Tire Testing Equipment

Abstract

To provide a tire testing device which easily resists the positional deviation in the rotation direction to a hub of a wheel and prevents the breakage of fastening means that fixes the wheel and the hub.SOLUTION: A tire testing device comprises: a tire support part which has a travel base, a wheel 16 and a hub 13, and supports an evaluation object tire X in a rotatable manner via the wheel 16 and the hub 13; and a plurality of fastening members 17, 18 which fastens the wheel 16 to the hub 13. The wheel 16 has a wheel side uneven part 30a which becomes uneven in the tire axial direction at one or a plurality of positions in the tire circumferential direction on an attachment object surface 16c attached to the hub 13. The hub 13 has a hub side uneven part 30b which becomes uneven in the tire axial direction at one or a plurality of positions in the tire circumferential direction on an attachment object surface 13c attached with the wheel 16. The wheel side uneven part 30a and the hub side uneven part 30b constitute a contact uneven pair 30 which is complementary so as to be in contact with each other in the tire axial direction.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a tire testing apparatus. [Background technology]

[0002] Patent Document 1 discloses a tire testing device for measuring the running performance of a tire to be evaluated. The tire testing device has a running stand with which the tire to be evaluated comes into contact and a tire support unit that supports the tire to be evaluated. The tire support unit rotatably supports a wheel on which the tire to be evaluated is mounted on a rim. Generally, in such testing devices, a hub rotatably attached to one end of a rotating shaft is fitted into a hub hole provided in the radial center of the wheel, and a stud bolt provided in the hub, extending in the direction of the rotation axis and protruding toward the rim, is inserted into a bolt insertion hole provided in the wheel and a nut is screwed onto the hub to fasten the wheel to the wheel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-163978 Summary of the Invention [Problem to be solved by the invention]

[0004] In the tire support structure disclosed in Patent Document 1, if the wheel shifts in the rotational direction relative to the hub during sudden braking, there is a risk that the bolts used as fastening means may be damaged, but there is no disclosure of how to prevent rotational shift of the wheel relative to the hub.

[0005] An object of the present invention is to provide a tire testing apparatus that can easily withstand positional deviation in the rotational direction of the wheel relative to the hub under braking and driving conditions in the tire testing apparatus, and that prevents damage to the fastening means that secures the wheel and hub. [Means for solving the problem]

[0006] One aspect of the present invention is a running platform on which the test tire is brought into contact; a wheel on which the tire to be evaluated is mounted on a rim; a tire support unit having a hub to which the wheel is attached and rotatably supporting the tire to be evaluated via the wheel and the hub; Ta a plurality of fastening members for fastening the wheel to the hub at a plurality of positions in the circumferential direction of the wheel; Equipped with the wheel has a wheel-side uneven portion that extends in the tire radial direction with a predetermined cross-sectional shape that is uneven in the tire axial direction at one or more positions in the tire circumferential direction on a mounting surface that is attached to the hub, the hub has a hub-side uneven portion that extends in the tire radial direction with a predetermined cross-sectional shape that is uneven in the tire axial direction at one or more positions in the tire circumferential direction on the mounting surface to which the wheel is mounted, The tire testing device provides a tire testing device in which the wheel-side concave-convex portion and the hub-side concave-convex portion form a complementary abutting concave-convex pair that abuts against each other in the tire axial direction.

[0007] According to the present invention, the contact area between the hub and the wheel can be increased compared to when no unevenness is provided between the mounting surface of the hub and the mounted surface of the wheel, thereby increasing the frictional force between the hub and the wheel, making it easier to resist misalignment in the rotational direction of the hub and the wheel under braking and driving conditions in a tire testing device, and preventing damage to the bolts that secure them together.

[0008] The abutting concave-convex pair is In the cross-sectional shape, a first inclined side inclined toward one side in the tire circumferential direction and toward one side in the tire axial direction; a second inclined side inclined toward one side in the tire axial direction toward the other side in the tire circumferential direction; may have

[0009] According to this configuration, the first inclined edge and the second inclined edge provide radially extending inclined surfaces on both sides in the circumferential direction, thereby increasing the friction force between the hub and the wheel regardless of the direction of rotation of the tire.

[0010] Furthermore, when the hub and wheel are misaligned in the rotational direction, for example, if the inclined surface formed by the first inclined edge of the hub and the inclined surface formed by the first inclined edge of the wheel move in the tire circumferential direction, a misalignment occurs between the hub and wheel, with one inclined surface climbing up the other inclined surface. In this case, the thickness between the hub and wheel increases by the amount that one inclined surface climbs up the other inclined surface, stretching the bolt by the amount of the increased thickness. At the same time, the elastic force generated increases the axial force. As a result, the hub and wheel tend to misalign in the rotational direction, increasing the axial force and suppressing misalignment between the hub and wheel. This provides the so-called self-locking effect of the Nord-Lock washer.

[0011] In the cross-sectional shape, the first inclined side is inclined at a first inclination angle with respect to a plane perpendicular to the tire axial direction, the second inclined side is inclined at a second inclination angle with respect to a plane perpendicular to the tire axial direction, The first tilt angle and the second tilt angle may be equal to or greater than 5° and equal to or less than 45°.

