JP6034837B2 - Pneumatic tire - Google Patents

Description

  The present invention relates to a pneumatic tire in which a decorative pattern is formed on the surface of a sidewall portion.

  Generally, the sidewall portion of a pneumatic tire is covered with a small thickness of rubber. For this reason, local irregularities called bulges and dents are likely to appear on the surface of the sidewall due to the seam of the carcass that is the internal structural material of the tire, residual air, and the like.

  Conventionally, in order to make such unevenness inconspicuous, a pneumatic tire in which a decorative pattern is formed on the surface of a sidewall portion has been proposed (for example, Patent Document 1 below). Such a decorative pattern is also called a “serration pattern”, for example, and is formed by repeatedly arranging a vertical line pattern having a tire radial direction component in the tire circumferential direction.

Japanese Unexamined Patent Publication No. 07-164831

  However, the conventional decorative pattern is a monotonous pattern, and there is a problem that the blinding effect that makes the unevenness inconspicuous cannot be sufficiently exhibited.

  The present invention has been devised in view of the above problems, and has as its main object to provide a pneumatic tire capable of exhibiting an excellent blinding effect on the irregularities appearing on the surface of the sidewall portion. .

Plurality invention, the surface of the sidewall portion, a pneumatic tire decorative pattern is formed, in a front view of the sidewall portion, wherein the decorative pattern is that possess vital inclined radial component tire The linear patterns are arranged in the tire circumferential direction, and each linear pattern is continuous between the end portions on both sides in the tire radial direction and between the end side portions, and with respect to the tire radial direction. A central portion having an inclination angle larger than that of the end portion, the lengths L2 in the tire radial direction of the end portions on both sides are formed to be the same, and the center portion is oriented in a direction perpendicular to the longitudinal direction. The first unit pattern has protrusions that are locally protruded to one side of the tire and have a length smaller than a length L1 in the tire radial direction of the central portion, and the protrusions are arranged adjacent to each other. 3D visual effects Look including a three-dimensional pattern to the position in the tire radial direction of each convex section is characterized by gradually different in the linear pattern adjacent.

  In the pneumatic tire according to the present invention, in the front view, the linear pattern is inclined in a first direction, and the three-dimensional pattern is opposite to the first direction in the tire radial direction. It is desirable to incline in the second direction.

  In the pneumatic tire according to the present invention, the decorative pattern preferably includes a plurality of the first unit patterns in the tire circumferential direction.

In the pneumatic tire according to the present invention, the decorative pattern includes a second unit pattern in which a plurality of linear patterns having the same shape as the linear pattern but not having the convex portions are arranged in the tire circumferential direction. It is desirable that In the pneumatic tire according to the present invention, the number of linear patterns included in one second unit pattern is smaller than the number of linear patterns included in one first unit pattern. Is desirable.

  The decorative pattern of the pneumatic tire of the present invention includes a first unit pattern in which a plurality of linear patterns having components in the tire radial direction are arranged in the tire circumferential direction in a front view of the sidewall portion. Such a 1st unit pattern exhibits the blinding effect which makes the unevenness | corrugation which appears on the surface of a sidewall part inconspicuous by the arrangement | sequence of the tire circumferential direction of a linear pattern.

  Each linear pattern of the first unit pattern has a convex portion that locally projects to one side in a direction orthogonal to the longitudinal direction. And the three-dimensional pattern which has a three-dimensional visual effect is comprised by arrange | positioning the said convex part adjacent to each other in a 1st unit pattern. That is, the three-dimensional pattern provides a new pattern that emerges in a convex or concave shape in the first unit pattern, and as a result, the unevenness generated in the sidewall portion is made less noticeable.

It is the elements on larger scale of the side wall part of the pneumatic tire of this embodiment. It is AA sectional drawing of FIG. It is the elements on larger scale of a decoration pattern. It is the elements on larger scale of the 1st unit pattern. (A) is a partially enlarged view of a linear pattern showing a rectangular convex portion, (B) is a partially enlarged view of a linear pattern showing a trapezoidal convex portion, and (C) is an arc-shaped convex portion. It is the elements on larger scale of the linear pattern which shows. It is BB sectional drawing of FIG. (A) is the elements on larger scale of the side wall part which shows the linear pattern of another aspect, (B) is the elements on larger scale of the side wall part which shows the solid pattern of another aspect. (A) is a front view of the decorative pattern provided on the tire of Comparative Example 1, and (B) is a front view of the decorative pattern provided on the tire of Comparative Example 2.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a partial front view of a sidewall portion 2 of a pneumatic tire (hereinafter may be simply referred to as “tire”) 1 of the present embodiment. FIG. 2 is a tire meridian cross section including the tire rotation axis, and shows the AA cross section of FIG. 1.

