RU2807196C1 - Stud and pneumatic tire equipped with stud - Google Patents

Abstract

FIELD: automotive industry.

SUBSTANCE: stud (P) is made with a recessed base part (10), which is configured to be recessed into a section of the tire tread, and an apical end section (20), which is located at the end part of the recessed base part (10) and comes into contact with the road surface. The apical end part (20) has an outer contour (21) made in a ring shape, an inner contour (22) surrounded by an outer contour (21), and a groove part (23) located between the outer contour (21) and the inner contour (22). In the tire (T), the stud (P) is located on the tread area (31).

EFFECT: improved performance on ice due to enhanced edge effect.

7 cl, 9 dwg, 1 tbl

Description

Field of technology

The present invention relates to a stud and a tire equipped with a stud, and in particular to a stud capable of improving performance on ice by enhancing the edge effect, as well as to a tire equipped with a stud.

State of the art

Among the pneumatic tires having improved performance on icy and snowy road surfaces, studded tires (tires with studs) are known, in which the studded studs are recessed into the tread area (see, for example, publications JP 5702817 B, JP 5997518 B and JP 6111010 B ). Each stud stud has a recessed base portion configured to be recessed into a portion of the tire tread, and an apical end portion that is located at the end end of the recessed base portion and comes into contact with the road surface. When the studded tire is driven, the edge of the apical end portion of the studded stud comes into contact with the icy road surface and creates an edge effect, thereby exhibiting excellent performance on ice.

However, since in the known design of a stud stud and a tire equipped with a stud stud, the individual studs do not provide sufficient edge effect, the performance on ice is not necessarily satisfactory. Thus, there is a need to further improve on-ice performance.

Technical problem

An object of the present invention is to provide a stud that improves performance on ice by enhancing the edge effect, and a tire provided with such a stud.

Solution

The stud stud according to an embodiment of the present invention to achieve the above object is a stud stud having a recessed base portion configured to be recessed into a portion of the tire tread, and an apical end portion that is located at an end end of the recessed base portion and comes into contact with a road surface, the apical end portion including an outer contour formed in an annular shape, an inner contour surrounded by an outer contour, and a groove portion located between the outer contour and the inner contour.

The tire according to an embodiment of the present invention to achieve the above object is characterized in that the above stud is located on the tread portion.

Advantages of the invention

In one embodiment of the present invention, since the apical end portion of the tenon stud includes an outer contour formed in a ring shape, an inner contour surrounded by an outer contour, and a groove portion located therebetween, the outer contour and the inner contour form edges that can significantly Strengthen the edge effect of the stud and effectively improve the tire's performance on ice. In particular, if the apical end portion of the tenon stud is composed of an annular outer contour and an inner contour surrounded by an outer contour, it is possible to ensure sufficient strength of each of the outer contour and the inner contour.

In one embodiment of the present invention, the groove portion preferably remains continuous in an annular shape around the inner contour. In this case, the edge effect can be enhanced to significantly improve performance on ice. Further, it is preferable that the apical end portion of the tenon stud includes at least one connecting portion that connects the outer contour and the inner contour with each other, and that the total length of the inner perimeter of the groove portion is at least 50% of the length of the outer perimeter of the inner contour. In this case, it is possible to increase the strength of the tenon stud.

The inner contour preferably has a groove portion on its inner side extending along its outer perimeter. In this case, since the extent of the edges increases even more, the performance on ice can be significantly improved.

It is preferable that the shape of the inner peripheral zone of the outer contour and the shape of the outer peripheral zone of the inner contour are different from each other. In this case, it is possible to improve the snow removal characteristics of the apical end portion of the stud and further improve the performance on ice by increasing the length of the edges. The shape of the inner peripheral zone of the outer contour and the shape of the outer peripheral zone of the inner contour may be similar. In this case, one can expect the formation of a sufficient edge effect.

