JP2013180693A - Tire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tire of which the performances on snow can be further improved.SOLUTION: A tire includes a plurality of inclined grooves extending in a direction inclined with respect to a tire circumference direction, arranged in the tire circumference direction; and block-like land parts formed and segmented by the plurality of inclined grooves include sipes extending in a tread width direction. The inclined groove extends outwardly in a tread width direction from a center part in the tread width direction including the tire equator line. One groove wall surface in the inclined groove is formed into a straight or curved line, while the other groove wall surface of the inclined groove is formed into a wavy pattern by forming a plurality of angular parts protruding inside the inclined groove.

Description

  The present invention relates to a tire in which a plurality of inclined grooves inclined with respect to the tire circumferential direction are formed in the tire circumferential direction, and a sipe extending in the tread width direction is formed in a block-like land portion provided between the inclined grooves.

  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 improve performance on icy and snowy roads and wet roads. For example, a plurality of inclined grooves that are inclined with respect to the tire circumferential direction are formed from the central portion in the tread width direction toward the outer side in the tread width direction, and the land portion is formed by being partitioned into the inclined grooves. Tires are known (see Patent Document 1).

  In such a tire, a sipe is formed in the land portion, and a tapered portion is provided at an edge portion formed in the land portion by the inclined groove. In a tire having such a tapered portion, when running on a snowy road, a high-strength snow column is formed in the inclined groove by the tapered portion, so that the braking performance on the snowy road is improved by improving the snow column shear force. And performance on snow such as driving performance is secured.

JP 2010-184570 A (FIG. 1)

  However, in recent years, with the improvement in the performance of passenger cars, there has been a further increase in demand for improving the performance on snow.

  Therefore, the present invention has been made in view of such a situation, and an object thereof is to provide a tire capable of further improving the performance on snow.

  In the tire (pneumatic tire 1) according to the feature of the present invention, a plurality of inclined grooves (inclined grooves 100) extending in a direction inclined with respect to the tire circumferential direction are formed in the tire circumferential direction, and are partitioned by the plurality of inclined grooves. A sipe (sipe 50) extending in the tread width direction is formed in the block-like land portion (block-like land portion 40). The inclined groove extends from the center in the tread width direction including the tire equator line toward the outside in the tread width direction. One groove wall surface (groove wall surface 110) in the inclined groove is formed in a linear shape or a curved shape, and the other groove wall surface (groove wall surface 120) in the inclined groove has a plurality of corners protruding inside the inclined groove. By forming the portion (corner portion P), the gist is formed.

  According to the characteristics of the present invention, a tire capable of further improving the performance on snow can be provided.

FIG. 1 is a partial plan development view of a tread portion 2 of a pneumatic tire 1 according to a first embodiment of the present invention. FIG. 2 is a partially enlarged plan view of the tread portion 2 of the pneumatic tire 1 according to the first embodiment of the present invention. FIG. 3 is a partial plan view of a tread portion of a pneumatic tire 1A according to another 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.

[First Embodiment]
(1) Schematic Configuration of Pneumatic Tire FIG. 1 is a partial plan development view of the tread portion 2 of the pneumatic tire 1 according to the first embodiment. As shown in FIG. 1, a circumferential groove 20 and a circumferential groove 30 that extend linearly along the tire circumferential direction Tc are formed in the pneumatic tire 1. In addition, the circumferential groove | channel 20 and the circumferential groove | channel 30 may have the part extended in curvilinear form, if it extends in the tire circumferential direction Tc.

  The pneumatic tire 1 is a so-called winter tire that can withstand use during snowfall, and has a tread pattern in which a tire rotation direction Tr is specified when mounted on an automobile. The designation of the tire rotation direction Tr indicates that the tire rotation direction Tr is designated by marking an “arrow” indicating the tire rotation direction Tr on the tire side portion, for example. In addition, the winter tire here refers to a tire including a studless tire that places importance on performance on an icy snow road and an all-season tire that ensures a balanced performance on an icy snow road and a non-icy snow road. The pneumatic tire 1 may be filled with an inert gas such as nitrogen gas instead of air.

