Non-pneumatic tire comprising spokes

Abstract

To provide a non-pneumatic tire having a radially outer circumferential band portion, a radially inner hub portion, and a support structure including a plurality of spokes extending from the hub portion to the band portion, capable of reducing manufacturing complexity.SOLUTION: A radially outer foot of at least one spoke of the plurality of spokes is mechanically coupled to the band and / or removably attached to the band. In another aspect, the attachment surface of the spoke is at least partially formed by a material that is harder than the polymer composition of the spoke. Further, portions of the band portion and the hub portion adjacent to and in contact with the attachment surface are at least partially formed from one or more of the material and another material that is harder than the polymer composition.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a support structure, particularly a non-pneumatic tire including a plurality of spokes such as spokes of a polymer composition.

Background Art

[0002] Some non-pneumatic tires include a circumferential tread band and a circumferential hub portion connected to each other by a support structure including a plurality of spokes. It is difficult to manufacture such tires cost-effectively and / or in mass production. Further, in many types of tires, it is difficult to repair the support structure of such a damaged tire during use.

Summary of the Invention

Problems to be Solved by the Invention

[0003] The development of non-pneumatic tires has advanced in recent years, but there is still much room for improvement.

Means for Solving the Problems

[0004] In a first aspect, the present invention relates to a non-pneumatic tire including a radially outer circumferential band portion including a circumferential tread portion, a hub portion on the radially inner side, and a support structure including a plurality of spokes extending from the hub portion to the circumferential band portion. At least one of the plurality of spokes includes a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion, and the radially outer foot portion is mechanically connected to the radially outer circumferential band portion.

[0005] In a second aspect, the present invention relates to a non-pneumatic tire comprising a radially outer circumferential band portion including a circumferential tread portion, a radially inner hub portion, and a support structure including a plurality of spokes extending from the hub portion to the circumferential band portion. At least one of the plurality of spokes includes a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion, and at least the radially outer foot portion is removably attached to the radially outer circumferential band portion.

[0006] In a third aspect, the present invention relates to a non-pneumatic tire comprising a radially outer circumferential band portion including a tread, a radially inner hub portion, and a support structure including a plurality of spokes extending between the hub portion and the circumferential band portion. At least one of the plurality of spokes includes a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion, the spoke includes a polymer composition, and at least one of the radially inner head portion and the radially outer foot portion comprises an attachment surface at least partially formed of a material harder than the polymer composition. According to the third aspect, among the radially outer circumferential band portion and the radially inner hub portion, the portion adjacent to and in contact with the attachment surface is at least partially formed of one or more of the above material and another material harder than the polymer composition.

[0007] The present invention will be described by way of example with reference to the accompanying drawings.

Brief Description of the Drawings

[0008]

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DETAILED DESCRIPTION OF THE INVENTION

[0009] In a first aspect, the present invention relates to a non-pneumatic tire comprising a radially outer circumferential band portion including a circumferential tread portion, a radially inner (circumferential) hub portion, and a (circumferential) support structure including a plurality of spokes extending from the hub portion to the circumferential band portion. At least one of the plurality of spokes comprises a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion, and the radially outer foot portion is mechanically connected to the radially outer circumferential band portion. Thus, one or more spokes (e.g., most or all of the plurality of spokes) are connected to the radially outer circumferential band portion by a mechanical connection that allows for easy assembly and / or connection, for example. Preferably, such a connection by mechanical connection allows the spoke(s) to be removed from the circumferential band portion in the event that one or more spokes are damaged during use of the tire. Adhesives and / or co-curing of the spokes to the band portion can be avoided.

[0010] In one embodiment, the radially outer circumferential band portion includes a radially inner annular connection portion and / or the radially inner hub portion includes a radially outer annular connection portion.

[0011] In another embodiment, each of the head portion and the foot portion is mechanically connected to an adjacent portion (e.g., an annular connection portion) of each of the radially outer circumferential band portion and the radially inner hub portion. In such an embodiment, the attachment of the spokes and / or the assembly of the tire is simple and / or flexible. Optionally, one or more spokes, or most or preferably all of the plurality of spokes, are removably mechanically connected.

[0012] In yet another embodiment, one or more of the hub portion, the band portion, the radially inner annular connection portion, the radially outer annular connection portion, and the spokes comprise one or more polymer compositions. One or more of such polymer compositions can be reinforced with cords and / or fibers. Preferably, a plurality of spokes, or at least a majority of a plurality of spokes, are spokes of a cord-reinforced polymer composition such as a spoke of a cord-reinforced elastomer (e.g., rubber) composition. Optionally, the cord reinforcement can be provided as a fabric that at least partially extends along the spoke, such as radially, and includes a plurality of parallel cords. As another option, a spoke of an elastomer composition can include a member in which another material that is harder than the elastomer composition, for example, is at least partially embedded.

[0013] In yet another embodiment, the polymer composition includes one or more of an elastomer composition (e.g., a rubber composition) and a thermoplastic polymer composition (e.g., a thermoplastic elastomer such as a thermoplastic polyester elastomer).

[0014] In yet another embodiment, the spokes include one or more of an elastomer composition and a thermoplastic polymer, and one or more of the plurality of annular connection portions include one or more of a thermoplastic polymer and an elastomer composition.

