Pneumatic tires

Abstract

To provide a pneumatic tire having an excellent visual effect.SOLUTION: A pneumatic tire 1 has patterns 30 provided on a surface of a side wall 10. In the pneumatic tire 1, the pattern 30 has a plurality of annular diagrams 31 which are longer in a tire circumferential direction CD than a tire radial direction RD. The plurality of annular diagrams 31 are different in size from one another, and form overlapping parts 32 which overlap each other at one ends in the tire circumferential direction CD, and a large annular diagram 31 is located outside a small annular diagram 31 so as to form isolation parts 33, 34 which are arranged at intervals on the other side of the tire circumferential direction CD and both sides of the tire radial direction RD.SELECTED DRAWING: Figure 2

Description

[Technical field]

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

[0002] 2. Description of the Related Art Pneumatic tires are known that have a pattern formed by arranging a plurality of ridges extending along the tire surface on the surface of a sidewall.

[0003] Many of the conventional patterns on the surface of the sidewall are made up of a number of linearly extending ridges arranged at equal intervals. In addition, as disclosed in Patent Document 1, a pattern with curved ridges arranged at equal intervals is also known. Either pattern enhances the design of the sidewall. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2014-180947 A Summary of the Invention [Problem to be solved by the invention]

[0005] Although various patterns have been proposed so far, there is a demand for revolutionary patterns that produce unprecedented visual effects.

[0006] Therefore, an object of the present invention is to provide a pneumatic tire that produces a visual effect. [Means for solving the problem]

[0007] The pneumatic tire of this embodiment is characterized in that, in a pneumatic tire having a pattern provided on the surface of a sidewall, the pattern has a plurality of annular figures that are longer in the tire circumferential direction than in the tire radial direction, and the plurality of annular figures are different sizes from one another, and form an overlapping portion that overlaps with each other at one end in the tire circumferential direction, and a larger annular figure is arranged outside a smaller annular figure so as to form separated portions arranged at intervals on the other side in the tire circumferential direction and on both sides in the tire radial direction. Effect of the Invention

[0008] In the present invention, by providing the above-mentioned features, contrast is improved in the tire circumferential direction, and a directional visual effect is produced. [Brief description of the drawings]

[0009] [Figure 1] FIG. 2 is a half cross-sectional view of a pneumatic tire taken in an axial direction. [Diagram 2] A pneumatic tire as seen from the axial direction of the tire in FIG. [Diagram 3] Enlarged view of the pattern [Figure 4] Cross-sectional view of a convex strip forming a ring shape [Diagram 5] Cross-sectional view of a convex strip forming a ring shape [Figure 6] Cross-sectional view of a convex strip forming a ring shape [Figure 7] Cross-sectional view of a convex strip forming a ring shape [Figure 8] Cross-sectional view of a convex strip forming a ring shape [Figure 9] Cross-sectional view of a convex strip forming a ring shape [Figure 10] FIG. 1 is a diagram showing a modified pneumatic tire viewed from the tire axial direction. [Figure 11] FIG. 1 is a diagram showing a modified pneumatic tire viewed from the tire axial direction. [Figure 12] FIG. 1 is a diagram showing a modified pneumatic tire viewed from the tire axial direction. [Figure 13] FIG. 1 is a diagram showing a modified pneumatic tire viewed from the tire axial direction. [Figure 14]FIG. 1 is a diagram showing a modified pneumatic tire viewed from the tire axial direction. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0011] The pneumatic tire 1 of the embodiment has a structure similar to that of a general radial tire, except for the structure of the sidewall. A cross-sectional structure of the pneumatic tire 1 of the embodiment is shown in Fig. 1. Note that Fig. 1 shows only half of the tire in the axial direction, and the actual pneumatic tire 1 is substantially symmetrical with respect to the center line C.

[0012] The pneumatic tire 1 has beads 9 on both axial sides of the tire. The bead 9 includes a bead core made of a steel wire wound in a circular shape, and a rubber bead filler provided radially outside the bead core.

[0013] One or two carcass plies 2 are laid across the beads 9 on both sides in the axial direction of the tire. The carcass ply 2 is a sheet-like member in which numerous ply cords arranged in a direction perpendicular to the tire circumferential direction are covered with rubber. The carcass ply 2 forms the framework of the pneumatic tire 1 between the beads 9 on both sides in the axial direction of the tire, and wraps the beads 9 by being folded back and wound up around the beads 9 from the inside to the outside in the axial direction of the tire. In addition, a rubber chafer 3 is provided at a location on the outside in the axial direction of the folded back portion 2a of the carcass ply 2.