[0012] This configuration ensures the self-locking effect. If the first and second tilt angles are less than the bolt lead angle, e.g., 5°, the bolt will loosen and the axial tension will not increase. If the first and second tilt angles are greater than 45°, the contact area between the hub-side uneven portion and the wheel-side uneven portion will decrease, making it difficult to increase the friction between the hub and wheel.

[0013] In the cross-sectional shape, the first inclined side is inclined at a first inclination angle with respect to a plane perpendicular to the tire axial direction, the second inclined side is inclined at a second inclination angle with respect to a plane perpendicular to the tire axial direction, The second tilt angle may be set to be larger than the first tilt angle.

[0014] The contact recess-projection pair may extend spirally when viewed from the tire axial direction so that the inner side in the tire radial direction is located on one side of the outer side in the tire rotation direction.

[0015] According to this configuration, the distance from the radially inner side to the radially outer side is increased compared to when the contact concave-convex pair is provided linearly, and therefore the contact area is increased.

[0016] The abutting concave-convex pair is It may be conical in shape with the tire rotation axis as its center.

[0017] With this configuration, the mounting surface of the hub and the mounted surface of the wheel are inclined, which increases the contact area between the hub and the wheel compared to when the mounting surface and the mounted surface are flat, thereby further increasing the frictional force between the hub and the wheel.

[0018] Another aspect of the present invention is a running platform on which the test tire is brought into contact; a wheel on which the tire to be evaluated is mounted on a rim; a tire support unit having a hub to which the wheel is attached and rotatably supporting the tire to be evaluated via the wheel and the hub; a plurality of fastening members for fastening the wheel to the hub at a plurality of positions in the tire circumferential direction; Equipped with the wheel has a wheel-side uneven portion on a mounting surface attached to the hub, the wheel having a predetermined cross-sectional shape that is uneven in the tire axial direction; the hub has a hub-side uneven portion on a mounting surface to which the wheel is mounted, the hub having a predetermined cross-sectional shape that is uneven in the tire axial direction, The wheel-side concave-convex portion and the hub-side concave-convex portion form a mating concave-convex pair that are complementary to each other so as to mate with each other in the tire axial direction.

[0019] According to the present invention, by fitting the hub and wheel in the tire axial direction, it is easy to resist rotational misalignment (shear force) between them in the tire rotation direction. More specifically, the shear force due to rotational misalignment between the hub and wheel in the rotation direction can be applied to the bolts and also borne by the fitting concave-convex pair. Therefore, under braking and driving conditions in a tire testing device, it is easy to resist misalignment in the rotation direction between the two, and damage to the bolts that secure them is prevented.

[0020] The fitting recess-projection pair is preferably located between the plurality of fastening members in the tire circumferential direction.

[0021] According to this configuration, the fitting concave-convex pair can more easily bear the shear force acting on the bolt.

[0022] The fitting concave-convex pair is In the cross-sectional shape, a first inclined side inclined toward one side in the tire circumferential direction and toward one side in the tire axial direction; a second inclined side inclined toward one side in the tire axial direction toward the other side in the tire circumferential direction; may have

[0023] This configuration prevents damage to the bolts that secure the hub and wheel with a simple structure that simply provides complementary mating recesses and protrusions on the hub and wheel. Furthermore, the V-shape formed by the first and second inclined edges guides the wheel during assembly, making it easy to assemble the wheel to the hub.

[0024] The fitting recess-projection pair may have a rectangular cross-sectional shape.

[0025] According to this configuration, the same effects as those described above can be obtained. [Effects of the Invention]

[0026] According to the present invention, it is possible to easily resist positional deviation in the rotational direction of the wheel relative to the hub under braking and driving conditions in a tire testing device, and damage to the fastening means that secures the wheel and hub can be prevented. [Brief explanation of the drawings]

[0027] [Figure 1] 1 is a schematic view of a tire testing device according to a first embodiment of the present invention. [Figure 2] 2 is a schematic diagram of the tire testing device of FIG. 1 viewed from the tire axial direction. [Figure 3] FIG. 3 is an enlarged cross-sectional view of a main part taken along line III-III in FIG. [Figure 4] FIG. 4 is an enlarged view of a main part as seen from the direction of arrow IV in FIG. 3. [Figure 5] FIG. 5 is a developed cross-sectional view taken along line VV in FIG. 4. [Figure 6] FIG. 5 is a developed cross-sectional view taken along line VV in FIG. 4 according to a first modified example. [Figure 7] FIG. 5 is a developed cross-sectional view taken along line VV in FIG. 4 according to a second modified example. [Figure 8] 4 is an enlarged view of a main part according to a third modified example, as viewed in the direction of arrow IV in FIG. 3. FIG. [Figure 9] FIG. 11 is an enlarged cross-sectional view of a main part taken along line III-III in FIG. 1 according to a fourth modified example. [Figure 10] FIG. 10 is an enlarged view of a main part of a tire testing device according to a second embodiment, as viewed from the tire axial direction. [Figure 11] FIG. 11 is a developed cross-sectional view taken along line XI-XI in FIG. [Figure 12] FIG. 11 is a developed cross-sectional view taken along line XI-XI in FIG. 10 according to a fifth modified example. [Figure 13] FIG. 11 is an enlarged view of a main part of a tire testing device according to a third embodiment, as viewed from the tire axial direction. [Figure 14] FIG. 14 is an enlarged cross-sectional view of a main part taken along line XIV-XIV in FIG. [Figure 15] FIG. 14 is an enlarged view of a main part in FIG. 13 according to another modified example. [Figure 16]FIG. 5 is a developed cross-sectional view taken along line VV in FIG. 4 according to another modified example. DETAILED DESCRIPTION OF THE INVENTION

[0028] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Note that the following description is essentially merely exemplary and is not intended to limit the present invention, its applications, or its uses. The drawings are schematic, and the ratios of dimensions, etc., differ from those of the actual objects.

