JP2013023195A - Tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire which has a small tire width and a large tire diameter, and which can secure performance on a wet road and a snowy and icy road, equivalent to that of a conventional general tire.SOLUTION: In the pneumatic tire 10, the tire width SW and the outside diameter OD of the tire satisfy relationships: SW≤175 mm and OD/SW≥3.6. An inclined groove 100 is elongated while being curved toward the outside of a tread width direction Dfrom a central portion in the tread width direction D. The angle α of the inclined groove 100 except the central portion with respect to the tread width direction Dis smaller than the angle α of the inclined groove 100 in the central portion with respect to the tread width direction D. A circumferential groove 200 is formed only between the inclined grooves 100.

Description

  The present invention relates to a tire in which a plurality of circumferential grooves are formed, a tire width SW and a tire outer diameter OD satisfy a relationship of SW ≦ 175 mm and OD / SW ≧ 3.6, and in particular, wet roads and ice / snow The present invention relates to a tire for ensuring performance on a road.

  2. Description of the Related Art Conventionally, various tread patterns are used for pneumatic tires (hereinafter referred to as tires) mounted on passenger cars and the like in order to improve performance on icy and snowy roads. For example, by forming a plurality of inclined grooves inclined in the tire circumferential direction in the tread central part in the tread width direction and lug grooves extending in the tread width direction between adjacent inclined grooves, the tire is formed in the tread central part. A tire provided with a zigzag land portion extending in the circumferential direction is known. Further, a zigzag sipe extending in the tread width direction is formed in the land portion (see Patent Document 1).

JP-A-8-216623 (FIG. 1)

  In recent years, reducing rolling resistance has contributed to improving fuel economy and reducing tire noise. So, especially in so-called city commuters, which are mainly used in urban areas, the tire width tends to decrease and the tire diameter increases. There is.

  In such a tire having a small tire width and a large tire diameter, it has been required to ensure performance on wet roads and icy and snowy roads equivalent to conventional general tires.

  Therefore, the present invention has been made in view of such a situation, and in a tire having a narrow tire width and a large tire diameter, performance on wet roads and snowy roads equivalent to conventional general tires is ensured. The object is to provide a tire.

A feature of the present invention is that a plurality of circumferential grooves (circumferential grooves 200) extending in the tire circumferential direction (tire circumferential direction D _C ) are formed, the tire width SW and the tire outer diameter OD are SW ≦ 175 mm, and OD /SW≧3.6 (pneumatic tire 10) satisfying the relationship, the inclined groove curves from the center in the tread width direction (tread width direction D _T ) toward the outside in the tread width direction. However, the angle (angle α) with respect to the tread width direction of the inclined groove other than the central portion is smaller than the angle with respect to the tread width direction of the inclined groove in the central portion, and the circumferential groove is inclined. The gist is that it is formed only between the grooves.

  According to the characteristics of the present invention, a tire having a narrow tire width and a large tire diameter can provide a tire that can ensure performance on a wet road and an icy / snow road equivalent to a conventional general tire.

1 is a partial plan view of a tread of a pneumatic tire 10 according to an embodiment of the present invention. 1 is a partially enlarged plan view of a tread of a pneumatic tire 10 according to an embodiment of the present invention.

  Next, an embodiment of a tire (pneumatic tire) according to the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar parts are denoted by the same or similar reference numerals. However, it should be noted that the drawings are schematic and ratios of dimensions and the like are different from actual ones.

  Accordingly, specific dimensions and the like should be determined in consideration of the following description. Moreover, the part from which the relationship and ratio of a mutual dimension differ also in between drawings may be contained.

(1) Schematic Configuration of Pneumatic Tire FIG. 1 is a partial plan development view of a tread of the pneumatic tire 10 according to the present embodiment. As shown in FIG. 1, the pneumatic tire 10 is inclined grooves 100 inclined relative to the tire circumferential direction D _C is formed with a plurality in the tire circumferential direction D _C. Further, in the pneumatic tire 10, the circumferential groove 200 extending in the tire circumferential direction D _C is formed with a plurality.

  The pneumatic tire 10 is a so-called winter tire that can withstand use during snowfall, and has a tread pattern in which the direction of rotation when mounted on an automobile is specified. The winter tire here refers to a tire including a studless tire that places importance on performance on icy and snowy roads, and an all-season tire that ensures a balanced performance on icy and non-snowy roads. The pneumatic tire 10 may be filled with an inert gas such as nitrogen gas instead of air. Moreover, in FIG. 1, the thin line part means the area | region which does not touch a road surface at the time of a regular internal pressure and a regular load.

