Method and device for manufacturing airless tire

Abstract

To provide a method and device for manufacturing an airless tire that suppresses excessive deformation of a spoke.SOLUTION: A first force in a circumferential direction of a wheel is applied to a spoke so that a first distance D1 between a center C1 of the wheel 11 and the other end E1 of the spoke 13, one end of which is joined to the wheel, is less than a radius B of a first inner circumferential surface 124 of a tread 12, and the tread and the wheel with the first force applied to the spoke are arranged so that the first inner circumferential surface faces the other end, thereby removing the first force. Second force in the circumferential direction is applied to a first part of the spoke such that a second distance between a center of an inner ring and the other end of the spoke having one end joined to the inner ring is less than a radius of the first inner surface of the tread, a third force in an opposite direction to the second force is applied to a second part closer to the other end than the first part, the tread and the inner ring with the second and third forces applied to the spokes are arranged so that the other ends of the spokes face the first inner surface of the tread, thereby removing the second and third forces.SELECTED DRAWING: Figure 6B

Description

[Technical field]

[0001] The present invention relates to a manufacturing method and an apparatus for manufacturing an airless tire (also called a non-pneumatic tire or a non-pneumatic tire). [Background technology]

[0002] A method for manufacturing airless tires is known that uses a mold configured to receive a hub and a bottom piece of a tread, and fills cavities that define the spokes with polyurethane to form spokes extending from the hub to the tread (Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2014-507311 Summary of the Invention [Problem to be solved by the invention]

[0004] In airless tires, reinforcing materials (e.g., metal wires) may be provided in the tread along the circumferential direction of the airless tire to suppress excessive deformation of the spokes. In this case, a force is applied to the reinforcing material from the inner side to the outer side of the airless tire, generating tensile stress in the circumferential direction and increasing the rigidity of the reinforcing material.

[0005] However, airless tires manufactured using the above-mentioned conventional technology have the problem that the force from the hub to the tread is weakened due to shrinkage of the filled material, making it difficult to increase the rigidity of the reinforcing material and preventing excessive deformation of the spokes.

[0006] An object of the present invention is to provide a manufacturing method and manufacturing apparatus capable of manufacturing an airless tire that suppresses excessive deformation of the spokes. [Means for solving the problem]

[0007] The present invention solves the above problem by applying a first force in the circumferential direction of the wheel to multiple spokes so that a first distance between the center of the wheel and the other end of a spoke whose other end is joined to the wheel is less than the radius of a first inner circumferential surface of the tread, positioning the tread and the wheel with the first force applied to the multiple spokes so that the first inner circumferential surface faces the other ends, and removing the first force applied to the multiple spokes.

[0008] The present invention also solves the above problem by applying a second force in the circumferential direction of the inner ring to a first portion of the spokes, and applying a third force in the opposite direction to the second force to a second portion that is closer to the other end than the first portion, so that a second distance between the center of the inner ring and the other end of a spoke having one end joined to the inner ring is less than the radius of the first inner surface of the tread, positioning the tread and the inner ring with the second and third forces applied to the multiple spokes so that the other ends of the spokes face the first inner surface of the tread, and removing the second and third forces applied to the multiple spokes. Effect of the Invention

[0009] According to the present invention, it is possible to manufacture an airless tire in which excessive deformation of the spokes is suppressed. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is a front view illustrating an example of an airless tire according to an embodiment of the present invention. [Diagram 2] FIG. 2 is a perspective view showing an example of the wheel shown in FIG. [Diagram 3] FIG. 2 is a front view illustrating another example of an airless tire according to an embodiment of the present invention. [Figure 4] 4 is a cross-sectional view of a main portion showing an outer ring and a tread taken along the line AA in FIG. 3. [Diagram 5] FIG. 1 is a perspective view showing an example of an airless tire manufacturing apparatus according to an embodiment of the present invention. [Figure 6A]FIG. 6 is a plan view (part 1) showing the procedure for handling the wheels and treads in the manufacturing apparatus shown in FIG. 5. [Figure 6B] FIG. 6 is a plan view (part 2) showing the procedure for handling the wheels and treads in the manufacturing apparatus shown in FIG. 5. [Figure 6C] FIG. 6 is a plan view (part 3) showing the procedure for handling the wheels and treads in the manufacturing apparatus shown in FIG. 5. [Figure 7] FIG. 2 is a perspective view showing another example of an airless tire manufacturing apparatus according to an embodiment of the present invention. [Figure 8A] 8 is a plan view (part 1) showing a procedure for handling the wheel, the tread, and the inner ring in the manufacturing apparatus shown in FIG. 7. [Figure 8B] 8 is a plan view (part 2) showing the procedure for handling the wheel, the tread, and the inner ring in the manufacturing apparatus shown in FIG. 7. [Figure 8C] FIG. 8 is a plan view (part 3) showing the procedure for handling the wheel, the tread, and the inner ring in the manufacturing apparatus shown in FIG. 7. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. For convenience of description, the side (outside) of a vehicle when an airless tire is mounted on the vehicle is defined as the front side. In the drawings, "front", "rear", "upper", "lower", "right" and "left" respectively indicate the front, rear, upper, lower, right and left of a vehicle on which an airless tire is mounted, the X-axis and the Y-axis respectively indicate the horizontal and vertical directions when an airless tire manufacturing device (hereinafter also simply referred to as a manufacturing device) is viewed in a plane, and the Z-axis indicates the height direction relative to the installation position of the manufacturing device. In the following description, the radial direction of an airless tire is simply referred to as the radial direction, and the circumferential direction of an airless tire is simply referred to as the circumferential direction. The radial direction of an airless tire is the same direction as the radial direction of a wheel and an inner ring, and the circumferential direction of an airless tire is the same direction as the circumferential direction of a wheel and an inner ring.

[0012] [Airless tire configuration] Fig. 1 is a front view showing an example of an airless tire according to an embodiment of the present invention. An airless tire is a tire that supports a vehicle body not by air pressure but by the reaction force of spokes made of an elastic material (hereinafter also referred to as an elastic material). The airless tire of this embodiment can be applied to four-wheeled automobiles, two-wheeled automobiles, industrial vehicles, bicycles, and other vehicles, as well as carts. As shown in Fig. 1, the airless tire 1 of this embodiment includes a wheel 11, a tread 12, spokes 13, and an intermediate ring 14.

[0013] The wheel 11 is a member that is fixed to a hub (not shown) of the vehicle to connect with the vehicle, and is made of metal or other highly rigid materials. As shown in FIG. 2, the wheel 11 is made up of a disk-shaped disc 111 and a cylindrical rim 112. The disc 111 is shown in FIG. 1 as a circular member in the center of the airless tire 1, and the airless tire 1 is supported on the axle by fixing the disc 111 to the hub of the vehicle. The shape of the wheel 11 can be appropriately set according to the required specifications of the airless tire 1. The disc 111 and the rim 112 may be molded as a single unit, or may be combined after being molded separately.

[0014] The tread 12 is a cylindrical member having a tire width, and is disposed on the outermost periphery of the airless tire 1 to come into contact with the road surface. The tread 12 is made of a composite material in which an elastic material such as natural rubber or synthetic rubber is reinforced with a metal or resin tire cord. A tread pattern is formed on the outer periphery of the tread 12, as in conventional pneumatic tires, and forms the contact surface with the road surface. The inner diameter, outer diameter, thickness, and shape of the tread pattern of the tread 12 can be appropriately set according to the required specifications of the airless tire 1.

[0015] The spokes 13 are members that support a load (e.g., the vehicle weight) applied to the airless tire 1, and are plate-like members made of an elastic material such as an elastic thermoplastic resin or an elastic thermosetting resin, and have a width corresponding to the tire width. The spokes 13 extend radially from the outer periphery side of the wheel 11 (specifically, the outer periphery side of the rim 112) toward the inner periphery side of the tread 12, and are provided in plurality at equal intervals and spaced apart from each other along the circumferential direction of the airless tire 1. The spokes 13 are provided axially symmetrically with respect to the central axis of the airless tire 1. There is no particular limit to the number of spokes 13 provided on one airless tire 1, and the number can be set appropriately depending on the ground contact length of the airless tire 1, the load bearing value of the spokes 13, vibration resistance, and other required specifications of the airless tire 1.

[0016] The means for attaching the spokes 13 to the wheel 11 is not particularly limited as long as robustness can be ensured. For example, a groove may be formed in the outer peripheral surface (hereinafter also referred to as the first outer peripheral surface) of the rim 112 constituting the wheel 11, and the inner peripheral end portion (hereinafter also referred to as the one end) of the spokes 13 may be fitted into this groove. The first outer peripheral surface and the one end may be bonded with an adhesive, or may be connected with a bolt. Similarly, the means for attaching the spokes 13 to the tread 12 is not particularly limited as long as robustness can be ensured. For example, the inner peripheral surface (hereinafter also referred to as the first inner peripheral surface) of the tread 12 and the outer peripheral end portion (hereinafter also referred to as the other end) of the spokes 13 may be bonded with an adhesive, or may be connected with a bolt.