[0015] In a preferred embodiment, the spokes include one or more of an elastomer composition and a thermoplastic polymer, and one or more of the plurality of annular connection portions include a thermoplastic polymer. Preferably, the spokes include an elastomer composition (such as a rubber composition), and one or more of the plurality of annular connection portions include a thermoplastic polymer.

[0016] In yet another embodiment, the spokes include an elastomer composition (e.g., a rubber composition), and one or more of the plurality of annular connection portions include an elastomer composition (e.g., a rubber composition). The two elastomer compositions may be the same or different.

[0017] In another preferred embodiment, the polymer composition is an elastomeric composition such as a rubber composition. Optionally, the elastomeric composition (such as a rubber composition) includes one or more of rubber (such as those containing one or more of natural rubber, synthetic polyisoprene, butadiene rubber, styrene-butadiene rubber, and butyl rubber), filler (such as those containing one or more of carbon black and silica), resin (such as hydrocarbon resins selected from one or more of coumarone-indene resin, petroleum hydrocarbon resin, terpene resin, styrene / alpha-methylstyrene resin, terpene phenol resin, rosin-derived resin and copolymers and / or mixtures thereof), accelerator, anti-degradant, oil, liquid diene polymer, coupling agent (such as carbon black coupling agent and / or silane), sulfur donor, and sulfur. As used herein, liquid means that the material is in a liquid state at 23 °C. The composition may be a sulfur-curable rubber composition or a sulfur-cured rubber composition. Optionally, the elastomeric composition such as a rubber composition may be fiber-reinforced.

[0018] In yet another embodiment, the elastomer composition or rubber composition comprises 100 phr of rubber including one or more of natural rubber, synthetic polyisoprene, polybutadiene rubber, and styrene-butadiene rubber. Preferably, the composition comprises at least 50 phr of natural rubber (such as 50 phr - 100 phr of natural rubber, and optionally 0 phr (or 5 phr) - 50 phr of polybutadiene rubber, etc.). Further, the elastomer composition or rubber composition preferably comprises a filler including carbon black and / or silica. For example, it is desirable that such a filler is in the range of 20 phr - 150 phr, preferably in the range of 30 phr - 90 phr. Preferably, such a filler mainly comprises carbon black. The elastomer composition or rubber composition can further comprise 1 phr - 40 phr of resin (preferably including a phenolic resin). Further, the elastomer composition or rubber composition can comprise 1 phr - 30 phr of oil, preferably 1 phr - 20 phr of oil. Finally, the elastomer composition or rubber composition can typically comprise 1 phr - 15 phr of anti-degradant, 0.5 phr - 10 phr of accelerator, 0.1 phr - 10 phr of zinc oxide, and 0.5 phr - 10 phr of sulfur. Other components can also be present.

[0019] In yet another embodiment, the spoke is cord-reinforced and / or fiber-reinforced, and one or more cords and / or fibers optionally comprise any of woven, carbon, metal, bio-based, polymer, and glass fiber materials.

[0020] In yet another embodiment, the cord and / or fiber comprises a woven material optionally selected from one or more of polyester (preferably PET), polyamide (preferably one or more of PA-6, PA-6,6 (e.g., Nylon (trademark)), aromatic polyamide / aramid), and rayon. Optionally, one or more of these materials can be recycled materials. Using hybrid materials, or cords and / or fibers of a plurality of such materials, is also an option.

[0021] In another embodiment, the cord provided herein is one or more of a single filament cord and a multifilament cord. For example, when the cord is measured after being extracted from the spoke of a tire, the (maximum) diameter measured perpendicular to the extension of the cord within the spoke may be in the range of 0.01 mm to 2 mm, preferably in the range of 0.01 mm to 1 mm.

[0022] In yet another embodiment, at least one of the radially inner head portion and the radially outer foot portion includes an anchor portion, and the anchor portion is held, engaged, and / or fixed within complementary anchor slots in respective adjacent portions of the radially outer circumferential band portion and the radially inner hub portion. Preferably, the slots extend substantially axially of the tire and / or the anchor portion is one or more of axially insertable and axially removable within the slots. In other words, the anchor portion is held by mechanical coupling within the slots, for example to prevent radial movement. The anchor portion can be described as a male portion (or male anchor portion) and the anchor slot as a female portion (or female anchor portion). Optionally, one or more of the head portion and the foot portion of the spoke can include two or more anchor portions.

[0023] In yet another embodiment, the anchor portion is: i) insertable or slidable along the axial direction, ii) held and / or fixed to prevent radial movement, preferably held and / or fixed in axially extending anchor slots at adjacent portions of the circumferential band portion on the outer radial side and the hub portion on the inner radial side respectively, and iii) includes one or more of a double-tail shaped cross-section, an H-shaped cross-section, a double-T shaped cross-section, a chevron-shaped cross-section, a polygonal-shaped cross-section, an elliptical-shaped cross-section, a circular-shaped cross-section, and a star-shaped cross-section. Such cross-sections are parallel to the equatorial plane of the tire. The above slots may be formed, for example, in the circumferential and radially inner portion or layer of the shear band of the circumferential band portion.

[0024] In yet another embodiment, the anchor portion is further press-fitted into the anchor slot in the axial direction (i.e., the first axial direction). If necessary, the spoke and / or the anchor portion can be removed or detached again in the axial direction opposite to the direction of the first axial direction, for example, by a stroke in that direction.

