Elastic wheel and mounting structure for elastic wheel

Abstract

The present invention relates to elastic wheels and mounting structures for elastic wheels, and more particularly, aims to provide elastic wheels and mounting structures for elastic wheels that can achieve both the assurance of vibration absorption performance in the vertical direction of the vehicle and the improvement of the vehicle's handling stability. [Solution] The elastic wheel 110 comprises a wheel 120, a first elastic means 123, and a second elastic means 130. A bolt B is inserted through the inner cylinder 125 of the first elastic means 123. The wheel 120 is elastically supported by the hub 102 via the bolt B and the first elastic means 123. The second elastic means 130 elastically supports the wheel 120 relative to the hub 102 in the axle direction. This ensures both vibration absorption performance in the vertical direction of the vehicle and improved handling stability of the vehicle 100. In the mounting structure of the elastic wheel 110, the second elastic means 130 is compressed in the axle direction by the wheel 120 and the hub 102 when mounted.

Description

Technical Field

[0001] The present invention relates to an elastic wheel and an attachment structure of the elastic wheel, and more particularly, to an elastic wheel and an attachment structure of the elastic wheel that can achieve both ensuring vibration absorption performance in the vehicle up-and-down direction and improving the vehicle handling stability.

Background Art

[0002] Conventional elastic wheels that elastically support a wheel with respect to a hub coupled to an axle are known. This type of conventional elastic wheel will be described with reference to FIG. 6. FIG. 6 is a partial cross-sectional view of a vehicle 900 including a conventional elastic wheel 910. As shown in FIG. 6, a hub 902 is coupled to an axle 901 of the vehicle 900. A wheel 903 is attached to the hub 902 by a plurality of bolts B arranged at equal intervals in the circumferential direction. The wheel 903 includes an annular tire 904 formed of an elastic body that contacts the road surface, a cylindrical rim 905 to which the tire 904 is attached to the outer peripheral surface, and an elastic wheel 910 attached to the rim 905.

[0003] The elastic wheel 910 includes a wheel 920 joined to the rim 905. A plurality of through holes 922 arranged in the circumferential direction are formed in the wheel 920. An elastic bush 923 is attached to each of the plurality of through holes 922.

[0004] The elastic bush 923 includes a cylindrical outer cylinder 924 fitted into the through hole 922, a cylindrical inner cylinder 925 disposed on the inner peripheral side of the outer cylinder 924, and a bush elastic body 926 composed of an elastic body connecting the inner cylinder 925 and the outer cylinder 924. By inserting a bolt B protruding from the hub 902 into the inner peripheral side of the inner cylinder 925 of the elastic bush 923 and fastening it with a nut N, the elastic wheel 910 is elastically supported by the hub 902. In this state, the end of the inner cylinder 925 on the hub 902 side abuts against the side surface of the hub 902 on the side where the bolt B protrudes.

[0005] When the vehicle 900 is steered while in motion, the hub 902 rotates due to a steering mechanism (not shown). This changes the steering angle of the wheel 903.

[0006] With such an elastic wheel 910, when the vehicle 900 travels on an uneven road surface, the elastic bush 923 absorbs the vertical vibrations of the vehicle that are transmitted from the tire 904 to the hub 902. [Overview of the project] [Problems that the invention aims to solve]

[0007] However, in the conventional technology described above, the wheel 920 is supported only by the elastic bush 923 via bolt B to the hub 902. Therefore, reducing the modulus of elasticity of the elastic bush 923 improves the vibration absorption performance in the vertical direction of the vehicle, but it becomes difficult to suppress the tilting (twisting) behavior of the wheel 920 relative to the hub 902 during driving. This reduces the handling stability of the vehicle 900. Conversely, increasing the modulus of elasticity of the elastic bush 923 can suppress the tilting behavior of the wheel 920 relative to the hub 902, but it is not possible to sufficiently absorb vibrations in the vertical direction of the vehicle.

[0008] In other words, the conventional technology described above had the problem of not being able to achieve both the assurance of vibration absorption performance in the vertical direction of the vehicle and the improvement of the vehicle's handling stability.

[0009] This invention was made to solve the above-mentioned problems, and aims to provide an elastic wheel that can achieve both the assurance of vibration absorption performance in the vertical direction of the vehicle and the improvement of the vehicle's handling stability. [Means for solving the problem]

[0010] To achieve this objective, the present invention provides an elastic wheel comprising: a wheel having a plurality of through holes arranged in the circumferential direction; and a first elastic means attached to the through holes of the wheel and fixed by bolts to a hub coupled to an axle, wherein the first elastic means comprises a cylindrical outer cylinder fitted into the through holes, a cylindrical inner cylinder disposed on the inner circumference side of the outer cylinder, and a first elastic member composed of an elastic body connecting the inner cylinder and the outer cylinder, and further comprises a second elastic means having a second elastic member composed of an elastic body, wherein the second elastic means is interposed between the side surface of the hub in the axle direction and the opposing surface of the wheel facing that side surface when the wheel is attached to the hub.

[0011] The mounting structure for the elastic wheel of the present invention is such that the elastic wheel is mounted on the hub, and the second elastic means is compressed in the axial direction by the wheel and the hub in the mounted state. [Effects of the Invention]

[0012] The elastic wheel according to claim 1 includes a second elastic means having a second elastic member made of an elastic material, and the second elastic means is interposed between the side surface of the hub in the axle direction and the opposing surface of the wheel facing that side surface when the wheel is mounted on the hub, so that the second elastic member of the second elastic means is compressed between the hub and the wheel. Therefore, it is easier to suppress the behavior of the wheel to tilt (twist) relative to the hub. This improves the handling stability of the vehicle.