  Here, in FIG. 1, the contact range in the tread width direction Tw of the tread portion 2 is a range in the both ends TE of the tread width direction Tw of the contact range in a state where the pneumatic tire 1 is in contact with the road surface. The state where the tire is in contact with the road surface indicates, for example, a state where the tire is mounted on a normal rim and a normal internal pressure and a normal load are applied. The regular rim refers to a standard rim in an applicable size defined in the 2010 JAYMA (Japan Automobile Tire Association) YearBook 2010 edition. The normal internal pressure is the air pressure corresponding to the maximum load capacity of the JATMA Year Book 2010 version, and the normal load is the load corresponding to the maximum load capacity when the single wheel of the JATMA Year Book 2010 version is applied. . Outside Japan, the standards governing these are determined by industry standards that are valid in the region where the tire is produced or used. For example, in the United States, it is “The Year Book of The Tire and Rim Association Inc.”, and in Europe it is “The Standards Manual of the European Tire and Rim Technical Organization”.

  In addition, a plurality of block land portions 40 are provided between the circumferential groove 20 and the circumferential groove 30. That is, the block-like land portion 40 is provided in a region including the tire equator line CL. In the tread width direction Tw, the region where the block-shaped land portion 40 is formed includes the tire equator line CL and is preferably in the range of 60% or more and 70% or less in the both ends TE of the tread portion 2. .

  Further, a sipe 50 extending in the tread width direction Tw is formed in the block-shaped land portion 40. Here, the sipe has a groove width that can be closed when the block is grounded. Specifically, the sipe 50 has a groove width of 1.5 mm or less. However, the groove width of the sipe is not limited to this. For example, in a tire used for a large bus or truck such as a TBR tire, the sipe groove width may be 1.5 mm or more.

  The pneumatic tire 1 may be formed with a sipe (not shown). For example, the pneumatic tire 1 may be formed with a sipe extending in the tread width direction Tw and a sipe extending in the tire circumferential direction Tc. The sipe 50 may be a sipe extending linearly or a sipe extending zigzag. A linear sipe 60 extending along the tire circumferential direction Tc is formed at the position of the tire equator line CL. In the pneumatic tire 1, the sipe 60 may not be formed.

  In the tread portion 2, a plurality of inclined grooves 100 extending in a direction inclined with respect to the tire circumferential direction Tc are formed in the tire circumferential direction Tc. The block land portion 40 is formed by being partitioned into a plurality of inclined grooves 100 that are inclined with respect to the tire circumferential direction Tc.

  The inclined groove 100 extends from the central portion A0 in the tread width direction Tw, specifically, from the tire equator line CL toward the tread width direction Tw. The central portion A0 in the tread width direction Tw is the tread ground contact width including the tire equator line CL in a state where a normal load is applied to the pneumatic tire 1 set to the normal internal pressure defined in the above-described standard. This means a part or all of the 60% area. In the present embodiment, a sipe 60 extending along the tire equator line CL is formed in the central portion A0.

  By forming the inclined groove 100 described above in the tread portion 2, one groove wall surface 110 is formed in the block-like land portion 40 adjacent to one of the inclined grooves 100, and the block-like land adjacent to the other of the inclined grooves 100. The other groove wall surface 120 is formed in the portion 40. The detailed configuration of the inclined groove 100 will be described later.

(2) Structure of inclined groove Next, the structure of the inclined groove 100 will be described in detail. FIG. 2 is a partially enlarged plan view of the tread of the pneumatic tire 1. As shown in FIG. 2, one groove wall surface 110 in the inclined groove 100 is formed in a linear shape or a curved shape in the tread surface view. In the present embodiment, one groove wall surface 110 in the inclined groove 100 extends linearly when viewed from the tread surface. In addition, the other groove wall surface 120 in the inclined groove 100 is formed in a wave shape by forming a plurality of corner portions P protruding inside the inclined groove 100.

