JPH0332484B2 - - Google Patents

Description

[Detailed Description of the Invention] (a) Object of the Invention [Field of Industrial Application] This invention relates to a spiked tire used when wheels run on icy and snowy roads.

[Prior Art] In order to prevent tires from slipping when a vehicle drives on an icy road such as an icy road, it has been conventional to use spiked tires that have a plurality of spikes protruding from the tire tread. Are known.

The conventional spike tire is Snow Tire 101.
As shown in FIG. 4, spikes 102 are driven in,
It has a structure that protrudes approximately 1.5 to 2.0 mm from the tire surface. spike 102 shank 10
103 made of cemented carbide or the like is usually attached to the tip of 4 for friction resistance.

Conventional spiked tires have this structure, so on roads without ice or snow, the spikes 1
02 scrapes the road surface and scatters it into the atmosphere as dust, causing pollution problems. As a countermeasure, we are currently reducing the protrusion of the spikes to 1.0 to 1.5 mm.
or the number of spikes.
Efforts have been made to reduce the number of tires from 154 tires per tire to 122 tires per tire, but this does not essentially solve the pollution problem, and on the other hand, the performance of tires on icy and snowy roads has deteriorated. Spiked tires are considered to be a safety issue as they may cause a decrease in the road surface and are considered to be a safety issue.For these reasons, spiked tires are designed to maintain tire performance on icy and snowy surfaces without scraping the road surface. development is desired.

For this purpose, technology is being considered to move the spikes of spiked tires in and out depending on the road surface conditions when it is frozen or not.In this case, the temperature of the road surface can be detected to drive the spikes in and out. However, estimating the state of road slippage from the road surface temperature is an extremely indirect detection method.

[Problems to be solved by the invention] This invention has been made in view of the above circumstances, and directly corresponds to the frozen and non-frozen conditions of the road surface. It is possible to use the difference in the coefficient of friction as is to change the length of the spikes protruding from the tire surface, to move them below the tire surface, or to hide the spikes, thereby preventing them from scraping the road surface. The object of the present invention is to provide a spiked tire that is particularly simple in structure, quick to operate, and reliable, and which does not reduce the performance of the tire on icy and snowy surfaces. .

(B) Structure of the Invention [Means for Solving the Problem] Corresponding to this object, the spiked tire of the present invention is a spiked tire in which a spike having a shank for holding a chip is attached to a snow tire, The spike includes a columnar shank and a chip attached to the axial tip of the shank, and is elastically displaceable when a lateral displacement force component is applied when an axial load is applied to the shank. and a shoe that is supported around the tip and located outside of the tip in the axial direction, and the friction coefficient of the shoe with respect to the running road surface when frozen is greater than the friction coefficient with respect to the running road surface when not frozen. It is also characterized by being small.

Hereinafter, details of the present invention will be explained with reference to the drawings showing one embodiment.

In Fig. 1, 1 is a spiked tire;
A spiked tire 1 includes spikes 2. The spike 2 has a columnar shank 3, and the shank 3
A tip 4 is fixed to the distal end of the shank 3, and a flange 5 is formed at the base end of the shank 3. The shank 3 is buried in the tire 6 with its tip exposed outward, and the flange 5
prevents the shank from slipping out. At the distal end of the shank 3, a shoe 7 is arranged substantially flush with the distal end surface of the tip 4. The shoe 7 is made of rubber or plastic, and as will be described later, the selection of its coefficient of friction is particularly important.
The shoe 7 is elastically supported by a leaf spring 8. The leaf spring 8 is made of steel and is provided at an angle with respect to the axis of the shank 3. Therefore, when the axial load of the shank 3 acts on the leaf spring 8, a displacement force component is generated in a direction perpendicular to the axis of the shank.
The shoe 7 and the leaf spring 8 detect slippage between the running road surface and the tire tread surface or the spike tip by utilizing the fact that the coefficient of friction between the running road surface and the tire tread surface or the spike tip is different when the running road surface is frozen and when the running road surface is not frozen. , and, correspondingly, the tip 4 is made to protrude or exposed, or the tip of the tip 4 is made to retreat or be hidden.

[Function] Spike tires constructed in this way take advantage of the fact that the coefficient of friction between the running road surface and the tire road surface or tips is different between frozen and non-frozen conditions. On non-frozen roads such as dry roads, the tips of the spikes are moved back or hidden to reduce contact between the spike tips and the road surface.
Reduce wear and tear on the road surface. Its specific action is as follows.

First, when the spiked tire 1 is used to drive on a concrete road surface free of ice and snow, the chips 4 do not come into contact with the road surface, but only the shoes 7 come into contact with the road surface. The shoe 7 receives a load from the road surface in the axial direction of the shank 3, and a component force is generated in the leaf spring 8 in a direction parallel to the road surface. Therefore, the shoe 7 does not cause any axial displacement of the shank 3, the load from the road surface is borne by the leaf spring 8, the shoe 7 is in contact with the road surface, and the tip 4 is The chips 4 do not come into contact with the road surface, so the chips 4 do not scrape the road surface.

Next, when tire 1 runs on an icy road surface,
Since the coefficient of friction between the shoe 7 and the ice and snow is small, the shoe 7 causes sideways skidding due to the component force in the direction parallel to the road surface generated in the leaf spring 8. As a result, the shoe 7 is moved to the spiked tire as shown by the chain line in Figure 1. The tip 4 retreats inward in the radial direction of the tip 1, and the tip 4 relatively protrudes outward, bites into the ice and snow on the road surface, and functions as a spike.

As shown in FIG. 3, if the leaf spring 8 is provided with a hem portion 11 along the shank 3, it is easy to maintain the desired posture of the shank 7 even when a lateral load is applied to the spike 2. It is.

(c) Effects of the invention As is clear from the above explanation, according to the present invention, whether the road surface is frozen or not, it is possible to
By directly utilizing the difference in the coefficient of friction between frozen and non-frozen road surfaces, it is possible to change the protrusion length of the spikes from the tire surface, move them below the tire surface, or hide the spike tips. As a result, it is possible to obtain a spike tire with a simple structure that does not scrape the road surface and does not reduce the performance of the tire on icy and snowy surfaces. It is particularly important to note that although it has traditionally been considered to control the entry and exit of spikes according to temperature, estimating the road surface condition from the temperature condition is an indirect method of detecting the road surface condition. However, in the present invention, since the slippage of the road surface is directly used as a signal, it is possible to respond extremely well to the condition of the road surface.

[Brief explanation of the drawing]

FIG. 1 is a cross-sectional explanatory diagram showing a spiked tire according to an embodiment of the present invention, FIG. 2 is a plan view explanatory diagram of the spike, and FIG. 3 is a cross-sectional diagram showing a spiked tire according to another embodiment of the present invention. Figure, and the fourth
The figure is an explanatory longitudinal cross-sectional view showing a conventional spiked tire. 1...spiked tires, 2...spikes, 3...
...Shank, 4...Chip, 5...Flange, 6
... Tire, 7... Shoe, 8... Leaf spring.

Claims (1)

[Claims] 1. A spike tire comprising a snow tire with a spike having a shank for holding a chip, the spike having a columnar shank, a chip attached to the axial tip of the shank, and an axial load on the shank. a shoe that is elastically supported so as to be displaceable when a lateral displacement force component is applied thereto, and is located outside the tip in the axial direction around the tip. A spike tire characterized in that a coefficient of friction of the shoe with respect to a running road surface when frozen is smaller than a coefficient of friction with respect to a running road surface when not frozen.