Flexure member for a spoke component of a non-pneumatic tire

Abstract

A non-pneumatic tire is disclosed that includes an inner support ring coaxially disposed within an outer support ring, with a support structure connecting the rings. The support structure includes a plurality of spokes secured to the inner and outer support rings. Flexible members having filleted circumferential surfaces are used to attach the ends of the spokes to the outer support ring.

Description

[Technical Field]

[0001] The present disclosure relates to a flexible member for spoke components of a non-pneumatic tire, and more particularly to a flexible member having a rounded periphery for attaching the ends of the spoke components to a support ring of the non-pneumatic tire. [Background technology]

[0002] Non-pneumatic tire construction allows the tire to operate in an uninflated state and does not require inflation. Non-pneumatic tires may include support structures such as spokes or webbing that provide a compression zone and attach an inner support ring to an outer support ring. The inner support ring is positioned near the hub, and the outer support ring may incorporate and attach a circumferential tread.

[0003] The ends of the spokes for non-pneumatic tires are attached to inner and outer support rings. During tire operation, the spokes compress and elongate, potentially deflecting the spoke ends relative to one another and creating stresses in the spokes. The spoke ends, attached to the outer support ring near the tire's tread, experience forces from the tread as the tire rolls over the ground, deflecting the spoke ends and creating stresses at the attachment points.

[0004] The present invention aims to reduce the stress imparted to the attachment points of the spoke ends and in some cases redirect the stress away from the bond area between the surfaces to improve the durability of the attachment points. Summary of the Invention

[0005] In a first aspect, an outer support ring is provided. A non-pneumatic tire is disclosed that includes an inner support ring disposed inside an outer support ring, and a support structure disposed between the outer support ring and the inner support ring, the support structure including spokes, the spokes having first ends secured to the inner support ring and second ends secured to a flexible member, the flexible member having an inner surface, an outer surface, and a circumferential surface, the entire circumferential surface being filleted or at least two or more sides of the circumferential surface being filleted.

[0006] In one example of embodiment 1, to secure the second ends of the spokes to the outer support ring, the inner surface of the flexible member is secured to the second ends of the spokes and the outer surface of the flexible member is secured to the outer support ring.

[0007] In another example of embodiment 1, the filleted peripheral surface is disposed between, intersecting and contacting the inner and outer surfaces of the flexible member.

[0008] In another example of embodiment 1, the flexible members are disposed between the second ends of the spokes and the outer support ring, and the second ends of the spokes do not contact the outer support ring.

[0009] In another example of embodiment 1, the filleted peripheral surface has a concave shape.

[0010] In another example of embodiment 1, the concave shape of the filleted peripheral surface is continuous without a flat, linear, planar portion, and the filleted peripheral surface extends from the intersection with the inner surface to the intersection with the outer surface. In another example, the concave shape of the filleted peripheral surface can include a flat, linear portion, for example, at or near a central waist portion of the filleted peripheral surface.

[0011] In another example of embodiment 1, the concave shape of the filleted peripheral surface has a circular radius, an elliptical arc, or a combination thereof.

[0012] In another example of embodiment 1, the filleted circumferential surface includes substantially all, and in one example the entire, of the outer surface of the flexible member disposed between the inner and outer surfaces of the flexible member, and the filleted circumferential surface of the flexible member has two or more faces having a filleted surface. The two or more faces are disposed so as to face in opposite directions from one another. In another example, each of the two or more faces faces in a direction that is not the same as or aligned with another face.

[0013] In another example of embodiment 1, the filleted peripheral surface of the flexible member is comprised of four or more faces having a filleted surface, and in another example, each of the four or more faces faces in a direction that is not the same as or aligned with another face.

[0014] In another example of embodiment 1, two or more, three or more, or four or more faces of the filleted circumferential surface of the flexible member intersect with each other or with another circumferential surface to form one or more corners along the filleted circumferential surface, and one or more corners of the filleted circumferential surface are filleted corner faces. The one or more filleted corner faces can be oriented in a direction that is not the same as or aligned with any other circumferential surface.

[0015] In a second aspect, a flexible member for a non-pneumatic tire is disclosed, the flexible member including an inner surface, which can have a linear, curved, or other shape, such as a plane that matches a spoke end surface, an outer surface, which can have a linear, curved, or other shape, such as a plane that matches an outer support ring surface, a circumferential side surface disposed between the inner and outer surfaces, the side surface extending around the entire circumference of the flexible member, the circumferential side surface having two or more rounded surface surfaces, the two or more rounded surface surfaces not facing in the same direction as each other.

[0016] In one example of embodiment 2, the plane (e.g., linear, curved) of the inner surface has a perimeter defined by a plurality of peripheral edges that form two or more, three or more, or four or more connection points or corners where the peripheral edges intersect with one another, and the two or more, three or more, or four or more connection points or corners along the linear plane of the inner surface contact a portion of the rounded concave surface of the lateral peripheral surface of the flexible member.

