Tire and tire forming mold

Abstract

Provided is a tire in which the black density is further improved compared to conventional tires, thereby achieving a higher contrast ratio. A tire (1) is provided with a pattern region (7) in a portion of the outer surface (3a) of a sidewall (3), the pattern region (7) being provided in a state of being visible as a different portion from the periphery of the portion, a plurality of protrusion assemblies (20) protruding from the surface (7a) of the pattern region (7) being disposed in the pattern region (7), each protrusion assembly (20) comprising: a main cone (30) as a first protrusion; the pattern area (7) is provided with a first slope foot part (37) which is continuous with the surface (7a) of the pattern area (7); and a plurality of sub-cones (40), which are second protrusions, disposed around the main cone (30), and disposed so that a part of the sub-cones (40) overlaps the first ramp foot section (37).

Description

Technical Field

[0001] The present invention relates to a tire having a pattern area for displaying, for example, a logo, a tread pattern, etc. on a part of the outer surface of the sidewall, and a tire molding die for molding the tire. Background Art

[0002] Conventionally, a tire having a pattern area formed by a plurality of minute protrusions provided on a part of the sidewall of the tire has been known (for example, Patent Document 1, etc.). In such a pattern area, the incident light is repeatedly reflected between the protrusions to generate a light absorption effect, whereby it is visually recognized as darker than the outer surface of the surrounding sidewall, and the contrast is improved. By providing such a pattern area, the tire can achieve, for example, an improvement in design effect and appearance.

[0003] Prior Art Documents

[0004] Patent Documents

[0005] Patent Document 1: Japanese Unexamined Patent Application Publication No. 2017-1440 Summary of the Invention

[0006] Problems to be Solved by the Invention

[0007] The high contrast achieved by a plurality of protrusions is less likely to undergo secular change compared to the method achieved by painting or the like, and has the advantage of maintaining its effect for a long time. Therefore, compared with the prior art, the black density is further increased to promote high contrast, and the formation of a pattern area based on protrusions is sought to further improve the design effect and appearance.

[0008] An object of the present invention is to provide a tire that achieves a higher contrast with a further increased black density compared to the prior art, and a tire molding die capable of manufacturing such a tire.

[0009] Means for Solving the Problems

[0010] The tire of the present invention has a pattern area on a part of the outer surface of the sidewall, the pattern area being provided in a state where it can be visually recognized as a part different from the surrounding of the part. Among them, a plurality of convex portion aggregates protruding from the surface of the pattern area are arranged in the pattern area. The convex portion aggregate includes: a main cone as a first convex portion, which has a first slope portion continuous with the surface of the pattern area; and a plurality of second convex portions, which are arranged around the main cone and are arranged in such a manner that at least a part thereof overlaps with the first slope portion of the main cone.

[0011] The tire molding die of the present invention is for molding the tire of the present invention. Among them, the tire molding die has a convex portion aggregate forming portion including a plurality of concave portions corresponding to the plurality of convex portion aggregates.

[0012] Advantages of the Invention

[0013] According to the present invention, it is possible to provide a tire with a further increased black density compared to the prior art, achieving a high contrast, and a tire molding die capable of manufacturing such a tire. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a side view of the tire of the embodiment.

[0015] Figure 2 It is a cross-sectional view showing an example of a molding die for vulcanizing and molding the tire of the embodiment.

[0016] Figure 3 It is a perspective view showing a state in which a plurality of convex portion aggregates provided in the pattern area of the tire of the embodiment are arranged in a first arrangement pattern.

[0017] Figure 4 It is Figure 3 a view taken in the direction of IV of

[0018] Figure 5 It is a side view showing the main cone and the sub-cone constituting the above-mentioned convex portion aggregate separately as monomers.

[0019] Figure 6 It is an enlarged top view of a pair of the above-mentioned convex portion aggregates.

[0020] Figure 7 It is a cross-sectional view showing a convex portion aggregate forming portion of a tire molding die for forming a plurality of the above-mentioned convex portion aggregates.

[0021] Figure 8 It is a perspective view schematically showing a convex portion aggregate in which an annular convex portion is formed around the main cone in the above-mentioned convex portion aggregate.

[0022] Figure 9 It is Figure 8 a view taken in the direction of IX of

[0023] Figure 10 It is a perspective view showing an example of a convex portion aggregate in which an annular convex portion formed by a plurality of sub-cones is formed around the main cone in the above-mentioned convex portion aggregate.

[0024] Figure 11 It is Figure 10 a view taken in the direction of XI of

[0025] Figure 12 It is a perspective view showing a state in which a plurality of convex portion aggregates provided in the pattern area of the tire of the embodiment are arranged in a second arrangement pattern.

[0026] Figure 13 It isFigure 12 View XIII

[0027] Figure 14 is an enlarged top plan view of a plurality of convex portion aggregates arranged in the above-described second arrangement pattern.