  The pneumatic tire 10 is a tire having a small tread width and a large tire diameter in which the tire width SW and the tire outer diameter OD satisfy the relationship of SW ≦ 175 mm and OD / SW ≧ 3.6. For example, the size of the pneumatic tire 10 includes 155 / 60R20. The pneumatic tire 10 can be used for a so-called city commuter mainly used in an urban area.

  As shown in FIG. 1, the tire width SW is the width of the entire pneumatic tire 10 at the time of normal internal pressure and normal load. The tire outer diameter OD is a diameter based on the tread surface of the pneumatic tire 10 at the time of normal internal pressure and normal load.

Inclined groove 100 extends while curving toward the central portion of the tread width direction D _T in the tread width direction D _T outside, except the central portion, i.e., the tread width of the inclined grooves 100 in the tread width direction D _T outside the angle α relative to the direction D _T, smaller than the angle with respect to the tread width direction D _T of the inclined grooves 100 in the central portion. The central part in the tread width direction _DT is the tire equator line CL when a normal load is applied to the pneumatic tire 10 set to the normal internal pressure specified by the Japan Automobile Tire Association (JATMA). It means in the region of 60% of the tread width.

Further, the circumferential groove 200 is formed only between the inclined grooves 100. That is, the pneumatic tire 10, a continuous circumferential groove is not formed along the tire circumferential direction D _C, the circumferential grooves 200 are separated by inclined grooves 100. The width of the circumferential groove 200 is narrower than the groove width of the inclined groove 100.

Each of the circumferential grooves 200, a circumferential groove 200 adjacent in the tire circumferential direction D _C, is formed at different positions in the tread width direction D _T. Specifically, in the tire circumferential direction D _C, a plurality of circumferential grooves 200 forms a zigzag shape.

(2) Shape of Land Part FIG. 2 is a partially enlarged plan view of the tread of the pneumatic tire 10. As shown in FIG. 2, between the inclined groove 100 formed at predetermined intervals along the tire circumferential direction D _C, circumferential groove 200 is formed. The circumferential groove 200 is formed in a region outside the tread width direction _DT .

Further, the inclined groove 100 communicates with an inclined groove 110 (adjacent inclined groove) adjacent to the inclined groove 100 and located on the center side of the radius of curvature of the inclined groove 100 from the end on the center side in the tread width direction _DT of the inclined groove 100. A communication groove 300 is formed. The communication groove 300 communicates with the inclined groove 110 so as to be orthogonal to the inclined groove 110. Further, due to the shapes of the inclined groove 100 and the communication groove 300, a zigzag land portion 40 is formed at the center portion in the tread width direction _DT .

Between the inclined grooves 100 in the tire circumferential direction D _C , a plurality of zigzag zigzag sipes 410 extending in the tread width direction D _T and a plurality of linear sipes 420 extending in the tire circumferential direction D _C between the plurality of zig zag sipes 410 Is formed. Note that the pneumatic tire 10 may be formed with a sipe (not shown).

Further, formed in both regions in the tread width direction D _T relative to the tire equator line CL, the center portion of the tread width direction D _T including the tire equator line CL, a plurality of straight lines extending in the tread width direction D _T A straight sipe 430 is formed. The groove widths of the zigzag sipe 410, the straight sipe 420, and the straight sipe 430 are narrower than those of the inclined groove 100 and the circumferential groove 200.

(3) Advantageous Effects According to the pneumatic tire 10, the inclined groove 100 extends while curving toward the tread widthwise direction D _T outwardly from the central portion of the tread width direction D _T. Further, the circumferential groove 200 is formed only between the inclined grooves 100.

  For this reason, while the drainage property, particularly the resistance to the hydroplaning phenomenon, is enhanced by the inclined groove 100, the snow column shear force is increased by the region surrounded by the inclined groove 100 and the circumferential groove 200, and the traction on the snow can be improved. Specifically, the lug groove portion of the inclined groove 100 retains the edge component, and thus contributes to improvement of snow traction. In addition, the snow that has entered the inclined groove 100 and the circumferential groove 200 collides with each other at the communication portion between the inclined groove 100 and the circumferential groove 200, thereby increasing the snow column shear force and improving the traction on the snow.

  That is, according to the pneumatic tire 10, in a tire having a narrow tire width and a large tire diameter, performance on wet roads and icy and snow roads equivalent to conventional general tires can be ensured.

