PNEUMATIC TIRE

Abstract

Pneumatic tire which has: a decorative area (11) on a side wall surface (10); and a first reference surface (21) and a plurality of projections (30, 330) projecting from the first reference surface (21) on the decorative area (11), wherein each of the projections (30, 330) has a projecting surface (31, 331) provided at a higher position than the first reference surface (21) and having predetermined lengths in a first direction and a second direction, and has slopes (32, 332), the slopes (32, 332) extending from the projecting surface (31, 331) to the first reference surface (21) on both sides in the second direction, the projecting surface (31, 331) being interposed therebetween, while the slopes (32, 332) are inclined with respect to the first reference surface (21), wherein a length of the projecting surface (31, 331) in the first direction is shorter than a length of the projection (30, 330) in the second direction, wherein a plurality of projection lines (23, 123, 223) are formed, in each of which the plurality of projections (30, 330) are arranged in the second direction, and positions of the projections (30, 330) are arranged shifted in the second direction in the mutually adjacent projection lines (23, 123, 223), wherein at least one of the first direction and the second direction is a non-contact arrangement direction in which gaps (24, 25, 124a, 124b, 224a, 224b, 224c) are provided between the projections (30, 330), and wherein the projecting surface (31, 331) is inclined with respect to the first reference surface (21).

Description

[Technical Field]The present invention relates to a pneumatic tire.[Prior Art]A pneumatic tire having a pattern on the sidewall as described in, for example, JP 2003 / 175707 A is known. Most prior art patterns are formed by the arrangement of many ribs which extend in straight lines at equal distances. Such a pattern increases the shapeability of the surface of the side wall.EP 2 127 911 A1 discloses a pneumatic tire having turbulence generating protrusions on a tire surface, each of the turbulence generating protrusions having a sharp edge portion. In this pneumatic tire, the following relationships are satisfied: and 1.0 ≤ p / H ≤ 50.0 and 0.1 ≤ H / e ≤ 3.0 and 1.0 ≤ L / H ≤ 50.0 and 1.0 ≤ (p-w) / w ≤ 100.0, wherein the pure tire radius is the H is a maximum height protrusion, the p is a circumferential direction protrusion, the e is a radial direction protrusion, the L is a radial direction protrusion length, and the A is a circumferential direction protrusion length.EP 2 960 081 A1 discloses a pneumatic tire having a tread portion; tire side portions and a carcass portion extending over the tread portion, the tire side portions and bead portions. The carcass portion includes a carcass body portion and folded portions each folded around a bead core. A circumferentially recessed portion that is recessed inward in the tire width direction and that extends in the tire circumferential direction is formed on the outer surface of the tire side portion, and turbulence generating protrusions are provided on the circumferentially recessed portion.[Summary of the Invention][Object to be Achieved by Invention]Incidentally, fine patterns have already been widely proposed, but an innovative pattern producing novel optical effects has not yet been widely proposed.In view of the above, it is an object of the present invention to provide a pneumatic tire with which new optical effects can be produced.[Means for Achieving Object]According to an aspect of the invention, there is provided a pneumatic tire including a decorative portion on a sidewall surface, a first reference surface, and a plurality of protrusions protruding from the first reference surface on the decorative portion, each of the protrusions having a protruding surface provided at a position higher than the first reference surface and having predetermined lengths in a first direction and a second direction, and slopes, the slopes extending from the protruding surface to the first reference surface on both sides in the second direction, the protruding surface being interposed therebetween while the slopes are inclined with respect to the first reference surface, a length of the protruding surface in the first direction being shorter than a length of the protrusion in the second direction, wherein a plurality of protrusion lines, in each of which the plurality of protrusions are arranged in the second direction, and positions of the protrusions in the second direction are arranged adjacently in the protrusion lines are formed, at least one of the first direction and the second direction is a non-contact arrangement direction in which gaps are provided between the protrusions, and the protruding surface is inclined with respect to the first reference surface.[Advantage of the Invention]In the pneumatic tire according to this embodiment, the reflection of the light on the projected surfaces, slopes and gaps produces new optical effects.