JP2012187982A - Tire/wheel assembly - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire/wheel assembly suitable for an in-wheel motor system, in which stiffness in a longitudinal direction is appropriately low to secure an appropriate ground contact area and good transmission of force in a circumferential direction is achieved.SOLUTION: A tire/wheel assembly 10 includes: a cylindrical annular structure 11; a porous resin material layer 15 provided in an outer circumferential part of the annular structure 11, in the circumferential direction of the annular structure 11; a rubber material layer 14 provided outside the porous resin material layer 15; and a plurality of curved metal blade members 13 which are provided between the annular structure 11 and a motor 20 disposed inside the annular structure 11 and transmits rotation of a rotor 20R of the motor 20 to the annular structure 11.

Description

  The present invention relates to a pneumatic tire.

  As measures against global warming, in order to reduce the amount of carbon dioxide generated from automobiles, the combined use of electric motors and gasoline engines (hybrid vehicles) and the use of electric motors (electric vehicles) are progressing. When using an electric motor as a power generation source of a vehicle, an in-wheel motor system in which an electric motor and a brake device are incorporated in a wheel space is known (Patent Documents 1 and 2). Moreover, since the in-wheel motor system has a structure in which an electric motor is arranged inside the wheel, the heat generated by the electric motor tends to be trapped inside the wheel. For this reason, the structure which is easy to radiate the heat which the electric motor generated is desired. As techniques for improving heat dissipation in the in-wheel motor system, techniques as described in Patent Documents 3 and 4 are known. The in-wheel motor system can eliminate power transmission parts such as a drive shaft and a differential gear, and can secure a large volume in the vehicle body, thus contributing to a compact vehicle. Further, the in-wheel motor system is easy to control and drive the steered wheels, and can exhibit a steering performance that is not found in conventional vehicles, and is attracting attention as a future EV (Electric Vehicle) system. For example, a vehicle equipped with in-wheel motors on four wheels or left and right wheels can perform high-level vehicle attitude control using the high responsiveness of the motor, accuracy of generated torque, and forward / reverse rotation characteristics, and high vehicle motion performance Can be expected to demonstrate.

JP 2004-152416 A JP 2004-1115014 A JP-A-5-104969 JP 2006-246678 A

  An in-wheel motor vehicle may increase the unsprung mass and reduce the grounding characteristics and ride comfort as the motor is mounted in the wheel compared to a vehicle having a motor in the vehicle body.

  In-wheel motor vehicles need to transmit fluctuations in rotational torque to the road surface without delay in order to exhibit the high responsiveness of the electric motor. For this reason, the in-wheel motor vehicle requires the tire / wheel assembly to have high rotational rigidity and low loss characteristics. In-wheel motor vehicles require the tire / wheel assembly to have stable contact characteristics (friction) between the tire and the road surface.

  On the other hand, since the unsprung mass of an in-wheel motor vehicle is large, it is preferable that the tire / wheel assembly be lightened as much as possible. In addition, the tire / wheel assembly is also required to reduce deterioration in ride comfort performance as much as possible without increasing the vertical rigidity more than necessary.

  The balance of rigidity required for a tire / wheel assembly used in an in-wheel motor vehicle has an optimal uniform contact pressure, high tire responsiveness in the tire circumferential direction, and rigidity in the tire vertical direction. The stiffness balance is moderately low. However, as a characteristic of the pneumatic tire, the rigidity varies due to the variation in air pressure. For this reason, the pneumatic tire cannot control the longitudinal stiffness, the lateral stiffness, and the circumferential stiffness independently, and if the air pressure is increased, the longitudinal stiffness, the lateral stiffness, and the circumferential stiffness are increased. In addition, the techniques described in Patent Documents 3 and 4 are large-scale devices and are not practical.

  The present invention has been made in view of the above, and is suitable for an in-wheel motor system in which longitudinal rigidity is moderately low, an appropriate ground contact area can be secured, and force transmission in the circumferential direction is good. It is an object to provide a tire / wheel assembly.

  Means for solving the above-described problems include a cylindrical annular structure, a porous resin material layer provided on an outer peripheral portion of the annular structure in a circumferential direction of the annular structure, and the porous An electric motor provided on an outer peripheral portion of the material layer between a rubber material layer provided in a circumferential direction of the annular structure, and the electric motor disposed inside the annular structure and the annular structure; And a plurality of curved metal spring members for transmitting the rotation of the rotor to the annular structure.