The interval Ly between the outer contour and the inner contour, measured in a direction orthogonal to the central axis of the tenon stud, is preferably in the range of 10% to 35% of the size Lx of the outer contour, measured in a direction orthogonal to the central axis of the tenon stud. As a result, the strength of the cleat stud can be largely ensured and deterioration in snow removal performance and performance can be avoided.

Further, it is preferable that the inner contour includes a main inner contour portion located on the outermost inner side, and the size Lz of the main inner contour portion measured in a direction orthogonal to the central axis of the tenon stud is preferably in the range of 10% to 60 % of the Lx size of the outer contour, measured in the direction orthogonal to the central axis of the tenon stud. As a result, the strength of the cleat stud can be largely ensured and deterioration in snow removal performance and performance can be avoided.

The tire according to an embodiment of the present invention is preferably a pneumatic tire, but may be a non-pneumatic tire. In the case of a pneumatic tire, the interior may be filled with air, an inert gas such as nitrogen, or other gas.

Brief description of drawings

Fig. 1 is a perspective view illustrating a tenon stud according to an embodiment of the present invention;

Fig. 2 is a plan view of the tenon stud shown in FIG. 1;

Fig. 3 is a cross-sectional view of the tenon stud shown in FIG. 1;

Fig. 4 is a cross-sectional view along line IV-IV shown in FIG. 2;

Fig. 5 is a plan view illustrating a modified example of a tenon stud;

Fig. 6 is a plan view illustrating another modified example of a tenon stud;

Fig. 7 is a plan view illustrating another modified example of a tenon stud;

Fig. 8 is a plan view illustrating another modified example of a tenon stud; And

Fig. 9 is a meridional cross-sectional view illustrating an example of a pneumatic tire according to one embodiment of the present invention.

Description of Embodiments of the Invention

The configurations of embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In FIG. 1-4 show a tenon stud in accordance with an embodiment of the present invention.

As shown in FIG. 1-4, the stud stud P of the present embodiment includes a recessed base portion 10 configured to be recessed into a portion of a tire tread, and an apical end portion 20 that is located at an end end of the recessed base portion 10 and comes into contact with the road surface. The recessed base part 10 consists of a body section 11, which has a cylindrical shape, a neck 12, which has a cylindrical shape and is connected to the body section 11, and also has a smaller diameter than the body section 11, and a lower part 13, which has a cylindrical shape and connected to the neck 12, which has a larger diameter than the neck 12. The metal material that makes up the apical end portion 20 has a higher hardness than the metal material that makes up the recessed base portion 10, and the recessed base portion 10 and the apical end portion 20 form a single unit.

In the tenon stud P, the apical end portion 20 includes an outer contour 21 formed in an annular shape, an inner contour 22 having a cylindrical shape and surrounded by an outer contour 21, and a groove portion 23 located between the outer contour 21 and the inner contour 22. Thus , at the end of the outer perimeter and at the end of the inner perimeter of the contact surface with the ground of the outer contour 21, edges are formed, and an edge is also formed at the end of the outer perimeter of the contact surface with the ground of the inner contour 22.

As described above, since the apical end portion 20 of the tenon stud P includes an outer contour 21 formed in a ring shape, an inner contour 22 surrounded by an outer contour 21, and a groove portion 23 disposed therebetween, the outer contour 21 and the inner contour 22 form edges, which can greatly enhance the edge effect of the stud P and effectively improve the tire's performance on ice. Particularly, if the apical end portion of the tenon stud P includes an annular outer contour 21 and an inner contour 22 surrounded by the outer contour 21, it is possible to ensure that each of the outer contour 21 and the inner contour 22 is sufficiently strong.

As shown in FIG. 2, in the tenon stud P, it is preferable that the groove portion 23 has an annular shape around the inner contour 22. In this case, the extent of the edges at the inner perimeter end of the inner contour 21 and at the outer perimeter end of the inner contour 22 can be maximized to enhance the edge effect and substantially improve characteristics on ice.