[0028] Explanation of reference numerals:

[0029] 1... tire, 3... sidewall, 3a... outer surface of sidewall, 7... pattern area, 7a... surface of pattern area, 10... tire forming die, 20... convex portion aggregate, 30... main cone (first convex portion), 37... first slope foot portion, 40... sub-cone (second convex portion), 47... second slope foot portion, 51... first overlapping portion, 52... second overlapping portion, 60... annular convex portion (second convex portion), 61... top of annular convex portion, 100... convex portion aggregate forming portion, 130... main concave portion (concave portion), 140... sub-concave portion (concave portion), h1... height of main cone, h2... height of sub-cone. Detailed Description of the Invention

[0030] Hereinafter, the embodiments will be described with reference to the drawings. Figure 1 is a side view of the tire 1 of the embodiment. The tire 1 is a so-called pneumatic tire in which a predetermined air pressure is filled in its inner cavity. The tire 1 of the embodiment is a pneumatic tire for passenger cars including light vehicles, SUVs, etc. It should be noted that the structure of the tire 1 of the embodiment can also be applied to pneumatic tires for other vehicle types such as light trucks, trucks, and buses.

[0031] First, with reference to Figure 1 a summary of the main side-related structure of the tire 1 will be described. Figure 1 is a side view of the tire 1 as viewed from the direction of the tire rotation axis X. It should be noted that the tire axial direction, the tire circumferential direction, and the tire radial direction in the following description are as follows. The tire axial direction is the extending direction of the tire rotation axis X, and in Figure 1 it is the front-back direction of the paper surface. It should be noted that when viewed from the tire radial direction, the tire axial direction is the left-right direction, and thus the tire axial direction is sometimes referred to as the left-right direction. The tire circumferential direction is an arc line centered on the tire rotation axis X and is the direction along the rotation direction of the tire 1, and is indicated by an arrow G in Figure 1 . The tire radial direction is the direction perpendicular to the tire rotation axis X and is arbitrarily indicated by an arrow Y in Figure 1 .

[0032] As Figure 1 shown, the tire 1 includes a bead 2, a sidewall 3 extending from the bead 2 in the tire radial direction toward the tire radial outside away from the tire rotation axis X, and a tread 4. The bead 2 and the sidewall 3 are respectively in Figure 1One side 1s of the tire 1 shown and the other side not shown in the figure, which is separated axially of the tire, each have one, that is, a pair of left and right. The tread 4 is disposed between the radially outer sides of the left and right sidewalls 3. The outer peripheral surface of the tread 4 includes a tread surface that contacts the road surface. Figure 1 The tire 1 is configured with various rubbers that respectively form the bead 2, the sidewall 3, and the tread 4 as the main body. A carcass ply that forms the framework of the tire 1 is disposed on the inner cavity side of the rubber that forms the entire tire 1. Further, an airtight layer that maintains the air pressure is disposed on the inner cavity side of the carcass ply. In addition, an annular reinforcing belt layer (the carcass ply, the airtight layer, and the reinforcing belt layer are omitted from the illustration) is embedded inside the rubber that forms the tread 4. It should be noted that, in addition to these components, various components are provided as needed in terms of the functions of the tire 1.

[0033] As shown in

[0034] As shown, the sidewall 3 has an annular decorative area 5 on its outer surface 3a that extends over the entire circumference of the tire. The decorative area 5 is a region with a constant width that is sandwiched between an inner arc line 5a on the radially inner side of the tire that is closer to the tire rotation axis X in the tire radial direction and an outer arc line 5b that is on the radially outer side of the inner arc line 5a. The inner arc line 5a and the outer arc line 5b can be lines formed by concave, convex, or stepped portions on the outer surface 3a of the sidewall 3, or can be imaginary lines that do not actually exist. Figure 1 The radial position of the decorative area 5 on the outer surface 3a of the sidewall 3 can be located on the radially outer side of the position of the maximum tire width, or can be located at a position that includes the position of the maximum tire width. It should be noted that the position of the maximum tire width refers to the position where the axial length between the outer surfaces 3a of the left and right sidewalls 3 is the longest.

[0035] The tire 1 has a pattern area 7 on a part of the outer surface 3a of the sidewall 3, and the pattern area 7 is set to be visually recognizable as a part different from the surrounding area of this part. The pattern area 7 is provided on the sidewall rubber, which is a black rubber member that forms the outer surface 3a of the sidewall 3.

[0036] As shown in

[0037] As shown, mark portions 6A are provided at two positions on the annular decorative area 5 that are opposed to each other across the tire rotation axis X. The mark portions 6A are formed by arranging a plurality of characters along the tire circumference. Through these plurality of characters, at least one of marks such as the manufacturer name, product name, brand, etc. is displayed. Each character can be formed by being bordered by concave or convex lines, or the entire character can be formed by concave or convex. For example, each character of the mark portion 6A is provided as the pattern area 7 of the embodiment. Figure 1

[0038] Figure 1 As shown Figure 1As shown, in the annular decorative area 5, pattern portions 6B are provided at two positions circumferentially sandwiched by two badge portions 6A. In the pattern portion 6B, a pattern is provided in which a parallelogram is curved following the annular decorative area 5. For example, each pattern of the pattern portion 6B is also set as the pattern area 7 of the embodiment.

