JP5876866B2 - Winter tires - Google Patents

Description

  The present invention relates to a winter tire having excellent snow performance.

  In Patent Document 1 below, in order to improve the performance on snow, the tread portion is provided with a plurality of vertical grooves extending linearly and continuously in the tire circumferential direction, and a horizontal groove crossing the land portion between the vertical grooves. Winter tires have been proposed.

  By the way, on the snowy road surface, there is a tendency that protrusions extending along the running direction are formed by the comb-shaped snow blades of the road surface maintenance vehicle. When running on such a snowy road surface with the above-mentioned winter tire, there is a problem that a wandering phenomenon that the vertical groove of the tire engages with the protrusion and the vehicle is guided along the protrusion easily occurs.

JP 2006-298202 A

  The present invention has been devised in view of the above problems, and has as its main object to provide a winter tire capable of improving the performance on snow without impairing the wandering resistance.

The present invention relates to a winter tire having a tread portion, and the tread portion terminates obliquely from one tread end toward the tire equator side and beyond the tire equator without reaching the other tread end. A plurality of first inclined main grooves that extend between the first inclined main grooves and extend obliquely in the same direction as the first inclined main grooves from the one tread end toward the tire equator side. A first inclined sub-groove that terminates without crossing the equator, and extends obliquely from the other tread end toward the tire equator side in an opposite direction to the first inclined main groove and beyond the tire equator to the one tread end. A plurality of second inclined main grooves that end without being inclined, and are inclined between the second inclined main grooves and in the same direction as the second inclined main grooves from the other tread end toward the tire equator side. Nobikatsu tire A plurality of second inclined sub-grooves that terminate without crossing the road and each first land portion divided between the first inclined main grooves and inclined in the same direction as the first inclined main grooves And a plurality of second vertical grooves that divide each second land portion divided between the second inclined main grooves and are inclined in the same direction as the second inclined main grooves. provided al is, the first inclined main groove has a first inner end terminating communication with said second inclined main groove, the second inclined main grooves, in communication with the first inclined main groove It has a second inner end that terminates, and the first inclined main groove and the second inclined main groove are provided alternately in the tire circumferential direction .

  In the winter tire according to the present invention, it is preferable that the first inclined main groove and the second inclined main groove have an arc shape in which an inclination angle with respect to the tire axial direction gradually decreases toward the tread end side.

  In the winter tire of the present invention, it is preferable that the first vertical grooves adjacent to each other through the first inclined main groove communicate with the first inclined main groove at different positions in the tire axial direction.

  In the winter tire according to the present invention, it is preferable that the first vertical groove includes an inner first vertical groove and an outer first vertical groove disposed on the outer side in the tire axial direction of the inner first vertical groove. .

  In the winter tire of the present invention, it is preferable that the first inclined sub-groove terminates beyond the inner first longitudinal groove toward the tire equator side.

  In the winter tire of the present invention, it is preferable that the second vertical grooves adjacent to each other through the second inclined main groove communicate with the second inclined main groove at different positions in the tire axial direction.

  In the winter tire of the present invention, it is preferable that the second vertical groove includes an inner second vertical groove and an outer second vertical groove disposed on the outer side in the tire axial direction of the inner second vertical groove. .

  In the winter tire according to the present invention, it is preferable that the second inclined sub-groove terminates beyond the inner second longitudinal groove toward the tire equator side.

  The winter tire of the present invention has a first inclined main groove having a length exceeding the tire equator from one tread end and a second inclined main groove having a length exceeding the tire equator from the other tread end in the tread portion. Each is provided. Between the first inclined main grooves, a first inclined sub groove having a length that does not reach the tire equator from one tread end is provided. Between the second inclined main grooves, a second inclined sub groove having a length that does not reach the tire equator from the other tread end is provided. These inclined main grooves and inclined subgrooves can improve the wandering resistance performance by breaking the protrusions along the running direction of the snow road surface.

  In addition, the inclined main groove and the inclined sub-groove can generate a large snow column shearing force on the snowy road and exhibit high traction performance on the snow. Moreover, since these inclined main grooves and inclined sub-grooves also have components in the tire circumferential direction, a high lateral grip can be provided even during turning.