[0013] On the other hand, when the wheel moves in a direction perpendicular to the axle direction relative to the hub, the deformation direction of the second elastic means can be set to the shear direction, making it difficult to apply a force that hinders the vertical movement of the wheel relative to the hub. This ensures vibration absorption performance in the vertical direction of the vehicle.

[0014] As a result, it is possible to achieve both the assurance of vibration absorption performance in the vertical direction of the vehicle and the improvement of the vehicle's handling stability.

[0015] According to the elastic wheel of claim 2, in addition to the effects of the elastic wheel of claim 1, the second elastic means comprises one or a plurality of regulating members arranged at a predetermined distance apart in the axial direction from the second elastic member and made of a material with a higher modulus of elasticity than the second elastic member, thereby increasing the apparent modulus of elasticity of the second elastic means compressed by the hub and the wheel. As a result, it is easier to suppress the behavior of the wheel to tilt (twist) relative to the hub. These results can be used to further improve the handling stability of the vehicle.

[0016] Furthermore, since the regulating member has a constant thickness in the axle direction, when the wheel moves in a direction perpendicular to the axle direction relative to the hub, the shear deformation of the second elastic means (first elastic member) makes it difficult to create a portion that compresses the first elastic member in the vertical direction of the vehicle. As a result, it is difficult to apply a force that hinders the vertical movement of the wheel relative to the hub of the vehicle. Thus, vibration absorption performance in the vertical direction of the vehicle can be ensured.

[0017] According to the elastic wheel described in claim 3, in addition to the effects of the elastic wheel described in claim 1, the second elastic means comprises a first region which is a predetermined region radially outward, and a second region which is a region radially inward from the first region, and the axial thickness of the second elastic means differs between the first and second regions. Therefore, the axial thickness of the first and second regions of the second elastic means can be set according to the desired deformation behavior of the wheel relative to the hub and the vibration absorption performance in the vertical direction of the vehicle. This improves the design freedom of the elastic wheel.

[0018] According to the elastic wheel described in claim 4, in addition to the effects of the elastic wheel described in claim 3, the axial thickness of the second elastic means is set such that the first region is thicker than the second region. Therefore, the overall volume of the second elastic means can be reduced compared to the case where the axial thickness of the second elastic means is the same as that of the first region and constant in the radial direction. As a result, it becomes more difficult to apply a force that hinders the vertical movement of the wheel relative to the hub of the vehicle. This makes it easier to ensure vibration absorption performance in the vertical direction of the vehicle.

[0019] Furthermore, since the axial thickness of the second elastic means is set such that the first region is thicker than the second region, it is easier to ensure sufficient compression in the second region when the wheel attempts to tilt (twist) relative to the hub. Therefore, it is easier to suppress the wheel's tendency to tilt (twist) relative to the hub. This ensures the vehicle's handling stability.

[0020] According to the elastic wheel described in claim 5, in addition to the effects of the elastic wheel described in claim 3, the axial thickness of the second elastic means is set such that the first region is thinner than the second region. This makes it easier to ensure the thickness of the thinnest part of the second elastic means compared to the case where the volume of the second elastic means is the same and the axial thickness of the second elastic means is set so that the first region is thicker than the second region. As a result, it is difficult to separate both sides of the second elastic means from the sides of the hub and wheel during relative movement between the wheel and the hub in the axial direction. Therefore, it is difficult to generate abnormal noise caused by the second elastic means contacting or separating from the hub and wheel.

[0021] The elastic wheel according to claim 6 provides, in addition to the effects of the elastic wheel according to claim 1, the second elastic means comprises a first elastic body made of an elastic material and a second elastic body arranged on the outer circumference of the first elastic body and made of an annular elastic material. Since the elastic modulus of the first elastic body and the elastic modulus of the second elastic body are different, it is easier to ensure the axial thickness of the second elastic means compared to the case where the second elastic means comprises a first region and a second region and the axial thickness of the second elastic means differs between the first and second regions. This makes it difficult for both sides of the second elastic means to separate from the sides of the hub and wheel during relative movement between the wheel and hub in the axial direction. Therefore, it is difficult to generate abnormal noise caused by the second elastic means contacting or separating from the hub and wheel.

[0022] According to the elastic wheel described in claim 7, in addition to the effects of the elastic wheel described in claim 1, the second elastic means comprises a plurality of elastic bodies with different elastic moduli that are stacked in the axial direction. As the amount of deformation of the wheel in the axial direction relative to the hub increases, the apparent elastic moduli of the second elastic means can be increased. This makes it possible to ensure vibration absorption performance in the vertical and horizontal directions of the vehicle during the initial behavior when the wheel tries to tilt (twist) relative to the hub, while also making it easier to suppress the behavior in which the wheel tries to tilt (twist) relative to the hub after the initial behavior. As a result, the ride comfort of the vehicle can be improved.

[0023] According to the mounting structure for the elastic wheel described in claim 8, the second elastic means is compressed in the axial direction by the wheel and the hub when mounted. Therefore, the second elastic means that is further compressed by the wheel's tendency to tilt (twist) relative to the hub can reduce the range in which it behaves with a small apparent modulus of elasticity by the amount it is compressed when mounted. This makes it easier to reach the range in which the second elastic means behaves with a large apparent modulus of elasticity more quickly. Thus, it is easier to suppress the wheel's tendency to tilt (twist) relative to the hub. As a result, the steering stability of the vehicle can be improved compared to the case in which the second elastic means is not compressed in the axial direction when mounted.

[0024] In the mounting structure for the elastic wheel, the elastic wheel described in any of claims 1 to 7 is attached to the hub, so the second elastic means is interposed between the side surface of the hub in the axle direction and the opposing surface of the wheel facing that side surface when the wheel is mounted on the hub. Therefore, when the wheel moves in a direction perpendicular to the axle direction with respect to the hub, it is difficult to apply a force that hinders the vertical movement of the wheel relative to the hub. This ensures vibration absorption performance in the vertical direction of the vehicle.