[Brief Description of Drawings]FIG. 1 is a half cross-sectional view of a pneumatic tire in an axial direction.FIG. 2 is a view of a decorative portion on a sidewall surface viewed from the axial direction of the tire.Figure 3 is a perspective view of a portion of a pattern useful for understanding the invention.FIG. 4 is a cross-sectional view of the pattern in a circumferential direction of the tire.FIG. 5 is a view of the pattern viewed from a direction perpendicular to a first reference surface.FIG. 6 is a view of a pattern according to a modification example, taken from the direction perpendicular to the first reference surface, which is a view having long and short gaps.FIG. 7 is a view of a pattern including three kinds of gaps having different lengths from the direction perpendicular to the first reference surface according to a modification example.FIG. 8 is a perspective view of protrusions according to an example of the present invention, in which a protruding surface of the protrusion is inclined with respect to the first reference surface.FIG. 9 is a cross-sectional view of a pattern in the circumferential direction of the tire according to a modification example showing an example in which the protruding surfaces of the protrusions are lower than a second reference surface.FIG. 10 is a cross-sectional view of a pattern in the circumferential direction of the tire according to a modification example showing an example in which the first reference surface is higher than the second reference surface.[Mode for Carrying Out the Invention]FIG. 1 shows a cross-sectional structure of a pneumatic tire 1 according to an exemplary embodiment. Fig. 1 shows only one half of the structure in an axial direction of the tire, and the pneumatic tire 1 proper is approximately right-left symmetrical with respect to a center line C. The axial direction of the tire is represented by an arrow A in Fig. 1, and a radial direction of the tire is represented by an arrow B in Figs. 1 and 2.The pneumatic tire 1 is provided with bead portions 9 on both sides in the tire axial direction. Each bead part 9 includes a bead core formed of circularly wound steel wire and a rubber bead filler provided on an outer side in the radial direction of the bead core.One or two carcass plies 2 are suspended over the bead portions 9 on both sides in the tire axial direction. The carcass ply 2 is a sheet-shaped member in which many ply cords oriented orthogonally to the circumferential direction of the tire are coated with rubber. The carcass plies 2 form a frame shape of the pneumatic tire 1 between the bead parts 9 on both sides in the tire axial direction and wrap the bead parts 9 by being turned up from the inside to the outside in the tire axial direction and wound around the bead parts 9. Moreover, a rubber chafer 3 is provided at a location on an outer side in the tire axial direction of a turned-up portion 2a in the carcass plies 2.One or a plurality of belts 4 are provided on an outer side in the radial direction of the tire of the carcass plies 2, and a belt reinforcing layer 5 is provided on an outer side in the radial direction of the tire of the belts 4. The belt 4 is a member formed of many steel cords coated with rubber. The belt reinforcing layer 5 is a member formed of many organic fiber cords coated with rubber. A tread rubber 6 is provided on an outer side in the radial direction of the belt reinforcing layer 5. On the tread rubber 6, many grooves forming a tread pattern are formed.The sidewall rubbers 7 are provided on both sides of the carcass plies 2 in the tire axial direction. The tread rubber 6 and the sidewall rubber 7 overlap on a support, but each of the tread rubbers 6 and the sidewall rubbers 7 may overlap on a tire surface side. A portion of the sidewall rubber 7 on an inner side in the tire radial direction extends near the bead part 9 and covers a part of the rubber chafer 3.A rim line 8 which is a small protrusion having a height of about 1 mm is formed at a boundary between the sidewall rubber 7 and the rubber chafer 3 on the tire surface. The rim line 8 extends circumferentially in the circumferential direction of the tire. Preferably, at the same location as the rim line 8, instead of the rim line 8, a rim guard is provided which has an approximately triangular shape in cross section. A range from the rim line 8 or the rim protector to a tread end in the tire radial direction is determined as a sidewall surface 10. Here, the tread end denotes an end in the tire axial direction of a ground contacting surface in the tread rubber 6 when the pneumatic tire 1 contacts a road surface.A sheet-shaped inner liner formed of rubber having low air permeability is bonded to the inside of the carcass ply 2. In addition to these members, members such as a belt base and a chafer are provided depending on the functional requirements of the tire.As shown in FIGS. 1 and 2, a decorative portion 11 is provided on at least one of the sidewall surfaces 10 on both sides in the tire axial direction. The decorative portion 11 is in the form of a ring centered on the rotation axis of the tire. The decorative portion 11 is a fixed width portion surrounded by an inner diameter-side line 12 having a small diameter circular shape and an outer diameter-side line 13 having a large diameter circular shape. The inner diameter side line 12 and the outer diameter side line 13 may be lines formed by recesses / protrusions or steps on the