[0039] It should be noted that the shape of the pattern area 7 is not limited to this, and various shapes can be cited, such as any shape, or the shape of a badge depicting the above-mentioned manufacturer name, product name, brand, etc., or the shape of other numbers, characters, etc.

[0040] Each of the above-mentioned pattern areas 7 in the embodiment has a surface 7a along the contour of the sidewall 3. A plurality of convex portion aggregates 20 described later are formed on the surface 7a. The pattern area 7 is an area set to be visually recognizable as a portion different from the periphery of the pattern area 7 by forming a plurality of convex portion aggregates 20.

[0041] Figure 2 An example of a tire forming die for vulcanizing and forming the tire 1 of the embodiment is shown. Figure 2 This is a meridian sectional view along the axial direction of the formed tire 1 of such a tire forming die 10.

[0042] Figure 2 The shown tire forming die 10 includes a plurality of sector dies 11 arranged in a circular shape along the outer peripheral side of the tire 1, a pair of side plates 12 disposed on both axial sides of the annular body formed by the combination of the plurality of sector dies 11, and a pair of bead rings (not shown). At the time of vulcanization molding, as shown by the dashed line in Figure 2 , an unvulcanized tire 1a to be the tire 1 is disposed inside the tire forming die 10. The combination of the sector die 11, the side plate 12, and the bead ring is a forming die for forming the tire 1, and the outer surface of the entire tire 1 is formed by the inner surfaces of this forming die, that is, the inner surface 11a of the sector die 11, the inner surface 12a of the side plate 12, and the inner surface of the bead ring. Further, at the time of vulcanization molding, an airbag (not shown) that presses the unvulcanized tire 1a against the inner surface of the tire forming die 10 is disposed inside the unvulcanized tire 1a. The tread 4 is mainly formed by the plurality of sector dies 11, and the sidewall 3 is mainly formed by the pair of side plates 12. The bead 2 is formed by the pair of above-mentioned bead rings, and the entire inner surface of the tire 1 is formed by the above-mentioned airbag.

[0043] The unvulcanized tire 1a is vulcanized using the tire forming die 10 to form the rubber shape of the entire tire 1, and a plurality of convex portion aggregates 20 described below are formed in the above-mentioned pattern area 7.

[0044] Figure 3 and Figure 4FIG. 0 is a view showing a plurality of convex portion aggregates 20 arranged in a pattern area 7. Figure 3 It is a perspective view. Figure 4 FIG. 1 is a plan view and is Figure 3 a view taken in the direction IV. Figure 3 and Figure 4 The plurality of convex portion aggregates 20 shown in FIGS. 2 and 3 are arranged in the pattern area 7 by a first arrangement pattern 21. The plurality of convex portion aggregates 20 are arranged on the surface 7a of the pattern area 7 in a state of filling the entire area of the pattern area 7. It should be noted that hereinafter, the surface 7a of the pattern area 7 may sometimes be referred to as the pattern area surface 7a.

[0045] The convex portion aggregate 20 of the embodiment includes a main cone 30 as a first convex portion and a plurality of sub-cones 40 as second convex portions. There is one main cone 30, and a plurality of sub-cones 40 are arranged around the one main cone 30 disposed at the center of the convex portion aggregate 20 so as to surround the main cone 30.

[0046] Figure 5 In order to clearly show the shapes of the main cone 30 and the sub-cones 40, they are shown separately as single entities. Figure 5 The left side of FIG. 4 is a side view of the main cone 30, Figure 5 and the right side of FIG. 4 is a side view of the sub-cone 40.

[0047] As Figure 5 shown, the main cone 30 is a conical protrusion protruding from the pattern area surface 7a. The main cone 30 has a conical side surface 31 and a top portion 32 formed by being flatly cut. The main cone 30 is arranged on the surface 7a with its top portion 32 being the farthest from the pattern area surface 7a. The main cone 30 has a hypothetical bottom surface 33 that is integral with the pattern area surface 7a and is coplanar with the surface 7a. The bottom surface 33 is a perfect circular shape. The main cone 30 has a central axis 30c that connects the center of the bottom surface 33 and a hypothetical vertex on the top portion 32. The central axis 30c extends perpendicularly to the pattern area surface 7a. Therefore, the main cone 30 is a straight cone protruding perpendicularly from the pattern area surface 7a.

[0048] The main cone 30 of the embodiment includes a conical base portion 35 that is continuous with the surface 7a of the pattern area 7 and a conical front portion 36 that extends in a direction away from the pattern area surface 7a. The front portion 36 is concentric with the base portion 35. The side surface 31 of the main cone 30 includes a base side surface 35a that is the side surface of the base portion 35 and a front side surface 36a that is the side surface of the front portion 36.