In FIG. Figure 5 shows a modified example of a tenon stud. In FIG. 5, the apical end portion 20 of the tenon stud P is formed with a plurality of connecting portions 24 that connect the outer contour 21 and the inner contour 22 to each other. The connecting portions 24 are arranged to extend radially with respect to the central axis of the tenon stud P. Moreover, if the connecting portions 24 are provided between the outer contour 21 and the inner contour 22, the total length of the inner perimeter of the groove portion 23 is preferably 50% or more of the length of the outer the perimeter of the inner contour 22. For example, as shown in FIG. 5, if the length values of the inner perimeter of the four divided parts of the groove portion 23 separated by the connecting portions 24 are designated as L1, L2, L3 and L4, their sum is designated as La (La=L1+L2+L3+L4), and the length of the outer perimeter the inner contour 22 (the length of the outer perimeter assuming that there are no connecting portions 24) is designated Lb, preferably La ≧ 0.5 × Lb. In this case, the strength of the tenon stud P can be increased. In this case, if the total length of the inner perimeter of the groove portion 23 is less than 50% of the outer perimeter length of the inner contour 22, the effect of improving the performance on ice is reduced due to the reduction in the extent of the edges.

In FIG. 6-8 shows a modified example of a tenon stud. As shown in FIG. 6, the inner contour 22 has an inner side groove portion 22C extending annularly along its outer peripheral edge, wherein the inner contour 22 is divided into an inner contour main portion 22A located on the outermost inner side and an outer inner loop edge portion 22B, located on the outer perimeter. By dividing the inner contour 22 into the inner contour body portion side 22A and the inner contour outer edge portion 22B as described above, the extent of the edges is further increased so that on-ice performance can be substantially improved.

In FIG. 7 and 8, the shape of the inner peripheral zone of the outer contour 21 and the shape of the outer peripheral zone of the inner contour 22 are different from each other. As shown in FIG. 7, the inner peripheral zone of the outer contour 21 is circular in shape, and the outer peripheral zone of the inner contour 22 is square in shape. As shown in FIG. 8, the inner peripheral zone of the outer contour 21 is circular in shape, and the outer peripheral zone of the inner contour 22 is elliptical in shape. Thus, because the inner peripheral region of the outer contour 21 and the outer peripheral region of the inner contour 22 have different shapes, it becomes possible to improve the snow removal performance of the apical end portion 20 of the stud P and further improve the performance on ice by increasing the extent of the edges.

Note that the shape of the inner peripheral zone of the outer contour 21 and the shape of the outer peripheral zone of the inner contour 22 may be similar (see FIG. 2). In this case, one can expect the formation of a sufficient edge effect. There is no special limitation on the shape of the inner peripheral zone of the outer contour 21 and the shape of the outer peripheral zone of the inner contour 22, and various shapes such as circle, ellipse and polygon, including quadrangle, can be used.

As shown in FIG. 4, the interval Ly between the outer contour 21 and the inner contour 22, measured in a direction orthogonal to the central axis O of the tenon stud P, is preferably in the range of 10% to 35% of the dimension Lx of the outer contour 21, measured in a direction orthogonal to the central axis O of the tenon stud hairpin P, and more preferably in the range of 15% to 30%. As a result, the strength of the tenon stud P can be largely ensured and deterioration in snow removal performance and performance can be avoided. Here, if the Ly interval between the outer contour 21 and the inner contour 22 is too small, the snow removal performance and performance deteriorate, and if the Ly interval is too large, the strength of the stud P is reduced.

Moreover, with respect to the inner contour body 22A located on the innermost side in the inner contour 22, the size Lz of the inner contour body 22A measured in a direction orthogonal to the central axis O of the tenon stud P is preferably in the range of 10% to 60%, and more preferably in the range of 20% to 40% of the dimension Lx of the outer contour 21 measured in a direction orthogonal to the central axis O of the tenon stud P. As a result, the strength of the tenon stud P can be largely ensured and deterioration in the snow removal performance and operational characteristics. Here, if the size Lz of the inner contour main portion 22A is too small, the strength of the tenon stud P is reduced, and conversely, if it is too large, the snow removal performance and performance are deteriorated.