  As a more preferable aspect of the above-mentioned means, the structure is a cylindrical structure, and has an inner annular structure that is disposed inside the annular structure and connects the plurality of metal spring members, and the inner annular structure. Is preferably connected to the rotor.

  As a more preferable aspect of the above-described means, the material of the annular structure is desirably stainless steel or steel having a thickness of 0.2 mm to 1.0 mm.

  As a more preferable aspect of the above-described means, it is desirable that the material of the annular structure is stainless steel or steel or aluminum or aluminum alloy having a thickness greater than 1.0 mm and not greater than 5.0 mm.

  The present invention provides a tire / wheel assembly suitable for an in-wheel motor system, in which the rigidity in the vertical direction is moderately low, an appropriate ground contact area can be secured in the ground contact portion, and the force transmission in the circumferential direction is good. Can be provided.

FIG. 1 is a front view of a tire / wheel assembly according to the present embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. FIG. 3 is a perspective view of the annular structure. FIG. 4 is a cross-sectional view showing an annular structure, a porous resin material layer, and a rubber material layer. FIG. 5 is a partial side view showing the annular structure, the inner annular structure, and the metal spring member. FIG. 6 is an explanatory view showing a modified example of the arrangement of the metal spring members. FIG. 7 is an explanatory view showing a modified example of the arrangement of the metal spring members. FIG. 8 is an explanatory view showing a modification of the arrangement of the metal spring members. 9 is a cross-sectional view taken along line BB in FIG. FIG. 10 is a side view showing an inner rotor type electric motor. 11 is a cross-sectional view taken along the line BB in FIG. FIG. 12 is a cross-sectional view showing a state where the tire / wheel assembly according to the present embodiment is attached to an inner rotor type electric motor.

  DESCRIPTION OF EMBODIMENTS Hereinafter, modes (embodiments) for carrying out the present invention will be described in detail with reference to the drawings. The present invention is not limited by the contents described in the following embodiments. The constituent elements described below include those that can be easily assumed by those skilled in the art and those that are substantially the same. Furthermore, the constituent elements described below can be appropriately combined.

  FIG. 1 is a front view of a tire / wheel assembly according to the present embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. The tire / wheel assembly 10 is attached to and driven by an electric motor 20 for running the vehicle, for example. The vehicle travel device 100 is configured by combining the tire / wheel assembly 10 and the electric motor 20. The tire / wheel assembly 10 includes an annular structure 11, a porous resin material layer 15, a rubber material layer 14, and a metal spring member 13. In this embodiment, the tire / wheel assembly 10 further includes an inner annular structure 12, although this is not necessary.

  The annular structure 11 is a cylindrical structure. The porous resin material layer 15 is provided on the outer periphery of the annular structure 11 in the circumferential direction of the annular structure 11. The rubber material layer 14 is provided on the outer peripheral portion of the porous material layer 15 toward the circumferential direction of the annular structure 11. The surface of the rubber material layer 14 becomes a tread surface that contacts the road surface. The metal spring member 13 is a curved member. A plurality of metal spring members 13 are provided between the annular structure 11 and the electric motor 20 disposed inside the annular structure 11, and transmit the rotation of the rotor 20 </ b> R of the electric motor 20 to the annular structure 11. The inner annular structure 12 is a cylindrical structure disposed inside the annular structure 11, and is made of a metal material in the same manner as the annular structure 11. The inner annular structure 12 connects a plurality of metal spring members 13. The inner annular structure 12 is connected to the rotor 20R. When the metal spring member 13 is directly connected to the rotor 20R, the inner annular structure 12 is not necessary.

  As shown in FIGS. 1 and 2, the electric motor 20 is an outer rotor type electric motor in which the rotor 20 </ b> R is disposed outside the stator 20 </ b> S. The electric motor 20 is used in a so-called in-wheel motor system that is attached to a vehicle suspension. The rotor 20 </ b> R includes a rotor case 21 that is an annular structure, and a permanent magnet 22 that is attached to the inner periphery of the rotor case 21. The permanent magnet 22 has S poles and N poles arranged alternately in the circumferential direction of the rotor case 21. A shaft 25 is attached to the center of the rotor case 21.

