Airless tire assembly and airless tire

Abstract

[Problem] To provide an airless tire exhibiting load bearing properties, cushioning properties, vibration damping properties and silencing properties. [Solution] An airless tire assembly according to the present disclosure comprises a support part and a cushioning part. The support part is formed in an annular shape, includes a first edge part and a second edge part along the circumferential direction of the annular shape, is flexible and unshrinkable, and is positioned so as to be in close contact with the inner surface of a tread part of a tire cover. The cushioning part includes: a first cushioning part extending from the first edge part toward a first end part and a second cushioning part extending from the second edge part toward a second end part over the entire circumference of the annular shape. The first cushioning part has a third end part displaceably positioned further to the outer side than the first end part. in the radial direction of a wheel. The second cushioning part has a fourth end part displaceably positioned further to the outer side than the second end part in the radial direction of the wheel.

Description

Assembly for airless tire and airless tire

[0001] The present disclosure relates to airless tires.

[0002] The airless tire described in Patent Document 1 includes a wheel portion, an outer ring portion, and an elastic connecting member that connects the wheel portion and the outer ring portion. In order to achieve both improved ride comfort and maintaining vehicle posture, the airless tire adjusts the relationship between the amount of tire deflection and the load acting on the wheel portion.

[0003] Japanese Patent Application Laid-Open No. 2022-171113

[0004] In the airless tire, the outer ring portion and the wheel portion are connected, so when the vehicle runs on an uneven road surface, vibrations and noise are transmitted to the vehicle body via the tire. Therefore, there is room for improvement in the quietness of the airless tire.

[0005] The present disclosure provides a technology that makes it possible to realize an airless tire that has load-bearing performance, cushioning performance, vibration-damping performance, and quietness.

[0006] One aspect of the present disclosure is an assembly for an airless tire configured to be disposed around the entire circumferential direction of the tire cover inside the tire cover, the tire cover having first and second ends and an inextensible structure that are attached to the rim of a tire wheel. The assembly includes a support portion and a buffer portion. The support portion is formed in a circular ring shape, has first and second edge portions along the circumferential direction of the circular ring shape, is non-contractile and flexible, and is disposed so as to closely contact the inner surface of the tread portion of the tire cover. The buffer portion is elastic and flexible, and is disposed so as to closely contact the inner surface of the side portion of the tire cover. The support portion and the buffer portion may be integral or separate members. The buffer portion includes a first buffer portion and a second buffer portion. The first buffer portion extends from the first edge portion toward the first end around the entire circumference of the circular ring shape. The second buffer portion extends from the second edge portion toward the second end. The first buffer portion has a third end portion that is positioned radially outward of the wheel and displaceable relative to the first end portion, and the second buffer portion has a fourth end portion that is positioned radially outward of the wheel and displaceable relative to the second end portion.

[0007] In the above-mentioned assembly, the support portion is positioned in close contact with the inner surface of the tread portion of the tire cover, thereby maintaining the arch structure of the tire. Consequently, there are no struts connecting the support portion to the wheel, and the support portion can efficiently support static and dynamic loads applied to the tire even if the tire cover is not filled with compressed air. Furthermore, the absence of struts can reduce vibrations and noise transmitted to the vehicle body via the tire.

[0008] In addition, in the above-mentioned assembly, the first and second buffer parts, which have elasticity and flexibility, push the side parts of the tire cover in the width direction of the tire, thereby pressing the first and second ends against the rim, preventing the tire cover from coming off the rim. Furthermore, when a load is applied to the tire and the support member is bent, the elastic force of the first and second buffer parts helps the support part to return to its original shape, and the tire returns to its original shape.

[0009] Therefore, an airless tire having load-bearing performance, shock-absorbing performance, vibration-damping performance, and quietness can be realized.

[0010] Another aspect of the present disclosure is an airless tire including a tire cover having first and second ends attached to a wheel rim and being inextensible, and an assembly for an airless tire configured to be disposed around the entire circumferential direction of the tire cover. The assembly includes a support portion and a buffer portion. The support portion is formed in a circular ring shape, has first and second edge portions along the circumferential direction of the circular ring shape, is incontractible and flexible, and is disposed so as to closely contact the inner surface of the tread portion of the tire cover. The buffer portion is elastic and flexible, and is disposed so as to closely contact the inner surface of the side portion of the tire cover. The support portion and the buffer portion may be integral or separate members. The buffer portion includes a first buffer portion and a second buffer portion. The first buffer portion extends from the first edge portion toward the first end around the entire circumference of the circular ring shape. The second buffer portion extends from the second edge portion toward the second end. The first buffer portion has a third end portion that is positioned radially outward of the wheel and displaceable relative to the first end portion, and the second buffer portion has a fourth end portion that is positioned radially outward of the wheel and displaceable relative to the second end portion.

[0011] The airless tire described above provides the same effects as an airless tire in which the assembly described above is attached to a tire cover.

[0012] FIG. 2A is a diagram showing the outline of a first airless tire according to a first example of the first embodiment. FIG. 2B is a diagram showing the assembly before being attached to a tire cover according to the first example of the first embodiment. FIG. 2C is a diagram showing the tire cover according to the first example of the first embodiment assembled to a wheel, as viewed from the arrows IIC-IIC in FIG. 1. FIG. 2C is a diagram showing a state in which a load is applied to the first airless tire according to the first example of the first embodiment. FIG. 3A is a diagram shown as viewed from the arrows IIIB-IIIB in FIG. 3A. FIG. 3A is a diagram shown as viewed from the arrows IIIC-IIIC in FIG. 3A. FIG. 4A is a diagram showing the assembly attached to a tire cover according to a second example of the first embodiment. FIG. 4B is an enlarged view of a portion of FIG. 4A. FIG. 4A is a diagram shown as viewed from the arrows V-V in FIGS. 4A and 4B. FIG. 6A is a plan view of an assembly according to the second example of the first embodiment. FIG. 6B is a diagram shown as viewed from the arrows VIB-VIB in FIG. 6A. FIG. 6A is a view taken along arrows VIII-VII of FIG. 6A. FIG. 9A is a view showing an assembly attached to a tire cover according to a third example of the first embodiment. FIG. 9A is an enlarged view of a portion of FIG. 8. FIG. 9B is a view taken along arrows IXB-IXB of FIGS. 8 and 9A. FIG. 9C is a view showing a compression coil spring before and after being attached to a tire cover according to a third example of the first embodiment. FIG. 10A is an enlarged view of another portion of FIG. 8. FIG. 10B is a view taken along arrows XB-XB of FIGS. 8 and 10A. FIG. 10C is a view showing a continuous crank leaf spring before and after being attached to a tire cover according to a third example of the first embodiment. FIG. 12A is an enlarged view of a portion of FIG. 11. FIG. 12B is a view taken along arrows XIIB-XIIB of FIGS. 11 and 12A. FIG. 12C is a view showing a portion of a first compression coil spring according to a fourth example of the first embodiment, in third angle projection. Fig. 13A is an enlarged view of another portion of Fig. 11. Fig. 13B is a view taken along arrows XIIIB-XIIIB in Fig. 11 and Fig. 13A. Fig. 13C is a view showing a portion of a second compression coil spring according to a fourth example of the first embodiment, using third angle projection. Fig. 14A is a view showing the appearance of a pneumatic tire according to a first reference example. Fig. 14B is a view taken along arrows XIVB-XIVB in Fig. 14A.14C is an enlarged view of the portion surrounded by the dashed line in FIG. 14B. FIG. 14C is a view showing an assembly attached to a tire cover of a second airless tire according to a first example of the second embodiment. FIG. 14D is a view showing a state in which an assembly is attached to a tire cover of a second airless tire according to a first example of the second embodiment and the tire cover is assembled to a wheel. FIG. 14E is a view taken along arrows XVIIB-XVIIB of FIG. 17A. FIG. 17F is a view taken along arrows XVIIC-XVIIC of FIG. 17A. FIG. 17G is a view taken along arrows XVIID-XVIID of FIG. 17A. FIG. 17H is a view taken along arrows XVII-XXI of FIG. 17A. FIG. 17IH is a view taken along arrows XXI-XXI of FIG. 17A. FIG. 17J is a view taken along arrows XXI-XXI of FIG. 17J. FIG. 23A is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23B is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23B is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIIIA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXIVA-XXIIIA in FIG. 22. FIG. 23C is a view taken along the arrows XXVC-XXVC in FIG. 25A. 26A is a cross-sectional view of a third airless tire according to a first example of the third embodiment, taken along the line XXVD-XXVD in FIG. 25A, and is a cross-sectional view of the third airless tire when the vehicle body is tilted.FIG. 26B is a cross-sectional view of a third airless tire according to a first example of the third embodiment, showing the third airless tire passing over an inclined road surface. FIG. 26C is a cross-sectional view of a third airless tire according to a first example of the third embodiment, showing the third airless tire passing over a fallen object on the road surface. FIG. 26D is a cross-sectional view of a third airless tire according to a first example of the third embodiment, showing the third airless tire running over a curb. FIG. 26E is a cross-sectional view of a third airless tire according to the first example of the third embodiment, showing the third airless tire passing over a step. FIG. 26F is a view taken along the arrows XXVIF-XXVIF in FIG. 26E. FIG. 26F is a view showing a casing, a compression coil spring, and a continuous crank leaf spring attached to a tire cover of a third airless tire according to a second example of the third embodiment. 29A is a diagram showing a procedure for attaching a compression coil spring and a continuous crank leaf spring to a casing, attaching the casing to a connecting portion, and attaching the connecting portion and a buffer portion to a tire cover in a third airless tire according to a second example of the third embodiment. 29B is a diagram showing the appearance of a pneumatic tire according to a third reference example. 29C is a view taken along the arrows XXIXB-XXIXB in FIG. 29A. 29D is a diagram showing the direction of force applied to a third airless tire according to a first example of the third embodiment.

