoke 1200 can be varied to affect performance. The radius of curvature r3 of the curved second connection portion 1228 and the width w of the flexure member 1216 挠曲 The second connection portion 1228 is a curved second connection portion 1228 that is formed by a plurality of curved surfaces 1224 and 1225. The curved ... curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1228. The curved second connection portion 1228 is a curved second connection portion 1228 that is curved second connection portion 1

[0074] The width w of the flexure member 1216 挠曲 The radius of curvature r3 affects its ability to apply torque at the ends of the spokes 1200. This torque acts to straighten the curved second connecting portion 1228 when the tire is rolling under normal load or subjected to a high impact event. Therefore, it has been found that a curved second connecting portion 1228 with a smaller radius of curvature r3 is more effective than a curved second connecting portion 1228 with a larger width w 挠曲 The flexure member 1216 of the embodiment of the present invention is optimally matched, while the curved second connecting portion 1228 having a larger radius of curvature r3 is optimally matched with the curved second connecting portion 1228 having a smaller width w 挠曲 In addition to the width w of the flexure member 1216, 挠曲 In addition, the ability of the flexure members 1216 to apply torque on the spokes 1200 is also affected by the stiffness of the material used to make the flexure members 1216. Therefore, when using a softer material, it is desirable to provide a flexure member having a wider width w 挠曲 flexure member 1216, and when using a harder material, it is desirable to provide a flexure member 1216 having a narrower width w 挠曲 Flexure member 1216.

[0075] The non-pneumatic tire described herein improves the robustness of the non-pneumatic tire by providing an arrangement in which adjacent spokes contact each other during a high impact event. The contact between adjacent spokes results in multiple spokes sharing the load, thereby significantly reducing the stress experienced by any single spoke in the non-pneumatic tire. Thus, the durability of the non-pneumatic tire is improved.

[0076] In the above-described embodiment, the foot 214 of the spoke 200 is initially substantially straight and is bonded to the curved outer surface 24 of the lower ring 20. The bonding process forces the foot 214 to adapt to the curvature of the outer surface 24. Although this arrangement results in a relatively simple manufacturing process for the spoke 200 and the lower ring 20, it may create other potential design difficulties. For example, in the flat foot embodiment, the primary applied force acting on the joint between the spoke and the ring is tension. This tension may result in a cracking type failure at the leading edge of the spoke. For another example, the rotational position of each spoke relative to the lower and upper rings cannot be adjusted without undesirably introducing prestress into the spokes.

[0077] Rotational adjustment of the spoke may be necessary to take into account manufacturing tolerances. Ideally, each spoke of a non-pneumatic tire would be identical, including the dimensions of the various elements (e.g., the lengths of the foot, the first connecting portion, and the second connecting portion) and the angles between these elements (e.g., the angle between the foot and the first connecting portion or between the first connecting portion and the second connecting portion). However, in practice, it is unlikely that each spoke will be identical. The manufacturing guidelines recognize variations in the formed features of the product, such as material thickness and temper tolerances. In addition, these manufacturing guidelines recognize variations in bend angle tolerances, with one guideline suggesting a tolerance of + / - one degree.

[0078] Fig.13 and Fig.14 shows how this + / - one degree tolerance can affect the support structure of a non-pneumatic tire. Figures 1 to 6 Non-pneumatic tire implementation scheme structure Fig.13 and Fig.14 Therefore, similar features will be indicated by similar reference numerals.

