pneumatic tires

Abstract

The present invention provides a pneumatic tire that effectively conceals sidewall irregularities while also suppressing the occurrence of bearing failure and improving damage resistance. [Solution] The tire sidewall is decorated with multiple ridges and has a strip-shaped first L-shaped decorative section 4 and a wavy decorative section 3 that extend in the tire circumferential direction CD. The first L-shaped decorative section 4 is positioned circumferentially inward from both ends of the wavy decorative section 3 in the tire circumferential direction. The first L-shaped decorative section 4 has a first portion 41 extending in a first direction D41 and a second portion 42 extending toward the wavy decorative section 3 along a second direction D42, which has a larger angle with respect to the tire circumferential direction CD than the first direction D41. The shortest distance between the second portion 42 and the wavy decorative section 3 is a first distance W32 of 0.5 mm or more and 3.0 mm or less. The shortest distance W31 between the first portion 41 and the wavy decorative section 3 is greater than the first distance W32.

Description

Technical Field

[0001] The present disclosure relates to pneumatic tires.

Background Art

[0002] In the sidewall of a tire, unevenness may occur in a portion corresponding to the joint part at the start and end of winding of the carcass ply, and in a portion corresponding to the folded end of the carcass ply folded back from the inside to the outside of the bead core. Local unevenness occurring in the sidewall may not affect the performance and durability of the tire, but may cause a decrease in appearance quality.

[0003] In order to make such local unevenness of the sidewall less noticeable, a pneumatic tire is disclosed in which a decorative part having a number of ridges arranged in parallel or substantially parallel at minute intervals is provided on the sidewall to camouflage the local unevenness (for example, Patent Document 1).

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Patent Document 1 discloses a pneumatic tire in which two belt-like decorative parts are formed on the sidewall. Each decorative part has a plurality of ridges. The two belt-like decorative parts extend in the tire circumferential direction and intersect. Since the two belt-like decorative parts intersect, a recessed scar in an unvulcanized state called a bare due to a lack of rubber during tire vulcanization may occur at the intersection. In addition, there is a possibility that a cut scar occurring in one decorative part extends to the other decorative part through the intersection, and an improvement in damage resistance performance is required.

[0006] This disclosure provides a pneumatic tire that effectively conceals sidewall irregularities while also suppressing the occurrence of bare tire and improving damage resistance. [Means for solving the problem]

[0007] The pneumatic tire of the present disclosure has a sidewall having an undecorated region having a smooth surface and a strip-shaped first decorative portion and a second decorative portion that are decorated with a plurality of ridges and extend in the circumferential direction of the tire, wherein the first decorative portion and the second decorative portion are surrounded by the undecorated region and have recesses that are indented relative to the smooth surface, the plurality of ridges protruding from the bottom of the recesses, the first decorative portion is positioned on the radially outer or inner side of the second decorative portion, and either the first decorative portion or the second decorative portion is positioned circumferentially inward of the tire beyond both ends of the other decorative portion in the circumferential direction of the tire, the first decorative portion has a first portion extending in a first direction and a second portion extending toward the second decorative portion along a second direction at a larger angle with respect to the circumferential direction of the tire than the first direction, the shortest distance between the second portion and the second decorative portion is a first distance of 0.5 mm or more and 3.0 mm or less, and the shortest distance between the first portion and the second decorative portion is greater than the first distance. [Brief explanation of the drawing]

[0008] [Figure 1] This figure shows a portion of the outer surface of the sidewall as viewed from the outside in the axial direction of the tire. [Figure 2] This is a diagram showing the main parts of Figure 1. [Figure 3] Figure 3(A) is a cross-sectional view taken along the arrow AA in Figure 1. Figure 3(B) is a cross-sectional view taken along the arrow BB in Figures 1 and 2. Figure 3(C) is a cross-sectional view taken along the arrow C in Figure 2. Figure 3(D) is a cross-sectional view taken along the arrow D in Figure 2. Figure 3(E) is a cross-sectional view taken along the arrow E in Figure 2. [Figure 4] This is an enlarged view showing the wavy decorative section and the first L-shaped decorative section. [Figure 5] This is an enlarged view showing the wavy decorative section, the second L-shaped decorative section, and the third L-shaped decorative section. [Figure 6] This figure shows the first L-shaped decorative part and the wavy decorative part according to the first modified example. [Figure 7] This figure shows the first L-shaped decorative part and the wavy decorative part according to the second modified example. [Figure 8] This figure shows the first L-shaped decorative part and the wavy decorative part according to the third modified example. [Figure 9] This figure shows the first L-shaped decorative part and the wavy decorative part according to the fourth modified example. [Figure 10] This figure shows the wavy decorative section, the second L-shaped decorative section, and the third L-shaped decorative section according to the fifth modified example. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of this disclosure will be described with reference to the drawings.