[0017] In another example of aspect 2, the plane (e.g., linear, curved) of the outer surface has a perimeter defined by a plurality of peripheral edges that form two or more, three or more, or four or more connection points or corners where the peripheral edges intersect with one another, and the two or more, three or more, or four or more connection points or corners along the linear plane of the outer surface contact a portion of the rounded concave surface of the side peripheral surface of the flexible member.

[0018] In another example of embodiment 2, the two or more rounded concave surfaces have a circular shape, an elliptical shape, a parabolic shape, or a combination thereof.

[0019] In another example of embodiment 2, the two or more rounded face surfaces are concave surfaces.

[0020] In another example of aspect 2, each of the two or more rounded face surfaces includes a first end or bottom end and a second end or top end, where the first end intersects with the periphery of the inner surface of the flexible member and the second end intersects with the periphery of the outer surface of the flexible member.

[0021] In another example of aspect 2, the circumferential surface includes four side surfaces that define the entire periphery or substantially the entire periphery, e.g., except for filleted or concave corner surfaces around the periphery of the flexible member between the inner and outer surfaces, each of the four side surfaces having a concave shape and intersecting to form four corners along the circumferential surface, each of the four corners of the circumferential surface being a filleted or concave corner circumferential surface.

[0022] In another example of embodiment 2, the four side surfaces are rounded. The four corners can have the same or similar shape as one or more of the four side surfaces of the periphery of the flexible member, such as concave or convex rounded surfaces.

[0023] In another example of embodiment 2, the inner surface of the flexible member is secured to a spoke of the non-pneumatic tire. The inner surface can be positioned to face or be oriented radially inward relative to a central portion of the non-pneumatic tire.

[0024] In another example of embodiment 2, the outer surface of the flexible member is secured to an outer support ring of the non-pneumatic tire. The outer surface can be positioned to face radially outward from a central portion of the non-pneumatic tire or toward the outer support ring.

[0025] In a third aspect, a flexible member for a non-pneumatic tire is disclosed, the flexible member including an inner surface having a planar surface, an outer surface having a planar surface, and a circumferential side surface disposed between the inner and outer surfaces, the side surfaces extending around the entire circumference of the flexible member, the circumferential side surface having two or more, three or more, or four or more rounded side surfaces curving inward from a periphery of the inner surface, the outer surface, or both the inner and outer surfaces of the flexible member, wherein the two or more, three or more, or four or more rounded side surfaces do not face in the same direction as each other.

[0026] In one example of the third aspect, two, three, or more rounded face surfaces of the flexible member form a recess around a portion of the lateral periphery, and the rounded face surfaces have a filler material within the recess. The filler material is a different material from the material forming the flexible member. In one example, the filler material has a reduced stiffness compared to the stiffness of the material forming the flexible member.

[0027] In another example of embodiment 3, the filler material in the recess around a portion of the side periphery does not extend beyond the periphery of the inner surface, the periphery of the outer surface, or the periphery of both the inner and outer surfaces of the flexible member.

[0028] In another example of embodiment 3, the filler material occupies all or substantially all of the recess around the peripheral surface of the flexible member.

[0029] In another example of the third aspect, the filler material forms a linear or flat surface on the peripheral surface of the flexible member. The linear or flat surface formed by the filler material within the recess extends from the periphery of the inner surface to the periphery of the outer surface of the flexible member.

[0030] In another example of embodiment 3, the filler material within the recess extends outward from or beyond the periphery of the inner surface of the flexible member, the periphery of the outer surface, or both surfaces.

[0031] In another example of embodiment 3, the filler material forms a layer on the lateral circumferential surface of the flexible member.

[0032] In a fourth aspect, a flexible member for a non-pneumatic tire is disclosed, the flexible member including one of a mold parting line, a witness mark, a mold vent mark, flashing, or other surface imperfections created during a molding process used to make the flexible member, whereby one or more of the mold parting line, witness mark, mold vent mark, flashing, or other surface imperfections are spaced from any corner side peripheral surface areas or filleted corner side peripheral surface areas.

[0033] In an example of embodiment 4, the corner side surface or filleted corner side surface formed by the intersection of the side surfaces or surfaces of the flexible member is free of one or more of mold parting lines, witness marks, mold vent marks, flashing, or other surface defects generated during the molding process.

[0034] In another example of embodiment 4, any of the mold parting lines, witness marks, mold vent marks, flashing, and / or surface imperfection marks present on the outer surface of the flexible member are spaced at least 5 millimeters (mm), at least 8 mm, at least 10 mm, or at least 15 mm from the corner side periphery or filleted corner side periphery.

[0035] In another example of embodiment 4, any of the mold parting lines, witness marks, mold vent marks, flashing and / or surface imperfection marks present on the outer surface of the flexible member are located between or substantially centered between two corner side peripheral surfaces, for example, on the peripheral surface or filleted surface of the flexible member.

[0036] The above aspects (or examples of these aspects) may be provided alone or in combination with any one or more of the example aspects or example aspects described above. For example, the first aspect may be provided alone or in combination with any one or more of the example aspects of the first, second, third, or other aspects described above.

