Non-pneumatic tires

Abstract

It provides a highly reliable non-pneumatic tire equipped with multiple support structures. [Solution] The tire 1 comprises a tread 50 and a support structure 10, and is a non-pneumatic tire in which a plurality of the support structures are joined together in the tire axial direction, and each support structure 10 comprises a connecting body 40 that connects an inner annular portion 20 and an outer annular portion 30, and the connecting body 40 has a first wall portion 41, a second wall portion 42 and a connecting portion 43 that connects the first wall portion 41 and the second wall portion 42, and the non-pneumatic tire has an inner joining portion 21 to which the inner annular portion 20 is joined and an outer joining portion 31 to which the outer annular portion 30 is joined, and the inner joining portion 21 and the outer joining portion 31 have convex portions 22A, 22B that protrude to one side in the tire axial direction and concave portions 23A, 23B that are recessed to the other side in the tire axial direction when viewed from the outer diameter side or the inner diameter side of the tire, and the convex portions 22A, 22B and concave portions 23A, 23B are arranged alternately in the tire circumferential direction.

Description

Technical Field

[0001] The present disclosure relates to non-pneumatic tires.

Background Art

[0002] In recent years, non-pneumatic tires that do not cause problems such as punctures and do not require air pressure adjustment have been developed. As non-pneumatic tires, generally, a resin support structure in which an inner annular portion and an outer annular portion arranged coaxially with each other are integrally connected via a plurality of spokes arranged in the tire circumferential direction, and a tread rubber provided on the outer peripheral surface of the outer annular portion of this support structure are provided.

[0003] Also, a non-pneumatic tire in which a plurality of support structures (spoke disks) are arranged side by side in the tire axial direction is known (for example, see Patent Document 1). In the non-pneumatic tire of Patent Document 1, the plurality of support structures are adhered to a shear band provided on the outer peripheral side thereof, and the support structures are adhered to a rim provided on the inner peripheral side thereof.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, increasing the reliability of non-pneumatic tires by adhering a plurality of support structures in the tire axial direction has not been done.

[0006] An object of the present disclosure is to provide a non-pneumatic tire having a plurality of support structures and high reliability.

Means for Solving the Problems

[0007] The pneumatic tire of the present disclosure is a non-pneumatic tire comprising a tread and a support structure, the support structure being annular and comprising an inner annular portion, an outer annular portion arranged coaxially with the inner annular portion on the outer circumference of the inner annular portion, and a connecting body connecting the inner annular portion and the outer annular portion, the connecting body having, in a cross-sectional view in the tire axial direction, a first wall portion extending to one side in the tire axial direction as it moves from the outer annular portion toward the inner annular portion, and a second wall portion extending to the one side as it moves from the inner annular portion toward the outer annular portion The support structure has a second wall portion and a connecting portion that connects the first wall portion and the second wall portion, and a plurality of the support structures are joined together in the tire axial direction, and has an inner joint portion to which the inner annular portion is joined and an outer joint portion to which the outer annular portion is joined, and at least one of the inner joint portion and the outer joint portion has a convex portion that protrudes to one side in the tire axial direction and a concave portion that is recessed to the other side in the tire axial direction when viewed from the outer diameter side or the inner diameter side of the tire, and the convex portion and the concave portion are arranged alternately in the tire circumferential direction. [Effects of the Invention]

[0008] According to this disclosure, a highly reliable non-pneumatic tire can be provided, comprising multiple support structures. [Brief explanation of the drawing]

[0009] [Figure 1] This is a perspective view showing a first embodiment of the non-pneumatic tire 1 according to the present disclosure. [Figure 2] This is a perspective view showing the state after cutting off the non-pneumatic tire 1 at the position indicated by arrow AA in Figure 1. [Figure 3] Figure 2 is an enlarged cross-sectional view of the tire in the axial direction. [Figure 4] This is a perspective view showing the support structure 10 of the first embodiment. [Figure 5] This is a partial unfolded view of the support structure 10 unfolded in the tire circumferential direction C to explain the joint between support structure 10A and support structure 10B. [Figure 6] This is a perspective view showing the support structure 10 of the second embodiment. [Figure 7] This is a cross-sectional view of the tire axial direction of the tire 1 of the third embodiment, similar to Figure 3 of the first embodiment. [Figure 8] This is a partial unfolded view of the joint between support structure 10A and support structure 10B, unfolded in the tire circumferential direction C. [Figure 9] This is a cross-sectional view of the tire axial direction of the tire 1D of the fourth embodiment, similar to Figure 3 of the first embodiment. [Figure 10] This is a partial exploded view of the joint between the support structure 10A and the support structure 10B of the fourth embodiment, unfolded in the tire circumferential direction C. [Figure 11] This is a partially unfolded view of the joint between the support structure 10A and the support structure 10B in the modified form of the fourth embodiment, unfolded in the tire circumferential direction C. [Figure 12] This figure shows the deformed shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire. [Figure 13] This figure shows the deformed shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire. [Modes for carrying out the invention]

[0010] The following describes one embodiment for implementing this disclosure with reference to drawings and other documents.