  Further, the other groove wall surface 120 extends in a direction Z1 that becomes the first angle θ1 with respect to the tread width direction Tw and in a direction Z2 that becomes the second angle θ2 with respect to the tread width direction Tw. The second groove wall surface 120b is formed by being alternately formed. The corner P is formed between the first groove wall surface 120a and the second groove wall surface 120b.

  By such an inclined groove 100, a linear kick-out end is formed on one groove wall surface 110 side on the ground contact surface of the block-shaped land portion 40, and a wave shape (zigzag shape) is formed on the other groove wall surface 120 side. Is formed.

  In the present embodiment, the first angle θ1 formed between the extending direction Z1 of the first groove wall surface 120a and the tread width direction Tw is the first angle θ1 formed between the extending direction Z2 of the second groove wall surface 120b and the tread width direction Tw. It is smaller than the two angle θ2. Specifically, the first angle θ1 is preferably “a range of −10 ° or more and + 10 ° or less” with respect to the tread width direction Tw, and the second angle θ2 is “within the tread width direction Tw” A range of 40 ° or more and 60 ° or less is preferable. That is, the stepped end formed on the groove wall surface 120 side of the block-shaped land portion 40 has a low-angle portion having a first angle θ1 with respect to the tread width direction Tw and a second angle θ2 with respect to the tread width direction Tw. And a high-angle portion. The first angle θ1 is more preferably “0 °”. That is, the extending direction Z1 of the first groove wall surface 120a is more preferably parallel to the tread width direction Tw.

  In addition, the inclined groove 100 includes a wide portion 100w in which the groove width of the inclined groove 100 is a predetermined width, and a narrow portion 100n in which the groove width of the inclined groove 100 is narrower than that of the wide portion 100w. The other groove wall surface 120 is formed. Specifically, the wide portion 100w and the narrow portion 100n are alternately repeated along the extending direction of the inclined groove 100.

  The inclined grooves 100 are respectively formed in one region and the other region in the tread width direction Tw with reference to the tire equator line CL. The inclined groove 100 has a substantially symmetric (line symmetric) shape in the one region and the other region.

  In the inclined groove 100, in the central portion A0 in the tread width direction Tw including the tire equator line CL, the inclined groove 100 formed in the one region and the block land portion 40 provided in the other region face each other. . Conversely, the inclined groove 100 formed in the other region and the block-shaped land portion 40 provided in the one region face each other. That is, the arrangement positions of the block-shaped land portion 40 and the inclined groove 100 are shifted in the tire circumferential direction Tc between the one region and the other region.

  Further, the end 100X of the inclined groove 100 outside the tread width direction Tw communicates with the circumferential groove 20 (circumferential groove 30). The inclined groove 100 extends to the circumferential groove 20 (circumferential groove 30) without intersecting with other than the sipe 50. In addition, the end part (not shown) inside the tread width direction Tw of the inclined groove 100 may communicate with the sipe 60 extending to the tire equator line CL.

(3) Action / Effect In the pneumatic tire 1 described above, the inclined groove 100 extends from the central portion A0 in the tread width direction Tw including the tire equator line CL toward the outside of the tread width direction Tw.

  Further, one groove wall surface 110 in the inclined groove 100 is formed in a straight line shape in the tread surface view. On the other hand, the other groove wall surface 120 in the inclined groove 100 is formed in a wave shape by forming a plurality of corner portions P protruding inside the inclined groove 100 in the tread surface view.

  By forming the inclined groove 100 in this way, the inclined groove 100 includes a wide portion 100w where the groove width of the inclined groove 100 is a predetermined width, and a narrow portion where the groove width of the inclined groove 100 is narrower than the wide portion 100w. 100n are formed. Specifically, the wide portion 100w and the narrow portion 100n of the inclined groove 100 are alternately repeated from the center portion A0 in the tread width direction Tw toward the outside of the tread width direction Tw.