[0037] Additional features and advantages are set forth in the following Detailed Description, and in part will be readily apparent to those skilled in the art from this description or will be recognized by practicing the embodiments described herein, including the following Detailed Description, Claims, and Accompanying Drawings. [Brief explanation of the drawings]

[0038] The present disclosure is better understood from the following detailed description when read in conjunction with the accompanying drawings. [Figure 1] FIG. 1 shows a side view of one embodiment of a non-pneumatic tire. [Figure 2] FIG. 2 shows a cross-sectional view taken along line 3-3 of FIG. [Figure 3] FIG. 3 shows a detailed side view of section A of FIG. 1, with some features removed for clarity. [Figure 4] FIG. 4 is a detailed view of a single spoke and flexible member of a non-pneumatic tire. [Figure 5] FIG. 5 shows a perspective view of a flexible member that attaches the spoke ends to the support members of a non-pneumatic tire. [Figure 6] FIG. 6 shows a rear view of the flexible member of FIG. [Figure 7] FIG. 7 shows a side view of the flexible member of FIG. [Figure 8] FIG. 8 shows a side view of an example flexible member having a filler material occupying recesses in the periphery of the flexible member. DETAILED DESCRIPTION OF THE INVENTION

[0039] The terminology used herein is for the purpose of describing the embodiments only and should not be construed as limiting the invention as a whole.

[0040] As used herein, when a range is given, such as 5 to 25 (or 5 to 25), this range preferably means at least 5 or greater than 5, and separately and independently preferably no greater than 25 or less than 25. In some instances, such ranges independently specify 5 or greater, and separately and independently no greater than 25.

[0041] The following contains definitions of selected terms used herein. The definitions include various examples 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 singular and plural forms of a term may fall within the scope of the definition.

[0042] "Axial" and "axially" refer to directions parallel to the axis of rotation of the tire.

[0043] "Circumferential" and "circumferentially" refer to a direction extending along the perimeter of the surface of the tread perpendicular to the axial direction.

[0044] "Radial" and "radially" refer to directions perpendicular to the axis of rotation of the tire.

[0045] 1-3 illustrate one embodiment of a non-pneumatic tire 10. The non-pneumatic tire 10 is merely exemplary and is not intended to be limiting. The non-pneumatic tire 10, along with the other embodiments of non-pneumatic tires shown, may be used on the wheels of vehicles or other related articles, such as cars, trucks, heavy vehicles, trailers, all-terrain vehicles, off-road vehicles, buses, airplanes, tractors, motorcycles, bicycles, and any other type of passenger vehicle.

[0046] The non-pneumatic tire 10 includes an inner support ring 20. The inner support ring 20 may engage or directly contact a vehicle hub (not shown) to secure the tire 10 to the vehicle or related article. The inner support ring 20 has a radially inwardly facing inner surface 23 and a radially outwardly facing outer surface 24 and may be made from a polymeric material, an elastomeric material, a metal, a composite material composed of a polymer or resin reinforced with glass or carbon fiber, or any other suitable material or combination of materials.

[0047] The non-pneumatic tire 10 may include an annular outer support ring 30 disposed radially outward from the inner support ring 20 and components disposed between the rings 20, 30. The outer support ring 30 may have a diameter measured along its inner surface 33 that is larger than the diameter of the inner support ring 20 measured along its inner surface 23 and may be aligned and coaxial with the inner support ring 20 as shown. As shown in FIG. 2 , the outer support ring 30 has a radially inward-facing inner surface 33 and a radially outward-facing outer surface 34 and may be made from a polymeric material, an elastomeric material, a metal, a composite material composed of a polymer or resin reinforced with glass or carbon fiber, or any other suitable material or combination of materials. A circumferential tread 70 is attached to the outer surface 34 of the outer support ring 30. The circumferential tread 70 may be attached to the outer support ring 30 adhesively, mechanically, or in any other suitable arrangement. As shown, the radially inwardly facing inner surface of the circumferential tread 70 may be in direct contact with the outer surface 34 of the outer support ring 30 .

[0048] As shown in FIG. 2 , the circumferential tread 70 includes a tread band 72 and a tread layer 74. The tread band 72 may be directly adhered to the exterior surface 34 or may be in contact with the exterior surface 34. 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, studs, or any other desired elements. The tread band 72 may include a filament assembly.

[0049] As also shown in FIG. 2 , the tread band 72 may be a single layer. In alternative embodiments, the tread band 72 may be a multi-layer band. Such a multi-layer tread band may include one or more layers of substantially inextensible material or extensible material. The layers may be formed from sheets of material, cords of material, filaments of material, or any other desired arrangement. In the illustrated embodiment, the tread band 72 is shown as a single layer. In alternative embodiments, the tread band may be a multi-layer band. Such a multi-layer tread band may include one or more layers of substantially inextensible material. The layers may be formed from sheets of material, cords of material, filaments of material, or any other desired arrangement. In other alternative embodiments, the multi-layer tread band may include layers of extensible material, such as an elastomer. According to one exemplary embodiment, the tread band may include a pair of inextensible layers separated by a layer of extensible material. In yet other alternative embodiments, the tread band may include bands referred to as shear bands, shear elements, or thin annular high strength band elements.

