JP2010006107A - Pneumatic tire - Google Patents

Pneumatic tire Download PDF

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Publication number
JP2010006107A
JP2010006107A JP2008164261A JP2008164261A JP2010006107A JP 2010006107 A JP2010006107 A JP 2010006107A JP 2008164261 A JP2008164261 A JP 2008164261A JP 2008164261 A JP2008164261 A JP 2008164261A JP 2010006107 A JP2010006107 A JP 2010006107A
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Prior art keywords
tread
block
tire
sipe
rubber
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JP2008164261A
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Japanese (ja)
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JP5291398B2 (en
Inventor
Eisuke Seta
英介 瀬田
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Bridgestone Corp
株式会社ブリヂストン
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Priority to JP2008164261A priority Critical patent/JP5291398B2/en
Publication of JP2010006107A publication Critical patent/JP2010006107A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60CVEHICLE TYRES; TYRE INFLATION; TYRE CHANGING OR REPAIRING; REPAIRING, OR CONNECTING VALVES TO, INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/0041Tyre tread bands; Tread patterns; Anti-skid inserts comprising different tread rubber layers
    • B60C11/005Tyre tread bands; Tread patterns; Anti-skid inserts comprising different tread rubber layers with cap and base layers
    • B60C11/0058Tyre tread bands; Tread patterns; Anti-skid inserts comprising different tread rubber layers with cap and base layers with different cap rubber layers in the axial direction
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B60VEHICLES IN GENERAL
    • B60CVEHICLE TYRES; TYRE INFLATION; TYRE CHANGING OR REPAIRING; REPAIRING, OR CONNECTING VALVES TO, INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES
    • B60C11/00Tyre tread bands; Tread patterns; Anti-skid inserts
    • B60C11/03Tread patterns
    • B60C11/12Tread patterns characterised by the use of narrow slits or incisions, e.g. sipes
    • B60C2011/129Sipe density, i.e. the distance between the sipes within the pattern
    • B60C2011/1295Sipe density, i.e. the distance between the sipes within the pattern variable

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pneumatic tire further improved in on-snow performance. <P>SOLUTION: Each of blocks 40 constituting inside block lines 26, 28 arranged on the tire center side of a tread 16 has harder rubber and higher sipe density than that of each of blocks 44 constituting outside block lines 30, 32 arranged on the shoulder side of the tread 16. The hard rubber is arranged on each of the inside block lines 26, 28 to suppress the fall-down of the blocks 40 due to insufficient block rigidity. This improves edge effects of sipes 46 while suppressing the degradation of the block rigidity. The soft rubber is arranged on each of the outside block lines 30, 32 and the sipe density of each of the blocks 44 is reduced to suppress the lowering of the block rigidity. This increases a surface friction force while suppressing block deformation near contact areas, thus improving a gripping force. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a pneumatic tire that is particularly suitable for use in an automobile traveling on a snowy road.

  Conventionally, in winter pneumatic tires (studless tires), when running on a snowy road, there is a difficulty in that the tire cannot easily grip the snowy road and the tire easily slips on the snow surface. For this reason, as a measure for improving acceleration / braking performance at the start on a snowy road, a design in which a sipe is provided in a tread pattern has been made.

  However, if the number of sipes is increased in order to ensure on-snow acceleration performance, there is a drawback that the on-snow braking performance is likely to deteriorate due to a decrease in block rigidity. Even if measures are taken to set the density of sipes, the rigidity of the block with the increased number of sipes is also lowered and the performance on snow is likely to deteriorate.

Further, for example, Patent Documents 1 and 2 disclose that the tread portion rubber is divided into a plurality of pieces and the tread portion is made of two or more types of rubber, thereby improving the running performance on snowy and ice roads. ing. However, in recent years, higher acceleration / braking performance at the time of start on a snowy road has been demanded.
JP 2001-47815 A Japanese Patent Laid-Open No. 6-1111

  In view of the above fact, an object of the present invention is to provide a pneumatic tire with further improved performance on snow.

