Tire

Abstract

A pneumatic tire (1) is provided with: a ridge region (50) in which a plurality of ridges (55) are disposed, the ridge region (50) being formed on a tire side section (31), which is the surface of a side wall section (30); and a plurality of protruding patterns (60) that are disposed in the ridge region (50) at a height that is higher than the height of the ridge (55) in the height direction of the ridge (55), and that extend in a direction that intersects the direction in which the ridge (55) extends. The plurality of protruding patterns (60) have a protruding pattern (60) in contact with an outline portion (51) on the outside of the ridge region (50) in the radial direction of the tire, and a protruding pattern (60) separated from the outline portion (51) of the ridge region (50), thereby suppressing deterioration of mold processability, suppressing propagation of cracks, and continuously maintaining an aesthetic appearance.

Description

Technical Field

[0001] This invention relates to tires. Background Technology

[0002] In recent years, there have been tires that have decorative raised patterns added to the surface of the sidewall to improve their appearance. For example, in the pneumatic tires described in Patent Documents 1 to 5, the surface of the sidewall has a decorative part with raised ridges.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent No. 5325129

[0006] Patent Document 2: Japanese Patent Application Publication No. 2006-347202

[0007] Patent Document 3: Japanese Patent No. 3614973

[0008] Patent Document 4: Japanese Patent No. 6047016

[0009] Patent Document 5: Japanese Patent No. 4640517 Summary of the Invention

[0010] The problem that the invention aims to solve

[0011] However, applying complex patterns to the sidewalls can worsen the machinability of the molds used for tire forming. Therefore, the decorative patterns applied to the sidewalls are preferably those that can be shaped with minimal mold processing time. However, if the decorative patterns are simple, it may be difficult to improve the aesthetics even if decoration is applied to the sidewalls.

[0012] Furthermore, and importantly, tires should maintain their aesthetic appearance not only when new but also during prolonged exposure to outdoor environments. In other words, during tire use, cracks may sometimes appear on the sidewall surface due to loads acting on it and years of deterioration. These cracks deteriorate the tire's appearance, making it difficult to maintain a consistent aesthetic. Therefore, it is challenging to maintain a consistently attractive appearance while simultaneously mitigating the deterioration of the mold's manufacturability when applying decorative finishes to the sidewall.

[0013] The present invention was made in view of the above circumstances, and its object is to provide a tire that can continuously maintain an aesthetic appearance while suppressing the deterioration of mold processability and the propagation of cracks.

[0014] Methods for solving problems

[0015] To solve the aforementioned problems and achieve the objective, the tire of the present invention is characterized by comprising: a ridge region formed on a tire sidewall surface, wherein a plurality of ridges are disposed in the ridge region; and a plurality of raised patterns disposed in the ridge region at a height greater than the height of the ridges in the height direction of the ridges, and extending in a direction intersecting the extension direction of the ridges, wherein the plurality of raised patterns have: raised patterns that are in contact with the outline portion of the tire radially outer side of the ridge region; and raised patterns that are separate from the outline portion of the ridge region.

[0016] Furthermore, in the above-mentioned tire, it is preferable that a smooth surface area is formed on the side of the tire, the smooth surface area being a planar area whose height in the height direction of the ridge is higher than the height of the ridge, and the height of the raised tread pattern in the height direction of the ridge relative to the height of the smooth surface area is within the range of ±0.80mm.

[0017] Furthermore, in the tires described above, it is preferable that adjacent tread patterns are arranged parallel to each other.

[0018] Furthermore, in the above-mentioned tire, it is preferable that the spacing P of the plurality of ridges disposed in the ridge region is in the range of 0.55mm≤P≤1.50mm, and the ratio H / B of the height H of the ridge to the width B of the ridge is in the range of 0.60≤H / B≤1.40.

[0019] Furthermore, in the tire described above, it is preferable that the raised tread pattern is alternately formed with wide and narrow portions in the extending direction of the raised tread pattern, and the width of the narrow portion in the direction intersecting the extending direction of the raised tread pattern is narrower than the width of the wide portion.

[0020] Furthermore, in the aforementioned tire, it is preferable that, regarding the raised tread pattern, the ratio d / D of the width D of the wide portion to the width d of the narrow portion is within the range of 0.10 ≤ d / D ≤ 0.50.

[0021] Furthermore, in the aforementioned tire, it is preferable that the spacing X of the plurality of raised tread patterns is within the range of 1.00mm ≤ X ≤ 5.00mm.

[0022] Furthermore, in the tire described above, it is preferable that, with respect to the tread pattern, adjacent tread patterns are arranged parallel to each other, and with respect to a plurality of tread patterns, the ratio D / X of the width D of the wide portion to the spacing X of the plurality of tread patterns is in the range of 0.20≤D / X≤5.00.

[0023] Furthermore, in the tire described above, it is preferable that, regarding the tread pattern, the length L1 of the wide portion and the length L2 of the narrow portion in the extending direction of the tread pattern satisfy the relationship 0.30≤L1 / (L1+L2)≤0.70.

[0024] Furthermore, in the aforementioned tire, it is preferable that, with respect to the plurality of tread patterns, the wide portion of one side of the tread pattern and the narrow portion of the tread pattern of the other side of the adjacent tread patterns have portions that are located at the same position relative to each other in the tire radial direction.

[0025] Invention Effects

[0026] The tire of the present invention has the following effect: it can suppress the deterioration of mold processability while suppressing the expansion of cracks and maintaining a beautiful appearance. Attached Figure Description

[0027] Figure 1 This is a meridional sectional view showing the main part of the pneumatic tire according to the embodiment.

[0028] Figure 2 yes Figure 1 AA view.

[0029] Figure 3 yes Figure 1 The AA view is an explanatory diagram showing the state of the ridge with the ridge region omitted.

[0030] Figure 4 yes Figure 2 Detailed diagram of Part B.

[0031] Figure 5 It is a cross-sectional view of the ridge when viewed along its extension direction.

[0032] Figure 6 yes Figure 2 The detailed diagram in section B is an explanatory diagram showing the state of the ridge with the ridge region omitted.

[0033] Figure 7 This is a schematic cross-sectional view of a tire forming mold that is part of a pneumatic tire manufacturing system.

[0034] Figure 8 This is a variation of the pneumatic tire according to the embodiment, and is an explanatory diagram showing the formation of raised patterns of a certain width in the ridge area.

[0035] Figure 9 It is a graph showing the results of performance evaluation tests on pneumatic tires. Detailed Implementation

[0036] Hereinafter, embodiments of the tire of the present invention will be described in detail based on the accompanying drawings. However, the present invention is not limited to these embodiments. Furthermore, the constituent elements in the following embodiments include constituent elements that can be substituted and readily conceived by those skilled in the art, or substantially the same constituent elements.

[0037] [Implementation Method]

[0038] [Pneumatic tire]

[0039] In the following description, an inflatable tire 1 will be used as an example of the tire of the present invention. The inflatable tire 1, as an example of a tire, can be filled with inactive gases such as air and nitrogen, as well as other gases.