[0050] A support structure 100 is positioned radially inward from the circumferential tread 70 and the outer support ring 30. The support structure 100 includes, for example, one or more spokes 200, connecting the inner support ring 20 to the outer support ring 30, as shown in FIG. 1 . As shown in FIGS. 1 and 2 , the support structure 100 extends from the outer surface 24 of the inner support ring 20 to the inner surface 33 of the outer support ring 30 and is made up of a plurality of individual spokes 200. The plurality of spokes 200 may be arranged in one or two axially spaced-apart spoke groups, which may include, as shown, a first group of spokes 202 and a second group of spokes 204 axially spaced from the first group of spokes 202. In an alternative configuration, the support structure may include three or more axially spaced-apart spoke groups, for example, three, four, or more groups.

[0051] 2 are axially spaced apart from one another, which may be any suitable distance to ensure that the spokes from each group or groups do not contact one another. The spoke groups may be configured such that each spoke 200 of the first group 202 is substantially convex relative to the clockwise circumferential direction of the non-pneumatic tire 10 and each spoke of the second group 204 is substantially concave relative to the clockwise circumferential direction of the non-pneumatic tire 10, or vice versa.

[0052] Spoke 200 may be manufactured from a metal such as steel or aluminum, a polymer such as polyester or nylon, a composite material such as fiberglass or carbon fiber reinforced polymer, or any other suitable material or combination of materials. Spoke 200 may also include a reinforcement (not shown), such as a metal wire, a metal or fiber cord, chopped fiber, a reinforcing filler, and combinations thereof. Spoke 200 shown in FIG. 4 has a substantially rectangular cross-section extending radially between first end 206 and second end 208 and including a first surface 210 and a second surface 212 facing opposite first surface 210. Spoke thickness t refers to the distance between first surface 210 and second surface 212. In the embodiments of FIGS. 3 and 4, spoke 200 has a constant thickness between first end 206 and second end 208. In alternative embodiments, the thickness of the spoke may vary between the first end and second end. For example, the spokes may have relatively thick portions at the first and second ends and a relatively thin portion between the ends. In other alternative embodiments, the spokes may have any desired cross-sectional shape (e.g., circular, diamond, hexagonal, etc.) or a combination of different cross-sectional shapes.

[0053] The second ends 208 of the spokes 200 are provided with flexible members 216 for securing the spokes 200 to a surface (e.g., inner surface 33) of the outer support ring 30. As shown in FIGS. 3 and 4 , the flexible members 216 are disposed between the second ends 208 of the spokes 200 and the outer support ring 30, e.g., secured or fixed thereto. The second ends 208 of the spokes 200 are shown with a first surface 208 a and a second surface 208 b. Depending on the orientation of the spokes 200, the first surface 208 a faces radially outward toward the outer support ring 30 and provides a surface for the flexible members 216 to contact the spokes 200 and attach the second ends 208 of the spokes to the outer support ring 30.

[0054] The flexible member 216, which is disposed radially relative to the non-pneumatic tire 10, includes an inner surface 216a and an outer surface 216b. The inner surface 216a of the flexible member 216 faces radially inward toward the inner support ring 20 and the spokes 200, forms a contoured (e.g., linear, curved) plane to match the first surface 208a, and is secured to the first surface 208a of the second end 208. The outer surface 216b of the flexible member 216 faces radially outward toward the outer support ring 30, forms a contoured (e.g., linear, curved) plane to match the inner surface 33 of the outer support ring 30, and is secured to the inner surface 33 of the outer support ring 30. The inner surface 216a and the outer surface 216b may be secured to another surface by any suitable means, for example, with mechanical fasteners, welding, or adhesives. If adhesive is used, the inner and outer surfaces 216a, 216b of the flexible members and / or spokes and outer support ring can be cleaned to remove any debris, release materials, or other surface compounds that may reduce bonding between the surfaces. The adhesive can be applied to the exposed surfaces to be secured together. For example, the adhesive may be applied to the inner or outer surfaces of the flexible members, the second ends of the spokes, the outer support ring, or any combination thereof. The adhesive can be any suitable adhesive (e.g., epoxy, hot melt adhesive, etc.) for securing surfaces together. Exemplary epoxy adhesives can include, but are not limited to, Chemlok® adhesive and / or a primer. In another example, a primer material can be applied to the exposed surfaces to enhance bonding of the surfaces.