[0025] In another embodiment, the circumferential band portion includes one or more of a circumferential tread portion on the outer radial side, a circumferential shear band supporting the circumferential tread portion (optionally including a plurality of circumferential rubber composition layers), and an inner radial annular connection portion disposed on the inner radial side of the tread portion and / or the shear band. Preferably, the inner radial annular connection portion can be provided with the anchor slot along the circumferential direction of the annular connection portion. Optionally, the annular connection portion includes one or more of a circumferentially closed ring, a plurality of polymer composition members (such as blocks) arranged circumferentially. Optionally, each polymer composition member is provided with one or more anchor slots for accommodating the anchor portion of the spoke. The annular connection portion and / or its members can be co-cured or attached to the tread portion and / or the shear band via an adhesive. One or more layers of the shear band can be cord-reinforced using, for example, the cord material already described above in relation to spoke reinforcement.

[0026] In yet another embodiment, one or more of the plurality of components, members or parts referred to herein (e.g., one or more of the circumferential band portion, circumferential tread portion, circumferential shear band, radially inner annular connection portion, radially outer annular connection portion, and hub portion) are integrally formed, adhered, cured, and co-cured with each other. Such molding and / or connection techniques themselves are known to those skilled in the art. For example, a plurality of components, members or parts including uncured and / or cured elastomer compositions or rubber compositions can be attached together and co-cured. Preferably, they are sulfur-cured with each other. Another option is peroxide curing. Additionally, or alternatively, uncured rubber, primer or dip (such as RFL systems), and / or adhesives can be used to improve the connection between such components, members, or parts. Suitable adhesives are also commercially available and known to those skilled in the art. These adhesives can be selected considering the components and / or compositions to be joined together. For example, the adhesives include one or more of rubber-based, silicone-based, isocyanate-based, acrylate-based, epoxide-based, polyurethane-based adhesives. Optionally, a curing cement such as used in tire retreading can be used to co-cure an elastomer composition portion to an already cured elastomer composition portion. It is also possible to use a green rubber layer for co-curing. Optionally, one or more functional polymers can be used in one or more of the elastomer compositions to support co-curing. Such functional groups can include, but are not limited to, one or more of isocyanate groups, hydroxide groups, halide groups, amine groups, amide groups, carboxylic acid groups, epoxide groups, acrylate groups, peroxide groups, and other suitable groups.

[0027] In yet another embodiment, the axially extending slot and the anchor portion taper along the axial direction. Due to such tapering, the anchor portion can be inserted into the slot only in one axial direction. In other words, when inserted into the slot, it is fixed against movement in the opposite direction (and radial movement). Preferably, the anchor slot includes two opposing circumferentially extending flange portions that hold, fix, and / or engage the anchor portion to prevent radial movement.

[0028] In yet another embodiment, the anchor portion of the spoke head portion (adjacent to the hub portion and / or the annular connection portion radially outside the hub portion) extends axially and includes two adjacent segments that taper in opposite axial directions. Preferably, the anchor portion of the head portion tapers from the axial center portion of the head portion towards both outer ends in the axial direction. Such a design including two portions or segments that taper in two opposite directions enables a high degree of fixation of the spoke at the hub portion and / or its annular connection portion. Preferably, the hub portion and / or its annular connection portion comprise two annular connection portions that are axially attachable to each other, and / or each comprises an anchor slot for complementarily accommodating one of the tapered segments of the spoke head portion. The two annular connection portions hold and / or clamp the anchor portion of the head portion of the hub portion (e.g., by flange portions) to prevent movement in any direction (particularly to prevent axial and / or radial movement).

[0029] In yet another embodiment, a plurality of adjacent spokes include (respective) anchor portions retained within respective axially extending slots at respective adjacent portions of a radially outer circumferential band portion and a radially inner hub portion. Optionally, at least one of these slots tapers in a first axial direction and at least another one of these slots tapers in a second axial direction. Optionally, the axial directions of the slots alternate over at least a circumferential sector of the support structure. Such an arrangement means that separate spokes are inserted from separate axial directions. After partially or fully assembling the spokes of the tire, it is not possible to remove all the spokes together in one axial direction. This provides a stable tire that can be efficiently manufactured.

[0030] In yet another embodiment, one or more of the plurality of spokes comprise or have one or more cross-sections selected from an X-shape, a V-shape, a C-shape, an I-shape, an H-shape, an O-shape, an S-shape, a Y-shape, a semi-X shape, and one or more curved and twisted shapes / morphologies of one or more of the aforementioned shapes in a plane parallel to the equatorial plane of the tire. Preferably, the shape is an I-shape. Another preferred shape is a semi-X shape (particularly corresponding to an X-shape cut substantially radially). Also, such a shape can include an angled bracket shape, in which case the bent portion is not necessarily at the radial center of the shape.

[0031] In yet another embodiment, the anchor portion is an axially extending and tapered elongated rail, and the complementary anchor slot is optionally an axially extending and tapered elongated slot. Also in this case, the anchor portion is preferably retained and / or fixed in the slot to prevent radial movement. Such rail and / or slot shapes allow the anchor portion to be easily, surely, and stably attached to the respective complementary anchor slot.