[0011] (First Embodiment) Figure 1 is a perspective view showing a first embodiment of the non-pneumatic tire 1 according to this disclosure. Figure 2 is a perspective view showing the non-pneumatic tire 1 cut at the position of arrow AA in Figure 1. Figure 3 is an enlarged cross-sectional view of the tire axial direction from the cross-section in Figure 2. Note that the following figures, including Figure 1, are schematic representations, and the size and shape of each part are exaggerated or omitted as appropriate for ease of understanding. In the following description, specific numerical values, shapes, materials, etc., will be shown, but these can be changed as appropriate. Note that coordinates to indicate the orientation of the non-pneumatic tire 1 are also shown in each figure. The X axis indicates the tire radial direction, and the Y axis indicates the tire axial direction (tire width direction). Arrow C indicates the tire circumferential direction. The tire circumferential direction C is the direction around the tire rotation axis and is the same direction as the direction in which the non-pneumatic tire 1 rotates. The tire radial direction X is the direction perpendicular to the tire rotation axis. The tire axial direction Y is the direction parallel to the tire rotation axis. Figure 3 also shows the tire equatorial plane E. The tire equatorial plane E shown in Figure 3 is a plane perpendicular to the tire rotation axis and is located at the center of the non-pneumatic tire 1 in the tire axial direction Y. The non-pneumatic tire 1 of the first embodiment comprises a support structure 10 and a tread 50.

[0012] The support structure 10 supports the load from the vehicle. The support structure 10 has an inner annular portion 20, an outer annular portion 30 arranged coaxially with the inner annular portion 20 on the outer circumference side of the inner annular portion 20 (outside the tire radial direction X), and a connecting body 40 that connects the inner annular portion 20 and the outer annular portion 30. In this embodiment, the support structure 10 is configured in an annular (ring) shape when viewed from the side of the non-pneumatic tire 1, and has a continuous configuration in the circumferential direction. The support structure 10 may also be configured to be divided into multiple parts in the circumferential direction when viewed from the side of the non-pneumatic tire 1.

[0013] The support structure 10 is made of resin. The resin constituting the support structure 10 is not particularly limited, and examples thereof include thermosetting resins such as urethane resin, epoxy resin, and phenolic resin, thermosetting elastomers, etc., and thermoplastic resins such as polyethylene, polyurethane, polyester, polyamide, etc., and thermoplastic elastomers. The resin constituting the support structure 10 preferably contains one or more additives selected from the group consisting of an ultraviolet blocker, an ultraviolet absorber, an antioxidant, and a light stabilizer in order to ensure the durability of the support structure 10.

[0014] Note that the thicknesses of the inner annular portion 20 and the outer annular portion 30 are dimensions in the tire diameter direction X. Also, the widths of the inner annular portion 20 and the outer annular portion 30 are dimensions in the tire axial direction Y.

[0015] The inner annular portion 20 is an annular portion along the tire circumferential direction C that constitutes the inner peripheral portion of the non-pneumatic tire 1. The thickness and width of the inner annular portion 20 are set to be constant in order to improve uniformity. A tire wheel (not shown) is disposed in the space on the inner peripheral side of the inner annular portion 20. The inner peripheral portion of the inner annular portion 20 is fitted and mounted on the outer peripheral portion of the rim of the tire wheel. When the inner annular portion 20 is mounted on the rim, the non-pneumatic tire 1 is mounted on the tire wheel. The inner peripheral surface of the inner annular portion 20 may be provided with a fitting portion constituted by a convex portion, a groove, etc. for fitting with the rim.

[0016] The inner annular portion 20 transmits the rotation of the tire wheel to the connecting body 40 and the outer annular portion 30. The thickness of the inner annular portion 20 is determined from the viewpoint of sufficiently transmitting the rotational force to the connecting body 40 while achieving weight reduction and durability. The thickness of the inner annular portion 20 is not particularly limited.

[0017] The inner diameter of the inner annular portion 20 is determined according to the dimensions of the rim of the tire wheel on which the non-pneumatic tire 1 is mounted, the use of the vehicle, etc. For example, when assuming replacement with a general pneumatic tire, the inner diameter of the inner annular portion 20 may be, for example, dimensions such as 250 mm or more and 500 mm or less, but is not limited thereto.

[0018] The width of the inner annular portion 20 is determined appropriately according to the intended use of the vehicle on which the non-pneumatic tire 1 is mounted, the length of the axle, etc. As will be described in detail later, the non-pneumatic tire 1 in this embodiment is configured by arranging two support structures 10 (10A, 10B) side by side in the direction of the tire axis Y. Therefore, the width of each inner annular portion 20 is determined to match the final width of the non-pneumatic tire 1 when multiple structures are combined. For example, assuming a replacement for a typical pneumatic tire, the width of the non-pneumatic tire 1 may be between 100 mm and 300 mm. In this case, the width of each inner annular portion 20 of the two side by side support structures 10 can be exemplified as between 50 mm and 150 mm. Note that these widths are merely examples and are not limited to these.

[0019] The outer annular portion 30 is an annular part along the tire circumferential direction C that constitutes the outer circumference of the non-pneumatic tire 1. The outer annular portion 30 is arranged concentrically with the inner annular portion 20 on its outer circumference side. The thickness and width of the outer annular portion 30 are set to be constant in order to improve uniformity.

[0020] The outer annular portion 30 transmits the rotation of the inner annular portion 20 and the connecting body 40 to the road surface via the tread 50. The thickness of the outer annular portion 30 is determined from the viewpoint of achieving weight reduction and durability while satisfying the function of sufficiently transmitting rotational force from the connecting body 40 to the road surface.

[0021] The inner diameter of the outer annular portion 30 is determined appropriately according to the dimensions of the rim of the tire wheel on which the non-pneumatic tire 1 is mounted, the intended use of the vehicle, etc. For example, when considering a replacement for a general pneumatic tire, the inner diameter of the outer annular portion 30 may be between 420 mm and 750 mm, but is not limited to this.

[0022] The width of the outer annular portion 30 is determined appropriately according to the intended use of the vehicle on which the non-pneumatic tire 1 is fitted, and specifically, it is the same as the width of the inner annular portion 20 described above, so a detailed explanation is omitted. The width of the outer annular portion 30 may be the same as the width of the inner annular portion 20, or it may be different.