[0017] The intermediate ring 14 is a member that transmits the deformation of the spokes 13 in the circumferential direction to the adjacent spokes 13 in order to support the load by the entire airless tire 1 when the spokes 13 are deformed by a radial load. The intermediate ring 14 is made of an elastic material such as an elastic thermoplastic resin or an elastic thermosetting resin, like the spokes 13. The intermediate ring 14 has a cylindrical shape concentric with the wheel 11 and the tread 12, and is provided between the wheel 11 and the tread 12 to connect the multiple spokes 13 to each other. The means for attaching the intermediate ring 14 to the spokes 13 is not particularly limited as long as robustness can be ensured. For example, the intermediate ring 14 is bonded to the spokes 13 by an adhesive. Alternatively, the spokes 13 and the intermediate ring 14 may be integrally molded. The airless tire 1 shown in FIG. 1 has three intermediate rings 14a, 14b, and 14c, but the number of intermediate rings 14 provided in one airless tire 1 is not particularly limited.

[0018] Fig. 3 is a front view showing another example of an airless tire according to an embodiment of the present invention. The airless tire 1a shown in Fig. 3 includes an inner ring 15 and an outer ring 16 in addition to a wheel 11, a tread 12, spokes 13, and an intermediate ring 14.

[0019] The inner ring 15 is an annular member that connects one ends of the multiple spokes 13, and is made of, for example, the same material as the spokes 13. The inner side of the inner ring 15 is joined to the outer side of the wheel 11. For example, protrusions are provided on the inner surface of the inner ring 15 (hereinafter also referred to as the third inner surface) and the protrusions are fitted into grooves formed in the first outer surface for joining. Alternatively, the third inner surface and the first outer surface may be bonded with an adhesive. In addition, the outer side of the inner ring 15 is joined to the spokes 13. For example, one end of the spokes 13 is joined to the outer surface of the inner ring 15 (hereinafter also referred to as the third outer surface) with an adhesive. The inner ring 15 may be integrally molded with the spokes 13.

[0020] The outer circumferential ring 16 is an annular member that connects the other ends of the multiple spokes 13, and is made of, for example, the same material as the spokes 13. The outer circumferential side of the outer circumferential ring 16 is bonded to the inner circumferential side of the tread 12. For example, an adhesive is used to bond the outer circumferential surface (hereinafter also referred to as the second outer circumferential surface) of the outer circumferential ring 16 to the first inner circumferential surface. The inner circumferential side of the outer circumferential ring 16 is bonded to the spokes 13. For example, an adhesive is used to bond the other ends of the spokes 13 to the inner circumferential surface (hereinafter also referred to as the fourth inner circumferential surface) of the outer circumferential ring 16. The outer circumferential ring 16 may be molded integrally with the spokes 13. The spokes 13, the inner circumferential ring 15, and the outer circumferential ring 16 may be molded integrally, or the spokes 13, the intermediate ring 14, the inner circumferential ring 15, and the outer circumferential ring 16 may be molded integrally.

[0021] By providing the inner ring 15, the bonding area with the rim 112 is increased compared to when the spokes 13 are directly bonded to the wheel 11, improving the load-bearing capacity of the airless tire 1a. Similarly, by providing the outer ring 16, the bonding area with the tread 12 is increased compared to when the spokes 13 are directly bonded to the tread 12, improving the load-bearing capacity of the airless tire 1a. The inner ring 15 and the outer ring 16 have a width equivalent to the tire width (for example, a width within a range of the tire width ±5%) and an appropriate thickness according to the required specifications of the airless tire 1a.

[0022] When the airless tire includes an inner ring 15, the spokes 13 extend radially from the third outer peripheral surface toward the first inner peripheral surface, connecting the inner ring 15 and the tread 12. When the airless tire includes an outer peripheral ring 16, the spokes 13 extend radially from the first outer peripheral surface toward the fourth inner peripheral surface, connecting the wheel 11 and the outer peripheral ring 16. When the airless tire includes an inner ring 15 and an outer peripheral ring 16 like the airless tire 1a shown in Fig. 3, the spokes 13 extend radially from the third outer peripheral surface toward the fourth inner peripheral surface, connecting the inner ring 15 and the outer peripheral ring 16.

[0023] Fig. 4 is a cross-sectional view of a main part showing the outer circumferential ring 16 and the tread 12 in the AA section of Fig. 3, which is a section perpendicular to the circumferential direction of the airless tire 1a. The tread 12 shown in Fig. 4 is in contact with the road surface and has a first elastic portion 121 made of an elastic material and a first reinforcing layer 122 extending in the width direction of the tread 12 (the left-right direction of the vehicle). The first reinforcing layer 122 includes tire cords 122a and hard rubber, and has a higher rigidity than the first elastic portion 121 made of an elastic material. In order to make it easier to generate tensile stress in the circumferential direction in the tire cords 122a, the first reinforcing layer 122 is disposed at a position closer to the first inner circumferential surface 124 than the contact surface 123 that comes into contact with the road surface.

[0024] On the other hand, the outer circumferential ring 16 shown in Fig. 4 has a second elastic portion 161 made of an elastic material, and a second reinforcing layer 162 extending in the width direction (left-right direction of the vehicle) of the outer circumferential ring 16. The second reinforcing layer 162 includes tire cords 162a and hard rubber, and has higher rigidity than the second elastic portion 161. Like the airless tire 1a shown in Fig. 4, the tread 12 of the airless tire 1 shown in Fig. 1 also has a first elastic portion 121 and a first reinforcing layer 122.

[0025] The intermediate ring 14, the inner ring 15, and the outer ring 16 are not essential components of the airless tire according to the embodiment of the present invention, and may be provided as necessary or may be omitted.

[0026] [Manufacturing method of airless tires] In the manufacturing method of an airless tire according to the embodiment of the present invention, a wheel 11 and a tread 12 are prepared, and an airless tire is manufactured by combining the wheel 11 and the tread 12. The wheel 11 includes a plurality of spokes 13 that extend radially from a first outer circumferential surface to which one end is joined, and that are deformable in the radial direction, with the distance between the center of the wheel 11 and the other end being a predetermined distance longer than the radius of the first inner circumferential surface 124. When combining the wheel 11 and the tread 12, the plurality of spokes 13 are deformed in the circumferential direction and / or the radial direction so that the distance between the center of the wheel 11 and the other end is less than the radius of the first inner circumferential surface 124, and the tread 12 and the plurality of spokes 13 in the deformed state are arranged so that the first inner circumferential surface and the other end face each other, and the plurality of spokes 13 in the deformed state are returned to their pre-deformed state. Two embodiments of the manufacturing method of an airless tire are described below. First Embodiment

[0027] Fig. 5 is a perspective view showing an example of a manufacturing apparatus according to an embodiment of the present invention. The manufacturing apparatus 2 shown in Fig. 5 is an apparatus for manufacturing an airless tire in which the spokes 13 are directly joined to the wheel 11 without having an inner circumferential ring 15, like the airless tire 1 shown in Fig. 1. As shown in Fig. 5, the manufacturing apparatus 2 includes a first base 21, a fixed member 22, a first rotating member 23, a first pin 24, and transport mechanisms 25 and 26.

[0028] The first pedestal 21 is a member that supports the devices that constitute the manufacturing apparatus 2. The first pedestal 21 is installed, for example, on a level ground and its position is fixed by anchor bolts or the like. The first pedestal 21 has an appropriate shape and rigidity within a range that allows it to appropriately support the devices that constitute the manufacturing apparatus 2.

[0029] The fixing member 22 is a member that fixes the wheel 11 to the first pedestal 21, and is not particularly limited as long as it can fix the wheel 11 to the first pedestal 21. As an example, the fixing member 22 shown in Fig. 5 has a pedestal portion that is provided in the center of the first pedestal 21 and fixed to the first pedestal 21 (or is part of the first pedestal 21), and a pin that is inserted into a hole provided in the disc 111. The hole in the disc 111 is a hole through which a bolt is inserted when connecting the wheel 11 to the vehicle. When the wheel 11 is fixed by the fixing member 22 shown in Fig. 5, the Z-axis direction is the width direction of the wheel 11.

[0030] The first rotating member 23 is a member attached to the first base 21, and is rotatable in the circumferential direction of the wheel 11 fixed to the fixed member 22. For example, the first rotating member 23 shown in Fig. 5 rotates in the circumferential direction on an XY plane perpendicular to the Z axis. The first rotating member 23 is supported, for example, by a guide rail (not shown) curved along the circumferential direction, and has a shaft (not shown) extending in the Z axis direction, and the first rotating member 23 is rotated by rotating this shaft by a motor or the like.

[0031] The first pin 24 is a pin fixed to the first rotating member 23 along the circumferential direction, and as shown in FIG. 5, a plurality of first pins 24 are fixed to the first rotating member 23. One end of the first pin 24 is fixed to the first rotating member 23, and extends in the Z-axis direction (width direction of the wheel 11). The method of fixing the first pin 24 to the first rotating member 23 is not particularly limited, and the first pin 24 may be fixed by a bolt or adhesive, or the first rotating member 23 and the first pin 24 may be integrally molded. Since the first pin 24 is a pin that applies a first force in the circumferential direction to the spokes 13, it has an appropriate shape and rigidity within a range in which the spokes 13 made of an elastic material can be deformed. In addition, the arrangement of the first pin 24 can be appropriately set within a range in which the spokes 13 can be appropriately deformed, and the shape of the first rotating member 23 depends on the arrangement of the first pin 24. The first force will be described later.

