JP2013023192A - Tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire capable of establishing high-dimensional compatibility between performance on a wet road and performance on a snowy and icy road.SOLUTION: In the pneumatic tire 10, an inclined groove 100 is curved to get closer to a tread width direction Dtoward the outside of the tread width direction D; and a branched circumferential groove 200, which branches off from an intermediate portion of the inclined groove 100 and which is elongated along a circumferential direction Dof the tire, is formed. In the branched circumferential groove 200, a portion, which crosses an inclined groove 100 adjacent to the inclined groove 100 serving as a branch source and which is curved so that the center of the radius of curvature of the branched circumferential groove 200 can be positioned on the inside of the tread width direction with respect to the branched circumferential groove 200, and a portion, which is curved so that the center of the radius of curvature of the branched circumferential groove 200 can be positioned on the outside of the tread width direction with respect to the branched circumferential groove 200, are alternately repeated in the circumferential direction Dof the tire.

Description

  The present invention relates to a tire in which circumferential grooves extending in the tire circumferential direction are formed and a plurality of inclined grooves that are inclined with respect to the tire circumferential direction are formed.

  2. Description of the Related Art Conventionally, various tread patterns are used in pneumatic tires (hereinafter referred to as tires) mounted on passenger cars and the like in order to achieve both performance on wet roads and icy and snowy roads. For example, a tire is known in which a circumferential groove extending in the tire circumferential direction is formed on the outer side in the tread width direction, and a plurality of inclined grooves that are inclined with respect to the tire circumferential direction are formed in the center portion in the tread width direction ( Patent Document 1).

  Further, the inclined groove communicates with the circumferential groove. The combination of such circumferential grooves and inclined grooves improves the traction and braking force on snow while ensuring drainage.

Japanese Patent Laid-Open No. 2007-161057 (FIG. 1)

  However, with the recent improvement in performance of passenger cars, there has been a demand for tires that achieve higher performance on wet roads and icy and snowy roads.

  Therefore, the present invention has been made in view of such a situation, and an object thereof is to provide a tire capable of achieving both higher performance on wet roads and icy and snowy roads.

The present invention is characterized in that circumferential grooves (circumferential grooves 20, 30) extending in the tire circumferential direction (tire circumferential direction D _C ) are formed in a region outside the tread width direction (tread width direction D _T ) and the tread. A plurality of inclined grooves (inclined grooves 100) extending from the center in the width direction to the outer side in the tread width direction and inclined with respect to the tire circumferential direction are formed, and the outer ends in the tread width direction of the inclined grooves communicate with the circumferential groove. In the tire (pneumatic tire 10), the inclined groove is curved so as to approach the tread width direction toward the outer side in the tread width direction, branches from an intermediate portion of the inclined groove, and extends along the tire circumferential direction. A branch circumferential groove extending in the tread width direction, which intersects with the inclined groove adjacent to the branch source slope groove, and is located on the inner side in the tread width direction of the branch circumferential groove. The center of the radius is located And the portion that curves so that the center of the radius of curvature of the branch circumferential groove is located on the outer side in the tread width direction than the branch circumferential groove is alternately repeated in the tire circumferential direction. And

  According to the characteristics of the present invention, it is possible to provide a tire capable of achieving both higher performance on wet roads and icy and snowy roads.

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, a circumferential groove 20 and a circumferential groove 30 are formed in the pneumatic tire 10.

  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.

Circumferential groove 20, 30, in the tread width direction D _T outside the region, extending in the tire circumferential direction D _C. Between the circumferential groove 20 and the circumferential groove 30, a land portion 40 that is in contact with the road surface is provided.

The land portion 40 is provided in the central portion in the tread width direction _DT . 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.

A plurality of inclined grooves 100 are formed in the land portion 40. Inclined groove 100 is curved so as to approach the tread width direction D _T As the outward tread width direction D _T. The outer end of the inclined groove 100 in the tread width direction _DT communicates with the circumferential groove 20 (or the circumferential groove 30).