[0023] The connecting body 40 has a first wall portion 41, a second wall portion 42, and a connecting portion 43, and connects the inner annular portion 20 and the outer annular portion 30.

[0024] In the tire axial cross-sectional view shown in Figure 3, the first wall portion 41 extends to one side in the tire axial direction (to the left in the Figure for the support structure 10 located on the left side in Figure 3) as it moves from the outer annular portion 30 toward the inner annular portion 20. In this embodiment, the first wall portion 41 extends in a direction that forms an angle of approximately 45° with respect to the outer annular portion 30.

[0025] In the tire axial cross-sectional view shown in Figure 3, the second wall portion 42 extends in the same direction as the first wall portion 41 as it extends from the inner annular portion 20 toward the outer annular portion 30 (to the left in the case of the support structure 10 located on the left side in Figure 3). In this embodiment, the second wall portion 42 extends in a direction in which it forms an angle of approximately 45 with respect to the inner annular portion 20.

[0026] The connecting portion 43 is the part that connects the first wall portion 41 and the second wall portion 42. The connecting portion 43 has an inner edge 431 and an outer edge 432. The inner edge 431 is the side on which the first wall portion 41 and the second wall portion 42 form an inferior angle (an angle smaller than 180°) in a cross-sectional view in the tire axial direction. The outer edge 432 is the side on which the first wall portion 41 and the second wall portion 42 form a superior angle (an angle larger than 180°) in a cross-sectional view in the tire axial direction.

[0027] The inner edge 431 includes a connecting recess 433 that curves inward from the inner edge 431 towards the outer edge 432 in a cross-sectional view in the axial direction of the tire. In this embodiment, the connecting recess 433 is configured as a U-shaped area 433b that includes a curved area 433a. The shape of the connecting recess 433 is not limited to a U-shape, and may consist only of a curved shape. The curved area 433a may also be an arc shape.

[0028] Furthermore, in a cross-sectional view in the tire axial direction, the thickness of the connecting portion 43 changes as it moves from the bottom of the connecting recess 433 toward the first wall portion 41, and as it moves from the bottom of the connecting recess 433 toward the second wall portion 42. This configuration allows for control of the amount of stress dispersion, which will be described later.

[0029] A curved area 434 is provided at a position opposite the connecting recess 433 of the outer edge 432. The curved area 434 may also be in the shape of a circular arc.

[0030] Furthermore, in the non-pneumatic tire 1 of this embodiment, the support structures 10 are arranged symmetrically with respect to the tire equatorial plane E as the plane of symmetry. More specifically, in the non-pneumatic tire 1 of this embodiment, two support structures 10 are arranged facing each other on the inner edge 431 side.

[0031] The tread 50 constitutes the outermost part of the non-pneumatic tire 1. The tread 50 is provided on the outer surface of the outer annular portion 30 and extends along the tire circumferential direction C. The tread 50 has a tread surface 51 on its outer surface that contacts the road surface. The tread surface 51 of the tread 50 is provided with a tread pattern formed by multiple grooves and flat areas, similar to conventional pneumatic tires.

[0032] Tread 50 is composed of a rubber composition for treads. The rubber composition for treads may include, for example, natural rubber and carbon black, and may further contain sulfur, silica, etc. Here, the rubber composition for treads may include synthetic rubber such as polyisoprene rubber or styrene-butadiene rubber together with natural rubber, or in place of natural rubber.

[0033] The tread 50 is bonded to the outer circumferential surface of the outer annular portion 30, for example, by a vulcanizing adhesive. This results in a non-pneumatic tire 1 comprising the support structure 10 and the tread 50. The tread 50 may also be composed of multiple vulcanized rubber layers with different components and properties laminated together (for example, two or three layers).

[0034] Furthermore, in this embodiment, one tread 50 is provided for each support structure 10. Therefore, in this embodiment, two treads 50 are arranged side by side in the tire axial direction Y.

[0035] In this embodiment, the support structure 10 has a connecting body 40 that connects the inner annular portion 20 and the outer annular portion 30, with the first wall portion 41 and the second wall portion 42 connected by a connecting portion 43. This configuration allows the connecting body 40 to operate like intersecting leaf springs in a cross-sectional view in the tire axial direction. Therefore, the connecting body 40 can deform to mitigate external forces acting in the tire radial direction, thereby reducing the external forces transmitted to the axle. Furthermore, the connecting body 40 can also mitigate axial forces acting on the non-pneumatic tire 1 when the steering wheel is turned, etc., by deforming. Thus, in this embodiment, the non-pneumatic tire 1 can effectively absorb a portion of the external forces with the connecting body 40. For this reason, when the vehicle is running, external forces repeatedly act on the connecting body 40, making the durability of the connecting body 40 important.

[0036] In this embodiment, in order to increase the durability of the connecting body 40, the configuration is designed to distribute the stress acting on the connecting body 40. Specifically, by providing a connecting recess 433 on the inner edge 431 of the connecting portion 43, the stress in the support structure 10 is distributed and stress concentration is mitigated. Furthermore, since this connecting recess 433 is configured as a U-shaped area 433b that includes a curved area 433a, the effect of stress distribution is further enhanced.

[0037] Figure 4 is a perspective view showing the support structure 10 of the first embodiment. Figure 5 is a partially unfolded view of the support structure 10 unfolded in the tire circumferential direction C to explain the joint between support structure 10A and support structure 10B. Figure 5 shows the form before support structure 10A and support structure 10B are joined. Also, although Figure 5 mainly shows the inner joint 21, the outer joint 31 with a similar configuration is also shown with corresponding reference numerals in parentheses. The non-pneumatic tire 1 of this embodiment has a configuration in which two support structures 10 (10A, 10B) are arranged side by side in the direction of the tire axis Y. The support structures 10 arranged side by side in this embodiment are two identical shapes, but for ease of understanding, they will be described as support structure (first support structure) 10A and support structure (second support structure) 10B.