[0029] [First embodiment] 1 and 2 show a schematic configuration of a tire testing apparatus 1 according to a first embodiment of the present invention. As shown in Fig. 1 and 2, the tire testing apparatus 1 has a rolling unit 10 that rolls a tire X to be evaluated under predetermined conditions, and a control unit (not shown) that controls the operation of the rolling unit 10.

[0030] As shown in FIG. 1, the rolling unit 10 includes a running platform 11, a wheel 16 having a rim around the outer periphery of the tire X to be evaluated, a tire support unit 12 having a hub 13 to which the wheel 16 is attached and rotatably supporting the tire X to be evaluated via the wheel 16 and the hub 13, and a plurality of fastening members 17, 18 that fasten the wheel 16 to the hub 13 at a plurality of positions in the tire circumferential direction.

[0031] The running platform 11 has a strip-shaped endless body 11a wound between a pair of rollers 14, and the tire X to be evaluated rolls on the outer surface of the endless body 11a. The endless body 11a rotates between the pair of rollers 14 by driving at least one of the pair of rollers 14. The tire X to be evaluated is given a driving force from the rotating endless body 11a and rotates together with the endless body 11a, thereby rolling on the running platform 11 at a desired moving speed V (relative speed with respect to the endless body 11a).

[0032] 2 and 3, the tire support part 12 rotatably supports the tire X to be evaluated via the tire rotation shaft 12a. More specifically, a hub 13 rotatably attached to one end of the rotation shaft 12a is fitted into a hub hole 16a provided in the radial center of the wheel 16, and a hub bolt 17 provided in the hub 13 extends in the direction of the rotation shaft 12a and protrudes outward from the vehicle body, and is inserted into a bolt insertion hole 16b provided in the wheel 16 and a nut 18 is screwed onto the hub 13, thereby fastening the wheel 16 to the hub 13.

[0033] A spigot-fit structure is adopted for the hub 13 and the wheel 16 to facilitate their mutual alignment. The spigot-fit structure is provided with a structure in which the outer peripheral surface of a cylindrical protrusion 13a that protrudes from the outer side of the hub 13 toward the outer side of the vehicle body coaxially with the hub 13 abuts against the inner peripheral surface of a hub hole 16a formed in the center of the wheel 16.

[0034] Fig. 4 is a view of the mounting surface 16c mounted on the hub of the wheel 16 as seen from the tire axial direction (the direction of arrow IV in Fig. 3). As shown in Fig. 5, the mounting surface 16c is provided with wheel-side uneven portions 30a that are uneven in the tire axial direction at multiple positions in the tire circumferential direction. The mounting surface 13c of the hub 13 to which the wheel 16 is mounted is provided with hub-side uneven portions 30b that correspond to the wheel-side uneven portions 30a and that are uneven in the tire axial direction at multiple positions in the tire circumferential direction.

[0035] The wheel-side uneven portion 30a and the hub-side uneven portion 30b are complementary to each other in the tire axial direction to form an abutting uneven pair 30. The abutting uneven pair 30 extends in the tire radial direction and is provided around the entire circumference of the mounting surface 13c and the mounted surface 16c.

[0036] 5, the abutting concave-convex pair 30 has a groove portion 31 with a V-shaped cross section formed in the mounting surface 16c, and a protrusion 32 formed in the mounting surface 13c of the hub 13 and protruding complementarily with respect to the groove portion 31. In its cross-sectional shape, the abutting concave-convex pair 30 has a first inclined side 33 that inclines toward one side in the tire circumferential direction and toward one side in the tire axial direction, and a second inclined side 34 that inclines toward the other side in the tire circumferential direction and toward the other side in the tire axial direction.

[0037] The groove 31 is formed by a groove bottom 31a extending in the tire radial direction and a pair of inclined surfaces 31b, 31c inclined from the groove bottom 31a toward both sides in the tire circumferential direction, and is formed so that the overall V-shaped cross section continues in the circumferential direction. In this embodiment, the pair of inclined surfaces 31b, 31c are inclined so that both sides in the tire circumferential direction are located closer to the vehicle body inner side (hub 13 side) than the groove bottom 31a side.

[0038] The first inclined edge 33 and the second inclined edge 34 form part of the cross section of the pair of inclined surfaces 31b, 31c when viewed radially, and the inclined surface on one side of the pair of inclined surfaces 31b, 31c formed by the first inclined edge 33 is sometimes referred to as the first inclined surface 31b, and the inclined surface on the other side formed by the second inclined edge 34 is sometimes referred to as the second inclined surface 31c.

[0039] The grooves 31 are continuous in the circumferential direction, and therefore, protrusions 31d are formed between adjacent grooves 31 by the first inclined surface 31b on one circumferential side and the second inclined surface 31c on the other circumferential side. In other words, the wheel-side uneven portion 30a is formed by the grooves 31 and the protrusions 31d continuing in the circumferential direction.