[0049] As Figure 5As shown, the inclination angle θ1 of the base side surface 35a of the main cone 30 is larger than the inclination angle θ2 of the front side surface 36a. The inclination angles in this case are the angles of the respective side surfaces 35a, 36a with respect to the line perpendicular to the surface 7a of the pattern area when viewed from the side. The base 35 includes a first slope foot portion 37 continuous with the surface 7a of the pattern area. The cross-sectional shape of the main cone 30 parallel to the surface 7a of the pattern area is a perfect circle shape from the bottom surface to the top. The area of the cross-sectional shape of the main cone 30 parallel to the surface 7a of the pattern area gradually decreases as it goes from the bottom surface 33 towards the top 32, but the degree of its decrease changes at the boundary between the base 35 and the front portion 36. That is, regarding the degree of decrease of the area of this cross-sectional shape, the base 35 with the larger inclination angle is larger than the front portion 36.

[0050] It should be noted that the bottom surface 33 of the main cone 30 in the embodiment is a perfect circle shape, but it can also be an elliptical shape. In addition, the flat surface of the top 32 in the embodiment is a circular shape substantially parallel to the bottom surface 33, but it can also not be parallel to the bottom surface 33. Furthermore, the top 32 can be not flatly cut and be in a sharp form, or can be formed into a spherical shape.

[0051] As Figure 5 shown, the sub-cone 40 is a conical protrusion protruding from the surface 7a of the pattern area. The sub-cone 40 has the same shape as the main cone 30 and is a conical protrusion with a reduced scale. That is, the sub-cone 40, like the main cone 30, has a conical side surface 41, a top 42 formed by flat cutting, and a bottom surface 43 with a perfect circle shape. The sub-cone 40 is arranged on the surface 7a with its top 42 being the farthest from the surface 7a of the pattern area. The sub-cone 40 has a central axis 40c that connects the center of the bottom surface 43 to the imaginary vertex on the top 42. The sub-cone 40 is also a straight cone in which the central axis 40c extends perpendicular to the surface 7a of the pattern area, just like the main cone 30.

[0052] The sub-cone 40 in the embodiment includes a conical base 45 continuous with the surface 7a of the pattern area 7 and a conical front portion 46 extending from the base 45 in a direction away from the surface 7a of the pattern area. The front portion 46 is concentric with the base 45. The side surface 41 of the sub-cone 40 includes a base side surface 45a that is the side surface of the base 45 and a front side surface 46a that is the side surface of the front portion 46.

[0053] As Figure 5As shown, in the case of the side view of the sub-cone 40, with respect to the inclination angle with respect to the line perpendicular to the surface 7a of the pattern region, the inclination angle θ3 of the base side surface 45a is larger than the inclination angle θ4 of the front side surface 46a. The base 45 includes a second slope foot portion 47 continuous with the surface 7a of the pattern region. The cross-sectional shape of the sub-cone 40 parallel to the surface 7a of the pattern region is circular from the bottom surface to the top. The area of the cross-sectional shape of the sub-cone 40 parallel to the surface 7a of the pattern region gradually decreases as it goes from the bottom surface 43 towards the top 42, but the degree of decrease changes at the boundary between the base 45 and the front portion 46. That is, with respect to the degree of decrease of the area of this cross-sectional shape, the base 45 with the larger inclination angle is larger than the front portion 46.

[0054] It should be noted that the bottom surface 43 of the sub-cone 40 in the embodiment is circular, but it can also be elliptical. In addition, the flat surface of the top 42 in the embodiment is a circular shape substantially parallel to the bottom surface 43, but it can also not be parallel to the bottom surface 43. Also, the top 42 can be not flatly cut but in a sharp form, or can be formed in a spherical shape.

[0055] As Figure 5 shown, the height h2 of the sub-cone 40 is smaller than the height h1 of the main cone 30. The height h1 of the main cone 30 and the height h2 of the sub-cone 40 are both the lengths of the respective central axes 30c, 40c from the surface 7a of the pattern region to the respective tops 32, 42.

[0056] In one convex portion aggregate 20, a plurality of sub-cones 40 are arranged concentrically around one main cone 30 and surround the main cone 30. The number of sub-cones 40 arranged around the main cone 30 is preferably three or more, and can also be four or more, or a number above that.

[0057] Figure 6 is an enlarged top view showing a pair of convex portion aggregates 20 arranged in the first arrangement pattern 21. As Figure 6 shown, a plurality of sub-cones 40 surrounding the main cone 30 are arranged at equal intervals in the circumferential direction. The second slope foot portions 47 of these plurality of sub-cones 40 constituting the convex portion aggregate 20 partially overlap each other. That is, a pair of adjacent sub-cones 40 in the circumferential direction have a common second overlapping portion 52 where the second slope foot portions 47 overlap each other.

[0058] In addition, the second slope foot portions 47 of a plurality of sub-cones 40 surrounding the main cone 30 respectively overlap partially with the first slope foot portion 37 of the main cone 30. That is, the second slope foot portion 47 of the sub-cone 40 and the first slope foot portion 37 of the main cone 30 have a common third overlapping portion 53 where they overlap each other.