[0038] In this embodiment, the support structure 10 consists of a support structure 10A and a support structure 10B arranged side by side, with the support structure 10A and the support structure 10B joined together. The portion where the inner annular portions 20 are joined together will be referred to as the inner joint portion 21, and the portion where the outer annular portions 30 are joined together will be referred to as the outer joint portion 31.

[0039] (Inner joint 21) The support structure 10A has a protrusion 22A and a recess 23A at the inner joint 21 when viewed from the inner diameter side of the tire. The protrusion 22A projects to one side in the tire axial direction (the front side in the tire axial direction in Figure 4). The recess 23A is recessed to the other side in the tire axial direction (the back side in the tire axial direction in Figure 4).

[0040] The other support structure 10B, when viewed from the inner diameter side of the tire, also has a protrusion 22B and a recess 23B on its inner joint portion 21, similar to the support structure 10A. The protrusion 22B projects to the other side in the tire axial direction (the far side in the tire axial direction in Figure 4). The recess 23B is recessed to one side in the tire axial direction (the near side in the tire axial direction in Figure 4).

[0041] The shape of the protrusion 22A of the support structure 10A matches the shape of the recess 23B of the support structure 10B. Similarly, the shape of the recess 23A of the support structure 10A matches the shape of the protrusion 22B of the support structure 10B. The protrusions 22A, 22B and the recesses 23A, 23B are arranged alternately and periodically in the tire circumferential direction C. In the tire 1 of this embodiment, the shape of the inner joint portion 21 when unfolded in the tire circumferential direction C is a wave-like shape with curves.

[0042] Adhesive is applied to the joint surface of the inner joint 21, and the support structure 10A and the support structure 10B are joined (bonded) together. Because this joint surface has an uneven shape, the joint area of ​​the inner joint 21 can be increased, and the support structure 10A and the support structure 10B can be joined more strongly. In addition, because the inner joint 21 is configured in a wave shape, localized stress concentration at the inner joint 21 can be suppressed.

[0043] Furthermore, the period in which the convex portions 22A, 22B and the concave portions 23A, 23B are arranged is preferably 1.3% to 25% of the total circumference at the position where the convex portions 22A, 22B and the concave portions 23A, 23B are arranged. By having the pitch within the above range, the relative positions of the support structure 10A and the support structure 10B are restricted, thereby suppressing misalignment of the relative positions of the support structure 10A and the support structure 10B, as well as abnormal noise and wear damage caused by friction during rolling. Moreover, the height difference between the convex portion 22A and the concave portion 23A in the tire axial direction, and the height difference between the convex portion 22B and the concave portion 23B in the tire axial direction, is preferably 30% to 80% of the total width in the tire axial direction. The height difference being within the above range restricts the relative positions of support structure 10A and support structure 10B, thereby more effectively suppressing misalignment of the relative positions of support structure 10A and support structure 10B, and the resulting noise and wear damage caused by friction during rolling. Furthermore, it is desirable that the inner joint portion 21 does not overlap with the second wall portion 42 when viewed from the tire radial direction. This is because if the inner joint portion 21 is in a position that overlaps with the second wall portion 42 when viewed from the tire radial direction, a part of the second wall portion 42 may not be able to be formed, which may affect the function of absorbing external forces.

[0044] At the inner joint 21, the shapes of the support structure 10A and the support structure 10B match and are joined. The inner joint 21 is provided in an annular shape along the tire circumferential direction C. Therefore, it is possible to suppress misalignment of the relative positions of the support structure 10A and the support structure 10B in the direction along the tire circumferential direction C. Furthermore, in the tire radial direction X, the relative positions are restricted by the engagement of the convex portion 22A and the concave portion 23B, or the engagement of the concave portion 23A and the convex portion 22B, in almost all tire radial directions, thereby suppressing misalignment of the relative positions of the support structure 10A and the support structure 10B. In other words, when joining the support structure 10A and the support structure 10B, they can be joined at the appropriate relative position naturally due to the concave and convex shapes of the inner joint 21, without the need to restrict their position with jigs or other tools.

[0045] (Outer joint 31) The support structure 10A has a protrusion 32A and a recess 33A on the outer joint portion 31 when viewed from the outer diameter side of the tire. The protrusion 32A projects to one side in the tire axial direction (the front side in the tire axial direction in Figure 4). The recess 33A is recessed to the other side in the tire axial direction (the back side in the tire axial direction in Figure 4).

[0046] The other support structure 10B, when viewed from the outer diameter side of the tire, also has a protrusion 32B and a recess 33B on its outer joint portion 31, similar to the support structure 10A. The protrusion 32B projects to the other side in the tire axial direction (the far side in the tire axial direction in Figure 4). The recess 33B is recessed to one side in the tire axial direction (the near side in the tire axial direction in Figure 4).

[0047] The shape of the protrusion 32A of the support structure 10A matches the shape of the recess 33B of the support structure 10B. Similarly, the shape of the recess 33A of the support structure 10A matches the shape of the protrusion 32B of the support structure 10B. The protrusions 32A, 32B and the recesses 33A, 33B are arranged alternately and periodically in the tire circumferential direction C. In the tire 1 of this embodiment, the shape of the outer joint portion 31 when unfolded in the tire circumferential direction C is a wave-like shape with curves.