tire surface, or may be virtual lines that do not actually exist.A location of the decorative portion 11 in the tire radial direction may be a location on an outer side in the tire radial direction as the maximum width position of the pneumatic tire 1, and may be a location including the maximum width position of the pneumatic tire 1. Here, the maximum width position of the pneumatic tire 1 is a position at which the length in the tire axial direction is the largest from the surface of the one sidewall surface 10 in the axial direction to the surface of the other sidewall surface 10 in the tire axial direction.In FIG. 1, the decorative portion 11 is provided to include a location where an interface between the tread rubber 6 and the sidewall rubber 7 appears on the tire surface. The decorative portion 11 may be provided to include a location where a step appears on the surface of the side wall surface 10 as described above. The location at which the step appears on the surface of the sidewall surface 10 typically includes locations at the ends of the elements forming the tire. Such typical locations are, for example, the location of a wound end 2 bof the carcass plies 2 (an end of the wound part 2 aof the carcass plies 2) in the tire axial direction and the like, in addition to the location where the boundary surface between the tread rubber 6 and the sidewall rubber 7 appears on the tire surface as described above.As shown in FIG. 2, labels 15 are provided at two opposing positions in the annular decorative portion 11. The label 15 is formed by arranging a plurality of letters 16 in the circumferential direction of the tire. The plurality of letters 16 may indicate the name of a manufacturer, a product, a trademark, or the like. These letters 16 are also formed by being surrounded with recessed or protruded lines.Figs. 3 to 7 show embodiments useful for understanding the invention.A pattern 14 is provided at a position between the two labels 15. The pattern 14 is formed from certain figures. As shown in FIG. 4, the pattern 14 is provided on a first reference surface 21 which is recessed from the second reference surface 22 when a tire surface around the pattern 14 is a second reference surface 22. A contour 17 of the pattern 14 is formed by a step between the first reference surface 21 and the second reference surface 22.A plurality of protrusions 30 protruding from the first reference surface 21 are provided within the contour 17 forming the pattern 14. As shown in FIG. 3 to FIG. 5, each of the protrusions 30 is formed by a protruding surface 31 provided at a position higher than the first reference surface 21 (a position away from the first reference surface 21 in a direction perpendicular to the first reference surface 21), two side surfaces 33 that slope from both ends in a first direction of the protruding surface 31 so as to be perpendicular to the first reference surface 21, and slopes 32 that extend from the protruding surface 31 to both sides in a second direction.Here, the first direction and the second direction are orthogonal to each other. The first direction is represented by an arrow C and the second direction by an arrow D in FIG. 3 and FIG. 5, respectively. In FIG. 5, the protrusions 30 are respectively represented by solid lines and the protruding surfaces 31 are represented by dashed lines.The protruding surface 31 is a flat surface having predetermined lengths in the first direction and the second direction. A length of the protruding surface 31 in the first direction C is preferably 0.25 times or more to twice or less the length of the protruding surface 31 in the second direction D. In this embodiment, the protruding surface 31 is a rectangular surface formed of two sides extending in the first direction C and two sides extending in the second direction D. The protruding surface 31 is not parallel to the first reference surface 21 according to the present invention. therefore, the heights from the first reference surface 21 are the same on all sides of the protruding surface 31. The protruding surface 31 is the highest portion protruding from the first reference surface 21 in the protrusion 30 located at a higher position than the second reference surface 22 as shown in FIG. 4.The slopes 32 extend from the ends of the protruding surface 31 in the second direction D to the first reference surface 21 while being inclined with respect to the first reference surface 21. The slopes 32 are flat surfaces. The two slopes 32 on both sides of the protruding surface 31 have the same inclination angle θ with respect to a direction perpendicular to the first reference surface 21 (see FIG. 4 ). Accordingly, the protrusion 30 has an isosceles trapezoidal shape when viewed from the first direction C. The inclination angle θ of the slope 32 with respect to the direction perpendicular to the first reference surface 21 is preferably 15 degrees or more to 75 degrees or less, and more preferably is 45 degrees or more to 75 degrees or less. The slope 32 has a rectangular shape when viewed from a perpendicular direction. A line of intersection between the slope 32 and the first reference surface 21 corresponds to a second direction end 34 of the protrusion 30.A length of the