[0055] The inner surface 216a and the outer surface 216b have perimeters that define the outer contour or circumference of the surfaces 216a, 216b. In one or more embodiments, the inner surface 216a and the outer surface 216b each have four perimeters, two circumferential perimeters and two axial perimeters. The perimeters of the inner surface 216a and the outer surface 216b form corners or connection points that meet the upper or lower edges of the filleted or rounded side perimeter surfaces. To contact or secure to the first surface 208a of the second end 208, one or more perimeters of the inner surface 216a can be aligned or flush with the perimeters of the first surface 208a of the second end 208. For example, the circumferential perimeters of the inner surface 216a can be aligned with the circumferential edges of the first surface 208a. In another example, the axial periphery of the inner surface 216a may be aligned with the axial edge of the spoke second end 208. In alternative embodiments, one or more peripheries of the inner surface 216a may be disposed inwardly of the periphery of the first surface 208a such that one or more portions of the first surface 208a of the second end 208 are exposed and are not covered by either the inner or outer surface of the flexible member 216. In one or more embodiments, the flexible member 216 may be provided as a rectangular parallelepiped, and the ends of the flexible member 216 may be aligned with the second ends 208 of the spokes 200, positioned so that they are set back from the second ends of the spokes, or positioned so that the ends of the flexible member extend beyond the second ends of the spokes.

[0056] The flexible member 216 has a first width extending axially along the tire, a second width extending circumferentially along the tire, and a height extending radially along the tire. The axial and circumferential widths of the flexible member vary along its height, and the height of the flexible member may vary along its axial or circumferential width.

[0057] The height (h) of the flexure members 216, extending radially and measured between the inner surface 216a and the outer surface 216b as shown in FIG. 4, forms the circumferential side surface 220. The height (h) of the flexure members 216 may be constant in some embodiments, and may vary in other embodiments depending on the spoke surface geometry relative to the inner surface of the outer support ring. In one example, the height of the flexure members may be constant axially or may vary circumferentially (e.g., increasing from one circumferential end to the opposite circumferential end). In another example, the height of the flexure members may be lowest at the circumferential ends of the spokes and increase (e.g., by a constant amount) as one moves radially inward away from the ends of the spokes, achieving a maximum height at the opposite circumferential end of the flexure members.

[0058] The circumferential and axial widths of the flexible member 216 vary both circumferentially and axially along its height (h). This is because the circumferential side surface 220, i.e., the side surface between the inner surface 216a and the outer surface 216b, is filleted (e.g., along the entire circumferential surface) or has two or more, three or more, four or more, or five or more rounded face surfaces. The circumferential side surface and its faces can have any concave shape or combination of concave shapes, such as elliptical, partial circular, or irregular shapes. The shape of the filleted or rounded surface preferably has a constant curvature or a smooth tangential transition from the periphery of 216a to the periphery of 216b, which forms the end point of the circumferential surface. The intersection of the circumferential surface with the periphery of 216a, 216b forms a stress buildup that can lead to fatigue cracking of the flexible member 216 near the attachment points to the spokes. The multiple or full circumferential filleted side circumferential surfaces 220 serve to distribute stress along the intersection lines to the central region of the flexure 216, reducing fatigue cracking.

[0059] The filleted surface of side peripheral surface 220 may have an inset distance. The inset distance is measured by determining the distance between the central waist portion (i.e., the narrowest point) of the peripheral surface and an imaginary plane extending from the periphery of 216a to the periphery of 216b at the endpoint of the peripheral surface. The inset distance may be in the range of 0.2 to 2.5 times, 0.5 to 2.25 times, or 1 to 2 times the height of an imaginary plane extending from the periphery of 216a to the periphery of 216b at the endpoint of the peripheral surface.

[0060] The circumferential side surface 220 may not contact any structural component of the non-pneumatic tire 10 such that the surface 220 is directly exposed to the surrounding environment (e.g., air). The circumferential side surface 220 may have any suitable shape and one or more sides, e.g., two to eight or more sides, that form a surface having surface planes, e.g., curved, rounded, or concave, that face or point in non-identical directions. In Figures 2 and 3, the flexible member 216 is shown with a concave circumferential side surface extending between the contact with the outer support ring 30 and the spoke ends 208.

[0061] The filleted or rounded side peripheral surfaces form a central waist portion between the inner surface 216a and the outer surface 216b, which has a minimum circumferential width, axial width, or both. The circumferential width and axial width increase in both directions from the central waist portion along the height (h), such that the maximum circumferential and axial widths radially inward and outward from the central waist portion occur at the inner surface 216a and the outer surface 216b of the flexible member 216.

[0062] As shown in FIGS. 5 and 6 , the central waist portion 216c is located at the midpoint of the circumferential side surface 220, and the circumferential and axial widths of the flexible member 216 increase continuously, without any flat, linear planar portions, radially inward relative to the inner surface 33 of the outer support ring 30 and radially outward relative to the first surface 208a of the second end 208 of the spoke 200. Although not shown, in an alternative design, the waist portion 216c may be near or adjacent to the center point of the circumferential side surface 220. The two circumferential surfaces of the flexible member 216 are filleted, with rounded surfaces extending from the circumferential periphery of the inner surface 216a to the outer surface 216b. The two axial circumferential surfaces of the flexible member 216 are filleted, with rounded surfaces extending from the axial periphery of the inner surface 216a to the outer surface 216b.

