WO2016199774A1

WO2016199774A1 - Tire

Info

Publication number: WO2016199774A1
Application number: PCT/JP2016/066951
Authority: WO
Inventors: 賢二金子
Original assignee: 株式会社ブリヂストン
Priority date: 2015-06-10
Filing date: 2016-06-07
Publication date: 2016-12-15
Also published as: JP2017001523A

Abstract

In order to improve both snow driving performance and wear performance of a tire, shoulder blocks 18 defined by shoulder grooves 14 and lug grooves 15 are provided with: a widthwise groove 20 which extends in a direction intersecting the tire circumferential direction, with one end opening towards the tread ground-contact end TG and the other end terminating in the shoulder block 18; at least one or more sipes 19c which are formed on the surface of the shoulder block 18 to one side and to the other side of the widthwise groove 20 in the tire circumferential direction and which extend in a direction that intersects the tire circumferential direction; and a communicating sipe 21 which allows communication between the end of the widthwise groove 20 and either the shoulder groove 14 or the tread ground-contact end.

Description

tire

The present invention relates to a tire in which a sipe is formed on the tire tread surface side of a block, and more particularly, to a tire that improves both running performance on snow and wear resistance.

Conventionally, as a tread pattern of a studless tire, in order to improve the running performance on snow, a lug groove extending in a direction intersecting the circumferential groove is provided, and a sipe is provided on the surface of the block defined by the circumferential groove and the lug groove. Many formed are used (see, for example, Patent Document 1).
In patent document 1, while arranging the lug groove which divides the block located in a tire center part by turns at a staggered angle with respect to a tire peripheral direction, it forms a sipe extended in a direction parallel to a tire width direction. In addition, it is said that it is possible to improve both the drainage performance during running on wet roads and the running performance on snow.

JP 2009-173211 A

However, in the tire of Patent Document 1, since many sipes extending in the tire width direction are arranged, the edge component in the circumferential direction can be ensured, but conversely, the block rigidity is reduced, so that the deformation of the block increases. As a result, there is a problem that the wear resistance performance is degraded and the edge effect is also concerned about the degradation.
Moreover, it cannot be said that the drainage performance is sufficient only by the configuration in which the lug grooves defining the blocks are alternately arranged at different angles with respect to the tire circumferential direction.

The present invention has been made in view of conventional problems, and an object of the present invention is to provide a tire that can improve both running performance on snow and wear resistance.

The present invention includes at least three circumferential grooves formed on the surface of the tread so as to extend along the tire circumferential direction, lug grooves extending in a direction intersecting the circumferential groove, and the circumferential grooves. A tire having a plurality of blocks defined by the lug grooves, wherein the blocks extend in a direction intersecting the tire circumferential direction, and one end of the tire is a tire width of the circumferential grooves defining the blocks. A circumferential groove on the outer side in the direction, or a widthwise groove that opens at the tread grounding end and the other end terminates inside the block, and one side of the widthwise groove in the tire circumferential direction on the surface of the block And at least one sipe extending in a direction intersecting with the tire circumferential direction formed on the other side, and a terminal end of the width direction groove and a circumferential groove or tread grounding end located on the terminal end side. Pass Characterized in that it comprises a communication sipes.

It should be noted that the summary of the invention does not list all necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

It is a figure which shows the tread pattern of the tire which concerns on this Embodiment. It is a figure which shows the relationship between the inclination of a lug groove, and the inclination of a width direction groove | channel and a sipe. It is a figure which shows the detail of a width direction groove | channel. It is a figure which shows the other example of the width direction groove | channel and communication sipe by this invention.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a diagram illustrating an example of a tread pattern of a tire 10 according to the present embodiment. The direction from the upper side to the lower side in the figure is the tire rotation direction, the upper side in the figure is the kicking side, and the lower side is the stepping side. Further, in the figure, the left-right direction is the tire width direction, CL is the tire equatorial plane, TG is the tread ground contact end, and the tread is the tread tread portion.
In the figure, 11 is a tread, 12 is a center main groove, 13 is an outer main groove, 14 is a shoulder groove, 15 is a lug groove, 16 is a center block, 17 is a 2nd block, 18 is a shoulder block, and 19a to 19c are sipes. , 20 is a width direction groove, and 21 is a communication sipe.
The center main groove 12, the outer main groove 13, and the shoulder groove 14 are circumferential grooves extending continuously along the tire circumferential direction, and the center main groove 12 is located at the center in the tire width direction. Further, the two outer main grooves 13 are on the outer side in the tire width direction than the center main groove 12, and the two shoulder grooves 14 are on the outer side in the tire width direction with respect to the outer main groove 13, respectively, with respect to the tire equatorial plane CL. It is formed symmetrically.