[0025] As a result, it is possible to achieve both the assurance of vibration absorption performance in the vertical direction of the vehicle and the improvement of the vehicle's handling stability. [Brief explanation of the drawing]

[0026] [Figure 1] It is a partial cross-sectional view of a vehicle equipped with an elastic wheel in the first embodiment of the present invention. [Figure 2] It is a partial exploded view of a vehicle with the elastic wheel and the hub disassembled. [Figure 3] (a) is a left side view of the second elastic means, and (b) is a cross-sectional view of the second elastic means taken along line IIIb-IIIb in FIG. 3(a). [Figure 4] (a) is a cross-sectional view of the second elastic means in the second embodiment, and (b) is a cross-sectional view of the second elastic means in the third embodiment. [Figure 5] (a) is a partial cross-sectional view of a vehicle equipped with an elastic wheel in the fourth embodiment, and (b) is a partial cross-sectional view of a vehicle equipped with an elastic wheel in the fifth embodiment. [Figure 6] It is a partial cross-sectional view of a conventional vehicle equipped with an elastic wheel.

Embodiments for Carrying Out the Invention

[0027] Hereinafter, preferred embodiments of the present invention will be described with reference to the accompanying drawings. First, referring to FIG. 1, the elastic wheel 110 in the first embodiment of the present invention will be described. FIG. 1 is a partial cross-sectional view of a vehicle 100 equipped with an elastic wheel 110 in the first embodiment of the present invention. FIG. 1 is a cross-section of the left front wheel (wheel 103) portion of the vehicle 100, including the axis O1 of the vehicle axle 101 of the vehicle 100, and corresponds to a cross-section in a plane perpendicular to the front-rear direction of the wheel 103. Since the right front wheel portion of the vehicle 100 has the same configuration as the left front wheel portion, its description will be omitted.

[0028] In addition, the arrows F-B, L-R, U-D in FIG. 1 respectively indicate the front-rear direction, left-right direction, and up-down direction (vehicle up-down direction) of the vehicle 100. Also, the vehicle 100 is schematically illustrated, and parts other than the vehicle axle 101, the hub 102, and the wheel 103 (for example, a drive device, a suspension device, a vehicle body, a constant velocity joint, a drive shaft, etc.) are omitted in the illustration.

[0029] Here, the mounted state is defined as the state in which the tire 104 is in contact with the road surface and the elastic wheel 110 of the vehicle 100 is attached to the hub 102 (the same applies to the elastic wheels 210, 310, 410, and 510 in the second to fifth embodiments). For the sake of explanation, in the mounted state, the axis O1 of the axle 101 of the vehicle 100 is assumed to extend in the left-right direction of the vehicle 100.

[0030] In this embodiment, a vehicle 100 driven by a front-wheel-drive (FF) system will be described. As shown in Figure 1, the vehicle 100 includes an axle 101 that is rotatable by a drive unit, a hub 102 joined to the axle 101, and a wheel 103 that is both a steering wheel and a drive wheel attached to the hub 102. The axle 101 is connected to the drive shaft by a constant velocity joint. The axis of the hub 102 coincides with the axis O1 of the axle 101 when the hub 102 is joined to the axle 101.

[0031] The wheel 103 comprises an elastic wheel 110, a cylindrical rim 105 connected to the elastic wheel 110, and an elastic tire 104 attached to the rim 105. In this embodiment, the elastic wheel 110 and the rim 105 of the wheel 103 are separate components.

[0032] The hub 102 has multiple bolts B that protrude from one side (left side) of the hub 102 in the axial direction (left-right direction) from which the axis O1 of the axle 101 extends. The multiple bolts B are arranged at equal intervals in the circumferential direction around the axis of the hub 102 (see Figure 2). An elastic wheel 110 is attached to the hub 102, elastically supported by the multiple bolts B of the hub 102.

[0033] The elastic wheel 110 receives rotational force transmitted from the axle 101 via the hub 102 and several bolts B. When the vehicle 100 is steered, the elastic wheel 110 rotates in the same direction as the axle 101 and hub 102 as the axle 101 and hub 102 rotate.

[0034] The mounting structure of the elastic wheel 110 will be described with reference to Figures 2 and 3. Figure 2 is a partially exploded view of the vehicle 100 with the elastic wheel 110 and hub 102 separated. Figure 3(a) is a left side view of the second elastic means 130, and Figure 3(b) is a cross-sectional view of the second elastic means 130 along the line IIIb-IIIb in Figure 3(a). Note that in Figure 2, parts of the vehicle 100 other than the elastic wheel 110 and hub 102 are omitted, and parts of the wheel 120 other than the radial central portion are omitted.

[0035] As shown in Figure 2, the elastic wheel 110 comprises a disc-shaped wheel 120 positioned outward (left side) from the hub 102 in the axle direction, a first elastic means 123 (corresponding to the elastic bush 923 in the prior art) disposed on the wheel 120 and fixed to the hub 102 which is coupled to the axle 101 by a plurality of bolts B, and a disc-shaped second elastic means 130 positioned on the opposing surface 120a of the wheel 120 on the hub 102 side. In the mounted state, the axes of the hub 102, the wheel 120, and the second elastic means 130 coincide with the axis O1 of the axle 101.

[0036] The wheel 120 includes a central hole 121 that penetrates the center of the wheel 120 in the thickness direction, and a plurality of through holes 122 (four in this embodiment) that are arranged at equal intervals in the circumferential direction of a circle centered on the axis of the wheel 120 and penetrate in the thickness direction. The first elastic means 123 is attached to each of the through holes 122.