protruding surface 31 in the first direction C (i.e., the length of the protrusion 30 in the first direction C) is shorter than a length of the protrusion 30 in the second direction D. However, the length of the protrusion 30 in the second direction D is preferably 30 times or less the length of the protruding surface 31, and is preferably 20 times or less. The length of the protruding surface 31 in the first direction C is, for example, 0.8 mm or more to 1.2 mm or less. The height of the protrusion 30 (i.e., the length from the first reference surface 21 to the protruding surface 31 in the direction perpendicular to the first reference surface 21) is, for example, 0.1 mm or more to 1.5 mm or less.Many (for example, 50 or more) of the protrusions 30 described above are disposed within the contour 17 of the pattern 14. These protrusions 30 are arranged such that the first direction C corresponds to the radial direction of the tire and the second direction D corresponds to the circumferential direction of the tire.A plurality of protrusions 30 are arranged in the circumferential direction of the tire as the second direction D to form a protrusion line 23. In the projection line 23, gaps 24 are provided between adjacent projections 30. Accordingly, the protrusions 30 and the gaps 24 are alternately provided in the protrusion line 23. The second direction D is a direction in which the protrusions 30 do not contact each other by sandwiching the gaps 24 therebetween, which is a non-contact arrangement direction. In the gap 24, the first reference surface 21 is exposed to the tire surface.The lengths of all the gaps 24 in the second direction D are of equal length in all the protrusion lines 23. Therefore, the protrusions 30 are arranged at equal intervals in the second direction D. Accordingly, the protruding surfaces 31 of the protrusions 30 are also arranged at equal intervals in the second direction D. A length L 2 of the gap 24 in the second direction D (see FIG. 5 ) is preferably 3 / 4 or less of the length of the protrusion 30 in the second direction D.As shown in FIG. 3 and FIG. 5, in the pattern 14, a plurality of protrusion lines 23 are arranged in parallel to each other. As shown in FIG. 5, gaps 25 are provided between the adjacent protrusion lines 23. Accordingly, the protrusion lines 23 and the gaps 25 are alternately arranged in the first direction C. The first direction C is a direction in which the protrusions 30 do not contact each other by sandwiching the gaps 25 therebetween, which is a non-contact arrangement direction. In the gap 25, the first reference surface 21 is exposed to the tire surface. A length L 1 of the gap 25 in the second direction D (see FIG. 5 ) is preferably 3 / 4 or less of the length of the protrusion 30 in the first direction C.As for the relationship between adjacent protrusion lines 23, one protrusion line 23 is shifted with respect to the other protrusion line 23 in the second direction D. Therefore, the positions of the protrusions 30 and their protruding surfaces 31 are shifted in the second direction D between two adjacent protrusion lines 23. A pitch of the displacement is a half pitch (i.e., half a pitch) in the projection line 23, at which time a pitch in the projection line 23 corresponds to the sum of lengths of a projection 30 and a gap 24 adjacent to the projection 30 in the second direction D. The pitches of the displacement in the second direction D are equal between all the adjacent projection lines 23. Since the protrusion lines 23 are shifted in this manner, the protrusion surfaces 31 of the protrusions 30 and the gaps 24 in the second direction D are alternately arranged in the first direction C as shown in FIG. 5.These protrusions 30 may be formed by a mold used at the time of vulcanization of the pneumatic tire 1. On the mold surface of the mold used in vulcanization, irregularities corresponding to the shapes of the protrusions 30 are formed. Such irregularities may be generated by cutting or laser machining.As described above, the protrusion 30 provided in the decorative portion 11 includes the protruding surface 31 provided at a higher position than the first reference surface 21, and the slopes 32 inclinedly extending from the protruding surface 31 to the first reference surface 21 on both sides of the protruding surface 31 in the second direction in the pneumatic tire 1 according to the embodiment. Here, the length of the protruding surface 31 in the first direction C is shorter than the length of the protrusion 30 in the second direction D. Then, the plurality of protrusion lines 23 are formed in which the plurality of protrusions 30 are respectively arranged in the second direction D, and the positions of the protrusions 30 are shifted side by side in the second direction D in the protrusion lines 23. In addition, both the first direction C and the second direction D are the non-contact arrangement directions, and the gaps 24, 25 are provided between the protrusions 30 in the non-contact arrangement directions.According to the configuration, a plurality of surfaces having small areas (the protruding surfaces 31, the slopes 32, and the first reference surface 21) are provided, and the light is reflected on each of