JPH07257111A - Pneumatic tire and vulcanizing forming mold for manufacturing it - Google Patents

Abstract

PURPOSE:To make new points (micro foams, foreign matter, etc.) appear on a tire ground contact surface for improved tractive force and braking force on the snowy or icy road at the time of initial driving by forming fine roughness on a surface where a unused tire is mounted for conscious roughing, and giving earlier wear to the tire only at the time of the initial driving. CONSTITUTION:Roughness 3a distributed roughly uniformly is formed over the whole periphery of a tire ground contact surface 1. In the roughness, there are various shapes such as 3a, 3b, 3c, 3d, 3e, 3f. In any shape, the distribution of single shape or mixed distribution of plural shapes of more than two types is available. Even at the time of shorter driving distance than a conventional type of tire, it is possible to achieve more tractive force and braking force on the snowy or icy road. A rising curve of tractive force and braking force shows gentle rising somewhat, however, it is an early rising curve, which has a merit of tractive force and braking force starting to increase early.

Description

Detailed Description of the Invention

[0001]

[Industrial application] The present invention increases the traction force and braking force of winter and all-season tires at the beginning of running, and improves the performance of the tire on snow and on ice (driving, braking, cornering, climbing power, etc.). The present invention relates to a fine shape of a tire ground contact surface for compression, a tire vulcanizing mold for molding the shape, and a method for manufacturing the mold.

[0002]

2. Description of the Related Art In winter and all-season tires that require traction and braking, micro bubbles can be placed in the rubber at the ground contact portion, and the performance can be achieved by mixing foreign substances other than rubber. Many innovations have been made in the past. But,
The ground contact surface roughness of a non-running tire is normally maintained on a smooth surface of 30 μm or less, and the devising point of bending angle does not appear on the surface. Therefore, the traction force on the snow and ice in the early stages of running,
There is almost no technology to improve the braking force.

[0003] The only thing to mention is that the number of vent spews in the tire ground contact surface is reduced by devising the vulcanization of the tire.
Or, it is only the technology to make it zero. However, even with this method, the tire ground contact surface roughness when not running is still 30 μm or less on a smooth surface, and the performance of the initial running due to the inside of the rubber at breaks (micro bubbles, mixing of foreign substances, etc.) We cannot show improvement.

[0004]

The smooth surface of 30 μm of the conventional tire runs on the pavement surface, and it takes a dozen kilometers to reach the point where the inside of the rubber appears, but on snow or ice. When traveling, it is necessary to travel several times that distance. Therefore, the object of the present invention is to ensure the superiority of the tire on snow and ice,
The point is to make the ingenuity of the conventional technology (micro bubbles, foreign substances, etc.) appear on the tire ground contact surface as soon as the running distance is short.

[0005]

[Means for Solving the Problems] In order to bring out the ingenuity of the prior art at an early stage, it is necessary to quickly wear the rubber surface of the unrun tire. The mileage and the amount of rubber wear on the tire contact surface are almost directly proportional to each other.Therefore, if you make the contact surface of a non-running tire fine with irregularities and intentionally make it rough, the wear will progress early only at the beginning of running In the tire according to the present invention, ingenuity points appear earlier than in the conventional tire.

[0006]

In the tire 4 according to the present invention and the conventional tire, the ingenuity of the conventional technology (micro bubbles, foreign substances, etc.) does not appear on the surface in the unrunning line 4, so the performance on snow and ice is There is not much difference. However, in the tire tread wear line 5 after traveling 5 a kilometers, in the tire according to the present invention, bubbles and foreign substances do not appear, whereas in the tire according to the present invention, some of them appear and the traction force and braking force are improved. start. Further, the performance of the conventional tire and the tire of the present invention reach the same level only after reaching the wear line 6 after traveling for 5 b kilometers. Therefore, the tire of the present invention cannot exhibit its ability as a studless tire until the vehicle travels for 5 b kilometers, whereas the tire of the present invention begins to exert its ability early.

[0007]

EXAMPLE An unevenness 3a is formed which is substantially evenly distributed over the entire circumference of the tire ground contact surface 1. The uneven shape is 3a, 3b,
Various shapes such as 3c, 3d, 3e, 3f are conceivable, but any shape may be a single shape distribution or a mixed distribution of two or more kinds of plural shapes.

[0008]

The first effect of the present invention is the merit 7 that the traction 11 on snow and ice and the braking force 11 increase at a time when the traveling distance is shorter than that of the conventional tire. The second effect is that the rising curve of the traction force and the braking force increase is different from the rising curve 9 of the conventional tire, and the rising curve becomes a curve 10 that rises earlier, even though the rising curve is somewhat gentle. Is the merit 8 that starts to increase faster.

[Brief description of drawings]

FIG. 1 is a perspective view of a tire cut in a sectional direction.

FIG. 2 is a tire cross-sectional view showing that fine irregularities 3a are distributed on a tire ground contact surface 1.

FIG. 3 is an enlarged schematic view of an example of fine unevenness.

FIG. 4 is an enlarged schematic view showing a mixed distribution state of micro bubbles or foreign substances near the tire ground contact surface, showing the tire tread rubber of the tire (a) according to the present invention and the conventional tire (b) at the same traveling distance. Shows wear line.

FIG. 5 is a curve graph schematically showing comparison levels of traction force and braking force on snow and ice with respect to a mileage between a conventional tire and a tire according to the present invention.

[Explanation of symbols]

 1 Tire Contact Surfaces 3a, 3b, 3c, 3d, 3e, 3f Fine Concavo-convex Shapes 4, 5, 6 Wear Level Lines 5a, 5b Mileage 7,8 Merits According to the Present Invention 9,10 Traction Force, Braking Force Increase Rise Curve 11 Traction Force ,Braking force

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Claims (5)

[Claims] 1. A winter or all-season tire having fine irregularities on the ground contact surface of a non-running pneumatic tire, a die for producing the tire, and a method for producing the die. 2. The tire according to claim 1, wherein the height of the unevenness is 1 mm or less at the maximum and 30 μm or more at the minimum, and a vulcanization mold for producing the tire. 3. The tire according to claim 1, wherein the number of the irregularities is 25 or more per square centimeter, and the vulcanization mold for producing the tire. 4. The projections and depressions in the unevenness are chevron (3a, 3b), chamfered (3c, 3d), trapezoidal (3).
e, 3f) The tire according to claim 1, wherein the tire has a single shape or a mixed arrangement and distribution of a plurality of shapes.
Vulcanization mold for manufacturing it. 5. The method for processing fine irregularities of the mold transferred to the rubber surface during tire vulcanization includes a method of preliminarily processing irregularities in a casting mold such as gypsum, sand, ceramics, die-casting mold, or the like. The mold for tire production according to claim 1, wherein after the casting, the metal surface of the mold is processed by any method such as machining, electrolytic corrosion (EDM) processing, etching processing, and shot blasting.