[0010] <Basic Tire Structure> The tire radial direction is the direction along the tire's diameter. The inner direction in the tire radial direction is the direction approaching the tire's axis of rotation. The outer direction in the tire radial direction is the direction away from the tire's axis of rotation. The tire axial direction is the direction parallel to the tire's axis of rotation. The inner direction in the tire axial direction is the direction approaching the tire's equatorial plane (not shown). The outer direction in the tire axial direction is the direction away from the tire's equatorial plane. The tire's equatorial plane is a virtual plane located at the center of the tire's axial direction and perpendicular to the tire's axis of rotation. The tire circumferential direction CD (see Figure 1) is the direction around the tire's axis of rotation.

[0011] Although not shown, a tire has a pair of beads, a pair of sidewalls 2 (see Figure 1) extending radially outward from the pair of beads, and a tread connected to the radially outer end of each sidewall 2. The tire has a carcass that extends in a toroidal shape across the pair of beads. The carcass is formed of carcass plies formed by covering carcass cords with rubber. The material used for the carcass cords is metal such as steel or organic fibers such as polyester. Sidewall rubber, which forms the outer surface of the sidewalls 2, is provided on the axially oriented side of the carcass.

[0012] <Sidewall 2> Figure 1 shows a portion of the outer surface of the sidewall 2 as viewed from the outside in the tire axial direction, specifically the region between the mold split position Ps and the circumferential protrusion 23, as viewed from the outside in the tire axial direction. The maximum tire width position Pm shown in Figure 1 is the position where the profile surface PF of the sidewall 2 is furthest from the tire equatorial plane in the tire axial direction. The profile surface PF is the surface that forms the basic contour of the sidewall 2, excluding protrusions such as ridges. The profile surface PF is formed by a smooth curved surface that is convex in the direction outward in the tire axial direction. When viewed in the tire meridian cross-section, the profile surface PF is composed of multiple curved surfaces with different curvatures in the tire radial direction.

[0013] As shown in Figure 1, the mold splitting position Ps is located radially outward from the tire's maximum width position Pm. The mold splitting position Ps is the boundary (splitting position) between the tread mold that forms the tread and the side mold that forms the sidewall 2. The mold splitting position Ps can also be identified by the parting line that forms on the outer surface of the sidewall 2. The parting line is a protruding mold mark that forms at the splitting position.

[0014] The rim line not shown is disposed radially inward of the tire diameter from the tire maximum width position Pm. The rim line is formed by protrusions extending annularly along the tire circumferential direction CD. The rim line is used to confirm that the bead is correctly mounted on the rim when the tire is assembled to the wheel. Although not shown in FIG. 1, in the present embodiment, between the mold parting position Ps and the rim line, three circumferential protrusions 21, 22, 23 protruding outward in the tire axial direction are arranged in order from the outside in the tire radial direction toward the inside in the tire radial direction.

[0015] FIG. 2 is a view showing a main part of FIG. 1. FIG. 3(A) is a cross-sectional view taken along the line A-A in FIG. 1, showing a cross-section along a direction orthogonal to the extending direction of the ridge 71 of the logo 1. FIG. 3(B) is a cross-sectional view taken along the line B-B in FIGS. 1 and 2, and is a cross-sectional view of the undecorated area BR having a smooth surface without the ridge 71. FIG. 3(C) is a cross-sectional view taken along the line C in FIG. 2, showing a cross-section passing through the valley portion between the ridges 71 along a direction parallel to the extending direction of the ridge 71. FIG. 3(D) is a cross-sectional view taken along the line D in FIG. 2, showing a cross-section along a direction intersecting the extending direction of the ridge 71. FIG. 3(E) is a cross-sectional view taken along the line E-E in FIG. 2, showing a cross-section passing through the top of the ridge 71 along a direction parallel to the extending direction of the ridge 71.

[0016] As shown in FIGS. 1 to 2, in this tire, on the outer surface of at least one of the pair of sidewalls 2, a belt-shaped undecorated area BR extending in the tire circumferential direction CD and a plurality of decorative parts (3, 4, 5, 6) are arranged. The undecorated area BR is a region having a smooth surface (profile surface PF) without the ridge 71, as shown in FIG. 3(B). The undecorated area BR is provided between the circumferential protrusion 21 and the circumferential protrusion 22, as shown in FIGS. 1 and 2. The undecorated area BR has a constant width and is provided as an annular region extending over the entire circumference of the tire circumferential direction CD. The undecorated area BR is formed in a certain region in the tire radial direction including the tire maximum width position Pm.

