JP2023032823A - pneumatic tire - Google Patents

Abstract

To provide a pneumatic tire in which visual effects are generated.SOLUTION: A pneumatic tire 1 is provided with patterns on each of side walls 10. The side wall 10 of the pneumatic tire 1 comprises: a plurality of reference points 22 arranged like a spiral; and a plurality of circular patterns 20 each forming a circle centered on the reference point 22. Among the circular patterns 20, the farther on a spiral outer side, each reference point 22 thereof is located, the larger, each radius thereof is. Each circular pattern 20 centered on the reference point 22 on a spiral inner side, is configured to inscribe each circular pattern 20 centered on the reference point 22 on an immediately outer side.SELECTED DRAWING: Figure 2

Description

The present invention relates to pneumatic tires.

For example, as described in Patent Document 1, a pneumatic tire having a pattern provided on the sidewall is known. The pattern is formed by lining up a large number of ridges.

Many of the conventional patterns are formed by arranging a large number of linearly extending ridges at regular intervals. Further, as disclosed in Japanese Patent Laid-Open No. 2002-200010, there is also known a ridge in which curved ridges are arranged at regular intervals. Both patterns enhance the design of the sidewall.

JP 2014-180947 A

By the way, although beautiful patterns are frequently proposed, epoch-making patterns that produce unprecedented visual effects are not often proposed.

Accordingly, an object of the present invention is to provide a pneumatic tire that produces a visual effect.

A pneumatic tire according to an embodiment is a pneumatic tire having a pattern on a sidewall, wherein the sidewall has a plurality of spirally arranged reference points and a circle centered at each of the reference points. A plurality of circular patterns are provided, and the circular pattern has a larger radius on the outer side of the spiral, and the circular pattern centered on the reference point on the inner side of the spiral is located on the outer side of the spiral. is inscribed in the circular pattern centered on the reference point.

The pneumatic tire of the embodiment produces a visual effect that gives a three-dimensional effect by providing the above features.

Fig. 3 is an axial half-sectional view of the pneumatic tire; The figure which looked at the decoration area|region of the sidewall from the tire axial direction. An enlarged view of a small pattern. Cross-sectional view of a ridge (when the cross-sectional shape is semicircular). A cross-sectional view of a ridge (when the cross-sectional shape is a semicircle and a straight line below it). Cross-sectional view of a ridge (when the cross-sectional shape is triangular). Cross-sectional view of a ridge (when the cross-sectional shape is a triangular shape with rounded vertices). Cross-sectional view of a ridge (when the cross-sectional shape is trapezoidal). Cross-sectional view of a ridge (when the cross-sectional shape is rectangular). Sectional drawing of the ridge in the contact position of two ridges. Sectional drawing of the ridge in the contact position of two ridges. Sectional drawing of the ridge in the contact position of two ridges. The figure which looked at the decoration area|region of the sidewall of the example of a modification from the tire axial direction. The figure which looked at the decoration area|region of the sidewall of the example of a modification from the tire axial direction. The figure which looked at the decoration area|region of the sidewall of the example of a modification from the tire axial direction. The figure which looked at the decoration area|region of the sidewall of the example of a modification from the tire axial direction. FIG. 4 is a partially enlarged view of a decorative region and its radially outer region;

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

In the pneumatic tire 1, bead portions 9 are provided on both sides in the tire axial direction. The bead portion 9 is composed of a bead core made of a circularly wound steel wire and a rubber bead filler provided radially outside the bead core.

One or two carcass plies 2 are laid over the bead portions 9 on both sides in the tire axial direction. The carcass ply 2 is a sheet-like member in which a large number of ply cords arranged in a direction orthogonal to the tire circumferential direction are coated with rubber. The carcass ply 2 forms the skeleton shape of the pneumatic tire 1 between the bead portions 9 on both sides in the tire axial direction, and is folded back around the bead portions 9 from the inner side to the outer side in the tire axial direction and rolled up to form the bead portions 9 . wrapping the In addition, a rubber chafer 3 is provided on the outside of the folded portion 2a of the carcass ply 2 in the axial direction of the tire.

One or more belts 4 are provided outside the carcass ply 2 in the tire radial direction, and a belt reinforcing layer 5 is provided outside the belt 4 in the tire radial direction. The belt 4 is a member made by coating a large number of steel cords with rubber. The belt reinforcing layer 5 is a member made by coating a large number of organic fiber cords with rubber. A tread rubber 6 is provided outside the belt reinforcing layer 5 in the tire radial direction. The tread rubber 6 is provided with a large number of grooves to form a tread pattern.