[0014] Furthermore, one or more belts 4 are provided on the radially outer side of the carcass ply 2, and a belt reinforcing layer 5 is provided on the radially outer side of the belt 4. The belt 4 is a member made of many steel cords covered with rubber. The belt reinforcing layer 5 is a member made of many organic fiber cords covered with rubber. A tread rubber 6 is provided on the radially outer side of the belt reinforcing layer 5. The tread rubber 6 has many grooves formed therein to form a tread pattern.

[0015] In addition, sidewall rubber 7 is provided on both sides of the carcass ply 2 in the tire axial direction. The tread rubber 6 and the sidewall rubber 7 overlap at the buttresses, but either the tread rubber 6 or the sidewall rubber 7 may overlap on the tire surface side. The radially inner portion of the sidewall rubber 7 extends close to the bead 9 and covers a part of the rubber chafer 3. In this embodiment, the sidewall 10 refers to not only the portion of the sidewall rubber 7 that appears on the tire surface, but also the entire area that can be seen when the pneumatic tire 1 is viewed from the tire axial direction.

[0016] In addition, a sheet-like inner liner 8 made of rubber with low air permeability is attached to the inside of the carcass ply 2. In addition to these components, components such as an underbelt pad and a chafer are provided according to the functional needs of the tire.

[0017] As shown in Figs. 1 and 2, a decorative region 11 and a band-like region 40 are provided on at least one of the sidewalls 10 on both axial sides of the tire.

[0018] The decorative region 11 is an annular region centered on the tire rotation axis. The decorative region 11 is a region of a constant width sandwiched between a small-diameter circular inner diameter side line 12 and a large-diameter circular outer diameter side line 13. The inner diameter side line 12 and the outer diameter side line 13 may be lines formed by concaves, convexities, or steps on the tire surface, or may be imaginary lines that do not actually exist. The width HA of the decorative region 11 in the tire radial direction RD is 5% to 60% (preferably 10% to 35%) of the tire cross-sectional height H (the length in the tire radial direction RD from the inner diameter end of the bead core to the outer diameter surface of the pneumatic tire 1).

[0019] The location of the decorative area 11 in the tire radial direction RD is a location including the position of the maximum width of the pneumatic tire 1. Here, the position of the maximum width of the pneumatic tire 1 refers to the position where the length in the tire axial direction from the surface of one sidewall 10 in the tire axial direction to the surface of the other sidewall 10 in the tire axial direction is the longest.

[0020] The decorative region 11 may be provided on the sidewall 10 so as to include a place where a step is likely to appear on the surface of the sidewall 10. The place where a step is likely to appear on the surface of the sidewall 10 is typically a place at the end of a tire constituent member, such as a place where the interface between the tread rubber 6 and the sidewall rubber 7 appears on the tire surface or a place that overlaps with an end of the turned-up portion 2a of the carcass ply 2 in the tire width direction.

[0021] 2, the annular decorative area 11 has two opposing mark areas 11a each having a mark 16 formed therein. The annular decorative area 11 has two opposing pattern areas 11b each having a pattern 30 formed therein, each of which is sandwiched between the two mark areas 11a.

[0022] In order to provide a sufficient distance between the adjacent mark region 11a and pattern region 11b, the minimum value of the distance LB between the end of the mark region 11a and the end of the pattern region 11b (the length in the tire circumferential direction CD from the mark 16 provided in the mark region 11a to the end of the pattern 30 provided in the pattern region 11b) is set to 3 mm. Also, in order to ensure a sufficient area for the pattern 30 provided in the decorative region 11, the maximum value of the distance LB between the mark region 11a and the pattern region 11b is set to 60% of the length LA in the tire circumferential direction CD of the mark region 11a (the distance between the marks 16 provided at both ends of the mark region 11a in the tire circumferential direction).

[0023] In the marking area 11a, one or more marks 16 are formed side by side in the tire circumferential direction CD. The marks 16 are made up of letters, numbers, symbols, figures, etc., and indicate various information such as the tire manufacturer, brand, type, size, etc. These marks 16 constituting the marking area 11a are formed with a border of concave or convex lines.