[0079] Fig.13 and Fig.14 The first spoke 200a, the second spoke 200b and the third spoke 200c are shown. In the first spoke 200a and the third spoke 200c, the angle θ between the foot 214 and the first connecting portion 226 is 1 degree smaller than the specified design value, while in the second spoke 200b, the angle θ is 1 degree larger than the design value. Fig.13 The spokes 200 are shown when the feet 214 are connected to the lower ring 20 and the second end 208 of each spoke 200 is in a natural or resting position (i.e., the position of the second ends 208 of the spokes 200 without any external forces applied and before the flex members 216 are attached to the upper ring 30). Fig.14 The spoke 200 is shown after the second end 208 of the spoke 200 has been moved to the desired position and the flex member 216 is attached to the upper ring 30. Fig.13As shown, making the angle between the foot 214 and the first connecting portion 226 out of specification by one degree can cause various problems, including causing the flexure member 216 to naturally rest above the upper ring 30 (second spoke 200b) or below the upper ring 30 (first 200a and third spoke 200c), and having irregular spacing between adjacent spokes 200. Some of these problems can be corrected by forcing the second end 208 of each spoke 200 into a desired position, such as Fig.14 As shown, this undesirably introduces prestress into the spokes 200. In theory, each spoke 200 can be rotated about its first end 206 to correct these problems. However, in practice, due to the geometry between the flat foot 214 and the outer surface of the lower ring 20, such rotation is not possible.

[0080] Fig.15 A portion of an alternative embodiment of a non-pneumatic tire is shown having features that alleviate the above-mentioned issues regarding manufacturing tolerances. Fig.16 and Fig.17 Shows Fig.15 A single spoke of a non-pneumatic tire. Figures 15 to 17 The arrangement shown in is essentially similar to Figures 1 to 6 The arrangement shown in , except for the differences described herein. Therefore, like features will be identified by like numbers with the value "2000" increased.

[0081] The non-pneumatic tire 2010 includes a support structure 2100 connecting a lower ring 2020 to an upper ring (not shown). The support structure 2100 is composed of a plurality of spokes 2200 (only a single spoke is shown), which are arranged into a first spoke group and a second spoke group (not shown). The first spoke group and the second spoke group are offset and spaced apart from each other in the axial direction of the non-pneumatic tire 2010.

[0082] Each spoke 2200 extends between a first end 2206 and a second end 2208 and includes a first surface 2210 and a second surface 2212. A flex member 2216 is disposed at the second end 2208 of the spoke 2200. A toggle portion 2222 is disposed between the first end 2206 and the second end 2208. A first connecting portion 2226 connects the first end 2206 to the toggle portion 2222. A second connecting portion 2228 connects the toggle portion 2222 to the second end 2208 of the spoke 2200. Figures 1 to 6 The spokes shown in the embodiment are different, Figures 15 to 17 The spokes shown in the embodiment do not include a transition portion or foot.

[0083] The protective shield 2215 is attached to the first end 2206 of the spoke 2200. The protective shield 2215 can be made of steel, aluminum, titanium, magnesium, a composite material (e.g., aluminum metal matrix, carbon fiber, reinforced plastic), or any other desired material, and can be attached to the spoke 2200 using adhesives, mechanical fasteners, a combination of adhesives and mechanical fasteners, welding, or any other desired arrangement. The protective shield 2215 extends between the first edge 2327 and the second edge 2329. The distance between the first edge 2327 and the second edge 2329 defines the protective shield width. As used herein, "width" refers to the dimension of a component extending in the axial direction of the non-pneumatic tire 2010. In the illustrated embodiment, the width of the protective shield 2215, the width of the spoke 2200, and the width of the lower ring 2020 are all equal to each other. In alternative embodiments, the width of the protective shield, the spoke, and the lower ring can be increased or decreased so that the width of any one of these elements is greater or less than another of these elements.

[0084] The protective cover 2215 includes a first side 2217 and a second side 2219. The first side 2217 includes a first linear top plate portion 2221. The second side 2219 includes a second arcuate top plate portion 2227. The first top plate portion 2221 and the second top plate portion 2227 meet at a peak 2229. The spoke 2200 enters the protective cover 2215 through a hole 2231 provided on the second arcuate top plate portion 2227. The first wall portion 2233 extends from the first top plate portion 2221 at an obtuse angle, and the second wall portion 2235 extends from the second top plate portion 2221 at an obtuse angle. The first wall portion 2233 and the second wall portion 2235 are both linear and extend parallel to each other. The bottom plate portion 2237 extends between the first wall portion 2233 and the second wall portion 2235. When the spoke 2200 is received in the boot 2215, the first end 2206 of the spoke 2200 is spaced apart from the bottom plate portion 2237. The boot 2215 can provide a more rigid attachment than an embodiment of the spoke without the boot. The design of the boot and the orientation of the spoke relative to the boot can be varied to provide desired performance characteristics for a non-pneumatic tire.