[0013] 10, 110, 210... Wheel, 12, 112, 212... Rim, 20, 70, 120, 220... Tire cover, 25, 125, 225... Carcass, 30, 30A, 130, 130A, 230... Cushioning portion, 31, 31A, 131, 131A, 231... First cushioning portion, 32, 32A, 132, 132A, 232... Second cushioning portion, 40, 40A, 140, 140A, 140B, 240, 240A... Support portion, 43, 143, 143C, 243... Spacer, 43A, 243A... First spacer, 43B, 243B... Second spacer, 44, 144, 144A, 244... Connection portion, 1 00, 100A, 100B, 100C...first airless tire, 131c, 231c...first contact portion, 132b, 232b...second wing portion, 132c, 232c...second contact portion, 141, 141A, 141B...first straight portion, 142, 142A, 142B...second straight portion, 143A, 143B, 243a to 243g...divided spacer, 145, 145A, 145B...center portion, 200, 200A, 200B...second airless tire, 300, 300A...third airless tire, 400, 400A, 400B, 400C, 410, 410A, 410B, 420, 420A...assembly.

[0014] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0015] 1 to 3D , a first airless tire 100 according to a first example of the first embodiment will be described. Hereinafter, the direction perpendicular to the ground will be referred to as the up-down direction, the width direction of the first airless tire 100 will be referred to as the left-right direction, and the direction perpendicular to the up-down direction and the left-right direction will be referred to as the front-rear direction. The first airless tire 100 and first airless tires 100A, 100B, and 100C described below are relatively narrow tires and are used for relatively lightweight moving objects such as bicycles, assisted bicycles, and wheelchairs.

[0016] 1 , the first airless tire 100 includes a tire cover 20 and an assembly 400, and can be mounted on a wheel 10. The wheel 10 may be a wheel for a conventional pneumatic tire, for example, an ISO-standard wheel. Unlike conventional pneumatic tires, the first airless tires 100, 100A, 100B, and 100C do not have compressed air filled in the tire cover 20. The first airless tires 100, 100A, 100B, and 100C include the assembly 400 instead of compressed air.

[0017] In this embodiment, the wheel 10 is a conventional wheel for a pneumatic tire. For example, as shown in FIG. 1 , the wheel 10 includes a rim 12, a hub 11, and a plurality of spokes 13. The rim 12 is configured in an annular shape and has a first rim 12a and a second rim 12b. The hub 11 is a disk-shaped member and is disposed at the center of the annular shape of the rim 12. Each of the plurality of spokes 13 is a rod-shaped member and connects the hub 11 and the rim 12. In another embodiment, the wheel 10 may be a wheel other than a wheel for a pneumatic tire, as long as it has the same functions as the wheel 10 of this embodiment.

[0018] 2A to 2C, the assembly 400 is attached to the tire cover 20, and the tire cover 20 is assembled to the wheel 10. The tire cover 20 is a non-stretchable and flexible member, and includes an outer layer made of a thick rubber layer, resin, or the like, and an inner layer such as a carcass 25. The carcass 25 is a cord layer that forms the tire framework, and is made of fibers or metal fibers coated with rubber or the like.

[0019] The tire cover 20 also has a tread portion 21, two sidewall portions 22, two bead portions 23, a first end portion 23a, and a second end portion 23b.

[0020] The tread portion 21 is the portion that comes into direct contact with the road surface and has a tread pattern engraved thereon. The two sidewall portions 22 are disposed on both sides of the tread portion 21 and constitute the two side surfaces of the tire cover 20. The two sidewall portions 22 deflect when a load is applied to the first airless tire 100.

[0021] The bead portion 23 is formed by bundling wires into a ring shape and covering them with rubber or the like. One of the two bead portions 23, i.e., a first end portion 23a, is fitted and fixed to the first rim 12a, and the other, second end portion 23b, is fitted and fixed to the second rim 12b. The tire cover 20 can be used with conventional pneumatic tires and can also be filled with air.

[0022] The assembly 400 is disposed inside the tire cover 20 and over the entire circumferential circumference of the tire cover 20 so as to be in contact with the carcass 25. The assembly 400 is attached to the tire cover 20 in place of the air filling a conventional pneumatic tire, and has a load support function and a cushioning function similar to the air filling the tire.

[0023] As shown in Figures 2A-2C, the assembly 400 includes a buffer portion 30 and a support portion 40. The buffer portion 30 and the support portion 40 may be a single unitary member or separate units. The buffer portion 30 and the support portion 40 shown in Figures 2A-2C are a single unitary member.

[0024] The support portion 40 is a non-shrinkable and flexible member, and is made of, for example, hard rubber, thermoplastic resin (or special resin), carbon fiber, spring steel, steel, etc. The support portion 40 has an annular shape and is disposed so as to be in close contact with the inner surface of the tread portion 21. Here, "close contact" means that the surface of one member is in contact with the surface of another member without any gaps.

[0025] The support portion 40 is a band-shaped member rolled into an annular shape, and has a width along the width direction of the tire cover 20, i.e., a width along the width direction of the tread portion 21, and a thickness along the radial direction of the tire cover 20. The support portion 40 has a first edge portion 41 and a second edge portion 42. The first edge portion 41 is one of two ends along the circumferential direction of the band-shaped member, and the second edge portion 42 is the other of the two ends.

[0026] Specifically, the support portion 40 includes a band-shaped spacer 43 rolled into a ring shape and a band-shaped connecting portion 44 also rolled into a ring shape. The connecting portion 44 connects the first buffer portion 31 and the second buffer portion 32, which will be described later. The connecting portion 44, the first buffer portion 31, and the second buffer portion 32 may be configured from a single sheet-like member. The diameter of the spacer 43 and the connecting portion 44 are approximately the same. The spacer 43 is connected to the connecting portion 44 and, together with the connecting portion 44, forms a band-shaped member rolled into a ring shape. The support portion 40 is attached to the tire cover 20 so that the spacer 43 or the connecting portion 44 is in close contact with the inner surface of the tread portion 21.

[0027] The buffer section 30 is an elastic and flexible member, and is made of, for example, hard rubber, thermoplastic resin (or special resin), carbon fiber, spring steel, steel, or the like. The buffer section 30 includes a first buffer section 31 and a second buffer section 32. The first buffer section 31 extends around the entire circumference of the support section 40 from a first edge section 41 of the support section 40 toward the first end 23 a of the tire cover 20. The second buffer section 32 extends around the entire circumference of the support section 40 from a second edge section 42 toward the second end 23 b of the tire cover 20. The first buffer section 31 has a third end 31 a, and the second buffer section 32 has a fourth end 32 a.

[0028] 2A , the assembly 400 is inserted into the tire cover 20 with the first buffer portion 31 and the second buffer portion 32 in a deflected state, and attached to the tire cover 20. The first buffer portion 31 and the second buffer portion 32 are disposed so as to be in close contact with the inner surface of the sidewall portion 22. The support portion 40 is disposed so as to be in close contact with the inner surface of the tread portion 21.

[0029] 2B, the first end 23a and the second end 23b are attached to the first rim 12a and the second rim 12b with the assembly 400 attached to the tire cover 20. As a result, the tire cover 20 and the assembly 400 are assembled to the wheel 10 as shown in FIG.

[0030] When the tire cover 20 and the assembly 400 are mounted on the wheel 10, the third end 31a of the first buffer portion 31 is positioned radially outward of the wheel 10 and displaceable relative to the first end 23a of the tire cover 20. Furthermore, the fourth end 32a of the second buffer portion 32 is positioned radially outward of the wheel 10 and displaceable relative to the second end 23b of the tire cover 20. In other words, the assembly 400 is not physically connected to the wheel 10.

[0031] In the first airless tire 100, the assembly 400 and the wheel 10 are not in contact with each other, are not provided with connecting struts, and are not physically connected (i.e., are not physically connected). This prevents vibrations and noises from being transmitted from the assembly 400 to the wheel 10 during driving. This in turn reduces vibrations and noises transmitted from the first airless tire 100 to the vehicle body.

[0032] Because the first buffer portion 31 and the second buffer portion 32 have elasticity, they repel inward bending and tend to expand outward. As a result, the first buffer portion 31 and the second buffer portion 32 apply an outward force to the tire cover 20. In other words, the first buffer portion 31 and the second buffer portion 32 push the tire cover 20 outward in the width direction.

[0033] The first buffer portion 31 and the second buffer portion 32 push the tire cover 20 outward, thereby pressurizing the tire cover 20 against the rim 12. This prevents the tire cover 20 from coming off the rim 12.

[0034] The support portion 40 has a non-contractile annular shape, and its perimeter does not change even when an external force is applied. The tire cover 20 is non-stretchable and flexible. When the elasticity of the buffer portion 30 expands the sidewall portion 22 in the width direction, the tread portion 21 moves radially inward, shortening the perimeter of the tire cover 20. As a result, the non-stretchable tire cover 20 presses the non-contractable assembly 400, bringing the two layers of the tire cover 20 and the assembly 400 into close contact. Continuous pressure from the elasticity of the buffer portion 30 maintains the arch structure formed by the close contact of the two layers. Furthermore, the bead portion 23 of the tire cover 20 fits into the rim 12 of the wheel 10, which has a perfect circular shape, thereby maintaining the perfect circular shape of the tire cover 20 when no load is applied. In this embodiment, the annular shape of the tire cover 20 and the assembly 400 as viewed from the side of the first airless tire 100 is referred to as a longitudinal arch structure.

[0035] Furthermore, the first buffer portion 31 and the second buffer portion 32 push and spread the tire cover 20 outward, thereby maintaining the shape of the outwardly bulging sidewall portion 22 (specifically, the convex shape protruding to the left and right). In this embodiment, the fan shape of the tire cover 20 and the assembly 400 in a cross section along the radial direction is referred to as a lateral arch structure.

[0036] In the first airless tire 100, even if compressed air is not filled inside the tire cover 20, the support portion 40 maintains its longitudinal arch structure to support a load applied to the first airless tire 100. Furthermore, by maintaining their transverse arch structures, the first buffer portion 31 and the second buffer portion 32 absorb impacts applied to the first airless tire 100 and assist the deflected support portion 40 in restoring its shape.

[0037] The action of forces applied to the first airless tire 100 will be described with reference to FIGS. 3A to 3D. An "external force" corresponds to a load applied to the first airless tire 100 at the contact point. The loads applied to the first airless tire 100 include static loads and dynamic loads. A static load is a continuous load such as the weight of the vehicle body. A dynamic load is a load that occurs repeatedly during driving or a load that occurs temporarily such as an impact. The static load is supported by adjusting the strength of the assembly 400, which generates stress, to balance with the weight of the vehicle body, and supporting the load, thereby maintaining the assembly 400 in a substantially perfect circular shape. Of the loads, the dynamic load is supported by the elastic reaction force (restoring force) after deformation of the assembly 400.