[0040] In the following description, the tire radial direction refers to the direction orthogonal to the tire rotation axis (not shown), which is the axis of rotation of the pneumatic tire 1. The inner side of the tire radial direction refers to the side facing the tire rotation axis in the tire radial direction, and the outer side of the tire radial direction refers to the side away from the tire rotation axis in the tire radial direction. The tire circumferential direction refers to the direction around the tire rotation axis. The tire width direction refers to the direction parallel to the tire rotation axis. The inner side of the tire width direction refers to the side facing the tire equatorial plane (tire equator line) CL in the tire width direction, and the outer side of the tire width direction refers to the side away from the tire equatorial plane CL in the tire width direction. The tire equatorial plane CL is a plane orthogonal to the tire rotation axis and passing through the center of the tire width of the pneumatic tire 1. The position of the tire equatorial plane CL in the tire width direction coincides with the position of the tire width direction centerline, which is the center position in the tire width direction of the pneumatic tire 1. The tire width is the width of the outermost portions in the tire width direction relative to each other, that is, the distance between the portions farthest from the tire equatorial plane CL in the tire width direction. The tire equator is a line located on the tire equatorial plane CL and along the circumference of the pneumatic tire 1. Furthermore, in the following description, the tire meridional section refers to the cross-section of the tire cut by a plane containing the tire's axis of rotation.

[0041] Figure 1 This is a meridional sectional view showing the main parts of the pneumatic tire according to an embodiment. Regarding Figure 1The pneumatic tire 1 shown has a tread portion 2 on the outermost part of the tire's radial direction when viewed in a meridional section. The surface of the tread portion 2, that is, the part that contacts the road surface when the vehicle (not shown) equipped with the pneumatic tire 1 is in motion, forms the tread surface 3. Multiple circumferential main grooves 25 extending circumferentially along the tire's circumference are formed on the tread surface 3, dividing the tread surface 3 into multiple land portions 20. Regarding the grooves formed on the tread surface 3, grooves other than the circumferential main grooves 25 may also be formed, such as transverse grooves extending along the tire's width direction (not shown), or fine grooves different from the circumferential main grooves 25 (not shown).

[0042] The shoulder portion 8 is located at both ends of the tread portion 2 in the tire width direction, and a sidewall portion 30 is provided on the radially inner side of the shoulder portion 8. That is, the sidewall portion 30 is provided at both sides of the pneumatic tire 1 in the tire width direction. The outer surface of the sidewall portion 30 is formed into a tire side portion 31, which is located on both sides in the tire width direction. The two tire side portions 31 are located on opposite sides of each sidewall portion 30 in the tire width direction facing the side where the tire equatorial plane 5 is located.

[0043] In this case, the tire sidewall 31 refers to a surface that is uniformly continuous from the contact patch end T of the tread portion 2 outward in the tire width direction and from the rim inspection line R outward in the tire radial direction. Furthermore, the contact patch end T refers to the area where the pneumatic tire 1 is assembled onto a standard rim (Japanese: ). And filled with normal internal pressure (Japanese: And a normal load was applied (Japanese: When the tire tread surface 3 of the pneumatic tire 1 is in contact with the road surface at 70% of the tire width tread 2, the two outermost ends of the contact end T in the tire width direction are continuous in the tire circumferential direction. In addition, the rim inspection line R is a line used to confirm whether the tire rim assembly has been performed properly. Generally, it is shown as a continuous annular raised line in the tire circumferential direction along the radially outer side of the tire, which is closer to the rim flange than the rim flange (not shown in the figure), and is located near the rim flange.

[0044] In addition, standard rims refer to those specified by JATMA. (Applicable rim)", TRA's "Design Rim", or ETRTO's "Measuring Rim". Additionally, the standard internal pressure refers to the "JATMA" standard. (Maximum tire pressure), the maximum value of "TIRE LOAD LIMITS AT VARIOUSCOLD INFLATION PRESSURES" as specified by TRA, or "INFLATION PRESSURES" as specified by ETRO. Additionally, the normal load refers to the "JATMA" specification. (Maximum load capacity), the maximum value of "TIRE LOAD LIMITS AT VARIOUS COLDINFLATION PRESSURES" as specified by TRA, or "LOAD CAPACITY" as specified by ETRTO.

[0045] The bead portion 10 is located radially inner to each sidewall portion 30 on both sides of the tire width direction. The bead portion 10 is similarly disposed on both sides of the tire equatorial plane 5, just like the sidewall portions 30. Each bead portion 10 is provided with a bead core 11, and a bead filler 12 is provided radially outer to the bead core 11.

[0046] Furthermore, multiple belt layers 14 are provided on the radially inner side of the tire tread 2. The belt layers 14 are provided by stacking multiple intersecting belts 141, 142 with a belt cover 143. The intersecting belts 141, 142 are formed by covering multiple belt cords made of steel or organic fiber material with a cover rubber and then calendering them, and are configured to have a belt angle with an absolute value of 20° or more and 55° or less. The multiple intersecting belts 141, 142 are configured with a so-called intersecting ply structure: the belt angles, defined as the angle of inclination of the fiber direction of the belt cords relative to the tire circumference, are different from each other, and the fiber directions of the belt cords are intersected and stacked. The belt cover 143 is formed by calendering multiple cords made of steel or organic fiber material covered with a cover rubber, and has a belt angle with an absolute value of 0° or more and 10° or less. The belt cover 143 is stacked on the radial outer side of the tires of the cross belts 141 and 142.

[0047] A tire carcass 13, which encloses the cords of the radial ply, is continuously provided on the radial inner side of the belt layer 14 and on the equatorial plane 5 side of the sidewall portion 30. The tire carcass 13 has a single-layer structure formed by one tire carcass ply or a multi-layer structure formed by stacking multiple tire carcass ply layers, and is arranged in a ring shape between the bead cores 11 located on both sides in the tire width direction to form the tire skeleton. Specifically, the tire carcass 13 is disposed across one bead portion 10 located on both sides in the tire width direction, extending to the other bead portion 10, and folds back along the bead core 11 towards the outer side in the tire width direction at the bead portion 10, enclosing the bead core 11 and the bead filler 12. The portion of the tire carcass 13 that folds back towards the bead core 11 towards the outer side in the tire width direction is called a fold-back portion 18, which extends to the radial outer side of the bead filler 12. Therefore, the radially outer end 18a of the folded-back portion 18 is located radially outer of the tire than the bead filler 12, and is located near the portion of the sidewall portion 30 that is the widest part in the tire width direction of the pneumatic tire 1. Furthermore, the carcass ply of the carcass 13 is formed by covering multiple carcass cords made of steel, or organic fiber materials such as aramid, nylon, polyester, or synthetic fibers, with a covering rubber and then calendering them. The angle of inclination of the fiber direction of the carcass cords relative to the tire circumference, i.e., the carcass angle, is formed with an absolute value of 80° or more and 95° or less.

[0048] Rim buffer rubber 17 is provided on the inner radial side of the bead core 11 in the bead portion 10 and on the outer side of the folded portion of the tire carcass 13 in the tire width direction, forming a contact surface for contact between the bead portion 10 and the rim flange. In addition, an inner liner 15 is formed along the tire carcass 13 on the inner side of the tire carcass 13, or on the inner side of the tire carcass 13 in the pneumatic tire 1.

[0049] Figure 2 yes Figure 1 The view is shown in direction AA. On the tire sidewalls 31 located on both sides in the tire width direction, a smooth surface area 40 and a raised ridge area 50 are formed respectively for the purpose of improving the appearance of the pneumatic tire 1 and displaying various information. The smooth surface area 40 and the raised ridge area 50 are arranged in the same shape relative to the tire sidewalls 31 on both sides in the tire width direction. The smooth surface area 40 is a planar area with a base surface, and various information such as brand name, logo mark, and product name are displayed on the smooth surface area 40 to identify the pneumatic tire 1 or to display to the user.