[0024] In the pattern region 11b, a plurality of patterns 30 are formed side by side in the tire circumferential direction CD. As shown in Fig. 2 and Fig. 3, the pattern 30 is formed by combining a plurality of annular figures 31 having different sizes. Preferably, the pattern 30 is formed by combining five or more annular figures 31.

[0025] Each of the multiple annular figures 31 constituting the pattern 30 is an annular figure that is longer in the tire circumferential direction CD than in the tire radial direction RD. In this embodiment, the multiple annular figures 31 are substantially elliptical.

[0026] The ratio of the length in the tire radial direction RD to the length in the tire circumferential direction CD of the plurality of annular figures 31 is preferably 0.5 to 0.8. The length in the tire radial direction RD of the largest annular figure 31 among the plurality of annular figures 31 is preferably 50% to 95% of the width HA of the decorative area 11 in the tire radial direction RD.

[0027] The multiple annular figures 31 constituting the pattern 30 are arranged so that larger annular figures 31 surround smaller annular figures 31 in sequence without intersecting with each other except at overlapping parts 32. In other words, the multiple annular figures 31 are arranged so as to form an overlapping part 32 where they overlap with each other at one end in the tire circumferential direction CD, form first separated parts 33 arranged at intervals on the other side in the tire circumferential direction CD, and form second separated parts 34 arranged at intervals on both sides in the tire radial direction RD.

[0028] The plurality of annular figures 31 are arranged at a first spaced portion 33 provided on the other side in the tire circumferential direction CD. To Alternatively, the annular figures 31 may be arranged so as to be spaced apart at equal intervals from the innermost annular figure 31 toward the outermost annular figure 31. A specific value of the interval between the annular figures 31 in the first separated portion 33 (the distance from the farthest position on the annular figure 31 to the overlapping portion 32) is, for example, 0.6 mm or more and 2.4 mm or less.

[0029] Each of the multiple ring-shaped figures 31 is formed by connecting a groove recessed into the surface of the sidewall or a ridge protruding from the surface of the sidewall in a ring shape. When the ring-shaped figure 31 is formed from the ridges 20, the cross-sectional shape of the ridges 20 in a direction perpendicular to the longitudinal direction may be a semicircle as shown in FIG. 4, a semicircle and a straight line below as shown in FIG. 5, a triangle as shown in FIG. 6, a triangle with rounded apexes as shown in FIG. 7, a trapezoid as shown in FIG. 8, or a rectangle as shown in FIG. 9. Here, the triangle with rounded apexes as shown in FIG. 7 is a type of triangle. Although not shown, these cross-sectional shapes may be slightly modified, for example, a sawtooth shape obtained by deforming the triangle in FIG. 6 by tilting it. The line drawn as the ring-shaped figure 31 in FIG. 2 and FIG. 3 is the center line of the ridges 20 in the width direction (the line indicated by T in FIG. 4 to FIG. 9).

[0030] In the ridges 20 having any of the cross-sectional shapes shown in Figs. 4 to 9, the height H1 of the ridges 20 is 0.1 mm or more and 0.8 mm or less (preferably 0.1 mm or more and 0.4 mm or less). In addition, in the ridges 20 having any of the cross-sectional shapes, the width W1 of the ridges 20 is 0.1 mm or more and 1.0 mm or less. The ridges 20 can be formed by a mold used during vulcanization molding. The ridges 20 can be formed by various processes such as mechanical processing and laser processing. Small ridges 20 having a height H1 of about 0.1 mm to 0.2 mm and a width W1 of about 0.1 mm to 0.2 mm can be formed by a mold in which fine irregularities are formed by laser processing.

[0031] 4 and 5 has a radius R, the length H2 of the straight line of the convex rib 20 having a cross-sectional shape as shown in Fig. 5, which is composed of a semicircle and a straight line, is (height H1 of the convex rib 20) - (radius R of the semicircle). In the convex rib 20 having a trapezoidal cross-section as shown in Fig. 8, the length W2 of the upper base is 20% to 50% of the length of the lower base (i.e., width W1 of the convex rib 20).

[0032] In this embodiment, as shown in Fig. 2, a plurality of patterns 30 are provided in the decorative region 11 at intervals in the tire circumferential direction CD. All of the patterns 30 are provided in the decorative region 11 such that overlapping portions 32 are located on one side of the tire circumferential direction CD. The plurality of patterns 30 are preferably arranged such that one pattern 30 is located at an opposing position across the tire rotation axis.