[0040] The protrusion 32 is formed by an apex 32a extending in the tire radial direction and a pair of inclined surfaces 32b, 32c inclined from the apex 32a toward both sides in the tire circumferential direction, and is formed so that the cross section of an inverted V shape as a whole continues in the circumferential direction. In this embodiment, the pair of inclined surfaces 32b, 32c are inclined so that both sides in the tire circumferential direction are located closer to the vehicle body outer side (wheel 16 side) than the apex 32a side.

[0041] The first inclined edge 33 and the second inclined edge 34 form part of the cross section of the pair of inclined surfaces 31b, 31c when viewed radially, and of the pair of inclined surfaces 32b, 32c, the inclined surface on one side formed by the first inclined edge 33 is sometimes referred to as the first inclined surface 32b, and the inclined surface on the other side formed by the second inclined edge 34 is sometimes referred to as the second inclined surface 32c.

[0042] The protrusions 32 are continuous in the circumferential direction, and therefore, grooves 32d are formed between adjacent protrusions 32 by the first inclined surface 32b on one circumferential side and the second inclined surface 32c on the other circumferential side. In other words, the hub-side uneven portion 30b is formed by the protrusions 32 and the grooves 32d being continuous in the circumferential direction.

[0043] The wheel side uneven portion 30a and the hub side uneven portion 30b are formed complementarily, so that the groove portion 31 of the wheel 16 corresponds to the protrusion 32 of the hub 13, and the protrusion 31d of the wheel 16 corresponds to the groove portion 32d of the hub 13.

[0044] 5, the inclination angle α1 of the first and second inclined surfaces 31b, 31c, 32b, and 32c with respect to a plane perpendicular to the axial direction of the tire is set to be larger than the lead angle β of the bolt 17. More specifically, the inclination angle α1 of the first and second inclined surfaces 31b, 31c, 32b, and 32c is set to be equal to or greater than 5° and equal to or smaller than 45°.

[0045] 4, the areas of the first and second inclined surfaces 31b, 31c, 32b, and 32c are enlarged from the inner side toward the outer side in the tire radial direction. An angle γ1 between the first and second inclined surfaces 31b, 31c, 32b, and 32c is set to be equal to or greater than 10° and equal to or less than 20°.

[0046] As shown in the enlarged view of Figure 5, when the hub 13 and the wheel 16 are misaligned in the rotational direction due to braking or the like, the first inclined surfaces 31b, 32b of the hub 13 and the wheel 16 move circumferentially. At this time, because the angle α1 of the first inclined surfaces 31b, 32b of the hub 13 and the wheel 16 is designed to be larger than the lead angle β of the bolt 17, a relative misalignment occurs between the hub 13 and the wheel 16, with the first inclined surface 31b of the wheel 16 climbing up the first inclined surface 32b of the hub 13. However, because the angle α1 of the first inclined surfaces 31b, 32b is greater than the lead angle β, before the bolt 17 loosens, the thickness H11 between the hub 13 and the wheel 16 on which the bolt 17 is seated increases by the amount that the first inclined surface 31b of the wheel 16 climbs up the first inclined surface 32b of the hub 13. The bolt 17 is stretched by the amount of the increase in thickness H11, and the axial force increases due to the elastic force generated at the same time. As a result, the axial force increases as the hub 13 and the wheel 16 try to deviate in the rotational direction, thereby suppressing the deviation in the rotational direction between the hub 13 and the wheel 16. A so-called self-locking effect is achieved by the Nord-Lock washer.

[0047] Furthermore, when the bolt 17 rotates backward due to vibration or the like, the first inclined surfaces 31b, 32b of the hub 13 and the wheel 16 move circumferentially. At this time, because the angle α1 between the first inclined surfaces 31b, 32b of the hub 13 and the wheel 16 is designed to be larger than the lead angle β of the bolt 17, a relative displacement occurs between the hub 13 and the wheel 16, such that the first inclined surface 31b of the wheel 16 moves up the first inclined surface 32b of the hub 13. However, because the angle α1 between the first inclined surfaces 31b, 32b of the wheel 16 and the hub 13 is larger than the lead angle β, before the bolt 17 loosens, the thickness H11 between the hub 13 and the wheel 16 on which the bolt 17 is seated increases by the amount that the first inclined surface 31b of the wheel 16 moves up the first inclined surface 32b of the hub 13. The bolt 17 is stretched by the amount of the increase in thickness H11, and the axial force increases due to the elastic force generated at the same time. This increases the axial force as the hub 13 and wheel 16 tend to shift in the rotational direction, suppressing the rotational shift between the hub 13 and wheel 16 due to the return rotation of the bolt 17. This provides a so-called self-locking effect with the Nord-Lock washer.

[0048] The width W1 of the protrusion 31d of the wheel 16 at the tire radial position overlapping with the bolt 17 is set to be larger than the diameter D of the bolt 17. If the width W1 is equal to or smaller than the diameter D of the bolt 17, damage to the bolt 17 due to misalignment between the hub 13 and the wheel 16 in the rotational direction cannot be prevented.

[0049] The above configuration makes it possible to increase the contact area between the hub 13 and the wheel 16 compared to when no contact concave-convex pair 30 is provided. This increases the frictional force between the hub 13 and the wheel 16, making it easier to resist misalignment in the rotational direction of the hub 13 and the wheel 16 under braking and driving conditions in the tire testing device 1, and preventing damage to the bolts 17 that secure them together.