[0032] In yet another embodiment, the spoke further comprises a circumferentially protruding support portion that contacts either the radially inner surface of the circumferential band portion on the radially outer side (e.g., the radially inner surface or side surface of the annular connection portion on the radially inner side) and the radially outer surface of the hub portion on the radially inner side (e.g., the radially outer surface of the annular connection portion on the radially outer side). In other words, the protruding portion further supports the spoke to prevent radial movement.

[0033] In yet another embodiment, the spoke has a first side surface and a second side surface in the circumferential direction, and the support portion extends further toward the radially central portion of the spoke on one of the first side surface and the second side surface (e.g., only one of them) than on the other of the first side surface and the second side surface. Such a feature helps to give the spoke a preferred bending direction (e.g., when a load such as a radial load is applied to the tire and / or the spoke).

[0034] In yet another embodiment, the spoke has a first support portion that contacts the radially inner surface of the circumferential band portion on the radially outer side and a second support portion that contacts the radially outer surface of the hub portion on the radially inner side. Optionally, both the first and second support portions extend further toward the center or central portion in the radial direction of the spoke on one of the circumferential side surfaces of the spoke than on the opposite side surface in the circumferential direction of the spoke.

[0035] In yet another embodiment, the spoke comprises a rib or strut portion that extends from its head portion to its foot portion. Optionally, such a portion includes a substantially straight, bent, or curved plane or wall that extends from the head portion to the foot portion.

[0036] In yet another embodiment, the foot portion and the head portion each extend axially by at least 20% or more (optionally, at least 40% or more, or at least 70% or more) of the maximum axial width of the circumferential band portion.

[0037] The features of the embodiments mentioned herein are emphasized to be applicable, if necessary, to the support structure and / or a plurality of spokes of the tire, a majority of the plurality of spokes, or all of the spokes. This is particularly applicable to the further aspects and their embodiments mentioned in this specification.

[0038] In a second aspect, the non-pneumatic tire comprises a radially outer circumferential band portion including a circumferential tread portion, a radially inner (circumferential) hub portion, and a (circumferential) support structure including a plurality of spokes extending from the hub portion to the circumferential band portion. At least one of the plurality of spokes comprises a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion, and at least the radially outer foot portion is removably attached to the radially outer circumferential band portion. For example, the spoke need not be or is not attached to the radially outer circumferential band portion via an adhesive and / or co-curing. The features of the present invention enable one or more stable and easy assemblies, and also enable the spoke to be removed from the circumferential band portion for purposes of modification, etc.

[0039] In one embodiment, the spoke is removably attached to the radially inner hub portion and the radially outer band portion (and / or, for example, one of each annular connection as described above in this specification). Thus, an individual spoke (e.g., each spoke) is removable at both its radial ends and can be completely removed. For example, when a spoke is damaged during use of the tire, the individual spoke can be replaced with another spoke.

[0040] In another embodiment, the spoke is removably attached by one or more of a screw connection, a surface fastener connection, and a mechanical coupling.

[0041] In another embodiment, the head portion on the radially inner side and the foot portion on the radially outer side of each of the majority or all of the spokes are removably attached by mechanical connection to the respective adjacent portions (e.g., annular connection portions) of the circumferential band portion on the radially outer side and the hub portion on the radially inner side. In particular, such mechanical connection can be provided as described in other embodiments of this specification.

[0042] In a third aspect, the non-pneumatic tire comprises a circumferential band portion on the radially outer side including a circumferential tread portion, a hub portion on the radially inner side (circumferential), and a (circumferential) support structure including a plurality of spokes extending between the hub portion and the circumferential band portion. At least one of the plurality of spokes comprises a head portion on the radially inner side adjacent to the hub portion and a foot portion on the radially outer side adjacent to the circumferential band portion, the spoke comprises a polymer composition, and at least one of the head portion on the radially inner side and the foot portion on the radially outer side comprises an attachment surface at least partially formed of a material harder than the polymer composition. According to a further third aspect, among the circumferential band portion on the radially outer side and the hub portion on the radially inner side, the portion (e.g., annular connection portion) adjacent to and in contact with the attachment surface is at least partially formed of or includes one or more of another material harder than the above material and the polymer composition. By using such a harder material, the joint between the spoke and the adjacent connection portion is strengthened, and the connection between the spoke and the adjacent band portion and / or hub portion is made more durable.

[0043] In one embodiment, the above material and / or the other material is at least 5%, preferably at least 50%, or more preferably at least 100% harder than the polymer composition. For example, a first hardness value can be determined for the polymer composition, and a second hardness value can be determined for the above material or the other material. Being at least 5% harder means that the second hardness value is at least 5% higher than the first hardness value. In this specification, hardness can be measured as shore hardness in accordance with ASTM D2240 or equivalent standards. For example, in a metal plate, it should be noted that the use of one or more metals such as aluminum, iron, brass, copper, and steel falls within these respective ranges when compared to the hardness of the elastomer composition and / or the hardness of the thermoplastic polymer or thermoplastic polymer composition.

[0044] In one embodiment, at least one of the radially inner head portion and the radially outer foot portion including the mounting surface is connected and / or fixed by a mechanical connection (in other words, a form fit) to a portion (such as an annular connection portion) that is in contact adjacent to the mounting surfaces of the radially outer circumferential band portion and the radially inner hub portion.