  The stator 20S is disposed inside the permanent magnet 22 included in the rotor 20R. In the stator 20 </ b> S, a plurality of coils 23 are provided on the outer peripheral portion of the stator body 24. The stator body 24 has a bearing 26 at the center. The shaft 25 described above is supported by the stator main body 24 via a bearing 26. With such a structure, the rotor 20R can rotate around the stator body 24 about the rotation axis Z. In the present embodiment, since the tire / wheel assembly 10 is attached to the outside of the rotor 20R via the inner annular structure 12, the tire / wheel assembly 10 is rotated when the rotor 20R of the electric motor 20 rotates. The motor 20 rotates around the rotation axis Z together with the rotor 20R.

  FIG. 3 is a perspective view of the annular structure. FIG. 4 is a cross-sectional view showing an annular structure, a porous resin material layer, and a rubber material layer. FIG. 5 is a partial side view showing the annular structure, the inner annular structure, and the metal spring member. As shown in FIG. 3, the annular structure 11 has a constant width (dimension in a direction parallel to the rotation axis Z of the annular structure 11) W in the circumferential direction. In this embodiment, the annular structure 11 is manufactured with metal materials, such as steel, stainless steel, or an aluminum alloy, for example.

  The elastic modulus of the annular structure 11 is preferably 70 GPa or more and 250 GPa or less. In addition, the thickness t of the annular structure 11 is preferably set to an appropriate size depending on the type of material of the annular structure 11 in the range of 0.1 mm to 5.0 mm. The product (referred to as a stiffness parameter) of the elastic modulus and thickness t of the annular structure 11 is preferably 10 or more and 500 or less. By setting the stiffness parameter in the above range, the annular structure 11 has a greater stiffness in the meridional section. For this reason, when the rubber material layer 14 that becomes the tread portion of the tire / wheel assembly 10 comes in contact with the road surface, the annular structure 11 suppresses deformation in the meridional section of the rubber material layer 14 that becomes the tread portion. . As a result, in the tire / wheel assembly 10, loss of viscoelastic energy due to the deformation is suppressed. Moreover, the rigidity in the radial direction of the annular structure 11 is reduced by setting the rigidity parameter within the above range. For this reason, in the tire / wheel assembly 10, the tread portion is flexibly deformed at the contact portion with the road surface, similarly to the conventional pneumatic tire. With such a function, the tire / wheel assembly 10 is eccentrically deformed while avoiding local strain and stress concentration in the ground contact portion, so that the strain in the ground contact portion can be dispersed. As a result, in the tire / wheel assembly 10, local deformation of the rubber material layer 14 in the ground contact portion is suppressed, so that a ground contact area is ensured and rolling resistance is reduced.

  Furthermore, since the tire / wheel assembly 10 has a large rigidity in the meridional section of the annular structure 11 and can secure the ground contact area of the rubber material layer 14, the ground contact length in the circumferential direction can be secured. Lateral force generated when input is increased. As a result, the tire / wheel assembly 10 can obtain a large cornering power.

  When the thickness of the annular structure 11 (the dimension in the radial direction of the annular structure 11) t is 0.2 mm or more and 1.0 mm or less, the material of the annular structure 11 is stainless steel or steel. When the thickness t of the annular structure 11 (dimension in the radial direction of the annular structure 11) t is greater than 1.0 mm and 5.0 mm or less, the material of the annular structure 11 is stainless steel, steel, or aluminum alloy. By doing in this way, it becomes easy to set a rigidity parameter in the range mentioned above.

  The rubber material layer 14 shown in FIG. 4 becomes the tread portion of the tire / wheel assembly 10 as described above. For the rubber material layer 14, a rubber material similar to that of a conventional pneumatic tire can be used. Although omitted in FIG. 4, it is preferable to provide a main groove or a lug groove on the surface (outer peripheral surface) of the rubber material layer 14 to form a tread pattern. For example, high pressure foamed urethane can be used for the porous resin material layer 15 shown in FIG. By using such a porous resin material layer 15, the tire / wheel assembly 10 can more effectively absorb the force that it receives from the road surface. The porous resin material layer 15 and the annular structure 11 can be bonded with an adhesive, for example. Moreover, the porous resin material layer 15 and the rubber material layer 14 can be joined with an adhesive, for example.

  As shown in FIG. 5, the metal spring member 13 is a member having an arcuate cross section. As the material of the metal spring member 13, for example, a metal material suitable for the spring such as steel, stainless steel, spring steel, or the like is used. Moreover, in this embodiment, the inner side annular structure 12 is manufactured with metal materials, such as steel, stainless steel, or an aluminum alloy, for example. As described above, the metal spring member 13 is disposed between the annular structure 11 and the inner annular structure 12. Then, one end 13TA of the metal spring member 13 is fixed to the inner peripheral surface of the annular structure 11, and the other end 13TB is fixed to the outer peripheral surface of the inner annular structure 12. With such a structure, the plurality of metal spring members 13 connect the annular structure 11 and the inner annular structure 12.