[0050] Furthermore, by providing the contact concave-convex pairs 30 that extend radially and are continuous in the circumferential direction, the contact area between the hub 13 and the wheel 16 can be increased compared to when the contact concave-convex pairs 30 are provided on only a portion of the mounting surface 13c and the mounted surface 16c. This can further increase the frictional force between the hub 13 and the wheel 16. Because the first and second inclined surfaces 31b, 31c, 32b, 32c are provided on both sides in the circumferential direction, the frictional force between the hub 13 and the wheel 16 can be increased regardless of the rotational direction of the tire.

[0051] The first and second inclination angles α1 are set to be equal to or greater than 5° and equal to or less than 45°, thereby ensuring the self-locking effect. If the first and second inclination angles α1 are less than the lead angle of the bolt 17 of 5° (the lower limit), the bolt 17 will loosen, making it difficult to increase the axial tension. If the first and second inclination angles α1 are greater than 45°, the hub-side uneven portion 30b and the wheel-side uneven portion 30a will fit together, preventing the effect of friction.

[0052] In the first embodiment, it was explained that the abutting concave-convex pair 30 is provided around the entire circumference of the mounting surface 13c of the hub 13 and the mounted surface 16c of the wheel 16, but this is not limited to this, and the abutting concave-convex pair 30 may also be provided intermittently between adjacent pairs of bolts 17 among the multiple bolts 17.

[0053] In the first embodiment, it was described that the inclination angles α1 of the first inclined edge 33 and the second inclined edge 34 are the same, but this is not limited to this. As in the first modified example shown in Figure 6, in the cross-sectional shape of the abutting concave-convex pair 40, the second inclination angle α2 of the second inclined edge 44, which inclines toward the other side in the tire axial direction toward the other side in the tire circumferential direction, relative to a plane perpendicular to the tire axial direction may be set to be larger than the first inclination angle α1 of the first inclined edge 43, which inclines toward one side in the tire axial direction toward one side in the tire circumferential direction.

[0054] As in a second modified example shown in Fig. 7, the contacting concave-convex pairs 50 may be formed in a radial spiral shape so that the inner side in the tire radial direction is located further forward in the tire rotation direction than the outer side as indicated by arrow R in Fig. 7 when viewed from the tire axial direction, or the contacting concave-convex pairs 50 may be formed in a radial spiral shape so that the inner side in the tire radial direction is located further rearward in the tire rotation direction than the outer side as indicated by arrow R in Fig. 7 when viewed from the tire axial direction. With this configuration, the distance from the radially inner side to the radially outer side of the contacting concave-convex pairs 50 is increased compared to when the concave-convex portions are provided linearly, thereby increasing the contact area.

[0055] In the first embodiment, it has been described that a plurality of contact concave-convex pairs 30 are formed in the circumferential direction, but this is not limiting, and as in a third modified example shown in Fig. 8, the contact concave-convex pair 60 (wheel-side concave-convex portion 60a, hub-side concave-convex portion 60b) may be conical with the tire rotation axis as its center. More specifically, the contact concave-convex pair 60 may be formed by groove portions 61 formed in a conical shape that deepens from the outer side toward the inner side in the tire radial direction on the mounting surface 16c of the wheel 16, and protrusions 62 formed in a conical shape that protrudes more from the outer side toward the inner side in the tire radial direction on the mounting surface 13c of the hub 13.

[0056] Furthermore, as in the fourth modified example shown in Figure 9, the abutting concave-convex pair 70 (wheel side concave-convex portion 70a, hub side concave-convex portion 70b) may be formed by a groove portion 71 formed in a conical shape on the mounting surface 13c of the hub 13, the depth of which decreases from the outside to the inside in the tire radial direction, and a protrusion 72 formed in a conical shape on the mounting surface 16c of the wheel 16, the protrusion amount of which increases from the outside to the inside in the tire radial direction.

[0057] The depth H2 of the grooves 61, 71 is set, for example, between 8 mm and 50 mm. If the depth H2 is less than 8 mm, the increase in contact area is small, making it difficult to prevent misalignment of the hub 13 and the wheel 16 in the rotational direction. If the depth H2 is greater than 50 mm, the rigidity of the grooved side of the hub 13 or the wheel 16 decreases. With this configuration, the mounting surface 13c of the hub 13 and the mounted surface 16c of the wheel 16 are formed as inclined surfaces, which increases the contact area between the hub 13 and the wheel 16 compared to when the mounting surface 13c of the hub 13 and the mounted surface 16c of the wheel 16 are formed as flat surfaces. This increases the frictional force between the hub 13 and the wheel 16.

[0058] [Second embodiment] 10 shows the configuration of a tire support unit 12 of a tire testing apparatus according to the second embodiment. The tire testing apparatus differs from the tire testing apparatus 1 according to the first embodiment in the mounting surface 13c of the hub 13 and the mounted surface 16c of the wheel 16. Hereinafter, the same reference numerals will be used for the components common to the tire testing apparatus 1, and their description will be omitted.

[0059] Figure 10 is a view of the mounting surface 16c mounted on the hub of the wheel 16 as viewed from the tire axial direction (the direction of arrow IV in Figure 3). Referring to Figure 11 in addition to Figure 10, the mounting surface 16c is provided with wheel-side uneven portions 80a that are uneven in the tire axial direction at multiple positions in the tire circumferential direction. The mounting surface 13c of the hub 13 to which the wheel 16 is mounted is provided with hub-side uneven portions 80b that correspond to the wheel-side uneven portions 80a and that are uneven in the tire axial direction at multiple positions in the tire circumferential direction.