In this embodiment, each of the circumferential grooves 200, a circumferential groove 200 adjacent in the tire circumferential direction D _C, is formed at different positions in the tread width direction D _T. Specifically, the circumferential grooves 200 adjacent in the tire circumferential direction D _C is a zigzag shape in the tire circumferential direction D _C. For this reason, the snow that has entered the inclined groove 100 and the circumferential groove 200 collides with each other at the communicating portions of the inclined groove 100 and the circumferential groove 200, thereby increasing the snow column shear force and further improving the traction on the snow. To do.

  In the present embodiment, the communication groove 300 communicates with the inclined groove 110 so as to be orthogonal to the inclined groove 110 (adjacent inclined groove). For this reason, drainage and traction on snow can be secured while securing the rigidity of the land portion between the inclined grooves 110. When the communication groove 300 is not orthogonal to the inclined groove 110, the rigidity of the land portion is lowered, which is not preferable.

In the present embodiment, the width of the circumferential groove 200 is narrower than the groove width of the inclined groove 100. A zigzag sipe 410 and a straight sipe 420 are formed in the land portion between the inclined grooves 110, and a straight sipe 430 is formed in the center portion in the tread width direction _DT . Such a shape can further improve snow traction.

(4) Other Embodiments As described above, the contents of the present invention have been disclosed through the embodiments of the present invention. However, it is understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. Should not. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  For example, in the above-described embodiment, the zigzag sipe 410, the straight sipe 420, and the straight sipe 430 are formed. However, such a sipe does not necessarily have to be formed.

  In the embodiment described above, the communication groove 300 communicates with the inclined groove 110 so as to be orthogonal to the inclined groove 110. However, the communication groove 300 does not necessarily have to be orthogonal to the inclined groove 110. .

In the embodiment described above, the central portion of the tread width direction _DT is the tread including the tire equator line CL in a state where a normal load is applied to the pneumatic tire 10 set to a normal internal pressure defined by JATMA or the like. In the case of a pneumatic tire that is assumed to be mounted on a car with a large camber angle, a normal load is applied to the pneumatic tire set to the normal internal pressure. It may also mean a region of 60% of the “contact width” of the tread with respect to the center in the tread width direction.

  As described above, the present invention naturally includes various embodiments that are not described herein. Therefore, the technical scope of the present invention is determined only by the invention specifying matters according to the scope of claims reasonable from the above description.

10 ... Pneumatic tire
40 ... Land
100 ... Inclined groove
110 ... Inclined groove
200 ... Circumferential groove
300 ... Communication groove
410 ... Zigzag sipe
420 ... Linear sipe
430 ... straight sipe

Claims (7)

A plurality of inclined grooves that are inclined with respect to the tire circumferential direction are formed in the tire circumferential direction, and a plurality of circumferential grooves extending in the tire circumferential direction are formed, and the tire width SW and the tire outer diameter OD are SW ≦ 175 mm, And a tire satisfying the relationship of OD / SW ≧ 3.6,
The inclined groove extends while curving from the center in the tread width direction toward the outside in the tread width direction,
The angle with respect to the tread width direction of the inclined groove other than the central portion is smaller than the angle with respect to the tread width direction of the inclined groove in the central portion,
The circumferential groove is a tire formed only between the inclined grooves.   The tire according to claim 1, wherein each of the circumferential grooves is formed at a position different from a circumferential groove adjacent in the tire circumferential direction in a tread width direction.   The communication groove that is adjacent to the inclined groove and communicates with the adjacent inclined groove located on the center side of the radius of curvature of the inclined groove is formed from an end of the inclined groove on the central portion side. The described tire.   The tire according to any one of claims 1 to 3, wherein the communication groove communicates with the adjacent inclined groove so as to be orthogonal to the adjacent inclined groove.   The tire according to any one of claims 1 to 4, wherein a width of the circumferential groove is narrower than a width of the inclined groove. Between the inclined grooves in the tire circumferential direction,
A plurality of zigzag sipes extending in the tread width direction;
The tire according to any one of claims 1 to 5, wherein a plurality of linear sipes extending in the tire circumferential direction are formed between the plurality of zigzag sipes.   The inclined groove is formed in both regions in the tread width direction with respect to the tire equator line, and a plurality of linear sipes extending in the tread width direction are formed in the central portion including the tire equator line. The tire according to any one of claims 1 to 6.

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