JP2013023110A - Tire stud and studded tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire stud for improving the braking performance and driveability of a tire on an ice road surface and traction performance on a snow road surface, and a studded tire having the tire stud.SOLUTION: The tire stud includes a columnar body which has a recess formed in one axial-direction end surface, and a pin which is arranged in the recess and partially protruded from the end surface of the body. The pin comprises a first part and two second parts extended from the first part so as to form a bent part with the first part, in the radial cross-section of the pin, and is opened in one direction. This stud has a proper cross-sectional shape.

Description

  The present invention relates to a tire spike used in a spike tire and a spike tire formed by driving a tire spike into a spike driving hole formed on a tread surface.

  Conventionally, as a winter tire with improved driving performance on icy roads (ice roads) and snowy roads, metal spikes (sometimes called "studs") are formed in a plurality of holes formed on the tread surface. Spike tires that are driven in are known.

  Here, as spikes used for spike tires, generally, a cylindrical body having a small hole formed on one end face (sometimes referred to as “shank”) and a hard body press-fitted into a small hole in the body. A spike is used that includes a pin and a flange for preventing the pin from being provided integrally with the body on the other end face side of the body (see, for example, Patent Document 1).

The spike is driven into a hole formed in the tread portion tread so that the flange to one end surface of the body is embedded in the tread portion and the pin protrudes from the tire surface.
In general, the pin is formed using an ultra-hard metal such as tungsten steel, and the body and the flange are formed using a metal such as an aluminum alloy or steel.

By the way, in the spike tire in which the spike is driven into a plurality of holes formed in the tread portion tread, the spike that has been driven scratches ice and snow and increases the frictional resistance of the tire.
Specifically, in the spike tire, as shown in FIG. 1, first, the pin 12 of the spike 11 embedded in the tread portion 10 comes into contact with the road surface 13 (ice road or snowy road). Next, when the body 15 partially protruding from the hole 14 due to the contact between the pin 12 and the road surface 13 comes into contact with the road surface 13, the spike 11 scratches ice and snow, and the running performance is improved.

International Publication No. 2008/130275

  In recent years, in order to improve the on-ice performance and on-snow performance of spike tires as described above, the need to ensure the safety of vehicle travel has increased. Need to increase.

  An object of the present invention is to provide a tire spike and a spike tire having the tire spike that can improve the braking performance and driving performance of the tire on an icy road surface and the traction performance on a snowy road surface. is there.

The inventors have intensively studied to solve the above problems.
As a result, new knowledge about the cross-sectional shape of the spike was obtained, which can enhance both the edge effect on the ice road surface and the effect of scraping snow on the snow road surface.

This invention is made | formed based on said knowledge, The summary structure is as follows.
(1) A tire spike comprising a columnar body having a recess formed on one end surface in the axial direction, and a pin disposed in the recess and partially protruding from the end surface of the body,
The pin is composed of a first portion and two second portions extending from the first portion so as to form a bent portion with the first portion in a radial section of the pin. A spike for a tire, characterized by having a shape opened to the top.

  (2) The tire spike according to (1), wherein an angle θ formed by the bent portion is 90 to 135 °.

  (3) The tire according to (1) or (2) above, wherein the one direction is the designated tire rotation direction in a state where the one direction is driven into a hole formed in a tread surface of a spike tire having a designated rotation direction. Spikes.

(4) When the tire spike is driven into the hole, the length of the pin projected in the tire circumferential direction is L1, and the length of the pin projected in the tire width direction is L2. L1 / L2 is
0.7 ≦ L1 / L2 ≦ 1.5
The tire spike according to (3), wherein

(5) A spike tire having a designated rotational direction,
The tire spike according to any one of the above (1) to (4) is driven into a hole formed in a tread surface so that the one direction is the designated tire rotation direction. Spike tire.

  According to the present invention, it is possible to provide a tire spike and a spike tire having the tire spike, which can improve the braking performance and driving performance of the tire on an icy road surface and the traction performance on a snowy road surface. it can.

It is a figure for demonstrating a mode that the conventional spike tire scratches a road surface. It is a figure which shows the spike for tires concerning one Embodiment of this invention. It is a schematic perspective view which shows a pin. It is a figure which shows the shape of a pin typically. It is an expanded view which shows the tread surface of the spike tire concerning one Embodiment of this invention. (A) It is a schematic perspective view which shows the shape of the conventional pin. (B) It is a schematic perspective view which shows the shape of the pin concerning a comparative example. It is a figure for demonstrating the dimension of a pin.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 2 is a diagram showing a tire spike (hereinafter simply referred to as a spike) according to an embodiment of the present invention.
As shown in FIG. 2, a spike 1 according to the present invention is formed on a substantially cylindrical body 2 and one end face 2a in the direction of the axis of the body 2 (a central axis C extending in the longitudinal direction of the body 2). A pin 3 disposed in the concave portion and a flange 4 for preventing slipping provided integrally with the body 2 are provided on the other end surface side in the axial direction of the body 2.

FIG. 3 is a schematic perspective view showing a pin. FIG. 4 is a plan view schematically showing the shape of the pin.
As shown in FIGS. 3 and 4, the pin 3 includes a first portion 3 a and a first portion 3 a in a radial section of the pin 3 (a section perpendicular to the axial direction D of the pin 3). The first portion 3a and the two second portions 3b and 3c extending so as to form the bent portion 5 have a shape opened in one direction.
Here, the axial direction of the pin 3 is the same direction as the direction of the axis C of the body when it is disposed on the body.
In the illustrated example, the second portions 3b and 3c respectively extend from both ends of the first portion 3a in the normal direction (the same direction) of the first portion 3a, and the bent portion 5 is 90 °. The angle is made.
Hereinafter, as shown in FIG. 5, the spike in which the pin having the above shape is disposed in the concave portion is formed in the hole 7 formed in the tread surface 6 of the spike tire in which the rotation direction is specified. A description will be given of the function and effect of driving in such a manner.