[0037] The first elastic means 123 comprises a cylindrical outer cylinder 124 fitted into the through hole 122, a cylindrical inner cylinder 125 positioned inside the outer cylinder 124, and a first elastic member 126 made of an elastic body connecting the outer cylinder 124 and the inner cylinder 125. A bolt B is inserted through the inside of the inner cylinder 125 of the first elastic means 123. The bolt B and nut N are fastened together. In the installed state, the end of the inner cylinder 125 on the hub 102 side is in contact with the side surface 102a of the hub 102.

[0038] The second elastic means 130, when mounted, is sandwiched between the side surface 102a of the hub 102 and the opposing surface 120a of the wheel 120 that faces the side surface 102a, and is a member for elastically supporting the wheel 120 in the axle direction relative to the hub 102.

[0039] As shown in Figure 3(a), the second elastic means 130 includes a central hole 131 that penetrates the central portion of the second elastic means 130 in the thickness direction, and a plurality of through holes 132 (four in this embodiment) that are arranged at equal intervals in the circumferential direction around the axis of the second elastic means 130 and penetrate in the thickness direction. In this embodiment, the thickness T2 of the second elastic means 130 is constant in the radial direction. When the second elastic means 130 is installed, a plurality of bolts B are inserted through each of the through holes 132.

[0040] In its installed state, the second elastic means 130 is interposed between the hub 102 and the wheel 120 with its plate thickness direction aligned in the axle axis direction (left-right direction). At this time, the outer circumferential surface of the protruding portion 102b that protrudes from the side surface 102a of the hub 102 is positioned inside the inner circumferential surface of the central hole 131 of the second elastic means 130. This ensures the radial positioning of the second elastic means 130 relative to the hub 102.

[0041] When the vehicle 100 is steered, the hub 102 rotates, causing the hub 102 to tilt relative to the wheel 120, with one side of the hub 102 in the front-rear direction approaching the wheel 120 and the other side moving away from the wheel 120. At this time, on one side of the hub 102 in the front-rear direction, the second elastic means 130 sandwiched between the hub 102 and the wheel 120 is compressed, and on the other side in the front-rear direction, the second elastic means 130 sandwiched between the hub 102 and the wheel 120 is stretched.

[0042] As a result, the apparent modulus of elasticity of the compressed second elastic means 130 increases, allowing the pivoting motion of the hub 102 to be transmitted to the wheel 120. Therefore, in addition to the first elastic means 123 transmitting the pivoting motion of the hub 102 to the wheel 120, the pivoting motion of the hub 102 is also transmitted to the wheel 120 via the second elastic means 130. As a result, the responsiveness of the wheel 120 to the pivoting motion of the hub 102 can be improved compared to a conventional elastic wheel 910 without the second elastic means 130. Thus, the handling stability of the vehicle 100 can be improved.

[0043] Here, when the vehicle 100 is driving, vibrations may be input to the wheels 103 (tires 104) from uneven road surfaces, or centrifugal force may act on the wheels 103 when the vehicle 100 is turning. Due to these vibrations and centrifugal forces, the outer cylinder 124 of the first elastic means 123 may twist relative to the inner cylinder 125. In other words, twisting of the wheel 120 relative to the hub 102 may occur. In this state, the wheel 120 tilts in the camber direction or toe direction relative to the hub 102, or a combination thereof, so the relative position of the wheel 120 with respect to the hub 102 is unstable, and steering stability decreases.

[0044] In contrast, in this embodiment, the elastic wheel 110 has a second elastic means 130 interposed between the side surface 102a of the hub 102 and the opposing surface 120a of the wheel 120. Therefore, when the wheel 120 is about to twist relative to the hub 102, the second elastic means 130 is compressed. This suppresses the twisting of the wheel 120 relative to the hub 102. Thus, the relative position of the wheel 120 with respect to the hub 102 can be stabilized. As a result, steering stability can be improved.

[0045] Since the wheel 120 has an opposing surface 120a on the hub 102 side that is perpendicular to the axle direction, the second elastic means 130 undergoes shear deformation rather than compressive deformation in the vertical direction of the vehicle in response to vibrations in the vertical direction of the vehicle. Generally, objects that undergo elastic deformation have a larger amount of deformation in the shear direction than in the compression direction, so the amount of shear deformation in the vertical direction of the vehicle is greater for the second elastic means 130 compared to the compressive deformation in the axle direction. Therefore, it is less likely to impede the vibration absorption performance in the vertical direction of the vehicle. As a result, even if the second elastic means 130 is provided between the hub 102 and the wheel 120, it is easier to ensure vibration absorption performance in the vertical direction of the vehicle while improving the handling stability of the vehicle 100.

[0046] As shown in Figures 3(a) and 3(b), the second elastic means 130 is composed of a second elastic member 133, which is an elastic body that forms the external shape of the second elastic means 130 described above, and a plurality of disc-shaped restricting members 134 (two in this embodiment) that are stacked inside the second elastic member 133 at a predetermined distance apart in the thickness direction of the second elastic means 130. The restricting members 134 have an external shape along the outer circumferential surface of the second elastic member 133 and an internal shape along the inner surfaces of the central hole 131 and the plurality of through holes 132. The restricting members 134 are made of metal and have an elastic modulus greater than that of the second elastic member 133. The restricting members 134 have a constant thickness in the direction perpendicular to the thickness direction of the second elastic means 130.

[0047] When the vehicle 100 is steered, the rotational movement of the hub 102 compresses the second elastic means 130 by the hub 102 and the wheel 120, causing the second elastic member 133 sandwiched between the regulating member 134 located on the wheel 120 side and the opposing surface 120a of the wheel 120, the second elastic member 133 sandwiched between the regulating member 134 on the wheel 120 side and the regulating member 134 on the hub 102 side, and the second elastic member 133 sandwiched between the regulating member 134 located on the hub 102 side and the side surface 102a of the hub 102 to be compressed.