The dimension Lx of the outer contour 21, measured in a direction orthogonal to the central axis O of the tenon stud P, is preferably set in the range of 2 mm to 4 mm. In addition, the thickness t of the outer contour 21, measured in a direction orthogonal to the central axis O of the tenon stud P, is preferably set in the range of 0.3 mm to 0.6 mm. As a result, the strength of the tenon stud P can be largely ensured and deterioration in snow removal performance and performance can be avoided.

The dimension Lx of the outer contour 21, the interval Ly between the outer contour 21 and the inner contour 22, the dimension Lz of the inner contour body 22A, and the thickness t of the outer contour 21 are measured at random positions around the central axis O of the tenon stud P at positions where the outer contour 21 and the inner contour 22 is separated by sections of the groove 23. When the outer contour 21 or the inner contour 22 is chamfered, the size is measured assuming that there is no chamfered section.

In FIG. 9 is an example of a pneumatic tire according to an embodiment of the present invention. As shown in FIG. 5, the pneumatic tire T includes a tread portion 31 extending in a circumferential direction of the tire and having an annular shape, a pair of sidewall portions 32, 32 respectively located on either side of the tread portion 31, and a pair of bead portions 33, 33 disposed on the inner side of the sidewall portions 32 in the radial direction of the tire.

A carcass layer 4 is disposed between a pair of bead portions 33, 33. The carcass layer 34 includes a plurality of reinforcing cords extending in the radial direction of the tire and folds back around a bead core 35 located in each of the bead portions 33 between the tire inner side and the outer side. tires. At the periphery of the circumference of the bead core 35 is placed a bead filler 36 having a triangular cross-sectional shape and formed from a rubber composition.

At the same time, a plurality of breaker layers 37 are built into the outer perimeter of the carcass ply 34 of the tread portion 31. Each of the belt layers 37 includes a plurality of reinforcing cords that are inclined relative to the circumferential direction of the tire, and these reinforcing cords are arranged to cross each other between the layers. For example, in the belt layers 37, the angle of the reinforcing cords relative to the circumferential direction of the tire is set to be within a range of 10° to 40°. Steel cords are preferably used as the reinforcing cords of the breaker layers 37. To improve durability when driving at high speeds, at the outer perimeter of the belt layers 37 there is at least one layer of belt cover 38 formed by installing reinforcing cords, for example, at an angle of no more than 5° relative to the circumferential direction of the tire. Organic fiber cords, such as nylon or aramid, are preferably used as reinforcing cords for the breaker cover layer 38.

In the above pneumatic tire T, main grooves 41 extending in the circumferential direction of the tire are formed on the tread portion 31, and a plurality of tread portions 42 are formed by the main grooves 41. A plurality of mounting holes 43 for installing studs P are formed on the tread portions 42 of the tread portion 31. . The tenon pin P is located on the tread portion 31 such that the recessed base portion 10 is inserted into the mounting hole 43 and the apical end portion 20 protrudes from the tread portion 31. The inner diameter of the mounting hole 43 is slightly smaller than the outer diameter of the stud P, and the stud P installed in the mounting hole 43 is securely held with respect to the tread portion 31.

As described above, by installing studs P with a predetermined structure on the tread portion 31 of the pneumatic tire T, excellent performance on ice based on the edge effect of the studs P can be achieved.

It should be noted that the reinforcing structure of the pneumatic tire T shown in FIG. 9 is a representative example and is not limited to it. In addition, the tread pattern formed on the tread portion 31 of the pneumatic tire T is not particularly limited.

Examples

Pneumatic tires with a tire size of 205/55R16 94T were manufactured in accordance with the typical example and examples 1-4 and differ only in the installation structure of the studs placed on the tread area.