  Furthermore, the winter tire of the present invention includes a plurality of first vertical grooves that divide each first land portion divided between the first inclined main grooves and are inclined in the same direction as the first inclined main grooves. A plurality of second vertical grooves that divide each second land portion divided between the second inclined main grooves and are inclined in the same direction as the second inclined main grooves are provided. These vertical grooves can supplement the tire circumferential direction component and further enhance the lateral grip. In addition, since these vertical grooves divide the first land portion and the second land portion, it is possible to promote deformation of the land portion at the time of ground contact and prevent snow clogging of the inclined main groove and the inclined sub groove. .

It is an expanded view of the tread part of the pneumatic tire of this embodiment. It is AA sectional drawing of FIG. It is an enlarged view of the 1st land part of FIG.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 shows a tread portion 2 of a winter tire (hereinafter sometimes simply referred to as “tire”) 1 of the present embodiment. The tire 1 of this embodiment is suitably used as a winter tire for passenger cars, for example.

  As shown in FIG. 1, the tread portion 2 is provided with a plurality of inclined main grooves 10, inclined sub-grooves 20, and longitudinal grooves 30.

  The inclined main groove 10 extends obliquely from the tread end Te toward the tire equator C and terminates beyond the tire equator C.

  The tread end Te is a contact position on the outermost side in the tire axial direction when a normal load is applied to the tire 1 in a normal state and the tire 1 contacts the plane with a camber angle of 0 °. The normal state is a state in which the tire is assembled on the normal rim and is filled with the normal internal pressure, and further, there is no load. In the present specification, unless otherwise specified, the dimensions and the like of each part of the tire are values measured in a normal state.

  The “regular rim” is a rim determined for each tire in a standard system including a standard on which the tire is based. For example, “Standard Rim” for JATMA, “Design Rim” for TRA, ETRTO Then "Measuring Rim".

  The “regular internal pressure” is an air pressure determined by each standard for each tire in the standard system including the standard on which the tire is based. The maximum value described in “AT VARIOUS COLD INFLATION PRESSURES”, “INFLATION PRESSURE” in the case of ETRTO.

  The “regular load” is a load determined by each standard for each tire in the standard system including the standard on which the tire is based. “JATMA” indicates “maximum load capacity”, and TRA indicates “TIRE LOAD”. The maximum value described in “LIMITS AT VARIOUS COLD INFLATION PRESSURES”, “LOAD CAPACITY” in the case of ETRTO.

  As shown in FIG. 1, the inclined main groove 10 includes a first inclined main groove 11 and a second inclined main groove 12.

  The first inclined main groove 11 extends from one tread end Te1 toward the tire equator C side. The first inclined main groove 11 ends beyond the tire equator C and does not reach the other tread end Te2.

  The second inclined main groove 12 extends in the direction opposite to the first inclined main groove 11 from the other tread end Te2 toward the tire equator C side. The second inclined main groove 12 ends beyond the tire equator C and does not reach one tread end Te1.

  The inclined sub-groove 20 is provided between the inclined main grooves 10 and 10 adjacent in the tire circumferential direction. The inclined sub-groove 20 extends obliquely from the tread end Te toward the tire equator C and terminates without exceeding the tire equator C.

  As shown in FIG. 1, the inclined sub-groove 20 includes a first inclined sub-groove 21 and a second inclined sub-groove 22.

  The first inclined sub-groove 21 is provided between the first inclined main grooves 11 and 11 that are adjacent in the tire circumferential direction. The first inclined sub-groove 21 extends obliquely in the same direction as the first inclined main groove 11 from the one tread end Te1 toward the tire equator C side.

  The second inclined sub-groove 22 is provided between the second inclined main grooves 12 and 12 adjacent in the tire circumferential direction. The second inclined sub-groove 22 extends obliquely in the same direction as the second inclined main groove 12 from the other tread end Te2 toward the tire equator C.

  The inclined main groove 10 and the inclined sub-groove 20 can improve the wandering resistance performance by breaking the protrusion along the running direction of the snow road surface. Further, the inclined main groove 10 and the inclined sub-groove 20 can generate a large snow column shearing force on a snowy road and exhibit high traction performance on snow. In addition, since the inclined main groove 10 and the inclined sub-groove 20 also have components in the tire circumferential direction, a high lateral grip can be provided even during turning.

  In order to further exert the above-described effects, the groove width W1 of the inclined main groove 10 and the groove width W2 of the inclined sub groove 20 are preferably 3.0 to 8.5% of the tread ground contact width TW, for example. The tread contact width TW is a distance in the tire axial direction between one and the other tread ends Te1 and Te2 of the tire 1 in the normal state.