[0085] The outer surface 2024 of the lower ring 2020 is provided with a plurality of scalloped notches 2025, the number of which is equal to the total number of spokes 2200 in the support structure 2100. The bottom plate portion 2237 of the protective cover 2215 is curved and has a radius of curvature r equal to the corresponding scalloped notches 2025. s The radius of curvature r fp. The scalloped recesses 2025 are spaced apart from one another in the circumferential direction of the non-pneumatic tire 2010, and are arranged into a first scalloped recess group and a second scalloped recess group (not shown). Similar to the separation between the first spoke group and the second spoke group, the scalloped recess groups are also offset and spaced apart from one another in the axial direction of the non-pneumatic tire 2010. The bottom plate portion 2237 of the protective cover 2215 is coupled to the corresponding scalloped recesses 2025 to attach the first ends of the spokes 2200 to the lower ring 2020. The flex member 2216 is coupled to the upper ring 2030 to connect the second ends 2208 of the spokes 2200 to the upper ring 2030. In alternative embodiments, the protective cover or the flex member may be attached to the scalloped recesses or the upper ring, respectively, using any desired arrangement.

[0086] The above arrangement helps to solve potential design problems associated with flat foot spoke embodiments regarding spoke manufacturing tolerances. Providing a spoke 2200 having a protective cover 2215 with a curved floor portion 2237 and a corresponding curved scallop 2205 for a non-pneumatic tire 2010 causes the primary applied force on the joint between the protective cover 2215 and the lower ring 20 to be a shear force, rather than a tension force as in the flat floor portion embodiment. This change reduces the likelihood of a cracking type failure mode occurring at the connection between the spoke 2200 and the lower ring 2020. In addition, the shear force acting on the joint between the protective cover 2215 and the lower ring 2020 causes the joint to enter a significantly stronger failure mode for most commonly used adhesives.

[0087] In addition, the curved floor portion 2237 and scalloped recesses 2025 of the shield 2215 allow for adjustment of the rotational position of each spoke 2200 relative to the lower ring 2020 and upper ring 2030 without pre-introducing stress into the spoke as is the case with the flat foot embodiment. These curved surfaces also allow for a constant adhesive gap to be maintained between the shield 2215 and the scalloped recesses 2025 during such rotational position adjustment.

[0088] It has been found that the radius of curvature r of the bottom plate portion 2237 fp and the radius of curvature r of the sector notch 2025 s Certain design principles should be met in order to provide the above flexibility regarding rotational position adjustment. According to an exemplary design principle, the radius of curvature r at the bottom plate portion 2237 is fp and the radius of curvature r of the sector notch 2025 s Different from the curvature radius r of the outer surface 2024 of the lower ring 20 lr .

[0089] In the illustrated embodiment, the bottom plate portion 2237 of the protective cover 2215 and the scalloped recess 2025 are both convex relative to the inner surface 2023 of the lower ring 2020, and the curvature radius r of the bottom plate portion 2237 isfp and the radius of curvature r of the sector notch 2025 s are constant and equal to each other. In addition, the scalloped recesses 2025 are formed directly on the lower ring 2020. In an alternative embodiment, the floor portion of the protective cover may protrude relative to the inner surface of the spokes, and the lower ring may be provided with corresponding protrusions that also protrude relative to the inner surface of the spokes. In other alternative embodiments, the radius of curvature of the floor portion or the radius of curvature of the scalloped recesses or protrusions may be variable or different from each other. In a further alternative embodiment, the scalloped recesses or protrusions may be formed on a sleeve fixed to the outer surface of the lower ring.