  The present inventor conducted the following examination on the mechanism of the expression of the friction coefficient μ on the snow of the tire.

  As shown in FIG. 13, from the snow road surface, compression resistance FA, driving force or braking force due to edge effect (hereinafter referred to as edge effect FD), surface friction force FC, and snow column shear force FB (snow column S). Is acting on the tire TA. Here, the compression resistance FA is the force that the front of the tire presses against the snow surface and becomes running resistance, the edge effect FD is the force generated by the block edge or sipe edge scratching the snow road surface, the surface friction force FC is the rubber surface and the snow road surface The frictional force between them and the snow column shearing force FB indicate the force generated in the tire by shearing the snow in the lug groove. Note that the snow column shear force FB is generated by a mechanism that rotates the gears of the block land portion and the lug groove portion.

  Further, the inventor of the present invention paid attention to the fact that the sipe distribution in the center portion and the shoulder portion is substantially uniform in the conventional winter tire, and the blades forming the sipe are designed as flat plates. And in the conventional winter tire, the rubber | gum kind in a tread rubber layer was generally one kind, and it also paid attention that there was little freedom degree which designs the dynamic elastic modulus in -20 degreeC which contributes to on-snow performance.

  And, as a result of diligent study, the present inventor has determined that the tread rubber on the contact surface side is divided and configured with a plurality of rubber types to have a distribution in the block rigidity and also set the distribution of the number of sipes. I thought. And this inventor conducted experiment and repeated examination, and came to complete this invention.

  According to the first aspect of the present invention, the hardness of the rubber constituting at least the ground contact surface side of the tread portion is different in the tread width direction position, and the sipe density is higher in the tread portion where the rubber is harder than in the tread portion where the rubber is soft. Has been.

  The sipe density is the sipe length per unit area on the tread surface (contact surface).

  In the first aspect of the present invention, the hard rubber is disposed in the tread portion where the sipe density is high, so that the block collapse due to insufficient block rigidity is suppressed. That is, by arranging hard rubber, it is possible to improve the edge effect by sipe while suppressing a decrease in block rigidity.

  In addition, since the soft rubber is arranged in the tread portion where the sipe density is low, the surface friction force with the snow can be effectively increased. In other words, by reducing the sipe density, it is possible to increase the surface friction force while suppressing the deformation of the block in the vicinity of the ground contact surface by suppressing the decrease in the block rigidity, and to improve the grip force.

  In addition, the present inventor conducted the following investigation on the tire center portion and the shoulder portion.

  Since the tire ground contact surface generally has a larger contact length on the tire center side than on the shoulder side, the contribution of the tire center portion is high when starting. In order to improve the acceleration performance on snow, it is desirable to increase the edge effect by increasing the edge component of the center part, but if the edge component is increased too much, the block rigidity will decrease, so the edge tip will be easily deformed, The edge effect generated by penetrating into the snow and scratching it is reduced, and the acceleration performance on snow is deteriorated. In addition, since the center of gravity of the vehicle moves during braking and the load on the front wheel increases, the contact length on the shoulder side on the tire contact surface increases, so the shoulder side contribution is high during braking on snow. In order to improve braking performance on snow, it is desirable to increase the surface friction force by reducing the dynamic elastic modulus at −20 ° C. of the tread rubber constituting the shoulder side (tread shoulder portion). Then, since the block rigidity is lowered, the block in the vicinity of the ground contact surface is easily deformed, the contact area between the rubber and snow is reduced, and the braking performance on snow is deteriorated.

  Therefore, the present inventor has devised a suitable configuration for the hardness and sipe density of the rubber on the tire center side and the shoulder side of the tread portion.

  In the invention according to claim 2, rubber is harder in the tread portion on the tire center side than in the tread portion on the shoulder side.

  In snow acceleration performance, the contribution of the center portion having a large contact length is high, and in snow braking performance, the shoulder portion, which has a great influence during braking, has a high contribution. Therefore, as in the invention according to claim 2, the sipe density of the tread portion on the tire center side is higher than that of the tread portion on the shoulder side, so that the acceleration performance on snow can be improved more effectively. Since the rubber in the tread portion on the side is softer than the tire center side, the braking performance on snow can be improved more effectively.