  As shown in FIGS. 1 and 2, the tire 1 includes, for example, a carcass 5 and sidewall rubber 2 </ b> G disposed on the outer side of the carcass 5 in the tire axial direction. A surface 2S of the sidewall portion 2 is formed of a sidewall rubber 2G.

  A decorative pattern 3 is formed on the surface 2S of the sidewall portion 2 of the tire 1 so as to make the unevenness such as bulge and dent generated on the surface 2S of the sidewall portion 2 inconspicuous.

  The decorative pattern 3 of the present embodiment extends in a belt shape along the tire circumferential direction. The “strip shape” includes both a continuous ring shape in the tire circumferential direction and an arc shape that forms a part in the tire circumferential direction. The decorative pattern 3 of the present embodiment is continuous in an annular shape in the tire circumferential direction.

  The decorative pattern 3 is a pattern formed on the sidewall rubber 2G by, for example, vulcanization molding or cutting. The decorative pattern 3 of the present embodiment is formed when the tire 1 is vulcanized from the viewpoint of durability and productivity.

  On the inner side, the outer side, or both sides of the decorative pattern 3 in the tire radial direction, for example, ribs 4 extending along the tire circumferential direction are formed. The rib 4 of the present embodiment includes a rib 4A on the outer side in the tire radial direction of the decorative pattern 3 and an inner rib 4B. Each rib 4A, 4B protrudes outward in the tire axial direction. Such ribs 4A and 4B are useful for suppressing the occurrence of cracks and the like starting from both sides of the decorative pattern 3 in the tire radial direction.

  FIG. 3 shows a partially enlarged view of the decorative pattern 3 of FIG. In FIG. 3, the first unit pattern 6 is lightly colored for easy understanding. As shown in FIG. 3, the decorative pattern 3 of the present embodiment includes a first unit pattern 6. In a preferred embodiment, a plurality of first unit patterns 6 are arranged in a row in the tire circumferential direction. Furthermore, in a preferable aspect, the decorative pattern 3 includes the second unit pattern 7, and the first unit pattern 6 and the second unit pattern 7 are alternately arranged in the tire circumferential direction.

  FIG. 4 shows a partially enlarged view of one of the first unit patterns 6 shown in FIG. As shown in FIG. 4, the first unit pattern 6 includes a plurality of linear patterns 8 arranged in the tire circumferential direction. The first unit pattern 6 of the present embodiment is configured with 12 linear patterns 8 as one set, but this number is arbitrarily determined. As shown in FIG. 2, each linear pattern 8 is formed of, for example, a protruding object protruding outward in the tire axial direction, and this is also called a ridge. The linear pattern 8 is formed by, for example, a mold groove for vulcanizing the tire 1.

  Each linear pattern 8 has a component (length) in the tire radial direction. As long as it has a component in the tire radial direction, the linear pattern 8 includes all forms, and the shape is not particularly limited. The linear pattern 8 of this embodiment is mainly configured using linear elements. Moreover, although the linear pattern 8 of the present embodiment is inclined in the first direction (upward to the right) in FIG. 4, it may be along the tire radial direction.

  Such a first unit pattern 6 has a plurality of linear patterns 8 arranged at a relatively small pitch so that the surface 2S of the sidewall portion 2 is finely uneven, and the sidewall portion 2 is reflected by light reflecting action or the like. Makes the physical irregularities invisible inconspicuous (blind effect). The first unit pattern 6 of the present embodiment gives an impression of a streak pattern inclined in the first direction (upward to the right) as a whole by the arrangement of the linear patterns 8 with respect to what is seen.

  The plurality of linear patterns 8 belonging to the first unit pattern 6 include convex portions 9 that project locally. Each protrusion 9 protrudes on one side in a direction orthogonal to the longitudinal direction of each linear pattern 8. The convex part 9 of this embodiment protrudes on the right side of each linear pattern 8. However, the convex portion 9 may protrude to the left side of the linear pattern 8. Moreover, although the protrusion shape of the convex part 9 is not specifically limited, In a preferable aspect, it forms in V shape. As other shapes of the convex portion 9, a rectangular shape, a trapezoidal shape, an arc shape (shown in FIGS. 5A to 5C), or the like can be adopted.

  In the arrangement of the linear patterns 8 of the first unit pattern 6, the convex portions 9 are arranged adjacent to each other. In the present embodiment, the positions of the convex portions 9 in the tire radial direction are gradually different between adjacent linear patterns 8. More specifically, the position of the convex portion 9 in the tire radial direction gradually changes inward as viewed in the tire circumferential direction clockwise. Due to the arrangement of the convex portions 9, the first unit pattern 6 can include a three-dimensional pattern 10 having a three-dimensional visual effect. That is, in the first unit pattern 6, a pattern having a three-dimensional effect such as a mountain or a valley inclined as if the line connecting the vertices 9a of the convex portion 9 is a ridgeline and is inclined in the second direction (downward to the right). It can be raised.