  The metal spring member 13, the annular structure 11, and the inner annular structure 12 are preferably fixed by, for example, screwing, welding, caulking, or the like. If it does in this way, these can be fixed reliably. Further, the screwing has an advantage that the metal spring member 13, the annular structure 11 and the inner annular structure 12 can be disassembled. When the inner annular structure 12 is not used, the metal spring member 13 is directly attached to the rotor case 21 of the electric motor 20. Also in this case, both are fixed by screwing, welding, caulking or the like.

  The plurality of metal spring members 13 have portions corresponding to arcuate curved portions directed in the circumferential direction of the annular structure 11 and the inner annular structure 12 (directions indicated by arrows C in FIG. 5), and correspond to arc strings. The portion to be made becomes substantially parallel to the radial direction of the annular structure 11 and the inner annular structure 12. With such a structure, the force received by the tire / wheel assembly 10 from the road surface is absorbed by the metal spring member 13 being bent. As described above, by using the metal spring member 13, the tire / wheel assembly 10 can appropriately reduce the rigidity in the vertical direction.

  The metal spring member 13 has a length direction (a direction orthogonal to the end surface of the arc shape) arranged substantially parallel to the width direction of the annular structure 11 and the inner annular structure 12. The metal spring member 13 has high rigidity in the length direction, but low rigidity in the direction in which the portion corresponding to the arc chord is expanded and contracted. For this reason, by arranging the portion corresponding to the curved portion of the arc of the metal spring member 13 in the circumferential direction of the annular structure 11 and the inner annular structure 12, the lateral rigidity of the tire / wheel assembly 10 is increased, And longitudinal rigidity can be made low moderately.

  The metal spring member 13 transmits a force between the annular structure 11 and the inner annular structure 12. That is, the metal spring member 13 transmits the driving force from the electric motor 20 to the rubber material layer 14 via the annular structure 11 and the braking force from the rubber material layer 14 via the annular structure 11. Or to 20. By using the metal spring member 13, the tire / wheel assembly 10 improves the force transmission efficiency in the circumferential direction between the annular structure 11 and the inner annular structure 12. The width of the metal spring member 13 (dimension in the direction parallel to the rotation axis Z of the annular structure 11) is set to an appropriate size within the width W of the annular structure 11. The thickness of the metal spring member 13 takes into consideration the magnitude of power transmitted between the electric motor 20 and the annular structure, the magnitude of impact force absorbed by the metal spring member 13, the material of the metal spring member 13, and the like. Determined.

  In the present embodiment, the annular structure 11, the metal spring member 13, and the inner annular structure 12 are all metal materials. For this reason, it is a structure where the heat of the electric motor 20 is easily transmitted to these. The heat generated when the electric motor 20 generates power is transmitted to the metal spring member 13 through the inner annular structure 12. The metal spring member 13 radiates this heat into the air. Since the tire / wheel assembly 10 includes the plurality of metal spring members 13, the heat dissipation area can be increased. Moreover, since the metal spring member 13 rotates, the heat dissipation effect to air improves. Furthermore, since heat is also radiated from the annular structure 11 to which heat is transmitted from the inner annular structure 12 and the metal spring member 13, the tire / wheel assembly 10 can effectively radiate the heat of the electric motor 20.

  In the case of the in-wheel motor system, since the electric motor is disposed in the wheel, heat generated by the electric motor tends to be trapped. As described above, the tire / wheel assembly 10 can effectively dissipate the heat of the electric motor 20 into the air by the plurality of metal spring members 13. Thus, the tire / wheel assembly 10 is suitable for the in-wheel motor system.

  6-8 is explanatory drawing which shows the modification of arrangement | positioning of a metal spring member. 9 is a cross-sectional view taken along line BB in FIG. As shown in FIG. 6, the metal spring members 13 having a circular arc cross section may have the convex sides of the arcs opposed to each other in a pair of adjacent metal spring members 13. In this way, when the metal spring member 13 transmits the driving force from the electric motor 20 to the annular structure 11 and when the metal spring member 13 transmits the braking force from the rubber material layer 14 to the electric motor 20, the tensile force is applied. The number of metal spring members 13 responsible for the force and the number of metal spring members 13 responsible for the compression force can be made equal. Further, as shown in FIG. 7, both end portions of the metal spring member 13a having a circular arc shape in cross section are fixed to the inner annular structure 12 (shown in FIG. 1 or the rotor case 21 of the electric motor 20), and the convex portion of the metal spring member 13a. May be fixed to the annular structure 11.