[0050] The raised ridge region 50 is a decorative part used to improve the appearance of the pneumatic tire 1, and multiple raised ridges 55 are arranged in the raised ridge region 50 (see reference). Figure 4Multiple ridges 55 are arranged across the entire circumferential region of the ridge region 50. Furthermore, the ridge region 50, with a fixed width in the radial direction of the tire, is positioned circumferentially at a location different from that where the smooth surface region 40 is located. Moreover, information is indicated not only in the smooth surface region 40 but also, as needed, in the ridge region 50.

[0051] In this embodiment, smooth surface regions 40 are disposed at two locations on the tire sidewall 31 in the tire circumferential direction, and ridge regions 50 are disposed at locations between the two smooth surface regions 40 in the tire circumferential direction. In other words, the two smooth surface regions 40 are respectively disposed in the tire sidewall 31 in the region between the two ridge regions 50. The tire circumferential lengths of the areas where the two ridge regions 50 are disposed are of the same length, and the tire circumferential lengths of the areas where the two smooth surface regions 40 are disposed are also of the same length. Therefore, the areas in the tire sidewall 31 where the two smooth surface regions 40 and the two ridge regions 50 are disposed are point-symmetrical about the rotation axis of the pneumatic tire 1.

[0052] Furthermore, in this embodiment, the boundary portion between the smooth surface region 40 and the ridge region 50 extends radially along the tire while tilting circumferentially towards the tire. Therefore, at the boundary portion between the smooth surface region 40 and the ridge region 50, the smooth surface region 40 and the ridge region 50 are formed overlapping radially in the tire.

[0053] Figure 3 yes Figure 1 The AA view is an explanatory diagram showing the state of the ridge 55, with the ridge region 50 omitted. Figure 3 In order to facilitate identification of the raised pattern 60 disposed in the ridge region 50, the illustration of the ridge 55 is omitted. In the ridge region 50, besides the ridge 55 (see reference...), Figure 4 In addition to the ridge 50, it is also equipped with multiple raised patterns 60. The multiple raised patterns 60 configured in the ridge region 50 are configured to cover the entire range of the tire circumference of the ridge region 50 in the same way as the ridge 55.

[0054] Figure 4 yes Figure 2Detailed view of Part B. A plurality of ridges 55 are provided in the ridge region 50. These ridges 55 extend along the tire sidewall 31 in the shape of ridge-like protrusions and are arranged in the tire circumferential direction. The ridges 55 protrude from the tire sidewall 31 outward in the tire width direction or in the opposite direction to the tire cavity sidewall, i.e., outward of the tire, and are integrally provided with the tire sidewall 31. The inclination angle of the ridges 55 relative to the tire radial direction or relative to the tire circumferential direction is within a predetermined range. In the ridge region 50, adjacent ridges 55 are arranged at nearly parallel angles to each other, thus making them substantially parallel. By arranging the plurality of ridges 55 at approximately equal intervals in the tire circumferential direction, a tread pattern is formed by the plurality of ridges 55.

[0055] Furthermore, since the ridge region 50 is arranged along the tire circumference, the plurality of ridges 55 arranged in the ridge region 50 are arranged in a generally radial manner. However, if the relative angle between adjacent ridges 55 and the relative angle between the ridges 55 and their arrangement positions in the tire circumference direction are the same, the adjacent ridges 55 are considered to be substantially parallel to each other.

[0056] The tilt angle θ1 of the plurality of ridges 55 disposed in the ridge region 50 relative to the tire radial direction toward the tire circumference is in the range of 10° or more and 70° or less. Preferably, the tilt angle θ1 of the ridges 55 relative to the tire radial direction toward the tire circumference is in the range of 20° or more and 70° or less.

[0057] The raised tread pattern 60, located in the ridge region 50, protrudes outward from the tire sidewall 31 in the tire width direction, or outward from the tire sidewall, similar to the ridge 55, and is integrally formed on the tire sidewall 31. Furthermore, the raised tread pattern 60 is formed with a height relative to the tire sidewall 31 in the height direction of the ridge 55 that is greater than the height of the ridge 55. Therefore, the raised tread pattern 60 is formed to protrude outward from the tire sidewall 31 than the ridge 55. These raised tread patterns 60, formed in this way to protrude outward from the tire sidewall 31 than the ridge 55, extend along the tire sidewall 31, and multiple such patterns are arranged in a circumferential arrangement on the tire.

[0058] The raised tread pattern 60 extending along the tire sidewall 31 in the ridge region 50 extends in a direction intersecting the extending direction of the ridge 55. In this embodiment, the inclination direction of the raised tread pattern 60 relative to the tire radial direction toward the tire circumference is opposite to the inclination direction of the ridge 55 relative to the tire radial direction toward the tire circumference. For the plurality of raised tread patterns 60 whose inclination direction relative to the tire radial direction toward the tire circumference is opposite to the inclination direction of the ridge 55, their inclination angle θ2 relative to the tire radial direction toward the tire circumference is in the range of 10° or more and 80° or less. Preferably, the inclination angle θ2 of the raised tread pattern 60 relative to the tire radial direction toward the tire circumference is in the range of 20° or more and 70° or less.

[0059] Multiple raised tread patterns 60 disposed in the ridge region 50 extend in a direction intersecting the ridges 55, and adjacent raised tread patterns 60 are arranged at nearly parallel angles to each other. Thus, adjacent raised tread patterns 60 are arranged substantially parallel to each other, and the multiple raised tread patterns 60 are arranged at approximately equal intervals in the tire circumferential direction. Therefore, in the ridge region 50, a tread pattern is formed not only by the multiple ridges 55 but also by the multiple raised tread patterns 60. That is, in the ridge region 50, the multiple ridges 55 and the multiple raised tread patterns 60 together form a tread pattern.

[0060] Furthermore, since the ridge region 50 is arranged along the tire circumference, the plurality of raised patterns 60 arranged in the ridge region 50 are arranged in a generally radial manner, similar to the ridge 55. However, if the relative angle between adjacent raised patterns 60 and the relative angle between the circumferential arrangement positions of the raised patterns 60 and each other are the same, the adjacent raised patterns 60 are considered to be substantially parallel to each other.

[0061] Furthermore, the plurality of raised patterns 60 disposed in the ridge region 50 have: raised patterns 60 that are in contact with the outline portion 51 of the radial outer side of the tire in the ridge region 50; and raised patterns 60 that are separate from the outline portion 51 of the ridge region 50. That is, the plurality of raised patterns 60 have: contact raised patterns 60a as raised patterns 60 that are in contact with the outline portion 51 of the tire in the radial outer side of the tire in the ridge region 50; and non-contact raised patterns 60b as raised patterns 60 that are separate from the outline portion 51 of the tire in the ridge region 50. These contact raised patterns 60a and non-contact raised patterns 60b are alternately arranged in the tire circumferential direction. In addition, the distances in the tire circumferential direction from the outline portion 51 of the radial outer side of the tire in the ridge region 50 to the plurality of non-contact raised patterns 60b are the same size among the non-contact raised patterns 60b.

[0062] Furthermore, the plurality of raised tread patterns 60 disposed in the ridge region 50 are all separated from the radially inner contour portion 52 of the tire in the ridge region 50. That is, both the plurality of contact raised tread patterns 60a and the plurality of non-contact raised tread patterns 60b are separated from the radially inner contour portion 52 of the tire in the ridge region 50. In addition, regarding the distance of the raised tread pattern 60 from the radially inner contour portion 52 of the tire in the ridge region 50 in the tire circumferential direction, adjacent raised tread patterns 60 in the tire circumferential direction are different from each other.