[0017] As shown in FIGS. 1 and 2, the plurality of decorative portions in the present embodiment include a wavy decorative portion 3, a first L-shaped decorative portion 4, a second L-shaped decorative portion 5, and a third L-shaped decorative portion 6. As shown in FIGS. 2 and 3, the plurality of decorative portions (3, 4, 5, 6) are decorated with a plurality of ridges 71 and are formed in a strip shape extending in the tire circumferential direction CD. As shown in FIGS. 3(C), FIGS. 3(D), and FIGS. 3(E), the plurality of decorative portions (3, 4, 5, 6) are respectively disposed in recesses 70 recessed inward in the tire axial direction with respect to the profile surface PF of the sidewall 2, and a plurality of ridges 71 protrude from the bottom of the recesses 70. The plurality of decorative portions (3, 4, 5, 6) are respectively surrounded by an undecorated region BR.

[0018] As shown in FIG. 1, the undecorated region BR has a logo 1. The logo 1 is composed of a logo such as characters, numbers, symbols, or figures, and displays information such as tire size, manufacturer name, and variety. On the other hand, the decorative portions (3, 4, 5, 6) are composed of decorative figures, patterns, etc. and do not include the above information. As shown in FIGS. 1 and 3(A), the logo 1 is formed by a logo recess 10, and a plurality of logo ridges 11 are formed inside the logo recess 10. The top of the logo ridge 11 does not protrude from the profile surface PF, and the height of the logo ridge 11 is smaller than the depth of the logo recess 10. The depth of the logo recess 10 may be, for example, 0.5 mm or more and 2.0 mm or less. The preferred depth of the logo recess 10 is 0.5 mm. The height of the logo ridge 11 may be, for example, 0.3 mm or more and 1.0 mm or less. The preferred height of the logo ridge 11 is 0.3 mm.

[0019] As shown in FIG. 1, the undecorated region BR has a first region AR1 in which the logo 1 is formed and the decorative portion is not formed, and a second region AR2 in which the logo 1 is not formed and the decorative portion is formed. The position of the first region AR1 in the tire circumferential direction CD is different from the position of the second region AR2 in the tire circumferential direction CD and they do not overlap each other.

[0020] As shown in Figures 3(C), 3(D), and 3(E), the recess 70 has a depth D70 relative to the profile surface PF. The ridge 71 rises outward from the bottom surface of the recess 70 in the tire axial direction. By composing the decorative part with the recess 70 and the ridge 71 protruding from the recess 70, it is easier to balance the weight of the tire, and it is possible to suppress the occurrence of cracks compared to a convex-shaped decorative part in which the ridge is raised from the profile surface PF. The ridge 71 has a height H71 from the bottom to the top of the recess 70. The height H71 is set to be substantially constant along the direction of extension of the ridge 71. The height H71 of the ridge 71 is greater than the depth D70 of the recess 70 (i.e., H71 > D70), and the difference between them corresponds to the projection height Ph. The projection height Ph is the height of the ridge 71 relative to the profile surface PF. In other words, the ridge 71 protrudes beyond the profile surface PF. As a result, objects that could cause cuts are more likely to hit the ridge 71, which protrudes beyond the profile surface PF, before the profile surface PF is damaged, thus improving the scratch resistance of the profile surface PF.

[0021] The protruding height Ph of the ridge 71, the depth D70 of the recess 70, and the height H71 of the ridge 71 are common to multiple decorative parts (3, 4, 5, 6). The depth D70 is, for example, 0.3 mm or more and 0.8 mm or less. The height H71 of the ridge 71 is, for example, 0.3 mm or more and 0.9 mm or less. The pitch of the ridge 71 is, for example, 0.8 mm or more and 1.2 mm or less. The protruding height Ph is, for example, 0.05 mm or more and 1.0 mm or less. It is preferable that the pitch of the ridge 71 in one of the multiple decorative parts is different from the pitch of the ridge 71 in another of the multiple decorative parts. It is preferable that there are two or more and three or fewer types of pitch to improve the effect of concealing the irregularities of the sidewall 2.

[0022] As shown in Figure 2, the direction in which the ridges 71 of the wavy decorative section 3 extend is different from the direction in which the ridges 71 of the first L-shaped decorative section 4 extend. Furthermore, the direction in which the ridges 71 of the second L-shaped decorative section 5 and the third L-shaped decorative section 6 extend is different from the direction in which the ridges 71 of the wavy decorative section 3 extend. In addition, the direction in which the ridges 71 of the first L-shaped decorative section 4 extend is different from the direction in which at least one of the ridges 71 of the second L-shaped decorative section 5 and the third L-shaped decorative section 6 extend. By making the tire surface more complex by varying the direction in which the ridges 71 extend, and thus making it easier to disperse the viewer's gaze, the effect of concealing the irregularities of the sidewall 2 is further enhanced.