[0090] In addition, it has been found that a protective cover without scallops can be used on the inner ring. In such an arrangement, the floor portion of the protective cover has a shape that is complementary to the shape of the outer surface of the lower ring. According to a non-limiting example where scallops are not used, the floor portion of the protective cover has a radius of curvature that is substantially the same as the radius of curvature of the outer surface of the lower ring. In addition, it has been found that the scallops on the lower ring can be other shapes besides curved. According to a non-limiting example, the scallops can be provided as a flat portion on the outer surface of the lower ring. In this arrangement, the floor portion of the protective cover will be flat so as to complement the flat portion on the lower ring.

[0091] Fig.18 A variation of a protective cover 3215 for a non-pneumatic tire is shown. Fig.18 The protective cover 3215 with Figures 15 to 17 The protective cover 2215 shown in the non-pneumatic tire 2010 is substantially the same, except for the differences described herein. Therefore, similar features will be identified by similar numbers increased by a factor of "1000".

[0092] The protective cover 3215 includes a first side 3217 and a second side 3219. The first side 3217 includes a first linear top plate portion 3221. The second side 3219 includes a second stepped top plate portion 3227. The first top plate portion 3221 and the second top plate portion 3227 meet at a peak 3229. The spokes 3200 enter the protective cover through holes 3231 provided on the second top plate portion 3227. The holes 3231 extend across the entire width of the protective cover 6548 and divide the second top plate portion 3227 into a first step 3227a and a second step 3227b. A linear wall portion 3235 extends from the second step 3227b at a substantially right angle. The wall portion 3235 extends substantially parallel to the first top plate portion 3221. A linear ceiling portion 3239 extends from the wall portion 3235 at an arc angle. The linear ceiling portion 3239 and the wall portion 3235 together define a substantially V-shaped recess. The bottom plate portion 3237 extends between the first top plate portion 3221 and the ceiling portion 3239. The curvature radius r of the bottom plate portion 3237 isfp is equal to the curvature radius r of the corresponding sector-shaped recess 3025 provided on the outer surface 3024 of the lower ring 3020 s .

[0093] The specific arrangement of the boot 3215 can allow the local stiffness of the boot 3215 to be adjusted to reduce the peak stress in the adhesive or other fastening arrangement. This reduction in peak stress can be provided by the V-shaped notch defined by the linear ceiling portion 3239 and the wall portion 3235. The design of the boot and the orientation of the spokes relative to the boot can be changed to provide certain desired performance characteristics for the non-pneumatic tire. For example, increasing the size of the V-shaped notch can reduce the stiffness of the boot, while reducing the size of the notch can increase the stiffness of the boot. As another example, changing the position of the spokes entering the boot can also change the stress in the boot and the adhesive or other fastening arrangement.

[0094] Fig.19 An end cap 5000 is shown that can be used with a spoke 5002 having a boot 5004. The end cap 5000 can be provided to limit adhesive "squeeze out" during the bonding process between the boot and the lower ring 5003. In addition, the end cap can act as a structural member to strengthen the boot 5004.

[0095] End cap 5000 may be made of metal, composite material, plastic, rubber, polymer, or any other desired material or combination of materials. End cap 5000 includes a boot mating surface 5006 and an exterior-facing surface 5008. Boot mating surface 5006 is attached to boot 5004 to secure end cap 5002 to boot 5004. Such attachment may be achieved using adhesives, mechanical fasteners, a combination of adhesives and mechanical fasteners, or any other desired fastening arrangement. Exterior-facing surface 5008 may be flat, or may be provided with functional features or decorative features (e.g., corporate logos).

[0096] The end cap 5000 includes a first top plate portion 5010 and a second top plate portion 5012 that meet at a peak 5014. A first wall portion 5016 extends from the first top plate portion 5010, and a second wall portion 5018 extends from the second top plate portion 5012. A bottom plate portion 5020 extends between the first wall portion 5016 and the second wall portion 5018. In the illustrated embodiment, the profile of the end cap 5000 is substantially the same as the profile of the protective cover 5004 to which the end cap 5000 is attached. In alternative embodiments, the end cap 5000 can have any desired profile (i.e., a profile that is different from the profile of the protective cover).