[0063] Furthermore, in this case, the tire radially outer contour portion 51 of the ridge region 50 is shown by an imaginary line connecting the tire radially outer ends of each of the plurality of ridges 55 disposed in the ridge region 50. Similarly, the tire radially inner contour portion 52 of the ridge region 50 is also shown by an imaginary line connecting the tire radially inner ends of each of the plurality of ridges 55 disposed in the ridge region 50.

[0064] Figure 5 This is a cross-sectional view of the ridge 55 when viewed along its extension direction. The smooth surface region 40 formed on the tire sidewall 31 is a planar region in which the height S of the smooth surface region 40 in the height direction of the ridge 55 is higher than the height H of the ridge 55. In this case, the height H of the ridge 55 and the height S of the smooth surface region 40 are the heights in the direction from the base surface 53 of the ridge region 50 toward the outer side of the tire.

[0065] The base surface 53 of the ridge region 50 is the surface that serves as the root of the ridge 55 within the ridge region 50, and is a surface that is recessed from the contour line (not shown) towards the inner cavity of the tire. The contour line refers to... Figure 1 In the tire meridional section shown, the outline smoothly connects the shoulder portion 8 and the bead portion 10. The outline is composed of one or more arcs. The outline is defined in a way that eliminates local unevenness. The height H of the ridge 55 from the base surface 53 is preferably in the range of 0.50 mm or more and 1.00 mm or less, and the height S of the smooth surface region 40 from the base surface 53 is preferably in the range of 0.70 mm or more and 1.20 mm or less.

[0066] Regarding the raised tread pattern 60 disposed in the ridge region 50, its height Y in the height direction of the ridge 55 is within ±0.80 mm relative to the height S of the smooth surface region 40. That is, the height Y of the raised tread pattern 60 disposed in the ridge region 50 is substantially the same as the height S of the smooth surface region 40. In this case, the height Y of the raised tread pattern 60 is the height in the direction from the base surface 53 of the ridge region 50 toward the outer side of the tire. Regarding the raised tread pattern 60 disposed in the ridge region 50, its height Y in the height direction of the ridge 55 is preferably within ±0.50 mm relative to the height S of the smooth surface region 40.

[0067] Furthermore, regarding the plurality of ridges 55 disposed in the ridge region 50, the period of arrangement of the ridges 55 in the direction of arrangement, i.e., the spacing P, is within the range of 0.55mm ≤ P ≤ 1.50mm. Moreover, regarding the ridges 55, the ratio H / B of the height H of the ridge 55 to the width B of the ridge 55 is within the range of 0.60 ≤ H / B ≤ 1.40. Furthermore, since the plurality of ridges 55 are arranged in a generally radial pattern, adjacent ridges 55 are strictly different at angles, and the spacing P varies depending on the position of the ridge 55 in the extension direction, but the spacing P of the ridges 55 is within the range of 0.55mm ≤ P ≤ 1.50mm regardless of its position in the extension direction.

[0068] Figure 6 yes Figure 2 The detailed view of Part B is an explanatory diagram showing the state of the ridge 55, with the ridge region 50 omitted. Figure 6 In order to easily identify the raised pattern 60 configured in the ridge region 50, and Figure 3 Similarly, the illustration of the ridge 55 is omitted. The raised patterns 60 disposed in the ridge region 50 have wide portions 61 and narrow portions 62 with different widths in the direction intersecting the extending direction of the raised patterns 60. The width of the narrow portions 62 in the direction intersecting the extending direction of the raised patterns 60 is narrower than the width of the wide portions 61. Each of the plurality of raised patterns 60 disposed in the ridge region 50 has a plurality of wide portions 61 and a plurality of narrow portions 62, which are alternately formed in the extending direction of the raised patterns 60. That is, regarding the plurality of raised patterns 60 disposed in the ridge region 50, both the contact raised patterns 60a and the non-contact raised patterns 60b have a plurality of wide portions 61 and a plurality of narrow portions 62, which are alternately formed in the extending directions of the contact raised patterns 60a and the non-contact raised patterns 60b.

[0069] In this embodiment, the plurality of contact protrusions 60a disposed in the ridge region 50 are all connected by the wide portion 61 to the outline portion 51 of the tire radially outer side of the ridge region 50.

[0070] Regarding the raised pattern 60 having a wide portion 61 and a narrow portion 62, the ratio d / D of the width D of the wide portion 61 to the width d of the narrow portion 62 is in the range of 0.10 ≤ d / D ≤ 0.50. Furthermore, the raised pattern 60 is formed such that the length L1 of the wide portion 61 in the extending direction of the raised pattern 60 and the length L2 of the narrow portion 62 in the extending direction of the raised pattern 60 satisfy the relationship 0.30 ≤ L1 / (L1+L2) ≤ 0.70.

[0071] Furthermore, the relationship between the length L1 of the wide portion 61 and the length L2 of the narrow portion 62 of the raised pattern 60 is preferably within the range of 0.35 ≤ L1 / (L1+L2) ≤ 0.65. In this embodiment, the length L1 of the wide portion 61 and the length L2 of the narrow portion 62 of the raised pattern 60 are of the same length.

[0072] Furthermore, regarding the plurality of raised tread patterns 60, the wide portion 61 of one adjacent raised tread pattern 60 and the narrow portion 62 of the other adjacent raised tread pattern 60 are positioned at the same location relative to each other in the tire radial direction. In this embodiment, the tire radial position of the wide portion 61 of one adjacent raised tread pattern 60 is the same as the tire radial position of the narrow portion 62 of the other adjacent raised tread pattern 60. In other words, the wide portion 61 of one adjacent raised tread pattern 60 and the narrow portion 62 of the other adjacent raised tread pattern 60 are adjacent in the tire circumferential direction, and the narrow portion 62 of one adjacent raised tread pattern 60 and the wide portion 61 of the other adjacent raised tread pattern 60 are adjacent in the tire circumferential direction.

[0073] Furthermore, regarding the plurality of raised tread patterns 60 arranged circumferentially in the ridge region 50, the period of arrangement of the raised tread patterns 60 in the direction of arrangement, i.e., the spacing X, is within the range of 1.00mm ≤ X ≤ 5.00mm. Additionally, regarding the plurality of raised tread patterns 60, the ratio D / X of the width D of the wide portion 61 to the spacing X of the plurality of raised tread patterns 60 is within the range of 0.20 ≤ D / X ≤ 5.00. Moreover, since the plurality of raised tread patterns 60 are arranged in a generally radial pattern, adjacent raised tread patterns 60 are strictly different at angles, and the spacing X varies depending on the position of the raised tread pattern 60 in the extension direction, but the spacing X of the raised tread patterns 60 is within the range of 1.00mm ≤ X ≤ 5.00mm regardless of its position in the extension direction of the raised tread patterns 60.

[0074] [Tire manufacturing methods]

[0075] Next, an example of the manufacturing method of the pneumatic tire 1 according to the embodiment will be described. Figure 7This is a schematic cross-sectional view of a tire forming mold 500, which is part of a manufacturing system for a pneumatic tire 1. The pneumatic tire 1 is manufactured by vulcanizing a green tire using the vulcanizing mold 500. The green tire is vulcanized while being disposed inside and supported by the mold 500. The mold 500 includes: a plurality of sector molds 501 arranged in the tire circumferential direction for forming the tread portion 2 of the pneumatic tire 1; and side molds 502 for forming the sidewall portion 30 of the pneumatic tire 1.

[0076] The sector mold 501 is a component formed by dividing a circular mold in the circumferential direction of the tire. Multiple sector molds 501 are arranged in the circumferential direction of the tire. Each of the multiple sector molds 501 is capable of moving radially along the tire. The sector mold 501 contacts the tread portion 2 of the pneumatic tire 1 by moving radially inward. The sector mold 501 moves radially outward from the tread portion 2 of the pneumatic tire 1. The multiple sector molds 501 are integrated by moving radially inward to form a circular mold. The multiple sector molds 501 are separated by moving radially outward.