[0023] As shown in Figure 2, the wavy decorative section 3 has a first parallel extending portion 30 and a second parallel extending portion 31 that extend parallel to the tire circumferential direction CD, and a connecting extending portion 32 that connects the first parallel extending portion 30 and the second parallel extending portion 31. The first parallel extending portion 30 is positioned radially outward from the second parallel extending portion 31. The wavy decorative section 3 has a single unit in which the first parallel extending portion 30, the connecting extending portion 32, the second parallel extending portion 31, and the connecting extending portion 32 are arranged in that order from one side to the other in the tire circumferential direction CD, and one unit is repeated one or more times, thereby forming a wavy shape that extends in the tire circumferential direction CD. Furthermore, the wavy decorative portion 3 can be described as being formed in a wave-like shape extending along the tire circumferential direction CD by alternately arranging a first connecting extension portion 32 that extends from the inside to the outside in the tire radial direction toward the other side of the tire circumferential direction CD, and a second connecting extension portion 32 that extends from the outside to the inside in the tire radial direction toward the other side of the tire circumferential direction CD.

[0024] As shown in Figure 2, each of the multiple decorative parts (first L-shaped decorative part 4, second L-shaped decorative part 5, and third L-shaped decorative part 6) is positioned inward in the tire circumferential direction of the wavy decorative part 3 from both ends 3a and 3b in the tire circumferential direction CD. Here, "inward in the tire circumferential direction" refers to the direction approaching the center of the tire circumferential direction CD of the reference wavy decorative part 3. Each of the multiple decorative parts (first L-shaped decorative part 4, second L-shaped decorative part 5, and third L-shaped decorative part 6) is shorter than the length of the wavy decorative part 3 along the tire circumferential direction CD.

[0025] As shown in Figure 1, the number of decorative parts (first L-shaped decorative part 4, second L-shaped decorative part 5) positioned radially inward from the tire's maximum width position Pm (four around the entire circumference of the tire in the example in Figure 1) is greater than the number of decorative parts (third L-shaped decorative part 6) positioned radially outward from the tire's maximum width position Pm (two around the entire circumference of the tire in the example in Figure 1).

[0026] <Relationship between the first L-shaped decorative part 4 and the wavy decorative part 3> Figure 4 is an enlarged view showing the wavy decorative section 3 and the first L-shaped decorative section 4. The ridges are not shown in Figure 4. As shown in Figure 4, the first L-shaped decorative section 4 is located on the inside of the wavy decorative section 3 in the tire radial direction. The first L-shaped decorative section 4 has a first portion 41 extending in a first direction D41 and a second portion 42 extending toward the wavy decorative section 3 along a second direction D42. The first portion 41 of the first L-shaped decorative section 4 is a portion with a constant width along the tire radial direction. The first direction D41 is parallel to the tire circumferential direction CD. Also, the first edge 41a on the outside of the first portion 41 in the tire radial direction (the edge located on the side of the wavy decorative section 3) and the second edge 41b on the inside of the first portion 41 in the tire radial direction (the edge located on the opposite side of the wavy decorative section 3) are parallel to each other. Therefore, the first direction D41 can also be said to be the direction parallel to the bisector of the first edge 41a and the second edge 41b. Furthermore, the first edge 41a is parallel to the inner edge 30a of the nearest wavy decorative part 3 in the tire radial direction, and the shortest distance W31 between the first edge 41a of the first part 41 of the first L-shaped decorative part 4 and the edge 30a of the wavy decorative part 3 is constant. Preferably, the shortest distance W31 is twice or more the first distance W32 described later.

[0027] As shown in Figure 4, the end of the second portion 42 of the first L-shaped decorative part 4 has two opposing straight lines 42a and 42b. The second direction D42 is parallel to the bisectors of the two straight lines 42a and 42b. The angle of the second direction D42 with respect to the tire circumferential direction CD is larger than that of the first direction D41. The second portion 42 includes a portion located on the side of the wavy decorative part 3 than the virtual extension line L1 of the first edge 41a. The shortest distance between the second portion 42 and the wavy decorative part 3 is set to a first distance W32 of 0.5 mm or more and 3.0 mm or less. By separating the first portion 41 of the first L-shaped decorative part 4 and the wavy decorative part 3 by 0.5 mm or more in this way, the rubber flow during tire vulcanization is improved and the occurrence of bares due to insufficient rubber can be suppressed. Furthermore, by separating the first portion 41 of the first L-shaped decorative part 4 and the wavy decorative part 3 by 0.5 mm or more, it is possible to suppress the extension of a cut mark occurring on either the first L-shaped decorative part 4 or the wavy decorative part 3 to the other. In addition, by making the shortest distance between the first portion 41 of the first L-shaped decorative part 4 and the wavy decorative part 3 3.0 mm or less, the decorative part can appropriately conceal the irregularities of the sidewall 2.