the surfaces. Since the light is reflected on a plurality of surfaces in this way, the pattern 14 in the decorative region 11 has both a glossy and a three-dimensional appearance. Accordingly, the pattern 14 becomes excellent in appearance and appearance in the decorative portion 11. When a person views the projection 30 from one of the two slopes 32 with the projecting surface 31 interposed therebetween, the one slope 32 looks glossy and the other slope 32 dark. Since there are many protrusions 30 in the pattern 14, fine patterns of light and dark are seen in the pattern 14, making the pattern 14 fine. The reflection of the light on the various surfaces described above produces new optical effects.When the pneumatic tire 1 is inflated, a thin depression may be formed on the sidewall surface 10 extending in the radial direction of the tire. However, this depression is made to be non-noticeable by a plurality of projections 30 on the pattern 14 in the decorative region 11.Since such a depression is more conspicuous on the outer side in the tire radial direction than at the maximum width position of the pneumatic tire 1, the effect of making the depression conspicuous is enhanced when the decorative portion 11 is disposed on the outer side in the tire radial direction than at the maximum width position. When the decorative portion 11 is disposed at an end of the member constituting the tire, the effect that the step appearing on the surface of the sidewall surface 10 is not noticeable can be achieved by the end.Moreover, new optical effects can also be produced by the presence of the gaps 24, 25 between the projections 30. For example, when the light reflected at the gap 24 between the protrusions 30 in the second direction D enters the human eyes, the light reflected at a deep part in the slope 32 of the protrusion 30 (a part near the first reference surface 21) does not easily enter the human eyes. Thus, when the gap 24 between the protrusions 30 appears light in the second direction D, the deep part in the slope 32 appears dark. As described above, by the presence of the gap 24 between the protrusions 30 in the second direction D, a difference is generated between the part that appears bright and the part that appears dark, which can produce new optical effects. Depending on the viewing angle, the gap 25 between the projections 30 in the first direction C likewise looks lighter or darker than an edge region, which can produce new optical effects.Since the gaps 24, 25 are formed between the protrusions 30, a crack is not easily generated at an end of the protrusion 30 as in the case where the protrusions 30 contact each other.The lengths of the plurality of gaps 24 in the second direction D are equal, and the lengths of the plurality of gaps 25 in the first direction C are also equal. That is, the protrusions 30 are arranged at equal intervals in the second direction D, and the protrusion lines 23 are arranged at equal intervals in the first direction C. Accordingly, gradation of constant repetition of light and dark is generated in the pattern 14.The inclination angles θ of the two slopes 32 are equal with respect to a protruding surface 31 in the direction perpendicular to the first reference surface 21; therefore, the gradation of light and shade can be similarly seen when a person views the pattern 14 from an arbitrary side of the two slopes 32 of the protrusion 30.Since the second direction D of the protrusion 30 is the circumferential direction of the tire, unique optical effects can be generated when the pneumatic tire 1 rotates.The first reference surface 21 is recessed to be lower than the second reference surface 22 therearound, and the protrusions 30 are provided on the first reference surface 21. However, the protruding surfaces 31 of the protrusions 30 are higher than the second reference surface 22, and according to the configuration, much light is applied to the portions of the protrusions 30 in the vicinity of the protruding surfaces 31 to generate high reflection, and the light is not sufficiently applied to the portions of the protrusions 30 in the vicinity of the first reference surface 21 to generate low reflection. Therefore, the portions of the protrusions 30 near the protruding surfaces 31 look bright and the portions of the protrusions 30 near the first reference surface 21 look dark, producing optical effects in which the contrast of bright and dark is emphasized.In addition, since the protruding surfaces 31 of the protrusions 30 are parallel to the first reference surface 21, the light reflected by the protruding surfaces 31 and the light reflected by the first reference surface 21 move in the same direction. Therefore, when the projected surfaces 31 look light, the first reference surface 21 also looks light and nice.When the inclination angle θ of the slope 32 of the protrusion 30 with respect to the direction perpendicular to the first reference surface 21 is 15 degrees or more, the irregularities for forming the protrusions 30 in the mold used at the time of vulcanization are not too deep. Accordingly, the air flow in the irregularities in the mold at the time of vulcanization is good, therefore occurrence of air entrapment is reduced and defects