[0077] The tread portion 2 is formed by a fan-shaped mold 501. The fan-shaped mold 501 has a protrusion that protrudes radially inward from the inner surface of the fan-shaped mold 501 opposite to the tread portion 2. Through the protrusion of the fan-shaped mold 501, a tread pattern design including circumferential main grooves 25 is formed on the tread portion 2.

[0078] The side mold 502 includes an upper side mold 502A and a lower side mold 502B. The pneumatic tire 1 is disposed between the upper side mold 502A and the lower side mold 502B. The upper side mold 502A moves upward to separate from the side wall portion 30 of the pneumatic tire 1. The upper side mold 502A moves downward to contact the side wall portion 30 of the pneumatic tire 1. The lower side mold 502B moves downward to separate from the side wall portion 30 of the pneumatic tire 1. The lower side mold 502B moves upward to contact the side wall portion 30 of the pneumatic tire 1.

[0079] The sidewall portion 30 is formed by a side mold 502. The side mold 502 has a protrusion and a recess on its inner surface opposite to the sidewall portion 30. The protrusion and a recess in the side mold 502 form a smooth surface region 40 and a ridge region 50 in the sidewall portion 30.

[0080] [Functions and Effects]

[0081] Next, the function and effects of the pneumatic tire 1 of the embodiment will be explained. In the pneumatic tire 1 of the embodiment, a raised ridge region 50 is formed on the tire side 31, thereby improving the aesthetic appearance. In particular, in the raised ridge region 50 of the pneumatic tire 1 of this embodiment, a plurality of raised ridges 55 intersect with a plurality of raised tread patterns 60, thereby improving the aesthetics of the raised ridge region 50 and reliably improving the appearance.

[0082] Here, when using the pneumatic tire 1, the load acting on the pneumatic tire 1 causes repeated deformation of the sidewall portion 30. In addition, the rubber composition constituting the pneumatic tire 1 may deteriorate over time due to prolonged use of the pneumatic tire 1. Cracks may sometimes appear in the ridge region 50 formed on the tire sidewall portion 31 due to the repeated deformation and deterioration of the aforementioned sidewall portion 30. The ridge region 50 is mainly provided to improve the aesthetic appearance of the pneumatic tire 1, but when cracks appear in the ridge region 50, the aesthetic appearance is easily deteriorated.

[0083] In this embodiment of the pneumatic tire 1, in addition to the ridges 55, a plurality of raised patterns 60 are provided in the ridge region 50. These raised patterns 60 extend at a height higher than the ridges 55 in a direction intersecting the extending direction of the ridges 55. Therefore, even if, for example, a crack occurs between adjacent ridges 55 and the crack extends along the extending direction of the ridges 55, the crack will stop extending when it reaches the raised pattern 60. As a result, long cracks can be suppressed in the ridge region 50, and aesthetic deterioration can be suppressed, thus maintaining a consistently aesthetic appearance.

[0084] On the other hand, in order to form raised patterns 60 in the ridge region 50, a portion for forming the raised patterns 60 needs to be formed in the mold for forming the ridge region 50 during the manufacture of the pneumatic tire 1. The portion in the mold for forming the ridge region 50 is formed in a shape that can form multiple ridges 55. In addition, forming the portion for forming the raised patterns 60 increases the mold processing time during mold manufacturing, and therefore the machinability during mold processing may easily deteriorate.

[0085] In this embodiment, the pneumatic tire 1 has a plurality of raised patterns 60 formed in the ridge region 50, which have contact raised patterns 60a that are in contact with the outline portion 51 on the radial outer side of the ridge region 50 and non-contact raised patterns 60b that are separate from the outline portion 51. Therefore, it is possible to suppress the deterioration of mold processability as a plurality of raised patterns 60 are arranged in the ridge region 50.

[0086] In other words, the raised tread pattern 60 has contact raised tread pattern 60a and non-contact raised tread pattern 60b. Therefore, the multiple raised tread patterns 60 are formed such that the radial end positions of the contact raised tread pattern 60a and non-contact raised tread pattern 60b are different. The raised tread pattern 60 formed in this way is formed in a shape protruding outwards from the tire. Therefore, the portion in the mold 500 for forming the raised tread pattern 60 is formed in a groove shape. Since the radial end positions of the tire are different in the contact raised tread pattern 60a and non-contact raised tread pattern 60b, the radial end positions of the tire are also different in the portion of the mold 500 where the contact raised tread pattern 60a is formed and the portion where the non-contact raised tread pattern 60b is formed. Therefore, the workability of the mold processing when forming the portion of the mold 500 for forming the raised tread pattern 60 can be improved.

[0087] In detail, when forming the portion of the mold 500 where the raised pattern 60 is formed into a groove shape, a drill bit for machining the mold 500 is used. However, since the ends of the portion forming the contact raised pattern 60a and the portion forming the non-contact raised pattern 60b in the mold 500 are at different positions, when the drill bit moves between the ends, it is possible to move the drill bit naturally while maintaining the process of groove machining along the extension direction of the raised pattern 60. This improves the workability of forming the portion of the mold 500 where the raised pattern 60 is formed and suppresses the deterioration of mold machinability caused by arranging multiple raised patterns 60 in the ridge region 50. As a result, while suppressing the deterioration of mold machinability, it is possible to suppress crack propagation and continuously maintain an aesthetically pleasing appearance.

[0088] Furthermore, the height Y of the raised pattern 60 is within ±0.80 mm relative to the height S of the smooth surface region 40. Therefore, when a crack occurs in the ridge region 50, the raised pattern 60, with its guaranteed height, can suppress crack propagation. As a result, crack propagation can be more reliably suppressed, thus maintaining a consistently aesthetic appearance.

[0089] Furthermore, regarding the raised tread pattern 60, adjacent raised tread patterns 60 are arranged parallel to each other. Therefore, not only can the aesthetics of the raised ridge area 50 be improved more reliably through the multiple raised ridges 55, but also through the multiple raised tread patterns 60. Additionally, regarding the raised tread pattern 60, since adjacent raised tread patterns 60 are arranged parallel to each other, when forming grooves for forming the raised tread pattern 60 on the tire sidewall 31 in the mold 500 using a drill bit, the drill bit can be moved in the same direction. This improves the workability when forming the portion of the raised tread pattern 60 in the mold 500 and suppresses the deterioration of mold machinability caused by arranging multiple raised tread patterns 60 in the raised ridge area 50. As a result, the aesthetic appearance is improved while suppressing the deterioration of mold machinability.

[0090] Furthermore, the spacing P of the plurality of ridges 55 disposed in the ridge region 50 is within the range of 0.55mm ≤ P ≤ 1.50mm. Therefore, when applying tire wax as a protective layer to the tire sidewall 31, for example, it can be applied appropriately. That is to say, in order to protect and polish the tire sidewall 31, tire wax is sometimes applied to the tire sidewall 31. However, when the spacing P of the plurality of ridges 55 is less than 0.55mm, it may be difficult to apply tire wax to the ridge region 50 because the spacing P is too small. On the other hand, when the spacing P of the plurality of ridges 55 is greater than 1.50mm, the tire wax may be easily peeled off when it is applied to the ridge region 50 because the spacing P is too large.