Sidewall rubbers 7 are provided on both sides of the carcass ply 2 in the tire axial direction. Although the tread rubber 6 and the sidewall rubber 7 overlap at the buttress, either the tread rubber 6 or the sidewall rubber 7 may overlap on the tire surface side. A portion of the sidewall rubber 7 on the inner side in the tire radial direction extends close to the bead portion 9 and partially covers the rubber chafer 3 . In this embodiment, the sidewall 10 is not only the portion where the sidewall rubber 7 appears on the tire surface, but also the entire visible range when the pneumatic tire 1 is viewed from the tire axial direction.

A sheet-like inner liner 8 made of rubber having low air permeability is attached to the inner side of the carcass ply 2 . In addition to these members, members such as an under-belt pad and a chafer are provided according to the functional needs of the tire.

As shown in FIG. 1, decoration regions 11 are provided on at least one of sidewalls 10 on both sides in the axial direction of the tire. As shown in FIG. 2, the decoration area 11 is in the form of an annulus centered on the tire rotation axis. The decorative region 11 is a region of 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, convexes, or steps on the tire surface, or may be virtual lines that do not actually exist. The width HA of the decorative region 11 in the tire radial direction is 5% or more and 60% or less (preferably 10%) of the tire section height H (the length in the tire radial direction from the inner diameter end to the outer diameter surface of the pneumatic tire 1). above 35%).

The location of the decoration region 11 in the tire radial direction 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 is the position where the length in the tire axial direction from the surface of the sidewall 10 on one side in the tire axial direction to the surface of the sidewall 10 on the other side in the tire axial direction is the longest. That is.

Further, in FIG. 1, the decorative region 11 is provided so as to include the portion where the interface between the tread rubber 6 and the sidewall rubber 7 appears on the tire surface. In this way, it is preferable that the decoration area 11 is provided on the surface of the sidewall 10 so as to include a place where a step is likely to appear. The place where the surface of the sidewall 10 is likely to have a step is typically the end part of the tire component. In addition to the location where the interface between the tread rubber 6 and the sidewall rubber 7 appears on the tire surface as described above, such typical locations include, for example, the wound-up end 2b of the carcass ply 2 (the folded back of the carcass ply 2). There is a place in the axial direction of the tire at the end of the portion 2a).

As shown in FIG. 2, labelings 15 are provided at two opposing locations of the annular decorative region 11, respectively. Patterns 14 are provided at two locations sandwiched between the two labelings 15, respectively. Thus, the labeling 15 and the pattern 14 are alternately arranged in the tire circumferential direction.

The minimum value of the interval LB between the labeling 15 and the pattern 14 (the length in the tire circumferential direction from the end of the labeling 15 to the end of the pattern 14) in order to provide a sufficient space between the adjacent labeling 15 and the pattern 14 is 3 mm. Further, in order to secure a sufficient area of the pattern 14, the maximum value of the interval LB between the labeling 15 and the pattern 14 is set to the length LA of the labeling 15 in the tire circumferential direction (from one end of the labeling 15 in the tire circumferential direction 60% of the length to the other end in the tire circumferential direction).

The labeling 15 is formed by arranging a plurality of letters 16 in the tire circumferential direction. Any of the manufacturer's name, product name, brand, etc. is displayed by these plural characters 16 . These characters 16 are shapes that can be clearly identified for the purpose of displaying the manufacturer's name or the like. Further, each character 16 is formed by being bordered by concave or convex lines.

As shown in FIGS. 2 and 3, pattern 14 includes a large number of ridges 20 . When viewed from a direction perpendicular to the surface of the sidewall 10, each ridge 20 has a perfect circular shape. A plurality of (preferably five or more) ridges 20 of different sizes are assembled to form one small pattern 25 . All the ridges 20 forming one small pattern 25 have different sizes.

In the small pattern 25, the smaller ridges 20 are arranged inside the ridges 20 that are larger (that is, have a larger radius). A smaller ridge 20 inscribes the larger ridge 20 immediately outside it. Inscribed circles mean that two circles share one point and one circle is inside the other circle. The pattern 14 is formed by arranging a plurality of such small patterns 25 in the tire circumferential direction. The length of the small pattern 25 in the tire radial direction (that is, the diameter of the largest ridge 20) is 50% or more and 95% or less of the width HA of the decorative region 11 in the tire radial direction.