In a typical example, a tenon stud with a recessed base portion and an apical end portion was used, such an apical end portion being made in a cylindrical shape. In examples 1-4, a tenon stud with a recessed base part and an apical end section was used, in which the apical end section is made with an annular outer contour, the inner contour is surrounded by an outer contour, and a groove section is located between them. As shown in Table 1, in Examples 1 to 4, the presence or absence of a groove portion on the inner side in the inner contour, the shape of the inner peripheral zone of the outer contour, and the shape of the outer peripheral zone of the inner contour are determined.

The ice performance of these test tires was evaluated according to the following test methods, and the results are shown in Table 1.

Performance on ice

During the evaluation, each of the test tires was mounted on a wheel with a rim size of 16 × 6.5J, installed on a front-wheel drive car with an engine capacity of 1400 cc. cm and pumped up to an air pressure of 250 kPa. The distance from the braking point when moving at a speed of 20 km/h on ice to the stopping point was measured. The evaluation results were expressed using index values using the reciprocal of the measured values, with the example value set to 100. Higher index values indicate excellent on-ice performance.

Table 1

Typical example Example 1 Example 2 Example 3 Example 4 The presence or absence of a groove section on the inner side in the inner contour - Absence Absence Availability Availability Shape of the inner peripheral zone of the outer contour - Round Round Round Round Shape of the outer peripheral zone of the inner contour - Round Square Round Square Performance on ice 100 105 108 110 113

As can be seen in Examples 1 to 4 of Table 1, since the apical end portion of the tenon stud was formed with an annular outer contour, an inner contour surrounded by an outer contour, and a groove portion located between them, excellent performance on ice can be achieved by strengthening the edge spike stud effect compared to a typical example.

List of reference items

10 - recessed base part

11 - section of the body

12 - neck

13 - bottom section

20 - apical end section

21 - external contour

22 - internal circuit

22A - main part of the inner circuit

22B - outer edge portion of the inner contour

22C - groove section on the inner side

23 - groove section

24 - connecting section

31 - tread section

P - tenon stud

T - pneumatic tire

Claims (11)

1. Tenon stud containing: a recessed base portion configured to be recessed into a portion of the tire tread; And an apical end portion, which is located at the end end of the buried base portion and comes into contact with the road surface, wherein the metal material of which the apical end portion is composed has a higher hardness than the metal material of which the buried base portion is composed and the buried base the part and the apical end section form a single whole, wherein the apical end portion has an outer contour made in a ring shape, an inner contour surrounded by an outer contour, and a groove portion located between the outer contour and the inner contour, wherein the groove is made ring-shapedly continuous around the inner contour. 2. The tenon stud according to claim 1, wherein the inner contour has a groove portion on the inner side extending along its outer peripheral edge. 3. The tenon stud according to claim 1 or 2, wherein the shape of the inner peripheral zone of the outer contour and the shape of the outer peripheral zone of the inner contour are different from each other. 4. The tenon stud according to claim 1 or 2, in which the shape of the inner peripheral zone of the outer contour and the shape of the outer peripheral zone of the inner contour are similar. 5. Tenon stud according to any one of paragraphs. 1-4, in which the interval Ly between the outer contour and the inner contour, measured in the direction orthogonal to the central axis of the tenon stud, is in the range from 10% to 35% of the size Lx of the outer contour, measured in the direction orthogonal to the central axis of the tenon stud. 6. Tenon stud according to any one of paragraphs. 1-5, in which the inner contour includes a main inner contour portion located on the outermost side, and the dimension Lz of the main inner contour portion measured in a direction orthogonal to the central axis of the tenon stud is in the range of 10% to 60% of the dimension Lx outer contour measured in a direction orthogonal to the central axis of the tenon stud. 7. A tire, on the tread section of which there is a spike stud according to any one of claims. 1-6.