JP5774923B2 - tire - Google Patents

Description

  The present invention relates to a tire provided with a land block formed with an inclined groove that is inclined with respect to the tire circumferential direction and partitioned by the inclined groove.

  Conventionally, various pneumatic tread patterns (hereinafter referred to as tires) mounted on vehicles such as automobiles have been proposed with various tread patterns aiming to achieve both drainage and traction capability on wet road surfaces.

  For example, a tire is known in which an inclined groove that is inclined with respect to the tire circumferential direction and is curved in an S shape is formed from the center in the tread width direction to the tread shoulder (see Patent Document 1). The inclined groove extends to the tread shoulder without branching and joining with other grooves.

  Moreover, the land block divided by such an inclined groove has a wide part with a wide width and a constricted part with a narrower width than the wide part.

  According to such a tire, since the inclined groove does not branch and extends to the tread shoulder without joining with other grooves, the turbulence of the water flow at the joining or branching portion of the grooves does not occur. Therefore, rainwater that has entered the tread portion is efficiently drained from the tread shoulder to the outside of the tread portion through the inclined groove.

  Further, the land block having the wide portion and the constricted portion continuously changes the angle formed by the edge portion of the land block and the steering direction of the tire when the land block is stepped on and kicked out. Regardless of the steering direction, it exhibits a certain traction ability.

JP 2000-238511 A (page 3-4, FIG. 1)

  However, the conventional tire described above has the following problems. That is, the inclined groove extends to the tread shoulder without branching and joining with other grooves, so that there is no disturbance of water flow at the joining or branching portion of the groove, but the ground surface of the land block ( The drainage destination of rainwater entering between the surface) and the road surface is limited to the inclined groove. For this reason, further improvement has been sought for the drainage of rainwater that has entered between the ground surface of the land block and the road surface.

  Therefore, the present invention has been made in view of such a situation, and the inclined groove inclined with respect to the tire circumferential direction does not branch and extends to the tread shoulder without joining with other grooves. The purpose of the present invention is to provide a tire with improved drainage on the surface of the land block defined by the inclined groove.

The present invention is characterized in that an inclined groove (inclined groove 100) inclined with respect to the tire circumferential direction (tire circumferential direction D _C ) is formed, and a land block (land block 200) partitioned by the inclined groove. The inclined groove is formed up to a tread shoulder (tread shoulder 40) without branching and joining with other grooves without branching, and the land portion block includes the land portion. A wide part (wide part 230) having a predetermined width along the short direction of the block, and a narrow part (narrow part) having a width along the short direction of the land block smaller than the wide part 260), and a surface (surface 200a) of the land block facing the road surface on which the tire contacts the ground is provided with a plurality of convex portions (convex portions 241, 242, 270), , Extending along the direction in which the inclined groove is formed, and provided in the wide portion The number of first convex portions (convex portions 241 and 242) that are the convex portions to be provided is larger than the number of second convex portions (convex portions 270) that are the convex portions provided in the narrow portion. And

  In the above-described feature of the present invention, the plurality of first protrusions may be continuous with the second protrusion.

In the above-described feature of the present invention, the land portion block includes the narrow portion and the wide portion from the central portion (central portion 20) side in the tread width direction (tread width direction D _T ) toward the tread shoulder. May be provided in order.

  In the above-described feature of the present invention, the land block is provided closer to the center in the tread width direction than the narrow portion, and the width along the short direction of the land block is larger than the narrow portion. You may further have a wide center wide part (center wide part 210).

  In the above-described feature of the present invention, the distal end portion (the distal end portion 211) of the central wide portion may have a tapered shape that becomes thinner toward the distal end of the land block.

  In the characteristics of the present invention described above, a circumferential groove (circumferential groove 30) extending along the tire circumferential direction is formed, and the circumferential groove is formed at a position including a tire equator line (tire equator line CL), The inclined groove may communicate with the circumferential groove.

  According to the feature of the present invention, when the inclined groove inclined with respect to the tire circumferential direction extends to the tread shoulder without branching and joining with other grooves, the land portion defined by the inclined groove is provided. A tire having improved drainage on the surface of the block can be provided.

1 is a schematic front view of a pneumatic tire 10 according to an embodiment of the present invention. 1 is a single perspective view of a land block 200 according to an embodiment of the present invention. It is sectional drawing of the land part block 200 which concerns on embodiment of this 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 schematic front view of a pneumatic tire 10 according to this embodiment. As shown in FIG. 1, it is assumed that the pneumatic tire 10 is mainly mounted on a Sport Utility Vehicle (SUV). The pneumatic tire 10 may be filled with an inert gas such as nitrogen gas instead of air.