[0038] "Stress" is an elastic force generated in the arch-structured assembly 400 when subjected to an external force, which is a load. The support portion 40 of the assembly 400 deforms due to its non-contractibility and flexibility to support the dynamic load, and the buffer portion 30 of the assembly 400 absorbs shock due to its elasticity and flexibility and assists in the restoration of the support portion 40 that has been deformed due to the application of the dynamic load.

[0039] The reaction force is a movable reaction force generated in the tire cover 20, which is an inextensible, flexible ring that covers the assembly 400 where stress occurs. The reaction force restricts deformation of the assembly 400 due to dynamic load load within the movable range of the tire cover 20, and supports the restoring force due to the elasticity of the assembly 400, converting it into a reaction force. In other words, the tire cover 20, like a conventional tire cover, has both a load support function and a shock-absorbing function.

[0040] The first airless tire 100 efficiently functions due to the continuous close contact between the two layers, the non-stretchable tire cover 20 and the non-shrinkable assembly 400. The close contact between the two layers, the tire cover 20 and the assembly 400, is achieved by the elasticity of the buffer section 30 of the assembly 400. Specifically, in the first airless tire 100, the non-shrinkable support section 40 is disposed in close contact with the inner surface of the non-stretchable tread section 21, thereby distributing the load (i.e., external force) received at the ground contact surface around the entire circumference of the support section 40, reducing the surface pressure and improving the load support efficiency. This allows the assembly 400 to be made more compact and lighter. In addition, the elasticity of the buffer section 30 pushes the sidewall section 22 outward in the width direction, forming a convex shape, creating a range of motion for the support section 40 to flex, which is necessary for the buffer function. Furthermore, the elasticity of the buffer portion 30 pressurizes the flexible sidewall portion 22, maintaining the two layers of the tire cover 20 and the assembly 400 in a tight contact state, thereby enabling the compatibility of the load-bearing function and the buffering function, which are contradictory functions of rigidity and flexibility.

[0041] 3A and 3D , a load (i.e., an upward external force) is applied to the first airless tire 100 at the ground contact point of the first airless tire 100. When a dynamic load is applied to the first airless tire 100, the flexible support portion 40 bends upward at the ground contact point, creating a gap between the support portion 40 and the carcass 25. Furthermore, when a dynamic load is applied to the first airless tire 100, the elasticity of the first buffer portion 31 and the second buffer portion 32 pushes the inextensible carcass 25 apart in the left-right direction. Because the bead portion 23 is restrained by the rim 12, when the carcass 25 is pushed apart in the left-right direction, the reaction force generated in the rim 12 and the movable reaction force generated in the carcass 25 bring the two layers of the tire cover 20 and the assembly 400 into close contact, and the lateral arches and the longitudinal arches of the support portion 40 absorb the dynamic load. At this time, the assembly 400 supports the load without coming into contact with the wheel 10, so that transmission of vibrations and noise generated at the contact surface to the vehicle body is suppressed.

[0042] As shown in Figures 3A and 3B, the movable reaction force of the carcass 25 tightly holds the assembly 400 against the inside of the carcass 25, and when the load at the contact point is only a static load, the tire cover 20 and the assembly 400 maintain a nearly perfect circular shape. When an upward dynamic load is applied to the contact point, the flexible support portion 40 bends and bulges forward, pushing the inextensible and flexible carcass 25 forward and narrowing inward in the left-right direction. At the same time, the first buffer portion 31 and the second buffer portion 32, which are horizontal arches restrained by the reaction force of the carcass 25, are also squeezed like a bow and pushed inward, gradually increasing the elastic recoil force. When the load of the external force that is deflected forward through the support portion 40, which is a vertical arch, and released is balanced with the elastic recoil force of the buffer portion 30, the dynamic load is supported. When the dynamic load at the contact point is removed, the force pushing the support portion 40, which is a longitudinal arch, forward decreases, and the recoil force due to the elasticity of the first buffer portion 31 and the second buffer portion 32, which are transverse arches, becomes greater, pushing the carcass 25 outward in the left-right direction and pushing back the elliptically bent support portion 40, restoring it to a substantially perfect circle. As described above, in the first airless tire 100, the elasticity of the first buffer portion 31 and the second buffer portion 32 controls the amount of bending of the support portion 40, thereby achieving both the conflicting functions of load support function and buffer function.

[0043] As shown in FIGS. 3A and 3C, the rear side of the first airless tire 100 undergoes operations symmetrical to those of the front side of the first airless tire 100 shown in FIG. 3B.

[0044] 3D , when the dynamic load applied to the first airless tire 100 is removed at the ground contact point of the first airless tire 100, the elastic forces of the first buffer section 31 and the second buffer section 32 restore the shape of the support section 40 via the carcass 25. As shown in FIGS. 3B and 3C , the elliptical deflection of the support section 40 is pushed back toward the wheel 10, and the upward deflection of the support section 40 due to buffering at the ground contact point is pushed back downward, restoring the shape of the support section 40 to a substantially perfect circle, thereby supporting the static load.

[0045] As the assembly 400 is displaced, the annular shape of the tire cover 20 deforms, shrinking in the up-down direction and expanding in the front-to-rear direction. That is, the shape of the tire cover 20 deforms from a perfect circle to an ellipse. Furthermore, the tire cover 20 deforms so as to expand in the left-to-right direction at the contact point and to narrow in the left-to-right direction at the front and rear sides. Then, due to the elastic forces of the first buffer section 31 and the second buffer section 32 and the reaction force of the carcass 25, the assembly 400 returns to its original position (i.e., the position when no dynamic load is applied to the first airless tire 100). That is, the tire cover 20 deforms when a dynamic load is applied, and returns to a substantially perfect circle when the dynamic load is removed.

[0046] That is, the support portion 40 receives the reaction force of the carcass 25, maintains the longitudinal arch structure, and supports the load applied to the first airless tire 100. The first buffer portion 31 and the second buffer portion 32 maintain the two-layer close contact structure between the assembly 400 and the tire cover 20, and therefore the lateral arch structure, and absorb impacts applied to the first airless tire 100 while assisting the support portion 40 in restoring its shape when bent.

[0047] 14A to 14C show a bicycle pneumatic tire 150 according to a reference example. The pneumatic tire 150 includes a circular rubber tube 28 instead of the assembly 400. The tube 28 is positioned inside the tire cover 20, contacting the carcass 25, and extends around the entire circumferential direction of the tire cover 20. The tube 28 is filled with compressed air. When a temporary dynamic load is applied to the pneumatic tire 150 at its contact point with the ground, the surface pressure at the contact patch increases, and the air at the inflated pressure is forced out (flows) to other areas. This increases the contact area, reducing the surface pressure. The inflated pressure and the contact pressure at the contact patch (ground pressure) balance, and the cushioning effect of the pneumatic tire 150 ceases. When the temporary dynamic load is removed and the only load applied to the pneumatic tire 150 is a static load, the surface pressure at the contact patch decreases further, and the air at the inflated pressure is forced back out (flows) to the recessed area due to cushioning, thereby supporting the static load. Then, as the contact area narrows back to its original state, the surface pressure under static load and the filling pressure balance, and the shape of the pneumatic tire 150 is restored. The carcass 25 of the tire cover 20 attached to the vehicle has enough strength (i.e., reaction force) to prevent expansion or rupture even when filled with air at a load-bearing pressure equal to or greater than the maximum load (safety factor) that the vehicle can bear. Because the pneumatic tire 150 is filled with air adjusted to an appropriate pressure that provides a good balance between load support and cushioning, the pneumatic tire 150 maintains a substantially perfect circular shape and supports static load. That is, in the pneumatic tire 150, the filled air has a load-supporting function and a cushioning function.

[0048] 1-2. Second Example of First Airless Tire A first airless tire 100A according to a second example of the first embodiment will be described with reference to Figures 4A to 7. The basic configuration is similar to that of the first example of the first embodiment, and differences will be described below. Note that the same reference numerals as those in the first example of the first embodiment indicate the same configuration, and the preceding description will be referred to.

[0049] A first airless tire 100A according to a second example of the first embodiment includes an assembly 400A instead of the assembly 400. The assembly 400A includes a support portion 40 and a buffer portion 30A. That is, the assembly 400A differs from the assembly 400 in that the assembly 400A includes a buffer portion 30A instead of the buffer portion 30. The buffer portion 30A includes a first buffer portion 31A and a second buffer portion 32A. As shown in FIG. 6 , the first buffer portion 31A and the second buffer portion 32A have cutout portions 33 formed at regular intervals in the circumferential direction. The formation of the cutout portions 33 allows the first buffer portion 31A and the second buffer portion 32A to easily conform to the convex shape of the sidewall portion 22. Consequently, the elastic force of the first buffer portion 31A and the second buffer portion 32A easily applies pressure to the inner surface of the sidewall portion 22. This makes it easier to restore the shape of the tire cover 20 to a perfect circle when an external force is applied to the first airless tire 100A and the tire cover 20 is bent.

[0050] The first buffer section 31A and the second buffer section 32A may each include a plurality of stacked sheet members. In this case, each of the plurality of sheet members included in the first buffer section 31A has a third end 31a, and the plurality of sheet members included in the first buffer section 31A have different lengths from the first edge section 41 to the third end 31a. Furthermore, each of the plurality of sheet members included in the second buffer section 32A has a fourth end 32a, and the plurality of sheet members included in the second buffer section 32A have different lengths from the second edge section 42 to the fourth end 32a.

[0051] In this way, since the first buffer portion 31A and the second buffer portion 32A are made up of multiple sheet members, the first buffer portion 31A and the second buffer portion 32A are more likely to conform to the convex shape of the sidewall portion 22 than if they were made up of a single sheet member.

[0052] 1-3. Third Example of First Airless Tire A first airless tire 100B according to a third example of the first embodiment will be described with reference to Figures 8 to 10C. The basic configuration is similar to that of the first example of the first embodiment, and differences will be described below. Note that the same reference numerals as those in the first example of the first embodiment indicate the same configuration, and the preceding description will be referred to.

[0053] A first airless tire 100B according to a third example of the first embodiment includes an assembly 400B instead of the assembly 400. The assembly 400B includes a support portion 40A and a buffer portion 30. That is, the assembly 400B differs from the assembly 400 in that it includes a support portion 40A instead of the support portion 40.