The lug groove 15 is a groove formed so as to intersect the tire circumferential direction, one end communicating with the center main groove 12 and the other end opening to the tread ground contact end TG which is the end portion of the tread 11 in the tire width direction. Thus, they are respectively provided on the left and right of the tire equatorial plane CL. The right lug groove 15 extends from the lower left to the upper right, and the left lug groove 15 extends from the lower right to the upper left. A center block 16 is defined by the center main groove 12, the outer main groove 13, and the lug groove 15, and a 2nd block 17 is defined by the outer main groove 13, the shoulder groove 14, and the lug groove 15. The shoulder block 18 is partitioned by the shoulder groove 14 and the lug groove 15.
FIG. 2 is a diagram showing the relationship between the inclination of the lug groove and the inclination of the width direction groove and the sipe. In this example, the lug groove 15 has its groove widths W1, W2, W3 as it goes outward in the tire width direction. It is formed to be wide (W1 <W2 <W3). Specifically, the angle θF formed between the extending direction of the groove wall on the stepping end side of the lug groove 15 and the tire width direction is set to be larger than the angle θk formed between the extending direction of the groove wall on the kicking end side and the tire width direction. By enlarging, the groove width of the lug groove 15 is made wider toward the outer side in the tire width direction.
As a result, the angle formed between the extending direction of the groove wall on the stepping end side of each

block

16, 17, 18 partitioned by the lug groove 15 and the tire width direction is θF, and the extending direction of the groove wall on the kicking end side Since the angle formed with the tire width direction is θk, in each

block

16, 17, 18 the angle formed between the extending direction of the groove wall on the stepping end side of the

block

16, 17, 18 and the tire width direction is the kicking It can be seen that the angle is larger than the angle between the extending direction of the groove wall on the protruding end side and the tire width direction. Here, the extending direction of the groove wall is the direction of the tangent of the curve constituting the groove wall, and the angle θF on the stepping end side and the angle θk on the kicking end side are the inclination of the tangent at the same place in the tire width direction Needless to say.
Hereinafter, the angle θF is referred to as a tread side inclination angle, and the angle θk is referred to as a kick side inclination angle.
In this example, in order to make the edge component in the circumferential direction larger than the edge component in the width direction, the step-side inclination angle θF is in the range of 0 ° <θF ≦ 10 °, and the kick-side inclination angle θk The size is in the range of 0 ° ≦ θk ° ≦ 5 °, but is not limited thereto, and may be θk <θF.

The sipe 19a is a sipe formed on the tire tread side of the center block 16, the sipe 19b is a 2nd block 17, and the sipe 19c is a shoulder block 18.
In this example, the sipes 19a to 19c are all 3D sipes having a polygonal shape in plan view and a shape that also bends in the depth direction, and an angle formed between the extending direction of the sipes 19a to 19c and the tire width direction ( Hereinafter, it is formed such that (sipe inclination angle) θs is larger than kick side inclination angle θk and smaller than stepping side inclination angle θF.
In this example, in order to have the edge component in the width direction in addition to the edge component in the circumferential direction, the size of the sipe inclination angle θs is set in the range of 0 ° <θs ≦ 8 °. Instead, it is sufficient if θk <θs <θF.

As shown in FIG. 3A, the width direction groove 20 is provided only in the shoulder block 18 and extends in a direction crossing the tire circumferential direction, and is an end portion on the outer side in the tire width direction (hereinafter referred to as an opening 20a). ) Is open to the tread ground contact end TG, and the inner end in the tire width direction (hereinafter referred to as the end portion 20b) terminates in the shoulder block 18, and the groove depth becomes shallower toward the end portion 20b. Yes. Reference numeral 20c denotes a terminal end portion (outer groove end portion) on the outer side in the tire width direction from the tread ground contact end TG of the width direction groove 20.
In addition, the depth (the distance from the groove bottom of the width direction groove 20 to the tread surface) outside the tire width direction with respect to the tread ground contact end TG of the width direction groove 20 becomes shallower toward the groove outer end portion 20c. . That is, the depth of the width direction groove 20 is deepest in the vicinity of the opening 20a.

The communication sipe 21 is a sipe that communicates with the end portion 20b of the width direction groove 20 and the shoulder groove 14 that is a circumferential groove located on the end portion 20b side. The sipe 19c is provided in the width direction groove 20 and the shoulder block 18; Extend in the same direction.
In this example, the communication sipe 21 is a 1D sipe as shown in FIG. Similar to the widthwise groove 20, the communication sipe 21 is provided substantially at the center in the tire circumferential direction, and therefore does not contribute much to the block rigidity. Therefore, the number of dimensions of the communication sipe 21 may be lower than the number of dimensions of the sipe 19 c provided in the shoulder block 18.