In the pneumatic tire 10, a circumferential groove 30 is formed in the central portion 20 in the tread width direction _DT . Specifically, the circumferential groove 30 is formed at a position including the tire equator line CL. The pneumatic tire 10 has a generally symmetrical tread pattern with respect to the tire equator line CL. The central portion 20 in the tread width direction _DT is a tread width in a state where a normal load is applied to the pneumatic tire 10 set to a normal internal pressure defined by the Japan Automobile Tire Association (JATMA) or the like. It means a region having a width of 1/3 of the tread width including the tire equator line CL.

Circumferential groove 30 is a straight shape extending along the tire circumferential direction D _C. However, the side edge portion 30a of the circumferential groove 30 in the tread width direction _DT is curved so as to meander in the tread width direction _{DT due} to the shape of a land block 200 described later.

Further, the pneumatic tire 10 is formed with an inclined groove 100 that is inclined with respect to the tire circumferential direction D _C (tire equator line CL). The inclined groove 100 is formed up to the tread shoulder 40 without branching at all and without joining with other grooves. A pair of sidewalls 50 are provided on the outer side of the tread shoulder 40 in the tread width direction _DT .

Further, the end of the inclined groove 100 on the tire equator line CL side communicates with the circumferential groove 30. The tread shoulder 40 means a tread end portion in the tread width direction _DT that does not come into contact with the road surface 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.

The pneumatic tire 10 includes a land portion blocks 200 partitioned by the inclined groove 100 which is multiply formed in this manner provided a predetermined distance in the tire circumferential direction D _C. Land portion blocks 200 is a portion that may contact with a road surface, it is formed with a plurality in the tire circumferential direction D _C. Further, the land block 200 is provided in each of the two regions based on the tire equator line CL.

(2) Shape of Land Block Next, the shape of the land block 200 will be described with reference to FIGS. 2 and 3 (a) to 3 (d). FIG. 2 is a single perspective view of the land block 200. 3A to 3D are cross-sectional views of the land block 200. FIG. Specifically, FIG. 3A is a cross-sectional view along the short direction of the land block 200 at the position shown in FIG. Similarly, FIGS. 3B to 3D are cross-sectional views along the short direction of the land block 200 at the positions (b) to (d) shown in FIG.

  As shown in FIG. 2 and FIGS. 3A to 3D, in this embodiment, the land block 200 includes a central wide portion 210, a wide portion 230, and a narrow portion 260.

The central wide portion 210 is provided closer to the center in the tread width direction D _T than the narrow portion 260. The central wide portion 210 has a width (width at the position (d)) along the short direction of the land block 200 wider than the narrow portion 260. Further, the front end portion 211 of the central wide portion 210 has a tapered shape that becomes thinner as going to the front end of the land block 200.

  The wide portion 230 has a predetermined width along the short side direction of the land block 200. Specifically, the width of the wide portion 230 depends on the size of the pneumatic tire 10 (tread width and tire diameter), but a range of 1.5 ≦ (width of the wide portion 230 / width of the narrow portion 260) ≦ 4. It is preferable that

  The narrow portion 260 has a width (width at the position (c)) along the short direction of the land block 200 that is narrower than the wide portion 230. The width of the narrow portion 260 depends on the size of the pneumatic tire 10 (tread width and tire diameter), but may be 1.5 ≦ (width of the wide portion 230 / width of the narrow portion 260) ≦ 4. preferable.

The land portion block 200 is provided in the order of the narrow portion 260 and the wide portion 230 from the central portion 20 side in the tread width direction _DT toward the tread shoulder 40. In the present embodiment, since the central wide portion 210 is provided, the land block 200 is arranged in the order of the central wide portion 210, the narrow portion 260, and the wide portion 230 from the central portion 20 side toward the tread shoulder 40. Provided. That is, the central wide portion 210 is continuous with the narrow portion 260, and the narrow portion 260 is continuous with the wide portion 230.

  In this way, the land portion block 200 connected in the order of the central wide portion 210, the narrow portion 260, and the wide portion 230 has a shape constricted in the narrow portion 260 because the inclined groove 100 is curved in an S shape. .