[0048] Adhesive is applied to the joint surface of the outer joint 31, and the support structure 10A and the support structure 10B are joined (bonded) together. Because this joint surface has an uneven shape, the joint area of ​​the outer joint 31 can be increased, and the support structure 10A and the support structure 10B can be joined more strongly. In addition, because the outer joint 31 is configured in a wave shape, localized stress concentration at the outer joint 31 can be suppressed.

[0049] Furthermore, the period in which the convex portions 32A, 32B and concave portions 33A, 33B are arranged is preferably 1.3% to 25% of the total circumference length at the position where the convex portions 32A, 32B and concave portions 33A, 33B are arranged. In addition, the height difference between the convex portion 32A and concave portion 33A in the tire axial direction, and the height difference between the convex portion 32B and concave portion 33B in the tire axial direction, is preferably 30% to 80% of the total width in the tire axial direction. Moreover, it is preferable that the outer joint portion 31 does not overlap with the first wall portion 41 when viewed from the tire radial direction. This is because if the outer joint portion 31 is located in a position that overlaps with the first wall portion 41 when viewed from the tire radial direction, a part of the first wall portion 41 may not be formed, which may affect the function of absorbing external forces.

[0050] At the outer joint 31, the shapes of the support structure 10A and the support structure 10B are joined together by matching. The outer joint 31 is provided in an annular shape along the tire circumferential direction C. Therefore, it is possible to suppress misalignment of the relative positions of the support structure 10A and the support structure 10B in the direction along the tire circumferential direction C. Furthermore, in the tire radial direction X, the relative positions are restricted by the engagement of the convex portion 32A and the concave portion 33B, or the engagement of the concave portion 33A and the convex portion 32B, in almost all tire radial directions, thereby suppressing misalignment of the relative positions of the support structure 10A and the support structure 10B. In other words, when joining the support structure 10A and the support structure 10B, they can be joined at the appropriate relative position naturally due to the concave and convex shapes of the outer joint 31, without the need to restrict their position with jigs or other tools.

[0051] In this embodiment, since the connecting body 40 of the support structure 10 is curved in the tire axial cross-section, it is conceivable that the force acting in the tire axial direction may increase due to the load acting on the tread 50. Therefore, in the tire 1 of this embodiment, it is conceivable that the force that pulls apart the inner joint 21 or the outer joint 31 of the support structure 10 may increase, so it is desirable to increase the joint strength at these joints.

[0052] In the tire 1 of the first embodiment, the inner joint portion 21 and the outer joint portion 31 are provided with protrusions 22A, 22B and recesses 23A, 23B, and protrusions 32A, 32B and recesses 33A, 33B, respectively. Therefore, the joint strength can be increased in both the inner joint portion 21 and the outer joint portion 31, thereby increasing reliability. Thus, according to the tire 1 of the first embodiment, a highly reliable non-pneumatic tire 1 equipped with multiple support structures 10 can be provided.

[0053] (Second Embodiment) Figure 6 is a perspective view showing the support structure 10 of the second embodiment. The tire 1B of the second embodiment (the entire tire 1B is not shown) is the same as that of the first embodiment, except that the shape of the inner joint 21 and the outer joint 31 of the support structure 10 differs from that of the first embodiment. Therefore, the same reference numerals are used for parts that perform the same function as those of the first embodiment described above, and redundant explanations are omitted as appropriate.

[0054] The inner joint portion 21 of the second embodiment does not have convex and concave portions like the first embodiment, and is joined by planes parallel to the equatorial plane E. On the other hand, the outer joint portion 31 of the second embodiment has convex portions 32A, 32B and concave portions 33A, 33B, but differs from the first embodiment in that the shape of the outer joint portion 31 when unfolded in the tire circumferential direction C is a roughly rectangular wave shape composed of straight line segments.

[0055] In the second embodiment as well, the outer joint portion 31 has convex portions 32A, 32B and concave portions 33A, 33B, so a highly reliable non-pneumatic tire 1 can be provided, similar to the first embodiment. Furthermore, since the outer joint portion 31 has a roughly rectangular wave shape, the relative positions of the support structure 10A and the support structure 10B are restricted, and misalignment of the relative positions of the support structure 10A and the support structure 10B, as well as abnormal noise and damage due to friction during rolling, can be suppressed. In addition, since the inner joint portion 21 has a simple shape, manufacturing can be made easy.

[0056] (Third embodiment) Figure 7 is a cross-sectional view in the tire axial direction showing the tire 1 of the third embodiment in the same manner as in Figure 3 of the first embodiment. Figure 8 is a partially unfolded view of the joint between the support structure 10A and the support structure 10B in the tire circumferential direction C. In Figure 8, the inner joint 21 is mainly shown, but the outer joint 31, which has a similar configuration, is also shown with corresponding reference numerals in parentheses. The tire 1C of the third embodiment is the same as the first embodiment except that it includes adhesive grooves 25 and 35 and adhesive 60. Therefore, parts that perform the same function as those of the first embodiment described above are given the same reference numerals, and redundant explanations are omitted as appropriate.

[0057] The tire 1C of the third embodiment is further provided with adhesive grooves 25, adhesive grooves 35, and adhesive 60 compared to the tire 1 of the first embodiment.

[0058] The adhesive groove 25 is located in the inner annular portion 20 and extends in the circumferential direction of the tire, overlapping the convex portions 22A and 22B and the concave portions 23A and 23B. In this embodiment, the adhesive groove 25 has a substantially triangular cross-sectional shape in the tire axial cross-section. However, the cross-sectional shape of the adhesive groove 25 may be substantially rectangular or substantially semicircular, and can be changed as appropriate. The adhesive groove 25 is filled with adhesive 60.