[0060] The wheel-side concave-convex portion 80a and the hub-side concave-convex portion 80b are complementary to each other so as to fit together in the tire axial direction, constituting a mating concave-convex pair 80. The mating concave-convex pairs 80 extend in the tire radial direction and are each provided between a pair of adjacent bolts 17 among the multiple bolts 17.

[0061] 11, the fitting recess-protrusion pair 80 has a groove portion 81 with a V-shaped cross section formed in the mounting surface 16c, and a protrusion portion 82 formed in the mounting surface 13c of the hub 13 and protruding complementarily with respect to the groove portion 81. In its cross-sectional shape, the fitting recess-protrusion pair 80 has a first inclined side 83 that inclines toward one side in the tire circumferential direction and toward one side in the tire axial direction, and a second inclined side 84 that inclines toward the other side in the tire axial direction and toward the other side in the tire circumferential direction.

[0062] The groove 81 is formed by a groove bottom 81a extending in the tire radial direction and a pair of inclined surfaces 81b, 81c inclined from the groove bottom 81a toward both sides in the tire circumferential direction, and is formed so that the overall V-shaped cross section continues in the circumferential direction. In this embodiment, the pair of inclined surfaces 81b, 81c are inclined so that both sides in the tire circumferential direction are located closer to the vehicle body inner side (hub 13 side) than the groove bottom 81a side.

[0063] The first inclined edge 83 and the second inclined edge 84 constitute part of the cross section of the pair of inclined surfaces 81b, 81c when viewed radially, and the inclined surface on one side of the pair of inclined surfaces 81b, 81c constituted by the first inclined edge 83 is sometimes referred to as the first inclined surface 81b, and the inclined surface on the other side constituted by the second inclined edge 84 is sometimes referred to as the second inclined surface 81c.

[0064] The protrusion 82 is formed by an apex 82a extending in the tire radial direction and a pair of inclined surfaces 82b, 82c inclined from the apex 82a toward both sides in the tire circumferential direction, and is formed so that the overall inverted V-shaped cross section continues in the circumferential direction. In this embodiment, the pair of inclined surfaces 82b, 82c are inclined so that both sides in the tire circumferential direction are located closer to the vehicle body outer side (wheel 16 side) than the apex 82a side.

[0065] The first inclined edge 83 and the second inclined edge 84 form part of the cross section of the pair of inclined surfaces 81b, 81c when viewed radially, and of the pair of inclined surfaces 82b, 82c, the inclined surface on one side formed by the first inclined edge 83 is sometimes referred to as the first inclined surface 82b, and the inclined surface on the other side formed by the second inclined edge 84 is sometimes referred to as the second inclined surface 82c. It is being done.

[0066] The wheel-side uneven portion 80 a and the hub-side uneven portion 80 b are formed to be complementary, so that the grooves 81 of the wheel 16 correspond to the protrusions 82 of the hub 13 .

[0067] As shown in FIG. 11, the inclination angle α3 of the first and second inclined surfaces 81b, 81c, 82b, 82c relative to a plane perpendicular to the axial direction of the tire is set to be equal to or greater than 30° and equal to or less than 75°.

[0068] 10, the areas of the first and second inclined surfaces 81b, 81c, 82b, and 82c increase from the inner side toward the outer side in the tire radial direction. An angle γ2 between the first and second inclined surfaces 81b, 81c, 82b, and 82c is set to be equal to or greater than 20° and equal to or less than 45°.

[0069] The width W2 of the protrusion 82 (the distance between the lower ends of the pair of inclined surfaces 81b, 81c) at the tire radial position overlapping with the bolt 17 is set to be equal to or greater than the diameter D of the bolt 17 and equal to or less than half the distance L between adjacent bolts 17. If the width W2 is equal to or less than the stud bolt diameter D, damage to the bolt 17 due to misalignment in the rotational direction between the hub 13 and the wheel 16 cannot be prevented. If the width W2 is greater than half the distance L between the bolts 17, the rigidity of the attached portion 16c of the wheel 16 decreases.

[0070] The height H3 of the protrusion 82 at the tire radial position overlapping with the bolt 17 is preferably set to 3 mm or more and 40 mm or less. If it is less than 3 mm, it is difficult to resist misalignment in the rotational direction of the hub 13 and wheel 16 due to the engagement of the abutting concave-convex pair 80. If it is more than 40 mm, assembly is hindered. The height H3 of the protrusion 82 is the distance in the tire axial direction from the apex 81 a to the lower ends of the inclined surfaces 82 b, 82 c.

[0071] With the above configuration, by fitting the hub 13 and the wheel 16 in the tire axial direction, it is easy to resist rotational misalignment (shear force) between them in the tire rotation direction. More specifically, the shear force due to rotational misalignment between the hub 13 and the wheel 16 in the rotation direction can be borne by the fitting recess-projection pair 80 in addition to the bolt 17. Therefore, under braking and driving conditions in the tire testing device 200, it is easy to resist positional misalignment between them in the rotation direction, and damage to the bolt 17 that secures them together is prevented.