[0045] In another embodiment, the mounting surface includes a first rail including the above material, and optionally, a portion (such as an annular connection portion) adjacent to and in contact with the mounting surface includes a second rail including one or more of the above material and the other material. The second rail preferably holds (or fixes) the first rail complementarily to prevent radial movement. In particular, one of the first rail and the second rail is adapted to axially (and optionally slidably) accommodate the other of the first rail and the second rail.

[0046] In another embodiment, the spoke is a spoke of an elastomer composition, preferably a spoke of a rubber composition, and / or one or more of the above material and the other material are selected from one or more of a thermoplastic polymer, ceramics, and metals.

[0047] In yet another embodiment, the mounting surface includes at least one metal plate.

[0048] In yet another embodiment, the spoke comprises two bent metal plates, each metal plate forming an axially extending rail, optionally having an L-shaped cross-section. Optionally, a plurality of cords (preferably extending transversely to the rails) are sandwiched between and / or partially surrounded by both metal plates. Preferably, the plurality of cords extend through and / or are coated by an elastomeric composition.

[0049] In yet another embodiment, the plurality of metal plates are adhered and / or co-cured to the elastomeric composition of the spoke.

[0050] In yet another embodiment, the spoke comprises an elastomeric composition and the metal plate is at least partially embedded in and / or cured by the elastomeric composition.

[0051] In yet another embodiment, each of the first rail and the second rail tapers along the axial direction. Optionally, the first rail and the second rail allow axial movement of the first rail relative to the second rail.

[0052] In yet another embodiment, one or both of the annular connections may each be an integral ring. Alternatively, one or both of the annular connections can be formed by a plurality of blocks or circumferential segments, and one or more of these blocks or circumferential segments are co-cured together and adhered to each other via an adhesive.

[0053] FIG. 1 is a schematic perspective view of a tire 100 including a circumferential band portion 110 on the radially outer side, a circumferential hub portion 160 on the radially inner side, and a (circumferential) support structure 140 that supports the circumferential band portion 110 on the circumferential hub portion 160. The circumferential band portion 110 includes a circumferential (and radially outer) tread band portion 111. The support structure 140 includes a plurality of spokes 130 between the hub portion 160 and the circumferential band portion 110. FIG. 2 shows the connection of the spoke 130 to the hub portion 160 and the circumferential band portion 110 on the radially outer side in more detail.

[0054] The schematic cross-sectional view of FIG. 2 (parallel to the equatorial plane of the tire, or parallel to the circumferential center line of the tire, or an equivalent cross-section) shows the extension and / or connection of the plurality of spokes 130 of the connection structure 140 between the radially outer side of the hub portion 160 and / or the circumferential annular connection portion 164 and the radially inner annular connection portion 114 of the circumferential band portion 110. The circumferential band portion 110 includes a tread band portion 111 and a circumferential connection portion 114 on the radially inner side. Although not explicitly shown in this specification, the tread band portion 111 may include a circumferential tread portion on the radially outer side adjacent to the annular connection portion 114 and / or a circumferential shear band on the radially inner side as required.

[0055] As shown in FIG. 2, each spoke 130 is mechanically connected at the circumferential band portion 110 on the radially outer side, particularly at its circumferential annular connection portion 114. Further, according to this non-limiting embodiment, each spoke 130 is also mechanically connected to the annular connection portion 164 on the radially outer side of the hub portion 160. Each radially end of the spoke 130 includes an anchor portion that engages with the anchor slots of the respective annular connection portions 114, 164. Further, each spoke 130 is schematically shown together with a cord reinforcing material extending from one end of the spoke 130 to the radially opposite end.

[0056] In a plurality of embodiments and / or figures of this specification, for the sake of easier understanding of directions, a circumferential direction c, an axial direction a, and a radial direction r are shown. The circumferential direction c is perpendicular to the axial direction a. The same applies to the radial direction r. The axial direction a is parallel to the rotation axis of the tire. The directions referred to in this specification are not necessarily limited to a specific orientation of a given direction unless otherwise described in this specification.

[0057] FIG. 3 shows a partial perspective view of the support structure 140 and the circumferential band portion 110 (excluding the annular connection portion of the hub portion), appropriately using the same reference numerals as in FIGS. 1 and 2. Each spoke 130 has a radially inner head portion 136 and a radially outer foot portion 137. The radially inner head portion 136 and the radially outer foot portion 137 are connected by a rib portion 131 that extends substantially in the radial and axial directions. On the other hand, the plurality of radially outer foot portions 137 include a plurality of anchor portions 135, and the anchor portions 135 are axially inserted into corresponding anchor slots 113 formed as axially extending slots in the annular connection portion 114 and held (or fixed). On the other hand, the plurality of radially inner head portions 136 include a plurality of anchor portions 134 that can be inserted into corresponding anchor slots formed in a corresponding annular connection portion of the hub portion (not explicitly shown in FIG. 3). In this embodiment, the anchor portions 134 and 135 each have a T-shaped cross section and hold the spoke 130 so as not to move radially from the corresponding anchor slot 113 by mechanical connection. However, the anchor portions 134 and 135 can also have other cross-sectional shapes, for example, one or more of a double-tail shape cross section, an H shape cross section, a double-T shape cross section, a V shape cross section, a polygonal shape cross section, an elliptical shape cross section, a circular shape cross section, a star shape cross section. Usually, such cross sections engage with corresponding anchor slots or slots that hold and / or fix the anchor portions, particularly to prevent radial movement from their respective anchor slots.

