JPS599923Y2 - spike tires - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a spiked tire that prevents slipping on frozen road surfaces, and more particularly to a spiked tire that allows studs embedded in the tire contact surface to be buried within the tire when not needed.

In conventional spiked tires, when not in use or when not in contact with the ground, the studs 2 are connected to the tire 1 as shown in Figure 1.
During use or when touching the ground, as shown in Figure 2, the tire 1 is deformed due to the weight load and is exposed to the surface of the tire 1, causing it to sink into the road surface. It's starting to bite into 3.

And this is the same regardless of the condition of the road surface, that is, even if it is a general road without snow, ice, etc.

For this reason, on general roads, the studs damage the road surface, and as the tires constantly engage and disengage at high speed, they cause noise, are uncomfortable to ride, and further reduce fuel efficiency.

Furthermore, since the studs touch the ground even when driving on public roads, their lifespan is short and there are problems such as the studs coming off in a short period of time.

The present invention was developed to solve these conventional problems, and its purpose is to provide a spiked tire that can reduce noise on general roads, improve ride comfort, improve fuel efficiency, and extend life. There is something to do.

This invention focuses on the fact that the road surface temperature is significantly different between ordinary roads and snowy or icy roads.The studs shrink at room temperature and are buried inside the tire, and at low temperatures they expand and are exposed on the tire surface and touch the ground. The studs are made of a shape-memory metal that prevents the studs from coming into contact with the ground on public roads.

By the way, shape memory metal is a general term for metals that when the material is deformed and then heated, the material returns to the shape before deformation, that is, it remembers its original shape.TiNi, C
u3Al, CuAINi, AuCd, Fe3P
This is a phenomenon that appears in alloys such as t, InTI, NiAl, CuZn, and others.

The cause of such shape memory is now generally understood as the phenomenon of martensitic transformation.

This is because martensite continuously expands as the temperature decreases, and conversely contracts as the temperature increases.
These are caused by a transformation called thermoelastic martensitic transformation that can be reversibly transferred, and martensitic I is caused by elongated twin deformation caused by temperature drop or stress.
・ is absorbed into the matrix and decomposed due to reverse transformation due to its good compatibility with the matrix when heated.

In other words, the cause of the deformation at low temperatures is eliminated by heating, so the original shape is restored, and this is thought to be the cause of the memorability.

Therefore, it can basically be understood by the above-mentioned mechanism, and by searching for the conditions and heat treatment conditions that cause thermoelastic martensitic transformation due to twin deformation, it is possible to discover the combination of various metals.

The present invention will be explained below based on an embodiment shown in FIG.

FIG. 3 shows a stud 12 that is buried in the ground contact surface of a tire (not shown). The stud 12 has a shape in which the center of the cylindrical portion bulges outward as shown in FIG. 3 at room temperature of about 10°C or above, and as shown in FIG. 4 at about 0°C to 4°C or below. It is shaped so that it can be deformed into an extended state.

Therefore, due to the reversible shape memory effect, when the road surface is cold, the studs 12 expand as shown in FIG. 4, and when the road surface is at room temperature, the studs 12 shrink by the dimension S as shown in FIG. It looks like this.

In the above structure, when the studs 12 formed of shape memory metal are buried in the tire, the studs 12 will be expands as shown in Figure 4, and the tire (
(not shown), and in the case of a normal temperature road (10°C) such as a general road, the stud 12 is reduced by the dimension S as shown in Fig. 3, and the load on the vehicle is applied. Even if a tire (not shown) is deformed, it will not be exposed from the tire contact surface.

As explained above, according to this embodiment, the studs do not touch the ground when driving on general roads, so there is no damage to the road surface, generation of noise, deterioration of riding comfort, and deterioration of fuel efficiency.
Further, it is possible to achieve a longer life.

Furthermore, since the stud is shaped like a cylinder, a reversible shape memory effect appears prominently.

Note that as the shape memory metal for the stud 12, TiNi alloy is most preferable from the viewpoint of corrosion resistance and strength.

Further, in the above embodiment, the entire cylindrical stud 12 is made of shape memory metal, but only a part of it, for example, only the cylindrical part, may be made of shape memory metal, or the stud 12 may be made of shape memory metal instead of being cylindrical. It can also be eaten as fruit.

The present invention has been explained above based on the preferred embodiments. According to the present invention, it is possible to reduce noise on ordinary roads, improve ride comfort, improve fuel efficiency, prevent road damage, and extend life. And on icy roads, the spike effect can be activated automatically.

[Brief explanation of drawings]

Figures 1 and 2 are cross-sectional views taken along the plane passing through the wheel rotation axis, showing the effect of studs on spiked tires, Figure 3 is a front view of the stud according to the present invention at room temperature, and Figure 4 is a front view showing the state under the same low temperature. 1... Tire, 2, 12... Stud, S... Deformation dimension.

Claims (1)

[Claims for Utility Model Registration] 1. In a spiked tire in which studs are buried in the tire contact surface to prevent slipping on frozen roads, etc., at least a portion of the studs shrinks and is buried in the tire at room temperature. , and is characterized by being made of a shape-memory metal that expands when the temperature is low and is exposed on the tire surface and makes contact with the ground. 2. The spike tire according to claim 1 of the utility model registration claim, in which the studs are shaped like a tube.