JPS6259110A - Spike tire - Google Patents

Abstract

PURPOSE:To prevent the breakage of a road surface when the road surface is not in frozen state, by forming a layer made of the polymer or the rubber composition having a glass transition temperature in a specific range at the basic edge part of a spike and covering at least the side surface of the layer by the rubber elastic body having a compression permanent strain in a specific value. CONSTITUTION:A spike tire is formed by burying a number of shanks (spike) 1 having a flange 2 at the basic edge part into a tread part 6, and a tip 3 is installed at the top edge part of the shank 1. In this case, a rubber elastic body 4 in container form into which polymer or a rubber composition 5 is charged is installed on the basic edge side of the shank 1, namely on the edge surface on the side where the flange 2 is installed. The polymer or the rubber composition 5 having a glass transition temperature of -20-0 deg.C is used, and the rubber elastic body 4 having a compression permanent strain of 20% or less is used. Therefore, when a road surface is not in frozen state, the shank 1 can prevented effectively.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a spike tire, and particularly relates to a spike tire that can be used to improve the appearance of a tire when running. be.

[Prior Art] Tires with spikes are widely used for driving on snowy or frozen roads.

Conventionally known spikes of this type include a flange at the proximal end of the shank, and a flange at the distal end.
There is one that has a fixed cemented carbide tip.

However, with such conventional spikes, the chips always protrude from the tire tread surface regardless of whether the road surface is frozen, so the protruding chips can cause significant damage to the road surface, especially when the road surface is not frozen. At the same time, there is a problem in that the protruding chips are severely abraded by the road surface. On the other hand, such a phenomenon has attracted particular attention in recent years. This caused noise and dust pollution while driving, and also led to poor fuel efficiency.

Therefore, in order to solve this problem, research has been carried out to improve spikes.
110303, JP-A-150101, JP-A-57
-134303, JP-A-48-93004, JP-A-53
-140703, JP-A-52-18602, JP-A-50
-83902, JP-A-52-66204, etc.), the protrusion amount is 2j1 depending on the volumetric expansion coefficient of the liquid due to external force, temperature change, etc.
! ! What I do (Unexamined Japanese Patent Publication No. 51-126603. Unexamined Japanese Patent Publication No. 4
7-17103, etc.), a rubber material whose elastic modulus changes with temperature changes is attached to the flange end, and the amount by which the spike is pushed into the tire is adjusted by external force (JP-A-59
-199307, JP-A-59-199308), etc. have been proposed.

[Problems to be solved by the invention] However, most of the above conventional methods are
It had defects in terms of performance and lacked practicality.

In addition, JP-A-59-199307, JP-A-59-199
The spike tire disclosed in No. 308, in which a rubber material whose elastic modulus changes with temperature changes is attached to the flange end and is configured to adjust the amount that the spike is pushed into the tire by external force, utilizes the glass transition temperature of the rubber. Although they are somewhat effective at the beginning of use, after a certain period of use, the rubber material creeps, and as a result, the spikes remain embedded in the tire, causing them to no longer function as spikes. However, there was a problem that the product would disappear, and it lacked durability and practicality.

[Means for Solving the Problems] The spiked tire of the present invention includes a layer of a polymer or rubber composition having a glass transition temperature in the range of 120 to 0° C. on the proximal end surface of the spike. , at least the side surfaces of the layer are covered with a rubber-like elastic material having a compression set of 20% or less.

In the present invention, the polymer or rubber composition having a glass transition temperature in the range of 120 to θ°C is a copolymer of styrene and a conjugated diene such as butadiene or isoprene, which has a relatively high styrene content. Copolymers of acrylonitrile and conjugated dienes such as butadiene or isoprene with a relatively high content of acrylonitrile, polymers such as norbornene rubber, or combinations of these with zinc oxide, stearic acid, carbon black, etc. Vulcanized rubber compositions and vulcanized rubber compositions are suitable. These may be used alone or in combination of two or more.

The glass transition temperature of these polymers and rubber compositions is
In particular, the temperature is preferably -15 to -5°C.

Further, the above polymer and rubber composition preferably have a JIS hardness of 80 or more in an atmosphere at a temperature of 0°C or lower, and a JIS hardness of 70 or less in an atmosphere at a temperature of 30°C or higher. The rubber composition preferably has a relatively low viscosity.

In addition, in the present invention, as the rubber-like elastic body, any rubber-like elastic body commonly called an elastomer, such as vulcanized rubber and thermoplastic elastomer, can be used. The compression set of an elastic body is 2
0% or less, preferably 10% or less, more preferably 5
% or less.

Further, at a temperature lower than the glass transition temperature of the polymer or rubber composition to be encapsulated, the rigidity of the rubber-like elastic body is not particularly restricted, but in order to reliably prevent creep of the polymer or rubber composition, The rubber-like elastic body preferably has a stiffness higher than that of the polymer or rubber composition at a temperature equal to or higher than the glass transition temperature of the rubber composition, and moreover, the stiffness of the rubber-like elastic body is preferably higher than that of the polymer or the rubber composition, and the stiffness of the rubber-like elastic body is higher than that of the tire tread layer in which the spikes are embedded. By using such a combination of stiffnesses, which are preferably lower than the stiffness of rubber, it becomes possible to more reliably prevent creep of the polymer or rubber composition.

In addition, in the present invention, at least the side surface of the layer of polybu or rubber composition having a glass transition temperature in the range of 120 to θ°C may be coated with a rubber-like elastic body having a compression set of 20% or less, The bottom surface or even the top surface of the layer of the polymer or rubber composition may be coated with the rubbery elastic body, and the polymer or rubber composition and the rubbery elastic body may be laminated.