[0097] Figure 20 to Figure 22 Another embodiment of a protective cover 4215 for a non-pneumatic tire is shown. Protective cover 4215 is similar to Figures 15 to 17The protective cover 2215 is shown in the non-pneumatic tire 2010, except for the differences described herein. Therefore, similar features will be identified by similar numbers increased by a factor of "2000".

[0098] The protective cover 4215 includes a first portion 4217 and a second portion 4219. The first portion 4217 and the second portion 4219 are separate discrete components. The first portion 4217 and the second portion 4219 define a gap 4231 for receiving the spoke 4200. When so received, the spoke 4200 is sandwiched between the first portion 4217 and the second portion 4219.

[0099] The first portion 4217 includes a linear top plate portion 4221 and a bottom plate portion 4237. The curvature radius r of the bottom plate portion 4237 is fp is substantially equal to the curvature radius r of the corresponding sector-shaped recess 4025 disposed on the outer surface 4024 of the lower ring 4020 s Each first portion 4217 is connected to the lower ring 4020 by two first fasteners 4270. An adhesive (not shown) may be used to enhance the connection between the first portion 4217 and the lower ring 4020 by bonding the bottom plate portion 4237 to the scalloped recess 4025. The adhesive may prevent wear between the components due to cyclic loading, and may also prevent degradation (e.g., corrosion) due to exposure to environmental factors. In alternative embodiments, the first portion may have any desired form (e.g., a curved top plate portion).

[0100] In the illustrated embodiment, each first fastener 4270 is configured as an assembly including a threaded rod, a washer, and a nut. The threaded rod engages an internal thread provided on the first portion 4217. In alternative embodiments, each first fastener may have any desired arrangement (e.g., a hexagon socket screw, two nuts provided on opposite ends of the threaded rod instead of an internal thread on the first portion, and a screw or flange stud passing through the first portion and screwed into an internal thread provided on the lower ring). In other alternative embodiments, each first fastener may be provided with a different arrangement (e.g., a threaded rod, a washer and a nut for one of the first fasteners and a hexagon socket screw for another of the first fasteners). In other alternative embodiments, there may be a greater or lesser number of first fasteners.

[0101] The first fastener 4270 extends through the lower ring 4020, the bottom plate portion 4237, and the linear top plate portion 4221. When so arranged, the bottom plate portion 4237 is attached to the lower ring 4020. In an alternative embodiment, the first fastener, the lower ring, and / or the first portion can be sized and configured so that the first fastener does not extend through the bottom plate portion or the linear top plate portion. For example, the first fastener can be made shorter so that the first fastener ends within the first portion instead of extending through the linear top plate portion.

[0102] The second portion 4219 is attached to the first portion 4217 by a plurality of second fasteners 4272. The second fasteners 4272 also attach the spokes 4200 to the protective cover 4215. In the illustrated embodiment, the second fasteners 4272 are eight hexagon socket screws aligned with each other. The threads of the hexagon socket screws engage with the internal threads provided on the second portion 4219. In alternative embodiments, the second fasteners may have any desired arrangement (e.g., a nut that engages with the threads of the hexagon socket screws instead of the internal threads on the second portion). In other alternative embodiments, there may be a greater or lesser number of second fasteners. In further alternative embodiments, the second fasteners may be offset from each other.

[0103] The second fastener 4272 extends through the linear top plate portion 4221 of the first part 4217, the spoke 4200, and the wall portion 4235 of the second part 4219. According to this arrangement, the spoke 4200 is effectively clamped between the first part 4217 and the second part 4219. An adhesive (not shown) can enhance the connection between these components by combining the first part 4217 and the second part 4219 with the spoke 4200. The adhesive can prevent wear between the various components due to cyclic loading, and can also prevent degradation (e.g., corrosion) caused by exposure to environmental factors. In an alternative embodiment, the second fastener, the second part, the spoke, and the first part can be sized and configured so that the second fastener does not extend through the wall portion of the second part or the linear top plate portion of the first part. For example, the second fastener can be made shorter so that the second fastener ends in the second part instead of extending through the wall portion. In other alternative embodiments, the orientation of the second fastener can be reversed so that the second fastener extends through the second part, then passes through the spoke, and engages with the internal thread provided on the first part. In further alternative embodiments, depending on the material used to manufacture the spoke, the second portion may be omitted. According to this example, the second fastener may include a nut and bolt, wherein the nut engages the surface of the spoke, or the threaded portion of the second fastener may engage with an internal thread provided on the spoke.