[0058] Figure 4 shows another preferred embodiment of the circumferential band portion on the radially outer side or the annular connection portion 114' of the circumferential band portion on the radially outer side. The illustrated annular connection portion 114' includes a plurality of anchor slots 113', 113'' (or, in other words, rails) that extend substantially axially. In this particular embodiment, the slots 113', 113'' taper along the axial direction. In particular, the tapered axial directions alternate circumferentially from slot 113' to slot 113''. Accordingly, the corresponding spokes can be attached and / or removed in different (i.e., opposite) axial directions from one slot 113' to the next circumferentially adjacent slot 113'' along the circumferential direction.

[0059] An embodiment of a spoke 230 that can be inserted into the slots 113', 113'' according to FIG. 4 is shown in the perspective view of FIG. 5. The spoke 230 includes a foot portion 237 and a head portion 236, and ribs or strut portions 231 extend between those portions (and axially when attached to the tire). Further, the foot portion 237 includes a T-shaped anchor portion 235 and a support portion 238 that can support the spoke 230 on an adjacent annular connection portion of the circumferential band portion on the radially outer side of the tire. For the sake of explanation only, the foot portion 237 is referred to as the foot portion in this specification because it can be considered to be close to the footprint area of the tire, if any, when in the lowest vertical position during rotation of the tire. The head portion 236 also includes a substantially T-shaped anchor portion 234 and a support portion 239 that can support the spoke 230 on an adjacent annular connection portion of the hub portion. In this embodiment, the anchor portion 234 includes two segments 232, 233 that extend axially and are tapered in opposite axial directions. In other words, the anchor portion 234 tapers from the axial center portion towards both axial ends. Such a design including two tapered portions or segments 232, 233 in opposite directions enables a high degree of fixation of the spoke at the hub portion.

[0060] A corresponding example of fixing the spoke 230 to the hub portion 260 is shown in FIG. 6. In particular, the radially inner portion of the spoke 230 is shown in contact with two members of the hub portion 260. The illustrated cross-section extends perpendicular to the circumferential direction and partially shows the spoke 230 and its rib portion 231 and a part of the hub portion 260 extending in the axial and radial directions. In the present embodiment, the hub portion 260 includes a first annular member or annular portion 264 and a second annular member or annular portion 265, and fixes the spoke 230 to prevent axial movement by two flanges 266 and 267, respectively. For example, when attaching the spoke 230, with the other of the first annular portion 264 and the second annular portion 265 absent, the spoke 230 is axially inserted into one of the first annular portion 264 and the second annular portion 265, and then the other of the first annular portion 264 and the second annular portion 265 can be attached and fixed. As shown in FIG. 6, the first annular portion 264 and the second annular portion 265 can be attached to the circumferential plate portion 268 of the hub portion 260. Also, for example, in order to simplify the attachment or assembly process, it is also possible to integrally form the plate portion 268 with either the first annular portion 264 or the second annular portion 265. A T-shaped anchor portion 234 having two axially tapered segments 232 and 233 in opposite axial directions is held by the first annular portion 264 and the second annular portion 265 to prevent axial movement. The spoke 230 is further held by complementary-shaped slots in the two annular portions 264 and 265 to prevent radial and circumferential movement.

[0061] FIG. 7 shows another embodiment of a spoke 330 similar to the spoke 230 already shown in FIG. 5. Thus, the spoke 330 also has a foot portion 337 and a head portion 336 connected by a strut or rib portion 331. The foot portion 337 has an axially tapered anchor portion 335, and the head portion 336 includes an axially extending anchor portion 334 having substantially the same shape and / or cross-section as that described in the previous embodiment. Thus, the anchor portion 334 has two anchor segments 332 and 333 that taper in opposite directions. Also, the anchor portion 334 preferably includes a cord reinforcement 34 that extends substantially axially through a portion thereof. Similar to the previous embodiment, the spoke 330 has two support portions 338 and 339 for supporting the spoke 330 on respective adjacent surfaces of an annular connection portion that houses the spoke 330. Further, the spoke 330 of the present embodiment includes a foot portion 337 that includes a partially embedded member 35 that forms the axially tapered anchor portion 335 of the spoke 330. In particular, this member 35 is composed of a material that is harder than the polymer composition included in other parts of the spoke, such as the rib portion 331. In particular, in the present example, a spoke including a rubber composition is shown, but the embedded member 35 preferably includes a thermoplastic polymer that is at least 5% harder than the rubber composition. For example, the thermoplastic polymer is a thermoplastic polyester elastomer. The member 35 can be co-cured and / or adhered with an adhesive so as to be partially embedded within the spoke 330. Optionally, additional protrusions extending into the polymer composition of the spoke can also be provided (not shown) to further improve adhesion.