  In the invention according to claim 3, in the tread portion where the rubber is hard, the sipe density is higher in a range of 1.1 to 3.0 times than in the tread portion where the rubber is soft.

  If the above value (sipe density ratio) is less than 1.1 times, it will be difficult to find a difference in block rigidity. Moreover, when it exceeds 3.0 times, a sipe density will become high too much, the contact area of rubber | gum and snow will fall, and the braking performance on snow will deteriorate easily.

  In the invention according to claim 4, in the tread portion where the rubber is hard, the dynamic elastic modulus of the rubber at −20 ° C. is higher in the range of 1.1 to 20.0 times than in the tread portion where the rubber is soft.

  If the above value (dynamic elastic modulus ratio) is less than 1.1 times, it will be difficult to find a difference in block rigidity. On the other hand, if it exceeds 20.0 times, the dynamic elastic modulus is too low, the deformation of the edge tip increases, the edge effect decreases, and the on-snow acceleration performance tends to deteriorate.

  In a fifth aspect of the present invention, the sipe formed in the tread portion is constituted by a three-dimensional sipe (3D sipe).

  The 3D sipe refers to a sipe that extends while deforming in two directions (a sipe extending in a block tread surface and a sipe depth direction in many cases).

  As a blade for forming a 3D sipe, a blade having an arbitrary shape can be used.

  According to the fifth aspect of the present invention, the block collapse can be suppressed by increasing the contact force between the sipe wall surfaces, and the block rigidity is further increased. Therefore, the snow acceleration performance and snow braking performance can be improved more effectively. The amount of increase in block rigidity due to 3D sipe may be allocated to further increase in sipe density or decrease in dynamic elastic modulus at −20 ° C. of tread rubber.

  Further, in order to effectively bring the sipe wall surfaces into contact with each other in the longitudinal direction, the blade forming the 3D sipe has a shape that is arbitrarily bent with respect to the tire radial direction (sipe depth direction). It is desirable. As a result, the block rigidity in the front-rear direction is increased, the contact area can be increased, and the acceleration / braking performance on snow can be improved.

  Further, in order to effectively bring the sipe wall surfaces into contact with each other in the lateral direction, it is desirable that the blade forming the 3D sipe has a shape that is arbitrarily bent with respect to the block width direction. As a result, the lateral block rigidity is increased, and the contact area can be increased to improve the steering stability performance on snow.

  According to this invention, it can be set as the pneumatic tire which further improved the performance on snow.

  Hereinafter, embodiments will be described and embodiments of the present invention will be described. In the second and subsequent embodiments, the same components as those already described are denoted by the same reference numerals, and description thereof is omitted.

[First Embodiment]
First, the first embodiment will be described. As shown in FIG. 1, a pneumatic tire 10 according to the present embodiment is a studless tire (winter tire) for a passenger car, and a carcass composed of one or a plurality of layers, each end of which is folded by a bead core 11. (For example, radial carcass) 12 is provided.

  On the outer side in the tire radial direction of the crown portion 12C of the carcass 12, a belt layer 14 in which a plurality of (for example, two) belt plies are stacked is embedded.

  A tread portion 16 provided with a groove is formed on the outer side of the belt layer 14 in the tire radial direction. As shown in FIG. 2, the tread portion 16 is formed with a plurality of circumferential grooves (main grooves) 22 along the tire circumferential direction U on the tire equatorial plane (tire center) CL and on both sides thereof. Yes. The tread portion 16 is formed with a plurality of lateral grooves 24 that intersect the tire circumferential direction U. In the present embodiment, the lateral groove 24 is formed along the tire width direction V. Both end portions of each lateral groove 24 communicate with the circumferential groove 22 or extend beyond the tread end T so as to be drained outward in the tire width direction.