[0054] The support portion 40A includes a first spacer 43A or a second spacer 43B and a connecting portion 44. The support portion 40A differs from the support portion 40 in that the support portion 40A includes a first spacer 43A or a second spacer 43B instead of the spacer 43. As shown in FIG. 8 , the first spacer 43A is a compression coil spring member and has an annular shape (connected) without ends. The second spacer 43B is a continuous crank leaf spring and has an annular shape (connected) without ends. In an unloaded state before attachment to the tire cover 20, the circumferential lengths of the first spacer 43A and the second spacer 43B are both longer than the circumferential length of the tire cover 20. Each of the first spacer 43A and the second spacer 43B is compressed and attached to the tire cover 20.

[0055] The first spacer 43A is formed by spirally winding a rod-shaped metal member or the like, and the second spacer 43B is formed by repeatedly crank-bending (or Z-bending) a plate-shaped metal member or the like. As shown in Figures 9B and 10B, the first spacer 43A has a circular cross section, and the second spacer 43B has a square cross section.

[0056] 9A and 9C, the first spacer 43A is mounted in a compressed state to the tire cover 20. Similarly, as shown in Figures 10A and 10C, the second spacer 43B is mounted in a compressed state to the tire cover 20 so that the width direction of the plate is the left-right direction.

[0057] The first spacer 43A and the second spacer 43B apply pressure to the tire cover 20 by their extension force. The load applied to the first airless tire 100B is supported by the extension force of the first spacer 43A and the second spacer 43B and the reaction force of the carcass 25. Furthermore, the first spacer 43A and the second spacer 43B deform to absorb impacts applied to the first airless tire 100B. That is, the first spacer 43A and the second spacer 43B have a buffering function that absorbs impacts applied to the first airless tire 100B according to the degree of freedom of their shape (i.e., the degree of deformability).

[0058] 1-4. Fourth Example of First Airless Tire A first airless tire 100C according to a fourth example of the first embodiment will be described with reference to Figures 11 to 13C. The basic configuration is similar to that of the first example of the first embodiment, and differences will be described below. Note that the same reference numerals as those in the first example of the first embodiment indicate the same configuration, and the preceding description will be referred to.

[0059] A first airless tire 100C according to a fourth example of the first embodiment includes an assembly 400C instead of the assembly 400. The assembly 400C includes a first compression coil spring 43C or a second compression coil spring 43D. The assembly 400C differs from the assembly 400 in that the buffer section 30 and the support section 40 are integrated, and both the first compression coil spring 43C and the second compression coil spring 43D serve as both the buffer section 30 and the support section 40. The first compression coil spring 43C has a circular ring shape (connected) without ends. The second compression coil spring 43D has a circular ring shape (connected) without ends. The circumferential lengths of both springs are longer than the circumferential length of the tire cover 20. Each of the first compression coil spring 43C and the second compression coil spring 43D is compressed and attached to the tire cover 20.

[0060] As shown in Fig. 12B, the first compression coil spring 43C is formed by bending a plate-shaped member such as resin so as to have a semicircular cross section, and as shown in Fig. 13B, the second compression coil spring 43D is formed by bending a plate-shaped member such as resin so as to have an oval cross section.

[0061] 12A and 12B, the first compression coil spring 43C is mounted to the tire cover 20 in a compressed state with the diameter of its semicircular cross section oriented in the left-right direction (i.e., the width direction of the tire cover 20). Also, as shown in Figures 13A and 13B, the second compression coil spring 43D is mounted to the tire cover 20 in a compressed state with the major axis of its elliptical cross section oriented in the left-right direction.

[0062] The first compression coil spring 43C and the second compression coil spring 43D apply pressure to the tire cover 20 by their extension forces. The load applied to the first airless tire 100C is supported by the extension forces of the first compression coil spring 43C and the second compression coil spring 43D and the reaction force of the carcass 25. Furthermore, the first compression coil spring 43C and the second compression coil spring 43D absorb impacts applied to the first airless tire 100C and restore the first airless tire 100C to its original shape after deformation due to the load.

[0063] <1-5. Effects> According to the first embodiment described above in detail, the following effects are achieved.

[0064] (1) In the assemblies 400, 400A, 400B, and 400C, the support portions 40, 40A, 43C, and 43D are disposed in close contact with the inner surface of the tread portion 21 of the tire cover 20, thereby maintaining the longitudinal arch structure of the first airless tire 100, 100A, 100B, and 100C. Consequently, there are no struts connecting the support portions 40, 40A, 43C, and 43D to the wheel 10, and even if compressed air is not filled inside the tire cover 20, the support portions 40, 40A, 43C, and 43D can efficiently support static and dynamic loads applied to the first airless tire 100, 100A, 100B, and 100C. Furthermore, the absence of struts can reduce vibrations and noise transmitted to the vehicle body via the first airless tire 100, 100A, 100B, and 100C. Therefore, the first airless tires 100, 100A, 100B, 100C can have load-bearing performance, vibration-damping performance, and quietness performance.

[0065] (2) In assemblies 400, 400A, 400B, 400C, the first buffer portions 31, 31A, 43C, 43D and the second buffer portions 32, 32A, 43C, 43D, which have elasticity and flexibility, push the sidewall portion 22 of the tire cover 20 in the width direction of the tire cover 20, thereby pressing the first end portion 23a and the second end portion 23b against the rim 12, thereby preventing the tire cover 20 from detaching from the rim 12. Furthermore, when a load is applied to the first airless tire 100, 100A, 100B, 100C and the support portions 40, 40A, 43C, 43D are deflected, the elastic forces of the first buffer portions 31, 31A, 43C, 43D and the second buffer portions 32, 32A, 43C, 43D assist the support portions 40, 40A, 43C, 43D in restoring their original shape, and the first airless tire 100, 100A, 100B, 100C is thereby provided with cushioning performance.

[0066] (3) In the first airless tire 100, 100A, 100B, the support portion 40, 40A includes the connecting portion 44 that connects the first buffer portion 31, 31A and the second buffer portion 32, 32A. This prevents the first buffer portion 31, 31A and the second buffer portion 32, 32A from moving away from each other in the width direction when the support portion 40, 40A is subjected to a load. Consequently, when the support portion 40, 40A is subjected to a load, the first buffer portion 31, 31A and the second buffer portion 32, 32A are pressurized, and the elastic force of the first buffer portion 31, 31A and the second buffer portion 32, 32A maintains the shape of the first airless tire 100, 100A, 100B.

[0067] (4) In the first airless tire 100, 100A, the support portion 40 and the buffer portion 30, 30A are integral members. Therefore, the first buffer portion 31, 31A and the second buffer portion 32, 32A can be displaced in response to the deflection of the support portion 40, and the elastic force of the first buffer portion 31, 31A and the second buffer portion 32, 32A can easily assist in the restoration of the support portion 40.

[0068] (5) In the first airless tire 100A, the first buffer portion 31A and the second buffer portion 32A have the cutout portions 33 formed at regular intervals. This allows the first buffer portion 31A and the second buffer portion 32A to easily conform to the convex shape of the sidewall portion 22 of the tire cover 20. Consequently, the elastic force of the first buffer portion 31A and the second buffer portion 32A easily applies pressure to the inner surface of the sidewall portion 22. As a result, when the first airless tire 100A is deflected by the application of a load, the shape of the first airless tire 100A can be restored and maintained in a substantially perfect circular shape.

[0069] (6) In the first airless tire 100, 100A, when the first buffer portion 31, 31A and the second buffer portion 32, 32A include a plurality of sheet members having different lengths, the first buffer portion 31, 31A and the second buffer portion 32, 32A can suitably expand the tire cover 20 in the width direction. This allows the sidewall portion 22 of the tire cover 20 to suitably maintain a convex shape that protrudes in the width direction. This in turn allows the lateral arch structure of the first airless tire 100, 100A to be suitably maintained.

[0070] (7) In the first airless tires 100B, 100C, the inextensible tire cover 20 serves as a casing for the first and second spacers 43A, 43B and the first and second compression coil springs 43C, 43D. By attaching an annular compression spring member having a circumferential length longer than that of the tire cover 20 to the tire cover 20, the extension force of the compression spring member constantly pressurizes the tire cover 20. Therefore, the compression spring member can support a load applied to the first airless tire 100B, 100C. Furthermore, when the first airless tire 100B, 100C receives an impact, the compression spring member can freely deform to absorb the impact.

[0071] Second Embodiment 2-1. First Example of Second Airless Tire A second airless tire 200 according to a first example of the second embodiment will be described with reference to Figures 15 to 17D. The same reference numerals as those in the first embodiment indicate the same components, and reference is made to the preceding description.

[0072] The second airless tire 200 and second airless tires 200A and 200B described below are tires of a medium width and are wider than the first airless tires 100, 100A, 100B, and 100C. The second airless tires 200, 200A, and 200B are applied to medium-weight mobile objects such as two-wheeled vehicles (i.e., motorcycles) and three-wheeled vehicles equipped with a power source such as an engine or a motor.

[0073] 15 , the second airless tire 200 includes a tire cover 120 that can be attached to a wheel 110, and an assembly 410. The wheel 110 may be a conventional wheel for a pneumatic tire, for example, an ISO standard wheel. In this embodiment, a conventional wheel for a pneumatic tire is used as the wheel 110. The second airless tires 200, 200A, 200B include the assembly 410 instead of the tire cover 120 being filled with compressed air.

[0074] The wheel 110 includes a rim 112, a hub 111, and a plurality of spokes 113. The wheel 110 has a similar configuration to the wheel 10, and details thereof will be omitted. The tire cover 120 is an inextensible member made of rubber, resin, or the like, and includes a tread portion 121, sidewall portions 122 extending on both sides, two bead portions 123, a carcass 125, a first end portion 123a, and a second end portion 123b. The tire cover 120 has a similar configuration to the tire cover 20, and details thereof will be omitted. The tire cover 120 can be a tire cover for a conventional pneumatic tire, and can also be filled with air.

[0075] 16 , the assembly 410 includes a buffer section 130 and a support section 140. The support section 140 is a separate member from the buffer section 130. The support section 140 includes a ring-shaped spacer 143 and a band-shaped connecting section 144 that is rolled into a ring shape.

[0076] The connecting portion 144 is formed of a non-extensible and flexible material, and connects the first buffer portion 131 and the second buffer portion 132, which will be described later. The connecting portion 144 is disposed so as to be in close contact with the inner surface of the tread portion 121.