  For this reason, the snow that has entered the inclined groove 100 when traveling on a snowy road is restricted from escape, and as a result, the snow column shear force increases. Therefore, according to the pneumatic tire 1, performance on snow such as driving force and braking force on a snowy road is improved. That is, according to the pneumatic tire 1, it is possible to further improve the performance on snow.

  Moreover, in the pneumatic tire 1, the groove wall surface 120 of the inclined groove 100 formed in a wave shape is constituted by a first groove wall surface 120a and a second groove wall surface 120b. Further, the first angle θ1 formed by the extending direction Z1 of the first groove wall surface 120a and the tread width direction Tw is larger than the second angle θ2 formed by the extending direction Z2 of the second groove wall surface 120b and the tread width direction Tw. small. Specifically, the stepped end formed on the groove wall surface 120 side of the block-shaped land portion 40 includes a low-angle portion having a first angle θ1 with respect to the tread width direction Tw and a second angle with respect to the tread width direction Tw. A high-angle portion having an angle θ2 is formed.

  According to the pneumatic tire 1, the edge effect of the stepped end can be enhanced by the low-angle portion formed at the stepped end, so that the driving force on the snowy road, the icy road, and the wet road can be increased. become. That is, according to the pneumatic tire 1, it is possible to improve the performance on snow, the performance on ice, and the wet performance.

  Further, in the pneumatic tire 1, the narrow portion 100n where the groove width of the inclined groove 100 is narrow is located at the outer end portion of the low-angle portion in the tread width direction Tw. Further, the snow entering the inclined groove 100 can be increased by the low angle portion formed at the stepping end. Here, it is preferable to form a thick and long snow column in the inclined groove 100. Thus, in order to form a thick and long snow column, it is preferable to have a portion with a narrow groove width (for example, a portion with a groove width of about 5 mm). According to the pneumatic tire 1 according to the present embodiment, the snow taken in by the low-angle portion formed at the stepping end is retained in the narrow portion 100n having a narrow groove width, so that a thick and long snow column is obtained. Since it can be formed, the snow column shear force can be increased efficiently and the performance on snow can be improved.

  Further, the inclined groove 100 extends from the center portion A0 in the tread width direction Tw including the tire equator line CL toward the outside of the tread width direction Tw. According to the pneumatic tire 1, water between the block-like land portion 40 and the road surface is gradually pushed out along the inclined groove 100 to the outside in the tread width direction Tw when the tire rotates. It becomes possible to secure.

  Furthermore, since the inclined groove 100 extends toward the outer side of the tread width direction Tw and communicates with the circumferential grooves 20 and 30, rainwater that has entered the inclined groove 100 can be efficiently drained.

  That is, according to the pneumatic tire 1, it is possible to achieve both high performance on snow and high wet performance.

  Moreover, according to this pneumatic tire 1, the arrangement positions of the block-like land portion 40 and the inclined groove 100 are shifted in the tire circumferential direction Tc in one region and the other region with respect to the tire equator line CL. . For this reason, when the low angle portion having the first angle θ1 with respect to the tread width direction Tw contacts the road surface, the timing at which the low angle portion formed in one region with respect to the tire equator line CL is grounded, It is possible to disperse the timing at which the low-angle portion formed in the region of the ground contacts the ground. As a result, vibrations in the pneumatic tire 1 are dispersed, and tire noise can be reduced.

  For example, if the extending direction of the inclined groove 100 is around 45 ° with respect to the tire circumferential direction Tc, it can also contribute to an improvement in handling performance.

[Other Embodiments]
Although the contents of the present invention have been disclosed through the embodiments of the present invention as described above, it should not be understood that the descriptions and drawings constituting a part of this disclosure limit the present invention. From this disclosure, various alternative embodiments, examples, and operational techniques will be apparent to those skilled in the art.