[0063] The central waist portion 216c represents the smallest diameter or width (axial or circumferential) of the flexible member 216. The central waist portion 216c may have an average diameter, axial width, or circumferential width in the range of 5 mm to 130 mm, 6 mm to 110 mm, 7 mm to 100 mm, 8 mm to 80 mm, 9 mm to 70 mm, or 10, 11, 12, 13, or 14 mm, or 20, 25, 30, 35, 40, 45, 50, or 60 mm. In other embodiments, the central waist portion 216c may have an average diameter, axial width, or circumferential width that is less than 25 mm, less than 20 mm, or less than 15 mm, and greater than 6 mm, 7 mm, or 8 mm. In other examples, central waist portion 216c can have an average diameter, axial width, or circumferential width greater than 50 mm, greater than 80 mm, or greater than 100 mm, and less than 130 mm, 125 mm, or 120 mm. The axial or circumferential width of central waist portion 216c can be compared to the maximum axial or circumferential width located at inner surface 216a and outer surface 216b of flexible member 216. In one or more embodiments, the axial or circumferential width at inner surface 216a or outer surface 216b compared to the axial or circumferential width at central waist portion 216c can be in a ratio range of 0.5 to 8.5, 0.75 to 6.5, 1 to 5, 1.25 to 4, or 1.5 to 2.5.

[0064] The circumferential and axial circumferential surfaces of the flexible member 216 form four circumferential surfaces that may have filleted surfaces. In certain embodiments, the circumferential and axial circumferential surfaces or four circumferential surfaces of the flexible member 216 form the entire circumferential side surface 220 of the member. As shown in FIG. 5 , the filleted circumferential surface intersects with the filleted axial circumferential surface. The intersection of the circumferential and axial surfaces may form one or more corners (e.g., 2, 4) along the filleted circumferential surface. The corners may have a rounded curvature that is the same shape as the intersecting circumferential and axial surfaces. The corner edge formed by the intersecting circumferential and axial surfaces may be softened by forming a corner side surface or surface. FIG. 5 shows a corner side surface 228 that transitions the circumferential and axial surfaces to a smoother surface compared to a sharp corner edge. The circumferential side surface 220 of the flexible member 216 can have one or more circumferential corner surfaces 228, e.g., one, two, three, or four circumferential corner surfaces. When the circumferential side surface 220 of the flexible member 216 includes one or more circumferential corner surfaces 228, it can have five or more filleted circumferential surfaces, e.g., six, seven, or eight filleted circumferential surfaces.

[0065] 6 illustrates a filleted circumferential surface disposed between two filleted corner surfaces 228 that are similarly adjacent to each filleted axial surface of the flexible member 216. The filleted corner surfaces 228 extend with a continuous rounded surface between the peripheries of the inner and outer surfaces 216 a, 216 b of the flexible member 216. The filleted corner surfaces 228 help reduce stress imparted to the attachment points of the spoke ends 208 a and, in some cases, redirect stress away from the interface region between the spoke ends 208 and the inner surface 33 of the outer support ring 30, improving the durability of the attachment points of the flexible member 216.

[0066] 7 shows a filleted axial circumferential surface disposed between two filleted corner side surfaces 228 that similarly adjoin each filleted circumferential surface of flexible member 216. Filleted corner side surfaces 228, like the circumferential and axial side surfaces, extend with a continuous rounded surface between the peripheries of inner surface 216a and outer surface 216b of flexible member 216, which are secured to first surface 208a of second end 208 of spoke 200 and inner surface 33 of outer support ring 30, respectively.

[0067] The flexible member 216 shown in the figures may be fabricated from a polymeric material (e.g., urethane, resin, rubber), metal, or any other suitable material or combination of materials. Preferably, the flexible member 216 is prepared using a material suitable for introduction (e.g., pouring) into a mold to form the desired shape, including the entire filleted side perimeter of the flexible member 216. The material is flowable for injection or pouring into the mold, such as a liquid urethane composition. The material is cured or hardened in the mold, for example, under heated conditions, and then removed for use and fastening to the spokes 200 and outer support ring 30. The flexible member 216 can be cleaned to remove any release material present on the surface, and grinding or polishing can be used to remove barbs, witness marks, mold parting lines, mold vent marks, or other irregularities resulting from the molding process.

[0068] The mold tool used to form the flexible member 216 must be removed after the member has cured to expose the finished part. For example, the mold tool is disassembled into multiple pieces along parting lines or joints to release the formed flexible member. The mold tool may be made from multiple pieces, and the connection or mating points and / or injection points of the pieces may imprint mold parting lines or other marks (witness marks) on the finished flexible member. Flash may also often be present at mold parting lines. The presence of mold parting lines or other marks in high-stress areas on the flexible member can affect the durability and performance of the part. In one example, mold parting lines can create small witness marks or defects in the surface that can act as stress risers. As discussed above, the corner side peripheral surface 228 helps reduce stress imparted to the spoke end attachment points and, in some cases, redirects stress away from the bond area between the spoke end and the inner surface of the outer support ring, improving the durability of the flexible member attachment points. The molding tool for forming the flexible member preferably includes fewer molded parts to reduce the amount of mold parting lines and other marks on the finished flexible member, and / or selectively positions or arranges mold parting lines and other marks away from areas of potential increased operating stress. By locating mold parting lines and other marks away from specific stress and strain areas of the flexible member, and therefore by not aligning them with potential high stress or strain areas, these areas are not adversely affected by any additional surface defects that could cause increased stress or strain. Similarly, mold vent locations, which may introduce potential sources of surface defects, should be located away from and avoided from potential areas of stress and strain within the flexible member.

