JP2600172Y2 - Winter tires - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a winter tire having a columnar synthetic resin spike pin.

[0002]

2. Description of the Related Art Conventional tires have significantly reduced dynamic characteristics on winter roads, particularly on frozen roads. This is because the coefficient of friction (μ) between the rubber surface of the tire and ice is extremely small. In order to improve this, spike pins for tires have been developed, and those using metal spike pins have been used in snowy areas. As a result, it is possible to run sufficiently stable even on frozen road surfaces,
It was to ensure safety. Studless tires have also been used as a replacement, but they are inferior to metal spike pins, but have been able to achieve moderate running on moderately frozen roads without damaging the road. Further, there has been a type in which a portion that is in contact with a road surface is made of resin and provided with a spike pin made of a synthetic resin so as not to cause damage to the road surface (see Japanese Patent Application Laid-Open No. 1-257607).

[0003]

As described above, there are winter tires including metal spike pins, synthetic resin spike pins, and studless tires, but the metal spike pins damage the road surface. However, there are problems such as the occurrence of dust pollution, and some regions have been banned. Further, in a studless tire, since a frictional force against ice is generated by a drainage effect of the ice surface, if the amount of water generated from the ice is large, a braking effect is not so much obtained. Furthermore, if the spike pins made of synthetic resin are used for a long time, they will be worn and the edges will be dull, so that a sufficient edge effect will not be obtained, and ice shavings will adhere around the pins, There were problems such as slipping because they did not peel off, and that the pins themselves were also plastically deformed in the case of soft spikes. The present invention has been made in order to solve the above-described problem, and has a synthetic resin spike pin that has durability and an excellent spike effect as compared with a conventional synthetic resin spike pin. It aims to provide winter tires.

[0004]

In order to achieve the above object, in the winter tire of the present invention, a plurality of independent blocks circumferentially divided by grooves on a cylindrical tread engaging with the tread surface are provided. Arranged, in the tire provided with a pillar-shaped synthetic resin spike pin in the specific block, the spike pin is divided at least in the front and rear grooves in the rotation direction of the tire, substantially from the pedestal recessed further from the radial outer surface of the block. What is provided is that it protrudes to the level of the radially outer surface of the block.

[0005]

In the winter tire provided with the synthetic resin spike pin configured as described above, the spike pin is divided by grooves at least in the front and rear directions in the tire rotation direction, and is further depressed from the radially outer surface of the block. By projecting from the pedestal substantially to the level of the radially outer surface of the block, wear during running is small, and at the time of braking, the spike pin projects due to deformation of the tread rubber, and the edge effect by the edge of the spike pin, that is, The spike effect is fully exhibited. On the other hand, if the spike pins protrude from the outer surface in the radial direction of the block from the beginning, the spike pins are mainly worn, so that the spike pins themselves are liable to be deformed or damaged, and are also liable to come off. In addition, if the spike pins are divided by grooves in the direction of rotation of the tire as in the prior art, and the spike pins are buried directly in the block itself without providing a pedestal that is further depressed from the radial surface of the block, the rotation of the tire Since there is little deformation in the front-rear direction due to the engagement of the tread rubber including the inner block with the road surface, the spike effect by the spike pins does not occur.

[0006]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 (a) and 1 (b) are partial structural views showing main parts of an embodiment of the present invention, and FIGS. 2 (a) and 2 (b) are tread patterns and main structural views of the embodiment of the present invention, respectively. In FIG. 1, reference numeral 1 denotes a part of a cylindrical tread which engages with a road surface. In the tread 1, a plurality of independent blocks 2 defined by grooves (no reference numeral) are circumferentially arranged in a plurality of rows. FIG. 1A shows an arbitrary independent block.
As shown in the figure, a columnar synthetic resin spike pin 3 is buried in the center of a pedestal 4 which is lower than the radially outer surface of the center block 2, and the pedestal 4 is provided with a groove 5 around it. Have been. The groove 5 may be present in the front-rear direction, and is preferably provided in the front-rear, left-right direction. The distal end surface 6 of the synthetic resin spike pin 3 projects from the surface of the pedestal 4 to a position substantially at the same level as the distal end surface 7 which is the radially outer surface of the block 2. Here, the position of substantially the same level means a protrusion of about 1.5 mm from the front end surface 7 of the block 2 shown in FIG. 2B.