[0048] As a result, compared to the case where the second elastic means 130 does not have a restricting member 134, the movement of the second elastic member 133 in the thickness direction of the second elastic means 130 can be restricted, and the amount of movement required to increase the apparent elastic modulus of the entire second elastic means 130 can be reduced. In other words, when the wheel 120 moves in the axle direction, the apparent elastic modulus of the entire second elastic means 130 can be increased with a small amount of movement. Therefore, the responsiveness of the wheel 120 to the pivoting motion of the hub 102 can be improved. In addition, the twisting behavior of the wheel 120 relative to the hub 102 can be suppressed. As a result, the handling stability of the vehicle 100 can be improved.

[0049] Here, we consider the case where the overall elastic modulus of the second elastic means 130 is increased in order to improve the steering stability of the vehicle 100. In this case, the responsiveness of the wheel 120 to the turning motion of the hub 102 can be improved, but the elastic modulus of the second elastic means 130 in the shear direction will also increase, making it more difficult for the second elastic means 130 to deform in the shear direction. This may worsen the vibration absorption performance in the vertical direction of the vehicle.

[0050] In contrast, the elastic wheel 110 of this embodiment has a plate-shaped restricting member 134 that is laminated at a predetermined distance apart in the thickness direction of the second elastic means 130, thereby increasing the apparent elastic modulus of the second elastic means 130. As a result, the elastic modulus of the second elastic means 130 in the shear direction does not tend to increase. Therefore, it is easier to ensure the amount of deformation of the second elastic means 130 in the shear direction, and as a result, it is possible to improve the steering stability of the vehicle 100 while ensuring vibration absorption performance in the vertical direction of the vehicle.

[0051] Furthermore, since the regulating member 134 has a constant thickness in the direction perpendicular to the thickness direction of the second elastic means 130, when installed, the sides of the regulating member 134 are planes perpendicular to the axle axis direction. This makes it difficult to compress and deform the second elastic member 133 in the shear direction (vertical direction of the vehicle) when the wheel 120 moves relative to the second elastic means 130. Thus, it is difficult to apply a force that hinders the vertical movement of the wheel 120 relative to the hub 102. As a result, it is easier to ensure vibration absorption performance in the vertical direction of the vehicle.

[0052] In the mounted state, the second elastic means 130 is clamped between the side surface 102a of the hub 102 and the opposing surface 120a of the wheel 120 in a state of compression in the axle direction (pre-compressed state). In the pre-compressed state, the second elastic means 130 is pre-compressed by a value obtained by subtracting the plate thickness T1 after pre-compression from the plate thickness T2 of the second elastic means 130 before pre-compression (T2-T1).

[0053] This reduces the initial range dominated by soft deformation within the range of compression deformation of the second elastic means 130 when the wheel 120 approaches the hub 102 in the axial direction and the second elastic means 130 is compressed in the axial direction. As a result, the responsiveness of the wheel 120 to the pivoting motion of the hub 102 can be improved, and twisting of the wheel 120 relative to the hub 102 can be suppressed.

[0054] Furthermore, when the wheel 120 is separated from the hub 102 in the axle direction, the second elastic means 130 can be compressed within the range in which it has been pre-compressed. Therefore, compared to when the second elastic means 130 is not compressed, the responsiveness of the wheel 120 to the pivoting motion of the hub 102 can be improved, and twisting of the wheel 120 relative to the hub 102 can be suppressed.

[0055] These results indicate that, in the mounted state, compressing and clamping (pre-compressing) the second elastic means 130 in the axle direction improves the steering stability of the vehicle 100 when the wheel 120 approaches the hub 102 in the axle direction or when the wheel 120 moves away from the hub 102 in the axle direction.

[0056] Next, with reference to Figure 4(a), the elastic wheel 210 in the second embodiment will be described. In the first embodiment, the case in which the plate thickness T2 of the second elastic means 130 is set to be constant in the radial direction was described. In contrast, in the second embodiment, the case in which the plate thickness of the first region A1, which is a predetermined region radially outside the second elastic means 230, is set to be thicker than the plate thickness of the second region A2, which is a region radially inside the first region A1, will be described. Figure 4(a) is a cross-sectional view of the second elastic means 230 in the second embodiment. Note that parts identical to those in the first embodiment are denoted by the same reference numerals and their descriptions are omitted (the same applies to the third to fifth embodiments).

[0057] As shown in Figure 4(a), unlike the second elastic means 130 in the first embodiment, the second elastic means 230 does not have a central hole 131 and a regulating member 134, and is composed of a second elastic member 133 (similarly in the second elastic means 330, 430, and 530 of the third to fifth embodiments). The radial positioning of the second elastic means 230 relative to the hub 102 is achieved by fitting a projection (not shown) on the side surface 102a of the hub 102 into a groove (not shown) provided on the side surface of the second elastic means 230 on the hub 102 side (similarly in the second elastic means 330, 430, and 530 of the third to fifth embodiments).

[0058] The second elastic means 230 has a shape in which the plate thickness T4 is thinnest at the radial center and increases from the radial center toward the outer circumferential surface. In this embodiment, the plate thickness T3 at the outermost radial edge of the second elastic means 230 is set to be the same as the plate thickness T2 of the second elastic means 130 before pre-compression in the first embodiment. The plate thickness T4 of the second elastic means 230 is set to be thicker than the plate thickness T1 when pre-compressed.

[0059] Since the second elastic means 230 of the elastic wheel 210 in the second embodiment has the shape described above, the amount (volume) of the second elastic means 230 that is sandwiched between the hub 102 and the wheel 120 in the mounted state (including pre-compression) can be reduced compared to the second elastic means 130 in the first embodiment. As a result, the apparent elastic modulus in the shear direction of the second elastic means 230 when the wheel 120 moves relative to the hub 102 in the vehicle vertical direction can be reduced. Therefore, it is difficult to apply a force that hinders the movement of the wheel 120 relative to the hub 102 in the vehicle vertical direction. As a result, the vibration absorption performance in the vehicle vertical direction can be improved.