  The metal spring member 13b having a circular arc shape shown in FIG. 9 is obtained by rotating the arrangement direction of the metal spring member 13 shown in FIG. 5 by 90 degrees. That is, as shown in FIG. 9, the metal spring member 13 b has a portion corresponding to the curved portion of the arc toward the width direction of the annular structure 11 and the inner annular structure 12 (direction indicated by the arrow W in FIG. 9). Yes. In the example shown in FIG. 9, the metal spring member 12 is arranged so that the convex portion of the arc faces the outer side in the width direction, but may be arranged so that the concave portion of the arc faces the outer side in the width direction. By arranging the metal spring member 13b in this way, the force transmission efficiency in the circumferential direction (direction indicated by arrow C in FIG. 9) from the inner annular structure 12 to the annular structure 11 is further improved. Further, the metal spring member 13 has high rigidity in the length direction, but low rigidity in the direction in which the portion corresponding to the arc chord is expanded and contracted. For this reason, by using the metal spring member 13, the longitudinal rigidity of the tire / wheel assembly 10 shown in FIG. 1 can be appropriately reduced. Thus, by arranging the metal spring member 13b, the longitudinal rigidity of the tire / wheel assembly 10 shown in FIG. 1 is relatively low, and the force in the circumferential direction between the annular structure 11 and the inner annular structure 12 is reduced. The transmission efficiency can be increased.

  A vehicle travel device 100 shown in FIG. 1 includes an outer rotor type electric motor 20. In the case of the outer rotor type, since the electromagnetic action point is away from the center of rotation, a large rotational moment can be obtained and a large rotational driving torque can be expressed. As a result, the outer rotor type does not require a reduction gear or the like between the electric motor 20 and the drive unit (rubber material layer 14), and can directly drive the drive unit. For this reason, the outer rotor type has no time delay of power transmission, and hardly causes energy loss due to power transmission of a reduction gear or the like, so that the energy transmission efficiency is high. However, since the outer rotor type requires an outer rotor (rotor case 21) having a large outer diameter embedded with permanent magnets, the mass of the motor 20 itself is increased. As a result, in the outer rotor type, so-called unsprung masses such as electric motors, brakes, hubs, wheels, tires and the like increase, and there is a possibility that the grounding stability or the riding comfort may decrease when traveling on an uneven road surface. Since the tire / wheel assembly 10 of the present embodiment has the rubber material layer 14 disposed on the outer side in the radial direction of the annular structure 11, the increase in mass is suppressed, so that the tire / wheel assembly 10 is particularly suitable for an outer rotor type in-wheel motor. Yes.

  In the above example, the force received by the tire / wheel assembly 10 from the road surface was absorbed while the force was transmitted between the annular structure 11 and the inner annular structure 12 by the metal spring members 13, 13a, 13b. However, the force absorbing means is not limited to the metal spring member 13 or the like. For example, an air suspension chamber using a rubber material having a small deformation energy loss may be used.

  FIG. 10 is a side view showing an inner rotor type electric motor. 11 is a cross-sectional view taken along the line BB in FIG. FIG. 12 is a cross-sectional view showing a state where the tire / wheel assembly according to the present embodiment is attached to an inner rotor type electric motor. As shown in FIGS. 10 and 11, in the inner rotor type electric motor 30, the rotor 30 </ b> R is disposed inside the stator 30 </ b> S. The electric motor 30 is used in a so-called in-wheel motor system that is attached to a vehicle suspension. The rotor 30 </ b> R includes a rotor body 34 that is a cylindrical structure, and a permanent magnet 32 that is attached to the outer periphery of the rotor body 34. In the permanent magnet 32, the south pole and the north pole are alternately arranged in the circumferential direction of the rotor body 34. A shaft 35 is attached to the center of the rotor body 34. A rotor bracket 31 is connected to the shaft 35. A tire / wheel assembly 10 shown in FIG. 1 is attached to the outer periphery of the rotor bracket 31.