[0028] <Relationship between the second L-shaped decorative part 5 and the wavy decorative part 3> Figure 5 is an enlarged view showing the wavy decorative section 3, the second L-shaped decorative section 5, and the third L-shaped decorative section 6. The ridges are not shown in Figure 5. As shown in Figure 5, the second L-shaped decorative section 5 is located on the inside of the wavy decorative section 3 in the tire radial direction. The second L-shaped decorative section 5 has a first portion 41 extending in a first direction D41 and a second portion 42 extending toward the wavy decorative section 3 along a second direction D42. The first portion 41 of the second L-shaped decorative section 5 is a portion with a constant width along the tire radial direction. The first direction D41 is parallel to the tire circumferential direction CD. Also, the first edge 41a on the outside of the first portion 41 in the tire radial direction (the edge located on the side of the wavy decorative section 3) and the second edge 41b on the inside of the first portion 41 in the tire radial direction (the edge located on the opposite side of the wavy decorative section 3) are parallel to each other. Therefore, the first direction D41 can also be said to be the direction parallel to the bisector of the first edge 41a and the second edge 41b. Furthermore, the first edge 41a is parallel to the inner edge 30a in the tire radial direction of the nearest wavy decorative part 3, and the shortest distance W31 between the first edge 41a of the first part 41 of the second L-shaped decorative part 5 and the edge 30a of the wavy decorative part 3 is constant. Preferably, the shortest distance W31 is twice or more the first distance W32 described later.

[0029] As shown in Figure 5, the end of the second portion 42 of the second L-shaped decorative part 5 has two opposing straight lines 42a and 42b. The second direction D42 is parallel to the bisectors of the two straight lines 42a and 42b. The angle of the second direction D42 with respect to the tire circumferential direction CD is larger than that of the first direction D41. The second portion 42 includes a portion located on the side of the wavy decorative part 3 than the virtual extension line L1 of the first edge 41a. The shortest distance between the second portion 42 and the wavy decorative part 3 is set to a first distance W32 that is 0.5 mm or more and 3.0 mm or less.

[0030] <Relationship between the third L-shaped decorative part 6 and the wavy decorative part 3> As shown in Figure 5, the third L-shaped decorative part 6 is positioned on the outer side of the wavy decorative part 3 in the tire radial direction. The third L-shaped decorative part 6 has a first portion 41 extending in a first direction D41 and a second portion 42 extending toward the wavy decorative part 3 along a second direction D42. The first portion 41 of the third L-shaped decorative part 6 is a portion with a constant width along the tire radial direction. The first direction D41 is parallel to the tire circumferential direction CD. Also, the first edge 41a on the outer side of the first portion 41 in the tire radial direction (the edge located on the side of the wavy decorative part 3) and the second edge 41b on the inner side of the first portion 41 in the tire radial direction (the edge located on the opposite side of the wavy decorative part 3) are parallel to each other. Therefore, the first direction D41 can also be said to be the direction parallel to the bisector of the first edge 41a and the second edge 41b. Furthermore, the first edge 41a is parallel to the inner edge 30a of the nearest wavy decorative part 3 in the tire radial direction, and the shortest distance W31 between the first edge 41a of the first portion 41 of the third L-shaped decorative part 6 and the edge 30a of the wavy decorative part 3 is constant. Preferably, the shortest distance W31 is twice or more the first distance W32 described later.

[0031] As shown in Figure 5, the end of the second portion 42 of the third L-shaped decorative part 6 has two opposing straight lines 42a and 42b. The second direction D42 is parallel to the bisectors of the two straight lines 42a and 42b. The angle of the second direction D42 with respect to the tire circumferential direction CD is larger than that of the first direction D41. The second portion 42 includes a portion located on the side of the wavy decorative part 3 than the virtual extension line L1 of the first edge 41a. The shortest distance between the second portion 42 and the wavy decorative part 3 is set to a first distance W32 that is 0.5 mm or more and 3.0 mm or less.

[0032] <Relationship between the second L-shaped decorative part 5 and the third L-shaped decorative part 6> As shown in Figure 5, the second L-shaped decorative section 5 and the third L-shaped decorative section 6 are positioned on either side of the wavy decorative section 3, forming a pair. The position on either side of the wavy decorative section 3 can be, for example, as follows: If there are two opposing straight lines 42a and 42b at the end of either the second L-shaped decorative section 5 or the third L-shaped decorative section 6 (the second L-shaped decorative section 5), then either the virtual extension line L2 of the two straight lines 42a and 42b of the second L-shaped decorative section 5 may overlap with the other of the second L-shaped decorative section 5 or the third L-shaped decorative section 6 (the third L-shaped decorative section 6). Thus, if the second L-shaped decorative section 5 and the third L-shaped decorative section 6 are positioned so as to sandwich the wavy decorative section 3 from each other, it is possible to provide a decorative section that is visible in an X shape, and the effect of concealing the unevenness of the side wall 2 can be appropriately achieved.