In FIG. 1 (a), a to f indicate locations where dimensions and the like are specified in an actual design so that the winter tire in the embodiment exhibits an expected effect. As described above, in the present embodiment, the height of the pedestal is about 1.5 mm, the height b of the pedestal is 20 to 50% of the block height d, and the projection amount c of the synthetic resin spike pin on the pedestal is equal to the height e of the spike pin. When (1/10) · e <c <(3/4) · e, preferably (1/5) · e <c <(1/2) · e (Reason: When e is too small, traveling Sometimes the pin comes off, and if e is too large, a sufficient frictional force on ice cannot be obtained.) D indicates the block height, which is determined by the design of each tire. f indicates the height from the pedestal upper surface to the block upper surface, and this height indicates the height from the block upper surface, and this height is 5 of the block height.
0 to 80%, which is a portion serving as a friction allowance as a so-called spike tire.

As the synthetic resin material for the spike pins, ultrahigh molecular weight polyethylene having an average molecular weight of 1,000,000 or more, nylon 66, polyacetate, MC nylon, fluororesin, polyurethane resin, and the like can be considered. Any conventionally used material, such as a blend of styrene and ultra high molecular weight polyethylene, may be used. Needless to say, the spike pin can be manufactured by a conventionally known compression molding, injection molding, transfer molding or the like. Further, the mechanical strength is about the same as that of a conventional cemented carbide, and Rockwell hardness (R scale: ASTM73)
5) It is only necessary to be about 40, and if it is 85 or more, the example in which the spike pin 3 is driven into the block 2 of the block pattern as shown in FIG. Thirteen winter radial tires were mounted with a predetermined number of 64 tires having the dimensions shown in [Table A], mounted on an actual vehicle, and after running 300 km, evaluated, and the results were shown. The synthetic resin material of the spike pin used at that time is ultra-high molecular weight polyethylene (trade name, HIZEX Million 340M, Mitsui Petrochemical Industry Co., Ltd.)
Manufactured) and having a Rockwell hardness of 40.

I. Size

[Table A]

II. result Note: Friction on ice is 100 for studless tires (Bridgestone, Bridgestone; size 185 / 70R-13)
The braking distance at the time of the lock brake from 20 km / h on the ice plate at the time of the evaluation was evaluated, and was calculated by the following equation. _{Blissac braking distance Friction on ice = × 100} The braking distance of the tire of each example From the above results, even if the winter tire of the present invention provided with the spike pin was the same as that provided with the same synthetic resin spike pin, the pin did not come off during running. It was also confirmed that the frictional force on ice was much better than the conventional one shown in Comparative Example. This means that the same effect can be obtained as long as the spike pin has the above-described configuration, even though the material of the spike pin is slightly different.

[0011]

[Effects of the Invention] As described in detail above, the present invention is constructed, so that there is no generation of dust noise unlike a conventional spike pin, and there is no pin detachment even after long use. In addition, it produces a remarkable frictional force on ice by exerting a sufficient edge effect compared to studless tires, so it produces an excellent spike effect and can run on frozen roads stably, In this respect, the present invention has an effect such as being equivalent to a conventional metal spike pin.

[Brief description of the drawings]

FIG. 1A is a side view showing a main structure of an embodiment of the present invention. (B) is a plan view showing a main structure of the embodiment of the present invention.

FIG. 2A is a diagram showing a tread pattern according to an example of the present invention. (B) is an enlarged view of a main part structure of the embodiment of the present invention.

[Explanation of symbols]

 Reference Signs List 1 tread rubber 2 block 3 synthetic resin spike pin 4 pedestal 5 groove 6 tip surface of synthetic resin spike pin 7 tip surface of block

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) B60C 11/16 B60C 11/11 B60C 5/00

Claims (1)

(57) [Scope of request for utility model registration] In a tire, a plurality of independent blocks whose periphery is divided by grooves are arranged in a circumferential direction in a cylindrical tread engaging with a road surface and a plurality of rows are arranged in a circumferential direction, and the specific block has a columnar synthetic resin spike pin. The spike pin is at least divided into grooves at the front and rear in the rotation direction of the tire, and protrudes from a pedestal further depressed from the radial outer surface of the block to substantially the level of the radial outer surface of the block. For tires.