[0032] The transport mechanism 25 is a mechanism for transporting the tread 12, and is not particularly limited as long as it can appropriately place the tread 12 in the manufacturing apparatus 2. As an example, the transport mechanism 25 shown in FIG. 5 is a cylindrical member, and a support part 25a for supporting the tread 12 is provided at the lower end of the inner periphery side of the transport mechanism 25. The transport mechanism 25 is moved in the X-axis direction, the Y-axis direction, and the Z-axis direction by an arm (not shown) or the like provided above the manufacturing apparatus 2. On the other hand, the transport mechanism 26 is a mechanism for transporting the wheel 11 and the inner periphery ring 15, and takes out the manufactured airless tire 1 from the manufacturing apparatus 2. The transport mechanism 26 is, for example, a robot arm as shown in FIG. 5, but is not particularly limited as long as it can appropriately handle the wheel 11 and the like.

[0033] When the airless tire 1 shown in FIG. 1 is manufactured using the manufacturing apparatus 2 shown in FIG. 5, first, the wheel 11 including a plurality of spokes 13 extending radially from a first outer peripheral surface to which one end is joined and deformable in the circumferential direction of the wheel 11, and the tread 12 are prepared (step S1). The wheel 11 including the spokes 13 is manufactured by integrally molding the spokes 13 and the intermediate ring 14 made of an elastic material (e.g., urethane resin such as thermoplastic polyurethane) using a molding method such as injection molding or vacuum casting, and joining one end of the spokes 13 to the first outer peripheral surface of the disk 111. As described above, the method of joining the one end of the spokes 13 to the first outer peripheral surface is not particularly limited as long as robustness can be ensured. Alternatively, the wheel 11 may be inserted into a mold and integrally molded (insert molding) together with the spokes 13 and the intermediate ring 14. On the other hand, the tread 12 is manufactured, for example, by wrapping the tire cord 122a corresponding to the first reinforcing layer 122 with raw rubber corresponding to the first elastic portion 121 to form a prepreg, and then heating and pressurizing (vulcanizing) the prepreg.

[0034] The shapes of the spokes 13 and the intermediate ring 14 can be appropriately set within a range in which the spokes 13 can be deformed in the circumferential direction by the first pins 24. The diameter of the wheel 11 and the length of the spokes 13 are set so that a first distance from the center of the wheel 11 to the other ends of the multiple spokes 13 is longer than the radius of the first inner circumferential surface by a first predetermined distance. As an example, in the wheel 11 and spokes 13 shown in FIG. 6A, a first distance D1 from the center C1 of the wheel to the other ends E1 of the spokes 13 is set to be longer than the radius B of the first inner circumferential surface 124 shown in FIG. 6B by a first predetermined distance. The first predetermined distance can be set to an appropriate value within a range in which the other ends E1 of the spokes 13 can be pressed against the first inner circumferential surface 124 and the spokes 13 can be fixed to the tread 12, and is, for example, 5 to 10% of the radius B of the first inner circumferential surface 124.

[0035] Next, the wheel 11 having a plurality of spokes 13 is transported by a transport mechanism 26 shown by a dashed line in Fig. 6A, and the pins of the fixing member 22 are inserted into the holes of the disk 111 to fix the wheel 11 to the fixing member 22 (step S2). In the manufacturing apparatus 2, the first pins 24 are disposed between adjacent spokes 13, and therefore, when fixing the wheel 11 to the fixing member 22, the first pins 24 are inserted between adjacent spokes 13 as shown in Fig. 6A. Note that the number of first pins 24 does not necessarily need to be the same as the number of spokes 13, and for example, the first pins 24 may be disposed every other spoke 13 between adjacent spokes 13.

[0036] Next, a first force in the circumferential direction is applied to the multiple spokes 13 so that the first distance D1 shown in FIG. 6A is less than the radius B of the first inner peripheral surface 124 shown in FIG. 6B (step S3). As an example, in the manufacturing apparatus 2, the first rotating member 23 is rotated in the direction of the arrow A1 (counterclockwise), and a first force is applied to the multiple spokes 13 in contact with the first pin 24 so that the first distance D1 for all the spokes 13 is less than the radius B of the first inner peripheral surface 124. By applying the first force to the spokes 13 shown in FIG. 6A, the spokes 13 are deformed and the radial length is shortened (diameter is reduced), and as shown in FIG. 6B, the first distance D1 is shorter than the radius B of the first inner peripheral surface 124. Note that, in the manufacturing apparatus 2 shown in FIG. 5, a pin is used to apply the first force, but the means for applying the force to the spokes 13 is not limited to a pin. For example, the spokes 13 may be held by a clamp or the like, and the clamp holding the spokes 13 may be moved in the circumferential direction. Additionally, the radial length of each spoke 13 to which the first force is applied may vary.

[0037] Next, the tread 12 is transported using the transport mechanism 25 shown by the dashed line in Fig. 6B, and the tread 12 and the wheel 11 in a state in which the first force is applied to the multiple spokes 13 are arranged so that the first inner circumferential surface 124 and the other end E1 face each other (step S4). As an example, in the manufacturing device 2, as shown in Fig. 6B, the transport mechanism 25 in a state in which the tread 12 is supported by the support portion 25a is moved from above to below the manufacturing device 2 along the Z-axis direction, and the tread 12 is arranged outside the multiple spokes 13 in a state in which the first force is applied so that the first inner circumferential surface 124 and the other end E1 face each other. Before moving the transport mechanism 25 along the Z-axis direction, the transport mechanism 26 moves to a position that does not obstruct the movement of the transport mechanism 25.

[0038] Next, in a state where the wheel 11 and the tread 12 are arranged so that the first inner circumferential surface 124 and the other end E1 face each other, the first force applied to the spokes 13 is removed, and the other end E1 of the spokes 13 is pressed against the first inner circumferential surface 124 to be in close contact with each other, and the spokes 13 are fixed to the tread 12 (step S5). As an example, in the manufacturing apparatus 2, in a state where the tread 12 is arranged so that the first inner circumferential surface 124 and the other end E1 face each other, as shown in FIG. 6B, the first rotating member 23 is rotated in the reverse direction in the direction of the arrow A2, and the first force is removed from the spokes 13. In a state where the first force is removed from the spokes 13 as shown in FIG. 6C, the first distance D1 is longer than the radius B of the first inner circumferential surface 124, so that the other end E1 of the spokes 13 is pressed against the first inner circumferential surface 124 and fixed to the first inner circumferential surface 124. Furthermore, the other ends E1 of the spokes 13 are pressed against the first inner circumferential surface 124, so that tensile stress is generated in the tire cords 122a of the tread 12 in the circumferential direction.

[0039] The airless tire 1 manufactured by combining the wheel 11 and the tread 12 is removed from the manufacturing apparatus 2 by using the transport mechanism 26 (step S6). The removed airless tire 1 is transported to the next step. Then, the transport mechanism 26 transports a new wheel (step S7). Thereafter, steps S2 to S7 are repeated until the desired number of airless tires 1 have been manufactured. Furthermore, if the wheel 11 and the tread 12 are required, step S1 is executed as necessary.

[0040] In addition to the multiple spokes 13, the wheel 11 may include an outer circumferential ring 16 having a second outer circumferential surface with a second diameter that is longer than the first diameter of the first inner circumferential surface 124 by a first predetermined length. The first predetermined length can be set to an appropriate value within a range in which the second outer circumferential surface can be pressed against the first inner circumferential surface 124 and the outer circumferential ring 16 can be fixed to the tread 12, and is, for example, 2.5 to 5% of the first diameter of the first inner circumferential surface 124. The first predetermined length may also be simply referred to as a predetermined length.

[0041] When the wheel 11 includes an outer ring 16, the manufacturing device 2 applies a first force to the spokes 13 so that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter (step S3a). Then, the tread 12 and the wheel 11 with the first force applied to the spokes 13 are arranged so that the first inner peripheral surface 124 and the second outer peripheral surface face each other (step S4a), the first force applied to the spokes 13 is removed, and the second outer peripheral surface is pressed against the first inner peripheral surface 124 to be in close contact (step S5a). That is, when the wheel 11 includes an outer ring 16, in step S1, the wheel 11 including the spokes 13 and the outer ring 16 is prepared, and steps S3 to S5 are replaced with steps S3a to S5a. In step S3a, it is not necessary for the diameter of the second outer peripheral surface to be uniformly reduced, and it is sufficient that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter.

[0042] As an example, in the manufacturing apparatus 2, the wheel 11 having the spokes 13 and the outer ring 16 is fixed to the fixed member 22 by the conveying mechanism 26, the first rotating member 23 is rotated clockwise on the XY plane, and a first force is applied to the multiple spokes 13 in contact with the first pins 24 so that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter. Then, the conveying mechanism 25 with the tread 12 supported on the support portion 25a is moved from above to below the manufacturing apparatus 2 along the Z axis direction, and the tread 12 is arranged outside the multiple spokes 13 to which the first force is applied so that the first inner peripheral surface 124 and the second outer peripheral surface face each other, and the first rotating member 23 is rotated counterclockwise on the XY plane to remove the first force from the spokes 13.