  FIG. 2 is a cross-sectional view taken along the line AA in FIG. As shown in FIG. 2, the groove depth d1 of the inclined main groove 10 and the groove depth d2 of the inclined sub-groove 20 are preferably 3.0 to 10.0 mm, for example.

  The first inclined main groove 11 of the present embodiment desirably has a first inner end 11i that terminates in communication with the second inclined main groove 12, for example. The second inclined main groove 12 of this embodiment desirably has a second inner end 12i that terminates in communication with the first inclined main groove 11, for example. Thereby, the projection on the surface of the snow road is effectively broken at the connecting portion 13 between the first inclined main groove 11 and the second inclined main groove 12, and a large snow column shear force is obtained.

  The first inclined main grooves 11 and the second inclined main grooves 12 are desirably provided alternately in the tire circumferential direction, for example. Thereby, the uneven wear of the tread portion 2 is effectively suppressed.

  It is desirable that the inclined main groove 10 of the present embodiment has an arc shape in which the inclination angle θ1 with respect to the tire axial direction gradually decreases toward the tread end Te side. Such an inclined main groove 10 relaxes the rigidity in the tire circumferential direction of the land portion in the vicinity of the tread end Te while maintaining the rigidity in the tire circumferential direction in the vicinity of the tire equator C to which a large contact pressure acts. Accordingly, the wandering resistance is improved while maintaining the steering stability.

  The inclination angle θ1 of the inclined main groove 10 is preferably 35 ° or more, more preferably 40 ° or more, preferably 50 ° or less, more preferably 45 ° or less. Such an inclined main groove 10 balances the steering stability performance and the wandering performance with a good balance.

  From the same viewpoint, the inclination angle θ2 of the inclined sub-groove 20 is preferably 20 ° or more, more preferably 25 ° or more, preferably 35 ° or less, more preferably 30 ° or less.

  The inclined main groove 10 and the inclined sub-groove 20 are desirably substantially parallel to the tire axial direction at the tread end Te. As a result, when running on a snowy road, the protrusions on the snowy road surface are effectively broken and the wandering phenomenon is suppressed.

  The vertical groove 30 divides the land portion 5 divided between the inclined main grooves 10 and 10 and extends in the tire circumferential direction. The vertical groove 30 is inclined in the same direction as the inclined main groove 10 adjacent in the tire circumferential direction.

  As shown in FIG. 3, the longitudinal groove 30 includes a first longitudinal groove 31 and a second longitudinal groove 32.

  The first vertical groove 31 divides each first land portion 5 </ b> A divided between the first inclined main grooves 11 and 11. The first vertical groove 31 is inclined in the same direction as the first inclined main groove 11.

  The second vertical groove 32 divides each second land portion 5 </ b> B divided between the second inclined main grooves 12, 12. The second vertical groove 32 is inclined in the same direction as the second inclined main groove 12.

  These longitudinal grooves 30 can supplement the tire circumferential direction component and further enhance the lateral grip. In addition, since these vertical grooves 30 divide the first land portion 5A and the second land portion 5B, at the time of ground contact, the deformation of the land portion is promoted, and snow clogging of the inclined main groove 10 and the inclined sub-groove 20 is prevented. Can be prevented.

  In order to obtain a large snow column shear force while suppressing snow clogging, the groove width W3 of the longitudinal groove 30 is preferably 2.5 to 8.0% of the tread ground contact width TW, for example. The groove depth d3 (shown in FIG. 2) of the vertical groove 30 is preferably, for example, 3.0 to 10.0 mm.

  As shown in FIG. 1, the tread portion 2 of the present embodiment is not provided with a main groove extending continuously in the tire circumferential direction over the circumference of the tire. The tire 1 according to this embodiment exhibits excellent wandering resistance performance without being guided by protrusions along the running direction of the snow road surface.

  In the present embodiment, the longitudinal grooves 30 adjacent in the tire circumferential direction are provided such that at least ends in the tire circumferential direction are displaced from each other in the tire axial direction.

  Specifically, the first vertical grooves 31 adjacent to each other via the first inclined main groove 11 communicate with the first inclined main groove 11 at different positions in the tire axial direction, for example. The second vertical grooves 32 adjacent via the second inclined main groove 12 communicate with the second inclined main groove 12 at different positions in the tire axial direction, for example.

  The first vertical groove 31 provided in the first land portion 5 </ b> A includes an inner first vertical groove 35 and an outer first vertical groove 36.

  The inner first vertical groove 35 is disposed on the tire equator C side. The inner first vertical groove 35 has one end communicating with the first inclined main groove 11 and the other end communicating with the second inclined main groove 12 adjacent in the tire axial direction.