[0069] In one or more embodiments, the flexible member does not include a mold parting line at or near any corner or filleted corner peripheral surface. In one example, any mold parting line on the flexible member is at least 5 millimeters (mm), at least 8 mm, at least 10 mm, or at least 15 mm away from any corner or filleted corner peripheral surface of the flexible member. In another example, any mold parting line is located between two corner peripheral surfaces or substantially centered between two corner peripheral surfaces, e.g., on a peripheral surface or filleted surface. By centering one or more mold parting lines between two corner peripheral surfaces, any potential surface defects imparted by the forming tool are optimally spaced from high stress and strain areas of the flexible member.

[0070] In another embodiment, the flexible member is free of witness marks, flashing, or mold vent marks at or near any peripheral corner or filleted corner surfaces. The witness marks, flashing, or mold vent marks are spaced from any peripheral corner or filleted corner surfaces of the flexible member, for example, at least 5 millimeters (mm), at least 8 mm, at least 10 mm, or at least 15 mm from any peripheral corner or filleted corner surface of the flexible member. In other embodiments, the witness marks, flashing, or mold vent marks are located between two peripheral corner surfaces or substantially centered between two peripheral corner surfaces, for example, on the periphery or filleted surface.

[0071] In one or more embodiments, the mold used to form flexible member 216 can include a non-pneumatic tire component as an interior wall of the mold. For example, the mold can include an opening that exposes the flexible member molding material within the mold, and the non-pneumatic tire component can be positioned to cover the opening or pre-assembled to close the opening prior to introducing the flexible member molding material into the mold cavity. The flexible member molding material directly contacts the surface of the non-pneumatic tire or some of its components and bonds to the component surface during curing. The cured flexible member is secured to the surface of the non-pneumatic tire component upon removal from the mold. In other embodiments, the mold used to form flexible member 216 can include two non-pneumatic tire components as interior walls of the mold. For example, the mold can include two openings that expose the flexible member molding material within the remainder of the mold cavity to two non-pneumatic tire components that are positioned to cover the opening or pre-assembled to close the opening prior to introducing the flexible member molding material into the mold cavity.

[0072] The non-pneumatic tire components can be any suitable part, such as spokes or an outer support ring. Using the non-pneumatic tire components as mold surfaces can reduce downstream process steps for attaching flexible member surfaces to the components. The non-pneumatic tire components can be cleaned of debris or residue before being aligned with the mold structure to form the molding surface to ensure proper bonding or adhesion of the flexible member molding material to the surfaces of the non-pneumatic tire components (e.g., the end faces of the spokes and / or the inner surface of the outer support ring). In one example, the spoke end surfaces are used as mold surfaces to form the inner surfaces 216a for bonding the spoke ends 208 to the flexible members 216. To enhance adhesion, the spoke end surfaces, which serve as mold surfaces, can be primed with an adhesion aid, such as an epoxy adhesive or a Chemlok® product. The spokes with attached flexible members 216 can then be secured to the outer support ring 30 during assembly of the non-pneumatic tire. In another example, the inner surface 33 of the outer support ring 30 is used as a molding surface for bonding the flexible member molding material to the outer support ring.

[0073] In one or more embodiments, the flexible member 216 can include a protective material around its perimeter surface. As shown in FIG. 8 , the flexible member 216 has an inner surface 216a and an outer surface 216b, and a peripheral side surface 2220 having a circumferentially rounded surface that curves inward from the periphery of the surfaces 216a, 216b. The rounded surface of the peripheral portion 220 forms a recess around the periphery. The recess can be filled with a filler material 300. The filler material 300 can be any suitable material, for example, a material different from that used to fabricate the flexible member 216. The filler material 300 is preferably a flexible, soft material that does not significantly interfere with any movement or flexing motion of the flexible member 216. The filler material 300 can be added to the recess formed by the rounded surface of the peripheral portion 220 after the flexible member 216 is secured to the spokes 200 and the outer support ring 30.

[0074] The infill material 300 forms a barrier between the surface of the side periphery 220 and the external environment surrounding the non-pneumatic tire, protecting the flexible member 216 from debris and environmental exposure. For example, the infill material 300 can reduce or eliminate debris that could otherwise contact and damage the side periphery surface 220 during operation of the non-pneumatic tire. Foreign objects (e.g., rocks) can strike the side periphery surface of the flexible member 216 and significantly damage the filleted surfaces that serve to distribute stress during operation. Cuts, voids, or similar damage can form weak points along the side periphery surface 220 of the flexible member 216. The infill material may also reduce direct exposure of the side periphery surface 220 to harmful gases, sunlight, and harmful ozone or other pollutants during operation. This protection can result in a longer and more durable lifespan for the flexible member 216.