[0104] Thus, the spoke 4200 is attached to the lower ring 4020 by a protective cover 4215, which is composed of a first portion 4217 and a second portion 4219, a first fastener 4270 and a second fastener 4272. In particular, the first portion 4217 and the second portion 4219 and the second fastener 4272 attach the protective cover 4215 to the spoke 4200, and the first fastener 4270 attaches the bottom plate portion 4237 to the lower ring 4020. This arrangement provides a sturdy attachment mechanism for the spokes and allows for individual removal, maintenance and installation of individual spokes. In addition, the arrangement does not encroach on the spoke area designed to deflect, thereby ensuring that the non-pneumatic tire properly carries the applied load.

[0105] Although already Figures 1 to 22 Separate embodiments and variations are shown and described in the present invention, but the disclosed features are not exclusive to each of the embodiments. Instead, various features can be combined between the embodiments as desired. For example, Figures 15 to 17 The arrangement of the spokes with protective covers shown in Fig.12 and Fig.12a The curved connecting portion combination of the spokes shown in FIG.

[0106] To the extent that the terms "including" or "having" are used in the specification or claims, they are intended to be inclusive in a manner similar to how the term "comprising" is understood when used as a transitional word in a claim. Furthermore, to the extent that the term "or" is employed (e.g., A or B), the term is intended to mean "A or B or both." When 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, the use of the term "or" herein is inclusive and does not have an exclusive use. See Bryan A. Garner, A Dictionary of Modern Legal Usage 624 (2d. Ed. 1995). In addition, to the extent the terms "in" or "into" are used in the specification and claims, the terms are intended to additionally mean "on" or "onto." Furthermore, to the extent the term "connected" is used in the specification or claims, the term is intended to mean not only "directly connected to," but also "indirectly connected to," such as connected through another component or components.

[0107] While the present application has been illustrated by descriptions of its embodiments, and while the embodiments have been described in considerable detail, it is not the intention of the applicant to restrict or in any way limit the scope of the appended claims to such details. Additional advantages and modifications will be apparent to those skilled in the art. Therefore, in its broader aspects, the present application is not limited to the specific details, representative apparatus and methods, and illustrative examples shown and described. For example, each spoke may be provided with a rubber coating to cushion shock when contact occurs between adjacent spokes. Therefore, departures from such details may be made without departing from the spirit or scope of the applicant's overall inventive concept.

Claims

1. A non-pneumatic tire, comprising: a lower ring having a first diameter; an upper ring having a second diameter, the upper ring being substantially coaxial with the lower ring; and a support structure connecting the lower ring to the upper ring, the support structure being comprised of a plurality of spokes arranged into a first spoke group and a second spoke group axially spaced from the first spoke group, each spoke of the plurality of spokes comprising: connected to a first end of the lower ring; A second end connected to the upper ring; and A boot at the first end has a base portion attached to the lower ring to connect the first ends of the spokes to the lower ring.

2. The non-pneumatic tire according to claim 1, wherein the lower ring is provided with a plurality of scalloped recesses, each of the plurality of scalloped recesses having a first curved surface, and wherein the bottom plate portion of the protective cover is provided with a second curved surface. 3 . The non-pneumatic tire according to claim 2 , wherein each of the first curved surface and the second curved surface is convex relative to an inner surface of the lower ring.

4. The non-pneumatic tire of claim 2, wherein the first curved surface has a first radius of curvature and the second curved surface has a second radius of curvature, and wherein at least one of the first radius of curvature and the second radius of curvature is constant.