[0059] The adhesive groove 35 is located in the outer annular portion 30 and extends in the circumferential direction of the tire, overlapping the convex portions 32A and 32B and the concave portions 33A and 33B. In this embodiment, the adhesive groove 35 has a substantially triangular cross-sectional shape in the axial cross-section of the tire. However, the cross-sectional shape of the adhesive groove 35 may be substantially rectangular or substantially semicircular, and can be changed as appropriate. The adhesive groove 35 is filled with adhesive 60.

[0060] According to the tire 1C of the third embodiment, since adhesive grooves 25 and 35 into which adhesive 60 is filled are provided, the bond between the support structure 10A and the support structure 10B can be made stronger, and reliability can be further enhanced.

[0061] (Fourth Embodiment) Figure 9 is a cross-sectional view of the tire axial direction of the fourth embodiment, showing the tire 1D in the same manner as in Figure 3 of the first embodiment. Figure 10 is a partially unfolded view of the joint between the support structure 10A and the support structure 10B of the fourth embodiment, unfolded in the tire circumferential direction C. In Figure 10, the inner joint 21 is mainly shown, but the outer joint 31, which has a similar configuration, is also shown with the corresponding reference numeral in parentheses. The tire 1D of the fourth embodiment is the same as the first embodiment, except that the inner joint 21 and the outer joint 31 have a nested structure. Therefore, parts that perform the same function as those of the first embodiment described above are given the same reference numerals, and redundant explanations are omitted as appropriate.

[0062] The inner joint portion 21 of the fourth embodiment has a two-stage configuration comprising a first joint line 21-1 and a second joint line 21-2. The first joint line 21-1 extends radially outward of the inner annular portion 20 in a wave-like shape with a curve along the tire circumferential direction C. The second joint line 21-2 extends radially inward of the inner annular portion 20 in a wave-like shape with a curve along the tire circumferential direction C.

[0063] The support structure 10A has a convex portion 22A-1 and a concave portion 23A-1 at the first joint line 21-1. The convex portion 22A-1 protrudes to one side in the tire axial direction (right side in the tire axial direction diagram in Figure 10). The concave portion 23A-1 is recessed to the other side in the tire axial direction (left side in the tire axial direction diagram in Figure 10).

[0064] The other support structure 10B also has a convex portion 22B-1 and a concave portion 23B-1 at the first joint line 21-1, similar to the support structure 10A. The convex portion 22B-1 protrudes to the other side in the tire axial direction (left side in the tire axial direction in Figure 10). The concave portion 23B-1 is recessed to one side in the tire axial direction (right side in the tire axial direction in Figure 10).

[0065] The shape of the convex portion 22A-1 of the support structure 10A matches the shape of the concave portion 23B-1 of the support structure 10B. Similarly, the shape of the concave portion 23A-1 of the support structure 10A matches the shape of the convex portion 22B-1 of the support structure 10B. The convex portions 22A-1, 22B-1 and the concave portions 23A-1, 23B-1 are arranged alternately and periodically in the tire circumferential direction C. In the tire 1 of this embodiment, the shape of the first joint line 21-1 when unfolded in the tire circumferential direction C is a wave-like shape with a curve.

[0066] The support structure 10A has a convex portion 22A-2 and a concave portion 23A-2 at the second joint line 21-2. The convex portion 22A-2 protrudes to one side in the tire axial direction (right side in the tire axial direction diagram in Figure 10). The concave portion 23A-2 is recessed to the other side in the tire axial direction (left side in the tire axial direction diagram in Figure 10).

[0067] The other support structure 10B also has a convex portion 22B-2 and a concave portion 23B-2 at the second joint line 21-2, similar to the support structure 10A. The convex portion 22B-2 protrudes to the other side in the tire axial direction (left side in the tire axial direction in Figure 10). The concave portion 23B-2 is recessed to one side in the tire axial direction (right side in the tire axial direction in Figure 10).

[0068] The shape of the protrusion 22A-2 of the support structure 10A matches the shape of the recess 23B-2 of the support structure 10B. Similarly, the shape of the recess 23A-2 of the support structure 10A matches the shape of the protrusion 22B-2 of the support structure 10B. The protrusions 22A-2, 22B-2 and the recesses 23A-2, 23B-2 are arranged alternately and periodically in the tire circumferential direction C. In the tire 1 of this embodiment, the shape of the second joint line 21-2 when unfolded in the tire circumferential direction C is a wave-like shape with a curve.

[0069] Furthermore, in this embodiment, the first joining line 21-1 and the second joining line 21-2 have similar shapes when viewed from the tire radial direction, and are positioned in a staggered positional relationship in the tire axial direction Y. That is, in Figures 9 and 10, the first joining line 21-1 is positioned parallel to the right in the tire axial direction Y compared to the second joining line 21-2. Also, in this embodiment, the positions where the convex portions 22A-1 and 22A-2 are located, and the positions where the concave portions 23A-1 and 23A-2 are located, are the same circumferential positions in the tire circumferential direction C of the support structure 10A. That is, the first joining line 21-1 and the second joining line 21-2 are arranged in a synchronous period in which the convex portions and concave portions are arranged in the tire circumferential direction C. The same applies to the support structure 10B. In other words, when viewed from the radial direction of the tire, the protrusions of the first joint line 21-1 and the second joint line 21-2, as well as the recesses of the first joint line 21-1 and the second joint line 21-2, are positioned at the same circumferential location.

[0070] The outer joint 31 is the same as the inner joint 21. That is, the outer joint 31 has a two-stage configuration with a first joint line 31-1 and a second joint line 31-2. The support structure 10A has a protrusion 32A-1 and a recess 33A-1 in the first joint line 31-1, and a protrusion 32A-2 and a recess 33A-2 in the second joint line 31-2. The support structure 10B has a protrusion 32B-1 and a recess 33B-1 in the first joint line 31-1, and a protrusion 32B-2 and a recess 33B-2 in the second joint line 31-2. Since these configurations are the same as the inner joint 21, a detailed explanation will be omitted.