  The three-dimensional pattern 10 as described above gives the user an impression that the surface 2S of the sidewall portion 2 has a more complicated uneven shape. Therefore, irregularities such as bulges and dents formed on the surface 2S of the sidewall portion 2 are further less visible and an excellent blinding effect can be exhibited. In particular, as in the present embodiment, when the three-dimensional pattern 10 is inclined in the second direction opposite to the linear pattern 8 inclined in the first direction, the above effect is further enhanced. In order to exhibit the above-described action more effectively, the three-dimensional pattern 10 is preferably inclined at an angle α in the range of 20 to 40 degrees, for example, with respect to the tire radial direction.

  Furthermore, since the first unit pattern 6 of the present embodiment is formed by a linear pattern 8 made of ridges, air between the surface 2S of the sidewall portion 2 and the mold is formed during vulcanization molding. The air is effectively exhausted through the groove. Therefore, the occurrence of unevenness appearing on the surface 2S of the sidewall portion 2 can be suppressed.

  As a preferable aspect, the linear pattern 8 of the present embodiment includes end portions 8a and 8a on both sides in the tire radial direction, and a central portion 8b continuous between the end portions 8a. The inclination angle β of the central portion 8b with respect to the tire radial direction is, for example, larger than the inclination angle γ of the end side portion 8a with respect to the tire radial direction. In the present embodiment, the convex portion 9 is formed in the central portion 8 b having the highest visibility of the linear pattern 8.

  In order to increase the blinding effect by making the light reflection direction different between the end portion 8a and the central portion 8b, the difference between the inclination angle γ of the end portion 8a and the inclination angle β of the central portion 8b is 15 degrees or more. It is desirable to be in the range. From the same viewpoint, the length L1 of the central portion 8b in the tire radial direction is desirably in the range of 33% to 50% of the length L of the linear pattern 8 in the tire radial direction. In a more preferred aspect, the length L2 of each end side portion 8a in the tire radial direction is formed identical to each other.

  Returning to FIG. 3, similarly to the first unit pattern 6, the second unit pattern 7 of the present embodiment includes a plurality of linear patterns 15 arranged in the tire circumferential direction. The linear pattern 15 has the same shape as the linear pattern 8 of the first unit pattern 6, but is different in that the convex part 9 is not provided. Since the first unit pattern 6 and the second unit pattern 7 are alternately arranged in the tire circumferential direction, the pattern of the sidewall portion 2 is further increased by comparing the first unit pattern 6 and the second unit pattern 7. The shape can be diversified or complicated, and the blinding effect can be further enhanced.

  The second unit pattern 7 is preferably formed of at least three linear patterns 15 in order to exhibit the above-described action more effectively. On the other hand, in the decorative pattern 3, if the distance between the three-dimensional patterns 10 of the first unit patterns 6 adjacent in the tire circumferential direction becomes too large, the blinding effect by the three-dimensional pattern 10 may not be sufficiently exhibited. From such a viewpoint, it is preferable that the number of linear patterns 15 included in one second unit pattern 7 is smaller than the number of linear patterns 8 included in one first unit pattern 6.

  FIG. 6 shows a cross-sectional view perpendicular to the longitudinal direction of each of the linear patterns 8 and 15. As shown in FIG. 6, the linear patterns 8 and 15 of the present embodiment are formed as convex ridges as described above.

  Although the height h of the linear patterns 8 and 15 is not specifically limited, For example, it is the range of 0.1-1.0 mm. When the height h is less than 0.1 mm, it is difficult to visually recognize the linear patterns 8 and 15 on the surface 2S of the sidewall portion 2, and the blinding effect that makes the unevenness inconspicuous may be reduced. On the contrary, when the height h is larger than 1.0 mm, the durability of the linear patterns 8 and 15 is lowered, and there is a possibility that cracks may be generated starting from the linear patterns 8 and 15.

  The width W perpendicular to the longitudinal direction of the linear patterns 8 and 15 is not particularly limited, but is preferably in the range of 0.4 to 2.0 mm, for example. When the width W is less than 0.4 mm, it is difficult to form the decorative pattern 3 and the productivity may be reduced. Conversely, if the width W exceeds 2.0 mm, the blinding effect may be reduced.

  The interval P between the adjacent linear patterns 8 and 15 is not particularly limited, but is preferably in the range of 0.4 to 2.0 mm, for example. When the distance P is larger than 2.0 mm, the linear patterns 8 and 15 and the contours of the projections and depressions are difficult to overlap, and the blinding effect that makes the projections and depressions inconspicuous may not be sufficiently exhibited. On the other hand, when the interval P is less than 0.4 mm, the interval between the adjacent linear patterns 8 and 15 is small, and in the decorative pattern 3, the adjacent linear patterns 8 and 15 are visually recognized as the same, and have different heights. There is a possibility that it will not be visually recognized as a ridge having a.