Further, the land portion 40 is formed with a plurality of branch circumferential grooves 200. Branch circumferential groove 200 is branched from an intermediate portion of the inclined groove 100, extending along the tire circumferential direction D _C. Note that the pneumatic tire 10 may be formed with a sipe (not shown).

(2) Shape of Land Part FIG. 2 is a partially enlarged plan view of the tread of the pneumatic tire 10. In FIG. 2, the inclined groove 100 will be described taking the inclined groove 110 to the inclined groove 140 as an example. Further, the branch circumferential groove 200 will be described taking the branch circumferential groove 210 to the branch circumferential groove 240 as examples.

For example, the formation position of the inclined grooves 110 in the tire circumferential direction D _C is the one side of the region relative to the tire equator line CL, are different in the region of the other side. Specifically, the formation position of the inclined groove 110 is deviated from the formation position of the inclined groove 120 formed on the other side with respect to the tire equator line CL. Further, the groove width of the inclined groove 110 becomes wider toward the outside of the tread width direction _DT .

On the other hand, for example, branched circumferential groove 210 intersects the inclined groove 130 adjacent in the tire circumferential direction D _C to branch origin inclined groove 110. Similarly, the other side relative to the tire equator line CL, branched circumferential groove 220 intersects the inclined groove 140 adjacent in the tire circumferential direction D _C to branch origin inclined groove 120.

Further, as described above, the branch circumferential groove 200 includes the branch circumferential groove 210 to the branch circumferential groove 240. For example, the branch circumferential groove 200 is inside the tread width direction D _T than the branch circumferential groove 200. A portion that curves so that the center of the radius of curvature of the branch circumferential groove 200 is located at the center, specifically, a portion of the branch circumferential groove 210 and a branch circumference outside the branch circumferential groove 200 in the tread width direction _DT. A portion that is curved so that the center of the radius of curvature of the directional groove 200 is located, specifically, a branched circumferential groove 230 is included.

The branch circumferential groove 200 is curved so that the center of the radius of curvature of the branch circumferential groove 200 is located inside the tread width direction _DT, and the radius of curvature of the branch circumferential groove 200 is outside the tread width direction _DT . center and a portion which is curved so as to be positioned, alternately in the tire circumferential direction D _C.

Similarly, on the other side with respect to the tire equator line CL, the branch circumferential groove 200 is a curved portion (branch circumferential direction) so that the center of the radius of curvature of the branch circumferential groove 200 is located inside the tread width direction _DT. grooves 230 and), and a portion curved to the radius of curvature of the center of the tread width direction D _T branch circumferential groove 200 on the outside is located (branch circumferential groove 220), alternately in the tire circumferential direction D _C.

  Further, for example, one end of the branch circumferential groove 210 communicates with the inclined groove 130 so as to be orthogonal to the inclined groove 130, and the groove width of the branch circumferential groove 210 increases toward the communication portion with the inclined groove 130. Narrow.

Furthermore, in the present embodiment, on the tire equator line CL, the circumferential-direction narrow grooves 300 extending in the tire circumferential direction D _C is formed. The ends of the inclined grooves 110 to 140 inside the tread width direction _DT communicate with the circumferential narrow groove 300.

(3) Advantageous Effects According to the pneumatic tire 10, the inclined groove 100 is curved so as to approach the tread width direction D _T As the outward tread width direction D _T, the tread of the branch circumferential grooves 200 width direction D _T portion radius of curvature of the center of the inner branch circumferential groove 200 is curved so as to be located (e.g., branched circumferential groove 210) branches, in the tread width direction D _T outside the branch circumferential grooves 200 portion radius of curvature of the center of the circumferential groove 200 is curved so as to be located (e.g., branched circumferential groove 230) but with repeated alternately in the tire circumferential direction D _C.