[0059] As Figure 3 and Figure 4As shown, in the first arrangement pattern 21, a plurality of convex portion aggregates 20 are arranged in a linear arrangement portion 21A in a straight line at equal intervals in the first direction F1, and are arranged in multiple columns in the second direction F2 orthogonal to the first direction F1. In a pair of linear arrangement portions 21A adjacent in the second direction F2, the convex portion aggregates 20 of the linear arrangement portion 21A on one side are arranged in an interleaved manner with the convex portion aggregates 20 of the linear arrangement portion 21A on the other side.

[0060] In the linear arrangement portion 21A where a plurality of convex portion aggregates 20 are arranged in the first direction, as Figure 6 shown, the sub-cones 40 are adjacent to each other, and a pair of adjacent sub-cones 40 have a second overlapping portion 52 where the second slope feet portions 47 overlap each other. On the other hand, as Figure 4 shown, a gap is provided between the linear arrangement portions 21A adjacent in the second direction F2, and the second slope feet portions 47 of the adjacent sub-cones 40 do not overlap. That is, the pattern region surface 7a has a non-overlapping portion 55 where the second slope feet portions 47 of the sub-cones 40 do not overlap between the linear arrangement portions 21A adjacent in the second direction F2.

[0061] Figure 3 and Figure 4 shown, the first arrangement pattern 21 having a plurality of convex portion aggregates 20 can be formed by the side plate 12 of the above-mentioned tire forming die 10. As Figure 7 shown, the side plate 12 may include a convex portion aggregate forming portion 100 in which these plurality of convex portion aggregates 20 are formed.

[0062] Figure 7 is a cross-sectional view showing a state in which a plurality of convex portion aggregate forming recesses 110 are formed on the inner surface 12a of the side plate 12. As Figure 7 shown, the plurality of convex portion aggregate forming recesses 110 are respectively depressions corresponding to the convex portion aggregates 20 formed in the pattern region 7 after vulcanization, and include one main recess 130 and a plurality of sub-recesses 140.

[0063] The main recess 130 is a conical depression corresponding to the shape and size of the main cone 30. The sub-recesses 140 are conical depressions corresponding to the shape and size of the sub-cones 40. The plurality of sub-recesses 140 are arranged around one main recess 130 so as to surround the main recess 130. The plurality of convex portion aggregate forming recesses 110 are arranged on the inner surface 12a of the side plate 12 in a pattern corresponding to the first arrangement pattern 21. The convex portion aggregate forming portion 100 includes these plurality of convex portion aggregate forming recesses 110. The main recess 130 and the sub-recesses 140 are an example of the plurality of recesses of the present disclosure included in the convex portion aggregate forming portion 100.

[0064] The method for forming the main recessed portion 130 and the sub-recessed portion 140 is not limited, but laser processing that irradiates the inner surface 12a of the side plate 12 to locally remove the inner surface 12a is preferred as the forming method. As the laser processing, for example, removal processing using pulsed fiber laser can be adopted. As the conditions for this laser processing, laser processing with a center wavelength of 1080 nm, an average output of 100 W or more and 300 W or less, and a laser spot diameter of about 0.05 mm is preferred.

[0065] When vulcanizing and forming the tire 1 using the tire forming die 10, uncured rubber is filled into the plurality of convex portion aggregate forming recesses 110 in the convex portion aggregate forming portion 100, and the rubber is vulcanized, thereby forming a plurality of convex portion aggregates 20. That is, the rubber filled in the main recessed portion 130 is formed into the main cone 30, and the rubber filled in the sub-recessed portion 140 is formed into the sub-cone 40. Thus, as Figure 3 and Figure 4 shown, a plurality of convex portion aggregates 20 arranged in the first arrangement pattern 21 are formed in the pattern region 7 of the sidewall 3.

[0066] When light is incident on the pattern region 7 in which a plurality of convex portion aggregates 20 are arranged as described above, the light is reflected by the side surface 31 of the main cone 30 and the side surface 41 of the sub-cone 40 of the convex portion aggregate 20. The light reflected in this way is reflected again by the side surfaces 31 and 41 of the surrounding main cones 30 and sub-cones 40. Such reflections occur between the main cones 30, between the sub-cones 40, and between the main cone 30 and the sub-cone 40. As a result, the light incident on the pattern region 7 gradually attenuates and is absorbed. When visually recognizing such a pattern region 7, the pattern region 7 is visually recognized as darker than the outer surface 3a of the sidewall 3 of the reflected light around the pattern region 7.

[0067] In the above-described embodiment, the plurality of sub-cones 40 are closely arranged by increasing the number of their circumferential arrangements, and thus can form a ring-shaped convex portion.

[0068] Figure 8 and Figure 9 are diagrams schematically showing the convex portion aggregate 20 having such a formed ring-shaped convex portion 60. Figure 8 is a perspective view. Figure 9 is Figure 8 a view in the IX direction. The ring-shaped convex portion 60 is arranged concentrically with the main cone 30 so as to surround the main cone 30 on the surface 7a of the pattern region. The ring-shaped convex portion 60 is configured as the second convex portion of the present disclosure in the same manner as the sub-cone 40.