[0072] Furthermore, damage to the bolts 17 that secure the hub 13 and wheel 16 can be prevented by a simple structure in which complementary mating recess-projection pairs 80 are provided on the hub 13 and wheel 16. Furthermore, the V-shape can guide the wheel 16 during assembly, making it easy to assemble the wheel 16 to the hub 13.

[0073] In the second embodiment, the fitting concave-convex pair 80 is described as having the protrusion 82 on the hub 13 side, but this is not limited thereto, and the wheel 16 side may be formed with a protrusion that protrudes toward the hub 13 side. In this case, it is sufficient that the groove portion of the hub 13 is formed to complementarily fit with the protrusion portion of the wheel 16.

[0074] In the second embodiment, it has been described that the mating concave-convex pair 80 is formed with a V-shaped cross section, but this is not limited to this. As shown by the imaginary line in Figure 11, the mating concave-convex pair 80 may also have a rectangular cross section formed on the mounting surface 16c of the wheel 16.

[0075] In the second embodiment, it has been described that the mating concave-convex pair 80 has one groove 81 and one protrusion 82 between each pair of circumferentially adjacent bolts 17, but this is not limited to this, and as in a fifth modified example shown in Fig. 12, the mating concave-convex pair 90 (wheel-side mating concave-convex pair 90a and hub-side mating concave-convex pair 90b) may have multiple grooves 91 and multiple protrusions 92 between each pair of circumferentially adjacent bolts 17. In this case, the height H4 of the protrusion 92 is set to be equal to or greater than 3 mm and equal to or less than 15 mm, and the width W3 of the protrusion 92 is set to be equal to or greater than 3 mm and equal to or less than 30 mm.

[0076] [Third embodiment] 13 shows the configuration of a tire support unit 12 of a tire testing apparatus according to the third embodiment. The tire testing apparatus differs from the tire testing apparatus 1 according to the first embodiment in the mounting surface 13c of the hub 13 and the mounted surface 16c of the wheel 16. Hereinafter, the same reference numerals will be used for the components common to the tire testing apparatus 1, and their description will be omitted.

[0077] Figure 13 is a view of the mounting surface 16c mounted on the hub of the wheel 16 as viewed from the tire axial direction (the direction of arrow IV in Figure 3). Referring to Figure 14 in addition to Figure 13, the mounting surface 16c is provided with wheel-side uneven portions 100a that are uneven in the tire axial direction at multiple positions in the tire circumferential direction. The mounting surface 13c of the hub 13 to which the wheel 16 is mounted is provided with hub-side uneven portions 100b that correspond to the wheel-side uneven portions 100a and that are uneven in the tire axial direction at multiple positions in the tire circumferential direction.

[0078] The wheel-side concave-convex portion 100a and the hub-side concave-convex portion 100b constitute a mating concave-convex pair 100 that are complementary to each other so as to fit together in the tire axial direction. The mating concave-convex pair 100 has a groove portion 101 that is provided on the wheel 16 and extends in the tire axial direction, and a protrusion portion 102 that is provided on the hub 13 and fits into the groove portion 101. The mating concave-convex pair 100 is provided between each pair of circumferentially adjacent bolts 17 among the multiple bolts 17.

[0079] It is preferable that at least a portion of the mating concave-convex pair 100 is provided at a radial position that overlaps with the bolt 17, and in this embodiment, as shown in Figure 13, the mating concave-convex pair 100 is provided so that the radial directions of the mating concave-convex pair 100 and the bolt 17 coincide.

[0080] As shown in Fig. 13, the fitting recess-projection pair 100 has an elliptical shape when viewed from the tire axial direction. The radial dimension D1 of the protrusion 101 at the tire radial position overlapping with the bolt 17 is set to be larger than the bolt diameter D. More specifically, the radial dimension D1 is set to be 16 mm or more and 42 mm or less. The circumferential dimension D2 of the protrusion 101 is set to be 0.8 times or more and 1 time or less the radial dimension D1 of the protrusion 101. More specifically, the circumferential dimension D2 is set to be 14 mm or more and 42 mm or less.

[0081] The height H5 of the protrusion 102 at the tire radial position overlapping with the bolt 17 is preferably set to be equal to or greater than 3 mm and equal to or less than 40 mm.

[0082] According to the above configuration, similar to the second embodiment, by fitting the hub 13 and the wheel 16 in the tire axial direction, it is easy to resist rotational misalignment (shear force) between them in the tire rotation direction. More specifically, the shear force due to rotational misalignment between the hub 13 and the wheel 16 in the rotation direction can be borne by the fitting recess-projection pair 90 in addition to the bolt 17. Therefore, under braking and driving conditions in the tire testing device 300, it is easy to resist positional misalignment between them in the rotation direction, and damage to the bolt 17 that secures them is prevented.

[0083] Damage to the bolt 17 that secures the hub 13 and wheel 16 is prevented by a simple structure in which complementary mating concave-convex pairs 100 are provided on the hub 13 and wheel 16. Because the mating concave-convex pairs 100 are provided at radial positions that overlap the bolts 17, the mating concave-convex pairs 100 can more easily bear the shear force acting on the bolts 17.

[0084] In the third embodiment, the fitting concave-convex pair 100 is described as having the protrusion 102 on the hub 13 side, but this is not limited thereto, and the wheel 16 side may be formed with a protrusion that protrudes toward the hub 13 side. In this case, it is sufficient that the groove portion of the hub 13 is formed to fit complementarily with the protrusion portion of the wheel 16.