  The outer first vertical groove 36 is disposed on the outer side in the tire axial direction of the inner first vertical groove 35. The outer first vertical groove 36 communicates between the first inclined main grooves 11 and 11 adjacent in the tire circumferential direction.

  The second vertical groove 32 includes an inner second vertical groove 37 and an outer second vertical groove 38.

  The inner second vertical groove 37 is disposed on the tire equator C side. The inner second vertical groove 37 has one end communicating with the second inclined main groove 12 and the other end communicating with the first inclined main groove 11 adjacent in the tire axial direction.

  The outer second vertical groove 38 is disposed on the outer side in the tire axial direction of the inner second vertical groove 37. The outer second vertical groove 38 communicates between the second inclined main grooves 12 and 12 adjacent in the tire circumferential direction.

  In the tire 1 in which the first vertical groove 31 and the second vertical groove 32 are arranged, even if the protrusion extending along the traveling direction on the road surface and the vertical groove 30 are engaged when traveling on a snowy road, Before being guided along the protrusion, the protrusion is broken by the inclined main groove 10 or the inclined sub-groove 20. Therefore, the wandering phenomenon is effectively suppressed.

  FIG. 3 shows an enlarged view of the first land portion 5A. As shown in FIG. 3, the inclination angle θ3 of the inner first vertical groove 35 with respect to the tire circumferential direction and the inclination angle θ4 of the outer first vertical groove 36 with respect to the tire circumferential direction are preferably 5 ° or more, more preferably It is 10 ° or more, preferably 20 ° or less, more preferably 15 ° or less. The inner first vertical groove 35 and the outer first vertical groove 36 provide a high lateral grip and effectively discharge the snow that has entered the groove when traveling on snow.

  The intersection P1 between the inner first vertical groove 35 and the first inclined main groove 11 is located on the outer side in the tire axial direction than the intersection P2 between the first inclined main groove 11 and the second inclined main groove 12. desirable. The distance L1 between the intersection point P1 and the intersection point P2 is preferably 15 mm or more, more preferably 18 mm or more, preferably 25 mm or less, more preferably 22 mm or less. Thereby, a large snow column is formed in the groove while the wandering phenomenon is suppressed, and the performance on snow is improved.

  The inner first vertical groove 35 intersects the first inclined sub groove 21. Accordingly, the first inclined sub-groove 21 terminates beyond the inner first vertical groove 35 toward the tire equator C side. The inner first vertical groove 35 includes a first portion 35 </ b> A and a second portion 35 </ b> B divided by the first inclined sub-groove 21.

  The first portion 35 </ b> A of the inner first vertical groove 35 communicates between the first inclined main groove 11 and the first inclined sub-groove 21. The second portion 35 </ b> B of the inner first vertical groove 35 communicates between the second inclined main groove 12 and the first inclined sub-groove 21.

  In the first inner longitudinal groove 35 of the present embodiment, the first portion 35A and the second portion 35B are smoothly continuous. Such an inner first vertical groove 35 forms a large snow column in the groove and effectively improves the performance on snow.

  For example, the first portion 35A and the second portion 35B of the inner first vertical groove 35 may be displaced from each other in the tire axial direction. In this case, the intersection P3 between the first portion 35A of the inner first vertical groove 35 and the first inclined sub-groove 21 and the intersection P4 between the second portion 35B of the inner first vertical groove 35 and the first inclined sub-groove 21 The distance L2 (not shown) is preferably 5 mm or more, more preferably 8 mm or more, preferably 15 mm or less, more preferably 12 mm or less. Such inner first vertical groove 35 further enhances the wandering resistance.

  An intersection P5 between the outer first vertical groove 36 and the first inclined main groove 11 and an intersection P6 between the outer first vertical groove 36 and the first inclined main groove 11 that are adjacent in the tire circumferential direction are mutually in the tire axial direction. It is desirable that the position is shifted. The distance L3 between the intersection point P5 and the intersection point P6 is preferably 20 mm or more, more preferably 23 mm or more, preferably 30 mm or less, more preferably 27 mm or less. Thereby, a large snow column is formed in the groove while the wandering phenomenon is suppressed, and the performance on snow is improved.

  The outer first vertical groove 36 intersects with the first inclined sub-groove 21, for example. As a result, the outer first vertical groove 36 includes a first portion 36A and a second portion 36B which are separated by the first inclined sub-groove 21.