  The stator 30S is disposed outside the permanent magnet 22 included in the rotor 30R. The stator 30 </ b> S is provided with a plurality of coils 33 on the inner peripheral portion of the stator body 36. The stator body 36 has a bearing 37 at the center. The shaft 35 described above is supported by the stator main body 36 via a bearing 37. With such a structure, the permanent magnet 32 and the rotor main body 34 of the rotor 30R can rotate inside the stator main body 36 around the rotation axis Z. The stator body 36 is fixed to the vehicle.

  As shown in FIG. 12, the vehicle travel device 100 a is configured by combining the tire / wheel assembly 10 and the electric motor 20. Thus, the tire / wheel assembly 10 is attached to the outer side of the rotor bracket 31 of the rotor 30R via the inner annular structure 12. Therefore, when the rotor 30R of the electric motor 30 rotates, the tire / wheel assembly 10 rotates around the rotation axis Z of the electric motor 30 together with the rotor 30R. Thus, in the present embodiment, the tire / wheel assembly 10 can be attached to either an outer rotor type electric motor or an inner rotor type electric motor. Even when the tire / wheel assembly 10 is attached to an inner rotor type electric motor, an effect of radiating the heat generated by the electric motor described above can be obtained.

  As described above, in the tire / wheel assembly according to the present embodiment, the annular structure having the rubber material layer on the outer peripheral portion is connected to the rotor of the electric motor by the metal spring members having a plurality of cross-sectional arc shapes. By doing so, the tire / wheel assembly can effectively dissipate the heat generated by the electric motor into the air, so even if it is an in-wheel motor type vehicle traveling device in which the electric motor heat easily accumulates, It is preferable because it is easy to ensure.

  Further, since the tire / wheel assembly according to the present embodiment uses a thin metal annular structure and a plurality of metal spring members, the overall mass can be kept relatively small. Furthermore, since the tire / wheel assembly according to the present embodiment can reduce the amount of rubber used, hysteresis loss can be suppressed and rolling resistance can be reduced. In addition, since the tire / wheel assembly according to the present embodiment uses a metal material in which energy loss due to deformation is almost zero for portions other than the portion in contact with the ground, the rolling resistance of the tire can be minimized. . As a result, fuel consumption can be reduced.

  Since the outer rotor type electric motor has a larger distance from the central axis to the electromagnetic action point than the inner rotor type electric motor, a larger torque can be obtained with the same electric power. For this reason, the outer rotor type is preferable for the electric motor used for the in-wheel motor type vehicle travel device. However, in the outer rotor system, the outer diameters of the rotor and the stator are increased, so that the mass tends to be increased. In the tire / wheel assembly of the present embodiment, the annular structure, the metal spring member, and the inner annular structure can be made of a relatively thin metal material, so that the overall weight can be reduced. For this reason, even when an outer rotor type electric motor is used for an in-wheel motor type vehicle travel device, an increase in unsprung mass can be suppressed.

  As described above, the tire / wheel assembly according to the present invention is useful for a vehicle employing an in-wheel motor system.

DESCRIPTION OF SYMBOLS 10 Tire / wheel assembly 11 Annular structure 12 Inner annular structure 13, 13a Metal spring member 13TA, 13TB End part 14 Rubber material layer 15 Porous resin 20, 30 Motor 20R, 30R Rotor 20S, 30S Stator 21 Rotor case 22 , 32 Permanent magnets 23, 33 Coils 24, 36 Stator main body 25, 35 Shaft 26, 37 Bearing 31 Rotor bracket 34 Rotor main body 100, 100a Vehicle traveling device

Claims (4)

A cylindrical annular structure;
A porous resin material layer provided on the outer periphery of the annular structure toward the circumferential direction of the annular structure;
A rubber material layer provided on an outer peripheral portion of the porous material layer in a circumferential direction of the annular structure;
A plurality of curved metal spring members provided between the annular structure and an electric motor disposed inside the annular structure, and transmitting rotation of a rotor of the electric motor to the annular structure;
A tire / wheel assembly comprising: A cylindrical structure, having an inner annular structure disposed inside the annular structure and connecting the plurality of metal spring members;
The tire / wheel assembly of claim 1, wherein the inner annular structure is coupled to the rotor.   The tire / wheel assembly according to claim 1 or 2, wherein a material of the annular structure is stainless steel or steel having a thickness of 0.2 mm or greater and 1.0 mm or less.   3. The tire / wheel assembly according to claim 1, wherein a material of the annular structure is stainless steel, steel, aluminum, or aluminum alloy having a thickness greater than 1.0 mm and equal to or less than 5.0 mm.

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