[0043] When the contact surface 123 of the tread 12 is worn, the tread 12 of the airless tire 1 is replaced with another tread using the manufacturing device 2. For example, with the conveying mechanism 25 moved downward in the Z-axis direction as shown in FIG. 6B, the wheel 11 of the airless tire 1 is fixed to the fixed member 22 by the conveying mechanism 26. Next, the first rotating member 23 is rotated to apply a first force to the multiple spokes 13 fixed to the tread 12 so that the first distance D1 is less than the radius B of the first inner circumferential surface 124, thereby separating the multiple spokes 13 from the tread 12. The separated tread 12 is conveyed to the next process (e.g., a regeneration process) by the conveying mechanism 25.

[0044] Next, another tread different from the separated tread 12 is placed on the support part 25a of the conveying mechanism 25, and the conveying mechanism 25 is moved to place the other tread and the wheel 11 with the first force applied to the multiple spokes 13 so that the inner circumferential surface of the other tread (hereinafter also referred to as the second inner circumferential surface) faces the other end E1. Then, the first rotating member 23 is rotated in the reverse direction to remove the first force applied to the multiple spokes 13, and the multiple spokes 13 are fixed to the other tread. The airless tire 1 with the replaced tread 12 is taken out of the manufacturing apparatus 2 by the conveying mechanism 26. Note that when the wheel 11 has an outer circumferential ring 16, the tread 12 can be replaced in a similar manner. In this case, the wheel 11 and the other tread are placed so that the second inner circumferential surface and the second outer circumferential surface face each other.

[0045] 1, when the airless tire 1 includes an intermediate ring 14, the intermediate ring 14 transmits the circumferential deformation of the spokes 13 to the adjacent spokes 13, and therefore when applying the first force to the multiple spokes 13 to make the first distance D1 less than the radius B of the first inner circumferential surface 124, the first force may be applied to only some of the multiple spokes 13. For example, every other first pin 24 shown in FIG. 5 is thinned out so that every other first pin 24 is disposed between adjacent spokes 13, and the first force is applied to every other spoke 13. This makes it possible to prevent the spokes 13 from being narrowed more than necessary.

[0046] The spokes 13 may have multiple bent portions between one end and the other end that are bent in a direction connecting the one end and the other end. For example, the spokes 13 shown in FIG. 6A have bent portions 131, 132, and 133 between one end and the other end that deform in the circumferential direction. When the spokes 13 have the bent portions 131, 132, and 133, a first force is applied to the bent portions 131, 132, and 133 when a first force is applied to the multiple spokes 13 to make the first distance D1 less than the radius B of the first inner circumferential surface 124. For example, the first pin 24 shown in FIG. 6A applies a first force to the bent portion 133 when rotating in the direction of the arrow A1. This allows the spokes 13 to be reduced in diameter with a small first force.

[0047] The intermediate ring 14 may also connect the bent portions 131, 132, and 133 of the spokes 13 to each other. For example, the intermediate ring 14a shown in Fig. 6A connects the bent portion 131 to the bent portions 131a and 131b of the adjacent spokes 13. In this case, when a first force is applied to the multiple spokes 13 to make the first distance D1 less than the radius B of the first inner circumferential surface 124, the first force may be applied to only some of the multiple spokes 13. This allows the diameter of the spokes 13 to be reduced with a small first force.

[0048] Second Embodiment Fig. 7 is a perspective view showing another example of a manufacturing apparatus according to an embodiment of the present invention. The manufacturing apparatus 3 shown in Fig. 7 is an apparatus for manufacturing an airless tire having an inner circumferential ring 15 and having spokes 13 not directly joined to a wheel 11, like the airless tire 1a shown in Fig. 3. As shown in Fig. 7, the manufacturing apparatus 3 includes a second base 31, a second rotating member 32, a third rotating member 33, a second pin 34, a third pin 35, and transport mechanisms 36 and 37.

[0049] The second pedestal 31 is a member that supports the devices that constitute the manufacturing apparatus 3, and is fixed in position similarly to the first pedestal 21. The second pedestal 31 has an appropriate shape and rigidity within a range that allows it to appropriately support the devices that constitute the manufacturing apparatus 3.

[0050] The second rotating member 32 and the third rotating member 33 are members attached to the second pedestal 31 and are rotatable in the circumferential direction relative to the second pedestal 31. For example, the second rotating member 32 and the third rotating member 33 shown in FIG. 7 rotate in the circumferential direction on an XY plane perpendicular to the Z axis. The mechanism by which the second rotating member 32 and the third rotating member 33 rotate is similar to that of the first rotating member 23. Furthermore, as shown in FIG. 7, the third rotating member 33 is disposed outside the second rotating member 32.

[0051] The second pin 34 is a pin fixed to the second rotating member 32 along the circumferential direction, and as shown in FIG. 7, a plurality of second pins 34 are fixed to the second rotating member 32. One end of the second pin 34 is fixed to the second rotating member 32 and extends in the Z-axis direction. The method of fixing the second pin 34 is not particularly limited. The second rotating member 32 and the second pin 34 may be integrally molded. On the other hand, the third pin 35 is a pin fixed to the third rotating member 33 along the circumferential direction, and as shown in FIG. 7, a plurality of third pins 35 are fixed to the third rotating member 33. One end of the third pin 35 is fixed to the third rotating member 33 and extends in the Z-axis direction. The method of fixing the third pin 35 is not particularly limited. The third rotating member 33 and the third pin 35 may be integrally molded.

[0052] The second pin 34 and the third pin 35 are pins that apply the second and third forces in the circumferential direction to the spokes 13, respectively, and therefore have an appropriate shape and rigidity within a range in which the spokes 13 made of an elastic material can be deformed. The arrangement of the second pin 34 and the third pin 35 can be appropriately set within a range in which the spokes 13 can be appropriately deformed, and the radial distance between the second pin 34 and the third pin 35 can be appropriately set within a range in which the spokes 13 can be appropriately deformed. The shapes of the second rotating member 32 and the third rotating member 33 depend on the arrangement of the second pin 34 and the third pin 35, respectively. The second force and the third force will be described later.

[0053] The transport mechanism 36, like the transport mechanism 25, is a mechanism for transporting the tread 12, and has a support portion 36a that supports the tread 12. The transport mechanism 37, like the transport mechanism 26, is a mechanism for transporting the wheel 11 and the inner ring 15.

[0054] When manufacturing an airless tire in which one ends of the multiple spokes 13 shown in FIG. 1 are connected by an inner ring 15 using a manufacturing apparatus 3 shown in FIG. 7, first, a wheel 11, a tread 12, and an inner ring 15 having a third outer circumferential surface to which one ends of the multiple spokes 13 are connected are prepared (step S11). When the tread 12 and the inner ring 15 are joined using the manufacturing apparatus 3 and the wheel 11 and the inner ring 15 are joined separately, the tread 12 and the inner ring 15 having a third outer circumferential surface are prepared in step S11. The inner ring 15 includes multiple spokes 13 that extend radially from the third outer circumferential surface to which one ends are joined and are deformable in the circumferential direction of the inner ring 15. In addition, the diameter (inner diameter) of the inner ring 15 is set to be shorter than the diameter (outer diameter) of the wheel 11 by a second predetermined length. The second predetermined length can be set to an appropriate value within a range in which the third inner peripheral surface can be appropriately joined to the first outer peripheral surface, and is, for example, 1 to 5% of the diameter of the wheel 11. The inner peripheral ring 15 is integrally molded together with the spokes 13 and the intermediate ring 14 made of an elastic material, using a molding method such as injection molding or vacuum casting. The manufacturing method of the tread 12 is the same as that of the first embodiment, and therefore will not be described.

[0055] The shapes of the spokes 13 and the intermediate ring 14 can be appropriately set within a range in which the spokes 13 can be deformed in the circumferential direction by the second pin 34 and the third pin 35. In addition, the outer diameter of the inner ring 15 (i.e., the diameter of the third outer peripheral surface) and the length of the spokes 13 are set so that the second distance from the center of the inner ring 15 to the other ends of the multiple spokes 13 is longer than the radius B of the first inner peripheral surface 124 by a second predetermined distance. As an example, in the inner ring 15 shown in FIG. 8A, the second distance D2 from the center C2 of the inner ring 15 to the other ends E2 of the spokes 13 is set to be longer than the radius B of the first inner peripheral surface 124 by a second predetermined distance as shown in FIG. 8B. The second predetermined distance can be set to an appropriate value within a range in which the spokes 13 can be fixed to the tread 12, similar to the first predetermined distance, and is, for example, 5 to 10% of the radius B of the first inner peripheral surface 124.

[0056] Next, the inner ring 15 having the plurality of spokes 13 is transported by a transport mechanism 37 shown by a dashed line in Fig. 8A, and the second pins 34 and the third pins 35 are inserted between adjacent spokes 13 (step S12). In the state shown in Fig. 8A, the Z-axis direction is the width direction of the airless tire. The second pins 34 and the third pins 35 are arranged so as to be inserted between adjacent spokes 13 as shown in Fig. 8A. Note that the number of the second pins 34 and the third pins 35 does not necessarily need to be the same as the number of spokes 13, and for example, the second pins 34 and the third pins 35 may be arranged every other one between adjacent spokes 13.