are hardly caused in the pneumatic tire 1. When the inclination angle θ of the slope 32 is 45 degrees or more, the above-mentioned effects become more clearly visible. When the inclination angle θ of the slope 32 is 75 degrees or less, the height of the protrusions 30 is secured to some extent; therefore, the effects obtained by the presence of the protrusions 30 become more remarkable.The above embodiment is merely an example, and the scope of the invention is not limited to the above embodiment. Various modifications may be made to the above embodiment within a scope not departing from the gist of the invention. A plurality of modification examples will be explained below. Each of the various modification examples can be applied to the above embodiment, and two or more examples of the various modification examples can be combined and applied in a range where no contradiction occurs.<Change Example 1>One direction of the first direction C and the second direction D may be the non-contact arrangement direction (the direction in which the protrusions 30 are arranged without contacting each other), and the protrusions 30 may be arranged while contacting each other in the other direction. For example, it is preferable that the plurality of protrusions 30 are arranged at equal intervals in the second direction D to form the protrusion line, and that adjacent protrusion lines contact each other in the first direction C. It is also preferable that the plurality of protrusions 30 are arranged in the second direction D while contacting each other to form the protrusion line, and that the protrusion lines are arranged at equal intervals in the first direction C.<Change Example 2>There may be long gaps and short gaps as the gaps between the protrusions 30, and the long gaps and the short gaps may be alternately arranged in the non-contact arrangement direction.FIG. 6 is, for example, a view showing a case where the second direction D is the non-contact arrangement direction. In FIG. 6, the plurality of protrusions 30 are arranged with gaps in the second direction D to form a protrusion line 123. It is assumed that there is no gap between the protrusion lines 123 in the first direction C and that the protrusion lines 123 contact each other, although not illustrated. (However, the protrusion line 123 is disposed to be displaced in the second direction D with respect to the adjacent protrusion line 123).There are a long gap 124 aand a short gap 124 bas the gaps in the second direction D. Then, the long gaps 124 aand the short gaps 124 bare alternately arranged in the second direction D. The gradation of light and dark in the pattern 14 is cyclic by the above arrangement of the gaps 124a, 124b.There is a case where the protrusions contact each other in the second direction D and only the first direction C is the non-contact arrangement direction. In this case, it is possible that the long gaps and the short gaps are provided as the gaps between adjacent protrusion lines 123 in the first direction C, and that the long gaps and the short gaps are alternately arranged in the first direction C.When both the first direction C and the second direction D are the non-contact arrangement direction, the long gaps and the short gaps may be alternately arranged in both the first direction C and the second direction D, or the long gaps and the short gaps are alternately arranged only in one of the first direction C and the second direction D, and the arrangement of the gaps according to the above embodiment or another modification example may be adopted as an arrangement of the gaps in the other direction.< Example 3>There may be three or more kinds of gaps having different lengths than the gaps between the protrusions 30, and the length of the gaps may be gradually changed in the direction of non-contact arrangement.For example, FIG. 7 is a view showing the case where the second direction D is the non-contact arrangement direction. In FIG. 7, the plurality of protrusions 30 are arranged with gaps in the second direction D to form a protrusion line 223. It is assumed that there is no gap between the protrusion lines 223 in the first direction C and that the protrusion lines 223 contact each other, although not illustrated. (However, the protrusion line 223 is disposed to be displaced in the second direction D with respect to the adjacent protrusion line 223.).There are a long gap 224 a, a short gap 224 bof medium length, and a short gap 124 cas the gaps in the second direction D. Then, the long gap 224 a, the gap 224 bof medium length, and the short gap 224 care arranged in this order in the second direction D. The arrangement of the three gaps 224 a, 224 b, and 224 cis repeated in the second direction D. The light-dark gradation in the pattern 14 becomes a long cyclic property due to the arrangement of the gaps 224a, 224b, and 224c.In other words, there are the short gap, the middle gap, and the long gap as the gaps between adjacent protrusions 30. when here a length of the short gap in the second direction D is LA, a length of the middle gap in the second direction D is LB, and a length of the long gap in the second direction D is LC, the relationship LA<LB<LC holds. Then, the short gap, the short