  It is desirable that the first portion 36A and the second portion 36B of the outer first vertical groove 36 are displaced from each other in the tire axial direction. The distance L4 between the intersection P7 of the first portion 36A of the outer first vertical groove 36 and the first inclined sub-groove 21 and the intersection P8 of the second portion 36B of the outer first vertical groove 36 and the first inclined sub-groove 21. Is preferably 10 mm or more, more preferably 13 mm or more, preferably 20 mm or less, more preferably 17 mm or less. As a result, a large snow column is formed at the intersection between the outer first vertical groove 36 and the first inclined sub-groove 21, and excellent on-snow performance is exhibited.

  As shown in FIG. 1, the inner second vertical groove 37 and the outer second vertical groove 38 are substantially inwardly centered around the tire equator C with respect to the inner first vertical groove 35 and the outer first vertical groove 36. The first vertical groove 35 and the outer first vertical groove 36 have a line-symmetric shape. Accordingly, the above-described configurations of the inner first vertical groove 35 and the outer first vertical groove 36 are also provided in the inner second vertical groove 37 and the outer second vertical groove 38. The inner second vertical groove 37 and the outer second vertical groove 38, and the inner first vertical groove 35 and the outer first vertical groove 36 are spaced apart from each other in the tire circumferential direction with a half-pitch phase difference. .

  A plurality of center blocks 40, middle blocks 50, and shoulder blocks 60 are provided in the tread portion 2 in the tire circumferential direction.

  The center block 40 is divided by the first inclined main groove 11, the second inclined main groove 12, and the inner first vertical groove 35 or the inner second vertical groove 37. The center block 40 includes a substantially triangular tread surface, for example.

  The middle block 50 includes a first middle block 51 and a second middle block 52.

  The first middle block 51 is arranged in the first land portion 5 </ b> A and is divided by a first inclined main groove 11, a first inclined sub-groove 21, an inner first vertical groove 35, and an outer first vertical groove 36. . The second middle block 52 is disposed in the second land portion 5B, and is divided by the second inclined main groove 12, the second inclined sub-groove 22, the inner second vertical groove 37, and the outer second vertical groove 38. . Each of these middle blocks 50 includes, for example, a substantially parallelogram-shaped tread.

  The shoulder block 60 includes a first shoulder block 61 and a second shoulder block 62.

  The first shoulder block 61 is disposed in the first land portion 5 </ b> A and is divided by the first inclined main groove 11, the first inclined sub-groove 21, and the outer first vertical groove 36. The second shoulder block 62 is disposed in the second land portion 5 </ b> B and is divided by the second inclined main groove 12, the second inclined sub-groove 22, and the outer second vertical groove 38. Each of these shoulder blocks 60 has, for example, a substantially rectangular tread.

  Each shoulder block 60 preferably has, for example, a zigzag edge 65 extending in a zigzag shape in the tire axial direction. The zigzag edge 65 has, for example, a plurality of small protrusions 66 that are corners in the tire circumferential direction. The zigzag edge 65 of the present embodiment has, for example, 4 to 7 small protrusions 66. Such a zigzag edge 65 effectively bites into the road surface and exhibits excellent wandering resistance.

  Each block of the present embodiment is provided with a plurality of sipes 70 extending in the tire axial direction. Such a sipe 70 exhibits an excellent edge effect and effectively enhances the performance on ice. In this specification, “sipe” means a groove having a width of less than 1.0 mm.

  The shoulder block 60 is preferably provided with, for example, a semi-open sipe 71 having one end 71a communicating with each groove and the other end 71b terminating in the block. As a result, the rigidity of the shoulder block 60 is maintained, and the steering stability is improved.

  The tire 1 of the present embodiment is desirably a stud tire in which a plurality of stud pins 73 are provided on a block, for example. Such a stud pin 73 effectively enhances the running performance especially on an icy road.

  As shown in FIG. 1, as the winter tire of this embodiment, the land ratio Lr of the tread portion 2 is preferably 55% or more, more preferably 60% or more, preferably 70% or less, more preferably. 65% or less. Thereby, steering stability and performance on snow are compatible. In the present specification, the “land ratio” is a ratio Sb / Sa of the actual total ground contact area Sb to the total area Sa of the virtual ground contact surface where all the grooves and sipes are filled between the tread ends Te and Te. .