[0075] 8 shows the filler material 300 extending past the recesses formed by the rounded face surfaces of the perimeter 220 and onto the first surfaces 208 a of the second ends 208 of the spokes 200 and the inner surface 33 of the outer support ring 30. In an alternative configuration, the filler material 300 may cover or coat the circumferential surface 220, e.g., as a layer, providing an outer protective surface. In another example, the filler material 300 may completely fill the recesses formed by the rounded face surfaces of the perimeter 220, but may not extend onto or significantly contact the first surfaces 208 a, the inner surface 33, or both. In this case, the filler material 300 may form a straight or flat surface on the circumferential surface 220 of the flexible member 216.

[0076] While various aspects and embodiments of the compositions and methods have been disclosed herein, other aspects and embodiments will be apparent to those of ordinary skill in the art. The various aspects and embodiments disclosed herein are for illustrative purposes only and are not intended to limit the true scope and spirit of the invention, as set forth in the appended claims.

Claims

1. A non-pneumatic tire, an outer support ring; an inner support ring disposed inside the outer support ring; a support structure disposed between the outer support ring and the inner support ring, the support structure including spokes, the spokes comprising: a first end fixed to the inner ring; 1. A non-pneumatic tire comprising: a support structure including a second end secured to a flexible member, the flexible member including an inner surface, an outer surface, and a filleted circumferential surface.

2. 2. The non-pneumatic tire of claim 1, wherein the inner surface of the flexible member is secured to the second ends of the spokes and the outer surface of the flexible member is secured to the outer support ring to secure the second ends of the spokes to the outer support ring.

3. The non-pneumatic tire of claim 1 , wherein the filleted circumferential surface is disposed between the inner and outer surfaces of the flexible member.

4. 2. The non-pneumatic tire of claim 1, wherein the flexible members are disposed between the second ends of the spokes and the outer support ring, and the second ends of the spokes do not contact the outer support ring.

5. The non-pneumatic tire of claim 1 , wherein the filleted circumferential surface has a concave shape.

6. 6. The non-pneumatic tire of claim 5, wherein the concave shape of the filleted circumferential surface is continuous from the line of intersection with the inner surface to the line of intersection with the outer surface without any flat, linear planar portions.

7. 6. The non-pneumatic tire of claim 5, wherein the concave shape of the filleted circumferential surface includes a flat, linear portion near a central waist portion.

8. The non-pneumatic tire of claim 6 , wherein the concave shape has a circular radius or an elliptical arc.

9. 10. The non-pneumatic tire of claim 1, wherein the filleted circumferential surface includes substantially all of the outer surface of the flexible member between the inner surface and the outer surface of the flexible member, and the filleted circumferential surface of the flexible member includes two or more faces having a filleted surface.

10. 10. The non-pneumatic tire of claim 9, wherein the filleted circumferential surface of the flexible member consists of four or more faces having a filleted surface.

11. 10. The non-pneumatic tire of claim 9, wherein the two or more faces of the filleted circumferential surface of the flexible member intersect with each other to form a corner along the filleted circumferential surface, the corner of the filleted circumferential surface being a filleted corner face.

12. 1. A flexible member for a non-pneumatic tire, comprising: an inner surface having a flat surface; an outer surface having a planar surface; a peripheral side surface disposed between the inner surface and the outer surface, the side surface extending around an entire circumference of the flexible member, the peripheral side surface including two or more rounded face surfaces.

13. 13. The flexible member of claim 12, wherein the plane of the inner surface includes a plurality of outer peripheral edges forming three or more connection points, the outer peripheral edges intersecting one another, and the three or more connection points along the plane of the inner surface contacting a portion of a rounded concave surface of the side peripheral surface of the flexible member.

14. 13. The flexible member of claim 12, wherein the plane of the outer surface includes a plurality of outer peripheral edges forming three or more connection points, the outer peripheral edges intersecting each other, and the three or more connection points along the plane of the outer surface contacting a portion of a rounded concave surface of the side peripheral surface of the flexible member.

15. The flexible member of claim 12 , wherein the two or more rounded concave surfaces have a circular shape, an elliptical shape, a parabolic shape, or a combination thereof.

16. The flexible member of claim 12 wherein the two or more rounded face surfaces are concave surfaces.

17. 13. The flexible member of claim 12, wherein each of the two or more rounded face surfaces includes a first end and a second end, the first end intersecting a periphery of the inner surface of the flexible member and the second end intersecting a periphery of the outer surface of the flexible member.

18. 13. The flexible member of claim 12, wherein the circumferential side surface includes four side surfaces defining a perimeter of the flexible member between the inner surface and the outer surface, each of the four side surfaces having a concave shape and intersecting to form four corners along the circumferential side surface, each of the four corners of the circumferential side surface being a filleted corner circumferential side surface.

19. 20. The flexible member of claim 18, wherein each of the four face surfaces is rounded.

20. 13. The flexible member of claim 12, wherein the inner surface of the flexible member is secured to a spoke of the non-pneumatic tire and the outer surface of the flexible member is secured to an outer support ring of the non-pneumatic tire.

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