[0069] Figure 10 and Figure 11FIG. is an example of a convex portion assembly 20 in which an annular convex portion 60 formed by a plurality of sub-cones 40 is disposed around a main cone 30 as a second convex portion configuration of the present disclosure. Figure 10 It is a perspective view. Figure 11 It is Figure 10 the XI-direction view of. As Figure 10 and Figure 11 shown, the annular convex portion 60 is formed by arranging a plurality of sub-cones 40 closely adjacent to each other in the circumferential direction around the main cone 30. The bases 35 and the front portions 36 of a pair of adjacent sub-cones 40 in the circumferential direction overlap each other, and the tops 42 are close to each other. The annular top 61 of the annular convex portion 60 has an uneven shape in which the unevenness is continuously annular by a plurality of adjacent tops 42 arranged in the circumferential direction. By having such an uneven shape, the reflection of light generated at the top 61 of the annular convex portion 60 is complicated. Thereby, the absorption effect of the light incident on the pattern area 7 is promoted.

[0070] As Figure 5 shown, the height h2 of each sub-cone 40 of the embodiment from the pattern area surface 7a is smaller than the height h1 of the main cone 30 from the pattern area surface 7a. Therefore, the height of the annular convex portion 60 from the pattern area surface 7a is also smaller than the height of the main cone 30 from the pattern area surface 7a.

[0071] The above-described first arrangement pattern 21 is an example of an arrangement pattern of a plurality of convex portion assemblies 20. Figure 12 And Figure 13 show a state in which a plurality of convex portion assemblies 20 are arranged on the pattern area surface 7a through a second arrangement pattern 22 different from the first arrangement pattern 21. Figure 12 It is a perspective view. Figure 13 It is a top view and is Figure 12 the XIII-direction view of. Figure 14 It is an enlarged top view of a plurality of convex portion assemblies arranged in the second arrangement pattern.

[0072] As Figure 12 and Figure 13 shown, in the second arrangement pattern 22, a plurality of convex portion assemblies 20 similar to the convex portion assembly 20 shown in Figure 3 and Figure 4 shown are linearly arranged at equal intervals in the first direction F1. As Figure 14As shown, in a pair of convex portion aggregates 20 adjacent in the first direction F1, the main cones 30 approach each other, and their first slope portions 37 partially overlap each other. That is, the pattern region 7 has a first overlapping portion 51 where the first slope portions 37 of multiple main cones 30 overlap each other. In this second arrangement pattern 22, multiple main cones 30 are partially overlapped and linearly arranged in the first direction F1, and multiple sub-cones 40 are arranged around these multiple main cones 30 so as to surround these multiple main cones 30. The adjacent second slope portions 47 of the multiple sub-cones 40 partially overlap each other.

[0073] According to the embodiments described above, the following effects are achieved.

[0074] (1) The tire 1 of the embodiment has a pattern region 7 on a part of the outer surface 3a of the tire side 3, and the pattern region 7 is provided in a state where it can be visually recognized as a part different from the periphery of this part. Among them, multiple convex portion aggregates 20 protruding from the surface 7a of the pattern region 7 are arranged in the pattern region 7. The convex portion aggregate 20 includes: a main cone 30 as a first convex portion, which has a first slope portion 37 continuous with the surface 7a of the pattern region 7; and multiple second convex portions, which are arranged around the main cone 30 and are arranged in such a way that at least a part of them overlaps with the first slope portion 37 of the main cone 30. In the embodiment, the second convex portion is a sub-cone 40.

[0075] The light incident on the pattern region 7 of the tire 1 is reflected by the side surface 31 of the main cone 30 and the side surface 41 of the sub-cone 40 of the convex portion aggregate 20, and the reflected light is reflected again by the side surfaces 31 and 41 of the surrounding main cones 30 and sub-cones 40. Such reflection of light is generated between the main cones 30, between the sub-cones 40, and between the main cone 30 and the sub-cone 40. As a result, the light incident on the pattern region 7 gradually attenuates and is absorbed. When visually recognizing such a pattern region 7, the pattern region 7 is visually recognized as darker than the outer surface 3a of the tire side 3 where the reflected light of the periphery of the pattern region 7 is located. By arranging multiple convex portion aggregates 20, the reflection of light is caused complexly, and thus the black density of the pattern region 7 is increased compared with the past, and high contrast is achieved. By arranging the sub-cones 40 in such a way that they overlap with the first slope portion 37 of the main cone 30, in the convex portion aggregate 20, the main cone 30 and the sub-cone 40 are close to each other and the density is increased, so the absorption effect of the light incident on the pattern region 7 is promoted, and high contrast accompanied by an increase in black density is achieved.

[0076] (2) Based on the tire 1 in the above (1) of the embodiment, it is also possible that the sub-cones 40 as multiple second convex portions are arranged in a form that surrounds the main cone 30.