[0077] The spacer 143 is a non-shrinkable, flexible, annular member made of, for example, hard rubber, thermoplastic resin (or special resin), carbon fiber, spring steel, steel, etc. The spacer 143 has a width in the left-right direction and is disposed so as to be in close contact with the inner surface of the connecting portion 144. The spacer 143 is formed in an arch shape including a central portion 145 that is in close contact with the connecting portion 144, and a first linear portion 141 and a second linear portion 142 that extend from each end of the central portion 145 toward the wheel 110. In other words, the spacer 143 has a U-shaped radial cross section.

[0078] The first buffer portion 131 includes a first blade portion 131b and a first contact portion 131c. The first blade portion 131b has a third end portion 131a and is disposed so as to contact the inner surface of the sidewall portion 122. The first contact portion 131c is bent relative to the first blade portion 131b and is disposed so as to contact the first linear portion 141 of the spacer 143.

[0079] The second buffer portion 132 includes a second blade portion 132b and a second contact portion 132c. The second blade portion 132b has a fourth end portion 132a and is disposed so as to contact the inner surface of the sidewall portion 122. The second contact portion 132c is bent relative to the second blade portion 132b and is disposed so as to contact the second linear portion 142 of the spacer 143.

[0080] As shown in FIG. 16 , first, the first buffer portion 131 , the second buffer portion 132 and the connecting portion 144 of the assembly 410 are inserted into the tire cover 120 and attached to the tire cover 120 .

[0081] Next, spacer 143 is inserted between first buffer portion 131 and second buffer portion 132. At this time, first buffer portion 131 and second buffer portion 132 are connected by connecting portion 144, so that first buffer portion 131 and second buffer portion 132 do not move in the left-right direction away from each other. As a result, first linear portion 141 and second linear portion 142 come into contact with first contact portion 131c and second contact portion 132c, and apply pressure to first blade portion 131b and second blade portion 132b via first contact portion 131c and second contact portion 132c.

[0082] Then, with the assembly 410 attached to the tire cover 120, the first end 123a and the second end 123b are attached to the first rim 112a and the second rim 112b. The tire cover 120 is pressurized outward and pressed against the rim 112. This prevents the tire cover 120 from coming off the rim 112.

[0083] The carcass 125 suppresses outward stress in the connecting portion 144, the central portion 145, the first wing portion 131b, and the second wing portion 132b. As a result, the connecting portion 144, the first wing portion 131b, and the second wing portion 132b are in direct and intimate contact with the inner surface of the tire cover 120, forming a two-layer intimate contact structure. The central portion 145 is in intimate contact with the inner surface of the connecting portion 144. As a result, the annular shape of the tire cover 120 is maintained. Furthermore, the first wing portion 131b and the second wing portion 132b push the tire cover 120 outward in the left-right direction, thereby maintaining the shape of the sidewall portion 122 that bulges in the left-right direction.

[0084] When the tire cover 120 and the assembly 410 are mounted on the wheel 110, the third end 131a of the first wing portion 131b is located radially outward of the wheel 110 relative to the first end 123a of the tire cover 120 and is displaceable. Furthermore, the fourth end 132a of the second wing portion 132b is located radially outward of the wheel 110 relative to the second end 123b of the tire cover 120 and is displaceable. In other words, the second airless tire 200 does not include a support that physically connects the assembly 410 to the wheel 110, and the assembly 410 is not physically connected to the wheel 110 and does not come into contact with it. This reduces vibration and noise transmitted from the second airless tire 200 to the vehicle body.

[0085] In the second airless tire 200, the spacer 143 maintains the longitudinal arch structure, thereby supporting the load applied to the second airless tire 200. Furthermore, the first buffer portion 131 and the second buffer portion 132 maintain the transverse arch structure, thereby absorbing the impact applied to the second airless tire 200 and assisting the deflected support portion 140 in restoring its shape.

[0086] 17A to 17D, the action of forces applied to the second airless tire 200 will be described. As shown in FIGS. 17A and 17D, when an upward load (external force) is applied to the second airless tire 200 at the ground contact point during running, the annular spacer 143 bends upward (inward) to absorb the external force, and the load (external force) is released outward in the areas other than the ground contact point. At the same time, the elasticity of the buffer section 130, which is suppressed by the carcass 125, applies inward stress to the spacer 143 in the areas other than the ground contact point, causing the shape of the assembly 410 to be restored. As a result, the load applied to the second airless tire 200 is supported.

[0087] 17A and 17B , when an upward external force is applied to the second airless tire 200 at the contact patch, the spacer 143 bends and bulges forward at the front to release the load, and at the same time, the first wing portion 131b and the second wing portion 132b, which are restrained by the reaction force of the extruded carcass 125, are brought closer to each other in the left-right direction. When the load (external force) is removed, the elastic reaction force of the buffer portion 130 causes the wing portions to move apart in the left-right direction and return to their original shape, and at the same time, the bent spacer 143 is pushed back rearward, restoring the shape of the second airless tire 200. Within the movable range permitted by the non-extensible carcass 125, the buffer portion 130 is restrained from moving in the left-right direction, and the spacer 143 is restrained from moving up-down and fore-aft. This allows shock absorption and load support to occur in tandem.

[0088] As shown in FIGS. 17A and 17C, the rear side of the second airless tire 200 undergoes operations symmetrical to those of the front side of the second airless tire 200 shown in FIG. 17B.

[0089] That is, the spacer 143 receives the reaction force of the carcass 125, maintains the longitudinal arch structure, and supports the load applied to the second airless tire 200. The first wing portion 131b and the second wing portion 132b maintain the two-layer close contact structure between the assembly 410 and the tire cover 120, and therefore the lateral arch structure, and absorbs impacts applied to the second airless tire 200 and assists in restoring the shape of the bent support portion 140.

[0090] 20 and 21 show a motorcycle pneumatic tire 250 according to a reference example. Instead of an assembly 410, the pneumatic tire 250 is filled with compressed air within a tire cover 120. When a temporary dynamic load is applied to the pneumatic tire 250 at its contact point with the ground, the surface pressure at the contact patch increases, and the air at the inflated pressure is pushed out (flows) to other areas. This increases the contact area, reducing the surface pressure. The inflated pressure and the contact pressure at the contact patch (ground pressure) balance, and the cushioning effect of the pneumatic tire 250 ceases. When the temporary dynamic load is removed and the only load applied to the pneumatic tire 250 is a static load, the surface pressure at the contact patch further decreases, and the air at the inflated pressure is pushed back (flows) to the recessed area caused by cushioning, supporting the static load. The contact patch then narrows, restoring its original shape, balancing the surface pressure under static load and the inflated pressure, and the pneumatic tire 250 returns to its original shape. The carcass 125 of the tire cover 120 attached to the vehicle has sufficient strength (i.e., reaction force) to withstand inflation or rupture even when filled with air at a load-bearing pressure (safety factor) equal to or greater than the maximum load the vehicle can bear. Because the air is filled at an appropriate pressure that provides a good balance between load support and cushioning, the pneumatic tire 250 maintains a substantially perfect circular shape and supports static loads. In other words, the air filled in the pneumatic tire 250 has both a load-supporting function and a cushioning function.

[0091] 2-2. Second Example of Second Airless Tire A second airless tire 200A according to a second example of the second embodiment will be described with reference to Figure 18. The basic configuration is similar to that of the first example of the second embodiment, and differences will be described below. Note that the same reference numerals as those in the first example of the second embodiment indicate the same configuration, and the preceding description will be referred to.

[0092] A second airless tire 200A according to a second example of the second embodiment includes an assembly 410A instead of the assembly 410. The assembly 410A includes a support portion 140A and a buffer portion 130. The buffer portion 130 includes a first buffer portion 131 and a second buffer portion 132. The support portion 140A includes divided spacers 143A and 143B, and a connecting portion 144. In other words, the support portion 140A includes divided spacers 143A and 143B instead of the spacer 143.

[0093] The divided spacer 143A is formed in an arch shape including a first linear portion 141A, a second linear portion 142A, and a central portion 145A. The central portion 145A has a width in the left-right direction and is in close contact with the connecting portion 144. The first linear portion 141A and the second linear portion 142A extend from both ends of the central portion 145A toward the wheel 110. Similarly, the divided spacer 143B is formed in an arch shape including a first linear portion 141B, a second linear portion 142B, and a central portion 145B. The divided spacers 143A, 143B are similar to the spacer 143 of the support portion 140 of the second airless tire 200.

[0094] The width in the left-right direction of each of the central portions 145A, 145B is half or approximately half the width in the left-right direction of the central portion 145 of the spacer 143. In other words, the support portion 140A includes, instead of one spacer 143, two divided spacers 143A, 143B.

[0095] 18 , the split spacers 143A and 143B are attached to the inside of the tire cover 120 in place of the spacer 143. That is, the split spacers 143A and 143B are inserted between the first buffer portion 131 and the second buffer portion 132. The split spacers 143A and 143B are arranged so that the central portions 145A and 145B are in close contact with the connecting portion 144, the first linear portion 141A is in contact with the first contact portion 131c, the second linear portion 142A is in contact with the first linear portion 141B, and the second linear portion 142B is in contact with the second contact portion 132c.

[0096] Because the spacer is divided into multiple pieces, when a vehicle equipped with the second airless tire 200A travels on an uneven road surface, the divided spacers 143A and 143B are displaced individually, making it easier for the tread portion 121 to adapt to the shape of the road surface. This in turn increases the contact area of ​​the second airless tire 200A, allowing the second airless tire 200A to stably support the load and improving the grip of the second airless tire 200A. Note that the support portion 140A may be provided with a divided spacer divided into three or more pieces instead of a single spacer 143.

[0097] In the second airless tire 200A, the divided spacers 143A, 143B have the same function as the spacer 143. That is, the divided spacers 143A, 143B support a load applied to the second airless tire 200A by maintaining the longitudinal arch structure. Furthermore, the first buffer portion 131 and the second buffer portion 132 maintain the transverse arch structure, thereby absorbing impacts applied to the second airless tire 200A and assisting the deflected support portion 140A in restoring its shape.

[0098] 2-3. Third Example of Second Airless Tire A second airless tire 200B according to a third example of the second embodiment will be described with reference to Figure 19. The basic configuration is similar to that of the first example of the second embodiment, and differences will be described below. Note that the same reference numerals as those in the first example of the second embodiment indicate the same configuration, and the preceding description will be referred to.