The surface 200a of the land block 200 facing the road surface on which the pneumatic tire 10 contacts is provided with a plurality of convex portions. Specifically, the wide part 230 includes a convex part 241 and a convex part 242 (first convex part). The narrow portion 260 is provided with a convex portion 270 (second convex portion). The convex portions 241, 242, 270 extend along the direction in which the inclined groove 100 is formed. Specifically, the convex portions 241, 242, and 270 are inclined with respect to the tire circumferential direction D _C (tire equator line CL) in the same manner as the inclined groove 100, and the central portion 20 side in the tread width direction D _T To the tread shoulder 40.

  Further, the number of convex portions provided in the wide portion 230 is larger than the number of convex portions provided in the narrow portion 260. In the present embodiment, the wide portion 230 is provided with two convex portions (the convex portions 241 and 242), and the narrow portion 260 is provided with one convex portion (the convex portion 270).

  Furthermore, in the present embodiment, the central wide portion 210 is provided with one convex portion, specifically, the convex portion 221.

  The two convex portions 241 and 242 are continuous with the convex portion 270. Specifically, the convex portions 241 and 242 branch in a Y shape so as to branch into two from the convex portion 270. Further, in the region where the convex portions 241 and 242 branch into two from the convex portion 270, there is no angular portion, and the surface 200a of the land block 200 is smooth from one convex portion to two convex portions. Has changed.

  Similarly, there is no angular portion at the ends of the convex portions 241 and 242 in the wide portion 230, and the surface 200a of the land block 200 is changed from a shape having two convex portions to a smooth shape having no convex portions. It is changing smoothly. The same applies to the end of the convex part 221 in the central wide part 210.

  As shown in FIGS. 3A to 3D, at the position (a) of the land block 200, the entire surface 200a of the wide portion 230 can be in contact with the road surface. Similarly, at the position (d) of the land block 200, the entire surface 200a of the central wide portion 210 can come into contact with the road surface.

  Since the convex portions 241 and 242 are provided at the position (b) of the land portion block 200, only the vertex portion 241a of the convex portion 241 and the vertex portion 242a of the convex portion 242 can be in contact with the road surface. Similarly, since the convex portion 270 is provided at the position (c) of the land portion block 200, only the top portion 270a of the convex portion 270 can be in contact with the road surface. That is, in the portion where the convex portion is provided, only the apex portion of the convex portion can be in contact with the road surface. That is, the land portion block 200 other than the apex portion is recessed toward the groove bottom 100a side of the adjacent inclined groove 100.

(3) Action / Effect According to the pneumatic tire 10, the inclined groove 100 is formed up to the tread shoulder 40 without branching and joining with other grooves. For this reason, the basic drainage property of the rainwater which entered the tread can be secured. Furthermore, since a plurality of convex portions (convex portions 241, 242, 270) are provided on the surface of the land portion block 200, rainwater enters the recesses between the convex portions, and the land portion block 200 passes through the recesses. The rain water on the surface 200a of the water can be guided to the inclined groove 100. For this reason, the drainage property on the surface 200a of the land block 200 can be secured.

  Furthermore, since the number of convex portions (first convex portions) provided in the wide portion 230 is larger than the number of convex portions (second convex portions) provided in the narrow portion 260, the drainage performance in the wide portion 230 is further increased. improves.

That is, according to the pneumatic tire 10, when extending to the tread shoulder 40 without inclined grooves 100 inclined relative to the tire circumferential direction D _C merges with another groove without branching, inclined grooves 100 The drainage performance on the surface 200a of the land block 200 partitioned by the is improved.

  Further, the surface shape of such a land block 200 has a minimum ground contact area when cruising an automobile equipped with the pneumatic tire 10, and the load applied to the pneumatic tire 10 during braking, acceleration or cornering of the automobile. Accordingly, the ground contact area increases. For this reason, it is possible to contribute to an increase in grip force of the pneumatic tire 10 during braking, acceleration, or cornering.

  Further, according to the pneumatic tire 10, since the land block 200 has the wide portion 230 and the narrow portion 260, the edge portion of the land block 200 and the pneumatic tire when the land block 200 is stepped on and kicked out. The angle formed by the 10 steering directions changes continuously, and exhibits a certain traction ability regardless of the steering direction of the pneumatic tire 10.

  In the present embodiment, the convex portions 241 and 242 are continuous with the convex portion 270. Specifically, the convex portions 241 and 242 branch in a Y shape so as to branch into two from the convex portion 270. Further, in the region where the convex portions 241 and 242 branch into two from the convex portion 270, there is no angular portion, and the surface 200a of the land block 200 is smooth from one convex portion to a shape having two convex portions. Has changed. For this reason, the disturbance of the water flow on the surface 200a of the land block 200 is suppressed, and rainwater on the surface 200a can be drained smoothly.