[0077] Thus, the probability that the light radially reflected from the main cone 30 reaches each sub-cone 40 and is reflected by these sub-cones 40 increases. Therefore, the number of repetitions of light reflection increases, and the light reflection becomes more complex. As a result, the absorption of the light incident on the pattern area 7 is promoted, and high contrast accompanied by an increase in black density is achieved.

[0078] (3) Based on the tire 1 of the above (1) and (2) in the embodiment, preferably, the second convex portion is a sub-cone 40, and three or more of these sub-cones 40 are arranged around the main cone 30.

[0079] The second convex portion is composed of the sub-cone 40 that is a cone together with the main cone 30, whereby the light reflection can be made more complex. Therefore, the absorption of the light incident on the pattern area 7 is promoted, and high contrast accompanied by an increase in black density is achieved.

[0080] (4) Based on the tire 1 of the above (3) in the embodiment, preferably, the height of the sub-cone 40 from the surface 7a of the pattern area 7 is smaller than the height of the main cone 30 from the surface 7a of the pattern area 7.

[0081] Compared with the case where the heights of the main cone 30 and the sub-cone 40 are equal, when the height of the sub-cone 40 is smaller than the height of the main cone 30, the concavo-convex shape of the surface shape of the convex portion aggregate 20 becomes more complex. As a result, the light reflection can be made more complex, so the absorption of the light incident on the pattern area 7 is promoted, and high contrast accompanied by an increase in black density is achieved.

[0082] (5) Based on the tire 1 of the above (3) and (4) in the embodiment, preferably, each of the plurality of sub-cones 40 has a second slope portion 47, and adjacent sub-cones 40 have a second overlapping portion 52 where the second slope portions 47 overlap each other.

[0083] As a result, the density of the plurality of sub-cones 40 constituting the convex portion aggregate 20 increases and the number increases, so the absorption of the light incident on the pattern area 7 is further promoted. As a result, high contrast accompanied by an increase in black density can be further achieved.

[0084] (6) Based on the tire 1 of the above (1) to (5) in the embodiment, the second convex portion may be an annular convex portion 60 arranged to surround the main cone 30.

[0085] Thus, the probability that the light radially reflected from the main cone 30 reaches the annular convex portion 60 and is reflected by the annular convex portion 60 increases. Therefore, the number of repetitions of light reflection increases, and the light reflection becomes more complex, promoting the light absorption effect. As a result, high contrast accompanied by an increase in black density can be further achieved.

[0086] (7) Based on the tire 1 in the above (6) of the embodiment, preferably, the height of the annular convex portion 60 from the surface 7a of the pattern region 7 is smaller than the height of the main cone 30 from the surface 7a of the pattern region 7.

[0087] Compared with the case where the heights of the main cone 30 and the annular convex portion 60 are equal, when the height of the annular convex portion 60 is smaller than the height of the main cone 30, the concavo-convex shape of the surface shape of the convex portion aggregate 20 becomes more complicated. Thereby, the reflection of light can be made more complicated, so that the absorption effect of the light incident on the pattern region 7 is promoted, and high contrast accompanied by an increase in black density is achieved.

[0088] (8) Based on the tire 1 in the above (6) or (7) of the embodiment, preferably, the top 61 of the annular convex portion 60 has a concavo-convex shape in which the concavities and convexities are continuously annular.

[0089] Thereby, the reflection of light generated at the top 61 of the annular convex portion 60 can be made more complicated, so that the absorption effect of the light incident on the pattern region 7 is promoted, and high contrast accompanied by an increase in black density is achieved.

[0090] (9) Based on the tire 1 in the above (1) to (8) of the embodiment, it may be that the pattern region 7 is in a form of a first overlapping portion 51 in which the first slope foot portions 37 having a plurality of main cones 30 overlap each other.

[0091] Thereby, the main cones 30 of the respective convex portion aggregates 20 approach each other and the density increases, so that the absorption effect of the plurality of main cones 30 on light is promoted, and high contrast accompanied by an increase in black density is achieved.

[0092] (10) The tire forming die 10 of the embodiment is used to form the tire 1 in the above (1) to (9), wherein the tire forming die includes a convex portion aggregate forming portion 100 including a plurality of main concave portions 130 and sub-concave portions 140 corresponding to the plurality of convex portion aggregates 20.

[0093] Through the plurality of main concave portions 130 and sub-concave portions 140 included in the convex portion aggregate forming portion 100 of the tire forming die 10, a plurality of convex portion aggregates 20 that achieve high contrast accompanied by an increase in black density are formed in the pattern region 7. Thereby, the tire 1 formed by using the tire forming die 10 can improve the design effect and appearance.

[0094] The embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and even if it is deformed, improved, etc. within the range capable of achieving the object of the present invention, it is included in the scope of the present invention.

[0095] For example, the plurality of convex portion aggregates 20 may also be arranged irregularly instead of being arranged in a specific arrangement pattern like the first arrangement pattern 21 and the second arrangement pattern 22.