[0099] A second airless tire 200B according to a third example of the second embodiment includes an assembly 410B instead of the assembly 410. The assembly 410B includes a support portion 140B and a buffer portion 130A. The buffer portion 130A includes a first buffer portion 131A and a second buffer portion 132A. The support portion 140B includes a spacer 143C and a connecting portion 144A. The configuration of the assembly 410B is similar to that of the assembly 400 of the first airless tire 100.

[0100] In the second airless tire 200B, the spacer 143C supports a load applied to the second airless tire 200B by maintaining the longitudinal arch structure. Furthermore, the first buffer portion 131A and the second buffer portion 132A maintain the transverse arch structure, thereby absorbing impacts applied to the second airless tire 200B and assisting the deflected support portion 140B in restoring its shape.

[0101] 2-4. Effects The second embodiment described above in detail provides the same effects as the effects (1) to (3) of the first embodiment described above. Furthermore, the second airless tire 200B further provides the same effects as the effects (4) to (7) of the first embodiment described above. Furthermore, the second embodiment provides the following effects.

[0102] (8) In the second airless tire 200, the support portion 140 is formed in an arch shape. Therefore, when the central portion 145 is deflected by a load, the first straight portion 141 and the second straight portion 142 are restored to their original shape by receiving the elastic force of the buffer portion 130. Therefore, by forming the support portion 140 in an arch shape, the load-bearing performance and buffer performance of the second airless tire 200 can be improved.

[0103] (9) In the second airless tire 200A, by configuring the support portion 140A with multiple divided spacers 143A, 143B, it is possible to divide and support the load applied to the second airless tire 200A. Furthermore, when the wide second airless tire 200A travels on an uneven or sloped road surface, the divided spacers 143A, 143B individually displace to adapt to the shape of the road surface. As a result, the contact area of ​​the second airless tire 200A is increased, allowing the second airless tire 200A to stably support the load and increasing the grip of the second airless tire 200A.

[0104] (10) In the second airless tire 200A, each of the divided spacers 143A, 143B is formed in an arch shape. Therefore, when one of the divided spacers is deflected under load, the straight portion of that divided member receives the elastic force of the straight portion of the other divided spacer and returns to its original shape. Therefore, by forming each divided spacer in an arch shape, the load-bearing capacity and cushioning performance of the second airless tire 200A can be improved.

[0105] (11) In the second airless tire 200, 200A, the support portion 140, 140A and the buffer portion 130 are separate members, and the first contact portion 131c and the second contact portion 132c of the buffer portion 130 contact both sides of the support portion 140, 140A, thereby preventing the support portion 140, 140A from moving in the width direction. Furthermore, the elastic force of the first wing portion 131b and the second wing portion 132b of the buffer portion 130 allows the second airless tire 200, 200A to restore its shape.

[0106] Third Embodiment 3-1. First Example of Third Airless Tire A third airless tire 300 according to a first example of the third embodiment will be described with reference to Figures 22 to 26F. The basic configuration is similar to that of the second embodiment, so differences will be described below. The third airless tire 300 and a third airless tire 300A, which will be described later, are relatively wide tires, wider than the second airless tires 200, 200A, and 200B. The third airless tires 300 and 300A are used for relatively heavy mobile objects such as four-wheeled vehicles (i.e., automobiles) equipped with a power source such as an engine or a motor.

[0107] 22 , the third airless tire 300 includes a tire cover 220 that can be attached to a wheel 210, and an assembly 420. The wheel 210 may be a conventional wheel for a pneumatic tire, for example, an ISO standard wheel. In this embodiment, a conventional wheel for a pneumatic tire is used as the wheel 210. The third airless tire 300, 300A includes an assembly 410 instead of the tire cover 220 being filled with compressed air.

[0108] The wheel 210 includes a rim 212, a hub 211, and a plurality of spokes 213. The wheel 210 has a similar configuration to the wheel 10, and details thereof will be omitted. As shown in Figures 23A to 23C, the tire cover 220 is an inextensible member and includes a tread portion 221, sidewall portions 222 extending on both sides, two bead portions 223, a carcass 225, two bead fillers 224, a first end portion 223a, and a second end portion 223b. The bead fillers 224 are reinforcing materials for the bead portions 223 and increase the rigidity of the bead portions 223. A conventional pneumatic tire cover can be used for the tire cover 220, and it is also possible to fill it with air.

[0109] 23A to 23C, assembly 420 includes buffer section 230 and support section 240. Support section 240 is a separate member from buffer section 230. Support section 240 includes an annular spacer 243 and a band-like connecting section 244 that is rolled into an annular shape.

[0110] The connecting portion 244 is formed of a non-extensible and flexible material, and connects the first buffer portion 231 and the second buffer portion 232, which will be described later. The connecting portion 244 is similar to the connecting portion 144 of the support portion 140 of the second airless tire 200. The connecting portion 244 is disposed so as to be in close contact with the inner surface of the tread portion 221.

[0111] The spacer 243 includes seven divided spacers 243a to 243g. The spacer 243 may not be divided, i.e., may be a single spacer. The spacer 243 may also include two to six divided spacers, or seven or more divided spacers.

[0112] Each of the divided spacers 243a to 243g is formed in an arch shape that includes a central portion and a first linear portion and a second linear portion that extend from each of both ends of the central portion toward the wheel 210. In other words, each of the divided spacers 243a to 243g has a U-shaped radial cross section and is similar to the spacer 143 of the support portion 140 of the second airless tire 200.

[0113] The divided spacers 243a to 243g are arranged side by side in the left-right direction inside the tire cover 220. The divided spacers 243a to 243g are arranged so that the center portion of each of the divided spacers 243a to 243g is in close contact with the inner surface of the connecting portion 244 and so that the first linear portion of each of the divided spacers 243b to 243g is in contact with the second linear portion of the adjacent divided spacer on the front side. The first linear portion of the divided spacer 243a is in contact with the first buffer portion 231, and the second linear portion of the divided spacer 243g is in contact with the second buffer portion 232.

[0114] The first buffer portion 231 includes a first blade portion 231b and a first contact portion 231c bent relative to the first blade portion 231b. The first blade portion 231b has a third end portion 231a. The first buffer portion 231 is disposed such that the first blade portion 231b contacts the inner surface of the sidewall portion 222 and the first contact portion 231c contacts the first linear portion of the split spacer 243a.

[0115] The second buffer portion 232 includes a second blade portion 232b and a second contact portion 232c bent relative to the second blade portion 232b. The second blade portion 232b has a fourth end portion 232a. The second buffer portion 232 is disposed such that the second blade portion 232b contacts the inner surface of the sidewall portion 222 and the second contact portion 232c contacts the second linear portion of the split spacer 243g.

[0116] As shown in FIGS. 24A to 24C, first, the first buffer portion 231, the second buffer portion 232, and the connecting portion 244 of the assembly 420 are inserted inside the tire cover 220 and attached to the tire cover 220.

[0117] Next, split spacers 243a to 243g are inserted between first buffer portion 231 and second buffer portion 232. At this time, because first buffer portion 231 and second buffer portion 232 are connected by connecting portion 244, first buffer portion 231 and second buffer portion 232 do not move in the left-right direction away from each other. As a result, the first linear portion of split spacer 243a comes into contact with first contact portion 231c, applying pressure to first blade portion 231b. In addition, the second linear portion of split spacer 243g comes into contact with second contact portion 232c, applying pressure to second blade portion 232b.

[0118] Then, with the assembly 420 attached to the tire cover 220, the two bead portions 223 are attached to the two side surfaces of the rim 212. The tire cover 220 is pressurized outward and pressed against the rim 212. This prevents the tire cover 220 from coming off the rim 212.

[0119] The carcass 225 suppresses outward stress on the connecting portion 244, the central portions of the divided spacers 243a to 243g, the first wing portion 231b, and the second wing portion 232b. As a result, the connecting portion 244, the first wing portion 231b, and the second wing portion 232b are in direct and intimate contact with the inner surface of the tire cover 220, forming a two-layer intimate contact structure. The central portions of the divided spacers 243a to 243g are in intimate contact with the inner surface of the connecting portion 244. As a result, the annular shape of the tire cover 220 is maintained. Furthermore, the first wing portion 231b and the second wing portion 232b push the tire cover 220 outward in the left-right direction, thereby maintaining the shape of the sidewall portion 222 that bulges in the left-right direction.

[0120] When the tire cover 220 and the assembly 420 are assembled to the wheel 210, the third end 231a of the first wing portion 231b is located radially outward of the wheel 210 relative to the first end 223a of the tire cover 220 and is displaceable. Furthermore, the fourth end 232a of the second wing portion 232b is located radially outward of the wheel 210 relative to the second end 223b of the tire cover 220 and is displaceable. In other words, the third airless tire 300 does not include a support that physically connects the assembly 420 to the wheel 210, and the assembly 420 is not physically connected to the wheel 210 and does not come into contact with it. This reduces vibration and noise transmitted from the third airless tire 300 to the vehicle body.

[0121] In the third airless tire 300, the spacer 243 maintains the longitudinal arch structure, thereby supporting the load applied to the third airless tire 300. Furthermore, the first buffer portion 231 and the second buffer portion 232 maintain the transverse arch structure, thereby absorbing the impact applied to the third airless tire 300 and assisting the deflected support portion 240 in restoring its shape.

[0122] The action of forces applied to the third airless tire 300 will be described with reference to Figures 25A to 25D. As shown in Figures 25A and 25D, when an upward external force is applied to the third airless tire 300 at the ground contact point while the tire is running, the annular divided spacers 243a to 243g to which the external force is applied are displaced upward to absorb the external force. The other divided spacers continue to apply downward stress to the carcass 225 to maintain the shape of the tire cover 220. The load applied to the third airless tire 300 is distributed and supported by the divided spacers 243a to 243g.

[0123] In this embodiment, the spacer 243 is divided into multiple divided spacers 243a to 243g, and the divided spacers 243a to 243g are individually displaced to adapt to the road surface shape, maintain the vehicle posture, and increase the contact patch of the third airless tire 300. As shown in Figure 26A, when the vehicle body leans to the right with respect to the road surface, the second blade portion 232b is displaced to the right and expands, and the divided spacers 243a to 243g also lean to the right. As a result, even when the vehicle body leans, the contact patch of the tread portion 221 remains approximately the same as when the vehicle body is not leaned, and reduction in the contact patch of the tread portion 221 is suppressed.