  The tread portion 2 is preferably formed of, for example, a tread rubber having a JISA hardness of 45 to 65 °. Such a tread rubber maintains flexibility and exhibits excellent performance on snow even on snow with a low road surface temperature. In this specification, JISA hardness means the hardness of rubber | gum by the durometer type A measured in the environment of 23 degreeC based on JIS-K6253.

  As described above, the winter tire of the present invention has been described in detail, but it is needless to say that the present invention is not limited to the above-described specific embodiment and can be implemented in various forms.

A winter tire for a passenger car of size 205 / 60R16 having the basic pattern of FIG. As Comparative Example 1, a tire having only a main groove extending continuously over one circumference of the tire and a lateral groove extending in the tire axial direction was manufactured. Each test tire was tested for snow performance and anti-wandering performance. The common specifications and test methods for each test tire are as follows.
Wearing rim: 16 x 6.5
Tire internal pressure: front wheel 240 kPa, rear wheel 220 kPa
Test vehicle: 2000cc displacement, front-wheel drive vehicle Tire mounting position: all wheels

<Snow performance>
The driving performance on the snow of the test vehicle equipped with each test tire was evaluated by the driver's sensuality. A result is a score which sets comparative example 1 to 100, and shows that performance on snow is excellent, so that a numerical value is large.

<Wandering resistance>
A test vehicle equipped with each test tire ran on an icy and snowy road surface with protrusions extending in the running direction. The behavior of the test vehicle, such as wobbling, was evaluated by the driver's sensuality. A result is a score which sets the comparative example 1 to 100, and shows that it is excellent in wandering-proof performance, so that a numerical value is large.
The test results are shown in Table 1.

  As is clear from Table 1, it was confirmed that the winter tires of the examples improved the performance on snow without impairing the wandering resistance.

DESCRIPTION OF SYMBOLS 1 Winter tire 2 Tread part 5A 1st land part 5B 2nd land part 11 1st inclination main groove 12 2nd inclination main groove 21 1st inclination subgroove 22 2nd inclination subgroove 31 1st vertical groove
32 Second vertical groove Te1 One tread end Te2 The other tread end

Claims (8)

A winter tire having a tread portion, wherein the tread portion has
A plurality of first inclined main grooves extending obliquely from one tread end toward the tire equator side and terminating without exceeding the tire equator and reaching the other tread end;
A first inclined sub that is provided between each of the first inclined main grooves and extends obliquely in the same direction as the first inclined main groove from the one tread end toward the tire equator side and does not cross the tire equator. Groove,
A plurality of second inclined main grooves extending obliquely in the opposite direction to the first inclined main groove from the other tread end toward the tire equator side and terminating beyond the tire equator and not reaching the one tread end;
A second inclined sub-portion provided between the second inclined main grooves and extending diagonally in the same direction as the second inclined main groove from the other tread end toward the tire equator side and without exceeding the tire equator. Groove,
A plurality of first vertical grooves that divide each first land portion divided between the first inclined main grooves and are inclined in the same direction as the first inclined main grooves;
Wherein the second longitudinal grooves of the plurality of the inclined second land portions each which are divided in the same direction as the dividing and the second inclined main grooves provided we are between the second inclined main grooves,
The first inclined main groove has a first inner end that terminates in communication with the second inclined main groove;
The second inclined main groove has a second inner end that terminates in communication with the first inclined main groove;
The winter tire, wherein the first inclined main groove and the second inclined main groove are provided alternately in a tire circumferential direction . 2. The winter tire according to claim 1, wherein each of the first inclined main groove and the second inclined main groove has an arc shape in which an inclination angle with respect to a tire axial direction gradually decreases toward a tread end side. The winter tire according to claim 1 or 2, wherein the first vertical grooves adjacent to each other through the first inclined main grooves communicate with the first inclined main grooves at different positions in the tire axial direction. The first vertical groove includes an inner first vertical groove and an outer first vertical groove disposed on the outer side in the tire axial direction of the inner first vertical groove. Winter tire. The winter tire according to claim 4, wherein the first inclined sub-groove terminates beyond the inner first longitudinal groove toward the tire equator side. The winter tire according to any one of claims 1 to 5, wherein the second vertical grooves adjacent to each other through the second inclined main groove communicate with the second inclined main groove at different positions in the tire axial direction. . The said 2nd vertical groove contains the inner side 2nd vertical groove and the outer side 2nd vertical groove distribute | arranged to the tire axial direction outer side of the said inside 2nd vertical groove. Winter tire. The winter tire according to claim 7, wherein the second inclined sub-groove terminates beyond the inner second longitudinal groove toward the tire equator side.

Images