[0033] [Differentiation] (A) In the above embodiment, the height of the trademark ridge 11 is less than the depth of the trademark recess 10, but is not limited thereto.

[0034] (B) In the above embodiment, the height H71 of the ridge 71 is greater than the depth D70 of the recess 70 (i.e., H71 > D70), but is not limited to this. For example, H71 = D70, or H71 <D70でもよい。

[0035] (C) In the above embodiment, the ridges of the multiple decorative parts (3, 4, 5, 6) extend in different directions, but they may be the same.

[0036] (D) In ​​the above embodiment, the shortest distance W31 between the first edge 41a of the first portion 41 of the first L-shaped decorative portion 4 and the edge 30a of the wavy decorative portion 3 is constant, but is not limited to this. For example, the first portion 41 may be configured as shown in Figure 6. Figure 6 is a diagram showing the first L-shaped decorative portion 4 and the wavy decorative portion 3 according to the first modified example. In Figure 6, the ridge is not shown. As shown in Figure 6, the first edge 41a and the second edge 41b of the first portion 41 of the first L-shaped decorative portion 4 are parallel to each other, and the first portion 41 is a portion with a constant width. However, the first direction D41 is not parallel to the tire circumferential direction CD. The first direction D41 is a direction parallel to the bisector of the first edge 41a and the second edge 41b. The shortest distance W31 between the first portion 41 and the wavy decorative portion 3 is measured from the end of the first edge 41a.

[0037] (E) In the above embodiment, the first edge 41a and the second edge 41b of the first portion 41 are parallel to each other, but are not limited to this. For example, the first portion 41 may be configured as shown in Figure 7. Figure 7 shows the first L-shaped decorative portion 4 and the wavy decorative portion 3 according to the second modified example. In Figure 7, the ridge is not shown. As shown in Figure 7, if the first edge 41a and the second edge 41b of the first portion 41 of the first L-shaped decorative portion 4 are two straight lines, the first direction D41 may be the direction parallel to the bisector of the straight first edge 41a and the straight second edge 41b.

[0038] (F) In the above embodiment, the first L-shaped decorative part 4 as the first decorative part has a second portion 42, and the second portion 42 extends toward the wavy decorative part 3 as the second decorative part, but is not limited thereto. For example, as shown in Figure 8, the wavy decorative part 3 may be provided with a first portion 41 and a second portion 42. Figure 8 is a diagram showing the first L-shaped decorative part 4 and the wavy decorative part 3 according to the third modified example. The ridge is not shown in Figure 8. As shown in Figure 8, the wavy decorative section 3 has a first portion 41 extending in a first direction D41 and a second portion 42 extending toward the first L-shaped decorative section 4 along a second direction D42. The first edge 41a on the inner side of the first portion 41 in the tire radial direction (the edge located on the side of the first L-shaped decorative section 4) and the second edge 41b on the outer side of the first portion 41 in the tire radial direction (the edge located on the opposite side of the first L-shaped decorative section 4) are parallel to each other. Therefore, the first direction D41 can also be said to be the direction parallel to the bisector of the first edge 41a and the second edge 41b. Furthermore, the first edge 41a is parallel to the outer edge 30a of the nearest first L-shaped decorative section 4 in the tire radial direction, and the shortest distance W31 between the first edge 41a of the first portion 41 of the wavy decorative section 3 and the edge 30a of the first L-shaped decorative section 4 is constant. The shortest distance W31 is preferably at least twice the first distance W32, which will be described later. The second portion 42 of the wavy decorative portion 3 has a straight line 42a that is closest to the first L-shaped decorative portion 4 and a straight line 42b that is opposite to the straight line 42a. The second direction D42 is parallel to the angle bisectors of the two straight lines 42a and 42b. The second portion 42 includes a portion that is located on the side of the first L-shaped decorative portion 4 than the virtual extension line L1 of the first edge 41a.

[0039] (G) In the above embodiment, the second direction D42 of the second portion 42 of the first L-shaped decorative part 4, the second L-shaped decorative part 5, and the third L-shaped decorative part 6 is described as being parallel to the angle bisectors of two straight lines 42a and 42b facing each other at the end of the second portion 42, but is not limited to this. It may be determined as shown in Figure 9. Figure 9 shows the first L-shaped decorative part 4 and the wavy decorative part 3 according to the fourth modified example. The ridge is not shown in Figure 9. As shown in Figure 9, if there are no two straight lines at the end of the second portion 42 of the first L-shaped decorative part 4, and one is a curve 42c and the other is a straight line 42d, a perpendicular line can be drawn from the end of the straight line 42c to the straight line 42d, and the angle bisector of that perpendicular line can be set as the second direction D42.