Here, the ridges 20 protrude from the tire surface and extend long along the tire surface. This ridge 20 is also called a ridge. The cross-sectional shape in the direction orthogonal to the longitudinal direction of the ridge 20 includes a semicircle (Fig. 4), a shape consisting of a semicircle and a straight line below it (Fig. 5), a triangle (Fig. 6), and a triangle with rounded vertices. There are rectangular shapes (Fig. 7), trapezoids (Fig. 8), and rectangular shapes (Fig. 9). Here, a triangle with rounded vertices (FIG. 7) is a kind of triangle. Also, although not shown, a shape obtained by slightly deforming these cross-sectional shapes, for example, a sawtooth shape obtained by tilting the triangle shown in FIG.

The line drawn as the ridge 20 in FIGS. 2 and 3 is the center line in the width direction of the ridge 20 (the line indicated by T in FIGS. 4 to 9). Also, the radius and diameter of the ridges 20 are obtained based on the center line of the ridges 20 in the width direction. The radius and diameter of the ridge 20 are the radius and diameter of the perfect circle drawn by the ridge 20 .

The height H1 of the ridge 20 of any cross-sectional shape is 0.1 mm or more and 0.8 mm or less (preferably 0.1 mm or more and 0.4 mm or less). Moreover, the width W1 of the ridge 20 of any cross-sectional shape is 0.1 mm or more and 1.0 mm or less.

The ridges 20 can be formed by a mold used for vulcanization molding. Here, the ridges 20 having a small height H1 and width W1 can be formed by using a mold in which fine unevenness is formed by laser processing.

Further, if the radius of the semicircle in FIGS. 4 and 5 is R, the length H2 of the straight line of the ridge 20 having the shape of FIG. )−(radius R of semicircle). Moreover, in the trapezoidal ridge 20 of FIG. 8, the length W2 of the upper base is 20% or more and 50% or less of the length of the lower base (that is, the width W1 of the ridge 20).

By the way, one spiral reference line (not shown) is set in the above small pattern 25 . A plurality of reference points 22 (see FIG. 3) are set on the reference line. Since the reference line is spiral, the plurality of reference points 22 are arranged spirally. Note that the reference line and the reference point 22 are not actually formed in the decoration area 11 by irregularities or the like, but are imaginary. A ridge 20 is provided for each of these reference points 22 . Specifically, the centers of the circular ridges 20 are arranged at respective reference points 22 .

Here, the linear distance P (not shown) between two adjacent reference points 22 on the reference line increases toward the outside of the spiral drawn by the reference line (away from the center of the spiral). That is, considering three reference points 22a, 22b, and 22c (see FIG. 3) provided in order from the inner side of the spiral (closer to the center of the spiral) toward the outer side, the inner two reference points 22a, 22b A relationship of P1<P2 is established between a linear distance P1 between the two outer reference points 22b and 22c and a linear distance P2 between the two outer reference points 22b and 22c. However, P2 is preferably two times or less than P1.

The radius of the ridges 20 increases as the ridges 20 are centered on the outside of the spiral (the spiral drawn by the reference line). Then, of the two reference points 22 adjacent on the reference line, the ridge 20 centered on the reference point 22 on the inner side of the spiral (hereinafter referred to as the "inner ridge 20") and the same two reference points 22 ridges 20 (hereinafter referred to as "outer ridges 20") centering on reference points 22 on the outer side of the spiral are in contact with each other. However, the inner ridges 20 do not protrude outside the outer ridges 20 . That is, the inner ridge 20 is inscribed in the outer ridge 20 . In addition, for all the ridges 20 belonging to the same small pattern 25, the inner ridges 20 are inscribed with the outer ridges 20 thereof.

Here, contact means that the two ridges 20 overlap and integrate at the contact position as shown in FIG. 10, that the two ridges 20 partly overlap each other as shown in FIG. , means that there is no gap between the two ridges 20 .

When the linear distance between two reference points 22 adjacent on the reference line is P, the radius of the outer protrusion 20 among the protrusions 20 centered on these two reference points 22 is the same two reference points 22. It is preferably a value obtained by adding P to the radius of the inner ridge 20 among the ridges 20 at the center. When this preferable relationship is established, the inner ridge 20 is inscribed in the outer ridge 20 accurately.