[0060] Here, if the total volume of the second elastic means 230 in the second embodiment is smaller than the total volume of the second elastic means 130 in the first embodiment, which has the same diameter and elastic modulus, then the amount by which the second elastic means 230 is compressed by being squeezed between the hub 102 and the wheel 120 in response to the pivoting motion of the hub 102 will be reduced, making it difficult for the pivoting motion of the hub 102 to be transmitted to the wheel 120. Furthermore, it will also be difficult to suppress the twisting of the wheel 120 relative to the hub 102.

[0061] In contrast, the plate thickness T3 of the radially outer region of the second elastic means 230, which is the part that mainly transmits the pivoting motion of the hub 102 to the wheel 120, i.e., the outermost edge portion of the first region A1, is the same as the plate thickness T2 of the second elastic means 130 in the first embodiment. This makes it easier to ensure that the amount of compression of the second elastic means 230 (first region A1) by being sandwiched between the hub 102 and the wheel 120 is secured. This makes it easier to transmit the pivoting motion of the hub 102 to the wheel 120. In addition, twisting of the wheel 120 relative to the hub 102 can be suppressed. As a result, it is easier to ensure the steering stability of the vehicle 200.

[0062] Next, with reference to Figure 4(b), the elastic wheel 310 in the third embodiment will be described. In the first embodiment, the case in which the plate thickness T2 of the second elastic means 130 is set to be constant in the radial direction was described. In contrast, in the third embodiment, the case in which the plate thickness of the first region A1, which is a predetermined region on the radially outer side of the second elastic means 330, is set to be thinner than the plate thickness of the second region A2, which is a region radially inner to the first region A1, will be described. Figure 4(b) is a cross-sectional view of the second elastic means 330 in the third embodiment.

[0063] As shown in Figure 4(b), the second elastic means 330 has a shape in which the thickness T6 is thickest at the radial center and decreases towards the outer circumferential surface from the radial center. In this embodiment, the thickness T6 at the radial center of the second elastic means 330 is set to be the same as the thickness T2 of the second elastic means 130 in the first embodiment and the thickness T3 of the second elastic means 230 in the second embodiment. The thinnest thickness T5 is at the radial outermost edge of the second elastic means 330. The thickness T5 of the second elastic means 330 is set to be thicker than the thickness T1 when pre-compressed.

[0064] Since the second elastic means 330 of the elastic wheel 310 in the third embodiment has the shape described above, the overall volume of the second elastic means 330 can be made smaller than that of the second elastic means 130 in the first embodiment when mounted (including pre-compression). As a result, the same effects as in the second embodiment can be achieved.

[0065] In the third embodiment, the elastic wheel 310 has the same volume and the same radial boundary position between the first region A1 and the second region A2. Compared to the elastic wheel 210 in the second embodiment, the thinnest part of the second elastic means 330, specifically the plate thickness T5, can be made larger than the thinnest part of the second elastic means 230, specifically the plate thickness T4. Therefore, it is less likely that any uncompressed portion will occur when the second elastic means 330 is precompressed. This reduces the generation of abnormal noise caused by the second elastic means 330 repeatedly coming into contact with and separating from the hub 102 and the wheel 120 when the vehicle 100 is running.

[0066] Next, with reference to Figure 5(a), the elastic wheel 410 in the fourth embodiment will be described. In the first embodiment, the case in which the second elastic means 130 of the elastic wheel 110 is composed of a single elastic body was described. In contrast, in the fourth embodiment, the case in which the second elastic means 430 of the elastic wheel 410 is composed of multiple elastic bodies (two in this embodiment) stacked in the axle direction will be described. Figure 5(a) is a partial cross-sectional view of a vehicle 400 equipped with the elastic wheel 410 in the fourth embodiment.

[0067] As shown in Figure 5(a), the second elastic means 430 is composed of an outer elastic body 430a, which is an elastic body positioned on the wheel 120 side, and an inner elastic body 430b, which is an elastic body positioned on the hub 102 side. In this embodiment, the plate thickness of the outer elastic body 430a and the plate thickness of the inner elastic body 430b are the same. In the mounted state, the thickness of the outer elastic body 430a and the inner elastic body 430b stacked in the axle direction is T1. In this embodiment, the outer elastic body 430a is composed of an elastic body with a lower modulus of elasticity than the inner elastic body 430b.

[0068] In the fourth embodiment, the elastic wheel 410 has an outer elastic body 430a and an inner elastic body 430b with different elastic moduli stacked in the axial direction. As the wheel 120 approaches the hub 102, in the initial stage, the elastic deformation of the second elastic means 430 is dominated by the elastic deformation of the elastic body with the lower elastic moduli (in this embodiment, the outer elastic body 430a) of the outer elastic body 430a and the inner elastic body 430b. Subsequently, the elastic deformation shifts from being dominated by the elastic deformation of the elastic body with the lower elastic moduli to being dominated by the elastic deformation of the elastic body with the higher elastic moduli (in this embodiment, the inner elastic body 430b) of the outer elastic body 430a and the inner elastic body 430b. That is, the apparent elastic moduli of the second elastic means 430 are low in the initial stage and then shift to becoming higher.

[0069] This makes it easier to absorb vibrations in the vertical and horizontal directions of the vehicle during the initial stages of the hub 102's rotational movement, and then, as the rotational movement of the hub 102 progresses further, it ensures the responsiveness of the wheel 120 to the rotational movement of the hub 102 and suppresses twisting of the wheel 120 relative to the hub 102. Thus, the ride comfort of the vehicle 400 can be improved.