[0071] As described above, by configuring the first joining line 21-1 and the second joining line 21-2, the tire 1D of this embodiment has a nested structure in the tire axial cross-section in which one support structure is partially concave and the other support structure has a convex shape corresponding to the concave shape. Therefore, the joining area between support structure 10A and support structure 10B can be increased. In addition, the position of support structure 10A and support structure 10B in the tire radial direction can also be restricted. Therefore, the tire 1D of the fourth embodiment can further improve reliability.

[0072] (Variation of the fourth embodiment) Figure 11 is a partially unfolded view of the joint between support structure 10A and support structure 10B in the tire circumferential direction C of the modified form of the fourth embodiment. The modified form of the fourth embodiment is the same as the fourth embodiment except that the relative positional relationship between the first joint line 21-1 and the second joint line 21-2 is different. In the modified form shown in Figure 11, the first joint line 21-1 and the second joint line 21-2 have similar shapes when viewed from the tire radial direction, and their positions in the tire axial direction Y are not shifted, and they are arranged in approximately the same positional relationship in the tire axial direction Y. On the other hand, in the modified form shown in Figure 11, the positions of the first joint line 21-1 and the second joint line 21-2 are shifted in the tire circumferential direction C. That is, in the modified form shown in Figure 11, the period in which the convex and concave portions of the first joint line 21-1 and the second joint line 21-2 are arranged in the tire circumferential direction C is shifted by half a period (half a pitch). Furthermore, the first bonding line 21-1 and the second bonding line 21-2 may have their convex and concave portions offset in the tire circumferential direction C regardless of the arrangement period. Even with this modified configuration of the fourth embodiment, reliability can be further improved, similar to the tire 1D of the fourth embodiment.

[0073] The tire 1 according to the embodiment described above provides the following effects.

[0074] (1) The tire 1 according to this embodiment comprises a tread 50 and a support structure 10, wherein a plurality of the support structures 10 (10A, 10B) are joined together in the tire axial direction, and each of the support structures 10 is annular and comprises an inner annular portion 20, an outer annular portion 30 arranged coaxially with the inner annular portion 20 on the outer circumference of the inner annular portion 20, and a connecting body 40 that connects the inner annular portion 20 and the outer annular portion 30, wherein the connecting body 40, in a cross-sectional view in the tire axial direction, has a first wall portion 41 that extends to one side in the tire axial direction as it moves from the outer annular portion 30 toward the inner annular portion 20, and The non-pneumatic tire, in which a plurality of support structures 10 are joined in the tire axial direction, has a second wall portion 42 extending to one side and a connecting portion 43 connecting the first wall portion 41 and the second wall portion 42, and has an inner joint portion 21 to which the inner annular portion 20 is joined and an outer joint portion 31 to which the outer annular portion 30 is joined, and at least one of the inner joint portion 21 and the outer joint portion 31 has convex portions 22A, 22B that protrude to one side in the tire axial direction when viewed from the outer diameter side or inner diameter side of the tire, and concave portions 23A, 23B that are recessed to the other side in the tire axial direction, and the convex portions 22A, 22B and the concave portions 23A, 23B are arranged alternately in the tire circumferential direction.

[0075] This increases the joint strength of the support structure 10, and makes it possible to provide a highly reliable non-pneumatic tire equipped with multiple support structures.

[0076] (2) A non-pneumatic tire as described in (1), wherein the convex portions 22A, 22B and the concave portions 23A, 23B are periodically arranged in the circumferential direction of the tire.

[0077] This makes it possible to increase the bonding strength uniformly in the circumferential direction of the tire.

[0078] (3) A non-pneumatic tire as described in (1) or (2), wherein the period in which the convex portions 22A, 22B and the concave portions 23A, 23B are arranged is 1.3% or more and 25% or less in ratio to the total circumference at the positions in which the convex portions 22A, 22B and the concave portions 23A, 23B are arranged.

[0079] This restricts the relative positions of support structure 10A and support structure 10B, thereby suppressing misalignment of the relative positions of support structure 10A and support structure 10B, as well as abnormal noise and damage due to friction and wear during rolling.

[0080] (4) A non-pneumatic tire as described in any of (1) to (3), wherein the height difference between the convex portions 22A, 22B and the concave portions 23A, 23B in the tire axial direction is 30% or more and 80% or less in ratio to the total width in the tire axial direction.

[0081] This restricts the relative positions of support structure 10A and support structure 10B, and more effectively suppresses misalignment of the relative positions of support structure 10A and support structure 10B, as well as abnormal noise and damage due to friction and wear during rolling.

[0082] (5) A non-pneumatic tire according to any of (1) to (4), wherein the non-pneumatic tire has a groove extending in the circumferential direction of the tire, which is arranged to overlap the convex portions 22A, 22B and the concave portions 23A, 23B, and is filled with adhesive.

[0083] This further increases the joint strength of the support structure 10.

[0084] (6) A non-pneumatic tire according to any of (1) to (5), wherein the shape of the inner joint 21 or the outer joint 31 when unfolded in the circumferential direction of the tire is a curved, wave-like shape.

[0085] This makes it possible to alleviate stress concentration at the inner joint 21 or the outer joint 31.

[0086] (7) A non-pneumatic tire as described in any of (1) to (5), wherein the shape of the inner joint 21 or the outer joint 31 when unfolded in the circumferential direction of the tire is a rectangular wave shape composed of straight line segments.

[0087] This restricts the relative positions of support structure 10A and support structure 10B, thereby suppressing misalignment of the relative positions of support structure 10A and support structure 10B, as well as abnormal noise and damage due to friction and wear during rolling.