  FIG. 7A shows a partially enlarged view of the sidewall portion 2 showing the linear pattern 8 of another aspect. Although the linear pattern 8 of the above-described embodiment is mainly configured using linear elements, as shown in FIG. 7A, the linear pattern 8 is configured using, for example, curved elements. May be. In this embodiment, the end portions 8a and 8a and the central portion 8b of the linear pattern 8 are connected in a smooth arc shape. The linear pattern 8 configured using such arc-shaped elements can further enhance the blinding effect, for example, when the contour overlaps the contour of the unevenness generated on the surface 2S of the sidewall portion 2. .

  FIG. 7B shows a partially enlarged view of the sidewall portion 2 showing the three-dimensional pattern 10 of another aspect. The three-dimensional pattern 10 of the above-described embodiment is a pattern having a three-dimensional effect such as a straight mountain or valley. However, as shown in FIG. 7B, the three-dimensional pattern 10 is, for example, an arc-shaped mountain. Or the pattern which has a three-dimensional effect like a valley may be sufficient. Such an arc-shaped three-dimensional pattern 10 can further enhance the blinding effect, for example, because its contour is more easily overlapped with the contour of the unevenness generated on the surface 2S of the sidewall portion 2.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited to these embodiment, It can deform | transform and implement in a various aspect.

Based on the specifications in Table 1, a pneumatic tire having a decorative pattern was prototyped and its performance was tested. On the sidewall portion of each pneumatic tire, a concave portion and a convex portion of about 0.5 mm were intentionally formed at the time of vulcanization molding.
The common specifications are as follows.

Tire size: 195 / 65R15
Height of linear pattern (projection) h: 0.5 mm
Width W of linear pattern (projection): 0.8mm
The interval P between adjacent linear patterns (projections): 1.0 mm
Each test method is as follows.

<Sensitivity quality>
The decorative pattern formed on the sidewall portion of each test tire was confirmed with the naked eye, and the visual performance was evaluated by a five-point method based on the aesthetic sense of the tester. The evaluation shows that the larger the score, the better the visual performance and the better the sensitivity quality.

<Recessed blindfold performance>
In the side wall portion of each test tire, the concave portion was confirmed with the naked eye, and the distinguishability of the concave portion was evaluated by a five-point method based on the tester's sensuality. The evaluation shows that the larger the score, the more difficult it is to identify the recesses and the better the blinding performance.

<Convex blinding performance>
At the sidewall portion of each test tire, the convex portion was confirmed with the naked eye, and the distinguishability of the convex portion was evaluated by a five-point method based on the tester's sense. The evaluation shows that the larger the score is, the more difficult it is to identify the convex portion and the better the blinding performance.

  As a result of the test, it was confirmed that the tires of the examples were excellent in blindfold performance and sensitivity quality.

DESCRIPTION OF SYMBOLS 1 Pneumatic tire 2 Side wall part 2S Surface 3 Decoration pattern 6 1st unit pattern 8 Linear pattern 9 Convex part 10 Three-dimensional pattern

Claims (5)

A pneumatic tire having a decorative pattern formed on the surface of the sidewall portion,
In the front view of the sidewall portion,
The decorative pattern may include a first unit pattern by arranging a plurality of linear patterns which possess vital inclined tire radial component in the tire circumferential direction,
Each of the linear patterns includes end portions on both sides in the tire radial direction, and a central portion that is continuous between the end portions and has a larger inclination angle with respect to the tire radial direction than the end portions.
The length L2 in the tire radial direction of the end portions on both sides is formed identical to each other,
The central portion locally protrudes to one side in a direction orthogonal to the longitudinal direction and has a convex portion having a length smaller than the length L1 of the central portion in the tire radial direction ,
Wherein the first unit pattern is seen containing a three-dimensional pattern having a three-dimensional visual effects that are arranged in the convex portions adjacent to each other,
The position of each said convex part in the tire radial direction is gradually different by the said linear pattern which adjoins, The pneumatic tire characterized by the above-mentioned . In the front view, the linear pattern is inclined in a first direction,
The pneumatic tire according to claim 1, wherein the three-dimensional pattern is inclined in a second direction opposite to the tire radial direction from the first direction. The pneumatic tire according to claim 1, wherein the decorative pattern includes a plurality of the first unit patterns in a tire circumferential direction. The said decoration pattern contains the 2nd unit pattern which arranged the some linear pattern which has the same shape as the said linear pattern, but does not have the said convex part in the tire circumferential direction. Pneumatic tire described in 2. The pneumatic tire according to claim 4, wherein the number of the linear patterns included in one of the second unit patterns is smaller than the number of the linear patterns included in one of the first unit patterns.

Images