[0057] Next, in order to make the second distance D2 shown in FIG. 8A less than the radius B of the first inner circumferential surface 124 shown in FIG. 8B, a second force is applied to the first portion of the spokes 13 in the circumferential direction, and a third force is applied to a second portion closer to the other end E2 than the first portion, in the opposite direction to the second force (step S13). As an example, in the manufacturing apparatus 3, the second rotating member 32 is rotated in the direction of the arrow A3 (first direction), and the second force is applied to the portion (first portion) of the spokes 13 that contacts the second pin 34 between the intermediate ring 14a and the intermediate ring 14b. At the same time, the third rotating member 33 is rotated in the direction of the arrow A4 (second direction), and the third force is applied to the portion (second portion) of the spokes 13 that contacts the third pin 35 outside the intermediate ring 14c. By applying the second and third forces to the spoke 13 shown in FIG. 8A, the spoke 13 deforms and its radial length shortens (reduced in diameter), and as shown in FIG. 8B, the second distance D2 becomes shorter than the radius B of the first inner surface 124.

[0058] In the manufacturing apparatus 3 shown in Fig. 7, pins are used to apply the second and third forces, but the means for applying forces to the spokes 13 is not limited to pins. For example, the spokes 13 may be held by a clamp or the like, and the clamp holding the spokes 13 may be moved in the circumferential direction. The radial length of the spokes 13 to which the second and third forces are applied may be different for each spoke 13. In step S13, the second pin 34 and the third pin 35 may move in opposite directions relative to each other, thereby applying the second and third forces to one spoke 13, and one of the second pin 34 and the third pin 35 may move in the circumferential direction and the other may be stationary.

[0059] Next, the tread 12 is transported using a transport mechanism 36 shown by a dashed line in FIG. 8B, and the tread 12 and the inner ring 15 in a state in which the second force and the third force are applied to the multiple spokes 13 are arranged so that the first inner circumferential surface 124 and the other end E2 face each other (step S14-1). Furthermore, the wheel 11 is transported using a transport mechanism 37 shown by a dashed line in FIG. 8B, and the wheel 11 and the inner ring 15 in a state in which the second force and the third force are applied to the multiple spokes 13 are arranged so that the first outer circumferential surface of the wheel 11 faces the third inner circumferential surface of the inner ring 15 (step S14-2). When the tread 12 and the inner ring 15 are joined using the manufacturing device 3 and the wheel 11 and the inner ring 15 are joined separately, step S14-2 is not performed and the wheel 11 is not arranged. 8B, in the manufacturing apparatus 3, the conveying mechanism 36 supporting the tread 12 on the support portion 36a is moved from above to below the manufacturing apparatus 3 along the Z-axis direction, and the tread 12 is disposed outside the spokes 13 such that the first inner circumferential surface 124 faces the other end E2. The wheel 11 is gripped by the conveying mechanism 37, and the wheel 11 is disposed inside the inner ring 15 such that the first outer circumferential surface faces the third inner circumferential surface. The manufacturing apparatus 3 may have a fixing member for fixing the wheel 11, as in the manufacturing apparatus 2, and the wheel 11 gripped by the conveying mechanism 37 may be fixed to the second pedestal 31 by the fixing member.

[0060] Next, in a state where the wheel 11, tread 12, and inner ring 15 are arranged so that the first outer peripheral surface and the third inner peripheral surface face each other and the other end E2 and the first inner peripheral surface 124 face each other, the second and third forces applied to the spokes 13 are removed, and the other ends E2 of the spokes 13 are pressed against the first inner peripheral surface 124 to bring them into close contact, thereby fixing the spokes 13 to the tread 12 (step S15). In a case where the tread 12 and the inner peripheral ring 15 are joined using the manufacturing device 3 and the wheel 11 and the inner peripheral ring 15 are joined separately, in step S15, the second and third forces applied to the spokes 13 are removed in a state where the tread 12 and the inner peripheral ring 15 are arranged so that the other ends E2 and the first inner peripheral surface 124 face each other. As an example, in the manufacturing apparatus 3, in a state where the wheel 11, the tread 12, and the inner ring 15 are arranged so that the first outer peripheral surface and the third inner peripheral surface face each other and the other end E2 and the first inner peripheral surface 124 face each other, as shown in FIG. 8B, the second rotating member 32 is rotated in the reverse direction of the arrow A5 to remove the second force from the spokes 13, and the third rotating member 33 is rotated in the reverse direction of the arrow A6 to remove the third force from the spokes 13 as shown in FIG. 8C. In a state where the second force and the third force are removed, the second distance D2 is longer than the radius B of the first inner peripheral surface 124, so that the other end E2 of the spokes 13 is pressed against the first inner peripheral surface 124 and fixed to the first inner peripheral surface 124. In addition, by pressing the other end E2 of the spokes 13 against the first inner peripheral surface 124, a tensile stress in the circumferential direction is generated in the tire cord 122a of the tread 12.

[0061] The airless tire manufactured by combining the wheel 11, the tread 12, and the inner ring 15 is removed from the manufacturing apparatus 3 by using the conveying mechanism 37 (step S16). In the case where only the tread 12 and the inner ring 15 are combined, the combined parts are removed from the manufacturing apparatus 3 by using the conveying mechanism 36. The removed airless tire is conveyed to the next step. Then, the conveying mechanism 37 conveys a new inner ring 15 (step S17). Thereafter, steps S12 to S17 are repeated until the desired number of airless tires are manufactured. Furthermore, in the case where the wheel 11, the tread 12, and the inner ring 15 are required, step S11 is executed as necessary.

[0062] The inner circumferential ring 15 may include an outer circumferential ring 16 having a second outer circumferential surface with a second diameter that is longer than the first diameter of the first inner circumferential surface 124 by a first predetermined length in addition to the multiple spokes 13. When the inner circumferential ring 15 includes the outer circumferential ring 16, the manufacturing device 3 applies a second force and a third force to the multiple spokes 13 so that the maximum value of the diameter of the second outer circumferential surface is less than the first diameter (step S13a). Next, the tread 12 and the inner circumferential ring 15 in a state in which the second force and the third force are applied to the multiple spokes 13 are arranged so that the first inner circumferential surface 124 and the second outer circumferential surface face each other (step S14-1a), and the wheel 11 and the inner circumferential ring 15 in a state in which the second force and the third force are applied to the multiple spokes 13 are arranged so that the first outer circumferential surface and the third inner circumferential surface face each other (step S14-2a). Then, the second and third forces applied to the spokes 13 are removed, and the second outer peripheral surface is pressed against the first inner peripheral surface 124 to make them adhere to each other (step S15a). That is, when the inner peripheral ring 15 includes the outer peripheral ring 16, in step S11, the inner peripheral ring 15 including the spokes 13 and the outer peripheral ring 16 is prepared, and steps S13 to S15 are replaced with steps S13a to S15a. In step S13a, it is not necessary to uniformly reduce the diameter of the second outer peripheral surface, and it is sufficient that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter. In addition, when the tread 12 and the inner peripheral ring 15 are joined using the manufacturing device 3 and the wheel 11 and the inner peripheral ring 15 are joined separately, step S14-2a is not performed and the wheel 11 is not arranged.

[0063] As an example, in the manufacturing apparatus 3, the conveying mechanism 37 is used to convey the inner ring 15 including the spokes 13 and the outer ring 16, and the second pin 34 and the third pin 35 are inserted between the adjacent spokes 13. Next, the second rotating member 32 is rotated clockwise on the XY plane, and the third rotating member 33 is rotated counterclockwise on the XY plane, and the second force is applied to the multiple spokes 13 in contact with the second pin 34, and the third force is applied to the multiple spokes 13 in contact with the third pin 35, so that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter. Next, the conveying mechanism 36 in a state in which the tread 12 is supported on the support portion 25a is moved from above to below the manufacturing apparatus 3 along the Z axis direction, and the tread 12 is arranged on the outside of the multiple spokes 13 to which the second force and the third force are applied, so that the first inner peripheral surface 124 and the second outer peripheral surface face each other. Next, the wheel 11 is transported using the transport mechanism 37, and the wheel 11 is disposed inside the inner ring 15 so that the first outer peripheral surface and the third inner peripheral surface face each other. Then, the second rotating member 32 is rotated counterclockwise on the XY plane, and the third rotating member 33 is rotated clockwise on the XY plane, thereby removing the second force and the third force from the spokes 13.

[0064] When the contact surface 123 of the tread 12 is worn, the tread 12 of the airless tire is replaced with another tread using the manufacturing device 3. For example, in a state in which the conveying mechanism 36 is moved downward in the Z-axis direction as shown in FIG. 8B, the wheel 11 of the airless tire is placed at the center of the conveying mechanism 36 by the conveying mechanism 37. Next, while the second rotating member 32 is stationary, the third rotating member 33 is rotated to apply a second force and a third force to the multiple spokes 13 fixed to the tread 12 so that the second distance D2 is less than the radius B of the first inner circumferential surface 124, thereby separating the multiple spokes 13 from the tread 12.