[0062] Figure 8 shows yet another embodiment of a suitable spoke 430. This spoke 430 includes a foot portion 437, a head portion 436, and a rib portion 441, similar to the previous embodiments. The foot portion 437 includes a partially embedded member 45 that defines the T-shaped connection portion 435. The foot portion 437 further includes a support portion 438, and the head portion 436 also has a support portion 439 with a T-shaped connection portion 434. Further, the spoke 430 includes a plurality of cords or fabrics 41 (optionally coated with a rubber composition) that extend substantially from the connection portion 434 of the head portion 436 through the rib portion 441 to the connection portion 435 of the foot portion 437. In other words, when the spoke 430 is attached to the tire, the plurality of cords or the fabric including the plurality of cords 41 extends substantially radially within the support structure. Also, the plurality of cords or fabric 41 can be described as being sandwiched between two circumferentially opposing portions of the connection portion 435 and / or the member 45. Preferably, the partially embedded member 45 includes a thermoplastic polymer that is at least 5% harder than the rubber composition of the spoke 430, for example, in one or more of its strut portions 441 and / or support portions 438, 439.

[0063] Figure 9 shows yet another embodiment of the present invention, where the spoke 530 includes two angled metal plates 55 that partially define the outer attachment surface of the T-shaped anchor portion 535 in the foot portion 537 of the spoke 530. The metal plates 55 are embedded and particularly cured in a rubber composition that forms the spoke 530 (including, for example, its rib portion 531, support portion 539, and the polygonal connection portion 534 of its head portion 536). Note that the rib portion 531 has a curved shape in this embodiment that gives the spoke 530 a preferred and / or defined bending direction (e.g., bent and / or facing the circumferential direction) under radial loads and the like. This is particularly useful when providing a plurality of circumferentially adjacent spokes to the tire, and preferably they have substantially the same curved shape and / or face the same direction.

[0064] FIG. 10 shows an embodiment of a radially outer circumferential band portion 510 suitable for accommodating the anchor portion 535 of the spoke 530 shown in FIG. 9 (reduced view). The circumferential band portion 510 includes a tread band 511 and a radially inner annular connection portion 514 having a plurality of slots 513 (extending axially and alternately tapered along the circumferential direction), and these slots 513 are provided with a plurality of metal plates 512 at least partially, and contact an attachment surface formed by a plurality of metal plates 55 of the spoke 530 shown in FIG. 9. The plurality of metal plates (preferably at least partially embedded, such as cured with an elastomer or rubber composition material of the spoke 530 and / or the annular connection portion 514) provide a very strong and durable connection between the plurality of spokes and their respective annular connection portions. Further, the feasibility and / or reliability of attaching and detaching the spokes are further improved.

[0065] FIG. 11 shows another option of providing a plurality of metal plates in the annular connection portion of the radially outer circumferential band portion. The illustrated metal rail 642 has two interconnected metal plate members 62, 63, and a slot or rail that tapers (axially) is formed therebetween. The two metal plate members 62, 63 are firmly connected by a metal connection bar or member 65. This embodiment further improves the durability and / or reliability of the connection between the spoke and the corresponding tapered slot. Also, a defined distance is provided between the two metal plate members 62, 63. For example, in order to reinforce the slot having a structure as shown in FIG. 10, the metal rail 642 can be used instead of the aforementioned separate metal plates 512.

[0066] FIG. 12 shows another embodiment and / or aspect of the present invention, where the spoke 730 has a foot portion 737 and a head portion 736. The head portion 736 further includes an anchor portion 734 that holds and / or fixes the spoke 730 in an axially extending anchor slot in a complementary shape to the connection portion 764 of the hub portion. The foot portion 737 includes an anchor portion 735 that holds and / or fixes the spoke 730 in an axially extending anchor slot in a complementary shape to the radially outer band portion 714. The head portion 736 and the foot portion 737 are connected (e.g., radially) by a strut portion or rib portion 731. In this embodiment, the spoke 730 includes two circumferentially asymmetric support portions 738, 739. The support portion 738 of the foot portion 737 of the spoke extends radially further away from the adjacent band portion 714 on the first circumferential side surface cs' of the spoke 730 than in the case of the second portion 738'' of the support portion 738 on the second circumferential side surface cs'' of the spoke 730 at the first portion 738' of the support portion 738. Similarly, in the head portion 736, the support portion 739 extends radially further away from the surface of the adjacent hub portion 764 at the first portion 739' on the first circumferential side surface cs' than in the case of the second portion 739'' on the second circumferential side surface cs'', resulting in a predetermined and / or defined bending direction of the spoke 730 that receives a radial load.

[0067] Although not explicitly shown herein, another embodiment includes a plurality of circumferential spoke rows arranged axially, such as two rows, three rows, or four rows. For each row, the circumferential positions of such spokes may be the same or may be offset circumferentially.

[0068] The above-described embodiments include a plurality of tapered anchor portions and / or a plurality of corresponding slots. These tapered shapes are preferred embodiments of the present invention, but it is emphasized that these do not constitute the essential features of the present invention. Further, some embodiments include anchor portions having a double taper, but it is also possible to provide portions having a taper in only one direction.

[0069] The above-described aspects, embodiments, and their features can be combined with each other.

[0070] In summary, one or more of the present invention and / or its embodiments are useful for reducing the complexity of manufacturing a non-pneumatic tire. The number of steps of co-curing, curing, and adhesion during or after tire assembly can be reduced. The spokes are pre-manufactured and can be easily attached. Mechanical connection facilitates the insertion and replacement of the support structure and spokes. By providing a hard material such as metal in the anchor portion and slots, the robustness and / or durability of the tire can be further improved.