[0040] (H) In the above embodiment, the position between the wavy decorative part 3 may be as shown in Figure 10. Figure 10 is a diagram showing the wavy decorative part 3, the second L-shaped decorative part 5, and the third L-shaped decorative part 6 according to the fifth modified example. The ridge is not shown in Figure 10. As shown in Figure 10, if one of the second L-shaped decorative part 5 and the third L-shaped decorative part 6 (the second L-shaped decorative part 5) has one end that is a curve 42c and the other end that is a straight line 42d, then the other of the second L-shaped decorative part 5 and the third L-shaped decorative part 6 (the third L-shaped decorative part 6) may overlap with either the virtual extension line L2 of the straight line 42d or the virtual straight line L3 (a straight line parallel to the virtual extension line L2 and passing through the end of the curve 42c).

[0041] Those skilled in the art will understand that the embodiments described above are specific examples of the following embodiments.

[0042] [1] As in the above embodiment, the pneumatic tire has a sidewall having an undecorated region having a smooth surface and a strip-shaped first decorative portion and a second decorative portion decorated with a plurality of ridges and extending in the circumferential direction of the tire, wherein the first decorative portion and the second decorative portion are surrounded by the undecorated region and have recesses that are indented relative to the smooth surface, the plurality of ridges protruding from the bottom of the recesses, the first decorative portion is positioned on the radially outer or inner side of the second decorative portion, and either the first decorative portion or the second decorative portion is positioned inward in the circumferential direction of the tire beyond both ends of the other decorative portion in the circumferential direction of the tire, the first decorative portion has a first portion extending in a first direction and a second portion extending toward the second decorative portion along a second direction at a larger angle with respect to the circumferential direction of the tire than the first direction, the shortest distance between the second portion and the second decorative portion is a first distance of 0.5 mm or more and 3.0 mm or less, and the shortest distance between the first portion and the second decorative portion may be greater than the first distance. Thus, since there is a gap of a distance of 1 or more at the intersection of the first decorative part having a ridge and the second decorative part, the rubber flow during tire vulcanization is improved compared to the case where there is no gap at the intersection, and the occurrence of bare rubber due to insufficient rubber can be suppressed. Furthermore, since a gap is provided between the first decorative part and the second decorative part, even if a cut scratch occurs on the first or second decorative part, it is possible to prevent the cut scratch from extending along it, thereby improving damage resistance. Furthermore, since the gap at the intersection of the first decorative part and the second decorative part is 3.0 mm or less, the first and second decorative parts can effectively conceal the unevenness of the sidewall.

[0043] [2] The pneumatic tire described in [1] above may be such that the shortest distance between the first part and the second decorative part is at least twice the first distance. This configuration allows for an appropriate separation between the first part and the second decorative part, effectively concealing the unevenness of the sidewall.

[0044] [3] The pneumatic tire described in [1] or [2] above, wherein the first decorative part is positioned further inward in the tire circumferential direction than both ends of the second decorative part in the tire circumferential direction. This configuration makes it possible to provide a design in which a first decorative section, which is relatively short in the circumferential direction of the tire, intersects with a second decorative section, which is relatively long in the circumferential direction of the tire.

[0045] [4] A pneumatic tire as described in any of [1] to [3] above, wherein the first portion is a portion with a constant width along the radial direction of the tire and has a first edge located on the side of the second decorative portion, and the second portion includes a portion located on the side of the second decorative portion that is greater than the virtual extension line of the first edge. This configuration makes it possible to provide a design that curves and extends from a first strip-shaped section, which has a constant width along the tire's radial direction and extends in the circumferential direction of the tire, to a second decorative section.

[0046] [5] A pneumatic tire as described in any of [1] to [4] above, wherein the first portion has a first edge such that the shortest distance between it and the second decorative portion is constant, and the second portion includes a portion located on the side of the second decorative portion that is greater than the virtual extension line of the first edge. This configuration makes it possible to provide a design in which a first part, separated from the second decorative part by a certain distance, curves and extends toward the second decorative part.

[0047] [6] A pneumatic tire as described in any of [1] to [5] above, wherein the tops of the ridges of the first decorative part and the second decorative part each protrude beyond the smooth surface. With this configuration, objects that could cause cuts are more likely to hit the protruding ridges before the smooth surface, thus reducing the likelihood of scratches on the smooth surface and improving its resistance to external damage.

[0048] [7] A pneumatic tire as described in any of [1] to [6] above, wherein the direction in which the ridge of the first decorative part extends is different from the direction in which the ridge of the second decorative part extends. This configuration makes it easier to conceal the unevenness of the sidewalls.