[0065] Next, another tread different from the separated tread 12 is placed on the support part 25a of the conveying mechanism 36, and the conveying mechanisms 36, 37 are moved to place the other tread and the inner ring 15 in a state in which the second force and the third force are applied to the multiple spokes 13 so that the second inner circumferential surface and the other end E2 face each other. Then, the third rotating member 33 is rotated in the reverse direction to remove the second force and the third force applied to the multiple spokes 13, and the multiple spokes 13 are fixed to the other tread. The airless tire in which the tread 12 has been replaced is taken out of the manufacturing apparatus 3 by the conveying mechanism 37. Note that, even when the inner ring 15 includes the outer ring 16, the tread 12 can be replaced in a similar manner. In this case, the inner ring 15 and the other tread are placed so that the second inner circumferential surface and the second outer circumferential surface face each other.

[0066] As shown in FIG. 1, when the airless tire includes the intermediate ring 14, the second and third forces may be applied to only some of the spokes 13 when the second distance D2 is made less than the radius B of the first inner circumferential surface 124 by applying the second and third forces to the spokes 13, as in the first embodiment. Also, as in the first embodiment, the spokes 13 may have a plurality of bent portions between one end and the other end that are bent in a direction connecting the one end and the other end, and the intermediate ring 14 may connect the bent portions of the spokes 13 to each other. When the spokes 13 have bent portions, the second force is applied to the first bent portion and the third force is applied to the second bent portion that is closer to the other end E2 than the first bent portion when the second and third forces are applied to the spokes 13 to make the second distance D2 less than the radius B of the first inner circumferential surface 124. In the case of the spokes 13 shown in FIG. 8A, the bent portion 134 is the first bent portion and the bent portion 135 is the second bent portion.

[0067] [Embodiments of the present invention] According to the present embodiment, there is provided a method for manufacturing an airless tire, which includes preparing a wheel 11 having a first outer peripheral surface and coupled to a vehicle, and a tread 12 having a first inner peripheral surface 124 and contacting a road surface, the wheel 11 includes a plurality of spokes 13 having one end joined to the first outer peripheral surface, extending radially from the first outer peripheral surface, and deformable in a circumferential direction of the wheel 11, a first distance D1 from a center C1 of the wheel 11 to the other end E1 of the plurality of spokes 13 is longer than a radius B of the first inner peripheral surface 124 by a first predetermined distance, a first force in the circumferential direction is applied to the plurality of spokes 13 so that the first distance D1 is less than the radius B, the tread 12 and the wheel 11 in a state in which the first force is applied to the plurality of spokes 13 are disposed such that the first inner peripheral surface 124 and the other end E1 face each other, and the first force applied to the plurality of spokes 13 is removed. This makes it possible to manufacture an airless tire that suppresses excessive deformation of the spokes 13.

[0068] In the manufacturing method of an airless tire of this embodiment, the wheel 11 is prepared, which includes the plurality of spokes 13 and an outer peripheral ring 16 that has a second outer peripheral surface having a second diameter that is longer than the first diameter of the first inner peripheral surface 124 by a predetermined length and connects the other end E1, the first force is applied to the plurality of spokes 13 so that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter, and the tread 12 and the wheel 11 in a state in which the first force is applied to the plurality of spokes 13 are arranged so that the first inner peripheral surface 124 and the second outer peripheral surface face each other. This increases the bonding area with the tread 12, improving the load-bearing capacity of the airless tire.

[0069] In the manufacturing method of an airless tire of this embodiment, the first force is applied to the multiple spokes 13 fixed to the tread 12 so that the first distance D1 is less than the radius B, the multiple spokes 13 are separated from the tread 12, another tread different from the tread 12 and the wheel 11 in a state in which the first force is applied to the multiple spokes 13 are arranged so that the second inner circumferential surface of the other tread faces the other end E1, and the first force applied to the multiple spokes 13 is removed to fix the multiple spokes to the other tread. This makes it possible to replace the tread 12 whose contact surface 123 has worn away.

[0070] In the manufacturing method for an airless tire of the present embodiment, the airless tire includes an intermediate ring 14 that connects the spokes 13 to each other, and the first force is applied to some of the spokes 13 among the plurality of spokes 13 such that the first distance D1 is less than the radius B. This makes it possible to further suppress excessive deformation of the spokes 13.

[0071] In the manufacturing method of an airless tire of this embodiment, the spokes 13 have multiple bent portions between the one end and the other end E1, and the bent portions are bent in a direction connecting the one end and the other end E1, and when the first force is applied to the multiple spokes 13 such that the first distance D1 is less than the radius B, the first force is applied to the bent portions. This makes it possible to reduce the first force required to deform the spokes 13.

[0072] In the manufacturing method for an airless tire of this embodiment, the airless tire includes an intermediate ring 14 that connects the bent portions of the spokes 13, and when the first force is applied to the plurality of spokes 13 so that the first distance D1 is less than the radius B, the first force is applied to the bent portions of some of the plurality of spokes 13. This makes it possible to further suppress excessive deformation of the spokes 13.

[0073] The manufacturing method of an airless tire of the present embodiment includes a first base 21 whose position is fixed, a fixing member 22 provided on the first base 21 and fixing the wheel 11 to the first base 21, a first rotating member 23 attached to the first base 21 so as to be rotatable in the circumferential direction, a plurality of first pins 24 extending in the width direction of the wheel 11 and fixed to the first rotating member 23 along the circumferential direction, the tread 12, and a conveying device for conveying the tread 12 when arranging the wheel 11 in a state in which the first force is applied to the plurality of spokes 13. Using a manufacturing device 2 equipped with feeding mechanisms 25, 26, the wheel 11 is fixed to the fixed member 22, the first pin 24 is inserted between adjacent spokes 13, the first rotating member 23 is rotated, the first force is applied to the plurality of spokes 13 in contact with the first pin 24 so that the first distance D1 is less than the radius B, the tread 12 is disposed outside the plurality of spokes 13 to which the first force is applied so that the first inner circumferential surface 124 and the other end E1 face each other, and the first rotating member 23 is rotated in the reverse direction to remove the first force. In this way, an airless tire in which excessive deformation of the spokes 13 is suppressed can be manufactured.

[0074] According to the present embodiment, the tread 12 having a first inner circumferential surface 124 and coming into contact with a road surface and the inner circumferential ring 15 having a third outer circumferential surface to which one ends of the plurality of spokes 13 are connected are prepared, the inner circumferential ring 15 includes a plurality of spokes 13 that extend radially from the third outer circumferential surface to which one ends are joined and that are deformable in the circumferential direction of the inner circumferential ring 15, and a second distance D2 from a center C2 of the inner circumferential ring 15 to the other ends E2 of the plurality of spokes 13 is set to be longer than a radius B of the first inner circumferential surface 124 by a second predetermined distance, and the second distance D2 is set to be less than the radius B. a second force in the circumferential direction is applied to first portions of the spokes 13, and a third force in the circumferential direction opposite to the second force is applied to second portions closer to the other end E2 than the first portions, the tread 12 and the inner ring 15 in a state in which the second force and the third force have been applied to the spokes 13 are disposed so that the other end E2 faces the first inner circumferential surface 124, and the second force and the third force applied to the spokes 13 are removed. This makes it possible to manufacture an airless tire in which excessive deformation of the spokes 13 is suppressed.

[0075] In the manufacturing method of an airless tire of this embodiment, the inner ring 15 is prepared, which includes the plurality of spokes 13 and an outer ring 16 having a second outer peripheral surface with a second diameter that is longer than the first diameter of the first inner peripheral surface 124 by a predetermined length and connecting the other end E2, and the second force is applied to the first portion and the third force is applied to the second portion so that the maximum value of the diameter of the second outer peripheral surface is less than the first diameter, and the tread 12 and the inner ring 15 in a state in which the second force and the third force have been applied to the plurality of spokes 13 are arranged so that the second outer peripheral surface faces the first inner peripheral surface 124. This increases the bonding area with the tread 12, improving the load-bearing capacity of the airless tire.

[0076] In the manufacturing method of an airless tire of this embodiment, the second force and the third force are applied to the multiple spokes 13 fixed to the tread 12 so that the second distance D2 is less than the radius B, thereby separating the multiple spokes 13 from the tread 12, and another tread different from the tread 12 and the inner ring 15 in a state in which the second force and the third force are applied to the multiple spokes 13 are arranged so that a second inner circumferential surface of the other tread faces the other end E2, and the second force and the third force applied to the multiple spokes 13 are removed to fix the multiple spokes 13 to the other tread. This makes it possible to replace the tread 12 whose contact surface 123 has been worn.

[0077] In the manufacturing method for an airless tire of this embodiment, the airless tire includes an intermediate ring 14 that connects the spokes 13 to each other, and the second force is applied to the first portion and the third force is applied to the second portion of some of the spokes 13 among the plurality of spokes 13 such that the second distance D2 is less than the radius B. This makes it possible to further suppress excessive deformation of the spokes 13.

[0078] In the manufacturing method of an airless tire of this embodiment, the spoke 13 has a plurality of bent portions between the one end and the other end E2, the bent portions are bent in a direction connecting the one end and the other end E2, and the second force is applied to a first bent portion and the third force is applied to a second bent portion closer to the other end E2 than the first bent portion so that the second distance D2 is less than the radius B. This makes it possible to reduce the second and third forces required to deform the spoke 13.

[0079] In the manufacturing method for an airless tire of this embodiment, the airless tire includes an intermediate ring 14 that connects the bent portions of the spokes 13, and the second force is applied to the first bent portion and the third force is applied to the second bent portion of some of the spokes 13 among the plurality of spokes 13 such that the second distance D2 is less than the radius B. This makes it possible to further suppress excessive deformation of the spokes 13.