gap, and the long gap are arranged in this order toward a direction in the second direction D. The arrangement in the order of the short gap, the middle gap, and the long gap is repeated in the second direction D.There may be more than three types of gaps between adjacent protrusions 30. For example, it is preferable that there are a plurality of lengths such as LB 1, LB 2... as lengths of the central gap in the second direction D, and that the relationship LA<LB 1<LB 2<... <LC holds.There is a case where the protrusions contact each other in the second direction D and only the first direction C is the non-contact arrangement direction. In this case, the long gap, the middle gap, and the short gap may be provided as the gaps between adjacent protrusion lines 223 in the first direction C, and the length of the gaps may be gradually changed in the first direction C.When both the first direction C and the second direction D are the non-contact arrangement direction, the length of the gaps in both the first direction C and the second direction D may be gradually changed, or the length of the gaps in only one of the first direction C and the second direction D may be gradually changed, and the arrangement of the gaps according to the above embodiment or another modification example may be adopted as the arrangement of the gaps in the other direction.< Example 4>The directions in arrangement of the protrusions 30 are not limited to the directions of the embodiment. For example, the first direction C may be the circumferential direction of the tire and the second direction D may be the radial direction of the tire. When the protrusions 30 are arranged such that the first direction C is the circumferential direction of the tire, the appearance of the pattern 14 changes as compared with the above embodiment.Moreover, within the pattern 14, a region where the protrusions 30 where the first direction C is the radial direction of the tire are combined and a region where the protrusions 30 where the first direction C is the circumferential direction of the tire are combined may be formed. In addition, the protrusions 30 in which the first direction C is the radial direction of the tire and the protrusions 30 in which the first direction C is the circumferential direction of the tire are mixed in the pattern 14.< Example 5>As shown in FIG. 8, a protruding surface 331 of a protrusion 330 is inclined with respect to the first reference surface 21 according to the present invention. In a preferred example, the first direction C is the radial direction of the tire and the second direction D is the circumferential direction of the tire, and the protruding surface 331 is inclined such that one side in the radial direction of the tire becomes low and the other side becomes high.In the above-mentioned preferred inclination, the slopes 332 have their slopes symmetrical with respect to the direction perpendicular to the first reference surface 21 on both sides of the protruding surface 331 in the second direction D (the circumferential direction of the tire). Moreover, the inclination angles of the slopes 332 with respect to the direction perpendicular to the first reference surface 21 (for explanation of the modification example, the inclination angle with respect to the direction perpendicular to the first reference surface 21 is referred to only as "inclination angle") are different on both sides of the protrusion 330 in the first direction C. Specifically, the inclination angle of the slope 332 at an end 331 aat which the height from the first reference surface 21 is higher is larger than the inclination angle of the slope 332 at an end 331 bthat is lower. As specific numerical values, the inclination angle at the higher end 331 ais preferably 20 degrees or more to 80 degrees or less, and the inclination angle at the lower end 331 bis preferably 15 degrees or more to 75 degrees or less.Conversely, the inclination angle of the slope 332 at the upper end 331 amay be smaller than the inclination angle of the slope 332 at the lower end 331 b. It is also preferable that the inclination angle of the slope 332 at the upper end 331 aand the inclination angle of the slope 332 at the lower end 331 bare equal.When the protruding surface 331 of the protrusion 330 is inclined with respect to the first reference surface 21 as described in this modification example, the appearance of the pattern 14 becomes fine, which is different from the case where the protruding surface 331 is parallel to the first reference surface 21 as in the above embodiment.< Example 6>As shown in FIG. 9, the protruding surfaces 31 that are the highest portions of the protrusions 30 may be lower than the second reference surface 22 when the first reference surface 21 is recessed from the second reference surface 22 therearound. The protrusions 30 are protected by the second reference surface 22 in this modification example, which can prevent damage to the protrusions 30.< Example 7>As shown in FIG. 10, it is preferable that the first reference surface 21 protrudes from and around the second reference surface 22, and that the protrusions 30 are provided on the first reference surface 21. In this modification example, much light is applied to the slopes 32 of the protrusions 30, therefore the protrusions 30 appear more luminous.