As described above, since the reference points 22 that are the centers of the ridges 20 are arranged in a spiral, all the ridges 20 are arranged in a spiral. A smaller ridge 20 is located on the inner side of the spiral, and a larger ridge 20 is located on the outer side of the spiral. Further, as shown in FIG. 3, the contact points 23 between the inner protruding line 20 and the outer protruding line 20 are also arranged to draw a single spiral.

The diameter of the projection 20 having the smallest radius in the small pattern 25 (hereinafter referred to as "minimum projection 20a") is 10% or more and 50% or less of the width HA of the decoration region 11 in the tire radial direction. be. As a result, a sufficient number of ridges 20 are included in the decorative area 11. - 特許庁

At a location away from the contact point 23 between the inner ridge 20 and the outer ridge 20 (therefore, the location where the inner ridge 20 and the outer ridge 20 are apart), between the two ridges 20 Due to the presence of a wide flat surface, the light that hits it will have a specular reflection or a near-specular reflection. On the other hand, at the contact point 23 between the inner ridge 20 and the outer ridge 20, the incident light is diffusely reflected.

As a result, a place apart from the contact point 23 between the inner ridge 20 and the outer ridge 20 looks brighter, and the contact point 23 between the inner ridge 20 and the outer ridge 20 looks darker. Since the contact points 23 between the inner ridge 20 and the outer ridge 20 are spirally arranged as described above, it appears that there is a black spiral connecting the contact points 23 .

As shown in FIG. 2, the minimum ridge 20a is biased toward one side in the tire circumferential direction from the center of the small pattern 25 (that is, the center of the ridge 20 having the largest radius in the small pattern 25). . Here, "biased" means that the center of the smallest ridge 20a deviates from the center of the small pattern 25 in one direction. As shown in FIG. 2 , in the entire decoration area 11 , all of the smallest ridges 20 a are located on one side in the tire circumferential direction from the center of the small pattern 25 . The direction of the bias is indicated by arrow D in FIG.

When the decorative regions 11 are provided on both sides in the axial direction of the tire, such features of the ridges 20 are common to the decorative regions 11 on both sides in the axial direction of the tire.

As described above, in the pneumatic tire 1 of the embodiment, the sidewall 10 has a plurality of spirally arranged reference points 22 and a plurality of circular ridges 20 centering on the respective reference points 22. is provided. The radius of the ridges 20 centered on the reference point 22 on the outer side of the spiral is larger. It is inscribed in the ridge 20 with the point 22 as the center.

In this way, a plurality of circular ridges 20 having different sizes are provided, and small ridges 20 are provided inside the large ridges 20, so that the small pattern 25 made up of these ridges 20 has a three-dimensional effect. It creates a visual effect that makes you feel In addition, since the center of each ridge 20 is provided at the reference point 22 arranged in a spiral shape, a plurality of ridges 20 having different sizes are arranged in a spiral manner to form a conch. A visual effect that gives a three-dimensional effect is produced.

Also, the inner protruding line 20 is in contact with the outer protruding line 20, and the contact point 23 looks dark. Since the contact points 23 between the inner ridges 20 and the outer ridges 20 are spirally arranged, the small pattern 25 has a visual effect of black spirals.

In addition, the straight line distance between adjacent reference points 22 on the spiral increases toward the outside of the spiral. Since the ridges 20 are provided with respect to the reference points 22 arranged in this way, it is easy to recognize how the ridges 20 are spirally arranged.

In addition, in the entire decorative region 11, all the minimum ridges 20a are located on one side in the tire circumferential direction from the center of the small pattern 25. As shown in FIG. This creates a visual effect that all the small patterns 25 are oriented in the same direction in the tire circumferential direction.

The above embodiments are examples, and the scope of the invention is not limited to the above embodiments. Various modifications can be made to the above embodiments without departing from the scope of the invention.

For example, the linear distance between two adjacent reference points 22 on one spiral reference line may be equal between all reference points 22 in one small pattern 25 .