[0080] In the manufacturing method of the airless tire of the present embodiment, a manufacturing apparatus 3 is used that includes a second base 31 having a fixed position, a second rotating member 32 attached to the second base 31 so as to be rotatable in the circumferential direction, a third rotating member 33 attached to the second base 31 so as to be rotatable in the circumferential direction and disposed on the outer side of the second rotating member 32, a plurality of second pins 34 extending in the width direction of the inner circumferential ring 15 and fixed to the second rotating member 32 along the circumferential direction, a plurality of third pins 35 extending in the width direction of the inner circumferential ring 15 and fixed to the third rotating member 33 along the circumferential direction, a wheel 11 to be coupled to a vehicle, the tread 12, and conveying mechanisms 36, 37 that convey the wheel 11 and the tread 12 when arranging the plurality of spokes 13 to which the second force and the third force are applied. 35 is inserted through the spoke 11, the second rotating member 32 is rotated in a first direction to apply the second force to the first portion in contact with the second pin 34, and the third rotating member 33 is rotated in a second direction opposite to the first direction to apply the third force to the second portion in contact with the third pin 35 so that the second distance D2 is less than the radius B, the wheel 11 is disposed inside the inner ring 15 in a state in which the second force and the third force are applied to the plurality of spokes 13 so that a first outer peripheral surface of the wheel 11 and a third inner peripheral surface of the inner ring 15 face each other, and the tread 12 is disposed outside the inner ring 15 in a state in which the second force and the third force are applied to the plurality of spokes 13 so that the other end E2 and the first inner peripheral surface 124 face each other, and the second rotating member 32 is rotated in the second direction and the third rotating member 33 is rotated in the first direction to remove the second force and the third force. This makes it possible to manufacture an airless tire that suppresses excessive deformation of the spokes 13.

[0081] In the manufacturing method of an airless tire of this embodiment, the tread 12 has a first elastic portion 121 made of an elastic material, and a first reinforcing layer 122 extending in the width direction of the tread 12 and having higher rigidity than the first elastic portion 121, and the first reinforcing layer 122 is disposed at a position closer to the first inner circumferential surface 124 than a contact surface 123 that contacts the road surface. This makes it possible to further suppress excessive deformation of the spokes 13.

[0082] In the manufacturing method of an airless tire of this embodiment, the outer circumferential ring 16 has a second elastic portion 161 made of an elastic material, and a second reinforcing layer 162 extending in the width direction of the outer circumferential ring 16 and having higher rigidity than the second elastic portion 161. This makes it possible to further suppress excessive deformation of the spokes 13.

[0083] Also, according to this embodiment, there is provided an airless tire manufacturing apparatus 2 including a plurality of spokes 13 extending radially from a first outer circumferential surface of a wheel 11 coupled to a vehicle toward a first inner circumferential surface 124 of a tread 12 that comes into contact with a road surface and that are deformable in the circumferential direction of the wheel 11, with one end of the plurality of spokes 13 being joined to the first outer circumferential surface, the airless tire manufacturing apparatus 2 including a first base 21 having a fixed position, a fixing member 22 provided on the first base 21 and fixing the wheel 11 to the first base 21, a first rotating member 23 attached to the first base 21 so as to be rotatable in the circumferential direction, a plurality of first pins 24 extending in the width direction of the wheel 11 and fixed to the first rotating member 23 along the circumferential direction, and a conveying mechanism for conveying the tread 12 when the wheel 11 and the tread 12 are arranged. and a feed mechanism 25, 26, which fixes the wheel 11 to the fixed member 22, inserts the first pin 24 between adjacent spokes 13 among the plurality of spokes 13, rotates the first rotating member 23 to apply the first force in the circumferential direction to the plurality of spokes 13 in contact with the first pin 24 so that a first distance D1 between the center of the wheel 11 to which the one end is joined and the other end E1 of the plurality of spokes 13, which is longer than the radius B of the first inner circumferential surface 124 by a first predetermined distance, is less than the radius B, and disposes the tread 12 and the wheel 11 in a state in which the first force is applied to the plurality of spokes 13 such that the first inner circumferential surface 124 and the other end E1 face each other, and rotates the first rotating member 23 in the reverse direction to remove the first force. This makes it possible to manufacture an airless tire in which excessive deformation of the spokes 13 is suppressed.

[0084] According to the present embodiment, there is provided an airless tire manufacturing apparatus 3 including an inner circumferential ring 15 connecting one ends of a plurality of spokes 13, and a plurality of the spokes 13 extending radially from a third outer circumferential surface of the inner circumferential ring 15 toward a first inner circumferential surface 124 of the tread 12 that comes into contact with a road surface and that are deformable in a circumferential direction of the inner circumferential ring 15, the airless tire manufacturing apparatus 3 including a second pedestal 31 whose position is fixed, a second rotating member 32 attached to the second pedestal 31 so as to be rotatable in the circumferential direction, and a second rotating member 32 attached to the second pedestal 31 so as to be rotatable in the circumferential direction. a third rotating member 33 disposed outside the second rotating member 32; a plurality of second pins 34 extending in the width direction of the inner ring 15 and fixed to the second rotating member 32 along the circumferential direction; a plurality of third pins 35 extending in the width direction of the inner ring 15 and fixed to the third rotating member 33 along the circumferential direction; and conveying mechanisms 36, 37 for conveying the tread 12 and the inner ring 15 when the tread 12 and the inner ring 15 are arranged, the second pin 34 and the third pin 35 are inserted between adjacent spokes 13 among the spokes 13, and the second rotating member 32 is rotated in a first direction to apply the second circumferential force to a first portion of the spokes 13 that is in contact with the second pin 34, so that a second distance D2 between the center of the inner ring 15 to which the one ends are joined and the other ends E2 of the multiple spokes 13, the second distance D2 being longer than the radius B of the first inner circumferential surface 124 by a second predetermined distance, is less than the radius B, and the third rotating member 33 is rotated in a second direction opposite to the first direction. an airless tire manufacturing device 3 is provided, which rotates the spokes 13 to apply a third force along the circumferential direction and in a direction opposite to the second force to second portions of the spokes 13 that contact the third pins 35, arranges the tread 12 and the inner ring 15 in a state in which the second force and the third force have been applied to the plurality of spokes 13 so that the other end E2 faces the first inner circumferential surface 124, and rotates the second rotating member 32 in the second direction and rotates the third rotating member 33 in the first direction to remove the second force and the third force. This makes it possible to manufacture an airless tire in which excessive deformation of the spokes 13 is suppressed. [Explanation of symbols]

[0085] Reference Signs List 1, 1a... airless tire, 11... wheel, 111... disk, 112... rim, 12... tread, 121... first elastic portion, 122... first reinforcing layer, 122a... tire cord, 123... ground contact surface, 124... first inner circumferential surface, 13... spokes, 131, 132, 133, 134, 135... bending portion, 14, 14a, 14b, 14c... intermediate ring, 15... inner circumferential ring, 16... outer circumferential ring, 161... second elastic portion, 162... second reinforcing layer, 162a... tire cord 2... manufacturing device, 21... first base, 22... fixed member, 23... first rotating member, 24... first pin, 25, 26... conveying mechanism, 25a... support portion 3... manufacturing device, 31... second base, 32... second rotating member, 33... third rotating member, 34... second pin, 35... third pin, 36, 37... conveying mechanism, 36a... support portion A1, A2, A3, A4, A5, A6...arrows, B...radius of first inner surface, C1...center of wheel, C2...center of inner ring, D1...first distance, D2...second distance, E1, E2...other end

Claims

1. A wheel having a first outer circumferential surface and coupled to a vehicle, and a tread having a first inner circumferential surface and contacting a road surface, the wheel having a plurality of spokes, one end of which is joined to the first outer circumferential surface, which extend radially from the first outer circumferential surface and are deformable in a circumferential direction of the wheel, a first distance from a center of the wheel to the other end of each of the plurality of spokes being longer than a radius of the first inner circumferential surface by a first predetermined distance, applying the first circumferential force to the plurality of spokes such that the first distance is less than the radius; the tread and the wheel in a state in which the first force is applied to the plurality of spokes are disposed such that the first inner circumferential surface and the other end face each other; removing the first force applied to the plurality of spokes.

2. preparing the wheel including a plurality of the spokes and an outer peripheral ring having a second outer peripheral surface with a second diameter that is longer than the first diameter of the first inner peripheral surface by a predetermined length and connecting the other ends; applying the first force to the plurality of spokes such that a maximum diameter of the second outer circumferential surface is less than the first diameter; 2. The method for manufacturing an airless tire according to claim 1, wherein the tread and the wheel in a state in which the first force is applied to the plurality of spokes are disposed so that the first inner circumferential surface and the second outer circumferential surface face each other.

3. applying the first force to a plurality of the spokes fixed relative to the tread to separate the plurality of the spokes from the tread such that the first distance is less than the radius; a second inner circumferential surface of the second tread and the wheel in a state in which the first force is applied to the plurality of spokes are disposed so that the second inner circumferential surface of the second tread faces the other end of the second tread; The method for manufacturing an airless tire according to claim 1 , further comprising removing the first force applied to the plurality of spokes to fix the plurality of spokes to the another tread.