  For this reason, since the snow which entered into these groove parts formed in the land part 40 is controlled for escape, the snow column shear force increases as a result. Therefore, the traction and braking force on an icy and snowy road are improved. Specifically, since the rotational direction of the pneumatic tire 10 is specified, the snow that has entered the groove portion is dammed up at the tip of the inclined groove 100 or the like during braking, so that the braking force is improved. Further, at the time of starting acceleration, snow collides with each other at the intersection between the inclined groove 100 and the branched circumferential groove 200, so that traction is improved.

  In addition, since the inclined groove 100 communicates with the circumferential grooves 20 and 30, rainwater that has entered the land portion 40 can be efficiently drained.

  That is, according to the pneumatic tire 10, the performance on wet roads and icy and snowy roads can be achieved at high levels.

In the present embodiment, the end of the inclined groove 100 inside the tread width direction _DT communicates with the circumferential narrow groove 300. For this reason, the snow that has entered these groove portions formed in the land portion 40 is further restricted from escape at the junction of the circumferential narrow groove 300 and the inclined groove 100, so the snow column shear force further increases. In addition, traction on icy and snowy roads can be further improved.

In the present embodiment, the groove width of the inclined groove 100 becomes wider toward the outside of the tread width direction _DT . Further, one end of the circumferential narrow groove 300 communicates with the inclined groove 100 so as to be orthogonal to the inclined groove 100, and the groove width of the circumferential narrow groove 300 becomes narrower toward the communicating portion with the inclined groove 100. . Therefore, the snow that has entered the inclined groove 100 and the circumferential narrow groove 300 from the outside of the tread width direction _DT gradually narrows and intersects with the other inclined grooves 100. The Therefore, it can contribute to further improvement of traction and braking force on an icy and snowy road.

(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 embodiment of the present invention, the groove width of the inclined groove 100 and the groove width of the circumferential narrow groove 300 are changed, but the groove width may be constant without changing.

In the embodiment described above, the inner end of the inclined groove 100 in the tread width direction _DT communicates with the circumferential narrow groove 300, but the circumferential narrow groove 300 may not necessarily be formed.

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
20 ... Circumferential groove
25, 35… Bend
30 ... Circumferential groove
40 ... Land
100, 110, 120, 130, 140 ... inclined grooves
200, 210, 220, 230, 240 ... Branch circumferential groove
300 ... circumferential narrow groove

Claims (4)

A circumferential groove extending in the tire circumferential direction is formed in the outer region in the tread width direction, and a plurality of inclined grooves extending outward from the center portion in the tread width direction and inclined with respect to the tire circumferential direction are formed.
The tread width direction outer end of the inclined groove is a tire communicated with the circumferential groove,
The inclined groove is curved to approach the tread width direction as it goes outward in the tread width direction,
A branch circumferential groove that branches off from the middle portion of the inclined groove and extends along the tire circumferential direction is formed,
The branch circumferential groove is
Intersects the inclined groove adjacent to the branching inclined groove,
A portion that is curved so that the center of the radius of curvature of the branch circumferential groove is located on the inner side in the tread width direction than the branch circumferential groove, and the branch circumferential groove on the outer side in the tread width direction than the branch circumferential groove. A tire that repeats alternately in the tire circumferential direction a portion that is curved so that the center of the radius of curvature is located. On the tire equator line, a circumferential narrow groove extending in the tire circumferential direction is formed,
The tire according to claim 1, wherein an end of the inclined groove on the inner side in the tread width direction communicates with the circumferential narrow groove.   The tire according to claim 1 or 2, wherein a groove width of the inclined groove becomes wider toward the outer side in the tread width direction.   The one end of the branched circumferential groove communicates with the inclined groove so as to be orthogonal to the inclined groove, and the groove width of the branched circumferential groove becomes narrower toward the communicating portion with the inclined groove. The tire according to any one of 1 to 3.

Images