[0091] In contrast, when the spacing P of the multiple ridges 55 is within the range of 0.55mm ≤ P ≤ 1.50mm, tire wax can be applied appropriately to the ridge areas 50, and the applied tire wax is difficult to peel off. Therefore, the tire wax can be used to polish and protect the ridge areas 50, thus suppressing cracking in the ridge areas 50. As a result, the appearance is improved and can be maintained continuously.

[0092] Furthermore, regarding the plurality of ridges 55 disposed in the ridge region 50, the ratio H / B of the height H of the ridge 55 to the width B of the ridge 55 is within the range of 0.60 ≤ H / B ≤ 1.40. Therefore, when tire wax is applied to the ridge region 50, the effect of the applied tire wax can be maintained for a long period of time. That is to say, when the ratio H / B of the height H of the ridge 55 to the width B is less than 0.60, the height H is too low relative to the width B of the ridge 55. Therefore, it is not possible to protect the tire wax from external impacts when it is applied to the ridge region 50, and the tire wax may be easily peeled off. On the other hand, when the ratio H / B of the height H of the ridge 55 to the width B is greater than 1.40, the height H is too high relative to the width B of the ridge 55. Therefore, when tire wax is applied to the ridge region 50, the penetration of the tire wax into the ridges 55 becomes slower, and it may be difficult to apply tire wax efficiently to the ridge region 50.

[0093] In contrast, when the ratio of the height H to the width B of the ridge 55 is within the range of 0.60 ≤ H / B ≤ 1.40, tire wax can be applied efficiently to the ridge area 50, and the effect of the applied tire wax can be maintained for a long time. As a result, the tire wax applied to the ridge area 50 improves the appearance and can maintain its appearance continuously.

[0094] Furthermore, since the raised pattern 60 has alternating wide portions 61 and narrow portions 62 along its extension direction, when a crack generated in the ridge region 50 propagates along the raised pattern 60, the direction of crack propagation can change in a step-like manner. This suppresses the rapid propagation of cracks generated in the ridge region 50, thus preventing aesthetic deterioration. As a result, crack propagation is suppressed, and the aesthetic appearance is maintained continuously.

[0095] Furthermore, regarding the raised tread pattern 60, since the ratio d / D of the width D of the wide portion 61 to the width d of the narrow portion 62 is within the range of 0.10 ≤ d / D ≤ 0.50, it is possible to effectively improve the aesthetic appearance while suppressing vulcanization defects. In other words, when the ratio d / D of the width D of the wide portion 61 to the width d of the narrow portion 62 of the raised tread pattern 60 is d / D < 0.10, the width d of the narrow portion 62 is too narrow, making it difficult to see and potentially hindering the improvement of the aesthetic appearance. Conversely, when the ratio d / D of the width D of the wide portion 61 to the width d of the narrow portion 62 of the raised tread pattern 60 is d / D > 0.50, the width d of the narrow portion 62 is too wide, potentially making the overall volume of the raised tread pattern 60 too large. During the vulcanization molding of the pneumatic tire 1, vulcanization defects may easily occur around the raised tread pattern 60.

[0096] In contrast, when the ratio d / D of the width D of the wide portion 61 of the raised tread pattern 60 to the width d of the narrow portion 62 is within the range of 0.10 ≤ d / D ≤ 0.50, since the width d of the narrow portion 62 can be made to an appropriate size, the appearance can be effectively improved by the raised tread pattern 60 while suppressing vulcanization defects during the vulcanization molding of the pneumatic tire 1. As a result, the appearance can be improved more reliably while suppressing vulcanization defects during the manufacturing of the pneumatic tire 1.

[0097] Furthermore, regarding the plurality of raised patterns 60 disposed in the ridge region 50, since the spacing X is within the range of 1.00 mm ≤ X ≤ 5.00 mm, the incidence of vulcanization failure can be suppressed, and the propagation of cracks can be effectively suppressed by the raised patterns 60. That is, when the spacing X of the raised patterns 60 is less than 1.00 mm, the spacing X is too small, and the proximity of adjacent raised patterns 60 may lead to a higher incidence of vulcanization failure during the manufacturing of the pneumatic tire 1. Conversely, when the spacing X of the raised patterns 60 is greater than 5.00 mm, the spacing X is too large, and the proximity of adjacent raised patterns 60 may be too large, making it difficult to effectively suppress the propagation of cracks generated in the ridge region 50 by the raised patterns 60.

[0098] In contrast, when the spacing X of the multiple raised tread patterns 60 is within the range of 1.00mm ≤ X ≤ 5.00mm, the incidence of vulcanization failures caused by the arrangement of raised tread patterns 60 in the ridge region 50 can be suppressed, and the propagation of cracks generated in the ridge region 50 can be effectively suppressed by the raised tread patterns 60. As a result, vulcanization failures during the manufacturing of the pneumatic tire 1 can be suppressed, and the propagation of cracks can be suppressed to maintain a consistently aesthetic appearance.

[0099] Furthermore, regarding the multiple raised patterns 60, since the ratio D / X of the width D of the wide portion 61 of the raised pattern 60 to the spacing X of the multiple raised patterns 60 is in the range of 0.20≤D / X≤5.00, the incidence of sulfidation failure can be suppressed more effectively, and the propagation of cracks can be effectively suppressed by the raised patterns 60. That is to say, when the ratio D / X of the width D of the wide portion 61 of the raised pattern 60 to the spacing X of the raised pattern 60 is D / X<0.20, since the spacing X of the raised patterns 60 is too large, the adjacent raised patterns 60 are too far apart, and it may be difficult to effectively suppress the propagation of cracks generated in the ridge region 50 by the raised patterns 60. Furthermore, when the ratio of the width D of the wide portion 61 of the raised pattern 60 to the spacing X of the raised pattern 60, D / X, is D / X > 5.00, the spacing X of the raised pattern 60 is too small. Therefore, the occurrence rate of vulcanization failure during the manufacturing of the pneumatic tire 1 may increase because the adjacent raised patterns 60 are too close to each other.

[0100] In contrast, when the ratio D / X of the width D of the wide portion 61 of the raised pattern 60 to the spacing X of the raised pattern 60 is within the range of 0.20 ≤ D / X ≤ 5.00, the incidence of vulcanization defects caused by the arrangement of the raised pattern 60 in the ridge region 50 can be suppressed, and the propagation of cracks generated in the ridge region 50 can be effectively suppressed by the raised pattern 60. As a result, the occurrence of vulcanization defects during the manufacturing of the pneumatic tire 1 can be suppressed, and the propagation of cracks can be suppressed to maintain a consistently aesthetic appearance.

[0101] Furthermore, regarding the raised pattern 60, since the length L1 of the wide portion 61 and the length L2 of the narrow portion 62 satisfy the relationship 0.30 ≤ L1 / (L1+L2) ≤ 0.70, it is possible to prevent the area difference between the portion of the raised ridge 55 adjacent to the wide portion 61 of the raised pattern 60 and the portion adjacent to the narrow portion 62 in the raised ridge region 50 from becoming too large. Therefore, when elastic deformation occurs in the sidewall portion 30, it is possible to suppress the generation of large local stresses in the raised ridge region 50, and cracks are less likely to occur in the raised ridge region 50. As a result, the aesthetic appearance can be maintained continuously.

[0102] Furthermore, regarding the raised tread pattern 60, the wide portion 61 of one adjacent raised tread pattern 60 and the narrow portion 62 of the other raised tread pattern 60 have portions positioned at the same location relative to each other in the tire radial direction. Therefore, it is possible to prevent the area difference between the portion located between the wide portion 61 of one raised tread pattern 60 and the narrow portion 62 of the other raised tread pattern 60, and the portion located between the narrow portion 62 of one raised tread pattern 60 and the wide portion 61 of the other raised tread pattern 60, from becoming excessive. Consequently, when elastic deformation occurs in the sidewall portion 30, it is possible to suppress the generation of large localized stresses in the ridge region 50, and cracks are less likely to form in the ridge region 50. As a result, an aesthetically pleasing appearance can be maintained continuously.