5. The non-pneumatic tire of claim 2, wherein the first curved surface has a first radius of curvature and the second curved surface has a second radius of curvature, and wherein at least one of the first radii of curvature is equal to the second radius of curvature.

6. The non-pneumatic tire of claim 2, wherein the first curved surface has a first radius of curvature, the second curved surface has a second radius of curvature, and the outer surface of the lower ring has a third radius of curvature, and wherein each of the first radius of curvature and the second radius of curvature is different from the third radius of curvature.

7. The non-pneumatic tire of claim 1, wherein the lower ring has a first width, the spokes have a second width, and the boot has a third width, and wherein the third width is equal to at least one of the first width and the second width.

8. The non-pneumatic tire of claim 1, wherein each of the plurality of spokes further comprises an end cap attached to an edge of the boot.

9. The non-pneumatic tire of claim 8, wherein the boot has a first profile and the end cap has a second profile, and wherein the second profile is substantially the same as the first profile.

10. The non-pneumatic tire of claim 1, wherein each spoke of the plurality of spokes comprises: a toggle portion between the first end and the second end, the toggle portion being concavely curved relative to the lower ring; as well as A transition portion is located between the first end and the toggle portion, the transition portion being convexly curved relative to the lower ring.

11. A method of manufacturing a non-pneumatic tire, the method comprising the steps of: providing a lower ring having a first diameter and an upper ring having a second diameter greater than the first diameter; A plurality of sector-shaped recesses are formed on the lower ring, each of the plurality of sector-shaped recesses having a first curved surface; forming a plurality of spokes, each spoke extending between a first end and a second end; forming a plurality of protective covers, each protective cover of the plurality of protective covers having a second curved surface; attaching one of the plurality of protective covers to a corresponding one of the plurality of spokes at the first end; arranging the plurality of spokes into a first spoke group and a second spoke group axially spaced from the first spoke group; as well as The lower ring is connected to the upper ring using the first spoke group and the second spoke group, and the step of connecting the lower ring to the upper ring includes: attaching the second curved surface of the protective cover to the first curved surface of one of the plurality of scalloped recesses to connect the first end of the spoke to the lower ring; and connecting the second end of the spoke to the upper ring.

12. The method of manufacturing a non-pneumatic tire according to claim 11, wherein forming a plurality of scallops comprises: The first curved surface is disposed as a first convex surface relative to an inner surface of the lower ring, and wherein forming a plurality of protective covers includes disposing the second curved surface as a second convex surface relative to the inner surface of the lower ring.

13. The method of manufacturing a non-pneumatic tire according to claim 11, wherein forming a plurality of scallops comprises: The first curved surface is provided with a first radius of curvature, and wherein forming a plurality of protective covers includes providing the second curved surface with a second radius of curvature, wherein the first radius of curvature and the second radius of curvature are different from a third radius of curvature of an outer surface of the lower ring.

14. The method for manufacturing a non-pneumatic tire according to claim 11, further comprising the steps of: forming a plurality of end caps; as well as Attaching one of the plurality of end caps to an edge of a corresponding one of the plurality of protective covers.

15. The method of manufacturing a non-pneumatic tire of claim 14, wherein forming a plurality of end caps comprises: Each of the plurality of end caps is formed to have a first profile, and wherein forming a plurality of protective covers includes forming each of the plurality of protective covers to have a second profile, wherein the first profile is substantially the same as the second profile.

16. The non-pneumatic tire of claim 1, wherein the boot includes fasteners that attach the base plate portion to the lower ring.

17. The non-pneumatic tire of claim 1, wherein the boot comprises a first portion and a second portion, the first portion and the second portion being separate components.

18. The non-pneumatic tire of claim 17, wherein the first end of the spoke is sandwiched between the first portion and the second portion of the boot.

19. The non-pneumatic tire of claim 18, wherein the boot includes a fastener, the fastener and the first and second portions of the boot attaching the boot to the first end of the spoke.

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