  Here, the tread end means that a pneumatic tire is mounted on a standard rim specified in JATMA YEAR BOOK (2006 edition, Japan Automobile Tire Association Standard), and the maximum load in the applicable size and ply rating in JATMA YEAR BOOK. Fills 100% of the air pressure (maximum air pressure) corresponding to the capacity (internal pressure-load capacity correspondence table) as the internal pressure, and indicates the outermost contact portion in the tire width direction when the maximum load capacity is applied. In addition, when TRA standard and ETRTO standard are applied in a use place or a manufacturing place, it follows each standard.

  As shown in FIG. 2, the tread portion 16 includes inner block rows 26 and 28 formed on the tire equatorial plane CL side (tire center side) by a circumferential groove 22 and a lateral groove 24, and a shoulder side (tread end T). The outer block rows 30 and 32 formed on the side) are arranged.

  In the present embodiment, as shown in FIGS. 1 and 2, the tread portion 16 is composed of two types of rubber. The tread portion 16A on the tire center side forming the inner block rows 26, 28 is composed of a hard tread rubber (so-called hard rubber) 34, and the tread portion 16B on the shoulder side forming the outer block rows 30, 32 is A soft tread rubber (so-called soft rubber) 36 is used. More specifically, the dynamic elastic modulus of the tread rubber 34 at −20 ° C. is higher than that of the tread rubber 36.

  Here, the inner block rows 26 and 28 are made of the same kind of rubber and have the same shape. The outer block rows 30 and 32 are made of the same kind of rubber and have the same shape. Therefore, in the following description, the inner block row 26 and the outer block row 30 will be described, and description of the inner block row 28 and the outer block row 32 will be omitted.

  As shown in FIGS. 2 to 4, sipes 46 are formed in each block 40 constituting the inner block row 26 and each block 44 constituting the outer block row 30. In the present embodiment, each sipe 46 is formed along the lateral groove 24 and is substantially parallel to the lateral groove 24. The dimensions of the sipes 46 formed in the blocks 40 and 44 are all the same.

  In the present embodiment, the number of sipes in the block 40 is larger than the number of sipes in the block 44. That is, the sipe density of each block of the inner block row 26 is high, and the sipe density of each block of the outer block row 30 is low.

  As shown in FIG. 3, in this embodiment, five sipes 46A to E are formed in each block 40 constituting the inner block row 26, and six small blocks 42A to F are formed by the five sipes 46. Is formed.

(Function, effect)
Hereinafter, the operation and effect of the present embodiment will be described.

  In this embodiment, in each block 40 of the inner block row 26, the rubber is hard and the sipe density is high. That is, the block rigidity can be maintained or increased even if the number of sipes is dense. Therefore, by arranging hard rubber, the deterioration of the block rigidity is suppressed, the deformation of the tip of the sipe edge is suppressed, the edge effect is effectively generated, and the edge effect by the sipe 46 is improved by increasing the number of sipes. Thus, acceleration performance on snow can be improved efficiently.

  In each block 44 of the outer block row 30, the rubber is soft and the sipe density is low. That is, even if the rubber is soft, the block rigidity can be maintained or increased. Therefore, by reducing the sipe density, it is possible to effectively generate a surface friction force by arranging soft rubber while suppressing the block deformation near the ground contact surface by suppressing the decrease in block rigidity. (Grip force) can be improved efficiently.

  Further, in the acceleration performance on snow, the contribution of the tire center portion having a large contact length is high. Therefore, in this embodiment, the acceleration performance on snow can be improved more effectively because the sipe density on the tire center side is higher than that on the shoulder side. In addition, in the braking performance on snow (braking performance on snow), the contribution of the tread shoulder portion having a large influence during braking is high. Therefore, in the present embodiment, the braking performance on snow can be more effectively improved because the rubber on the shoulder side is softer than the tire center side.

  In the present embodiment, the sipe density in each block 40 in the inner block row 26 is higher than the blocks 44 in the outer block row 30 within a range of 1.1 to 3.0 times. And in each block 40 of the inner side block row | line | column 26, compared with each block 44 of the outer side block row | line | column 30, the dynamic elastic modulus of rubber | gum in -20 degreeC is high in the range of 1.1-20.0 times.