First, in the above case, the pin 3 has a shape in which the first portion 3a extends in the tire width direction, the two second portions 3b and 3c extend in the tire circumferential direction, and opens toward the tire rotation direction. It becomes.
At this time, according to the present invention, on the ice surface, first, the first portion 3a of the pin 3 secures the edge component in the width direction on the kicking side, so that the ice braking performance and the ice driving performance are improved. .
Furthermore, in the radial cross section, the pin has a shape opened to the stepping side by the first portion 3a on the kicking side extending in the tire width direction and the two second portions 3b and 3c extending in the tire circumferential direction. It has become.
For this reason, it is closed on the kicking side, so it can harden snow and increase the shear force of the snow column, and because it has an open shape only on the stepping side, the tire rotates while gripping snow reliably. Increases the effect of scraping snow in the direction. Therefore, the snow traction performance is improved.
In addition, since the two second portions 3b and 3c extend in the tire circumferential direction, an edge component during turning of the vehicle can be secured, so that turning performance is improved on an icy and snowy road surface.
Furthermore, since the bent portion 4 is provided, the braking performance particularly on the icy road surface is improved by the piercing effect of the bent angle, as compared with the curved shape without the bent angle.
In addition, the pins can be reduced in weight as compared with the conventional pins as shown in FIG.

Here, as shown in FIG. 7, the angle θ formed by the bent portion 5 is preferably 90 to 135 °.
Because, by setting it to 90 ° or more, it is possible to obtain the effect that ice and snow that is securely grasped at the opening when stepped on will be scraped out at the time of kicking out, and continue to ensure the merit of driving performance on ice and snow. is there. On the other hand, by setting the angle to 135 ° or less, it is possible to prevent the snow grasped at the time of stepping from escaping as much as possible, so that the driving performance on ice and snow can be improved.

Here, as shown in FIG. 7, when the length of the pin projected in the tire circumferential direction is L1, and the length projected in the tire width direction is L2, the ratio L1 / L2 is:
0.7 ≦ L1 / L2 ≦ 1.5
It is preferable to satisfy.
This is because by setting the ratio L1 / L2 to be 0.7 or more, the edge component in the circumferential direction can be secured, and the above-described snow traction performance and vehicle turning performance can be further improved.
On the other hand, by setting the ratio L1 / L2 to 1.5 or less, it is possible to secure the edge component in the width direction and further improve the above-described braking performance on ice and driving performance on ice.
In addition, about the said circumferential direction projection length, it shall be the length which does not include the overlap part at the time of projecting.

In order to confirm the effect of the present invention, a spike according to the inventive example and the comparative example was experimentally manufactured.
Moreover, the spike concerning a prior art example was prepared.
Each of these spikes was driven into a hole in the tread portion tread surface of a tire having a tire size of 195 / 65R15, the internal pressure was set to 230 kPa, and the following tests for evaluating tire performance were performed.

<Ice braking performance>
The braking distance when the vehicle was suddenly braked from a speed of 20 km / h on an ice surface was evaluated.
This is expressed as a relative value when the braking distance of the conventional example is 100, and the smaller the index, the shorter the braking distance and the better the performance.
<Drive performance on ice>
On the road surface on ice, the time until the vehicle started from a stationary state and reached a speed of 10 km / h was evaluated.
This is expressed as a relative value when the time in the conventional example is set to 100, and the smaller the index, the shorter the time and the better the braking distance.
<Driving on snow>
On the road surface on the snow, the time until the vehicle started from a stationary state and reached a speed of 20 km / h was evaluated.
The acceleration time in the conventional example is 100, and the smaller the value, the shorter the time and the better the performance.
The specifications and evaluation results of each tire are shown in Table 1 below.

  As shown in Table 1, it can be seen that the tire according to the invention example is superior in braking performance on ice, driving performance on ice, and traction performance on snow than the tires according to the conventional example and the comparative example.

1 Spike 2 Body (shank)
2a End surface 3 Pin 3a First portion 3b, 3c Second portion 4 Flange 5 Bending portion 6 Tread portion tread surface 7 Hole 10 Tread portion 11 Spike 12 Pin 13 Road surface 14 Hole 15 Body (shank)

Claims (5)

A spike for a tire comprising a columnar body having a recess formed on one end surface in the axial direction, and a pin disposed in the recess and partially protruding from the end surface of the body,
The pin is composed of a first portion and two second portions extending from the first portion so as to form a bent portion with the first portion in a radial section of the pin. A spike for a tire, characterized by having a shape opened to the top.   The tire spike according to claim 1, wherein an angle θ formed by the bent portion is 90 to 135 °.   The tire spike according to claim 1 or 2, wherein the one direction is the designated tire rotation direction in a state of being driven into a hole formed in a tread surface of the spike tire for which a rotation direction is designated. When the length of the pin projected in the tire circumferential direction is L1 and the length of the pin projected in the tire width direction is L2 in a state where the tire spike is driven into the hole, the ratio L1 / L2 Is
0.7 ≦ L1 / L2 ≦ 1.5
The tire spike according to claim 3, wherein: A spike tire with a specified direction of rotation,
A spike tire, wherein the tire spike according to any one of claims 1 to 4 is driven into a hole formed in a tread surface so that the one direction is the designated tire rotation direction.

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