[0049] [8] A pneumatic tire according to any of [1] to [7] above, wherein at least one of the first decorative portion and the second decorative portion is formed in a wavy shape extending in the tire circumferential direction, by alternately arranging a first connecting extension portion that extends from the inside to the outside in the tire radial direction toward the other from one side in the tire circumferential direction and a second connecting extension portion that extends from the outside to the inside in the tire radial direction toward the other from one side in the tire circumferential direction. This configuration makes it possible to provide a new decorative element with a wavy design that extends in the circumferential direction of the tire in the undecorated area.

[0050] [9] A pneumatic tire as described in any of [1] to [8] above, wherein the first decorative portion is positioned inward in the tire circumferential direction from both ends of the second decorative portion in the tire circumferential direction, and the number of first decorative portions positioned inward in the tire radial direction from the tire maximum width position is greater than the number of first decorative portions positioned outward in the tire radial direction from the tire maximum width position. With this configuration, the rolled-up ends of the carcass ply are often positioned radially inward from the tire's maximum width. In response to this, the number of first decorative parts positioned radially inward is relatively increased, making it easier to conceal the irregularities in the sidewall.

[0051] Although embodiments of this disclosure have been described above with reference to the drawings, it should be understood that the specific configurations are not limited to these embodiments. The scope of this disclosure is indicated not only by the description of the embodiments above but also by the claims, and further includes all modifications within the meaning and scope equivalent to the claims.

[0052] The structures adopted in each of the above embodiments can be adopted in any other embodiment. The specific configuration of each part is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of this disclosure. [Explanation of symbols]

[0053] 2: Sidewall 3: Wavy decorative section (second decorative section) 3a, 3b: both ends 30a: Edge 32: Connection extension part 4: First L-shaped decorative part (first decorative part) 41: Part 1 41a: First edge 42:Second part 5: 2nd L-shaped decorative part (1st decorative part) 6: Third L-shaped decorative part (first decorative part) 70: recess 71: Ridge BR: Undecorated area CD: Tire circumferential direction D41: 1st direction D42 :Second direction L1: Virtual extension line L2: Virtual extension line PF: Profile surface (smooth surface) Pm: Tire maximum width position W31: Shortest distance W32: 1st distance

Claims

1. The sidewall comprises an undecorated region having a smooth surface, and a strip-shaped first decorative portion and a second decorative portion that are decorated with a plurality of ridges and extend in the circumferential direction of the tire. The first and second decorative portions are surrounded by the undecorated region and have recesses that are indented relative to the smooth surface, and the plurality of ridges protrude from the bottom of the recesses. The first decorative part is positioned on the outer or inner side of the second decorative part in the tire radial direction. Either the first decorative part or the second decorative part is positioned inward in the tire circumferential direction from both ends of the other decorative part in the tire circumferential direction. The first decorative part has a first portion extending in a first direction and a second portion extending toward the second decorative part along a second direction having a larger angle with respect to the tire circumferential direction than the first direction. The shortest distance between the second part and the second decorative part is a first distance of 0.5 mm or more and 3.0 mm or less. A pneumatic tire in which the shortest distance between the first part and the second decorative part is greater than the first distance.

2. The pneumatic tire according to claim 1, wherein the shortest distance between the first portion and the second decorative portion is at least twice the first distance.

3. The pneumatic tire according to claim 1, wherein the first decorative portion is positioned inward in the tire circumferential direction from both ends of the second decorative portion in the tire circumferential direction.

4. The first portion is a portion with a constant width along the tire diameter direction and has a first edge located on the side of the second decorative portion. The pneumatic tire according to claim 1, wherein the second portion includes a portion located on the side of the second decorative portion that is greater than the virtual extension line of the first edge.

5. The first portion has a first edge such that the shortest distance between it and the second decorative portion is constant. The pneumatic tire according to claim 1, wherein the second portion includes a portion located on the side of the second decorative portion that is greater than the virtual extension line of the first edge.

6. The pneumatic tire according to claim 1, wherein the tops of the ridges of the first and second decorative parts each protrude beyond the smooth surface.

7. The pneumatic tire according to claim 1, wherein the direction in which the ridge of the first decorative part extends is different from the direction in which the ridge of the second decorative part extends.

8. The pneumatic tire according to any one of claims 1 to 7, wherein at least one of the first decorative portion and the second decorative portion is formed in a corrugated shape extending in the tire circumferential direction, by alternately arranging a first connecting extension portion extending from the inside to the outside in the tire radial direction from one side in the tire circumferential direction to the other side, and a second connecting extension portion extending from the outside to the inside in the tire radial direction from one side in the tire circumferential direction to the other side.

9. The first decorative part is positioned inward in the tire circumferential direction from both ends of the second decorative part in the tire circumferential direction. The pneumatic tire according to any one of claims 1 to 7, wherein the number of first decorative parts arranged inward in the tire radial direction from the tire's maximum width position is greater than the number of first decorative parts arranged outward in the tire radial direction from the tire's maximum width position.

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