  Thereby, the acceleration performance on the snow on the tire center side and the braking performance on the snow on the shoulder side can be improved more efficiently.

  In addition, in FIG. 2, although the land part of the tread part 16 was shown with the tread pattern which comprised all the blocks, you may comprise with a rib except for some lug grooves.

  Furthermore, a tire in which no circumferential groove is formed is also possible.

  In FIG. 2, the tread pattern is shown as a pattern that is symmetric with respect to the tire equator plane CL, but may be an asymmetric pattern with respect to the tire equator plane CL.

  Furthermore, in the present embodiment, the level of the sipe density is described based on the number of sipe. However, when the sipe is divided and it is difficult to evaluate the substantial number of sipe, the sipe density may be evaluated using edge components in the front-rear direction.

[Second Embodiment]
Next, a second embodiment will be described. In this embodiment, the arrangement positions of the inner block row and the outer block row described in the first embodiment are reversed. That is, as shown in FIG. 5, in the four block rows formed in the tread portion 54, the sipe density is low in the inner block rows 56 and 58 constituting the tire center side, and the outer block rows 60 and 62 on the shoulder side. Then the sipe density is high. The tread rubber 64 constituting the inner block rows 56 and 58 is softer than the tread rubber 66 constituting the outer block rows 60 and 62.

  Also according to the present embodiment, the acceleration performance on snow and the braking performance on snow are improved as compared with the prior art.

[Third Embodiment]
Next, a third embodiment will be described. In the present embodiment, the sipes are all three-dimensional sipes 70 as shown in FIG. 6 as compared to the first embodiment.

  According to this embodiment, the contact force between the sipe wall surfaces is increased, and the block rigidity is further improved.

  The shape of the three-dimensional sipe may be other shapes, for example, a three-dimensional sipe 72 extending in a crank shape in the tire radial direction (block height direction) as shown in FIG. As shown in FIG. 8, it may be a three-dimensional sipe 74 extending in a zigzag shape in the tire radial direction. Further, as shown in FIG. 9, a three-dimensional sipe 76 in which square top portions 75 are arranged according to a certain rule may be used. In addition, as shown in FIG. 10, many types of three-dimensional sipes 79 to 84 may be formed in one block 78. Further, as shown in FIG. 11, a three-dimensional sipe 86 having a shape in which polyhedrons are arranged may be used.

<Test example>
In order to confirm the effect of the present invention, the inventor made two examples of the pneumatic tire according to the first embodiment (hereinafter referred to as the tire of Example 1 and the tire of Example 2), and the air according to the second embodiment. An example of an entered tire (hereinafter referred to as a tire of Example 3), an example of a pneumatic tire according to the third embodiment (hereinafter referred to as a tire of Example 4), and an example of a conventional pneumatic tire (hereinafter referred to as a conventional tire) Example tires) were prepared and performance tests were performed on snow to evaluate acceleration performance and braking performance (braking performance).

In the conventional tire, as shown in FIG. 12, blocks 90 having the same number of sipes are disposed on the tire center side and the shoulder side. The sipe 96 formed in each block 90 has the same shape and does not form a 3D sipe. And, for the tread rubber 94, only one kind of rubber is used without being divided,
As for the block dimensions, in the tire of Example 1, as shown in FIG. 3, in each of the blocks 40 and 44, the tire circumferential direction length L is 27 mm, the tire width direction length M is 22 mm, and the block height (block The depth (H) of the groove for forming the film was 10 mm. The block dimensions (L, M, and H values) of the tires of Examples 2 to 4 and the conventional tire were the same as those of the tire of Example 1.

  The sipe depth h was set to 6.6 mm for both the tires of Examples 1 to 4 and the conventional tire.

  For each tire, the dynamic modulus of elasticity of the tread rubber at −20 ° C. was measured using a spectrometer manufactured by Toyo Seiki Seisakusho, with a test piece having a width of 5 mm, a thickness of 2 mm, and a length of 20 mm and an initial load of 150 gf (1.47 N). It was determined by measuring in an environment of -20 ° C. at a frequency of 50 Hz and a dynamic strain of 1%.

  Table 1 shows the tire conditions for each tire.

  In this test example, for all tires, the tire size was set to 195 / 65R15, the tire was mounted on a 6J-15 rim and the internal pressure was set to 200 kPa. . Here, the “regular load” refers to the maximum load in the applicable size / ply rating defined in the 2007 YEAR BOOK issued by JATMA. The rim size and the internal pressure are based on the applicable rim and air pressure-load capacity correspondence table corresponding to the radial ply tire size defined in the 2007 YEAR BOOK issued by JATMA.

  In this test example, the acceleration performance was measured by measuring the time (acceleration time) required to travel 50 m with the accelerator fully open from a stationary state.

  As for the braking performance, the braking distance from the speed of 40 km / h until full braking was applied was measured, and the average deceleration was calculated from the speed (40 km / h) and the braking distance.

  Then, for both the acceleration performance and the braking performance, an evaluation index 100 based on the average deceleration of the tire of the conventional example was used, and an evaluation index serving as a relative evaluation was calculated for the tires of Examples 1 to 4. The evaluation results are also shown in Table 1.

  The evaluation results in Table 1 indicate that the larger the evaluation index, the higher the performance on snow, that is, the better the acceleration performance on snow and the braking performance on snow. As can be seen from Table 1, the evaluation indices of the tires of Examples 1 to 4 were higher than those of the conventional tires.

  The embodiments of the present invention have been described above with reference to the embodiments. However, these embodiments are merely examples, and various modifications can be made without departing from the scope of the invention. It goes without saying that the scope of rights of the present invention is not limited to these embodiments.

It is tire radial direction sectional drawing of the pneumatic tire which concerns on 1st Embodiment. It is a top view which shows the tread part of the pneumatic tire which concerns on 1st Embodiment. FIGS. 3A to 3C are a plan view, a side view, and a front view seen from the tire circumferential direction, respectively, of blocks formed in the tread portion of the pneumatic tire according to the first embodiment. It is a perspective sectional view of the block formed in the tread part of the pneumatic tire concerning a 1st embodiment. It is a top view which shows the tread part of the pneumatic tire which concerns on 2nd Embodiment. It is a perspective sectional view of the block formed in the tread part of the pneumatic tire concerning a 3rd embodiment. It is a perspective sectional view showing the modification of the block formed in the tread part of the pneumatic tire concerning a 3rd embodiment. It is a perspective sectional view showing the modification of the block formed in the tread part of the pneumatic tire concerning a 3rd embodiment. It is explanatory drawing which shows the modification of the block formed in the tread part of the pneumatic tire which concerns on 3rd Embodiment. It is a perspective sectional view showing the modification of the block formed in the tread part of the pneumatic tire concerning a 3rd embodiment. FIGS. 11A and 11B are explanatory views showing modifications of the blocks formed in the tread portion of the pneumatic tire according to the third embodiment. It is a top view which shows the tread part of the conventional example tire used by the test example. FIGS. 13A and 13B are a schematic partial side sectional view showing that a conventional pneumatic tire rolls on a snow road surface, and a side sectional view of a block in contact with the snow road surface, respectively. (The number of sipes is omitted in FIG. 13 (A). In addition, the region marked with dots in FIG. 13 (B) indicates the part scratching the snow road surface).