The method for producing a layer of the polymer or rubber composition with at least the side surface covered with the rubbery elastic material is as follows: (1) forming a container or shell-like body with the rubbery elastic material, and disposing the polymer or rubber composition inside the container or shell-like body; Enclose things.

(2) The polymer or rubber composition is made into a small plate-like piece, and the rubber-like elastic body is also made into a small plate-like piece, and both plate-like pieces are alternately overlapped and bonded.

Various methods can be adopted, such as.

In the present invention, the layer of the polymer or rubber composition and the rubber-like elastic body covering it may be provided by adhering to each spike, or may be provided on the tread rubber layer of the tire on the proximal end side of the spike. It may also be embedded in a position where it contacts the end surface.

Further, a layer of rubber constituting the tire body may be interposed between the layer of the polymer or rubber composition and the rubber-like elastic body covering the layer and the proximal end surface of the spike.

[Function] In the spiked tire of the present invention, when the road surface temperature, or in some cases the atmospheric temperature, is higher than 0°C, the polymer and rubber composition having a glass transition temperature in the range of 120 to θ°C can significantly hardness decreases. For this reason, the layer of the polymer or rubber composition provided on the proximal end surface of the spike significantly reduces the pressing force applied to the spike in the direction of protrusion of the tire surface, and the spike is prevented from coming into contact with the road surface. It retreats into the tire due to the pressing force in the backward direction.

On the other hand, when the road surface temperature or atmospheric temperature falls below the melting point of water, the hardness of the polymer and rubber composition increases,
In particular, when the temperature is below these glass transition temperatures, the polymer and rubber composition have extremely high hardness. For this reason.

Overcoming the pressure in the backward direction due to contact with the road surface,
Spikes protrude from the tire surface. This makes it possible to fully exert its effect on frozen road surfaces.

Furthermore, in the spiked tire of the present invention, the polymer and rubber composition having a glass transition temperature in the range of -20 to 0°C are encapsulated or composited into a rubber-like elastic body having a compression set of 20% or less. It compensates for the creep properties of the polymer and rubber composition, and as a result, it becomes possible to obtain a spiked tire with high durability.

[Example] Examples of the present invention will be described in detail below with reference to the drawings.

1 to 4 are cross-sectional views showing the spike installation part of an embodiment of the spiked tire of the present invention, and in the figures, 1
2 indicates the shank, 2 indicates the flange provided at the base end of shank l, 3 indicates the tip provided at the tip of shank I, and 4A-D indicate a rubber-like elastic body with a compression set of 20% or less. , 5 has a glass transition temperature in the range of -20 to θ℃, and a JIS hardness of 7 in an atmosphere at a temperature of 30℃ or higher.
JIS hardness in a temperature atmosphere of 0 or less and 0°C or less.

Polymer or rubber composition with a degree of 80 or more, and 6 indicates the tread portion of the tire.

The spiked tire according to the embodiment shown in FIG. 1 is provided with a container-shaped rubber-like elastic body 4A in which a polymer or rubber composition 5 is encapsulated on the base end side of the spike, that is, on the end face portion on the flange 2 side. It is.

The spiked tire according to the embodiment of FIG. 2 has a protrusion 4 in the center.
A rubber-like elastic body 4B having a container shape is provided. In FIG. 2, by providing the protrusion 4a,
It becomes possible to more reliably supplement the creep resistance of the polymer or rubber composition 5.

In the embodiment shown in FIG. 2, the protrusion 4a may be columnar or wall-shaped.

The spiked tire shown in FIG.
C encapsulated with polymer or rubber composition 5,
It is provided on the end face portion of the spike on the flange 2 side.

The spiked tire shown in FIG. 4 has layers of rubber-like elastic body 4D and layers of polymer or rubber composition 5 alternately laminated in a direction perpendicular to the end surface of the spike on the flange 2 side.

[Effects of the Invention] The spiked tire of the present invention controls the protrusion of the spikes from the tire surface by utilizing changes in the hardness of the polymer or rubber composition depending on the environmental temperature. Furthermore, by coating at least the side surfaces of the layer of the polymer or rubber composition with a rubbery elastic material, the layer is reinforced and the creep properties of the layer are enhanced.

The spiked tire of the present invention can maintain the spikes in a protruding state only when the road surface is frozen, so it effectively prevents damage to the road surface and chips without impairing the original function of the spikes, and also reduces noise during driving. , it is possible to improve fuel efficiency. Furthermore, due to the reinforcing effect of the rubber-like elastic body with a compression set of 20% or less, it is said to be extremely durable and can withstand long-term use.

[Brief explanation of drawings]

1 to 4 are sectional views each showing an embodiment of a spike tire according to the present invention. l...shank, 2...flange, 3...
... Chip, 4A, 4B, 4C14D ... Rubber-like elastic body with compression set of 20% or less. 5... Polymer or rubber composition having a glass transition temperature of 120 to θ°C. Agent Patent Attorney Shigeno
Rigid tree 1 Figure 3 Figure 2 Figure 4

Claims (2)

[Claims] (1) In a spiked tire in which spikes are provided in the tire tread, a layer of a polymer or rubber composition having a glass transition temperature in the range of -20 to 0°C is provided, and at least the side surface of the layer is made of a compression set. A spiked tire characterized by being coated with 20% or less of a rubber-like elastic material. (2) At a temperature equal to or higher than the glass transition temperature of the polymer or rubber composition, the stiffness of the rubber-like elastic body is higher than the stiffness of the polymer or rubber composition and lower than the stiffness of the tire tread rubber. A spiked tire according to claim 1, characterized in that: