JP5315654B2 - Pneumatic tire - Google Patents

Description

  The present invention relates to a pneumatic tire for an automobile in consideration of, for example, the behavioral stability of a vehicle at the time of limit running.

  In general, this type of pneumatic tire has a plurality of blocks constituting a tread pattern on the tread surface, and is disposed just outside the tread surface in the tire width direction with respect to the grounding end of the tread surface. It is known that a plurality of outer blocks are formed, each outer block is formed of a rubber material that is softer than the other blocks, and the rigidity of the outer block is lowered by the amount of the soft rubber material. (For example, refer to Patent Document 1).

As another pneumatic tire, the tread surface has a plurality of blocks that form a tread pattern, and a plurality of outer blocks that are arranged so as to straddle the grounded end of the tread surface and constitute a part of each block. It is known that a groove called a sipe is provided in each outer block so that the rigidity of the outer block is lowered by the amount of the groove (see, for example, Patent Document 2).
JP 2006-297980 A JP 2006-175959 A

  By the way, in each of the pneumatic tires, the rigidity of the outer block is set to be low by a rubber material or a groove. Therefore, when each outer block comes into contact with the road surface due to a limit running that causes a large lateral G in the vehicle, The grip force is reduced by the amount that the rigidity is reduced, and the cornering force at the time of limit driving can be reduced.

  On the other hand, in each of the pneumatic tires, the pitch in the tire circumferential direction of each block and each outer block is changed in order to reduce noise caused by the tread pattern. For example, the pneumatic tires are arranged in the tire circumferential direction. Each outer block is constituted by outer blocks of large pitch, medium pitch and small pitch. For this reason, the outer block of the large pitch is more rigid than the outer block of the small pitch, and when each outer block comes into contact with the road surface due to marginal driving, the grip force of the outer block of the large pitch becomes smaller than that of the outer block of the small pitch. There is a problem that the grip force becomes larger and the large pitch outer block wears faster than the small pitch outer block, resulting in uneven wear.

  The present invention has been made in view of the above problems, and its object is to reduce the cornering force at the time of limit running, and to reduce noise caused by the tread pattern, An object of the present invention is to provide a pneumatic tire capable of preventing uneven wear.

In order to achieve the above object, the present invention provides a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface, wherein the tread surface has a grounding end on the outer side in the vehicle width direction among grounding ends on both sides in the tire width direction. A plurality of outer blocks that are provided so as to straddle and are arranged so as to be aligned in the tire circumferential direction, and are provided in each outer block in order to reduce the rigidity of each outer block. , and a groove or Ranaru recess extending in the tire width direction, wherein configured to the tire circumferential direction of the pitch of the outer block is two or more, the concave portion of the length of the tire width direction outer side from each other in the outer block And the volume outside the grounded end of the recess of each outer block is set according to the tire circumferential pitch of each outer block. By, formed as a reduction in stiffness as the tire circumferential direction of the pitch of the outer block is large outer block increases, any relative outer block, other high outside pitch than among the outer block The ratio of the pitch of the block is R1, and the ratio of the volume outside the grounded end of the recess provided in the other outer block is R2 with respect to the volume outside the grounded end of the recessed part provided in the arbitrary outer block. In this case, the value of R2 is configured to be 1.1 or more and 2 × R1 or less .

In order to achieve the above object , the present invention provides a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface, and a ground contact on a vehicle width direction outer side of ground contact ends on both sides of the tread surface in the tire width direction. In order to reduce the rigidity of the plurality of outer blocks provided on the outer sides in the tire width direction with respect to the ends and arranged in a row in the tire circumferential direction and constituting a part of each of the blocks, and the outer blocks the respectively provided on each outer block, and a groove or Ranaru recess extending in the tire width direction, constitutes the so tire circumferential direction of the pitch of the outer block is two or more, the concave portion of each outer block They are formed so that the lengths on the outer sides in the tire width direction are different from each other, and the volume outside the ground contact end of the concave portion of each outer block is set to the tie of each outer block. By setting in accordance with the circumferential direction of the pitch, formed as a reduction in the rigidity of the more outer block the tire circumferential direction of the pitch of the outer block is large increases, for any outer block of each outer block, it R1 is a pitch magnification of the other outer block having a larger pitch than that of the concave portion provided in the arbitrary outer block and the volume outside the ground end of the concave portion provided in the arbitrary outer block is outside the ground end of the concave portion provided in the other outer block. When the volume ratio of R2 is R2, the value of R2 is configured to be not less than R1 and not more than 2 × R1 .

  As a result, each outer block is provided with a recess such as a groove or a hole in order to reduce rigidity, so that when each outer block comes into contact with the road surface due to, for example, marginal driving, the grip force of each outer block is increased. It becomes smaller by the amount provided with the recess. In addition, since the outer blocks are configured to have unequal pitches in the tire circumferential direction, noise caused by the tread pattern can be reduced. Furthermore, since each outer block is provided with a recess so that the rigidity of the outer block increases as the pitch in the tire circumferential direction of the outer block increases, for example, when each outer block comes into contact with the road surface due to limit travel, for example. In addition, the difference between the grip force of the outer block having a large pitch and the grip force of the outer block having a small pitch can be reduced.

  According to the present invention, for example, when each outer block comes into contact with the road surface due to limit driving, the grip force of the outer block is reduced by the amount of the recessed portion, so that the cornering force at the time of limiting driving is reduced and the vehicle behavior is reduced. Stability can be improved and noise caused by the tread pattern can also be reduced. Furthermore, when each outer block comes into contact with the road surface due to marginal driving, the difference between the grip force of the outer block with a larger pitch and the grip force of the outer block with a smaller pitch can be reduced. It is possible to prevent uneven wear in which a difference occurs in the wear amount of each outer block.

  1 to 5 show an embodiment of the present invention. FIG. 1 is a sectional view of a tire, FIG. 2 is a development of a main part of a tread surface, and FIGS. 3 and 4 are sectional views taken along line AA in FIG. FIG. 5 and FIG. 5 are tables showing the evaluation results.

  This pneumatic tire 1 is a well-known automobile pneumatic tire having a carcass, a belt, a bead and the like. As shown in FIGS. 1 and 2, the tread surface 2 of the pneumatic tire 1 has a plurality of longitudinal grooves 10 formed to extend in the tire circumferential direction and a plurality of grooves formed to extend in the tire width direction. A horizontal groove 11 is provided, and a plurality of blocks 20 constituting a tread pattern by each vertical groove 10 and each horizontal groove 11 are provided on the tread surface 2. A part of each block 20 is constituted by a plurality of outer blocks 30.

  Each of the outer blocks 30 is provided so as to straddle the grounding end 3 on the outer side in the vehicle width direction which is outside when the grounding end 3 on both sides of the tread surface 2 in the tire width direction is attached to the vehicle, and is arranged in the tire circumferential direction. Are arranged as follows. Here, the ground contact ends 3 on both sides in the tire width direction are both ends of the ground contact width defined by JATMA. That is, the pneumatic tire 1 is assembled to a specified rim and filled with air up to a specified internal pressure, and is brought into contact with the plane portion in a stationary state and is subjected to a specified load. It is the outermost both ends of the tread portion 2 in contact in the tire width direction.

  Each outer block 30 includes a first outer block 31, a second outer block 32, and a third outer block 33. The pitch P2 in the tire circumferential direction of the second outer block 32 is the tire circumferential direction of the first outer block 31. The pitch P3 in the tire circumferential direction of the third outer block 33 is 1.4 times the pitch P1 in the tire circumferential direction of the first outer block 31. The magnifications of the pitch (1.2 times and 1.4 times) are merely examples, and other magnifications can be set. The pitches P1, P2, and P3 of the outer blocks 31, 32, and 33 are distances in the tire circumferential direction between the lateral grooves 11 that form the outer blocks 31, 32, and 33, respectively. Each of the outer blocks 31, 32, and 33 is connected in series in the tire circumferential direction. Thus, each outer block 30 has three types of unequal pitches in the tire circumferential direction. Each block 20 also has an unequal pitch in the tire circumferential direction.

  The outer blocks 31, 32, 33 are provided with grooves 31a, 32a, 33a, respectively, in order to reduce their rigidity. Each groove 31a, 32a, 33a is formed to extend in the tire width direction, and each groove 31a, 32a, 33a is formed to have a width dimension of 0.5 mm to 2.0 mm. Each of the grooves 31a, 32a, and 33a is generally called a sipe, and corresponds to a recess described in the claims. Each groove 31a, 32a, 33a is formed so as to straddle the grounding end 3. The groove 33a of the third outer block 33 is formed longer in the tire width direction than the groove 32a of the second outer block 32, and the volume outside the ground contact edge 3 in the groove 33a of the third outer block 33 (indicated by hatching in FIG. 4). The volume of the portion) is approximately 1.4 times the volume outside the ground contact 3 in the groove 31a of the first outer block 31. Further, the groove 32a of the second outer block 32 is formed longer in the tire width direction than the groove 31a of the first outer block 31, and the volume outside the ground contact edge 3 in the groove 32a of the second outer block 32 is the first outer block. This is approximately 1.2 times the volume outside the ground contact 3 in the 31 groove 31a. Here, the greater the volume of the grooves 31a, 32a, 33a provided in each outer block 30, the greater the reduction in rigidity of each outer block 30, so that the rigidity reduction by the grooves 33a of the third outer block 33 is the second. The rigidity reduction due to the groove 32a of the second outer block 32 is greater than the rigidity reduction due to the groove 31a of the first outer block 31, which is greater than the rigidity reduction due to the groove 32a of the outer block 32. That is, the grooves 31a, 32a, and 33a are provided in each outer block 30 so that the rigidity of the outer block 30 is reduced as the pitch of the outer blocks 30 in the tire circumferential direction is increased.

  In the pneumatic tire 1 configured as described above, the inside of each ground contact 3 is mainly in contact with the road surface in the tread portion 2 when the vehicle is traveling normally. Further, at the time of limit traveling in which a large lateral G is generated in the vehicle, the outside of the ground contact end 3 outside the vehicle width direction in the tread portion 2 also contacts the road surface. That is, at the time of the limit running, the portion outside the ground contact 3 in each outer block 30 also contacts the road surface.

  Here, since each outer block 30 is provided with grooves 31a, 32a, 33a in order to reduce the rigidity, when each outer block 30 comes into contact with the road surface by the limit running, the grip of each outer block 30 is gripped. The force is reduced by the amount provided for each groove 31a, 32a, 33a. Moreover, since the pitch in the tire circumferential direction of each block 20 is an unequal pitch and the pitch in the tire circumferential direction of each outer block 30 is also an unequal pitch, noise caused by the tread pattern can be reduced. Can be reduced. Further, since the outer block 30 is provided with grooves 31a, 32a and 33a so that the rigidity of the outer block 30 is increased as the pitch in the tire circumferential direction of the outer block 30 increases, When the block 30 comes into contact with the road surface, for example, the difference between the grip force of the third outer block 33 having a large pitch and the grip force of the first outer block 31 having a small pitch can be reduced.

  Thus, according to the present embodiment, when each outer block 30 comes into contact with the road surface due to limit travel, the grip force of each outer block 30 is reduced by the amount provided for each groove 31a, 32a, 33a. It is possible to improve the behavior stability of the vehicle by reducing the cornering force during the limit running. Moreover, since the pitch in the tire circumferential direction of each outer block 30 is also an unequal pitch, noise caused by the tread pattern can also be reduced. Furthermore, when each outer block 30 comes into contact with the road surface due to limit travel, for example, the difference between the grip force of the third outer block 33 having a large pitch and the grip force of the first outer block 31 having a small pitch can be reduced. Therefore, it is possible to prevent uneven wear in which a difference occurs in the wear amount of each outer block 30 according to the size of the pitch.

  Here, the magnification R1 of the pitch of the second outer block 32 having a larger pitch than that of the first outer block 31 is 1.2 times, and the grounding end 3 of the groove 31a provided in the first outer block 31. The volume magnification R2 on the outer side of the ground contact end 3 of the groove 32a provided in the second outer block 32 is 1.2 times the volume on the outer side. Further, the magnification R1 of the pitch of the third outer block 33 having a pitch larger than that of the first outer block 31 is 1.4, and the ground end 3 of the groove 31a provided in the first outer block 31 The magnification R2 of the volume outside the ground contact 3 of the groove 33a provided in the third outer block 33 is 1.4 times the volume at the outside. That is, the value of the volume magnification R2 is equal to the pitch magnification R1. Here, a plurality of pneumatic tires 1 having different values of α are formed by setting the value of the volume magnification R2 to α × R1, and for each pneumatic tire 1, evaluation of the cornering force at the limit running, feeling at the limit running And uneven wear were evaluated (see Examples 2 to 5 in FIG. 5). In Examples 2 to 5, the volume of each groove 31a, 32a, 33a outside the ground contact 3 is adjusted by the length of each groove 31a, 32a, 33a. Further, the volume ratio R2 of the groove 32a provided on the second outer block 32 outside the ground end 3 to the volume outside the ground end 3 of the groove 31a provided on the first outer block 31 is 1.1. And the magnification R2 of the volume outside the grounding end 3 of the groove 33a provided in the third outer block 33 with respect to the volume outside the grounding end 3 of the groove 32a provided in the second outer block 32. 1.1 times the volume ratio R2 of the volume outside the ground end 3 of the groove 33a provided in the third outer block 33 with respect to the volume outside the ground end 3 of the groove 31a provided in the first outside block 31 A pneumatic tire 1 having a diameter of 1.21 was also molded and evaluated as described above (see Example 1 in FIG. 5).

  For the evaluation, a pneumatic tire for automobile having a size of 235 / 40R18 was used. Further, the evaluation of the cornering force during the limit running was performed by measuring the maximum cornering force (maximum CF) using a flat belt tester. The flat belt testing machine rotates the endless belt so that a part of the circumferential direction is flat, and the pneumatic tire 1 is driven by the flat part, and the pneumatic belt The cornering force of the tire 1 can be measured. In addition, the evaluation of feeling at the time of marginal driving was performed by sensory evaluation of the driver with the pneumatic tire 1 attached to an SUV vehicle (sport multipurpose vehicle). In addition, the evaluation of uneven wear is performed by measuring the difference in the amount of wear corresponding to the pitch of each outer block 30 after the pneumatic tire 1 is mounted on an SUV vehicle and a predetermined running is performed. It was. In addition, the pneumatic tire 1 in which the volume of the groove 32a of the second outer block 32 and the volume of the groove 33a of the third outer block 31 was equal to the volume of the groove 31a of the first outer block 31 was also molded and subjected to comparative evaluation (FIG. See comparative example 5). In FIG. 5, the results of the above evaluations are indexed with the evaluation result of the comparative example as 100. The maximum cornering force is better as the numerical value is smaller, and the feeling during limit running and uneven wear are better as the numerical value is larger. It is.

  From the evaluation results of FIG. 5, even when the volume ratio R2 is 1.1 or more (Example 1), the cornering force is reduced, the feeling at the time of limit running is improved, and the uneven wear property is compared with the comparative example. Improvement is recognized. Moreover, if the value of α is 1.0 or more and 2.0 or less, a reduction in cornering force, an improvement in feeling during limit running, and an improvement in uneven wear are recognized more significantly than in the comparative example. In addition, when the value of α is 2.2, a reduction in cornering force and an improvement in feeling at the time of limit running are remarkably recognized as compared with the comparative example, but the wear amount of the third outer block 33 having the largest pitch. Was larger than the wear amount of the first outer block 31 having the smallest pitch, and no difference from the comparative example was observed in terms of uneven wear. That is, when the volume ratio R2 is 1.1 or more and 2.0 × R1 or less, a reduction in cornering force, an improvement in feeling during limit running, and an improvement in uneven wear are recognized with respect to the comparative example. If the magnification R2 is 1.0 × R1 or more and 2.0 × R1 or less, a reduction in cornering force, an improvement in feeling during limit running, and an improvement in uneven wear are recognized with respect to the comparative example.

  In Examples 2-5, the volume of each groove 31a, 32a, 33a outside the ground contact 3 is adjusted by the length of each groove 31a, 32a, 33a. Even when the volume outside the ground end 3 is adjusted by the depth of each groove 31a, 32a, 33a, the volume outside the ground end 3 of each groove 31a, 32a, 33a is the length of each groove 31a, 32a, 33a. Even when adjusted by the depth, it is possible to achieve the same effect as described above (see Examples 6 and 7 in FIG. 5). Here, the volume magnification R2 of Examples 6 and 7 is 1.0 × R1.

  In the present embodiment, the grooves 31a, 32a, 33a are provided in the outer blocks 31, 32, 33, respectively, and the grooves 31a, 32a, 33a are set to have different lengths. The larger the pitch, the greater the reduction in the rigidity of the outer block 30. On the other hand, as shown in FIG. 7, the first outer block 31 is provided with grooves 31b, the second outer block 32 is provided with two grooves 32b, and the third outer block 33 is provided with three grooves 33b. It is also possible to configure the outer block 30 so that the rigidity of the outer block 30 is reduced as the pitch in the tire circumferential direction of the outer block 30 is increased. In the case of FIG. 7, the volume outside the grounding end 3 of each groove 32 a provided in the second outside block 32 is added to the volume outside the grounding end 3 of the groove 31 a provided in the first outside block 31. The volume magnification R2 is 1.2, and the grounding end 3 of each groove 33a provided in the third outer block 33 with respect to the volume outside the grounding end 3 of the groove 31a provided in the first outer block 31. The volume ratio R2 of the total volume on the outside of the lens is 1.4. That is, the volume ratio R2 is 1.0 × R1, and when such a pneumatic tire 1 is molded and evaluated in the same manner as described above, the cornering force is reduced compared to the comparative example, and the performance during the limit running is reduced. The improvement of the ring and the improvement of uneven wear are remarkably observed (see Example 8 in FIG. 6).

  Further, as shown in FIG. 8, FIG. 9, or FIG. 32a. It is also possible to set 33a to different lengths. In this case, the volume magnification R2 is 1.0 × R1, and when such a pneumatic tire 1 is molded and evaluated in the same manner as described above, the cornering force is reduced with respect to the comparative example, at the time of limit running. The improvement in feeling and the improvement in uneven wear are remarkably observed (see Example 9 in FIG. 6).

In the present embodiment, grooves 31a, 32a, 33a are provided in the outer blocks 31, 32, 33, respectively, and the grooves 31a, 32a, 33a are set to have different volumes from each other. The larger the pitch, the greater the reduction in rigidity of the outer block 30. On the other hand, as shown in FIG. 11, a groove 31c is provided in the first outer block 31, a groove 32c equivalent to the groove 31c is provided in the second outer block 32, and a plurality of holes 32d are provided. By providing the groove 33c equivalent to the groove 31c and a plurality of holes 33d, it is possible to increase the rigidity of the outer block 30 as the pitch of the outer block 30 in the tire circumferential direction increases. is there. In this case, the volume outside the grounding end 3 of the groove 32c provided in the first outer block 31 and the volume outside the grounding end 3 of the groove 32c provided in the second outer block 32 and the hole 32d are totaled. The volume ratio R2 is 1.2, and the grounding of the groove 33c and the hole 33d provided in the third outer block 33 with respect to the volume outside the grounding end 3 of the groove 31c provided in the first outer block 31. The volume ratio R2 of the total volume outside the end 3 is 1.4 times. That is, the volume ratio R2 is 1.0 × R1, and when such a pneumatic tire 1 is molded and evaluated in the same manner as described above, the cornering force is reduced compared to the comparative example, and the performance during the limit running is reduced. The improvement of the ring and the improvement of uneven wear are recognized remarkably (see Example 10 in FIG. 6) .

  In the present embodiment, the grooves 31a, 32a, and 33a are formed so as to straddle the grounding end 3. However, the grooves 31a, 32a, and 33a are provided only outside the grounding end 3. In this case as well, it is possible to achieve the same effect as described above.

  In addition, in this embodiment, what provided each outer side block 30 so that the grounding end 3 of the vehicle width direction outer side among each grounding end 3 of the tread surface 2 was provided was shown. On the other hand, for example, when the ground contact edge 3 on the outer side in the vehicle width direction coincides with the outer edge in the tire width direction on the row of a certain block 20, It is also possible to provide each outer block 40 on the outside (see FIG. 12).

  In this case, each outer block 40 includes a first outer block 41, a second outer block 42, and a third outer block 43, and the ratios P1, P2, P3 in the tire circumferential direction of the respective outer blocks 41, 42, 43. The ratio is the same as in the case of each outer block 30. The first outer block 41 is provided with a groove 41a, the second outer block 42 is provided with two grooves 42a, and the third outer block 43 is provided with three grooves 43a. In the case of FIG. 12, the total volume magnification R2 of each groove 42a provided in the second block 42 is 1.2 times the volume of the groove 41a provided in the first block 41. The total volume magnification R2 of each groove 43a provided in the third block 43 with respect to the volume of the groove 41a provided in is 1.4. That is, the volume ratio R2 is 1.0 × R1, and when such a pneumatic tire 1 is molded and evaluated in the same manner as described above, the cornering force is reduced compared to the comparative example, and the performance during the limit running is reduced. The improvement of the ring and the improvement of uneven wear are recognized remarkably (see Example 11 in FIG. 6). Thus, since it is comprised so that the reduction | decrease of the rigidity of the outer block 40 may become so large that the pitch of the tire circumferential direction of the outer block 40 is large, the effect equivalent to the case where the said outer block 30 is provided is achieved. Is possible. Further, it is possible to adjust the rigidity of each outer block 40 by the same method as shown in FIG. 2, FIG. 8, FIG. 9 or FIG.

  In the present embodiment, the outer circumferential blocks 30 and 40 have three types of pitches in the tire circumferential direction. However, if the outer circumferential blocks 30 and 40 have two or more pitches in the tire circumferential direction, It is possible to achieve the same effect as described above.

  Moreover, in this embodiment, what showed each outer side block 30 and 40 in the grounding end 3 side of the vehicle width direction outer side among each grounding end 3 of the tread surface 2 was shown. On the other hand, when the pneumatic tire 1 has a symmetrical tread pattern and the mounting direction to the vehicle is arbitrary, the outer blocks 30 and 40 are respectively provided on both the grounding ends 3 of the tread surface 2. It is also possible to provide. In this case, the above-described effects can be achieved regardless of the direction in which the pneumatic tire 1 is attached to the vehicle.

Sectional drawing of the tire which shows one Embodiment of this invention Development of the main part of the tread surface AA line sectional view in FIG. AA line sectional view in FIG. Table showing evaluation results Table showing evaluation results The principal part expanded view of the tread surface which shows the 1st modification of this embodiment. The principal part expanded view of the tread surface which shows the 2nd modification of this embodiment. The principal part expanded view of the tread surface which shows the 3rd modification of this embodiment. The principal part expanded view of the tread surface which shows the 4th modification of this embodiment. The principal part expanded view of the tread surface which shows the 5th modification of this embodiment. The principal part expanded view of the tread surface which shows the 6th modification of this embodiment.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Pneumatic tire, 2 ... Tread surface, 3 ... Grounding end, 10 ... Vertical groove, 11 ... Horizontal groove, 20 ... Block, 30 ... Outer block, 31 ... 1st outer block, 31a ... Groove, 31b ... Groove, 31c ... groove, 32 ... second outer block, 32a ... groove, 32b ... groove, 32c ... groove, 32d ... hole, 33 ... third outer block, 33a ... groove, 32b ... groove, 32c ... groove, 32d ... hole.

Claims (6)

In a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface,
The tread surface is provided so as to straddle the ground contact ends on the vehicle width direction outside of the ground contact ends on both sides in the tire width direction, and is arranged so as to be aligned with each other in the tire circumferential direction. An outer block,
Respectively provided on each outer block to reduce the rigidity of the outer blocks, and a groove or Ranaru recess extending in the tire width direction,
The pitch in the tire circumferential direction of each outer block is configured to be two or more types,
By forming the recesses of each outer block so that the lengths on the outer sides in the tire width direction are different from each other, and setting the volume outside the ground contact end of the recesses of each outer block according to the pitch in the tire circumferential direction of each outer block The outer block is formed such that the greater the pitch in the tire circumferential direction, the greater the reduction in rigidity of the outer block .
R1 is the pitch magnification of another outer block having a larger pitch than any outer block of each outer block, and the volume outside the ground contact edge of the recess provided in the outer block is A pneumatic tire characterized by having a value of R2 of 1.1 or more and 2 × R1 or less, where R2 is a volume ratio outside the ground contact edge of the concave portion provided in another outer block. . In a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface,
The tread surface is provided so as to straddle the ground contact ends on the vehicle width direction outside of the ground contact ends on both sides in the tire width direction, and is arranged so as to be aligned with each other in the tire circumferential direction. An outer block,
In order to reduce the rigidity of each outer block, each outer block is provided with a recess made of a groove extending in the tire width direction,
The pitch in the tire circumferential direction of each outer block is configured to be two or more types,
  By forming the recesses of each outer block so that the lengths on the outer sides in the tire width direction are different from each other, and setting the volume outside the ground contact end of the recesses of each outer block according to the pitch in the tire circumferential direction of each outer block The outer block is formed such that the greater the pitch in the tire circumferential direction, the greater the reduction in rigidity of the outer block.
R1 is the pitch magnification of another outer block having a larger pitch than any outer block of each outer block, and the volume outside the ground contact edge of the recess provided in the outer block is When the magnification of the volume outside the ground contact end of the recess provided in the other outer block is R2, the value of R2 is configured to be not less than R1 and not more than 2 × R1.
A pneumatic tire characterized by that. In a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface,
The tread surface is provided immediately outside in the tire width direction with respect to a grounding end on the vehicle width direction outside of the grounding ends on both sides in the tire width direction, and is arranged so as to be aligned with each other in the tire circumferential direction. A plurality of outer blocks constituting the part;
In order to reduce the rigidity of each outer block, each outer block is provided with a recess made of a groove extending in the tire width direction,
The pitch in the tire circumferential direction of each outer block is configured to be two or more types,
By forming the recesses of each outer block so that the lengths on the outer sides in the tire width direction are different from each other, and setting the volume of the recesses of each outer block according to the pitch in the tire circumferential direction of each outer block, The larger the pitch in the tire circumferential direction, the greater the reduction in rigidity of the outer block,
R1 is a pitch magnification of another outer block having a pitch larger than that of an arbitrary outer block among the outer blocks, and the other outer block is defined with respect to the volume of the concave portion provided in the arbitrary outer block. When the magnification of the volume of the recess provided in R2 is R2, the value of R2 is configured to be 1.1 or more and 2 × R1 or less.
A pneumatic tire characterized by that. In a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface,
The tread surface is provided immediately outside in the tire width direction with respect to a grounding end on the vehicle width direction outside of the grounding ends on both sides in the tire width direction, and is arranged so as to be aligned with each other in the tire circumferential direction. A plurality of outer blocks constituting the part;
In order to reduce the rigidity of each outer block, each outer block is provided with a recess made of a groove extending in the tire width direction,
The pitch in the tire circumferential direction of each outer block is configured to be two or more types,
By forming the recesses of each outer block so that the lengths on the outer sides in the tire width direction are different from each other, and setting the volume of the recesses of each outer block according to the pitch in the tire circumferential direction of each outer block, The larger the pitch in the tire circumferential direction, the greater the reduction in rigidity of the outer block,
R1 is a pitch magnification of another outer block having a pitch larger than that of an arbitrary outer block among the outer blocks, and the other outer block is defined with respect to the volume of the concave portion provided in the arbitrary outer block. When the magnification of the volume of the recess provided in R2 is R2, the value of R2 is configured to be R1 or more and 2 × R1 or less.
A pneumatic tire characterized by that. In a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface,
The tread surface is provided so as to straddle the ground contact ends on the vehicle width direction outside of the ground contact ends on both sides in the tire width direction, and is arranged so as to be aligned with each other in the tire circumferential direction. An outer block,
In order to reduce the rigidity of each outer block, each outer block is provided with a groove extending in the tire width direction and a recess made of a hole,
The pitch in the tire circumferential direction of each outer block is configured to be two or more types,
By forming the recesses of each outer block so that the number of holes is different from each other, and setting the volume outside the ground contact end of the recesses of each outer block according to the pitch in the tire circumferential direction of each outer block, The larger the pitch in the tire circumferential direction, the greater the reduction in rigidity of the outer block,
R1 is the pitch magnification of another outer block having a larger pitch than any outer block of each outer block, and the volume outside the ground contact edge of the recess provided in the outer block is When the magnification of the volume outside the ground contact end of the recess provided in the other outer block is R2, the value of R2 is configured to be 1.1 or more and 2 × R1 or less.
A pneumatic tire characterized by that. In a pneumatic tire having a plurality of blocks constituting a tread pattern on a tread surface,
The tread surface is provided so as to straddle the ground contact ends on the vehicle width direction outside of the ground contact ends on both sides in the tire width direction, and is arranged so as to be aligned with each other in the tire circumferential direction. An outer block,
In order to reduce the rigidity of each outer block, each outer block is provided with a groove extending in the tire width direction and a recess made of a hole,
The pitch in the tire circumferential direction of each outer block is configured to be two or more types,
By forming the recesses of each outer block so that the number of holes is different from each other, and setting the volume outside the ground contact end of the recesses of each outer block according to the pitch in the tire circumferential direction of each outer block, The larger the pitch in the tire circumferential direction, the greater the reduction in rigidity of the outer block,
R1 is a pitch magnification of another outer block having a pitch larger than that of an arbitrary outer block among the outer blocks, and the other outer block is defined with respect to the volume of the concave portion provided in the arbitrary outer block. When the magnification of the volume of the recess provided in R2 is R2, the value of R2 is configured to be R1 or more and 2 × R1 or less.
A pneumatic tire characterized by that.

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