[0124] 26B, when the road surface is inclined so that the right side is higher and the left side is lower, second wing portion 232b is displaced to the right and spreads out. Segment spacers 243a to 243g are positioned successively higher from segment spacer 243a to segment spacer 243g according to the inclination of tread portion 221. This prevents a reduction in the contact area of ​​tread portion 221 even when the road surface is inclined.

[0125] 26C , when the widthwise center portion of the third airless tire 300 runs over a fallen object on the road surface, the center portion of the tread portion 221 deforms and bulges upward. In response to the deformation of the tread portion 221, the central divided spacer 243d and the divided spacers 243c and 243e on either side of it are displaced upward. This prevents a reduction in the contact area of ​​the tread portion 221 even when the third airless tire 300 runs over a fallen object.

[0126] 26D , when the right side of the third airless tire 300 runs over a curb, the right side of the tread 221 deforms and bulges upward. In response to the deformation of the tread 221, the second wing portion 232b displaces upward and spreads to the right, and the divided spacers 243f, g displace upward. This prevents a reduction in the contact area of ​​the tread 221 even when the third airless tire 300 runs over a curb.

[0127] 26E and 26F, when the third airless tire 300 passes over a step, the tread 221 deforms so as to rise upward uniformly in the width direction. In response to the deformation of the tread 221, the first wing 231b displaces upward and spreads to the left, and the second wing 232b displaces upward and spreads to the right. In addition, the divided spacers 243a to 243g displace upward uniformly. This prevents a reduction in the contact area of ​​the tread 221 even when the third airless tire 300 passes over a step.

[0128] 25A and 25B , when an upward external force is applied to the third airless tire 300 at the contact patch, the divided spacers 243a to 243g are displaced forward at the front to release the load, and the first and second wing portions 231b and 232b, which are constrained by the reaction force of the simultaneously extruded carcass 225, are moved closer to each other in the left-right direction. When the dynamic load is removed, the elastic reaction force of the buffer portion 230 causes the wing portions to move apart in the left-right direction and return to their original shape, and at the same time, the deflected spacer 243 is pushed back rearward, restoring the shape of the third airless tire 300. Within the movable range permitted by the inextensible carcass 225, the buffer portion 230 is constrained from moving in the left-right direction, and the divided spacers 243a to 243g are constrained from moving up-down and forward-backward. This allows for both shock absorption and load support.

[0129] As shown in FIGS. 25A and 25C, the rear side of the third airless tire 300 undergoes operations symmetrical to those of the front side of the third airless tire 300 shown in FIG. 25B.

[0130] That is, the divided spacers 243a to 243g receive the reaction force of the carcass 225, maintain the longitudinal arch structure, and support the load applied to the third airless tire 300. The first wing portion 231b and the second wing portion 232b maintain the two-layer close contact structure between the assembly 420 and the tire cover 220, and therefore the lateral arch structure, and absorb impacts applied to the third airless tire 300 while assisting the support portion 240 in restoring its shape when bent.

[0131] 29A and 29B show a pneumatic tire 350 for automobiles according to a reference example. The pneumatic tire 350 is filled with compressed air inside the tire cover 220 instead of the assembly 420. When a temporary dynamic load is applied to the pneumatic tire 350 at its contact point with the ground, the surface pressure at the contact patch increases, and the air at the inflated pressure is pushed out (flows) to other areas. This increases the contact area, reducing the surface pressure. The inflated pressure and the contact pressure at the contact patch (ground pressure) balance, and the cushioning function of the pneumatic tire 350 ceases. When the temporary dynamic load is removed and the only load applied to the pneumatic tire 350 is the static load, the surface pressure at the contact patch further decreases, and the air at the inflated pressure is pushed back (flows) to the recessed area caused by cushioning, supporting the static load. The contact patch then narrows, restoring the original shape of the pneumatic tire 350, where the surface pressure under static load and the inflated pressure balance, thereby restoring the shape of the pneumatic tire 350. The carcass 225 of the tire cover 220 attached to the vehicle has sufficient strength (i.e., reaction force) to withstand inflation or rupture even when filled with air at a load-bearing pressure (safety factor) equal to or greater than the maximum load the vehicle can bear. Because the air is filled at an appropriate pressure that provides a good balance between load support and cushioning, the pneumatic tire 350 maintains a substantially perfect circular shape and supports the load. In other words, the air filled in the pneumatic tire 350 has both a load-supporting function and a cushioning function.

[0132] 3-2. Second Example of Third Airless Tire A third airless tire 300A according to a second example of the third embodiment will be described with reference to Figures 27 and 28. The basic configuration is similar to that of the first example of the third embodiment, and differences will be described below. Note that the same reference numerals as those in the first example of the third embodiment indicate the same configuration, and the preceding description will be referred to.

[0133] A third airless tire 300A according to a second example of the third embodiment includes an assembly 420A instead of the assembly 420. The assembly 420A includes a support portion 240A and a buffer portion 230. The buffer portion 230 includes a first buffer portion 231 and a second buffer portion 232. The support portion 240A includes a connecting portion 244 and either one of a combination of five first spacers 243A and five first casings 245A or a combination of five second spacers 243B and five second casings 245B.

[0134] The first spacer 243A, like the first spacer 43A, is a compression coil spring member and is a ring-shaped compression spring. The first spacer 243A has a circular radial cross section. In an unloaded state, the first spacer 243A has a circumferential length longer than the circumferential length of the first casing 245A. The second spacer 243B, like the second spacer 43B, is a continuous crank leaf spring and is a ring-shaped compression spring. The second spacer 243B has a rectangular radial cross section. In an unloaded state, the second spacer 243B has a circumferential length longer than the circumferential length of the second casing 245B.

[0135] The first casings 245A are formed in an annular shape, are inextensible and flexible, and have openings that open toward the wheels 210. Each of the first casings 245A houses a first spacer 243A in a compressed state through the opening. The first casings 245A have an arc-shaped inner peripheral surface that corresponds to the outer peripheral surface of the first spacer 243A.

[0136] The second casings 245B are formed in an annular shape, are inextensible and flexible, and have openings that open toward the wheels 210. Each of the second casings 245B houses a second spacer 243B in a compressed state through the opening. The second casings 245B have a planar inner peripheral surface that corresponds to the outer peripheral surface of the second spacer 243B.

[0137] 28 , either a first set in which five first casings 245A each house a first spacer 243A, or a second set in which five second casings 245B each house a second spacer 243B, is selected and attached to the connecting portion 244. Then, the assembly 420A is attached to the tire cover 220.

[0138] Then, with the assembly 420A attached to the tire cover 220, the two bead portions 223 are attached to the rim 212. This prevents the tire cover 220 from coming off the rim 212.

[0139] Carcass 225 suppresses outward stress in connecting portion 244, support portion 240A (specifically, five first casings 245A or five second casings 245B), and buffer portion 230 (specifically, first wing portion 231b and second wing portion 232b). As a result, connecting portion 244, first wing portion 231b, and second wing portion 232b are in direct and intimate contact with the inner surface of tire cover 220, forming a two-layer intimate structure.

[0140] In addition, either first casing 245A compressed by the stretching force of first spacer 243A or second casing 245B compressed by the stretching force of second spacer 243B is tightly attached to connecting portion 244, thereby maintaining the annular shape of tire cover 220. Furthermore, first wing portion 231b and second wing portion 232b push tire cover 220 open in the left-right direction, thereby maintaining the shape of sidewall portion 222 that bulges in the left-right direction.

[0141] The spacer of the support portion 240A is configured to be divided into five pieces, so that the load applied to the third airless tire 300A is divided and supported. Furthermore, in response to deformation of the tread portion 221 due to changes in the road surface shape, the spacer at the corresponding position among the five spacers is displaced, adapting to the change in the road surface shape, thereby suppressing a reduction in the contact area of ​​the tread portion 221.

[0142] The support portion 240A includes either a first set of a first spacer 243A and a first casing 245A, or a second set of a second spacer 243B and a second casing 245B, but the number of divisions of the spacer is not limited.

[0143] 3-3. Effects The third embodiment described above in detail provides the same effects as the effects (1) to (3) of the first embodiment and the effects (8) to (11) of the second embodiment. Furthermore, the third airless tire 300A further provides the same effects as the effects (4) to (7) of the first embodiment. Furthermore, the third airless tire 300A provides the following effects.

[0144] (12) In the third airless tire 300A, the first spacer 243A or the second spacer 243B, which has a circumferential length longer than that of the casing, is compressed and housed in the casing, and the casing is attached to the inside of the tire cover 220. This causes the casing, which is pressurized by the elongation force of the first spacer 243A or the second spacer 243B, to come into close contact with the tire cover 220 and maintain that state. As a result, the first spacer 243A or the second spacer 243B can support a load applied to the third airless tire 300A. Furthermore, when the third airless tire 300A receives an impact, the first spacer 243A or the second spacer 243B deforms toward the opening of the casing, thereby absorbing the impact.

[0145] (Summary) Figure 30 shows the configuration, force relationships, and force directions common to the first, second, and third airless tires. As shown in Figure 30, external loads such as the vehicle weight and impact loads are directed inward toward the wheel at the contact patch, but are directed outward in the opposite direction at the horizontal position (half the vertical height) and at the top (symmetrical position of the contact patch) because the external force is released outward by the stress of the annular assembly. Since the stress is a resistance force generated in the assembly that receives the external force, it is directed in the opposite direction to the external force at all positions. The reaction force generated in the non-extensible tire cover is directed inward toward the wheel at all positions because the tire cover is attached and fixed to the wheel rim at the bead portion.

[0146] Generally, forces are transmitted in the following order: pressure (external force) → resistance (stress) → support (reaction force), but the positional relationship is different only at the contact patch of this airless tire. That is, at the contact patch of this airless tire, the order is load (external force) → tire cover (reaction force) → assembly (stress), which is a contradiction compared to typical force transmission. This airless tire resolves this contradiction by utilizing its annular shape. Specifically, the external force received at the contact patch is transferred from the inside to the outside of the airless tire at a position other than the contact patch via the assembly where stress is generated. Furthermore, at a position other than the contact patch, the reaction force generated on the tire cover supports the external force that has moved outward with the back support. Therefore, at a position other than the contact patch, forces are transmitted normally in the following order: external force → stress generated on the assembly → reaction force generated on the tire cover, establishing a force relationship that supports the load.