[0070] Next, with reference to Figure 5(b), the elastic wheel 510 in the fifth embodiment will be described. In the first embodiment, the case in which the second elastic means 130 of the elastic wheel 110 is composed of a single elastic body was described. In contrast, in the fifth embodiment, the case in which the second elastic means 530 of the elastic wheel 510 is composed of multiple elastic bodies (two in this embodiment) stacked radially will be described. Figure 5(b) is a partial cross-sectional view of a vehicle 500 equipped with the elastic wheel 510 in the fifth embodiment.

[0071] As shown in Figure 5(b), the second elastic means 530 is composed of a central elastic body 530a, which is an elastic body positioned on its axial side, and an outer elastic body 530b, which is an elastic body positioned on the outer periphery of the central elastic body 530a. In this embodiment, the plate thickness of the central elastic body 530a and the plate thickness of the outer elastic body 530b are the same. The plate thickness of the second elastic means 530 in the installed state is T1. In this embodiment, the outer elastic body 530b is composed of an elastic body with a higher modulus of elasticity than the central elastic body 530a.

[0072] In the fifth embodiment, the elastic wheel 510 has a central elastic body 530a and an outer elastic body 530b with different elastic moduli stacked radially. Therefore, compared to the elastic wheel 110 in the first embodiment, the elastic moduli of a portion of the elastic body in the radial direction (in this embodiment, the outer elastic body 530b) can be made larger than the elastic moduli of the elastic body in the other portion of the elastic body in the radial direction (in this embodiment, the central elastic body 530a).

[0073] This reduces the apparent modulus of elasticity in the shear direction of the second elastic means 430 when the wheel 120 moves relative to the hub 102 in the vertical direction of the vehicle while mounted (including pre-compression). Therefore, it becomes more difficult to apply forces that hinder the vertical movement of the wheel 120 relative to the hub 102. As a result, the vibration absorption performance in the vertical direction of the vehicle can be improved.

[0074] Furthermore, in the fifth embodiment, the elastic wheel 510 has an outer elastic body 530b with a higher modulus of elasticity than the central elastic body 530a. Therefore, when steering the vehicle 500 and when the wheel 120 twists relative to the hub 102, the outer elastic body 530b, which has a higher modulus of elasticity than the central elastic body 530a, is compressed more. This makes it easier to transmit the turning motion of the hub 102 to the wheel 120 and suppresses the twisting of the wheel 120 relative to the hub 102. As a result, it is easier to ensure the handling stability of the vehicle 500.

[0075] In the fifth embodiment, unlike the elastic wheels 210 and 310 in the second and third embodiments, the thickness of the second elastic means 230 and 330 does not need to be reduced, making it easier to ensure sufficient thickness for the second elastic means 530. Therefore, it is less likely that any uncompressed portion will occur when the second elastic means 530 is precompressed. This reduces the generation of abnormal noise caused by the second elastic means 530 repeatedly coming into contact with and separating from the hub 102 and wheel 120 during vehicle 500 operation.

[0076] Although the present invention has been described above based on embodiments, it can be easily inferred that the present invention is not limited in any way to the above embodiments, and that various improvements and modifications are possible without departing from the spirit of the present invention.

[0077] It is naturally possible to combine some or all of the configurations in each of the above embodiments with some or all of the configurations in other embodiments. For example, the second elastic means 230, 330, 430, and 530 in the second to fifth embodiments may also include the regulating member 134 in the first embodiment. In that case, the second elastic means 430 and 530 in the fourth and fifth embodiments may have the regulating member 134 on both of the multiple elastic bodies, or on only one of them.

[0078] In the embodiments described above, the case where the wheel 103 is both a steering wheel and a drive wheel was explained, but the wheel 103 may be a steering wheel and a driven wheel, a non-steering wheel and a drive wheel, or a non-steering wheel and a driven wheel.

[0079] In each of the above embodiments, the second elastic means 130, 230, 330, 430, and 530 may have a fluororesin coating on their sides (the surfaces that come into contact with the opposing surface 120a of the wheel 120 and the side surface 102a of the hub 102) to facilitate sliding against the opposing surface 120a of the wheel 120 and the side surface 102a of the hub 102. The second elastic member 133 may also be a self-lubricating elastic body. For example, a fluororubber can be used as the lubricating elastic body. In any case, the vertical movement of the wheel 120 relative to the hub 102 can be made less likely to be hindered by the second elastic means 130, 230, 330, 430, and 530, thereby improving the steering stability of the vehicle 100 while improving the vibration absorption performance in the vertical direction of the vehicle.

[0080] In the embodiments described above, the case in which the elastic wheel 110 is separate from the rim 105 has been explained, but the elastic wheel 110 may also be molded integrally with the rim 105.

[0081] In the embodiments described above, the case in which the second elastic means 130, 230, 330, 430, and 530 are disc-shaped was explained, but the second elastic means 130, 230, 330, 430, and 530 may also be polygonal or elliptical plates.

[0082] In the embodiments described above, the case in which the second elastic means 130, 230, 330, 430, and 530 contact the wheel 120 only on a plane perpendicular to the axle 101 (the opposing surface 120a of the wheel 120) has been explained. However, it is also possible for them to contact the wheel 120 on a surface intersecting the axle 101. In this case, it is preferable that the second elastic means 130, 230, 330, 430, and 530 are joined (for example, bonded) to the opposing surface 120a of the wheel 120. This makes it easier to allow the second elastic means 130, 230, 330, 430, and 530 to follow the wheel 120 without compressing them in the shear direction. This makes it easier to ensure vibration absorption performance in the vertical direction of the vehicle.

[0083] In the embodiments described above, the case in which the second elastic means 130, 230, 330, 430, and 530 are compressed in the axle direction between the opposing surface 120a of the wheel 120 and the side surface 102a of the hub 102 when mounted has been explained. However, the second elastic means 130, 230, 330, 430, and 530 may not be compressed in the axle direction when mounted. In this case, it is preferable that the second elastic means 130, 230, 330, 430, and 530 are joined (for example, bonded) to the opposing surface 120a of the wheel 120.