[0033] The band-shaped region 40 is an annular region provided adjacent to the outer periphery of the decorative region 11. The band-shaped region 40 is provided with a plurality of ridges 41 protruding from the outer surface of the sidewall 10. In one embodiment, the plurality of ridges 41 are equally spaced apart in the tire circumferential direction CD at intervals of 0.3 to 1.0 mm. The band-shaped region 40 may be provided in a portion of the tire circumferential direction CD, but in this example, it is provided over the entire circumference in the tire circumferential direction CD. Therefore, the band-shaped region 40 is formed in an annular shape adjacent to the outer side of the decorative region 11 and surrounding it over the entire circumference. The dimension HC (see FIG. 1) of the band-shaped region 40 in the tire radial direction RD is preferably 5 mm to 12 mm.

[0034] Providing such a belt-like region 40 can suppress unevenness and bareness at the interface between the tread rubber 6 and the sidewall 10. In addition, the provision of the protrusions 41 has a light attenuation effect, forming a black belt-like region 40, which makes the decorative region 11 stand out.

[0035] Similar to the decorative region 11, such a band-like region 40 may be provided on the sidewall 10 so as to include locations where steps are likely to appear on the surface of the sidewall 10, such as locations where the interface between the tread rubber 6 and the sidewall rubber 7 appears on the tire surface, locations where the end of the turned-up portion 2a of the carcass ply 2 overlaps in the tire width direction, locations where the end of the belt 4 overlaps in the tire width direction, and other tire constituent members. A parting line 42, which is a dividing line between the tread mold and the sidewall mold in the tire mold, may be formed at the boundary portion on the outer side in the tire radial direction of the band-like region 40.

[0036] In the pneumatic tire 1 of this embodiment, the sidewall 10 is provided with a pattern 30 in which a plurality of annular figures 31 are arranged at intervals on the other circumferential side and on both radial sides of the tire, overlapping at one circumferential end of the tire, creating a contrast (light and dark) with a sense of depth from the first separated portion 33 to the overlapping portion 32, creating a novel visual effect.

[0037] Furthermore, by arranging the multiple annular figures 31 at equal intervals in the first separated portion 33 and the second separated portion 34, a smoother sense of depth is created in the pattern 30. Furthermore, by providing the multiple annular figures 31 so that the intervals between the annular figures 31 gradually increase from the innermost annular figure 31 toward the outermost annular figure, the sense of depth created from the first separated portion 33 toward the overlapping portion 32 can be emphasized.

[0038] Furthermore, when the pneumatic tire 1 is a tire with a specified rotation direction, all of the patterns 30 provided on the surface of the sidewall 10 may be arranged so that the overlapping portions 32 are located forward in the rotation direction RF (see FIG. 2). By arranging the patterns 30 in this manner, it is possible to indicate the rotation direction while providing an excellent design.

[0039] (Example of change) The above-described embodiment is presented as an example and is not intended to limit the scope of the invention. This novel embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention.

[0040] For example, the shape of the multiple annular figures 31 is not limited to the approximately elliptical shape of the above embodiment. Any ring-shaped figure may be used as long as it is longer in the tire circumferential direction CD than in the tire radial direction RD when viewed from a direction perpendicular to the surface of the sidewall 10. Among such ring-shaped figures, a preferred shape is a shape called an oval. An oval is a closed ring-shaped shape that is mainly composed of curves (for example, more than half of the total length of the lines forming the outline of the ring-shaped figure 31 are curved). In addition to the elliptical shape of the above embodiment, ovals also include oval, perfect circle, egg shape, etc. In addition, an oval also includes a closed curve formed by the intersection of the surface of a cone with a plane that completely crosses the cone.

[0041] In the above embodiment, all the patterns 30 are provided on the surface of the sidewall 10 so that the overlapping portions 32 are located on one side in the tire circumferential direction CD, but the overlapping portions 32 can be arranged in various ways.