[0147] Next, the hollow structure will be described. This airless tire has a two-layer annular structure in which a non-shrinkable assembly that generates stress is placed in close contact with the inside of a non-extensible tire cover that generates a reaction force. When a load is applied to the contact patch, the non-shrinkable, flexible assembly is pushed upward by the external force and bends into an elliptical shape in the front-to-rear direction. The assembly is in close contact with the inside of the non-extensible tire cover that generates a reaction force, and the upper part, which is symmetrical to the contact patch, functions as a vertical reaction force, while the horizontal part functions as a horizontal reaction force, creating an arched annular structure. Therefore, this two-layer annular structure enables the hollow structure to support loads.

[0148] Next, we will explain the pillarless structure. At the contact patch, external forces are directed inward toward the wheel, but at this location, no reaction force is present to support the external force. The reaction forces generated by the non-stretchable tire cover are all directed inward, just like a pneumatic tire, due to the bead being set on the wheel rim. Only at the contact patch, where direct loads are applied, are the external and reaction forces directed inward, meaning that there is no structural load support around the contact patch. The non-shrinkable assembly, which generates stress, is closely positioned inside the non-stretchable tire cover, where reaction forces are generated, thereby supporting the load around the entire circumference of this airless tire. The fact that the load is supported despite the reaction force and the external load force generated by the tire cover, which is the only part of the contact patch that comes into contact with the wheel, facing inward, demonstrates the feasibility of the pillarless structure of this airless tire. The effect of this pillarless structure is that the tire cover, which is in contact with the wheel, does not generate resistance to the load, so vibrations and noise generated at the contact patch during driving are less likely to be transmitted to the vehicle body.

[0149] This airless tire has a tensile structure similar to that of a pneumatic tire. The inextensible tire cover attached to the wheel rim encases the assembly that transfers the load, confining and suppressing stress inside the reaction force, thereby achieving a tensile structure. In this tensile structure, the reaction force due to the elasticity of the buffer section pushes the sidewall section apart, tightly sealing the two layers of the tire cover and assembly, centering the wheel and supporting the load. Furthermore, by transferring the load applied to the contact patch to the assembly and tightly sealing the entire circumference of the tire cover where the reaction force is generated, surface pressure is reduced, allowing for a more compact (lightweight) assembly. Therefore, the double-wheel structure and two-layer tight-fitting structure of the annular tire cover and assembly in this airless tire make a pillarless hollow structure possible.

Claims

1. An assembly for an airless tire configured to be disposed around the entire circumferential direction of a tire cover inside the tire cover, the tire cover having first and second ends and being inextensible, which are attached to the rim of a tire wheel, the assembly comprising: a first edge portion and a second edge portion formed in a circular ring shape and extending along the circumferential direction of the circular ring shape; a support portion that is inextensible and flexible and disposed so as to be in close contact with the inner surface of the tread portion of the tire cover; and a buffer portion that is elastic and flexible and disposed so as to be in close contact with the inner surface of the side portion of the tire cover, the support portion and the buffer portion being either an integral member or separate members, the buffer portion including a first buffer portion extending from the first edge portion toward the first end and a second buffer portion extending from the second edge portion toward the second end over the entire circumference of the circular ring shape, the first buffer portion having a third end positioned radially outward of the wheel and displaceable relative to the first end, The assembly for an airless tire, wherein the second buffer portion has a fourth end portion positioned radially outward from the second end portion and displaceably disposed.

2. The airless tire assembly according to claim 1, wherein the support portion is a band-shaped member rolled into an annular shape and has a width along the width direction of the tire cover and a thickness along the radial direction of the tire cover, the support portion and the buffer portion are an integral member, the first edge portion is one of two ends along the circumferential direction of the band-shaped member, and the second edge portion is the other of the two ends.

3. The airless tire assembly according to claim 1, wherein the first buffer section and the second buffer section have cutouts formed at regular intervals.

4. The airless tire assembly according to claim 1, wherein the first buffer section and the second buffer section each include a plurality of stacked sheet members, each of the plurality of sheet members included in the first buffer section has the third end, each of the plurality of sheet members included in the second buffer section has the fourth end, the plurality of sheet members included in the first buffer section have mutually different lengths from the first edge section to the third end, and the plurality of sheet members included in the second buffer section have mutually different lengths from the second edge section to the fourth end.

5. The airless tire assembly according to claim 1, wherein the support portion is a compression spring member having a circular ring shape, and the circumferential length of the support portion in an unloaded state before being attached to the tire cover is longer than the circumferential length of the tire cover.

6. The airless tire assembly according to claim 1, wherein the support section and the buffer section are separate members, and the support section includes a plurality of divided members arranged in the width direction of the tire.

7. The airless tire assembly according to claim 6, wherein each of the plurality of divided members is formed in an arch shape including a central portion in contact with the inner surface of the tire cover, and a first straight portion and a second straight portion extending from each of both ends of the central portion, the first straight portion of one of the plurality of divided members being arranged to be in contact with the first buffer portion, the second straight portion of another of the plurality of divided members being arranged to be in contact with the second buffer portion, and the first straight portion of the remaining divided members being arranged to be in contact with the second straight portion of another adjacent divided member.

8. The airless tire assembly according to claim 1, wherein the support portion and the buffer portion are separate members, the support portion is formed in an arch shape including a central portion that contacts the inner surface of the tire cover and straight portions that extend from both ends of the central portion, one of the straight portions being positioned so as to contact the first buffer portion, and the other of the straight portions being positioned so as to contact the second buffer portion.

9. The airless tire assembly according to claim 1, wherein the support portion and the buffer portion are separate members, the first buffer portion has the third end and includes a first wing portion arranged in close contact with the inner surface of the side portion, and a first contact portion bent relative to the first wing portion and arranged in contact with the support portion, and the second buffer portion has the fourth end and includes a second wing portion arranged in close contact with the inner surface of the side portion, and a second contact portion bent relative to the second wing portion and arranged in contact with the support portion.

10. The airless tire assembly according to claim 1, wherein the support portion further includes a connecting portion formed of a non-extensible and flexible material, the connecting portion connecting the first buffer portion and the second buffer portion so that the first buffer portion and the second buffer portion are in close contact with the inner surface of the side portion.

11. The airless tire assembly according to claim 1, wherein the support portion includes one or more casings arranged in the width direction of the tire cover and one or more compression spring members housed in each of the casings, each of the casings being formed in an annular shape and having inextensibility and flexibility and an opening that opens toward the wheel, and each of the compression spring members being formed in an annular shape with a circumferential length longer than that of the casing.

12. An airless tire comprising: a tire cover having first and second ends and inextensibility attached to a wheel rim; and an assembly for an airless tire configured to be arranged around the entire circumferential direction of the tire cover, wherein the assembly is formed in an annular shape and comprises first and second edge portions along the circumferential direction of the annular shape; a support portion that is incontractible and flexible and arranged to be in close contact with the inner surface of a tread portion of the tire cover; and a buffer portion that is elastic and flexible and arranged to be in close contact with the inner surface of a side portion of the tire cover, wherein the support portion and the buffer portion are integral or separate members, and the buffer portion includes a first buffer portion that extends from the first edge portion toward the first end and a second buffer portion that extends from the second edge portion toward the second end over the entire circumference of the annular shape, and the first buffer portion has a third end that is positioned radially outward of the wheel and displaceable relative to the first end, The second buffer portion has a fourth end portion that is positioned radially outward from the second end portion and is displaceable.

13. An airless tire as described in claim 12, wherein the support portion is a band-shaped member rolled into an annular shape, having a width along the width direction of the tire cover and a thickness along the radial direction of the tire cover, the support portion and the buffer portion are an integral member, the first edge portion is one of two ends along the circumferential direction of the band-shaped member, and the second edge portion is the other of the two ends.

14. The airless tire according to claim 12, wherein the first buffer portion and the second buffer portion have cutouts formed at regular intervals.

15. An airless tire as described in claim 12, wherein the first buffer section and the second buffer section each include a plurality of stacked sheet members, wherein each of the plurality of sheet members included in the first buffer section has the third end, wherein each of the plurality of sheet members included in the second buffer section has the fourth end, wherein the plurality of sheet members included in the first buffer section have mutually different lengths from the first edge section to the third end, and wherein the plurality of sheet members included in the second buffer section have mutually different lengths from the second edge section to the fourth end.

16. The airless tire according to claim 12, wherein the support portion is a compression spring member having a circular ring shape, and the circumferential length of the support portion in an unloaded state before being attached to the tire cover is longer than the circumferential length of the tire cover.

17. The airless tire according to claim 12, wherein the support portion and the buffer portion are separate members, and the support portion includes a plurality of divided members arranged in the width direction of the tire.

18. The airless tire according to claim 17, wherein each of the plurality of divided members is formed in an arch shape including a central portion in contact with the inner surface of the tire cover and a first straight portion and a second straight portion extending from each of both ends of the central portion, the first straight portion of one of the plurality of divided members is arranged to be in contact with the first buffer portion, the second straight portion of another of the plurality of divided members is arranged to be in contact with the second buffer portion, and the first straight portion of the remaining divided members of the plurality of divided members is arranged to be in contact with the second straight portion of another adjacent divided member.

19. An airless tire as described in claim 12, wherein the support portion and the buffer portion are separate members, the support portion is formed in an arch shape including a central portion that contacts the inner surface of the tire cover and straight portions that extend from both ends of the central portion, one of the straight portions being positioned so as to contact the first buffer portion, and the other of the straight portions being positioned so as to contact the second buffer portion.

20. An airless tire as described in claim 12, wherein the support portion and the buffer portion are separate members, the first buffer portion has the third end and includes a first wing portion arranged in close contact with the inner surface, and a first contact portion bent relative to the first wing portion and arranged in contact with the support portion, and the second buffer portion has the fourth end and includes a second wing portion arranged in close contact with the inner surface, and a second contact portion bent relative to the second wing portion and arranged in contact with the support portion.

21. The airless tire according to claim 12, wherein the support portion further includes a connecting portion formed of a non-extensible and flexible material, the connecting portion connecting the first buffer portion and the second buffer portion so that the first buffer portion and the second buffer portion are in close contact with the inner surface of the tire cover.

22. The airless tire according to claim 12, wherein the support portion includes one or more casings arranged in the width direction of the tire cover and one or more compression spring members housed in each of the casings, each of the casings being formed in an annular shape and having inextensibility and flexibility and an opening that opens toward the wheel, and each of the compression spring members being formed in an annular shape with a circumferential length longer than that of the casing.

Images