In addition, various patterns are possible as the direction of deviation of the minimum ridges 20 a in the small pattern 25 . For example, as shown in FIG. 13, all the minimum ridges 20a of the two patterns 14 may be biased toward the same labeling 15 (left labeling 15 in FIG. 13). Also, as shown in FIG. 14, all the minimum ridges 20a of the two patterns 14 may be biased towards the labeling 15 which is closer. Further, as in the pattern 14 in the upper part of FIG. 15, the directions of deviation of the minimum ridges 20a may alternate in the tire circumferential direction. In FIG. 15, two small patterns 25 having close minimum ridges 20a look like a pair of eyeballs. An arrow D in FIGS. 13 to 15 indicates the direction of deviation of the minimum ridge 20a.

Moreover, as a result of providing a large number of ridges 20 in one small pattern 25, the ridges 20b having a large radius may not fit within the decorative area 11 as shown in FIG. 16 and may be interrupted.

Moreover, although two patterns 14 are provided for one sidewall 10 in the above-described embodiment, one pattern 14 or three or more patterns 14 may be provided for one sidewall 10 .

Also, the pattern 14 may be formed by grooves instead of projections. Here, the concave streaks are recessed from the tire surface and extend long along the tire surface. Various cross-sectional shapes such as a triangle, a trapezoid, a rectangle, and a semicircle are possible as the cross-sectional shape in the direction perpendicular to the longitudinal direction of the groove. A ridge or groove that draws a circular line when viewed from a direction perpendicular to the surface of the sidewall 10 is referred to as a circular pattern.

Further, as shown in FIG. 17 , a band-shaped region 27 may be provided outside the decorative region 11 in the tire radial direction, in which a plurality of ridges 26 extending in the tire radial direction are arranged at regular intervals in the tire circumferential direction. . The plurality of ridges 26 are arranged at regular intervals of 0.3 mm or more and 1.0 mm or less in the tire circumferential direction. The band-shaped region 27 may be provided in a portion in the tire circumferential direction, or may be provided over the entire circumference in the tire circumferential direction. The band-shaped area 27 is adjacent to the outside of the decorative area 11 . The dimension in the tire radial direction of the band-shaped region 27 is preferably 5 mm or more and 12 mm or less.

By providing such a band-like region 27, it is possible to suppress interface unevenness and bareness between the members of the tread rubber 6 and the sidewall rubber 7. FIG. In addition, a black belt-like area is formed by the light attenuation effect resulting from the provision of the ridges 26, so that the decorative area 11 can be highlighted.

C... center line, 1... pneumatic tire, 2... carcass ply, 2a... folded portion, 2b... roll-up end, 3... rubber chafer, 4... belt, 5... belt reinforcing layer, 6... tread rubber, 7... side Wall rubber 8 Inner liner 9 Bead portion 10 Side wall 11 Decoration area 12 Inner diameter side line 13 Outer diameter side line 14 Pattern 15 Labeling 16 Letters 20 Protruding line , 20a...minimum ridge, 20b...large ridge, 22...reference point, 23...contact point, 25...small pattern, 26...ridge, 27...strip-shaped area

Claims (7)

In a pneumatic tire with a pattern on the sidewall,
The sidewall is provided with a plurality of spirally arranged reference points and a plurality of circular patterns that draw circles centered on the respective reference points,
The circular pattern has a larger radius as the reference point serving as the center thereof is located outside the spiral,
A pneumatic tire, wherein the circular pattern centered at the reference point inside the spiral is inscribed in the circular pattern centered at the reference point immediately outside. 2. The pneumatic tire according to claim 1, wherein a straight line distance between adjacent reference points on the spiral becomes larger on the outer side of the spiral. 2. The pneumatic tire according to claim 1, wherein linear distances between said adjacent reference points on said spiral are equal intervals. When the linear distance between two reference points adjacent on the spiral is P, the radius of the circular pattern centered on the outer reference point on the spiral among the two reference points is two The pneumatic tire according to any one of claims 1 to 3, which is a value obtained by adding P to the radius of the circular pattern centered at the inner reference point in the spiral among the reference points. The pneumatic tire according to any one of claims 1 to 4, wherein the cross-sectional shape of the circular pattern is a shape including triangle, trapezoid, rectangle or semicircle. In the sidewall, a region in which a plurality of ridges extending in the tire radial direction are arranged at regular intervals in the tire radial direction outside the decorative region in which the circular pattern is provided, in the tire radial direction The pneumatic tire according to any one of claims 1 to 5, wherein a region having a dimension of 5 mm or more and 12 mm or less is provided. The pneumatic tire according to any one of claims 1 to 6, wherein the circular pattern is a ridge protruding from the tire surface.

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