[0088] (8) A non-pneumatic tire according to any one of (1) to (7), wherein at least one of the inner joint portion 21 and the outer joint portion 31 has a nested structure in which, in the tire axial cross section, one of the support structures 10 is partially concave and the other of the support structures 10 is convex corresponding to the concave shape.

[0089] This further increases the joint strength of the support structure 10.

[0090] (Transformed form) The embodiments described above are not limited to those described above, and various modifications and changes are possible, which are also within the scope of this disclosure.

[0091] (Modified Form 1) In each embodiment, examples of the shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire were described as a wave-shaped shape with curves and a rectangular wave-shaped shape composed of straight line segments. However, the shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire can be changed as appropriate. Figures 12 and 13 show modified forms of the shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire.

[0092] In the example shown in Figure 12, when the inner joint 21 or outer joint 31 is viewed by unfolding it in the circumferential direction of the tire, the shape is a zigzag pattern formed by intersecting straight line segments. In other words, it is a shape in which triangular shapes, excluding the base, are arranged in a row.

[0093] In the example shown in Figure 13, the shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire is the same as the shape in Figure 12, but with a straight line segment parallel to the circumferential direction of the tire added to the vertex. In other words, it is a shape consisting of a series of trapezoidal shapes, excluding the base.

[0094] As illustrated in Figures 12 and 13, the shape of the inner joint 21 or outer joint 31 when unfolded in the circumferential direction of the tire can be modified as appropriate.

[0095] (Modified form 2) In each embodiment, the inner edge 431 was described with an example in which it includes a connecting recess 433 that is recessed from the inner edge 431 side toward the outer edge 432 side in a cross-sectional view in the tire axial direction. However, it is not limited to this, and for example, it may be a configuration in which the first wall portion 41 and the second wall portion 42 extend as they are and are connected by a connecting portion 43, without including a shape corresponding to the connecting recess 433.

[0096] While each embodiment and its variations can be used in combination as appropriate, a detailed explanation is omitted. Furthermore, this disclosure is not limited to the embodiments described above. [Explanation of symbols]

[0097] 1, 1B, 1C, 1D Non-pneumatic tires 10(10A, 10B) Support structure 20 Inner annular portion 21 Inner joint 21-1 First Joining Line 21-2 Second Joining Line 22A Convex part 22B protrusion 23A Recess 23B Recess 25 Glue groove 30 Outer annular part 31 Outer joint 31-1 First Joining Line 31-2 Second Joining Line 32A Convex part 32B protrusion 33A Recess 33B Recess 35 Adhesive groove 40 Concatenation 41 1st wall 42 Second wall 43 Connecting part 50 tread 51 Tread 60 Adhesives 431 Common-law marriage 432 Outer edge 433 Connecting recess 433a Range of curved shape 433b Range of U-shape 434 Range of curved shapes

Claims

1. A non-pneumatic tire comprising a tread and a support structure, wherein a plurality of the support structures are joined together in a row in the tire axial direction, Each of the aforementioned support structures is annular, The inner annular part, An outer annular portion is arranged coaxially with the inner annular portion on the outer circumference side of the inner annular portion, A connecting body that connects the inner annular portion and the outer annular portion, Equipped with, In a cross-sectional view of the tire axial direction, the aforementioned connecting body A first wall portion extends to one side in the tire axial direction as it moves from the outer annular portion toward the inner annular portion, A second wall portion extends to one side as it moves from the inner annular portion toward the outer annular portion, A connecting portion that connects the first wall portion and the second wall portion, It has, The non-pneumatic tire, in which multiple support structures are joined together in the tire axial direction, The inner joint portion to which the inner annular portion is joined, The outer joint portion to which the outer annular portion is joined, It has, At least one of the inner joint and the outer joint is, when viewed from the outer diameter side of the tire or the inner diameter side of the tire, A protrusion that protrudes on one side in the axial direction of the tire, It has a recess that is recessed on the other side in the direction of the tire axis, A non-pneumatic tire in which the convex portions and concave portions are arranged alternately in the circumferential direction of the tire.

2. In the non-pneumatic tire according to claim 1, A non-pneumatic tire in which the convex portion and the concave portion are periodically arranged in the circumferential direction of the tire.

3. In the non-pneumatic tire described in claim 2, A non-pneumatic tire in which the period during which the convex portion and the concave portion are arranged is 1.3% or more and 25% or less in ratio to the total circumference length at the position in which the convex portion and the concave portion are arranged.

4. In the non-pneumatic tire according to claim 2 or claim 3, A non-pneumatic tire in which the height difference between the convex portion and the concave portion in the tire axial direction is 30% or more and 80% or less as a ratio to the total width in the tire axial direction.

5. In the non-pneumatic tire according to claim 1 or claim 2, A non-pneumatic tire having a groove extending in the circumferential direction of the tire, which is arranged to overlap the convex portion and the concave portion, and which is filled with adhesive.

6. In the non-pneumatic tire according to claim 1 or claim 2, A non-pneumatic tire in which, when unfolded in the circumferential direction of the tire, the shape of the inner joint or the outer joint is a curved, wave-like shape.

7. In the non-pneumatic tire according to claim 1 or claim 2, A non-pneumatic tire in which the shape of the inner joint or outer joint when unfolded in the circumferential direction of the tire is a rectangular wave shape composed of straight line segments.

8. In the non-pneumatic tire according to claim 1 or claim 2, A non-pneumatic tire in which at least one of the inner joint and the outer joint has a nested structure in which, in a tire axial cross section, one of the support structures is partially concave and the other support structure is convex corresponding to the concave shape.

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