[0096] The main cones 30 and the sub - cones 40 constituting the convex portion aggregate 20 are conical in shape, but either one or both of them may be in the shape of a multi - pyramid. In addition, the main cones 30 and the sub - cones 40 are second - order conical shapes with a changing inclination angle of the side surface, but either one or both of them may be multi - order conical shapes of the third order or higher. On the contrary, they may also be simple conical shapes with an unchanging inclination angle of the side surface.

[0097] The main cones 30 and the sub - cones 40 of the embodiment are straight cones with the central axis perpendicular to the surface 7a of the pattern area, but either one or both of them may be oblique cones with the central axis inclined with respect to the surface 7a of the pattern area. In one convex portion aggregate 20, the plurality of sub - cones 40 may include both straight cones and oblique cones. In the plurality of convex portion aggregates 20, the main cones 30 may be straight cones or oblique cones. Also, the main cones 30 and the sub - cones 40 may be oblique cones including an undercut shape, and this undercut shape includes a portion where a part of the side surface is inclined at an acute angle with respect to the surface 7a of the pattern area.

[0098] In the plurality of convex portion aggregates 20, the height h1, the bottom surface 33, and the apex angle (represented by Figure 5 θ) of the main cone 30 may be uniform or non - uniform respectively. In one convex portion aggregate 20, the height h1, the bottom surface 33, and the apex angle (represented by Figure 5 θ) of the plurality of sub - cones 40 may be uniform or non - uniform respectively.

[0099] The height h1 of the main cone 30 and the height h2 of the sub - cone 40 may be the same, or conversely, the height h1 of the main cone 30 may be smaller than the height h2 of the sub - cone 40 compared to the above - mentioned embodiment. The area of the bottom surface 33 of the main cone 30 and the area of the bottom surface 43 of the sub - cone 40 may be the same, or conversely, the area of the bottom surface 33 of the main cone 30 may be smaller than the area of the bottom surface 43 of the sub - cone 40. The apex angle of the main cone 30 and the apex angle of the sub - cone 40 may be the same or different.

[0100] The overlapping amounts of the plurality of overlapping portions 51 where the first slope foot portions 37 of the main cone 30 overlap each other may be uniform or non - uniform. The overlapping amounts of the plurality of overlapping portions 52 where the second slope foot portions 47 of the sub - cones 40 overlap each other may be uniform or non - uniform. The overlapping amounts of the plurality of third overlapping portions 53 where the first slope foot portions 37 of the main cone 30 overlap with the second slope foot portions 47 of the sub - cones 40 may be uniform or non - uniform.

[0101] In the above-described first alignment pattern 21, there is a non-overlapping portion 55 where the second slope portions 47 of the sub-cones 40 do not overlap between the linearly arranged portions 21A adjacent in the second direction F2. However, the non-overlapping portion 55 may not be provided, and the second slope portions 47 of the plurality of sub-cones 40 also overlap each other in the second direction F2. When the non-overlapping portion 55 is not provided, almost all of the light reflection occurs on the surface of the convex portion aggregate 20. Therefore, compared with the case where the non-overlapping portion 55 is provided, the possibility of the light reflection being complicated is high, and thus it is preferred.

Claims

1. A tire comprising a pattern region on a portion of an outer surface of a sidewall, wherein the pattern region is provided in a state where it can be visually recognized as a portion different from the surroundings of the portion, wherein: A plurality of convex assembly bodies protruding from the surface of the pattern area are arranged in the pattern area, The convex portion assembly includes: a main cone as a first convex portion, which has a first slope foot portion continuous with the surface of the pattern area; and a plurality of second convex portions, which are arranged around the main cone and are arranged in a manner such that at least a portion thereof overlaps with the first slope foot portion of the main cone.

2. The tire according to claim 1, wherein: The plurality of second protrusions are arranged so as to surround the main cone.

3. The tire according to claim 1 or 2, wherein: The second convex portion is a sub-cone, and three or more of the sub-cones are arranged around the main cone.

4. The tire according to claim 3, wherein: A height of the sub-cone from the surface of the pattern area is smaller than a height of the main cone from the surface of the pattern area.

5. The tire according to claim 3, wherein: The plurality of sub-cones respectively have a second slope foot portion, and the adjacent sub-cones have a second overlapping portion where the second slope foot portions overlap each other.

6. The tire according to claim 1 or 2, wherein: The second convex portion is an annular convex portion arranged so as to surround the main cone.

7. The tire according to claim 6, wherein: A height of the annular convex portion from the surface of the pattern area is smaller than a height of the main cone from the surface of the pattern area.

8. The tire according to claim 6, wherein: The top of the annular convex portion has a concavo-convex shape in which the concavo-convexity is continuous in an annular shape.

9. The tire according to claim 1 or 2, wherein: The pattern area has a first overlapping portion where the first slope foot portions of a plurality of the main cones overlap with each other.

10. A tire forming mold for forming the tire according to claim 1 or 2, wherein: The tire forming mold includes a convex portion assembly forming portion including a plurality of concave portions corresponding to the plurality of convex portion assemblies.

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