4. The airless tire includes an intermediate ring that connects the spokes to each other, The method for manufacturing an airless tire according to claim 1 , wherein the first force is applied to some of the spokes such that the first distance is less than the radius.

5. The spoke has a plurality of bends between the one end and the other end, The bent portion is bent in a direction connecting the one end and the other end, The method for manufacturing an airless tire according to claim 1 , wherein when the first force is applied to the plurality of spokes such that the first distance is less than the radius, the first force is applied to the bent portion.

6. The airless tire includes an intermediate ring that connects the bent portions of the spokes to each other, The method for manufacturing an airless tire according to claim 5 , wherein, when the first force is applied to the plurality of spokes such that the first distance is less than the radius, the first force is applied to the bent portions of some of the plurality of spokes.

7. a first base having a fixed position; A fixing member provided on the first base and fixing the wheel to the first base; a first rotating member attached to the first base so as to be rotatable in the circumferential direction; a plurality of first pins extending in a width direction of the wheel and fixed to the first rotating member along the circumferential direction; a manufacturing device including the tread and a conveying mechanism that conveys the tread when arranging the wheel in a state in which the first force is applied to the plurality of spokes, The wheel is fixed to the fixed member, and the first pin is inserted between adjacent spokes; rotating the first rotating member to apply the first force to a plurality of the spokes contacting the first pin such that the first distance is less than the radius; the tread is disposed on an outer side of the plurality of spokes to which the first force is applied, such that the first inner circumferential surface faces the other end; The method for manufacturing an airless tire according to claim 1 , further comprising: rotating the first rotating member in a reverse direction to remove the first force.

8. a tread having a first inner peripheral surface and contacting a road surface; and an inner ring having a third outer peripheral surface to which one ends of a plurality of spokes are connected, the inner ring having a plurality of spokes extending radially from the third outer peripheral surface to which one ends are connected and deformable in a circumferential direction of the inner ring, a second distance from a center of the inner ring to the other ends of the plurality of spokes being longer than a radius of the first inner peripheral surface by a second predetermined distance; applying a second force in the circumferential direction to a first portion of the spokes and applying a third force along the circumferential direction and opposite to the second force to a second portion of the spokes that is closer to the other end than the first portion, such that the second distance is less than the radius; the tread and the inner circumferential ring in a state in which the second force and the third force are applied to the plurality of spokes are disposed such that the other end faces the first inner circumferential surface; removing the second force and the third force applied to the plurality of spokes.

9. preparing an inner ring including a plurality of the spokes and an outer ring having a second outer circumferential surface with a second diameter that is longer than the first diameter of the first inner circumferential surface by a predetermined length and connecting the other ends; applying the second force to the first portion and applying the third force to the second portion such that a maximum diameter of the second outer circumferential surface is less than the first diameter; 9. The method for manufacturing an airless tire according to claim 8, wherein the tread and the inner ring in a state in which the second force and the third force are applied to the plurality of spokes are disposed so that the second outer peripheral surface and the first inner peripheral surface face each other.

10. applying the second and third forces to a plurality of the spokes fixed relative to the tread to separate the plurality of the spokes from the tread such that the second distance is less than the radius; a second inner circumferential surface of the inner ring and a second inner circumferential surface of the inner ring are disposed in a direction opposite to the second inner circumferential surface of the spoke; The method for manufacturing an airless tire according to claim 8 , further comprising removing the second force and the third force applied to the plurality of spokes to fix the plurality of spokes to the another tread.

11. The airless tire includes an intermediate ring that connects the spokes to each other, 9. The method for manufacturing an airless tire according to claim 8, wherein the second force is applied to the first portion and the third force is applied to the second portion of some of the spokes, such that the second distance is less than the radius.

12. The spoke has a plurality of bends between the one end and the other end, The bent portion is bent in a direction connecting the one end and the other end, 9. The method for manufacturing an airless tire according to claim 8, wherein the second force is applied to a first bent portion, and the third force is applied to a second bent portion that is closer to the other end than the first bent portion, so that the second distance is less than the radius.

13. The airless tire includes an intermediate ring that connects the bent portions of the spokes to each other, 13. The method for manufacturing an airless tire according to claim 12, wherein the second force is applied to the first bent portion and the third force is applied to the second bent portion in some of the spokes among the plurality of spokes such that the second distance is less than the radius.

14. a second base having a fixed position; A second rotating member attached to the second base so as to be rotatable in the circumferential direction; a third rotating member that is rotatably attached to the second base in the circumferential direction and disposed outside the second rotating member; a plurality of second pins extending in a width direction of the inner circumferential ring and fixed to the second rotating member along the circumferential direction; a plurality of third pins extending in a width direction of the inner circumferential ring and fixed to the third rotating member along the circumferential direction; a manufacturing device including a wheel to be coupled to a vehicle, the tread, and a conveying mechanism for conveying the wheel and the tread when arranging the inner ring in a state in which the second force and the third force are applied to the plurality of spokes, The second pin and the third pin are inserted between adjacent spokes, rotating the second rotating member in a first direction to apply the second force to the first portion in contact with the second pin, and rotating the third rotating member in a second direction opposite to the first direction to apply the third force to the second portion in contact with the third pin, such that the second distance is less than the radius; the wheel is disposed inside the inner ring in a state in which the second force and the third force are applied to the plurality of spokes, such that a first outer peripheral surface of the wheel faces a third inner peripheral surface of the inner ring; and the tread is disposed outside the spokes in a state in which the second force and the third force are applied, such that the other ends of the spokes face the first inner peripheral surface; The method for manufacturing an airless tire according to claim 8 , further comprising rotating the second rotating member in the second direction and rotating the third rotating member in the first direction to remove the second force and the third force.

15. The tread has a first elastic portion made of an elastic material, and a first reinforcing layer extending in a width direction of the tread and having a higher rigidity than the first elastic portion, The method for manufacturing an airless tire according to any one of claims 1 to 14, wherein the first reinforcing layer is disposed at a position closer to the first inner circumferential surface than a contact surface that comes into contact with a road surface.

16. 10. The method for manufacturing an airless tire according to claim 2, wherein the outer peripheral ring has a second elastic portion made of an elastic material, and a second reinforcing layer extending in a width direction of the outer peripheral ring and having a higher rigidity than the second elastic portion.

17. An apparatus for manufacturing an airless tire, comprising: a plurality of spokes extending radially from a first outer circumferential surface of a wheel coupled to a vehicle toward a first inner circumferential surface of a tread that comes into contact with a road surface and deformable in a circumferential direction of the wheel, one ends of the plurality of spokes being joined to the first outer circumferential surface, a first base having a fixed position; A fixing member provided on the first base and fixing the wheel to the first base; a first rotating member attached to the first base so as to be rotatable in the circumferential direction; a plurality of first pins extending in a width direction of the wheel and fixed to the first rotating member along the circumferential direction; a conveying mechanism that conveys the tread when the wheel and the tread are disposed, The wheel is fixed to the fixed member, and the first pin is inserted between adjacent spokes among the plurality of spokes; rotating the first rotating member to apply a first force in the circumferential direction to the plurality of spokes in contact with the first pin so that a first distance between a center of the wheel to which the one ends are joined and the other ends of the plurality of spokes, the first distance being longer than a radius of the first inner circumferential surface by a first predetermined distance, is less than the radius; the tread and the wheel in a state in which the first force is applied to the plurality of spokes are disposed such that the first inner circumferential surface and the other end face each other; and rotating the first rotating member in a reverse direction to remove the first force.

18. An airless tire manufacturing apparatus comprising: an inner circumferential ring connecting one ends of a plurality of spokes; and a plurality of spokes extending radially from a third outer circumferential surface of the inner circumferential ring toward a first inner circumferential surface of a tread that comes into contact with a road surface and capable of deforming in a circumferential direction of the inner circumferential ring, a second base having a fixed position; A second rotating member attached to the second base so as to be rotatable in the circumferential direction; a third rotating member that is rotatably attached to the second base in the circumferential direction and disposed outside the second rotating member; a plurality of second pins extending in a width direction of the inner circumferential ring and fixed to the second rotating member along the circumferential direction; a plurality of third pins extending in a width direction of the inner circumferential ring and fixed to the third rotating member along the circumferential direction; a conveying mechanism that conveys the tread and the inner ring when the tread and the inner ring are disposed, the second pin and the third pin are inserted between adjacent spokes among the plurality of spokes having one ends joined to the third outer peripheral surface; rotating the second rotating member in a first direction to apply the second circumferential force to a first portion of the spoke that contacts the second pin, and rotating the third rotating member in a second direction opposite to the first direction to apply a third force along the circumferential direction and in a direction opposite to the second force, to a second portion of the spoke that contacts the third pin, so that a second distance between a center of the inner ring to which the one ends are joined and the other ends of the multiple spokes, the second distance being longer than the radius of the first inner circumferential surface by a second predetermined distance, is less than the radius; the tread and the inner circumferential ring in a state in which the second force and the third force are applied to the plurality of spokes are disposed such that the other end faces the first inner circumferential surface; The second rotating member is rotated in the second direction and the third rotating member is rotated in the first direction to remove the second force and the third force.

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