Explanation of symbols

10 Pneumatic tire 16 Tread portion 16A Tread portion 16B Tread portion 46 Sipe 54 Tread portion 70 3D sipe 72 3D sipe 74 3D sipe 76 3D sipe 79 3D sipe 80 3D sipe 81 3D sipe 82 3D sipe 83 3D Sipe 84 3D Sipe 86 3D Sipe S
94 Tread rubber 96 Sipe V Tire width direction

Claims (5)

  1. The hardness of the rubber that constitutes at least the ground contact surface side of the tread part differs in the tread width direction position
    A pneumatic tire in which the tread part with hard rubber has a higher sipe density than the tread part with soft rubber.
  2.   The pneumatic tire according to claim 1, wherein the tread portion on the tire center side is harder than the tread portion on the shoulder side.
  3.   The pneumatic tire according to claim 1 or 2, wherein a sipe density is higher in a range of 1.1 to 3.0 times in a tread portion where rubber is harder than in a tread portion where rubber is soft.
  4.   4. The dynamic elastic modulus of the rubber at −20 ° C. is higher in the range of 1.1 to 20.0 times in the tread portion where the rubber is hard than in the tread portion where the rubber is soft. The pneumatic tire according to item.
  5.   The pneumatic tire according to any one of claims 1 to 4, wherein a sipe formed in the tread portion is a three-dimensional sipe.
JP2008164261A 2008-06-24 2008-06-24 Pneumatic tire Active JP5291398B2 (en)

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103101404A (en) * 2011-11-14 2013-05-15 横滨橡胶株式会社 Pneumatic tire
JP2013244812A (en) * 2012-05-24 2013-12-09 Bridgestone Corp Pneumatic tire
JP2013244811A (en) * 2012-05-24 2013-12-09 Bridgestone Corp Pneumatic tire
JP2014046743A (en) * 2012-08-30 2014-03-17 Yokohama Rubber Co Ltd:The Pneumatic tire
EP2750904A2 (en) * 2011-08-31 2014-07-09 MICHELIN Recherche et Technique S.A. Tire tread with improved snow/dry traction
EP3006233A4 (en) * 2013-06-05 2016-06-29 Bridgestone Corp Tire
EP3040215A4 (en) * 2013-08-28 2016-08-31 Bridgestone Corp Heavy duty pneumatic tire
US9566829B2 (en) 2012-02-01 2017-02-14 Bridgestone Corporation Pneumatic tire

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Publication number Priority date Publication date Assignee Title
JPH09136509A (en) * 1995-11-15 1997-05-27 Bridgestone Corp Studless pneumatic tire
JP2000142035A (en) * 1998-11-18 2000-05-23 Toyo Tire & Rubber Co Ltd Pneumatic tire
JP2001047815A (en) * 1999-05-31 2001-02-20 Bridgestone Corp Pneumatic tire
WO2005097523A1 (en) * 2004-04-09 2005-10-20 Bridgestone Corporation Pneumatic tire

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH09136509A (en) * 1995-11-15 1997-05-27 Bridgestone Corp Studless pneumatic tire
JP2000142035A (en) * 1998-11-18 2000-05-23 Toyo Tire & Rubber Co Ltd Pneumatic tire
JP2001047815A (en) * 1999-05-31 2001-02-20 Bridgestone Corp Pneumatic tire
WO2005097523A1 (en) * 2004-04-09 2005-10-20 Bridgestone Corporation Pneumatic tire

Cited By (15)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2750904A2 (en) * 2011-08-31 2014-07-09 MICHELIN Recherche et Technique S.A. Tire tread with improved snow/dry traction
EP2750904A4 (en) * 2011-08-31 2015-04-15 Michelin Rech Tech Tire tread with improved snow/dry traction
DE102012220564A1 (en) 2011-11-14 2013-05-16 The Yokohama Rubber Co., Ltd tire
JP2013103621A (en) * 2011-11-14 2013-05-30 Yokohama Rubber Co Ltd:The Pneumatic tire
DE102012220564B4 (en) * 2011-11-14 2019-06-27 The Yokohama Rubber Co., Ltd tire
US9855801B2 (en) 2011-11-14 2018-01-02 The Yokohama Rubber Co., Ltd. Pneumatic tire
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JP2013244811A (en) * 2012-05-24 2013-12-09 Bridgestone Corp Pneumatic tire
JP2014046743A (en) * 2012-08-30 2014-03-17 Yokohama Rubber Co Ltd:The Pneumatic tire
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