<Change Example 8>The pattern provided in the decorative region 11 is not limited to the pattern shown in FIG. 2. Preferably, instead of the pattern 14, a mark (for example, in the form of a letter, a symbol or a figure) or the like may be provided, and the plurality of protrusions 30 may be provided within a contour of the mark or the like.Preferably, no protrusion 30 is provided within the contour 17 of the pattern 14 (or the contour of the mark), and the plurality of protrusions 30 are provided outside the contour. In this case, the pattern 14 (or the mark or the like) is provided as a region in which no protrusion 30 is provided within the region in which the plurality of protrusions 30 are provided.< Example 9>The distance of displacement in the second direction D in adjacent projection lines 23 is not limited to half pitch of the projection line 23, but may be 2 / 3 pitch or the like.<Change Example 10>It is not always necessary that the inclination angles θ of the two slopes 32 of a protrusion 30 are equal with respect to the direction perpendicular to the first reference surface 21.[List of Reference Numerals]C center line 1 pneumatic tire 2 carcass ply 2 aturned part 2 bcoiled end 3 rubber chafer 4 belt 5 belt reinforcing layer 6 tread rubber 7 sidewall rubber 8 rim rim 9 bead part 10 sidewall surface 11 decorative portion 12 inner diameter side line 13 outer diameter side line 14 pattern 15 label 16 letter 17 outline 21 first reference surface 22 second reference surface 23 protrusion line 24 gap (second direction) 25 gap (first direction) 30 protrusion 31 protruding surface 32 slope 33 lateral surface 34 second direction end 123 protrusion line 124 alength gap 124 blength gap 223 protrusion line 224 alength gap 224 blength gap 224 clength gap 330 protrusion 331 protruding surface 331 aend 331 bend 332 slope

Claims

A pneumatic tire, comprising: a decorative portion (11) on a sidewall surface (10); and a first reference surface (21) and a plurality of protrusions (30, 330) protruding from the first reference surface (21) on the decorative portion (11), each of the protrusions (30, 330) having a protruding surface (31, 331) provided at a position higher than the first reference surface (21) and having predetermined lengths in a first direction and a second direction, and slopes (32, 332), the slopes (32, 332) extending from the protruding surface (31, 331) to the first reference surface (21) on both sides in the second direction, the protruding surface (31, 331) being interposed therebetween while the slopes (32, 332) are inclined with respect to the first reference surface (21), wherein a length of the protruding surface (31, 331) in the first direction is shorter than a length of the protrusion (30, 330) in the second direction, wherein a plurality of protrusion lines (23, 123, 223) in which the plurality of protrusions (30, 330) are respectively arranged in the second direction are formed, and positions of the protrusions (30, 330) in the second direction are arranged displaced in the protrusion lines (23, 123, 223) adjacent to each other, wherein at least one of the first direction and the second direction is a non-contact arrangement direction in which gaps (24, 25, 124a, 124b, 224a, 224b, 224c) are provided between the protrusions (30, 330), and wherein the protruding surface (31, 331) is inclined with respect to the first reference surface (21).The pneumatic tire according to claim 1, wherein the plurality of protrusions (30, 330) are arranged at equal intervals in the non-contact arrangement direction.The pneumatic tire according to claim 1, wherein a long gap (124a) and a short gap (124b) are present as gaps, and the long gaps (124a) and the short gaps (124b) are alternately arranged in the non-contact arrangement direction.The pneumatic tire according to claim 1, wherein three or more kinds of gaps (224a, 224b, 224c) are present with different lengths than the gaps, and the lengths of the gaps (224a, 224b, 224c) are gradually changed in the non-contact arrangement direction.The pneumatic tire according to any one of claims 1 to 4, wherein each of the first direction and the second direction is the non-contact arrangement direction in which gaps (24, 25, 124a, 124b, 224a, 224b, 224c) are provided between the protrusions (30, 330) adjacent to each other.The pneumatic tire according to any one of claims 1 to 5, wherein the inclination angles of the two slopes (32, 332) with respect to a protruding surface (31, 331) are equal in a direction perpendicular to the first reference surface (21).The pneumatic tire according to any one of claims 1 to 6, wherein the second direction is a circumferential direction of the tire.The pneumatic tire according to any one of claims 1 to 6, wherein the second direction is a radial direction of the tire.The pneumatic tire according to any one of claims 1 to 8, wherein the first reference surface (21) is recessed to be deeper than the second reference surface (22) therearound, and the protruding surface (31, 331) is disposed at a higher position than the second reference surface (22).

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