[0103] [Variation Example]

[0104] Furthermore, in the above-described embodiments, the raised pattern 60 has a wide portion 61 and a narrow portion 62, but the raised pattern 60 may also not have a wide portion 61 and a narrow portion 62. Figure 8 This is a variation of the pneumatic tire 1 of the embodiment, and is an explanatory diagram showing that the raised tread pattern 60 disposed in the ridge region 50 is formed with a certain width. The raised tread pattern 60 disposed in the ridge region 50 can, for example, be as follows: Figure 8 As shown, it is formed with a certain width. The plurality of raised patterns 60 disposed in the ridge region 50 extend in a direction that intersects with the extension direction of the ridge 55, and have contact raised patterns 60a that are in contact with the outline portion 51 of the radial outer side of the tire in the ridge region 50 and non-contact raised patterns 60b that are separated from the outline portion 51 of the ridge region 50.

[0105] The plurality of raised patterns 60 disposed in the ridge region 50 extend in directions intersecting the extending directions of the ridge 55 and have contact raised patterns 60a and non-contact raised patterns 60b, which can suppress the propagation of cracks. In addition, it can suppress the deterioration of mold machinability caused by the placement of raised patterns 60 in the ridge region 50. As a result, while suppressing the deterioration of mold machinability, it is possible to suppress the propagation of cracks and continuously maintain an aesthetic appearance.

[0106] Furthermore, in the pneumatic tire 1 of the above embodiment, the two ridge regions 50 provided on the side 31 of one tire have the same shape, but the ridge regions 50 provided on the side 31 of one tire can also have different shapes. That is, regarding the ridge regions 50, the angle and spacing of the ridges 55 provided on the ridge regions 50, the angle and spacing of the raised patterns 60, the length, the size of the wide portion 61 and the narrow portion 62 of the raised patterns 60, the arrangement order of the contact raised patterns 60a and the non-contact raised patterns 60b, and the size of the ridge regions 50 can also be different.

[0107] Furthermore, in the pneumatic tire 1 of the above-described embodiment, ridge regions 50 are provided at two locations on one tire sidewall 31. However, ridge regions 50 may also be provided at more than two locations on one tire sidewall 31. For example, there may be three or more ridge regions 50 on one tire sidewall 31, or there may be only one ridge region 50 on one tire sidewall 31. When there is only one ridge region 50 on one tire sidewall 31, it may be a portion of the tire sidewall 31 in the tire circumferential direction, or the ridge region 50 may be provided throughout the entire circumference of the tire. When the ridge region 50 is provided throughout the entire circumference of the tire, and a smooth surface region 40 is also provided, the smooth surface region 40 may be located at a position different from the ridge region 50 in the tire radial direction, or it may be provided within the ridge region 50.

[0108] Furthermore, in the pneumatic tire 1 of the above-described embodiment, the smooth surface region 40 and the ridge region 50 have the same shape on both sides of the tire sidewall 31 in the tire width direction. However, the smooth surface region 40 and the ridge region 50 can also be provided with different shapes on both sides of the tire sidewall 31 in the tire width direction. By making the smooth surface region 40 and the ridge region 50 different for each tire sidewall 31, the design flexibility can be improved. In the pneumatic tire 1 with a specified vehicle assembly direction, the propagation of cracks can be further suppressed in the ridge region 50 of the tire sidewall 31 on the side prone to cracking.

[0109] Furthermore, the above-described embodiments and variations can be appropriately combined. Additionally, in the above embodiments, a pneumatic tire 1 was used as an example of the tire of the present invention, but the tire of the present invention can also be a tire other than a pneumatic tire 1. For example, the tire of the present invention can be a so-called airless tire, capable of being used without inflation.

[0110] [Example]

[0111] Figure 9 This is a graph showing the results of performance evaluation tests on the pneumatic tire. Hereinafter, performance evaluation tests conducted on the conventional pneumatic tire and the pneumatic tire 1 of the present invention will be described with reference to the aforementioned pneumatic tire 1. Regarding the performance evaluation tests, tests were conducted on mold processability, crack propagation inhibition, and aesthetics at the end of the product's lifespan.

[0112] The performance evaluation test is conducted by assembling a rim with a pneumatic tire of size 235 / 50R18 as specified by JATMA onto a JATMA standard rim wheel with a rim size of 18×7.5J.

[0113] The evaluation method for each test item was based on the cost incurred in manufacturing the formed ridge region 50 in the mold, considering mold manufacturability. The evaluation related to mold manufacturability was conducted using an index of 100, calculated as the reciprocal of the calculated cost. A higher index value indicates lower manufacturing costs for the formed ridge region 50 in the mold, signifying superior mold manufacturability. Furthermore, regarding mold manufacturability, an index of 98 or higher indicates that the same level of manufacturability can be maintained compared to previous examples, and deterioration in mold manufacturability is suppressed.

[0114] Furthermore, the evaluation test related to crack propagation inhibition was conducted as follows: An indoor drum test was performed on the test tire using a drum testing machine with a drum diameter of 600 mm. The test tire was rotated in the drum testing machine while ozone was being sprayed, thereby degrading the test tire. Then, the test tire was rotated at high speed while a load was applied in the drum testing machine. The length of the cracks generated in the ridge region 50 on the tire sidewall 31 was then measured, and the number of cracks was counted, calculating the total length of the cracks. The evaluation related to crack propagation inhibition was performed using an index evaluation, calculated as the reciprocal of the total calculated crack lengths, with the previous example set to 100 (described later). Regarding crack propagation inhibition, a higher index value indicates less crack propagation in the ridge region, and thus better crack propagation inhibition.

[0115] In addition, regarding the aesthetics at the end of the product's lifespan, road tests were conducted on vehicles with test tires coated with water-based tire wax fitted to the tire sidewall 31. The aesthetics of the test tires, after being retrieved following 4000 km of driving, were evaluated visually by evaluators. The evaluation related to the aesthetics at the end of the product's lifespan was based on visual assessment by the evaluators and was conducted using an index of 100 (as described below in the previous example). Regarding the aesthetics at the end of the product's lifespan, a higher index value indicates fewer cracks in the ridge area 50, and a better aesthetic appearance at the end of the product's lifespan.

[0116] The performance evaluation test was conducted on 14 types of pneumatic tires, including conventional pneumatic tires as examples of conventional pneumatic tires and Examples 1 to 13, which are pneumatic tires of the present invention. Among them, although the conventional pneumatic tires have ridged areas on the tire sidewalls, they do not have raised tread patterns configured in the ridged areas.

[0117] In contrast, in embodiments 1 to 13, which are examples of the pneumatic tire 1 of the present invention, all the ridge regions 50 are provided with raised patterns 60 having contact raised patterns 60a and non-contact raised patterns 60b. Moreover, regarding the pneumatic tire 1 of embodiments 1 to 13, the difference between the height Y of the raised pattern 60 and the height S of the smooth surface region 40, the spacing P of the ridges 55, the ratio H / B of the height H of the ridges 55 to the width B of the ridges 55, the presence or absence of the wide portion 61 and the narrow portion 62 of the raised pattern 60, the ratio d / D of the width D of the wide portion 61 of the raised pattern 60 to the width d of the narrow portion 62 of the raised pattern 60, the spacing X of the raised pattern 60, and the relationship L1 / (L1+L2) between the length L1 of the wide portion 61 and the length L2 of the narrow portion 62 of the raised pattern 60 are different.