  In the present embodiment, the land portion block 200 is provided in the order of the narrow portion 260 and the wide portion 230 from the central portion 20 side toward the tread shoulder 40. Furthermore, in the present embodiment, the land block 200 has a central wide portion 210 whose tip portion 211 is tapered closer to the center in the tread width direction DT than the narrow portion 260.

  For this reason, the edge portion of the land block 200 and the steering of the pneumatic tire 10 are secured while ensuring smooth drainage of rainwater from the central portion 20 side toward the tread shoulder 40 by the inclined groove 100 curved in an S shape. The angle formed by the direction can be changed in various ways, and it is easy to exert a certain traction ability regardless of the steering direction of the pneumatic tire 10.

  In the present embodiment, the inclined groove 100 communicates with the circumferential groove 30. For this reason, rainwater entering the central portion 20 can be easily discharged to the tread shoulder 40 via the inclined groove 100, and the drainage of the pneumatic tire 10 can be further improved.

(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 inclined groove 100 communicates with the circumferential groove 30, but the inclined groove 100 does not necessarily need to communicate with the circumferential groove 30. Further, the circumferential groove 30 may not be formed.

  In the embodiment described above, the land portion block 200 has the central wide portion 210, but may have a shape without the central wide portion 210. In the above-described embodiment, the narrow portion 260 and the wide portion 230 are provided in the order from the central portion 20 side toward the tread shoulder 40. However, the order may be reversed.

  In the above-described embodiment, the wide portion 230 is provided with two convex portions (the convex portions 241 and 242), and the narrow portion 260 is provided with one convex portion 270. The number is not limited to the embodiment. For example, the wide portion 230 may include three convex portions, and the narrow portion 260 may include two convex portions 270.

  In the above-described embodiment, it is assumed that the pneumatic tire 10 is mainly mounted on a Sport Utility Vehicle (SUV), but the scope of application of the present invention is not limited to such a pneumatic tire.

  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 ... Central part
30 ... Circumferential groove
30a ... Side edge
40 ... tread shoulder
50… Sidewall
100 ... Inclined groove
100a ... groove bottom
200 ... Land block
200a ... surface
210 ... Wide center part
211… The tip
221 ... Convex
230 ... Wide part
241, 242 ... Convex
241a, 242a… vertical part
260 ... Narrow part
270 ... convex
270a… Top part

Claims (8)

An inclined groove that is inclined with respect to the tire circumferential direction is formed, and a tire including a land block defined by the inclined groove,
The inclined groove is formed up to the tread shoulder without branching and joining with other grooves without branching,
The land block is
A wide portion having a predetermined width along the short direction of the land block;
A width along the short direction of the land block has a narrow part narrower than the wide part,
On the surface of the land block facing the road surface on which the tire touches, a plurality of convex portions are provided,
The convex portion extends along the direction in which the inclined groove is formed,
The surface of the land block has changed from a shape having the convex portion to a smooth shape not having the convex portion so as to be continuous without a step along the formation direction of the inclined groove,
The number of first convex portions that are the convex portions provided in the wide portion is greater than the number of second convex portions that are the convex portions provided in the narrow portion.   The tire according to claim 1, wherein the plurality of first protrusions are continuous with the second protrusion. The tire according to claim 2, wherein the first convex portion is formed by branching in a Y shape from the second convex portion. The surface of the land block changes from a shape including the second convex portion to a shape including the first convex portion so as to be continuous without a step along the formation direction of the inclined groove. Item 4. The tire according to Item 3.   The tire according to claim 1, wherein the land block is provided in the order of the narrow portion and the wide portion from a central portion side in the tread width direction toward the tread shoulder. Wherein the land portion blocks, with provided near the center in the tread width direction than the narrow portion further has a wide central wide portion than the width along the lateral direction is the narrow portion of the land portion blocks Item 6. The tire according to Item 5 . The tire according to claim 6 , wherein a distal end portion of the central wide portion has a tapered shape that becomes narrower toward a distal end of the land block. A circumferential groove extending along the tire circumferential direction is formed,
The circumferential groove is formed at a position including the tire equator line,
The tire according to claim 1, wherein the inclined groove communicates with the circumferential groove.

Images