[0042] For example, as shown in Fig. 10, the pattern 30 may be arranged so that the overlapping portion 32 faces one of the mark areas 11a (the mark area 11a on the left side in Fig. 10), or as shown in Fig. 11, the pattern 30 may be arranged so that the overlapping portion 32 faces the adjacent mark area 11a. Also, as shown in Figs. 12 and 13, the pattern 30 may be arranged so that the orientation of the overlapping portion 32 alternates in the tire circumferential direction CD. As shown in Figs. 10, 11, and 12, when a pair of patterns 30 adjacent to the mark area 11a in the tire circumferential direction CD are arranged so that the overlapping portion 32 faces the mark area 11a, the consumer's gaze is likely to be directed to the mark area 11a sandwiched between the overlapping portions 32, and the mark 16 provided in the mark area 11a can be emphasized.

[0043] In addition, since many annular figures 31 are provided in one pattern 30, some of the larger annular figures 3 1 is 14, the pattern 30 may not fit within the decorative area 11 and may be interrupted. In such a case, it is preferable to provide a large number of annular figures 31 in one pattern 30 so that five or more annular figures 31 fit within the decorative area 11.

[0044] Further, in the above embodiment, two pattern regions 11b are provided for one sidewall 10, but one or three or more pattern regions 11b may be provided for one sidewall 10.

[0045] Furthermore, in the above embodiment, four patterns 30 are provided in one pattern region 11b, but any number of patterns 30 may be provided in one pattern region 11b.

[0046] In this specification, the above dimensions are those in a normal unloaded state with the pneumatic tire mounted on a normal rim and inflated to the normal internal pressure. The normal rim is the "standard rim" in the JATMA standard, and the "Measuring Rim" in the TRA and ETRTO standards. The normal internal pressure is the "maximum air pressure" in the JATMA standard, the "maximum value" described in the "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES" in the TRA standard, or the "INFLATION PRESSURE" in the ETRTO standard. However, for passenger car tires, the normal pressure is 180 kPa, but for tires marked as Extra Load or Reinforced, the normal pressure is 220 kPa.

[0047] In addition, the various numerical ranges described in the specification can be arbitrarily combined with their upper and lower limits, and all such combinations are considered to be preferred numerical ranges described in the specification. In addition, a numerical range described as "X to Y" means from X to Y. [Explanation of symbols]

[0048] 1...pneumatic tire, 4...belt, 6...tread rubber, 7...sidewall rubber, 9...bead, 10...sidewall, 11...decorative area, 11a...marking area, 11b...pattern area, 12...inner diameter side line, 13...outer diameter side line, 16...mark, 30...pattern, 31...annular figure, 32...overlapping portion, 33...first spaced portion, 34...second spaced portion

Claims

1. In a pneumatic tire having a pattern on the surface of the sidewall, The pattern has a plurality of annular figures that are longer in the tire circumferential direction than in the tire radial direction, The multiple annular figures are different in size from one another, and larger annular figures are arranged outside smaller annular figures so as to form an overlapping portion at one end in the tire circumferential direction and separate portions arranged at intervals on the other side in the tire circumferential direction and on both sides in the tire radial direction.

2. 2. The pneumatic tire of claim 1, wherein said annular shape is an oval shape.

3. The pneumatic tire according to claim 1 or 2, wherein the plurality of annular figures are provided at equal intervals in the separated portion on the other circumferential side of the tire.

4. The pneumatic tire according to claim 2 , wherein a ratio of a length in a radial direction of the tire to a length in a circumferential direction of the annular figure is 0.5 or more and 0.8 or less.

5. The plurality of annular figures are formed of grooves recessed into a surface of the sidewall or ridges protruding from a surface of the sidewall, The pneumatic tire according to any one of claims 1 to 4, wherein the cross-sectional shape of the plurality of annular figures is a triangle, a trapezoid, or a semicircle.

6. A mark area having one or more marks and a pair of the patterns are provided on a surface of the sidewall, The pneumatic tire according to any one of claims 1 to 5, wherein a pair of the patterns are arranged on both sides of the mark area in the tire circumferential direction, with the overlapping portion facing the mark area.

7. The pneumatic tire has a designated rotation direction, The pneumatic tire according to any one of claims 1 to 5, wherein the pattern is provided on the surface of the sidewall so that the overlapping portion is located on a front side in a rotational direction.

8. The pneumatic tire according to any one of claims 1 to 7, wherein a region in which a plurality of ridges extending in the tire radial direction are arranged at equal intervals in the tire circumferential direction is provided on the sidewall, radially outward of the decorative region in which the annular figure is provided, the region having a dimension in the tire radial direction of 5 mm or more and 12 mm or less.

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