[0118] The results of the evaluation tests conducted using these pneumatic tires 1 show that, as Figure 9 As shown, the pneumatic tires 1 of Examples 1-13, compared to conventional examples, can suppress the deterioration of mold processability when the raised tread pattern 60 is provided in the ridge region 50 as much as possible. Compared to conventional examples, they can improve the suppression of crack propagation in the ridge region 50 and the aesthetic appearance of the product in the later stages of its life. In other words, the pneumatic tires 1 of Examples 1-13 can suppress the deterioration of mold processability while suppressing crack propagation and continuously maintaining an aesthetic appearance.

[0119] This disclosure includes the following inventions.

[0120] Invention [1]

[0121] A tire, characterized in that it comprises:

[0122] A ridge region, formed on the tire sidewall surface, wherein multiple ridges are arranged in the ridge region; and

[0123] Multiple raised patterns are arranged in the ridge region with a height greater than the height of the ridge in the height direction of the ridge, and extend in a direction intersecting the extension direction of the ridge.

[0124] The plurality of the raised patterns have: raised patterns that are in contact with the outline portion of the tire radially outer side of the ridge region; and raised patterns that are separate from the outline portion of the ridge region.

[0125] Invention [2]

[0126] According to the tire described in invention [1],

[0127] A smooth surface region is formed on the side of the tire. The smooth surface region is a planar region whose height in the height direction of the ridge is higher than the height of the ridge.

[0128] The height of the raised pattern in the height direction of the ridge is within ±0.80 mm relative to the height of the smooth surface area.

[0129] Invention [3]

[0130] The tire according to invention [1] or invention [2],

[0131] Regarding the raised patterns, adjacent raised patterns are arranged parallel to each other.

[0132] Invention [4]

[0133] The tire according to any one of the inventions [1] to [3],

[0134] The spacing P of the plurality of ridges disposed in the ridge region is in the range of 0.55mm ≤ P ≤ 1.50mm.

[0135] The ratio H / B of the height H of the ridge to the width B of the ridge is in the range of 0.60 ≤ H / B ≤ 1.40.

[0136] Invention [5]

[0137] The tire according to any one of the inventions [1] to [4],

[0138] The raised pattern is alternately formed with wide and narrow portions in the extension direction of the raised pattern, and the width of the narrow portion in the direction intersecting the extension direction of the raised pattern is narrower than the width of the wide portion.

[0139] Invention [6]

[0140] According to the tire described in invention [5],

[0141] Regarding the raised pattern, the ratio d / D of the width D of the wide portion to the width d of the narrow portion is within the range of 0.10 ≤ d / D ≤ 0.50.

[0142] Invention [7]

[0143] According to the tire described in invention [3],

[0144] The spacing X of the plurality of raised patterns is in the range of 1.00mm≤X≤5.00mm.

[0145] Invention [8]

[0146] The tire according to invention [5] or invention [6],

[0147] Regarding the raised patterns, adjacent raised patterns are arranged parallel to each other.

[0148] Regarding the plurality of raised patterns, the ratio D / X of the width D of the wide portion to the spacing X of the plurality of raised patterns is in the range of 0.20≤D / X≤5.00.

[0149] Invention [9]

[0150] The tire according to any one of the inventions [5], [6], and [8]

[0151] Regarding the raised pattern, the length L1 of the wide portion and the length L2 of the narrow portion in the extension direction of the raised pattern satisfy the relationship 0.30≤L1 / (L1+L2)≤0.70.

[0152] Invention

[10]

[0153] The tire according to any one of the inventions [5], [6], [8], and [9]

[0154] Regarding the plurality of the tread patterns, the wide portion of one tread pattern and the narrow portion of the other tread pattern of adjacent tread patterns have portions that are located in the same position relative to each other in the tire radial direction.

[0155] Explanation of reference numerals in the attached figures

[0156] 1. Pneumatic tire

[0157] 2nd pregnancy face

[0158] 3. Tread surface

[0159] 5. Tire equatorial plane

[0160] 8. Tire shoulder

[0161] 10. Bead section

[0162] 11. Tire bead core

[0163] 12. Bead filling

[0164] 13. Fetal body

[0165] 14 Belt Layer

[0166] 15 Lining

[0167] 17. Rim cushioning rubber

[0168] 18 Turnback Section

[0169] 20. Land Forces

[0170] 25 Circumferential Main Slot

[0171] 30 Side wall portion

[0172] 31 Tire sidewall

[0173] 40 Smooth surface area

[0174] 50 convex ridge area

[0175] 51. Outline

[0176] 52. Outline

[0177] 53 Base surface

[0178] 55 Convex Ridge

[0179] 60 raised patterns

[0180] 60a Contact protrusion pattern

[0181] 60b Non-contact raised pattern

[0182] 61 Wide section

[0183] 62 Narrow section

[0184] 500 molds

[0185] 501 Fan-shaped mold

[0186] 502 side mold

Claims

1. A tire, characterized in that, have: A ridge region, formed on the tire sidewall surface, wherein multiple ridges are arranged in the ridge region; and Multiple raised patterns are arranged in the ridge region with a height greater than the height of the ridge in the height direction of the ridge, and extend in a direction intersecting the extension direction of the ridge. The plurality of the raised patterns have: raised patterns that are in contact with the outline portion of the tire radially outer side of the ridge region; and raised patterns that are separate from the outline portion of the ridge region.

2. The tire according to claim 1, A smooth surface region is formed on the side of the tire. The smooth surface region is a planar region whose height in the height direction of the ridge is higher than the height of the ridge. The height of the raised pattern in the height direction of the ridge is within ±0.80 mm relative to the height of the smooth surface area.

3. The tire according to claim 1 or 2, Regarding the raised patterns, adjacent raised patterns are arranged parallel to each other.

4. The tire according to claim 1 or 2, The spacing P of the plurality of ridges disposed in the ridge region is in the range of 0.55mm ≤ P ≤ 1.50mm. The ratio H / B of the height H of the ridge to the width B of the ridge is in the range of 0.60 ≤ H / B ≤ 1.

40.

5. The tire according to claim 1, The raised pattern is alternately formed with wide and narrow portions in the extension direction of the raised pattern, and the width of the narrow portion in the direction intersecting the extension direction of the raised pattern is narrower than the width of the wide portion.

6. The tire according to claim 5, Regarding the raised pattern, the ratio d / D of the width D of the wide portion to the width d of the narrow portion is within the range of 0.10 ≤ d / D ≤ 0.

50.

7. The tire according to claim 3, The spacing X of the plurality of raised patterns is in the range of 1.00mm≤X≤5.00mm.

8. The tire according to claim 5 or 6, Regarding the raised patterns, adjacent raised patterns are arranged parallel to each other. Regarding the plurality of raised patterns, the ratio D / X of the width D of the wide portion to the spacing X of the plurality of raised patterns is in the range of 0.20≤D / X≤5.

00.

9. The tire according to claim 5 or 6, Regarding the raised pattern, the length L1 of the wide portion and the length L2 of the narrow portion in the extension direction of the raised pattern satisfy the relationship 0.30≤L1 / (L1+L2)≤0.

70.

10. The tire according to claim 5 or 6, Regarding the plurality of the tread patterns, the wide portion of one tread pattern and the narrow portion of the other tread pattern of adjacent tread patterns have portions that are located in the same position relative to each other in the tire radial direction.

Images