[0071] In light of the description of the invention set forth herein, variations of the present invention are possible. For the purpose of describing the invention in question, specific representative embodiments and details have been shown, but it will be apparent to those skilled in the art that various changes and modifications can be made without departing from the scope of the invention in question. Therefore, it should be understood that in the foregoing specific embodiments, changes can be made within the entire scope of the subject matter of the present invention as defined by the following appended claims.

Claims

1. A non-pneumatic tire, a radially outer circumferential band portion including a circumferential tread portion; a radially inner hub portion; a support structure including a plurality of spokes extending from the hub portion to the circumferential band portion; At least one spoke of the plurality of spokes includes a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion; A non-pneumatic tire, wherein the radially outer foot portion is mechanically coupled to the radially outer circumferential band portion.

2. the radially outer circumferential band portion having a radially inner annular connection portion and the radially inner hub portion having a radially outer annular connection portion; 2. The non-pneumatic tire of claim 1, wherein each of said head and foot portions is mechanically coupled with adjacent annular connections of said radially outer circumferential band portion and said radially inner hub portion, respectively.

3. The non-pneumatic tire of claim 2 , wherein each of the annular connector and spokes comprises one or more polymer compositions.

4. The non-pneumatic tire of claim 3 , wherein the polymer composition comprises one or more of an elastomeric composition and a thermoplastic polymer composition.

5. 2. The non-pneumatic tire of claim 1, wherein at least one of the radially inner head portion and the radially outer foot portion includes an anchor portion retained in a complementary anchor slot of the respective adjacent portion of the radially outer circumferential band portion and the radially inner hub portion.

6. 6. The non-pneumatic tire of claim 5, wherein the anchor portions are one or more of: i) inserted axially; ii) held against radial movement in axially extending anchor slots in adjacent portions of the radially outer circumferential band portion and the radially inner hub portion; and iii) include one of a dovetail-shaped cross-section, an H-shaped cross-section, a double T-shaped cross-section, a chevron-shaped cross-section, a polygon-shaped cross-section, an elliptical cross-section, a circular cross-section, and a star-shaped cross-section.

7. The non-pneumatic tire of claim 5 , wherein the anchor slot and the anchor portion are axially tapered.

8. 6. The non-pneumatic tire of claim 5, wherein a plurality of adjacent spokes include anchor portions retained in respective axially extending anchor slots in the respective adjacent portions of the radially outer circumferential band portion and the radially inner hub portion, at least one anchor slot tapering in a first axial direction and at least one other anchor slot tapering in a second axial direction.

9. 6. The non-pneumatic tire of claim 5, wherein said anchor portion is an axially extending, elongated, tapered rail and said complementary anchor slot is an axially extending, elongated, tapered slot.

10. 6. The non-pneumatic tire of claim 5, wherein said spokes include circumferentially projecting supports contacting one of a radially inner surface of said radially outer circumferential band portion and a radially outer surface of said radially inner hub portion.

11. 11. The non-pneumatic tire of claim 10, wherein the spoke has a first side and a second side in a circumferential direction, and the support portion extends further toward a radial center of the spoke on one of the first side and the second side than the other of the first side and the second side.

12. The non-pneumatic tire of claim 1 , wherein said foot portion and said head portion each extend axially beyond at least 20% of a maximum axial width of said circumferential band portion.

13. A non-pneumatic tire, a radially outer circumferential band portion including a circumferential tread portion; a radially inner hub portion; a support structure including a plurality of spokes extending from the hub portion to the circumferential band portion; At least one spoke of the plurality of spokes includes a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion; A non-pneumatic tire, wherein at least said radially outer foot portion is removably attached to said radially outer circumferential band portion.

14. 14. The non-pneumatic tire of claim 13, wherein said spokes are removably attached to said radially inner hub portion and said radially outer circumferential band portion.

15. 14. The non-pneumatic tire of claim 13, wherein a radially inner head portion and a radially outer foot portion of each of said spokes of said non-pneumatic tire are removably attached to adjacent portions of said radially outer circumferential band portion and said radially inner hub portion, respectively, by a mechanical connection.

16. A non-pneumatic tire, a radially outer circumferential band portion including a circumferential tread portion; a radially inner hub portion; a support structure including a plurality of spokes extending between the hub portion and the circumferential band portion; At least one spoke of the plurality of spokes includes a radially inner head portion adjacent to the hub portion and a radially outer foot portion adjacent to the circumferential band portion; the spokes comprise a polymeric composition; at least one of the radially inner head portion and the radially outer foot portion includes a mounting surface formed at least in part from a material harder than the polymer composition; a radially outer circumferential band portion and a radially inner hub portion adjacent and in contact with the mounting surface, the radially outer circumferential band portion and the radially inner hub portion being at least partially formed from one or more of the material and another material harder than the polymer composition.

17. 17. The non-pneumatic tire of claim 16, wherein the mounting surface comprises a first rail comprising the material and an adjacent and contacting portion of the mounting surface comprises a second rail comprising one or more of the material and the other material, the second rail securing the first rail against radial movement.

18. 17. The non-pneumatic tire of claim 16, wherein the mounting surface comprises at least one metal plate.

19. 20. The non-pneumatic tire of claim 18, wherein said spokes comprise an elastomeric composition and said metal plates are at least partially embedded in said elastomeric composition.

20. 20. The non-pneumatic tire of claim 17, wherein each of the first rail and the second rail is tapered along an axial direction, the first rail and the second rail permitting axial movement of the first rail relative to the second rail.

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