In this example, instead of providing a large number of sipes in the shoulder block 18, by providing the width direction groove 20 having one end portion 20b in the shoulder block 18, a larger edge component than that of the sipes is ensured and the running performance on snow. To ensure.
In general, when the number of sipes is large, the thickness of the small blocks (here, the distance in the circumferential direction) divided by the sipes becomes thin, so that the block rigidity decreases and the collapse of the small blocks increases. , Wear resistance performance decreases.
On the other hand, since the width direction groove 20 of this example has one end terminated in the shoulder block 18, it can suppress a decrease in block rigidity and is open to the tread grounding end TG side. Also, drainage performance can be improved.

In addition, since the end portion 20b of the width direction groove 20 is provided with a communication sipe 21 that communicates with the shoulder groove 14 and extends in the same direction as the width direction groove 20, a local increase in block rigidity can be suppressed. Therefore, the shoulder block 18 is easily deformed, and as a result, the edge effect can be effectively exhibited.
In the width direction groove that also opens to the shoulder groove 14 side, since the block is divided into two, the edge effect and drainage performance can be ensured, but the wear resistance decreases. On the other hand, a widthwise groove that terminates on the tread grounding end TG side is not preferable because drainage performance deteriorates.
Therefore, one end of the width direction groove 20 needs to open to the tread grounding end TG and the other end must end inside the shoulder block 18.

Thus, in the present embodiment, the shoulder block 18 has one end opened to the tread grounding end TG and the other end terminated inside the shoulder block 18, and the width direction groove 20 in the tire circumferential direction. A sipe 19c extending in a direction crossing the tire circumferential direction formed on one side and the other side, and a communication sipe 21 communicating with the end portion 20b of the width direction groove 20 and the shoulder groove 14 are provided. Therefore, drainage performance and wear resistance performance can be improved while ensuring running performance on snow.

As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the embodiment. It is apparent from the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

For example, in the embodiment, the width direction groove 20 is provided only in the shoulder block 18, but the width direction groove 20 may be provided also in the 2nd block 17.
In the above embodiment, the width direction groove 20 having one end opened in the shoulder groove 14 and the other end terminating in the shoulder block 18 is provided and communicated with the shoulder groove 14 and the end portion 20 b of the width direction groove 20. 4 (a) and 4 (b), the shoulder block 18 has one end opened in the shoulder groove 14 and the other end terminated in the shoulder block 18 as shown in FIGS. The same effect can be obtained by providing the communication sipe 21Z that communicates with the terminal end 20k of the width direction groove 20Z and the tread grounding end TG while providing 20Z.
Moreover, in the said embodiment, the sipe 19 was made into the shape of a broken line, However, A wavy sipe may be sufficient. In the above embodiment, all the sipes 19 are 3D sipes. However, the sipes provided in the center block 16 and the 2nd block 17 may be 2D sipes, and only the sipes provided in the shoulder block 18 may be 3D sipes. .
In short, the sipes formed in the block provided with the width direction groove 20 are respectively arranged on one side and the other side of the tire in the tire circumferential direction of the width direction groove 20, and the number of dimensions thereof is the communication sipe 21. It should be higher than the number of dimensions.

In the above embodiment, the circumferential grooves 12 to 14 are linear. However, the circumferential grooves 12 to 14 may be inclined, bent, or curved.
In the above embodiment, the lug groove 15 has a curved line extending from the lower right to the upper left and a curved line extending from the lower left to the upper right. However, the lug groove 15 may be linear, It may be inclined. Alternatively, it may be bent or curved.
In the above-described embodiment, the tread pattern tire 10 having the five circumferential grooves 12 to 15 has been described. However, the tread pattern of the tire 10 is not limited to this, and three circumferential grooves are provided. It may be a tread pattern. Further, it may be a tread pattern that is asymmetrical with respect to the tire equatorial plane CL.