[0085] In the third embodiment, it has been described that the cross-sectional shape of the mating concave-convex pair 100 is rectangular, but this is not limited to this, and the cross-sectional shape of the mating concave-convex pair 100 may be arc-shaped as shown in FIG. 15(a), spherical as shown in FIG. 15(b), triangular in cross section with an apex on the radially outer side as shown in FIG. 15(c), triangular in cross section with an apex on the radially inner side as shown in FIG. 15(d), or trapezoidal as shown in FIG. 15(e).

[0086] The third embodiment may be combined with the first and second embodiments. That is, as shown in Fig. 16, a fitting concave-convex pair 100 for fitting the hub 13 and the wheel 16 in the tire axial direction may be combined with a contacting concave-convex pair 30 for increasing the contact area.

[0087] The present invention is not limited to the configurations described in the above embodiments, and various modifications are possible. [Explanation of symbols]

[0088] 1. Tire testing equipment 11 Running platform 12 Tire support part 13. Hub 16 wheels 17 volts 18 Nut 30 Contact concave and convex pair 30a Wheel side uneven part 30b Hub side uneven part 40 Contact concave and convex pair 40a Wheel side uneven part 40b Hub side uneven part 50 Concave and convex pair 50a Wheel side uneven part 50b Hub side uneven part 60 Contact concave and convex pair 70 Contact concave and convex pair 80 mating concave-convex pair 80a Wheel side uneven part 80b Hub side uneven part 90 Mating concave and convex pair 90a Wheel side uneven part 90b Hub side uneven part 100 mating concave-convex pair 100a Wheel side uneven part 100b Hub side uneven part X Tire under evaluation

Claims

1. a running platform on which the test tire is brought into contact; a wheel on which the tire to be evaluated is mounted on a rim; a tire support unit having a hub to which the wheel is attached and rotatably supporting the tire to be evaluated via the wheel and the hub; a plurality of fastening members for fastening the wheel to the hub at a plurality of positions in the tire circumferential direction; Equipped with the wheel has a wheel-side uneven portion that extends in the tire radial direction and has a predetermined cross-sectional shape that is uneven in the tire axial direction at one or more positions in the tire circumferential direction on a mounting surface that is attached to the hub, the hub has a hub-side uneven portion that extends in the tire radial direction and has a predetermined cross-sectional shape that is uneven in the tire axial direction at one or more positions in the tire circumferential direction on a mounting surface to which the wheel is mounted, A tire testing device, wherein the wheel-side concave-convex portion and the hub-side concave-convex portion form a complementary abutting concave-convex pair that abuts against each other in the tire axial direction.

2. The abutting concave-convex pair is In the cross-sectional shape, a first inclined side inclined toward one side in the tire circumferential direction; a second inclined side inclined toward one side in the tire axial direction toward the other side in the tire circumferential direction; having 2. The tire testing apparatus according to claim 1.

3. In the cross-sectional shape, the first inclined side is inclined at a first inclination angle with respect to a plane perpendicular to the tire axial direction, the second inclined side is inclined at a second inclination angle with respect to a plane perpendicular to the tire axial direction, the first tilt angle and the second tilt angle are greater than or equal to 5° and less than or equal to 45°; 3. The tire testing apparatus according to claim 2.

4. In the cross-sectional shape, the first inclined side is inclined at a first inclination angle with respect to a plane perpendicular to the tire axial direction, the second inclined side is inclined at a second inclination angle with respect to a plane perpendicular to the tire axial direction, The second tilt angle is set to be larger than the first tilt angle.

3. The tire testing apparatus according to claim 2.

5. The contact concave-convex pair extends spirally so that the inner side in the tire radial direction is located on one side of the outer side in the tire rotation direction when viewed from the tire axial direction. The tire testing device according to any one of claims 1 to 4.

6. The abutting concave-convex pair is It is a cone shape centered on the tire rotation axis, 2. The tire testing apparatus according to claim 1.

7. a running platform on which the test tire is brought into contact; a wheel on which the tire to be evaluated is mounted on a rim; a tire support unit having a hub to which the wheel is attached and rotatably supporting the tire to be evaluated via the wheel and the hub; a plurality of fastening members for fastening the wheel to the hub at a plurality of positions in the tire circumferential direction; Equipped with the wheel has a wheel-side uneven portion on a mounting surface attached to the hub, the wheel having a predetermined cross-sectional shape that is uneven in the tire axial direction; the hub has a hub-side uneven portion on a mounting surface to which the wheel is mounted, the hub having a predetermined cross-sectional shape that is uneven in the tire axial direction, A tire testing device, wherein the wheel-side concave-convex portion and the hub-side concave-convex portion form a complementary mating concave-convex pair that mate with each other in the tire axial direction.

8. The fitting recess-projection pair is located between the plurality of fastening members in the tire circumferential direction.

8. The tire testing apparatus according to claim 7.

9. The fitting concave-convex pair is In the cross-sectional shape, a first inclined side inclined toward one side in the tire circumferential direction; a second inclined side inclined toward one side in the tire axial direction toward the other side in the tire circumferential direction; having 9. The tire testing device according to claim 7 or 8.

10. The fitting concave-convex pair has a rectangular cross-sectional shape.

9. The tire testing device according to claim 7 or 8.

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