[0084] In the embodiments described above, the case in which the restricting member 134 has a constant thickness in the axle direction was explained, but the restricting member 134 may have different thicknesses in the axle direction depending on its position in the radial direction. For example, the central part of the restricting member 134 in the radial direction may be thicker, and the other parts may be thinner than the central part in the radial direction, or vice versa. Also, the area between the central part of the restricting member 134 in the radial direction and the outer edge in the radial direction may be thicker than the other parts, or vice versa.

[0085] In the first embodiment described above, the case in which the regulating member 134 is built inside the second elastic member 133 in the radial direction (its shape in front view is slightly smaller than that of the second elastic member 133) was explained. However, it is also possible for the regulating member 134 to protrude outward from the outer peripheral surface of the second elastic member 133 (its shape in front view is slightly larger than that of the second elastic member 133). Furthermore, there may be three or more regulating members 134, or they may be omitted.

[0086] In the second embodiment described above, the case in which the thickness of the second elastic means 230 decreases as it extends radially outward was explained, but the second elastic means 230 may also be in a stepped shape in which the thickness of the second region A2 is thicker than that of the first region A1.

[0087] In the third embodiment described above, the case in which the thickness of the second elastic means 330 increases as it extends radially outward was explained. However, the second elastic means 330 may also have a stepped shape in which the thickness of the second region A2 is thinner than that of the first region A1.

[0088] In the fourth embodiment described above, the case in which the elastic modulus of the outer elastic body 430a is smaller than that of the inner elastic body 430b was explained, but it is also possible for the elastic modulus of the outer elastic body 430a to be larger than that of the inner elastic body 430b.

[0089] In the fourth embodiment described above, the case in which the second elastic means 430 consists of two elastic bodies (an outer elastic body 430a and an inner elastic body 430b) stacked in the axle-axis direction was explained, but it is also possible for three or more elastic bodies to be stacked in the axle-axis direction.

[0090] In the fifth embodiment described above, the case in which the elastic modulus of the outer elastic body 530b is greater than that of the central elastic body 530a was explained, but it is also possible for the elastic modulus of the outer elastic body 530b to be less than that of the central elastic body 530a.

[0091] In the fifth embodiment described above, the second elastic means 530 was described as being composed of two elastic bodies (a central elastic body 530a and an outer elastic body 530b) stacked radially, but it may also be composed of three or more elastic bodies stacked radially.

[0092] In the fifth embodiment described above, a case was described in which multiple elastic bodies (a central elastic body 530a and an outer elastic body 530b) are arranged in contact in the radial direction, but it is also possible for multiple elastic bodies to be arranged spaced apart in the radial direction. [Explanation of Symbols]

[0093] 101 axles 102 Hub 102a side 110, 210, 310, 410, 510 Elastic Wheels 120 wheels 120a Opposing surface 122 Through hole 123 First Elastic Means 124 Outer cylinder 125 Inner cylinder 126 First Elastic Member 130, 230, 330, 430, 530 Second Elastic Means 133 Second Elastic Member 134 Regulating member 430a Outer elastic body (part of multiple elastic bodies) 430b Inner elastic body (part of multiple elastic bodies) 530a Central elastic body (first elastic body) 530b Outer elastic body (second elastic body) A1 1st area A2 2nd area B bolt T1, T2, T3, T4, T5, T6 Plate thickness (thickness) Arrows L and R indicate left and right directions (axis direction)

Claims

1. The device comprises a wheel having a plurality of through holes arranged in the circumferential direction, and a first elastic means attached to the through holes of the wheel and fixed by bolts to a hub that is coupled to an axle, In an elastic wheel comprising a first elastic means comprising a cylindrical outer cylinder fitted into the through hole, a cylindrical inner cylinder disposed on the inner circumference side of the outer cylinder, and a first elastic member composed of an elastic body connecting the inner cylinder and the outer cylinder, The device comprises a second elastic means having a second elastic member made of an elastic material, The second elastic means is interposed between the side surface of the hub in the axle direction and the opposing surface of the wheel facing that side surface, in a mounting state in which the wheel is attached to the hub.

2. The second elastic means comprises one or a plurality of regulating members arranged at a predetermined distance apart in the axle-axis direction, which are positioned inward from the second elastic member in the axle-axis direction and are made of a material with a greater modulus of elasticity than the second elastic member. The elastic wheel according to claim 1, characterized in that the regulating member has a constant thickness in the axle direction.

3. The second elastic means comprises a first region which is a predetermined region radially outward, and a second region which is a region radially inward from the first region. The elastic wheel according to claim 1, characterized in that the thickness of the second elastic means in the axle axis direction is different in the first region and the second region.

4. The elastic wheel according to claim 3, characterized in that the thickness of the second elastic means in the axle axis direction is set such that the first region is thicker than the second region.

5. The elastic wheel according to claim 3, characterized in that the thickness of the second elastic means in the axle axis direction is set such that the first region is thinner than the second region.

6. The second elastic means comprises a first elastic body made of an elastic material, and a second elastic body disposed on the outer circumference of the first elastic body and made of an annular elastic material. The elastic wheel according to claim 1, characterized in that the elastic modulus of the first elastic body and the elastic modulus of the second elastic body are different.

7. The elastic wheel according to claim 1, characterized in that the second elastic means comprises a plurality of elastic bodies with different elastic moduli that are stacked in the axial direction.

8. An elastic wheel mounting structure for attaching an elastic wheel according to any one of claims 1 to 7 to the hub, The mounting structure for an elastic wheel is characterized in that the second elastic means is compressed in the axial direction by the wheel and the hub in the mounting state.

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