  For example, in the pneumatic tire 1 according to the first embodiment described above, the groove wall surface 120 of the inclined groove 100 formed in a wave shape is formed on the stepping end side of the block-shaped land portion 40, but is shown in FIG. Like the pneumatic tire 1A, it may be formed on the kicking end side. That is, the wavy groove wall surface 120 may be formed on the kicking end side of the block-shaped land portion 40, and the linear groove wall surface 110 may be formed on the stepping-end side of the block-shaped land portion 40.

  Even in such a pneumatic tire 1A, it is possible to increase the snow column shear force caused by the snow that has entered the inclined groove 100 when traveling on a snowy road, and the performance on snow is improved. Further, according to the pneumatic tire 1A, the edge effect of the kicking end can be enhanced by the low-angle portion formed at the kicking end, so that the braking performance by the edge effect can be enhanced.

  Further, in the pneumatic tire 1 according to the above-described embodiment, the arrangement positions of the block-like land portion 40 and the inclined groove 100 are in the tire circumferential direction Tc in one region with respect to the tire equator line CL and the other region. However, such an arrangement is not necessarily essential, and the arrangement positions of the block-like land portion 40 and the inclined groove 100 may coincide with each other in the tire circumferential direction Tc.

  In the embodiment described above, the central portion A0 in the tread width direction Tw is a tread including the tire equator line CL in a state where a normal load is applied to the pneumatic tire 1 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 an automobile with a large camber angle, the area of 60% of the tread contact width including the tire equator line CL is meant. It may also mean outside.

  In the above-described embodiment, the case where the sipe 60 extending along the tire circumferential direction Tc is formed on the tire equator line CL in the central portion A0 has been described as an example, but the circumferential groove is formed. It may be.

  In the embodiment described above, one groove wall surface 110 in the inclined groove 100 has been described as an example in which the groove wall surface 110 is formed in a straight line shape in the tread surface view, but may be formed in a curved line shape (arc shape). Good.

  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.

DESCRIPTION OF SYMBOLS 1,1A ... Pneumatic tire, CL ... Tire equator line, P ... Corner | angular part, Tc ... Tire circumferential direction, Tr ... Tire rotating direction, Tw ... Tread width direction, 2 ... Tread part, 20, 30 ... Circumferential groove | channel, 40 ... Block-shaped land portion, 50 ... Sipe, 60 ... Sipe, 100 ... Inclined groove, 100X ... End portion, 100n ... Narrow portion, 100w ... Wide portion, 110 ... Groove wall surface, 120 ... Groove wall surface, 120a ... First Groove wall surface, 120b ... second groove wall surface

Claims (4)

A plurality of inclined grooves extending in a direction inclined with respect to the tire circumferential direction are formed in the tire circumferential direction, and a sipe extending in the tread width direction is formed in a block-shaped land portion formed by being partitioned by the plurality of inclined grooves. Tire,
The inclined groove extends from the center in the tread width direction including the tire equator line toward the outside in the tread width direction,
One groove wall surface in the inclined groove is formed in a linear shape or a curved shape,
The other groove wall surface in the inclined groove is formed in a wave shape by forming a plurality of corners protruding inside the inclined groove. In the inclined groove,
A wide portion in which the groove width of the inclined groove is a predetermined width and a narrow portion in which the groove width of the inclined groove is narrower than the wide portion are formed by the one groove wall surface and the other groove wall surface. The tire according to claim 1. The other groove wall surface is
The first groove wall surface that extends in the direction that forms the first angle with respect to the tread width direction and the second groove wall surface that extends in the direction that forms the second angle with respect to the tread width direction are formed alternately. And
The tire according to claim 1 or 2, wherein the first angle is smaller than the second angle. A circumferential groove extending linearly along the tire circumferential direction is formed,
The tire according to any one of claims 1 to 3, wherein an end of the inclined groove on the outer side in the tread width direction communicates with the circumferential groove.