The present invention includes at least three circumferential grooves formed on the surface of a tread so as to extend along the tire circumferential direction, lug grooves extending in a direction intersecting the circumferential groove, circumferential grooves and lug grooves. And a plurality of blocks partitioned by the tire, wherein the blocks extend in a direction intersecting the tire circumferential direction, one circumferential end of the circumferential groove defining one of the blocks in the circumferential direction outside the tire width direction Width direction groove that opens to the groove or tread grounding end and the other end terminates inside the block, and is formed on one side and the other side of the width direction groove in the tire circumferential direction on the surface of the block And at least one sipe extending in a direction intersecting the tire circumferential direction, and a communication sipe communicating with the end of the width direction groove and the circumferential groove or tread grounding end located on the end side. To
Thus, since the sipe is replaced with the width direction groove having an edge component larger than the sipe, the number of sipes can be reduced while securing the edge component. Moreover, since the collapse of the block can be reduced, the wear resistance performance of the block can be improved.
In addition, since one end of the width direction groove (specifically, the end portion on the outer side in the tire width direction) is opened, water entering the width direction groove can be effectively drained, and the other end (in detail) Since the end in the tire width direction is terminated in the block, the circumferential rigidity of the block can be ensured. The reason for providing the communication sipe is to prevent the block rigidity from becoming excessively large locally at the end portion of the widthwise groove and preventing the block from being sheared and deformed in the circumferential direction.
In addition, since the width direction groove | channel was provided between the sipe, the rigidity fall at the circumferential direction edge part side of a block can be suppressed.
As described above, according to the present invention, the edge component can be ensured without reducing the block rigidity, so that both the performance on snow and the wear resistance can be improved.

Further, the present invention is characterized in that the width direction groove is a width direction groove having one end opened to the tread grounding end and the other end terminated inside the block.
As described above, since the width direction groove is provided in the tire shoulder portion, the water that has entered the tire contact surface can be effectively drained to the outside in the tire width direction, and the portion of the shoulder land portion that has the most severe wear conditions. Since the terminal portion is provided on the side facing the outermost circumferential groove in the width direction, both drainage performance and wear resistance performance can be achieved.
In addition, since the groove depth on the end side of the width direction groove is formed so as to become shallower toward the end, it is possible to prevent a local decrease in block rigidity, so that the block rigidity in the tire width direction can be prevented. Unevenness can be interpolated, and uneven wear of the block can be suppressed.
Further, the present invention is characterized in that, among the plurality of sipes, the number of dimensions of the sipes formed on the tire circumferential direction end side of the block having the width direction groove is higher than the number of dimensions of the communicating sipes.
Thereby, since the rigidity of the circumferential direction edge part side of the block which has a width direction groove | channel can be ensured and block deformation | transformation can be suppressed, abrasion resistance performance can be improved.

Further, according to the present invention, in the block located at least on the outermost side in the tire width direction, the angle formed by the extending direction of the groove wall on the stepping end side of the block and the tire width direction is the kicking end side. It is characterized in that it is larger than the angle formed between the extending direction of the groove wall and the tire width direction.
Thereby, since the groove width of the lug groove which divides at least the shoulder block which is a block of the tire width direction outer side can be made wide as it goes to the tire width direction outer side, drainage performance can be improved.
At this time, it is preferable to reduce the groove wall angle by cutting the groove wall on the kicking-out end side with less influence while leaving the stepping end side that is the wall surface to which water is most exposed. Needless to say, when the groove wall on the kicking end side is cut, the amount of cutting on the outer side in the tire width direction is increased.

10 tires, 11 treads, 12 center main grooves, 13 outer main grooves,
14 shoulder groove, 15 lug groove, 16 center block,
17 2nd block, 18 shoulder block,
19, 19a to 19c sipe, 20 width direction groove, 21 communicating sipe,
CL tire equator, TG tread ground contact.

Claims

At least three circumferential grooves formed on the surface of the tread so as to extend along the tire circumferential direction, lug grooves extending in a direction intersecting the circumferential groove, the circumferential grooves and the lug grooves; A tire having a plurality of blocks partitioned by
The block is
One end extends in a direction intersecting the tire circumferential direction, one end opens in a circumferential groove on the outer side in the tire width direction among the circumferential grooves defining the block, or a tread grounding end, and the other end is inside the block. A widthwise groove that terminates;
At least one sipe extending in a direction intersecting the tire circumferential direction formed on one side and the other side of the tire circumferential direction of the width direction groove on the surface of the block;
A tire comprising: a sipe that communicates with a terminal end of the width direction groove and a circumferential groove or a tread grounding end located on the terminal end side.
The tire according to claim 1, wherein the width direction groove is a width direction groove having one end opened to a tread ground contact end and the other end terminating in the block.
The tire according to claim 1 or 2, wherein a groove depth on a terminal side of the width direction groove becomes shallower toward the terminal.
The dimension number of sipes formed on the tire circumferential direction end side of the block having the widthwise grooves among the plurality of sipes is higher than the dimension number of the communicating sipes. Item 4. The tire according to any one of Items 3.
Of the blocks, the block located at least on the outermost side in the tire width direction is such that the angle formed between the extending direction of the groove wall on the stepping end side of the block and the tire width direction is the groove wall on the kicking end side of the block. The tire according to any one of claims 1 to 4, wherein the tire is larger than an angle formed by an extending direction of the tire and a tire width direction.